梓醇与小檗碱及其配伍对胰岛素抵抗3T3-L1脂肪细胞的影响

Effect of catalpol,berberine,and their combination on insulin resistant 3T3-L1 adipocytes

目的观察梓醇与小檗碱及其配伍对地塞米松诱导的胰岛素抵抗3T3-L1脂肪细胞葡萄糖消耗、转运及这一过程中过氧化物体增殖物激活受体(PPAR-γ)mRNA表达的影响。方法采用地塞米松诱导胰岛素抵抗细胞模型,分别给予罗格列酮、小檗碱、梓醇、梓醇+小檗碱进行干预,以葡萄糖氧化酶法检测培养液中葡萄糖消耗量,以2-脱氧-[3H]-D-葡萄糖摄入法观察葡萄糖的转运率,以RT-PCR检测PPAR-γmRNA的表达。结果含或不含10nmol/L胰岛素的条件下,梓醇、小檗碱及其配伍组胰岛素抵抗脂肪细胞的葡萄糖消耗量和转运率较模型组明显改善(P<0.05、0.01),配伍组效应优于梓醇、小檗碱单药组(P<0.05、0.01);且小檗碱组及配伍组PPAR-γmR-NA的表达降低(P<0.05、0.01)。结论梓醇、小檗碱均能增加葡萄糖消耗和转运,改善胰岛素抵抗,其作用不依赖胰岛素的存在,且小檗碱及两药配伍还能下调脂肪细胞PPAR-γmRNA的表达水平,提示梓醇、小檗碱改善胰岛素抵抗的作用机制可能与罗格列酮不同。

Objective To study the effect of catalpol, berberine, and their combination on glucose consumption and transportation of insulin resistant 3T3-L1 adipocytes induced by Dexamethasone, and expression of cell peroxisome proliferator-activated receptor-γ （PPAR-γ） mRNA. Methods Adipocyte insulin resistance （IR） model was induced with Dexamethasone and under the intervention of rosiglitazone, berberine, catalpol, and combination of catalpol and berberine. Glucose consumption of cells incubated with corresponding medicine was assayed with glucose oxidase method, glucose transporting rate was detected with measuring the uptake of [^3H] 2-DG, and PPAR-γ mRNA expression was tested with RTPCR. Results With or without 10 nmol/L insulin, glucose consumption and transportation in catalpol, berberine, and the combination groups were significantly improved in comparision with the model （P〈 0.05 and 0. 01）, the effect of the combination group was better than that of the single drug groups （P〈 0.05 and 0. 01）. Adipocyte PPAR-γ mRNA expression was down-regulated in berberine and the combination groups （P〈 0.05 and 0. 01）. Conclusion Both catalpol and berberine can increase the glucose consumption and transportation and improve IR. The actions are independent of insulin. Berberine can also down-regulate the expression of PPAR-γ mRNA, which indicates the machnism of their improving IR may differ from that of rosiglitazone.