Luo Xin-Xin, Zhu Shui-Lan, Li Bing-Tao, Shi Xiu-Ming, Tu Jun
Jiangxi Province Key Laboratory of Traditional Chinese Medicine Etiopathogenisis, Research Center for Differentiation and Development of Traditional Chinese Medicine Basic Theory, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China.
Zhongguo Zhong Yao Za Zhi. 2017 Dec;42(23):4641-4648. doi: 10.19540/j.cnki.cjcmm.20170928.003.
To investigate the effects of Gegen Qinlian decoction(GQD) in improving adipocytic insulin resistance(IR) and explore its related molecular mechanism. Diabetic rats models were induced by high glucose and high-fat diet with a small dose of streptozotocin, and after GQD treatment for 3 months, blood biochemical indexes such as fasting blood-glucose(FBG), insulin, glycosylated serum protein(GSP) and HOMA-IRI were detected and assessed. After the total RNA was extracted from the adipose tissue of diabetic SD rats, PPARγ, ADPN, GLUT4, GLUT2, ACACA and ACACB mRNA expression levels were separately detected by qPCR. Then, stable IR-3T3-L1 adipocyte model was built with 1 μmol•L⁻¹ dexamethasone. After the cell viability was detected by CCK-8 assay, 5%, 10% and 15% GQD-containing serum(GQD-CS) were respectively used to treat IR-3T-L1 adipocytes for 24 h. The contents of glucose, nonesterified fatty acid(NEFA) and adiponectin in cell culture supernatants were separately detected whereas the intracellular triglyceride(TG) contents of IR-3T3-L1 adipocytes were also measured. The ADPN, PPARγ and GLUT4 mRNA and protein expression levels were respectively detected by qPCR and Western blot in IR-3T3-L1 adipocytes. Results showed that GQD significantly decreased fasting blood glucose, insulin and GSP(P<0.01), and down-regulated HOMA-IRI(P<0.05) after the high-fat diet/streptozotocin-induced diabetic SD rats were treated for three months, with a good hypoglycemic effect. Moreover, PPARγ, ADPN, GLUT4, GLUT2, ACACA and ACACB mRNA expression levels were significantly elevated in the adipose tissue of GQD-treated diabetic SD rats. The 5%, 10% and 15% GQD-CS significantly increased glucose consumption of IR-3T3-L1 adipocytes at 24 h treatment(P<0.01), significantly decreased the intracellular TG content (P<0.01), and down-regulated NEFA to a certain extent but not significantly. Moreover, GQD-CS significantly up-regulated GLUT4 and ADPN expression. The results indicated that GQD could activate PPARγ to ameliorate adipocytic insulin resistance in the diabetic SD rats and IR-3T3-L1 adipocytes.
探讨葛根芩连汤（GQD）改善脂肪细胞胰岛素抵抗（IR）的作用及其相关分子机制。采用高糖高脂饮食联合小剂量链脲佐菌素诱导糖尿病大鼠模型，GQD治疗3个月后，检测并评估空腹血糖（FBG）、胰岛素、糖化血清蛋白（GSP）及胰岛素抵抗指数（HOMA-IRI）等血液生化指标。提取糖尿病SD大鼠脂肪组织总RNA后，采用qPCR分别检测过氧化物酶体增殖物激活受体γ（PPARγ）、脂联素（ADPN）、葡萄糖转运蛋白4（GLUT4）、葡萄糖转运蛋白2（GLUT2）、乙酰辅酶A羧化酶α（ACACA）和乙酰辅酶A羧化酶β（ACACB）mRNA表达水平。然后，用1 μmol•L⁻¹地塞米松建立稳定的IR-3T3-L1脂肪细胞模型。通过CCK-8法检测细胞活力后，分别用含5%、10%和15% GQD的血清（GQD-CS）处理IR-3T-L1脂肪细胞24 h。分别检测细胞培养上清液中葡萄糖、非酯化脂肪酸（NEFA）和脂联素的含量，同时测定IR-3T3-L1脂肪细胞内甘油三酯（TG）含量。采用qPCR和Western blot分别检测IR-3T3-L1脂肪细胞中ADPN、PPARγ和GLUT4 mRNA及蛋白表达水平。结果显示，高脂饮食/链脲佐菌素诱导的糖尿病SD大鼠经GQD治疗3个月后，空腹血糖、胰岛素和GSP显著降低（P<0.01），HOMA-IRI下调（P<0.05），降糖效果良好。此外，GQD治疗的糖尿病SD大鼠脂肪组织中PPARγ、ADPN、GLUT4、GLUT2、ACACA和ACACB mRNA表达水平显著升高。含5%、10%和15% GQD的血清在处理24 h时显著增加IR-3T3-L1脂肪细胞的葡萄糖消耗（P<0.01），显著降低细胞内TG含量（P<0.01），并在一定程度上下调NEFA但差异不显著。此外，GQD-CS显著上调GLUT4和ADPN表达。结果表明，GQD可激活PPARγ改善糖尿病SD大鼠和IR-3T3-L1脂肪细胞的脂肪细胞胰岛素抵抗。
