目的探讨不同糖耐量个体游离脂肪酸(FFA)、脂联素(APN)与胰岛β细胞功能的关系。方法选取35例新诊断的2型糖尿病患者(DM组),30例糖耐量降低者(IGT组),36例正常对照(NGT组),行静脉葡萄糖耐量试验(IVGTT),ELISA法测定空腹APN,比色法测定空腹FFA及糖负荷后120min FFA(FFA120)。计算0~10min胰岛素曲线下面积(AUC)、急性胰岛素反应0-10(AIR0-10)、稳态模型胰岛素抵抗指数(HOMA-IR)及稳态模型胰岛素分泌指数(HOMA-B),并探讨FFA与空腹血糖(FPG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、AUC、AIR0-10、APN、HOMA-B及HOMA-IR的关系。结果DM组、IGT组的APN、AUC、AIR0-10显著低于NGT组(P〈0.05),且DM组显著低于IGT组(P〈0.05)。DM组、IGT组空腹FFA明显高于NGT组(P〈0.05)。FFA与AUC、AIR0-10、HOMA-B、APN、HDL-C呈负相关,与FFA120、TG、FPG呈正相关;APN与FFA、FFA120、TG、LDL-C呈负相关。多元逐步回归分析显示,空腹FFA是AIR0-10的独立影响因素,而FFA的独立影响因素为APN、TG。结论2型糖尿病患者FFA水平明显升高,降低FFA水平将有助于改善β细胞第一时相分泌功能。提高APN水平可能降低FFA,降低脂毒性。
Objective To study the relationship between adiponectin (APN), free fatty acids and pancreatic β-cell function in individuals with different glucose tolerance. Methods Thirty five patients with newly diagnosed type 2 diabetes mellitus (DM group), 30 patients with impaired glucose tolerance (IGT group), 36 individuals with normal glucose tolerance (NGT group, as control) were enrolled and intravenous glucose tolerance test (IVGTT) was conducted. Fasting APN was assayed by ELISA, and levels of fasting free fatty acids (FFA) and 120 minutes after glucose loading FFA (FFA120) were measured by colorimetry. 0-10 minutes insulin the area under the curve (AUC), acute insulin response (AIR0-10), HOMA-IR and HOMA-B were calculated to explore the relationship between free fatty acids and the FPG, HDL-C, LDL-C, TG, AUC, AIR0-10, APN, HOMA-B and HOMA-IR. Results APN, AUC and AIR0-10 were significantly lower in DM group and IGT group than in NGT group (P0.05), and APN, AUC and AIR0-10 were significantly reduced in DM group than in IGT group (P0.05). Fasting FFA was significantly higher in DM group and IGT group than that in NGT group (P0.05). FFA was negatively correlated with AUC, AIR0-10, HOMA-B, APN and HDL-C, and positively correlated with FFA120, TG, FBG and LDL-C. APN was negative correlated with FFA, FFA120, TG and LDL-C. Stepwise multiple regression analysis showed that fasting FFA was the independent factor of AIR0-10, while FFA was the independent factor of APN and TG. Conclusions FFA levels are significantly elevated in patients with type 2 DM. Lowering FFA levels will help to improve the β-cell function of the first phase. As one of the independent factors of FFA, elevation of APN levels may reduce the FFA and improve lipotoxicity.