短期高脂饮食对中国汉族男性2型糖尿病患者糖脂代谢的影响

目的研究短期高脂饮食对中国汉族男性2型糖尿病(T2DM)患者糖脂代谢的影响。方法9例单纯饮食控制或仅用二甲双胍治疗的男性2型糖尿病患者先后分别服用高碳水化合物餐(HCD)和高脂肪餐(HFD)3 d,进食第3天多点抽血,测定血浆葡萄糖及胰岛素变化,并于第4天行静脉葡萄糖耐量试验(IVGTT)。结果进食HFD患者的非酯化脂肪酸(NEFA)24 h曲线下面积(AUC)显著高于进食HCD患者(P<0.001),且其24 h血浆葡萄糖AUC显著低于HCD患者(P<0.05);而24 h胰岛素AUC两种饮食患者差异无显著性;进食HFD患者72 h后空腹血浆葡萄糖接近显著意义地升高(P=0.056),低密度脂蛋白胆固醇水平升高(P<0.05)。IVGTT进食HFD患者葡萄糖刺激的胰岛素快速反应接近显著意义地升高(P=0.06),血浆空腹和早餐段餐后胰升血糖素亦显著升高。结论短期进食HFD使NEFA暴露水平显著升高,葡萄糖暴露水平显著降低,空腹血浆葡萄糖升高但不伴胰岛素水平的显著变化可能是肝糖输出增加、胰岛素抵抗形成的早期表现,提示胰升血糖素在胰岛素抵抗的形成中起了重要作用,而显著的β细胞功能失调(脂毒性)可能需要更长时间。

Influence of short-term high-fat diet on glucose and lipid metabolism in male Han Chinese with type 2 diabetes mellitus

OBJECTIVE: To investigate the influence of short-term high-fat diet (HFD) on glucose and lipid metabolism in male Han Chinese with type 2 diabetes mellitus (T2DM). METHODS: Middle-aged T2DM men supported with solely diet or diet and metformin were enrolled into the study. The design was an unblinded crossover design. Each of the subjects randomly received one from two types of isocalorie (8786.4 kJ/d) standard diet for three consecutive days on two occasions, with a 6-week wash-out period in between. The component ratios of fat, carbohydrate, and protein were 50%, 35%, and 15% vs. 25%, 60%, and 15% in patients administered with HFD or high carbohydrate diet (HCD). The 24-hour blood samples during the third day were collected. On the morning of the forth day an intravenous glucose tolerance test (IVGTT) was conducted with 25g of glucose. RESULTS: According to the determination results of 24-hour profile samples, HFD resulted in a markedly increased circulating level of non-esterified fatty acid (NEFA) as compared to HCD (P < 0.001). Nearly significant higher (P = 0.056) FPG was observed 72 hours after the administration of HFD. Circulating insulin levels were comparable between the two diets. A significantly higher HDL-C was also observed after HFD administration (P < 0.05). As assessed by the IVGTT, acute insulin response of glucose (AIRg) tended to increase after the HFD administration (P = 0.06). Fasting plasma glucagons (GLG) level and AUC(Glucagon) during breakfast period (8:00-12:00) were significantly higher after HFD administration than that of after HCD administration. CONCLUSIONS: Short-term HFD induced the increase of NEFA with lower glucose exposure to the patietns. Fasting plasma glucose increased at the fourth day without remarkable changes of insulin levels which may be due to the increase of hepatic glucose output after HFD administration. The short-term HFD in our study induced early stage of insulin resistance. GLG seemed to play a role in this procedure. beta-cell dysfunction may need a longer high NEFA exposure.