Improvement effect of baicalin on dexamethasone-induced insulin resistance of rat adipocyte

Abstract

Abstract: AIM: To study the improvement effect of baicalin on rat adipocyte insulin resistance and its mechanism.METHODS: Using enzyme-digesting method, proadipocyte cells from the rat inguinal adipose tissues which were cut under sterile conditions were cultured.The proadipocytes were induced to differentiate into mature adipocyte .Then adipocyte insulin resistance was induced by dexamethasone . Two groups of dexamethasone -induced insulin resistance adipocytes were given the following treatments for 48 hours: baicalin treated group(baicalin 20 μg/mL 48 h) ,rosiglitazone treated group(rosiglitazone 10 μmol/L 48 h) . In addition, vehicle-treated adipocytes and normal controls were used in the experiment. Glucose in every group adipocyte supernatant were detected by glucose oxidase. Enzyme-linked immunosorbent assay (ELISA) was employed to monitor the levels of supernatant adiponectin and resistin. The expression of PPARγ were detected by immumohisto-chemical technique.RESULTS: The levels of glucose consumption in baicalin treated group and rosiglitazone treated group were significantly increased compared with insulin resistance group (P＜0.01). The levels of adiponectin and the expression of PPARγ were also increased in baicalin treated group and rosiglitazone treated group compared with insulin resistance group while the levels of resistin were decreased(P＜0.05,P＜0.01).CONCLUSION: Baicalin can increase glucose consumption in insulin resistance adipocyte and improve insulin resistance. The effect may be due to the increase of adiponectin induced by the upregulation of the expression of the PPARγand decrease of resistin.

Key words: Baicalin, Insulin resistance, Adiponectin, Resistin, PPARγ

CLC Number:

R965.2

SHEN Hong-yan , WU Xiao-dong. Improvement effect of baicalin on dexamethasone-induced insulin resistance of rat adipocyte[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2011, 16(3): 263-269.

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