interacts_with DB00091?
DB01281 inhibits effector T cells through regulatory T cells and TGF-β . The P10747 costimulatory receptor is a critical regulator of T cell function , making it an attractive therapeutic target for the treatment of immune-mediated diseases . DB01281 , now approved for use in humans , prevents naive T cell activation by binding to P33681 proteins and blocking engagement of P10747 . However , DB01281 suppresses inflammation even if administered when disease is established , suggesting alternative mechanisms . We identified a novel , P10747 -independent mechanism by which DB01281 inhibits activated T cells . We show that in vitro , DB01281 synergizes with NO from bone marrow-derived macrophages to inhibit T cell proliferation . Depletion of regulatory T cells ( Tregs ) or interference with TGF-β signaling abrogated the inhibitory effect of DB01281 . Parallel in vivo experiments using an allergic airway inflammation model demonstrated that this novel mechanism required both macrophages and regulatory T cells . Furthermore , DB01281 was ineffective in P84022 -deficient mice , supporting a requirement for TGF-β signaling . Thus , in addition to preventing naive T cells from being fully activated , DB01281 can turn off already activated effector T cells by an NO/regulatory T cell/TGF-β-dependent pathway . This mechanism is similar to cell-extrinsic effects of endogenous P16410 and may be particularly important in the ability of DB01281 to treat chronic inflammatory disease . Differential expression of cyclophilin isoforms during keratinocyte differentiation . P62937 , the major intracellular binding protein for the immunosuppressive drug cyclosporin A ( DB00091 ) , was studied in human keratinocytes during differentiation both in vivo and in vitro . Analysis of cyclophilin by gel-filtration radiobinding-assay with tritiated DB00091 showed one specific radioactive peak at 17 kDa . By this technique , the levels of cyclophilin ( mean 55.23 +/- 8.43 pmol/mg protein ) did not significantly differ during keratinocyte differentiation . When the protein extracts from calcium-induced differentiating keratinocytes and normal human skin were analysed by PAGE radiobinding-assay , two specific radioactive DB00091 -binding peaks were detected . The major peak ( RF 0.13 ) was expressed in all samples ( mean 47.32 +/- 17.53 pmol/mg protein ) whereas the minor peak ( RF 0.23 ) was dramatically decreased about 6-fold in abnormally differentiated skin ( psoriasis ) as well as in non-differentiated keratinocytes . At least six [3H] DB00091 -binding isoforms with pI values ranging from 5.58 to 7.75 were detected by isoelectrofocusing autoradio-blotting-assay in normal human skin ; three of them immunoreacted with antibodies to cyclophilin . These results demonstrated the presence of several cyclophilin isoforms in human epidermal cells and an expression which correlated with the differentiation of human keratinocytes both in vivo and in vitro . DB11320 contributes to tissue remodeling via periostin expression . DB11320 is thought to have a critical role in the synthesis of extracellular matrix in skin and may be involved in tissue remodeling of allergic diseases . Recent studies revealed that periostin , a matricelluar protein , contributed to tissue remodeling ; however , a link between periostin and histamine remains unproven . We investigated whether periostin was involved in histamine-induced collagen production . Cultured dermal fibroblasts derived from wild-type ( WT ) or periostin knockout ( PN(-/-) ) mice were stimulated with histamine , and then collagen and periostin production was evaluated . DB11320 induced collagen gene expression in WT fibroblasts in the late phase but not in the early phase , whereas no effect on collagen expression was observed in histamine-stimulated PN(-/-) fibroblasts . In WT fibroblasts , histamine directly induced periostin expression in a dose-dependent manner , and an H1 receptor antagonist blocked both periostin and collagen expression . DB11320 activated extracellular signal-regulated kinase 1/2 ( P27361 /2 ) through the H1 receptor . Q15063 induction was inhibited by either H1 antagonist or P27361 /2 inhibitor treatment in vitro and was attenuated in P35367 (-/-) mice . Elevated expression of periostin was found in lesional skin from atopic dermatitis patients . These results suggest that histamine mediates periostin induction and collagen production through activation of the H1 receptor-mediated P27361 /2 pathway ; furthermore , histamine may accelerate the chronicity of atopic dermatitis . Knockdown endogenous CypA with siRNA in U2OS cells results in disruption of F-actin structure and alters tumor phenotype . P62937 ( CypA ) was originally identified as a cytosolic protein possessing peptidyl-prolyl isomerase activity . CypA has been shown to play a pivotal role in the immune response , but little is known about other molecular mechanisms of CypA-mediated biologic events . In our present study , we demonstrate that knockdown CypA expression using RNAi in U2OS cells resulted in disruption of the F-actin structure , as well as decreased anchorage-independent growth , proliferation , and migration . Wild-type U2OS cells treated with cyclosporine A ( DB00091 ) , a peptidyl-prolyl isomerase inhibitor , displayed the same phenotype as knockdown CypA cells , suggesting that the isomerase activity of CypA is required to maintain a normal phenotype . In vitro and in vivo binding assays revealed that CypA binds to O00401 , which functions in the nucleation of actin via the Arp2/3 complex . Pulse-chase labeling study indicated an enhanced degradation of O00401 in cell lacking CypA , suggesting that CypA is required for stabilizing O00401 to form a O00401 /Arp2/3 complex for the nucleation/initiation of F-actin polymerization . Transgenic mice overexpressing cyclophilin A are resistant to cyclosporin A-induced nephrotoxicity via peptidyl-prolyl cis-trans isomerase activity . DB00091 ( DB00091 ) suppresses immune reaction by inhibiting calcineurin activity after forming complex with cyclophilins and is currently widely used as an immunosuppressive drug . P62937 ( CypA ) is the most abundantly and ubiquitously expressed family member of cyclophilins . We previously showed that DB00091 toxicity is mediated by ROS generation as well as by inhibition of peptidyl-prolyl cis-trans isomerase ( PPIase ) activity of CypA in DB00091 -treated myoblasts [ FASEB J. 16 ( 2002 ) 1633 ] . Since DB00091 -induced nephrotoxicity is the most significant adverse effect in its clinical utilization , we here investigated the role of DB00091 inhibition of CypA PPIase activity in its nephrotoxicity using transgenic mouse models . Transgenic mice of either wild type ( CypA/wt ) or R55A PPIase mutant type ( CypA/R55A ) , a dominant negative mutant of CypA PPIase activity , showed normal growth without any apparent abnormalities . However , DB00091 -induced nephrotoxicity was virtually suppressed in CypA/wt mice , but exacerbated in CypA/R55A mice , compared to that of littermates . Also , life expectancy was extended in CypA/wt mice and shortened in CypA/R55A mice during DB00091 administration . Besides , DB00091 -induced nephrotoxicity was inversely related to the levels of catalase expression and activity . In conclusion , our data provide in vivo evidence that supplement of CypA PPIase activity allows animal 's resistance toward DB00091 -induced nephrotoxicity . Antiinflammatory effect of lactic acid bacteria : inhibition of cyclooxygenase-2 by suppressing nuclear factor-kappaB in Raw264.7 macrophage cells . Lactobacillus casei 3260 ( L. casei 3260 ) was evaluated in relation to the inflammatory response mediated by lipopolysaccharide ( LPS ) -induced nuclear factor-kappaB ( NF-kappaB ) and cyclooxygenase-2 ( P35354 ) expression in Raw264.7 macrophage cells . The treatment of Raw264.7 cells with L. casei 3260 significantly inhibited the secretion of tumor necrosis factor-alpha ( P01375 ) and prostaglandins E2 ( DB00917 ) , followed by suppression of P35354 . To clarify the molecular mechanism , the inhibitory effect of L. casei 3260 on the NF-kappaB signaling pathway was examined based on the luciferase reporter activity . Although the treatment of Raw264.7 cells with L. casei 3260 did not affect the transcriptional activity of NF-kappaB , it did inhibit NF-kappaB activation , as determined by the cytosolic p65 release and degradation of I-kappaBalpha . Therefore , these findings suggest that the suppression of P35354 through inhibiting the NF-kappaB activation by LPS may be associated with the antiinflammatory effects of L. casei 3260 on Raw264.7 cells . A cyclophilin A inducible expressed in gonad of zhikong scallop Chlamys farreri . P62937 ( CypA ) , a receptor for the immunosuppressive agent cyclosporin A ( DB00091 ) , is a cis-trans peptidyl-prolyl isomerase ( PPIase ) which accelerates the cis-trans isomerization of prolyl-peptide bonds , interacts with a variety of proteins and therefore regulates their activities . One CypA ( designated CfCypA ) cDNA was cloned from Chlamys farreri by expressed sequence tag ( EST ) and rapid amplification of cDNA ends ( RACE ) techniques . The full-length cDNA of CfCypA consisted of 1,248 nucleotides with a canonical polyadenylation signal sequence AATAAA , a poly ( A ) tail , and an open reading frame ( ORF ) of 495 nucleotides encoding a polypeptide of 164 amino acids . The deduced amino acid sequence shared high similarity with CypA from the other species , indicating that CfCypA should be a new member of the CypA family . Quantitative real-time ( RT ) PCR was employed to assess the mRNA expression of CfCypA in various tissues and its temporal expression in haemocytes and gonad of scallops challenged with Vibrio anguillarum . The mRNA transcripts of CfCypA could be detected in all the examined tissues with highest expression level in gonad . After bacterial challenge , the expression level of CfCypA was almost unchanged in haemocytes , but up-regulated in gonad and increased to the peak ( 22.59-fold ; P < 0.05 ) at 4 h post-injection , and then dropped to the original level at 8 h post-injection . These results indicated that CfCypA was constitutive expressed in haemocytes , but could be induced in gonad , and perhaps played a critical role in response to the bacterial challenge in gonad . Design and synthesis of conformationally constrained cyclophilin inhibitors showing a cyclosporin-A phenotype in C. elegans . P62937 ( CypA ) is a member of the immunophilin family of proteins and receptor for the immunosuppressant drug cyclosporin A ( DB00091 ) . Here we describe the design and synthesis of a new class of small-molecule inhibitors for CypA that are based upon a dimedone template . Electrospray mass spectrometry is utilised as an initial screen to quantify the protein affinity of the ligands . Active inhibitors and fluorescently labelled derivatives are then used as chemical probes for investigating the biological role of cyclophilins in the nematode Caenorhabditis elegans . P62937 -deficient mice are resistant to immunosuppression by cyclosporine . DB00091 is an immunosuppressive drug that is widely used to prevent organ transplant rejection . Known intracellular ligands for cyclosporine include the cyclophilins , a large family of phylogenetically conserved proteins that potentially regulate protein folding in cells . Immunosuppression by cyclosporine is thought to result from the formation of a drug-cyclophilin complex that binds to and inhibits calcineurin , a serine/threonine phosphatase that is activated by TCR engagement . Amino acids within the cyclophilins that are critical for binding to cyclosporine have been identified . Most of these residues are highly conserved within the 15 mammalian cyclophilins , suggesting that many are potential targets for the drug . We examined the