{'fraction_non_alphanumeric': 0.032667876588021776, 'fraction_numerical': 0.024500907441016333, 'mean_word_length': 5.644578313253012, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Comparison of Inhibitory Effects of Nine Flavonoids on Prostaglandin E2 Production and COX-2 Expression in LPS-Stimulated RAW264.7 Macrophages

Prostaglandin E2 (PGE2) has a crucial role in inflammation and is synthesized by cyclooxygenase-2 (COX-2), of which the expression is induced in inflammatory site by inflammatory stimuli like lipopolysaccharide (LPS). In the present study, nine flavonoids were tested for their effects on prostaglandin E2 production and cyclooxygenase-2 expression in LPS-stimulated RAW 264.7 macrophages. All the nine compounds, including apigenin, lute Olin, scutellarein, quercetin, myricetin, isoquercitrin, genistein, hyperoside, rutin effectively inhibited the LPS-induced PGE2 production but only isoquercitrin showed the significant inhibitory effect on the COX-2 expression. It was found that isoquercitrin exhibited a concentration-dependent inhibition of PGE2 production and COX-2 expression with the estimated IC50 values of 25 μM and 65 μM, respectively. The results introduce isoquercitrin as a good compound capable of down regulating the expression of COX-2.