目的 探讨3’-羟基葛根素改善胰岛素抵抗的作用及其机制。方法 采用MTT法检测3’-羟基葛根素对3T3-L1前脂肪细胞增殖的影响；油红O染色法检测其对3T3-L1前脂肪细胞分化的影响。以地塞米松诱导分化成熟的脂肪细胞，建立胰岛素抵抗模型，分别采用葡萄糖氧化酶法和比色法检测细胞培养上清液中葡萄糖消耗量和游离脂肪酸（FFA）生成量；实时荧光定量PCR法分析脂肪细胞中过氧化物酶体增殖物激活受体γ（peroxysome proliferator-activated receptor gamma，PPARγ）和蛋白酪氨酸磷酸酶1B（protein tyrosine phosphatase 1B，PTP1B）的基因表达。采用嵌合蛋白基因试验检测3’-羟基葛根素的PPARγ配体结合活性和比色法检测其对PTP1B酶活性的影响。结果 与溶媒对照组相比，1～10 μmol/L 3’-羟基葛根素显著促进3T3-L1前脂肪细胞增殖及细胞分化（P<0.05、0.01）。与模型组相比，无论在基础状态还是胰岛素刺激状态，3’-羟基葛根素均能显著增加胰岛素抵抗脂肪细胞葡萄糖利用率、减少FFA的产生（P<0.05、0.01）；同时显著上调胰岛素抵抗脂肪细胞PPARγ基因的表达，但对PTP1B基因表达无明显影响（P>0.05）。与溶媒对照组相比，3’-羟基葛根素在0.1、10.0 μmol/L时能对PPARγ产生激活作用（P<0.05、0.01），但对PTP1B酶活性没有明显抑制作用（P>0.05）。结论 3’-羟基葛根素能促进胰岛素抵抗脂肪细胞葡萄糖利用、抑制FFA产生，从而改善胰岛素抵抗，其机制可能与上调PPARγ基因表达有关。

Objective To investigate the effects of 3'-hydroxy puerarin on improving insulin resistance in 3T3-L1 adipocytes and their mechanisms. Methods The proliferation of 3T3-L1 preadipocytes was tested by MTT assay and the differentiation by oil red O staining. The insulin resistance model was induced by dexamethasone. Cellular glucose consumption was determined by GOD-POD assay and the concentration of FFA by colorimetric methods. The expression of PPARγ and PTP1B genes in insulin resistant adipocytes was analyzed by qPCR. The PPARγ-transactivation activity of 3'-hydroxy puerarin was examined by using a hybrid reporter gene assay and the activity of PTP1B by colorimetric methods. Results Compared with the medium control group, 3'-hydroxy puerarin significantly activated PPARγ at 0.1 and 10 μmol/L (P < 0.05, 0.01), but showed no effect on PTP1B (P > 0.05); increased the proliferation and differentiation of 3T3-L1 preadipocytes at 1-10 μmol/L (P < 0.05, 0.01). Compared with model group, 3'-hydroxy puerarin enhanced cellular glucose consumption in insulin resistant adipocytes both in basic and insulin stimulation states, decreased the production of FFA, and up-regulated the expression of PPARγ gene (P < 0.01), but showed no effect on the expression of PPARγ gene (P > 0.05). Conclusion 3'-Hydroxy puerarin can improve the insulin resistance via up-regulating the expression of PPARγ.

广东省高等学校科技创新重点项目（cxzd1111）