effects of cyclosporine on immune cells and mice lacking Ppia , the gene encoding the prototypical cyclophilin protein cyclophilin A . TCR-induced proliferation and signal transduction by Ppia(-/-) P01730 (+) T cells were resistant to cyclosporine , an effect that was attributable to diminished calcineurin inhibition . Immunosuppressive doses of cyclosporine failed to block the responses of Ppia(-/-) mice to allogeneic challenge . Rag2(-/-) mice reconstituted with Ppia(-/-) splenocytes were also cyclosporine resistant , indicating that this property is intrinsic to Ppia(-/-) immune cells . Thus , among multiple potential ligands , CypA is the primary mediator of immunosuppression by cyclosporine . P35367 antagonist cetirizine impairs working memory processing speed , but not episodic memory . BACKGROUND AND PURPOSE : The histaminergic neurotransmitter system is currently under investigation as a target for drug treatment of cognitive deficits in clinical disorders . The therapeutic potential of new drugs may initially be screened using a model of histaminergic dysfunction , for example , as associated with the use of centrally active antihistamines . Of the selective second generation antihistamines , cetirizine has been found to have central nervous system effects . The aim of the present study was to determine whether cetirizine can be used as a tool to model cognitive deficits associated with histaminergic hypofunction . EXPERIMENTAL APPROACH : The study was conducted according to a three-way , double-blind , cross-over design . Treatments were single oral doses of cetirizine 10 and 20 mg and placebo . Effects on cognition were assessed using tests of word learning , memory scanning , vigilance , divided attention , tracking and visual information processing speed . KEY RESULTS : DB00341 10 mg impaired tracking performance and both doses impaired memory scanning speed . None of the other measures indicated impaired performance . CONCLUSION AND IMPLICATIONS : DB00341 affects information processing speed , but these effects were not sufficient to serve as a model for cognitive deficits in clinical disorders . [ DB00091 inhibits the adhesion of neutrophil with ECV-304 induced by hypoxia/reoxygenation via ROS- P62937 - P27361 /2 pathway ] . To investigate the inhibition of cyclosporin A ( DB00091 ) on neutrophil adhesion to human umbilical vein endothelial cells ( HUVECs , ECV-304 ) induced by hypoxia/reoxygenation and further explore its mechanism , a 1 h hypoxia/4 h reoxygenation model was reproduced using ECV-304 . The adhesion rate of neutrophils to ECV-304 was determined by measuring the activity of endogenous hexosaminidase . The expression of endothelial cell adhesion molecules of P16581 and P05362 was measured by flow cytometry . The expression of cyclophilin A ( CyPA ) and the activation of P27361 /2 was compared among experimental groups by Western blot . The content of reactive oxygen species ( ROS ) was measured by Fenton reaction . After being stimulated with 1 h hypoxia/4 h reoxygenation , ECV-304 showed an enhanced neutrophil adhensiveness in association with an increased surface expression of P16581 and P05362 . In parallel , the content of ROS was also increased . These effects were significantly suppressed by the addition of DB00091 . Most importantly , the expression of CyPA was significantly increased following 1 h hypoxia/4 h reoxygenation , which was accompanied with an increased activation of P27361 /2 . Treatment with CyPA inhibitor DB00091 and CyPA antisense oligonucleotides significantly inhibited the activation of P27361 /2 and decreased the adhesion of neutrophils to ECV-304 . The specific P27361 /2 inhibitor PD98059 caused an inhibition of neutrophil adhesion to hypoxia/reoxygenation-stimulated ECV-304 . Our data confirm that DB00091 inhibits neutrophil adhesion to hypoxia/reoxygenation stimulated ECV-304 by a mechanism involving inhibition of the signal transduction of ROS , CyPA and P27361 /2 . Cyclophilin interactions with incoming human immunodeficiency virus type 1 capsids with opposing effects on infectivity in human cells . P62937 ( CypA ) is a peptidyl-prolyl isomerase that binds to the capsid protein ( CA ) of human immunodeficiency virus type 1 ( HIV-1 ) and by doing so facilitates HIV-1 replication . Although CypA is incorporated into HIV-1 virions by virtue of CypA-Gag interactions that occur during virion assembly , in this study we show that the CypA-CA interaction that occurs following the entry of the viral capsid into target cells is the major determinant of CypA 's effects on HIV-1 replication . Specifically , by using normal and CypA-deficient Jurkat cells , we demonstrate that the presence of CypA in the target and not the virus-producing cell enhances HIV-1 infectivity . Moreover , disruption of the CypA-CA interaction with cyclosporine A ( DB00091 ) inhibits HIV-1 infectivity only if the target cell expresses CypA . The effect of DB00091 on HIV-1 infection of human cells varies according to which particular cell line is used as a target , and CA mutations that confer DB00091 resistance and dependence exert their effects only if target cells , and not if virus-producing cells , are treated with DB00091 . The differential effects of DB00091 on HIV-1 infection in different human cells appear not to be caused by polymorphisms in the recently described retrovirus restriction factor TRIM5alpha . We speculate that CypA and/or CypA-related proteins affect the fate of incoming HIV-1 capsid either directly or by modulating interactions with unidentified host cell factors . P62937 is an essential cofactor for hepatitis C virus infection and the principal mediator of cyclosporine resistance in vitro . DB00091 ( DB00091 ) and its derivatives potently suppress hepatitis C virus ( HCV ) replication . Recently , DB00091 -resistant HCV replicons have been identified in vitro . We examined the dependence of the wild-type and DB00091 -resistant replicons on various cyclophilins for replication . A strong correlation between DB00091 resistance and reduced dependency on cyclophilin A ( CyPA ) for replication was identified . Silencing of CyPB or CyPC expression had no significant effect on replication , whereas various forms of small interfering RNA ( siRNA ) directed at CyPA inhibited HCV replication of wild-type but not DB00091 -resistant replicons . The efficiency of a particular siRNA in suppressing CyPA expression was correlated with its potency in inhibiting HCV replication , and expression of an siRNA-resistant CyPA cDNA rescued replication . In addition , an anti-CyPA antibody blocked replication of the wild-type but not the resistant replicon in an in vitro replication assay . Depletion of CyPA alone in the DB00091 -resistant replicon cells eliminated DB00091 resistance , indicating that CyPA is the chief mediator of the observed DB00091 resistance . The dependency on CyPA for replication was observed for both genotype ( GT ) 1a and 1b replicons as well as a GT 2a infectious virus . An interaction between CyPA and HCV RNA as well as the viral polymerase that is sensitive to DB00091 treatment in wild-type but not in resistant replicons was detected . These findings reveal the molecular mechanism of DB00091 resistance and identify CyPA as a critical cellular cofactor for HCV replication and infection . DB04866 improves muscle-cell survival in muscular dystrophies . DB04866 has been shown to prevent fibrosis via the transforming growth factor-β/ P84022 pathway in muscular dystrophies . We hypothesized that halofuginone would reduce apoptosis -- the presumed cause of satellite-cell depletion during muscle degradation-in the mdx mouse model of Duchenne muscular dystrophy . Six-week-old mdx mouse diaphragm exhibited fourfold higher numbers of apoptotic nuclei compared with wild-type mice as determined by a TUNEL assay . Apoptotic nuclei were found in macrophages and in Pax7-expressing cells ; some were located in centrally-nucleated regenerating myofibers . DB04866 treatment of mdx mice reduced the apoptotic nuclei number in the diaphragm , together with reduction in Bax and induction in Bcl2 levels in myofibers isolated from these mice . A similar effect was observed when halofuginone was added to cultured myofibers . No apparent effect of halofuginone was observed in wild-type mice . Inhibition of apoptosis or staurosporine-induced apoptosis by halofuginone in mdx primary myoblasts and P06681 myogenic cell line , respectively , was reflected by less pyknotic/apoptotic cells and reduced Bax expression . This reduction was reversed by a phosphinositide-3-kinase and mitogen-activated protein kinase/extracellular signal-regulated protein kinase inhibitors , suggesting involvement of these pathways in mediating halofuginone 's effects on apoptosis . DB04866 increased apoptosis in α smooth muscle actin- and prolyl 4-hydroxylase β-expressing cells in mdx diaphragm and in myofibroblasts , the major source of extracellular matrix . The data suggest an additional mechanism by which halofuginone improves muscle pathology and function in muscular dystrophies . P62937 is required for P61073 -mediated nuclear export of heterogeneous nuclear ribonucleoprotein A2 , activation and nuclear translocation of P27361 /2 , and chemotactic cell migration . The chemokine receptor P61073 -mediated signaling cascades play an important role in cell proliferation and migration , but the underlying mechanisms by which the receptor signaling is regulated remain incompletely understood . Here , we demonstrate that P61073 was co-immunoprecipitated with cyclophilin A ( CyPA ) from the lysate of HEK293 cells stably expressing P61073 . Although both the glutathione S-transferase- P61073 N- and C-terminal fusion proteins were associated with the purified CyPA , truncation of the C-terminal domain of P61073 robustly inhibited the receptor co-immunoprecipitation with CyPA in intact cells , thereby suggesting a critical role of the receptor C terminus in this interaction . Ligand stimulation of P61073 induced CyPA phosphorylation and nuclear translocation , both of which were inhibited by truncation of the C-terminal domain of P61073 . CyPA was associated with transportin 1 , and knockdown of transportin 1 by RNA interference ( RNAi ) blocked P48061 -induced nuclear translocation of CyPA , thereby suggesting a transportin 1-mediated nuclear import of CyPA . CyPA formed a complex with heterogeneous nuclear ribonucleoprotein ( hnRNP ) A2 , which underwent nuclear export in response to activation of P61073 . Interestingly , the P61073 -mediated nuclear export of hnRNP A2 was blocked by RNAi of CyPA . Moreover , P61073 -evoked activation of extracellular signal-regulated kinase 1/2 ( P27361 /2 ) was attenuated by CyPA RNAi , by overexpression of a PPIase-deficient mutant of CyPA ( CyPA-R55A ) , and by pretreatment of the immunosuppressive drugs , cyclosporine A and sanglifehrin A . Finally , P48061 -induced chemotaxis of HEK293 cells stably expressing P61073 or Jurkat T cells was inhibited by CyPA RNAi or DB00091 treatment . P62937 and nuclear factor of activated T cells are essential in cyclosporine-mediated suppression of polyomavirus BK replication . Immunosuppressants have impacts on the development of polyomavirus-associated nephropathy . We previously demonstrated that cyclosporin A ( DB00091 ) suppressed polyomavirus BK ( BKV ) replication . The role of cyclophilin A ( CypA ) and nuclear factor of activated T cells ( NFAT ) in DB00091 -imposed suppression of BKV replication was determined in this study . Results demonstrated that knockdown of CypA but not CypB significantly reduced BKV large T antigen ( TAg ) expression and BKV titer . Overexpression of CypA reversed CypA siRNA-induced inhibition in BKV TAg expression . In addition , CypA overexpression attenuated the suppressive effect of DB00091 on TAg expression , suggesting CypA implicated in