荔枝核拮抗2型糖尿病大鼠胰岛素抵抗作用的药理学机制

目的:研究荔枝核水提取物(water extract from Semen Litchi,以下简称荔枝核)改善2型糖尿病大鼠(T2DM)胰岛素抵抗(IR)的药理学机制.方法:采用T2DR-IR模型,观察荔枝核对T2DM-IR大鼠空腹血清血糖(FSG)、总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)、血清尿素氮(BUN)、肌酐(Cr)、总蛋白(TP)、白蛋白(A)、丙二醛(MDA)、瘦素(1eptin)、肿瘤坏死因子-α(TNF-α)、胰岛素(Fins)含量及胰岛素敏感指数(ISI),以及丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、超氧化物歧化酶(SOD)活性等指标的影响.结果:荔枝核能显著降低T2DM-IR大鼠FSG、TC、TG、FFA、leptin和TNF-α含量及高胰岛素血症(P＜0.05～0.01),显著提高ISI(P＜0.01),增强胰岛素敏感性;加强SOD活性和降低MDA的含量(P＜0.01),增强抗氧化能力;降低ALT、AST活性和BUN、Cr含量,提高TP、A含量(P＜0.05～0.01),改善肝肾功能.结论:荔枝核能调整T2DM-IR大鼠Lept和TNF-α含量及高胰岛素血症,拮抗IR,改善胰岛素敏感性,调节糖脂代谢紊乱,增强抗氧化作用,并具有改善肝肾功能作用.

Pharmacological Mechanism of Semen Litchi on Antagonizing Insulin Resistance in Rats with Type 2 Diabetes

OBJECTIVE: To investigate the pharmacological mechanism of Semen Litchi water extract (SL) on enhancing insulin sensitivity in type 2 diabetic rats (T2DR) with insulin resistance (IR). METHODS: The effects of SL were observed on serum contents of fasting glucose (FSG), blood urea nitrogen (BUN), creatine (Cr), total proteins (TP), albumin (A), malondialdehyde (MDA), total cholesterols (TC), triacylglycerol (TG), free fatty acid (FFA), leptin, tumor necrosis factor-alpha (TNF-alpha), fasting insulin (Fins) and index of insulin sensitivity (ISI), and activities of superoxide dismutase (SOD), alanine aminotransferase (ALT), aspartate aminotransferase (AST) in T2DR-IR. RESULTS: In T2DR-IR, SL could lower concentrations of FSG, TC, TG, FFA, leptin, TNF-alpha and Fins (P < 0.05-0.01), increase ISI (P < 0.01), reform the hyperinsulinemia and insulin sensitivity, decrease the levels of BUN, Cr and the activities of ALT, AST, increase concentration of TP, A (P < 0.05-0.01), recover the hepatic and nephric functions, increase the activity of SOD and decrease content of MDA (P < 0.01). CONCLUSION: SL could reduce the levels of TNF-alpha, hyper-leptinemia and hyperinsulinemia, antagonize insulin resistance, fortify insulin sensitivity, readjust lipodystrophy and maladjustment of glycometabolism, enhance antioxidation,and improve functions of liver and kidney in T2DR-IR.