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[Effects of linear alkylbenzenesulfonate on oxidative stress and collagen fiber in skin tissue of mice].

BACKGROUND
To observe the effect of linear alkylbenzenesulfonate (LAS) on oxidative stress and collagen fiber in skin tissue of mice and to explore the correlation between oxidative stress and collagen metabolism. 


METHODS
Forty healthy Kunming mice (male) were randomly divided into 4 groups: a control group, a low-, middle- and high-dose group of LAS (LD, MD and HD groups), treated with LAS at 150, 300 and 600 mg/L respectively (n=10 per group). The skin on the back of mice was smeared with distilled water or different dosage of LAS for 60 days. The measured indexes included general condition of mice, HE and Masson staining of skin, the content of hydroxyproline (Hyp) in skin tissue, the activity of super oxidase dismutase (SOD) and the content of malondialdehyde (MDA) in skin tissue and serum, and the activity of lactate dehydrogenase (LDH) in serum. 


RESULTS
Compared with the control group, the changes of diet, daily activities and mental state of mice with different dose of LAS were not obvious during the experiment, but the body weight of mice in the experimental groups reduced obviously after 4 weeks of experiment (P<0.01), and their skin tissue was thinner, some of epidermis of skin contained areas with cellular necrosis and abscission. Superficial layer of dermis was infiltrated by inflammatory cells. The collagen fibers were looser and dimmer. At the same time, the content of MDA and the activity of LDH increased remarkably (P<0.01), while the activity of SOD and the content of Hyp decreased obviously (P<0.01). 


CONCLUSIONS
LAS can induce oxidative stress in the skin tissue of mice, which can destroy the integrity of skin structure and collagen fiber and reduce the content of collagen fiber. The oxidative damage might be the primary cause for disorders of collagen fiber. .