DB00091 -mediated anti-BKV effect . Knockdown of Q12968 abrogated TAg expression , while overexpression of Q12968 promoted TAg expression and augmented BKV promoter activity . Q12968 binding to the BKV promoter was verified by chromatin immunoprecipitation assay and electrophoretic mobility shift assay . Renal histology also displayed an increase in Q12968 expression in tubulointerstitium of BKV-associated nephropathy . Furthermore , overexpression of Q12968 rescued DB00091 -mediated inhibition of BKV load and TAg expression . A DB00091 analog , NIM811 , which can not block NFAT functionality , failed to suppress TAg expression . In conclusion , CypA and NFAT are indispensable in BKV replication . DB00091 inhibits BKV replication through CypA and NFAT , which may be potential targets of anti-BKV treatment . P62937 modulates the sensitivity of HIV-1 to host restriction factors . Many mammalian species express restriction factors that confer host resistance to retroviral infection . Here we show that HIV-1 sensitivity to restriction factors is modulated by cyclophilin A ( CypA ) , a host cell protein that binds the HIV-1 capsid protein ( CA ) . In certain nonhuman primate cells , the CA-CypA interaction is essential for restriction : HIV-1 infectivity is increased > 100-fold by cyclosporin A ( DB00091 ) , a competitive inhibitor of the interaction , or by an HIV-1 CA mutation that disrupts CypA binding . Conversely , disruption of CA-CypA interaction in human cells reveals that CypA protects HIV-1 from the Ref-1 restriction factor . These findings suggest that HIV-1 has co-opted a host cell protein to counteract restriction factors expressed by human cells and that this adaptation can confer sensitivity to restriction in unnatural hosts . Manipulation of HIV-1 CA recognition by restriction factors promises to advance animal models and new therapeutic strategies for HIV-1 and AIDS . P62937 and calcineurin functions investigated by gene inactivation , cyclosporin A inhibition and cDNA arrays approaches in the phytopathogenic fungus Botrytis cinerea . Calcineurin phosphatase and cyclophilin A are cellular components involved in fungal morphogenesis and virulence . Their roles were investigated in the phytopathogenic fungus Botrytis cinerea using gene inactivation , drug inhibition and cDNA macroarrays approaches . First , the BCP1 gene coding for cyclophilin A was identified and inactivated by homologous recombination . The bcp1Delta null mutant obtained was still able to develop infection structures but was altered in symptom development on bean and tomato leaves . Opposite to this , calcineurin inhibition using cyclosporin A ( DB00091 ) modified hyphal morphology and prevented infection structure formation . DB00091 drug pattern signature on macroarrays allowed the identification of 18 calcineurin-dependent ( CND ) genes among 2839 B. cinerea genes . Among the co-regulated CND genes , three were shown to be organized as a physical cluster that could be involved in secondary metabolism . The signature of BCP1 inactivation on macroarrays allowed the identification of only three BCP1 cyclophilin-dependent ( O75976 ) genes that were different from CND genes . Finally , no DB00091 drug pattern signature was observed in the bcp1Delta null mutant which provided a molecular target validation of the drug . DB00741 is a suppressor of apoptosis in bovine corpus luteum . Glucocorticoid ( GC ) acts as a modulator of physiological functions in several organs . In the present study , we examined whether GC suppresses luteolysis in bovine corpus luteum ( CL ) . DB00741 ( an active GC ) reduced the mRNA expression of caspase 8 ( Q14790 ) and caspase 3 ( P42574 ) and reduced the enzymatic activity of P42574 and cell death induced by tumor necrosis factor ( P01375 ) and interferon gamma ( P01579 ) in cultured bovine luteal cells . mRNAs and proteins of GC receptor ( P04150 ) , 11beta-hydroxysteroid dehydrogenase type 1 ( P28845 ) , and P80365 were expressed in CL throughout the estrous cycle . Moreover , the protein expression and the enzymatic activity of P28845 were high at the early and the midluteal stages compared to the regressed luteal stage . These results suggest that cortisol suppresses P01375 - P01579 -induced apoptosis in vitro by reducing apoptosis signals via Q14790 and P42574 in bovine CL and that the local increase in cortisol production resulting from increased P28845 at the early and midluteal stages helps to maintain CL function by suppressing apoptosis of luteal cells . Contribution of P62937 to determination of simian immunodeficiency virus tropism : a progress update . An understanding of cellular factors that affect viral replication contributes to elucidation of the mechanism for the determination of viral tropism . P62937 ( CypA ) , a peptidyl-prolyl cis-trans isomerase ( PPIase ) , is an essential host factor for the efficient replication of human immunodeficiency virus type 1 ( HIV-1 ) in human cells . However , its role in simian immunodeficiency virus ( SIV ) replication has not been determined . In the 2008 US-Japan AIDS panel meeting , I have presented the effect of cyclosporine A ( DB00091 ) , a PPIase inhibitor , on replication of wild-type SIV . Interestingly , DB00091 treatment enhanced SIV replication in human cells but abrogated SIV replication in macaque cells , implying a species-specific effect of DB00091 on SIV replication . After this meeting , analysis using CypA knocked-down human cells indicated that CypA was considered inhibitory for SIV replication . These results suggest possible involvement of CypA in the determination of SIV tropism . Q92731 mediates increased activation of PI3K/Akt signaling and improved myocardial function in female hearts following acute ischemia . Females have a lower incidence of heart failure and improved survival after myocardial ischemia-reperfusion ( I/R ) compared with males . Although estrogen-suppressed cardiomyocyte apoptosis may be mediated through the phosphatidylinositol 3-kinase ( PI3K ) /protein kinase B ( Akt ) pathway , it is unclear whether this action is mediated via estrogen receptor beta ( ERbeta ) . Therefore , we hypothesized that ERbeta mediates estrogen-induced cardioprotection through PI3K/Akt and antiapoptotic signaling in females but not in males . Isolated male and female hearts from ERbeta knockout ( ERbetaKO ) and wild-type ( WT ) mice ( n = 5 mice/group ) were subjected to 20-min ischemia followed by 60-min reperfusion ( Langendorff ) . Ablation of ERbeta significantly decreased postischemic recovery of left ventricular developed pressure in female , but not male , hearts . Reduced activation of PI3K and Akt was noted in female ERbetaKO hearts , which was associated with increased expression of caspase-3 and -8 , as well as decreased Bcl-2 levels compared with WT . However , myocardial P40763 , O14543 ( suppressor of cytokine signaling 3 ) , P15692 , and P01375 receptors 1 and 2 levels did not change in ERbetaKO of either sex following I/R . Furthermore , deficiency of ERbeta increased myocardial JNK activation in females but increased P27361 /2 activity in males during acute I/R . We conclude that ERbeta mediates myocardial protection via upregulation of PI3K/Akt activation , decreased caspase-3 and -8 , and increased Bcl-2 in female hearts following I/R . These findings provide evidence of ERbeta-mediated PI3K/Akt and antiapoptotic signaling in the myocardium and may lend insight into the mechanistic pathways behind the observed variation in clinical outcomes between males and females after myocardial infarction . Cyclophilin inhibitors as a novel HCV therapy . A critical role of Cyclophilins , mostly P62937 ( CyPA ) , in the replication of HCV is supported by a growing body of in vitro and in vivo evidence . CyPA probably interacts directly with nonstructural protein 5A to exert its effect , through its peptidyl-prolyl isomerase activity , on maintaining the proper structure and function of the HCV replicase . The major proline substrates are located in domain II of NS5A , centered around a " DY " dipeptide motif that regulates CyPA dependence and DB00091 resistance . Importantly , DB00091 A derivatives that lack immunosuppressive function efficiently block the CyPA-NS5A interaction and inhibit HCV in cell culture , an animal model , and human trials . Given the high genetic barrier to development of resistance and the distinctness of their mechanism from that of either the current standard of care or any specifically targeted antiviral therapy for HCV ( P35610 -C ) , CyP inhibitors hold promise as a novel class of anti-HCV therapy . Postprandial cell defense system responses to meal formulations : stratification through gene expression profiling . SCOPE : Cell defenses regulating homeostatic control of postprandial stress are influenced by interindividual variation , food composition and health status . This study investigates effects of food composition on individual postprandial responses and associations with health . METHODS AND RESULTS : Volunteers ( n = 16 ) consumed four food formulations ( 50 % unsaturated/saturated fat , with/without beetroot extract 10 g/100 g ) on separate occasions . GeXP assay measured whole blood postprandial gene expression profiles of 28 cell defense markers at baseline and postprandial time points 1 , 2 , 4 , 6 , 24 h . Plasma markers of metabolic lipids , hormones , inflammatory cytokines , oxidative stress , and DNA damage/repair were also assessed . SIRT 1 , P55851 , P09601 , P48637 , P35354 , P04637 , CDKN2A , P62937 , O14543 , and P27695 expression profiles revealed distinct stratified subgroups associated with plasma HDLs , P01375 -α and postprandial responses of O14543 , and P62937 . Leptin , P05231 , and DNA strand breaks revealed differing responses to fat type consumed . CONCLUSION : This study demonstrates postprandial immune , inflammatory , redox , metabolic , and DNA repair responses that are largely independent of fat type consumed ( unsaturated/saturated ) or addition of beetroot extract , in apparently healthy individuals . However , postprandial responses can be characterized by regulation of gene expression associated with markers linked to health status and are subject to interindividual variation that can influence postprandial responses . Design and synthesis of a rapamycin-based high affinity binding P62942 ligand . BACKGROUND : The immunosuppressants rapamycin , ascomycin , FK506 , and cyclosporin act by binding to a class of cytosolic proteins , the immunophilins . In the case of FK506 , ascomycin and cyclosporin , the target of the immunophilin-immunosuppressant complex is calcineurin ; in the case of rapamycin , the target is P42345 ( TOR/ P42345 ) . DB00877 , ascomycin and FK506 have a common domain responsible for binding to P62942 , their cellular receptor , and different effector domains that determine the target of the complex . Both domains are necessary for signal transduction and biological activity . RESULTS : A hybrid molecule containing the rapamycin-FK506-ascomycin binding domain and a peptide tether has been designed , synthesized and biologically evaluated . The designed compound binds to P62942 with high affinity but has no biological activity , as expected from its lack of an effector domain . CONCLUSIONS : The designed rapamycin-based P62942 ligand exhibits powerful binding properties but , unlike rapamycin , shows no activity in P05231 dependent B-cell proliferation and , in contrast to FK506 , shows no activity in the P60568 reporter assay . The modular nature of this designed molecule should make it possible to generate a series of compounds with effector domains for targeting either calcineurin or P42345 ( TOR/ P42345 ) or both , as potential biological tools and immunosuppressive agents . Discovering novel chemical inhibitors of human cyclophilin A : virtual screening , synthesis , and bioassay . P62937 ( CypA ) is a member of cyclophilins , a family of the highly homologous peptidyl prolyl cis-trans isomerases ( PPIases ) , which can bind to cyclosporin A ( DB00091 ) . CypA plays critical roles in various biological processes , including protein folding , assembly , transportation , regulation of neuron growth , and HIV replication . The discovery of CypA inhibitor is now of a great special interest in the treatment of immunological disorders . In this study , a series of novel small molecular CypA inhibitors have been discovered by using structure-based virtual screening in conjunction with chemical synthesis and bioassay . The SPECS_1 database containing 85,000 small molecular compounds was searched by virtual screening against the crystal structure of human CypA . After SPR-based binding affinity assay , 15 compounds were found to show binding affinities to CypA at submicro-molar or micro-molar level ( compounds 1-15 ) . Seven compounds were selected as the starting point for the further structure modification in considering binding activity , synthesis difficulty , and structure similarity . We thus synthesized 40 new small molecular compounds ( 1-6 , 15 , 16a-q , 17a-d , and 18a-l ) , and four of which ( compounds 16b , 16h , 16k , and 18g ) showed high CypA PPIase inhibition activities with IC50s of 2.5-6.2 microM . Pharmacological assay indicated that these four compounds demonstrated somewhat inhibition activities against the proliferation of spleen cells . Two cyclophilin A homologs with shared and distinct functions important for growth and virulence of Cryptococcus neoformans . P62937 is the target of the immunosuppressant cyclosporin A ( DB00091 ) and is encoded by a single unique gene conserved from yeast to humans . In the pathogenic fungus Cryptococcus neoformans , two homologous linked genes , P15085 and P48052 , were found to encode two conserved cyclophilin A proteins . In contrast to Saccharomyces cerevisiae , in which cyclophilin A mutations confer DB00091 resistance but few other phenotypes , cyclophilin A mutations conferred dramatic phenotypes in C. neoformans . The Cpa1 and Cpa2 cyclophilin A proteins play a shared role in cell growth , mating , virulence and DB00091 toxicity . The Cpa1 and Cpa2 proteins also have divergent functions . cpa1 mutants are inviable at 39 degrees C and attenuated for virulence , whereas cpa2 mutants are viable at 39 degrees C and fully virulent . cpa1 cpa2 double mutants exhibited synthetic defects in growth and virulence . P62937 active site mutants restored growth of cpa1 cpa2 mutants at ambient but not at higher temperatures , suggesting that the prolyl isomerase activity of cyclophilin A has an in vivo function . P62937 interacts with domain II of hepatitis C virus NS5A and stimulates RNA binding in an isomerase-dependent manner . NS5A plays a critical , yet poorly defined , role in hepatitis C virus genome replication . The protein consists of three domains , each of which is able to bind independently to the 3' untranslated region ( UTR ) of the viral positive strand genomic RNA . The peptidyl-prolyl isomerase cyclophilin A ( CypA ) binds to domain II , catalyzing cis-trans isomerization . CypA inhibitors such as cyclosporine ( DB00091 ) have been shown to inhibit hepatitis C virus ( HCV ) replication . We show here that CypA stimulated domain II RNA binding activity , and this stimulation was abrogated by DB00091 . An isomerase mutant of CypA ( H126Q ) failed to bind to domain II and did not stimulate RNA binding . Finally , we demonstrate that the RNA binding of two domain II mutants , the D316E and D316E/Y317N mutants , previously shown to exhibit CypA independence for RNA replication , was unaffected by CypA . This study provides an insight into the molecular mechanism of CypA activity during HCV replication and further validates the use of CypA inhibitors in HCV therapy . Modulation of ryanodine receptor Ca2+ channels ( Review ) . Ryanodine-sensitive Ca2+ release channels ( ryanodine receptors , RyRs ) play a crucial role in the mobilization of Ca2+ from the sarcoplasmic reticulum ( SR ) during the excitation-contraction coupling of muscle cells . In skeletal muscle , depolarization of transverse tubules activates the RyR , whereas in cardiac muscle , a Ca2+ influx through an L-type Ca2+ channel activates the RyR . The RyR is also activated by caffeine , a low concentration ( < 10 µM ) of ryanodine or cyclic ADP-ribose . RyR activity is inhibited by Mg2+ , ruthenium red , or higher concentrations ( ≥100 µM ) of ryanodine . The activity of RyR channels is modulated by phosphorylation and by associated proteins , including calmodulin ( P62158 ) , calsequestrin ( CSQ ) and FK506-binding proteins ( FKBPs ) . In muscle cells , apoCaM ( Ca2+-free P62158 ) activates the RyR channel , and Ca2+ P62158 ( Ca2+-bound P62158 ) inhibits the channel . CSQ can bind approximately 40 moles of Ca2+/mole of CSQ in the SR lumen of muscle cells , and interacts functionally with RyR protein . When the RyR is stimulated , Ca2+ released from the lumen is dissociated from the CSQ- Ca2+ complex . A 12-kDa or 12.6-kDa FK506-binding protein ( P62942 or P68106 , respectively ) is associated with RyR protein . When P62942 or P68106 is dissociated from the FKBP-RyR complex , the RyR is modulated ( activated ) . Phosphorylation of the RyR by DB02527 -dependent protein kinase ( PKA ) and Ca2+/calmodulin-dependent protein kinase II modulates the channel . PKA phosphorylation of the RyR on the skeletal and cardiac muscle SR dissociates P62942 or P68106 from the RyR complex . This review deals with the modulation mechanisms of RyR proteins by associated proteins and phosphorylation . HCV NS5A and Q00978 compete for CypA binding . BACKGROUND & AIMS : P62937 ( CypA ) is vital for HCV replication . Cyp inhibitors successfully decrease viral loads in HCV-infected patients . However , their mechanisms of action remain unknown . Since interferon ( IFN ) can also suppress HCV replication , we asked whether a link between CypA and the IFN response exists . METHODS : We used cellular and recombinant pulldown approaches to investigate the possibility of a specific association of CypA with host ligands . RESULTS : We found for the first time that CypA binds to a major component of the IFN response - the IFN regulatory factor 9 ( Q00978 ) . Q00978 is the DNA-binding component of the transcriptional IFN-stimulated gene factor 3 ( ISGF3 ) . CypA binds directly to Q00978 via its peptidyl-prolyl isomerase ( PPIase ) pocket . Cyp inhibitors such as cyclosporine A ( DB00091 ) or non-immunosuppressive derivates such as alisporivir and SCY-635 , prevent Q00978 -CypA complex formation . CypA binds to the C-terminal Q969Q1 -association-domain ( IAD ) , but not to the DNA-binding or linker domains of Q00978 . Remarkably , CypA associates with the multimeric ISGF3 complex . We also obtained evidence that CypA neutralization enhances IFN-induced transcription . Interestingly , the hepatitis C virus ( HCV ) non-structural 5A ( NS5A ) protein , which is known to modulate the IFN response , competes with Q00978 for CypA binding and can prevent the formation of Q00978 -CypA complexes . CONCLUSIONS : This study demonstrates for the first time that CypA binds specifically to a component of the Janus kinase/signal transducer and activator of transcription ( JAK/ P35610 ) pathway , Q00978 . This study also reveals a novel opportunity of HCV to modulate the IFN response via NS5A . Novel roles of Akt and P42345 in suppressing TGF-beta/ P36897 -mediated P84022 activation . P01308 -like growth factor-I inhibits transforming growth factor-beta ( TGF-beta ) signaling by blocking activation of P84022 ( S3 ) , via a phosphatidylinositol 3-kinase ( PI3K ) /Akt-dependent pathway . Here we provide the first report that the kinase activity of Akt is necessary for its ability to suppress many TGF-beta responses , including S3 activation and induction of apoptosis . Wild-type and myristoylated Akts ( Akt(WT) and Akt(Myr) ) suppress TGF-beta-induced phospho-activation of S3 but not Q15796 ( S2 ) , whereas kinase-dead Akt1 ( Akt1K179M ) or dominant-negative PI3K enhances TGF-beta-induced phospho-activation of both S2 and S3 . Using siRNA , rapamycin ( Rap ) , and adenoviral expression for P62942 -resistant and constitutively active P36897 ( P36897 ) , we demonstrate that mammalian target of Rap ( P42345 ) mediates Akt1 suppression of phospho-activation of S3 . These and further data on Akt1-S3 binding do not support a recently proposed model that Akt blocks S3 activation through physical interaction and sequestration of S3 from TGF-beta receptors . We propose a novel model whereby Akt suppresses activation of S3 in an Akt kinase-dependent manner through P42345 , a likely route for loss of tumor suppression by TGF-beta in cancers . Nephrotoxicity of cyclosporin A and FK506 : inhibition of calcineurin phosphatase . DB00091 ( DB00091 ; 50 mg/kg ) and Fujimycine ( FK506 ; 5 mg/kg ) , but not the related macrolide immunosuppressant rapamycin ( 5 mg/kg ) , caused a reduction of glomerular filtration rate , degenerative changes of proximal tubular epithelium , and hypertrophy of the juxtaglomerular apparatus in male Wistar rats when given for 10 days . The molecular mechanisms of DB00091 and FK506 toxicity were investigated . P62937 and FK506-binding protein , the main intracytoplasmic receptors for DB00091 and FK506 , respectively , were each detected in renal tissue extract . In the kidney , high levels of immunoreactive and enzymatically active calcineurin were found which were inhibited by the immunosuppressants DB00091 and FK506 , but not by rapamycin . Finally , specific immunophilin-drug-calcineurin complexes formed only in the presence of DB00091 and FK506 , but not rapamycin . These results suggest that the nephrotoxic effects of DB00091 and FK506 is likely mediated through binding to renal immunophilin and inhibiting calcineurin phosphatase . P62937 may contribute to the inflammatory processes in rheumatoid arthritis through induction of matrix degrading enzymes and inflammatory cytokines from macrophages . P62937 ( CypA ) levels increase in the sera and synovial fluids of rheumatoid arthritis ( RA ) patients , but the cell types expressing CypA and the function of CypA in the pathogenesis of RA are not known yet . Immunohistochemistry analyses revealed high level CypA staining in the macrophages in the lining layers of human RA and osteoarthritis synovium . Low level CypA staining was also detected in endothelial cells , lymphocytes , and smooth muscle cells in RA synovium . Further investigation of the CypA function using monocyte/macrophage cell lines revealed that CypA induced expression of cytokine/chemokines such as P01375 , P10145 , P13500 , and IL-1beta and matrix metalloproteinase ( MMP ) -9 through a pathway that is dependent on NFkappaB activation . Furthermore , P14780 staining pattern overlapped with that of CypA in both RA and OA synovium . Our data suggest that CypA may stimulate macrophages to degrade joint cartilage via P14780 expression and promote inflammation via pro-inflammatory cytokine secretion . HIV protease substrate conformation : modulation by cyclophilin A . P62937 ( CyPA ) , a cytosolic peptidyl-prolyl trans-cis isomerase can accelerate the trans-cis isomerization of Xxx-Pro peptide bonds . One- and two-dimensional 1H-NMR spectroscopy were used to determine that the heptapeptide DB00133 -Gln- DB00174 - DB00135 -Pro- DB00167 - DB00161 , a model peptide of an HIV-1 protease cleavage site in the gag polyprotein of HIV-1 , is a substrate for CyPA . Experiments revealed a slow exchange about the DB00135 -Pro peptide bond with 30 +/- 5 % in the cis conformation ( pH 1-9 ) . While the interconversion rate is too slow to measure by kinetic NMR methods in the absence of CyPA , these methods , saturation transfer and NOE experiments , established that CyPA enhanced the rate of trans-cis interconversion , a process inhibited by cyclosporin A ( DB00091 ) . With a substrate:CyPA ratio of 40:1 , an interconversion rate of 2.5 s(-1) at 25 degrees C was observed . Inhibition of histamine H1 receptor activity modulates proinflammatory cytokine production of dendritic cells through c-Rel activity . BACKGROUND : DB11320 exerts diverse effects on immune regulation through four types of histamine receptors ( HRs ) . Among them , type 1 receptor ( P35367 ) plays an important role in allergic inflammation . Dendritic cells ( DCs ) , which express at least three types of HRs , are professional antigen-presenting cells controlling the development of allergic inflammation . However , the molecular mechanisms involved in P35367 -mediated NF-ĸB signaling of DCs remain poorly defined . METHODS : Bone-marrow ( BM ) -derived DCs ( BM-DCs ) were treated with P35367 inverse agonists to interrupt basal P35367 -mediated signaling . The crosstalk of P35367 -mediated signaling and the NF-ĸB pathway was examined by NF-ĸB cellular activity using a luciferase reporter assay , NF-ĸB subunit analysis using Western blotting and P01375 -α promoter activity using chromatin immunoprecipitation . RESULTS : Blockage of P35367 signaling by inverse agonists significantly inhibited P01375 -α and P05231 production of BM-DCs . P35367 -specific agonists were able to enhance P01375 -α production , but this overexpression was significantly inhibited by NF-ĸB inhibitor . The P35367 inverse agonist ketotifen also suppressed cellular NF-ĸB activity , suggesting crosstalk between P35367 and NF-ĸB signaling in DCs . After comprehensive analysis of NF-ĸB subunits , c-Rel protein expression was significantly down-regulated in ketotifen-treated BM-DCs , which led to inhibition of the promoter activity of P01375 -α . Finally , adoptive transfer of the ketotifen-treated BM-DCs did not induce significant allergic airway inflammation compared to that of control cells in vivo . CONCLUSIONS : Our results suggest that c-Rel controls P35367 -mediated proinflammatory cytokine production in DCs . This study provides a potential mechanism of P35367 -mediated signaling and NF-ĸB pathway crosstalk in allergic inflammation . DB01098 , a new P04035 inhibitor , reduces the colonic inflammatory response in dextran sulfate sodium-induced colitis in mice . The aim of the present study was to elucidate the beneficial effects of rosuvastatin , a new P04035 inhibitor , on colonic mucosal damage and on the inflammatory response in a dextran sulfate sodium ( DSS ) colitis model . Acute colitis was induced using 8 % DSS in female BALB/c mice . Colonic mucosal inflammation was evaluated clinically , biochemically , and histologically . Mucosal protein contents and mRNA levels of tumor necrosis factor ( P01375 ) -alpha were determined by immunoassay and real time-PCR . The mRNA levels of endothelial nitric oxide synthase ( P29474 ) were determined by real-time PCR . Disease activity scores in DSS-induced colitis model mice , as determined by weight loss , stool consistency , and blood in stool , were significantly lower in the rosuvastatin-treated mice than in control mice . Shortening of the colon was significantly reversed by rosuvastatin . Increases in tissue-associated myeloperoxidase activity and thiobarbituric acid-reactive substances after DSS administration were both significantly inhibited by treatment with rosuvastatin . DB01098 also inhibited increases in intestinal P01375 protein and mRNA expression after DSS administration , respectively . The mucosal mRNA levels of P29474 were decreased after DSS administration , but preserved in mice treated with rosuvastatin . These results suggest that rosuvastatin prevents the development of DSS-induced colitis in mice via the inhibition of mucosal inflammatory responses associated with the preservation of P29474 transcription . DB00091 regulates the levels of cyclophilin A in neuroblastoma cells in culture . P62937 ( CyP-A ) , a member of a highly conserved family of proteins , immunophilins , is the major intracellular receptor for the immunosuppressive drug , cyclosporin A ( DB00091 ) . CyP-A is widely expressed in many tissues , but is found in the highest concentration in brain tissues and may perform critical neuronal functions . DB00091 is a known neurotoxin . Therefore , understanding the regulation of CyP-A levels in nerve cells , particularly by DB00091 , is important . We have utilized murine neuroblastoma ( NB ) cells as an experimental model to investigate this issue . Our results show that DB00091 alone was sufficient to induce morphological differentiation in undifferentiated NB cells and to increase CyP-A levels as determined by immunostaining . However , inducing terminal differentiation by elevating adenosine 3',5'-cyclic monophosphate ( DB02527 ) levels using either 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone ( RO20-1724 ) , an inhibitor of cyclic nucleotide phosphodiesterase , or prostaglandin E1 ( PGE1 ) , a stimulator of adenylate cyclase , was not sufficient to increase CyP-A levels . DB00091 was required to increase CyP-A levels in both RO20-1724- and PGE1-induced differentiated NB cells . Increases in CyP-A levels , however , occurred without any change in the expression of the CyP-A gene as determined by reverse-transcriptase polymerase-chain reaction analysis using ( CyP-A ) -specific primers . These results suggest that DB00091 regulates the level of its own binding protein , CyP-A , in both undifferentiated and DB02527 -induced differentiated NB cells in culture . Proangiogenesis action of the thyroid hormone analog 3,5-diiodothyropropionic acid ( DITPA ) is initiated at the cell surface and is integrin mediated . We have recently described the proangiogenesis effects of thyroid hormone in the chick chorioallantoic membrane ( P62158 ) model . Generation of new blood vessels from existing vessels was promoted 2- to 3-fold by either T(4) or T(3) at 10(-8)-10(-7) M total hormone concentrations . In the present studies , nanomolar concentrations of 3,5-diiodothyropropionic acid ( DITPA ) , a thyroid hormone analog with inotropic but not chronotropic properties , exhibited potent proangiogenic activity that was comparable to that obtained with T(3) and T(4) in both the P62158 model and in an in vitro three-dimensional human microvascular endothelial sprouting assay . The proangiogenesis effect of DITPA was inhibited by tetraiodothyroacetic acid , a thyroid hormone analog that competes with T(4) and T(3) for a novel cell surface hormone receptor site on integrin alphavbeta3 . The thyroid hormone analogs DITPA , T(4) , and T(4)-agarose , as well as basic fibroblast growth factor ( b-FGF ) and vascular endothelial cell growth factor , demonstrated comparable proangiogenic effects in the P62158 model and in the three-dimensional human microvascular endothelial sprouting model . The proangiogenesis effect of either DITPA or b-FGF was blocked by PD 98059 , an inhibitor of the P27361 /2 signal transduction cascade . Additionally , a specific integrin alphavbeta3 small molecule antagonist , XT199 , effectively inhibited the proangiogenesis effect of DITPA and b-FGF . Thus , the proangiogenesis actions of thyroid hormone and its analog DITPA are initiated at the plasma membrane , apparently at integrin alphavbeta3 , and are MAPK dependent . Altered regulation of renal nitric oxide , atrial natriuretic peptide and cyclooxygenase systems in aldosterone escape in rats . The present study was aimed to determine whether there is an altered role of local nitric oxide ( NO ) , atrial natriuretic peptide ( P01160 ) and cyclooxygenase ( P36551 ) systems in the kidney in association with the aldosterone escape . Male Sprague-Dawley rats were used . DB04630 ( 200 microg/day ) was infused through entire time course . The control group was kept on a low sodium diet ( 0.02 mEq/day ) , and the experimental group was supplied with a higher sodium diet ( 2. /day ) . Four days after beginning the regimen , the kidneys were taken . The protein expression of NO synthase ( NOS ) and P36551 isoforms was determined by semiquantitative immunoblotting . The mRNA expression of components of P01160 system was determined by real-time polymerase chain reaction . The activities of soluble and particulate guanylyl cyclases were determined by the amount of cGMP generated in responses to sodium nitroprusside and P01160 , respectively . There developed aldosterone escape in the experimental group . Accordingly , the renal content and the urinary excretion of NO increased . The expression of P29475 was increased in the inner medulla . Neither the expression of P29474 nor that of P35228 was changed . The expression and the catalytic activity of soluble guanylyl cyclase remained unaltered . The mRNA expression of P01160 was increased . Neither the expression of P16066 or P17342 nor the activity of particulate guanylyl cyclase was altered in the papilla . The protein expression of P35354 was increased in the inner medulla , while that of P23219 remained unchanged . In conclusion , the upregulation of P29475 , P01160 , and P35354 may be causally related with the aldosterone escape . P62937 facilitates translocation of the Clostridium botulinum P06681 toxin across membranes of acidified endosomes into the cytosol of mammalian cells . The binary Clostridium botulinum P06681 toxin consists of the binding/translocation component C2IIa and the separate enzyme component C2I , which mono-ADP-ribosylates actin in eukaryotic cells . Pore formation of C2IIa in early endosomal membranes facilitates translocation of unfolded C2I into the cytosol . We discovered earlier that translocation of C2I depends on the activity of the host cell chaperone heat shock protein Hsp90 . Here , we demonstrate that cyclosporin A , which inhibits the peptidyl-prolyl cis/trans isomerase activity of cyclophilins , inhibited intoxication of cells with P06681 toxin and prevented uptake of C2I into the cytosol . DB00091 blocked the pH-dependent translocation of C2I activity across membranes of intact cells and of partially purified early endosomes . In vitro , the addition of cytosol to P06681 toxin-loaded endosomes induced translocation of C2I activity into the cytosol , which was prevented by pretreatment of the cytosol with an antibody against cyclophilin A . Pull-down experiments with lysates from P06681 toxin-treated cells revealed specific binding of cyclophilin A to the N-terminal domain of C2I . In conclusion , our results suggest an essential role of cyclophilin A for translocation of C2I across endosomal membranes during the uptake of P06681 toxin into mammalian cells . The non-immunosuppressive cyclosporin A analogue SDZ NIM 811 inhibits cyclophilin A incorporation into virions and virus replication in human immunodeficiency virus type 1-infected primary and growth-arrested T cells . SDZ NIM 811 is a cyclosporin A ( DB00091 ) analogue that is completely devoid of immunosuppressive capacity but exhibits potent and selective anti-human immunodeficiency virus type 1 ( HIV-1 ) activity . Binding to cyclophilin A , the intracellular receptor for cyclosporins , is a prerequisite for HIV-1 inhibition by cyclosporins . P62937 was demonstrated to bind to HIV-1 p24gag and this cyclophilin-Gag interaction leads to the incorporation of cyclophilin A into HIV-1 virions . SDZ NIM 811 inhibits this protein interaction , and this is likely to be the molecular basis for its antiviral activity . Here , we show that in activated primary T cells SDZ NIM 811 interferes with two stages of the virus replication cycle : ( i ) translocation of pre-integration complexes into the nucleus and ( ii ) production of infectious virus particles . SDZ NIM 811 not only inhibits translocation of HIV-1 pre-integration complexes in primary T cells , but also in a growth-arrested T cell line . In vivo , most T lymphocytes are quiescent , but serve nevertheless as a major and inducible HIV-1 reservoir in infected individuals . Significant amounts of cyclophilin A were found to be associated with virus particles propagated in primary T cells . SDZ NIM 811 caused a strong reduction in the amount of incorporated cyclophilin A , thereby reducing infectivity . Thus , cyclophilin A seems to be necessary for HIV-1 replication in primary T cells . SERCA2b activity is regulated by cyclophilins in human platelets . OBJECTIVE : The role of cyclophilins ( chaperones that are widely expressed in different cell types , including human platelets ) was explored in sarcoendoplasmic calcium ( Ca(2+) ) adenosine triphosphatase ( SERCA ) activity . METHODS AND RESULTS : Cyclophilin inhibition by cyclosporin A ( DB00091 ) evoked a time- and concentration-dependent reduction of Ca(2+) uptake by SERCA2b . However , other Ca(2+)-adenosine triphosphatases expressed in platelets , such as Q93084 and plasma membrane Ca(2+) adenosine triphophatase , remained unaltered after DB00091 treatment . Cypermethrin , a non- DB00091 -related calcineurin inhibitor , did not alter SERCA2b activity . Furthermore , SERCA2b was affected by other DB00091 analogues , which do not interfere with calcineurin , such as PKF-211-811-NX5 ( NIM811 ) and sanglifehrin A . Inhibition of the immunophilin family members using FK506 ( tacrolimus ) did not alter SERCA2b ability to sequester Ca(2+) into the dense tubular system . Coimmunoprecipitation experiments confirmed that cyclophilin A associates with SERCA2b and stromal interaction molecule-1 in resting platelets . This interaction is attenuated by the physiological agonist thrombin but enhanced by treatment with DB00091 or sanglifehrin A . CONCLUSIONS : P62937 is a regulator of SERCA2b in human platelets . Nitrergic response to cyclophosphamide treatment in blood and bone marrow . Daily intraperitoneal injection of cyclophosphamide ( P15085 ) ( 50 mgkg(-1) of body weight ) for 5 days resulted in reduced levels of marrow and blood cellularity , which was most pronounced in 18 days post-treatment ( pt ) . On day 18 after P15085 treatment the enhancedlevels of nitric oxide ( NO ) precursors and metabolites ( L-arginine , L-citrulline , reactive nitrogen species ( RNS ) ) of marrow and blood cells ( platelet , neutrophil , lymphocyte and monocyte ) resulted from up-regulation of Ca(II)/calmodulin( P62158 )-independent " inducible " NO synthase ( P35228 ) , with a lessercontribution of Ca(II)/ P62158 -dependent " constitutive " P29474 isoforms to systemic NO.Biphasic response to P15085 of marrow nitrergic system , i.e. both P35228 and P29474 showed significantly depressed activities , as well as diminished levels of NO metabolites on day 9 pt , suggested that signals in addition to NO might be involved in P15085 -induced inhibition of hematopoesis , while a gradual increase of neutrophil and platelet NOS activity appeared to be contributed to a P15085 -induced development of granulopenia , thrombocytopenia and hemorrhage . P62937 is an inflammatory mediator that promotes atherosclerosis in apolipoprotein E-deficient mice . P62937 ( CyPA ; encoded by Ppia ) is a ubiquitously expressed protein secreted in response to inflammatory stimuli . CyPA stimulates vascular smooth muscle cell migration and proliferation , endothelial cell adhesion molecule expression , and inflammatory cell chemotaxis . Given these activities , we hypothesized that CyPA would promote atherosclerosis . P02649 -deficient ( Apoe(-/-) ) mice fed a high-cholesterol diet for 16 wk developed more severe atherosclerosis compared with Apoe(-/-)Ppia(-/-) mice . Moreover , CyPA deficiency was associated with decreased low-density lipoprotein uptake , P19320 ( vascular cell adhesion molecule 1 ) expression , apoptosis , and increased P29474 ( endothelial nitric oxide synthase ) expression . To understand the vascular role of CyPA in atherosclerosis development , bone marrow ( BM ) cell transplantation was performed . Atherosclerosis was greater in Apoe(-/-) mice compared with Apoe(-/-)Ppia(-/-) mice after reconstitution with CyPA(+/+) BM cells , indicating that vascular-derived CyPA plays a crucial role in the progression of atherosclerosis . These data define a role for CyPA in atherosclerosis and suggest CyPA as a target for cardiovascular therapies . Insights into the roles of cyclophilin A during influenza virus infection . P62937 ( CypA ) is the main member of the immunophilin superfamily that has peptidyl-prolyl cis-trans isomerase activity . CypA participates in protein folding , cell signaling , inflammation and tumorigenesis . Further , CypA plays critical roles in the replication of several viruses . Upon influenza virus infection , CypA inhibits viral replication by interacting with the M1 protein . In addition , CypA is incorporated into the influenza virus virions . Finally , DB00091 ( DB00091 ) , the main inhibitor of CypA , inhibits influenza virus replication through CypA-dependent and -independent pathways . This review briefly summarizes recent advances in understanding the roles of CypA during influenza virus infection . Cbl-b is a negative regulator of inflammatory cytokines produced by IgE-activated mast cells . c-Cbl and Cbl-b E3 ubiquitin ligases are abundantly expressed in hemopoietic cells where they negatively regulate the activity and levels of many cell surface receptors and associated signaling molecules . By comparing bone marrow-derived mast cells from c-Cbl and Cbl-b-deficient mice it has recently been shown that Cbl-b is the dominant family member for negatively regulating signaling responses from high-affinity IgE receptors . In this study , we suggest that a possible reason for the greater enhancement of IgE receptor signaling in Cbl-b-deficient mice is the relatively higher levels of Cbl-b protein over c-Cbl in mast cells compared with other hemopoietic cells . We also directly compare mast cells from c-Cbl and Cbl-b-deficient mice and find that loss of Cbl-b , but not c-Cbl , increases cell growth , retards receptor internalization , and causes the sustained tyrosine phosphorylation of Syk and its substrates . However , loss of Cbl-b does not enhance the activation of P29323 or Akt , nor does it promote a greater calcium response . Furthermore , loss of Cbl-b or c-Cbl does not increase levels of the Syk or Lyn protein tyrosine kinases . Most notable , however , is the extremely large increase in the production of proinflammatory cytokines P01375 , P05231 , and P13500 by Cbl-b(-/-) mast cells compared with levels produced by c-Cbl(-/-) or wild-type cells . This marked induction , which appears to be restricted to these three cytokines , is dependent on IgE receptor activation and correlates with enhanced O15111 phosphorylation . Thus , Cbl-b functions as a potent negative regulator of cytokines that promote allergic and inflammatory reactions . The influence of costimulation and regulatory P01730 + T cells on intestinal IgA immune responses . It is thought that IgA B-cell differentiation is highly dependent on activated P01730 + T cells . In particular , cell-cell interactions in the Peyer 's patches involving P25942 and/or P33681 / P42081 have been implicated in germinal-center formation and IgA B-cell development . Also soluble factors , such as P05112 , P05113 , P05231 , and TGF beta may be critical for IgA B-cell differentiation in vivo . Here we report on some paradoxical findings with regard to IgA B-cell differentiation and specific mucosal immune responses that we have recently made using gene knockout mice . More specifically , we have investigated to what extent absence of P01730 + T cells , relevant cytokines , or T-cell-B-cell interactions would influence IgA B-cell differentiation in vivo . Using P01730 - or P05112 -gene knockout mice or mice made transgenic for DB01281 , we found that , although specific responses were impaired , total IgA production and IgA B-cell differentiation appeared to proceed normally . However , a poor correlation was found between , on the one hand , GC formation and IgA differentiation and , on the other hand , the ability to respond to T-cell-dependent soluble protein antigens in these mice . Thus , despite the various deficiencies in P01730 + T-cell functions seemingly intact IgA B-cell development was observed . Evidences of monomer , dimer and trimer of recombinant human cyclophilin A . P62937 ( CyPA ) is a cytosolic receptor of immunosuppressive drug cyclosporin A ( DB00091 ) which possesses peptidyl-prodyl cis/trans isomerase ( PPIase ) activity . The recombinant human CyPA ( rhCyPA ) gene has been expressed in E. coli M15 . Purification was performed using salting-out , as well as Sephacryl S-100 and DEAE-Sepharose CL-6B column chromatography . The molecular weight is about 18 kDa , confirmed by SDS-PAGE and mass spectrum . The results of Native-PAGE and immunoblotting showed the existence of three bands , which agreed well with the gel filtration results . The molecular mass of the three bands determined via CTAB gel electrophoresis and SDS-PAGE ( rhCyPA cross-linked with glutaraldehyde ) was 18 kDa , 36 kDa and 54 kDa respectively . Further more , the native rhCyPA and the cross-linked rhCyPA had the similar chromatographic behavior in gel filtration . All of the evidences above suggest that rhCyPA exists in forms of monomer , dimer and trimer . Moreover , we observed that even at low protein concentrations CyPA largely occurs as a dimer in solution , and enzyme kinetic parameters showed that activity of dimer was much higher than monomer or trimer , which probably have some biological significances . Immunophilins in nervous system degeneration and regeneration . Immunophilins are receptors for immunosuppressive drugs like cyclosporin A , FK506 , rapamycin and their non- immunosuppressive analogs , which are collectively referred to as " immunophilin ligands " ( Q53GA4 ) . DB00091 binds to a class of IP called cyclophilins , whereas the receptors for FK506 and rapamycin belong to the family of FK506- binding proteins ( FKBP ) . The latter are designated according to their molecular weight : P62942 , 25 , 52 etc . FKBP levels in the rat brain are up to 50 times higher than in the immune system . P62942 is associated with IP3 and ryanodine receptors present on the endoplasmic reticulum and plays a role in stabilizing calcium release . It has also been proposed to be a modulator of the TGFbeta receptor activity . Crush injury of facial or sciatic nerves in rat leads to markedly increased P62942 levels in the respective nerve nuclei and this increase is related to nerve regeneration . P62937 protects cells from death following expression of mutant Cu/ Zn superoxide dismutase , which is associated with familial amyotrophic lateral sclerosis . Our recent studies show that P62942 and Q02790 are expressed in the human nervous system , especially in the substantia nigra- deep gray matter axis . In neurodegenerative diseases , P62942 levels increase in neurons situated in areas of pathology . This IP colocalizes with synaptophysin and alpha- synuclein , suggesting that it may become a novel marker of pathology . Immunophilins participate in axonal transport , synaptic vesicle assembly and may play a role in neuroprotection against abnormal protein aggregation , suggesting a potential avenue of therapeutic interventions . P62937 is upregulated in small cell lung cancer and activates P27361 /2 signal . P62937 ( CypA ) , a peptidyl-prolyl cis-trans isomerase ( PPIase ) , was originally identified as the intracellular receptor for cyclosporin A ( DB00091 ) . Recently , correlations of CypA with tumor pathogenesis have been studied . Here , we studied the expression of CypA and its receptor CD147 in several kinds of lung cancer cells as well as a normal lung cell and found that in H446 cell , a kind of small cell lung cancer cell , the expression are the highest . The exogeneous CypA protein can substantially stimulate H446 cell growth in dependence on its PPIase activity . We also showed that CypA protein can stimulate P27361 /2 signal in dose and time dependent manners and almost has no effect to p38 and JNK signals . Elucidation of the precise role of CypA in these pathways may lead to new targeted therapies for small cell lung cancer . TGF-β-elicited induction of tissue inhibitor of metalloproteinases ( P01033 ) -3 expression in fibroblasts involves complex interplay between P84022 , p38α , and P27361 /2 . Transforming growth factor-β ( TGF-β ) promotes extracellular matrix deposition by down-regulating the expression of matrix degrading proteinases and upregulating their inhibitors . Tissue inhibitor of metalloproteinases ( P01033 ) -3 is an Q13201 -associated specific inhibitor of matrix degrading metalloproteinases . Here , we have characterized the signaling pathways mediating TGF-β-induced expression of P35625 . Basal and TGF-β-induced P35625 mRNA expression was abolished in Q13485 -deficient mouse embryonic fibroblasts and restoring Q13485 expression rescued the response . Inhibition of Smad signaling by expression of O15105 and dominant negative P84022 completely abolished TGF-β-elicited expression of P35625 in human fibroblasts , whereas overexpression of P84022 enhanced it . Inhibition of extracellular signal-regulated kinase 1/2 ( P27361 /2 ) activation with PD98059 and p38 mitogen-activated protein kinase activity by SB203580 resulted in suppression of TGF-β-induced P35625 expression , indicating that P27361 /2 and p38 MAPK mediate the effect of TGF-β on P35625 expression . Specific activation of p38α and P27361 /2 by constitutively active mutants of MKK3b or Q02750 , respectively , and simultaneous co-expression of P84022 resulted in induction of P35625 expression in the absence of TGF-β indicating that P84022 co-operates with p38 and P27361 /2 in the induction of P35625 expression . These results demonstrate the complex interplay between P84022 , p38α , and P27361 /2 signaling in the regulation of P35625 gene expression in fibroblasts , which may play a role in inflammation , tissue repair , and fibrosis . P62937 as a target of DB00515 chemosensitizers . Platinum-based chemotherapeutics are the mainstay of treatment of a range of tumors achieving high response rates but limited in the course of disease by appearance of drug resistance . Tumor cells respond with reduced uptake and increased intracellular inactivation of the drugs , as well as increased DNA repair and general resistance to chemotherapyinduced cell death . DB00515 is known to induce expression of cyclophilins , a group of proteins that have peptidyl-prolyl cis-trans isomerase ( PPIase ) and molecular chaperone activities , as stress response . P62937 ( CypA ) and other members of this family are inhibited by cyclosporin A ( DB00091 ) which sensitized diverse drug-resistant tumor cell lines in vitro to cisplatin . This effect of DB00091 was attributed to metabolic changes , inhibition of DNA repair , enhancement of apoptosis , altered intracellular signal transduction or increased production of reactive oxygen species ( ROS ) , although no definitive explanation was provided so far . Several clinical trials employing cisplatin/carboplatin in combination with DB00091 yielded unsatisfactory results . Since viral replication was found to be dependent on cyclophilins of the host cells , effective new inhibitors , different from DB00091 or with low or absent immunosuppressive activity , are in development or clinical trials . Sanglifehrins are more potent than DB00091 and proved to increase toxicity of cisplatin against hepatocellular cancer cells in vitro . These novel cyclophilin inhibitors may offer new opportunities to achieve reversal of resistance to platinumbased drugs in refractory patients . Responsive cancer patients may be enriched in clinical trials by an identification of the downstream targets of Cyps responsible for chemoresistance . Marine invertebrates cross phyla comparisons reveal highly conserved immune machinery . Naturally occurring histocompatibility responses , following tissue-to-tissue allogeneic contacts , are common among numerous colonial marine invertebrate taxa , including sponges , cnidarians , bryozoans and ascidians . These responses , often culminating in either tissue fusions or rejections , activate a wide array of innate immune components . By comparing two allorejection EST libraries , developed from alloincompatible challenged colonies of the stony coral Stylophora pistillata and the ascidian Botryllus schlosseri , we revealed a common basis for innate immunity in these two evolutionary distant species . Two prominent genes within this common basis were the immunophilins , P62937 ( CypA ) and FK506-binding protein ( FKBP ) . In situ hybridizations revealed that mRNA expression of the coral and ascidian immunophilins was restricted to specific allorecognition effector cell populations ( nematoblasts and nematocytes in the coral and morula cells in the ascidian ) . The expressions were limited to only some of the effector cells within a population , disclosing disparities in numbers and location between naïve colonies and their immune challenged counterparts . Administration of the immunosuppression drug DB00091 -A during ascidian 's allogeneic assays inhibited both fusion and rejection reactions , probably through the inhibition of ascidian 's immunocytes ( morula cells ) movement and activation . Our results , together with previous published data , depict an immunophilins-based immune mechanism , which is similarly activated in allogeneic responses of distantly related animals from sponges to humans . DB01098 improves endothelial function in db/db mice : role of angiotensin II type 1 receptors and oxidative stress . BACKGROUND AND PURPOSE : P04035 inhibitors , statins , with lipid-reducing properties combat against atherosclerosis and diabetes . The favourable modulation of endothelial function may play a significant role in this effect . The present study aimed to investigate the cellular mechanisms responsible for the therapeutic benefits of rosuvastatin in ameliorating diabetes-associated endothelial dysfunction . EXPERIMENTAL APPROACH : Twelve-week-old db/db diabetic mice were treated with rosuvastatin at 20 mg·kg⁻¹ ·day⁻¹ p.o.for 6 weeks . Isometric force was measured in isolated aortae and renal arteries . Protein expressions including angiotensin II type 1 receptor ( AT₁R ) , Q9NPH5 , O75935 (phox) , p67(phox) , Rac-1 , nitrotyrosine , phospho- P27361 /2 and phospho-p38 were determined by Western blotting , while reactive oxygen species ( ROS ) accumulation in the vascular wall was evaluated by dihydroethidium fluorescence and lucigenin assay . KEY RESULTS : DB01098 treatment of db/db mice reversed the impaired ACh-induced endothelium-dependent dilatations in both renal arteries and aortae and prevented the exaggerated contractions to angiotensin II and phenylephrine in db/db mouse renal arteries and aortae . DB01098 reduced the elevated expressions of AT₁R , O75935 (phox) and p67(phox) , Q9NPH5 , Rac1 , nitrotyrosine and phosphorylation of P27361 /2 and p38 MAPK and inhibited ROS production in aortae from db/db mice . CONCLUSIONS AND IMPLICATIONS : The vasoprotective effects of rosuvastatin are attributed to an increase in NO bioavailability , which is probably achieved by its inhibition of ROS production from the AT₁R-NAD(P)H oxidase cascade . P62937 , the major intracellular receptor for the immunosuppressant cyclosporin A , maps to chromosome 7p11.2-p13 : four pseudogenes map to chromosomes 3 , 10 , 14 , and 18 . P62937 ( CyP-A ) , the major intracellular receptor for the immunosuppressant cyclosporin A ( DB00091 ) , is a member of the immunophilin class of proteins , which all possess peptidyl-prolyl cis-trans isomerase activity and , therefore , are believed to be involved in protein folding and/or intracellular protein transport . The CyP-A protein is encoded by a single gene ; in addition , 15 pseudogenes have been identified . Recently , specific binding of CyP-A to the human immunodeficiency virus type 1 ( HIV-1 ) gag protein has been reported . Interestingly , this interaction can be inhibited by the immunosuppressant DB00091 and also by nonimmunosuppressive , CyP-A-binding DB00091 derivatives , which were also shown to exhibit potent anti-HIV-1 activity . Results thus indicate that CyP-A may have an essential function in HIV-1 replication . Using a panel of somatic rodent-human cell hybrids and PCR technology , we localized the coding cyclophilin A gene ( P62937 ) on chromosome 7 and four pseudogenes ( PPIP2 , PPIP3 , PPIP4 , and PPIP6 ) on chromosomes 14 , 10 , 18 , and 3 , respectively . Using chromosome 7 and chromosome 10 deletion hybrid panels , we were able to localize further the coding gene to the region 7p11.2-p13 , as confirmed by fluorescence in situ hybridization analysis , and one pseudogene ( PPIP3 ) to the region 10q11.2-q23 . This is the first report on the regional mapping of members of the CyP-A gene family . Effects of external calcium on the biotransformation of DB06749 to ginsenoside Rd by Paecilomyces bainier 229-7 . DB01373 is a known signalling molecule in eukaryotic cells and plays a central role in the regulation of many cellular processes . In the following study , we report on the effect of external calcium treatments on the biotransformation of DB06749 to ginsenoside Rd by Paecilomyces bainier 229-7 . We observed that the intracellular calcium content of P. bainier 229-7 mycelia was increased in response to exposure to high external Ca(2+) concentrations . Both ginsenoside Rd biotransformation and β-glucosidase activity were both found to be dependent on the external calcium concentration . At an optimal Ca(2+) concentration of 45 mM , maximal ginsenoside Rd bioconversion rate of 92.44 % was observed and maximal β-glucosidase activity of 0.1778 U was reached in a 72-h biotransformation . The Ca(2+) channel blocker Verapamil blocked the trans-membrane influx of calcium and decreased ginsenoside Rd biotransformatiom . In addition , β-glucosidase activity and ginsenoside Rd content decreased by 36.0 and 29.2 % respectively after a 72-h incubation in the presence of 0.05 mM P62158 ( P62158 ) antagonist DB00850 . These results suggest that both Ca(2+) channels and P62158 are involved in ginsenoside Rd biotransformation via regulation of β-glucosidase activity . This is the first report regarding the effects of calcium signal transduction on biotransformation and enzyme activity in fungi . Vasorelaxant activity of some structurally related triterpenic acids from Phoradendron reichenbachianum ( Viscaceae ) mainly by NO production : ex vivo and in silico studies . The aim of the current study was to investigate the vasorelaxant activity of five structurally-related triterpenic acids namely ursolic ( 1 ) , moronic ( 2 ) , morolic ( 3 ) , betulinic ( 4 ) and 3,4-seco-olean-18-ene-3,28-dioic ( 5 ) acids . The vasorelaxant effect of compounds 1-5 were determined on endothelium-denuded and endothelium-intact rat aortic rings pre-contracted with noradrenaline ( 0.1 μM ) . All compounds showed significant relaxant effect on endothelium-intact vessels in a concentration-dependent manner ( p < 0.05 ) . Ursolic , moronic and betulinic acids were the most potent vasorelaxant agents with 11.7 , 16.11 and 58.46 μM , respectively . Since vasorelaxation was blocked by L-NAME , while indomethacin did not inhibit the effect , endothelium-derived nitric oxide seems to be involved in triterpenic 2 and 3 mode of action . Compounds 1-5 were docked with a crystal structure of P29474 . Triterpenes 1-5 showed calculated affinity with P29474 in the C1 and P06681 binding pockets , near the catalytic site ; Ser248 and Asp480 are the residues that make hydrogen bonds with the triterpene compounds . Induction of G2 arrest and binding to cyclophilin A are independent phenotypes of human immunodeficiency virus type 1 Vpr . P62937 ( CypA ) is a member of a family of cellular proteins that share a peptidyl prolyl cis-trans isomerase ( PPIase ) activity . CypA was previously reported to be required for the biochemical stability and function ( specifically , induction of G2 arrest ) of the human immunodeficiency virus type 1 ( HIV-1 ) protein R ( Vpr ) . In the present study , we examine the role of the Vpr-CypA interaction on Vpr-induced G2 arrest . We find that Vpr coimmunoprecipitates with CypA and that this interaction is disrupted by substitution of proline-35 of Vpr as well as incubation with the CypA inhibitor cyclosporine A ( DB00091 ) . Surprisingly , the presence of CypA or its binding to Vpr is dispensable for the ability of Vpr to induce G2 arrest . Vpr expression in CypA-/- cells leads to induction of G2 arrest in a manner that is indistinguishable from that in CypA+ cells . DB00091 abolished CypA-Vpr binding but had no effect on induction of G2 arrest or Vpr steady-state levels . In view of these results , we propose that the interaction with CypA is independent of the ability of Vpr to induce cell cycle arrest . The interaction between Vpr and CypA is intriguing , and further studies should examine its potential effects on other functions of Vpr . P62937 regulates HIV-1 infectivity , as demonstrated by gene targeting in human T cells . The human immunodeficiency virus type 1 ( HIV-1 ) Gag polyprotein binds most members of the cyclophilin family of peptidyl-prolyl isomerases . Of 15 known human cyclophilins , cyclophilin A ( CypA ) has been the focus of investigation because it was detected in HIV-1 virions . To determine whether CypA promotes HIV-1 replication , we deleted the gene encoding CypA ( P62937 ) in human P01730 (+) T cells by homologous recombination . HIV-1 replication in P62937 (-/-) cells was decreased and not inhibited further by cyclosporin or gag mutations that disrupt Gag 's interaction with cyclophilins , indicating that no other cyclophilin family members promote HIV-1 replication . The defective replication phenotype was specific for wild-type HIV-1 since HIV-2/SIV isolates , as well as HIV-1 bearing a gag mutation that confers cyclosporin resistance , replicated the same in P62937 (+/+) and P62937 (-/-) cells . Stable re-expression of CypA in P62937 (-/-) cells restored HIV-1 replication to an extent that correlated with steady-state levels of CypA . Finally , virions from P62937 (-/-) cells possessed no obvious biochemical abnormalities but were less infectious than virions from wild-type cells . These data formally demonstrate that CypA regulates the infectivity of HIV-1 virions . Host cell species-specific effect of cyclosporine A on simian immunodeficiency virus replication . BACKGROUND : An understanding of host cell factors that affect viral replication contributes to elucidation of the mechanism for determination of viral tropism . P62937 ( CypA ) , a peptidyl-prolyl cis-trans isomerase ( PPIase ) , is a host factor essential for efficient replication of human immunodeficiency virus type 1 ( HIV-1 ) in human cells . However , the role of cyclophilins in simian immunodeficiency virus ( SIV ) replication has not been determined . In the present study , we examined the effect of cyclosporine A ( DB00091 ) , a PPIase inhibitor , on SIV replication . RESULTS : SIV replication in human CEM-SS T cells was not inhibited but rather enhanced by treatment with DB00091 , which inhibited HIV-1 replication . DB00091 treatment of target human cells enhanced an early step of SIV replication . CypA overexpression enhanced the early phase of HIV-1 but not SIV replication , while CypA knock-down resulted in suppression of HIV-1 but not SIV replication in CEM-SS cells , partially explaining different sensitivities of HIV-1 and SIV replication to DB00091 treatment . In contrast , DB00091 treatment inhibited SIV replication in macaque T cells ; DB00091 treatment of either virus producer or target cells resulted in suppression of SIV replication . SIV infection was enhanced by CypA overexpression in macaque target cells . CONCLUSIONS : DB00091 treatment enhanced SIV replication in human T cells but abrogated SIV replication in macaque T cells , implying a host cell species-specific effect of DB00091 on SIV replication . Further analyses indicated a positive effect of CypA on SIV infection into macaque but not into human T cells . These results suggest possible contribution of CypA to the determination of SIV tropism . The H1 histamine receptor regulates allergic lung responses . DB11320 , signaling via the type 1 receptor ( P35367 ) , has been shown to suppress Th2 cytokine production by in vitro cultured T cells . We examined the role of P35367 in allergic inflammation in vivo using a murine asthma model . Allergen-stimulated splenic T cells from sensitized P35367 -/- mice exhibited enhanced Th2 cytokine production . Despite this Th2 bias , allergen-challenged P35367 -/- mice exhibited diminished lung Th2 cytokine mRNA levels , airway inflammation , goblet cell metaplasia , and airway hyperresponsiveness ( P35869 ) . Restoration of pulmonary Th2 cytokines in P35367 -/- mice by intranasal P05112 or P35225 restored inflammatory lung responses and P35869 . Further investigation revealed that histamine acts as a T cell chemotactic factor and defective T cell trafficking was responsible for the absence of lung inflammation . Cultured T cells migrated in response to histamine in vitro , but this was ablated by blockade of P35367 but not P25021 . In vivo , allergen-specific WT but not P35367 -/- P01730 + T cells were recruited to the lungs of naive recipients following inhaled allergen challenge . P35367 -/- T cells failed to confer airway inflammation or P35869 observed after transfer of WT T cells . Our data establish a role for histamine and P35367 in promoting the migration of Th2 cells into sites of allergen exposure . P62937 and P62942 interact with P25490 and alter its transcriptional activity . P25490 is a zinc finger transcription factor with unusual structural and functional features . In a yeast two-hybrid screen , two cellular proteins , cyclophilin A ( CyPA ) and FK506-binding protein 12 ( P62942 ) , interacted with P25490 . These interactions are specific and also occur in mammalian cells . DB00091 and FK506 efficiently disrupt the P25490 -CyPA and P25490 - P62942 interactions . Overexpression of human CyPA and P62942 have different effects on P25490 -regulated transcription with these effects being promoter-dependent . These results suggest that immunophilins may be mediators in the functional role of P25490 . 1-(2,6-Dibenzyloxybenzoyl)-3-(9H-fluoren-9-yl)-urea : a novel cyclophilin A allosteric activator . P62937 ( CypA ) plays an important role in many physiology processes and its overexpression has been involved in many diseases including immune disease , viral infection , neuro-degenerative disease , and cancer . However , the actual role of CypA in the diseases is still far from clear , and a complete understanding of CypA is necessary in order to direct more specific and effective therapeutic strategies . Based on the screening of our in-house library through the isomer-specific proteolysis method , we find a CypA activator ( 1-(2,6-Dibenzyloxybenzoyl)-3-(9H-fluoren-9-yl)-urea ) , compound 1a , which can increase CypA 's PPIase activity and give allosteric behavior . The binding affinity of compound 1a to CypA has been confirmed by Fortebio 's Octet Q13123 system and the increased phosphorylation of P29323 in H446 cells is observed by treatment with both compound 1a and DB00091 . In order to further evaluate the binding mode between the activator and CypA , the allosteric binding site and allosteric mechanism of CypA are investigated by molecular dynamics ( MD ) simulations in combination with mutagenesis experiments . The results show that the allosteric binding site of CypA is 7Å away from its catalytic site and is composed of Cys52 , His70 , His54 , Lys151 , Thr152 and Lys155 . Compound 1a binds to the allosteric site of CypA , stabilizing the active conformation of catalytic residues , and finally promotes the catalytic efficiency of CypA . We believe our finding of the CypA allosteric activator will be used as an effective chemical tool for further studies of CypA mechanisms in diseases . Secreted cyclophilin A , a peptidylprolyl cis-trans isomerase , mediates matrix assembly of hensin , a protein implicated in epithelial differentiation . Q9UGM3 is a rabbit ortholog of Q9UGM3 , a multifunctional , multidomain protein implicated in the regulation of epithelial differentiation , innate immunity , and tumorigenesis . Q9UGM3 in the extracellular matrix ( Q13201 ) induced morphological changes characteristic of terminal differentiation in a clonal cell line ( clone C ) of rabbit kidney intercalated cells . Although hensin is secreted in monomeric and various oligomeric forms , only the polymerized Q13201 form is able to induce these phenotypic changes . Here we report that hensin secretion and matrix assembly were inhibited by the peptidylprolyl cis-trans isomerase ( PPIase ) inhibitors cyclosporin A ( DB00091 ) and a derivative of cyclosporin A with modifications in the d- DB00133 side chain ( Cs9 ) but not by the calcineurin pathway inhibitor FK506 . PPIase inhibition led to failure of hensin polymerization in the medium and Q13201 , plus the loss of apical cytoskeleton , apical microvilli , and the columnar epithelial shape of clone C cells . P62937 was produced and secreted into the media to a much greater extent than cyclophilins B and C . Our results also identified the direct DB00091 -sensitive interaction of cyclophilin A with hensin , suggesting that cyclophilin A is the PPIase that mediates the polymerization and matrix assembly of hensin . These results are significant because this is the first time a direct role of peptidylprolyl cis-trans isomerase activity has been implicated in the process of epithelial differentiation . Anti-inflammatory effect of transduced PEP-1-cyclophilin A in Raw264.7 cells and 12-O-tetradecanoylphorbol-13-acetate-induced mice . AIMS : P62937 ( CypA ) is an immunophilin that acts as a receptor for the immunosuppressant drug cyclosporine A ( DB00091 ) . CypA has emerged as a potential drug target for several inflammatory diseases , although the details of its mechanism are unclear . We examined the protective effects of CypA on inflammation in Raw 264.7 cells and animal models . MAIN METHODS : A human CypA gene was fused with a protein transduction domain , PEP-1 peptide , to construct a cell permeable PEP-1-CypA protein . The protein expression level of cyclooxygenase-2 ( P35354 ) and cytokines was detected by Western blot , ELISA and mRNA level of P35354 and cytokines were measured by RT-PCR . The nuclear factor-kappa B ( NF-kB ) and mitogen-activated protein kinase ( MAPK ) activation were analyzed by Western blot and electrophoretic mobility shift assay . Skin inflammation was detected with immunohistochemistry . KEY FINDINGS : Transduced PEP-1-CypA protein markedly inhibited lipopolysaccharide- and 12-O-tetradecanoyl phorbol-13-acetate-induced expression levels of P35354 as well as pro-inflammatory cytokine levels in vitro and in vivo . Furthermore , transduced PEP-1-CypA protein resulted in a significant reduction in the activation of NF-kB and MAPK . SIGNIFICANCE : The results indicate that PEP-1-CypA inhibits inflammatory response cytokines and enzymes by blocking NF-kB and MAPK activation upon stimulation of inflammation in vitro and in vivo . PEP-1-CypA protein may potentially be used as a therapeutic agent against skin diseases-related inflammation .