不同比例低碳高脂饮食对糖代谢的影响

Effects of Low-carbohydrate High-fat Diet on Glucose Metabolism

目的探讨不同比例低碳高脂饮食对C57小鼠及2型糖尿病患者糖代谢的影响。方法C57小鼠40只,随机分为4组,给予普通饮食及不同碳水化合物比例的3种高脂饲料。每周测量体质量及摄食量,并检测随机血糖及胰岛素。腹腔注射葡萄糖耐量试验、胰岛素耐量试验及丙酮酸耐量试验评估小鼠代谢水平。另取C57小鼠8只,同时给予普通饮食及60%高脂饮食,观察摄食情况。8例2型糖尿病患者,记录低碳饮食1个月前后的饮食结构变化、体质量及血糖水平。结果相较于普通饮食小鼠,3种高脂饮食小鼠能量摄入显著增加(P=0.000)。24周时4组小鼠体质量比较差异有统计学意义(P=0.000)。高脂饮食小鼠出现明显的空腹血糖升高、胰岛素抵抗及肝脏糖异生增加。同时给予普通饮食及高脂饮食时,小鼠优先选择高脂饮食。2型糖尿病患者在低碳饮食1个月后,碳水化合物比例显著减少(P=0.000),脂肪比例增加(P=0.003),空腹及餐后2h血糖显著下降(P值分别为0.013、0.002)。结论随着饮食中碳水化合物比例下降,小鼠能量摄入增多,体质量增长加快,并出现糖代谢的异常,与人群低碳饮食后的表现相反。

Objective To observe the effects of low-carbohydrate high-fat diet on glucose metabolism of mice T2DM patients.Methods Forty mice were randomly divided into four groups with chow diet and three different carbohydrate proportion high-fat diets.Body weight and food intake were measured weekly.To assess metabolism of the mice,concentrations of blood glucose and insulin were detected as well as introperitoneal glucose tolerance test,insulin tolerance test and pyruvate tolerance test were performed.Furthermore,food intake of eight mice was recorded after exposure to chow diet and high-fat diet simultaneously.Eight T2DM patients were selected.Diet structure,body weight,fasting and 2-hour postprandial blood glucose were measured.Results The energy intake of high-fat diet groups were significantly higher than chow diet group(P=0.000).At 24th week,body weight among four groups had a significant difference(P=0.000).High-fat diet groups showed higher fasting blood glucose,insulin resistance and enhanced gluconeogenesis.With exposure to chow diet and high-fat diet simultaneously,the mice took more high fat diet.After one month low-carbohydrate diet,T2DM patients showed lower portion of carbohydrate(P=0.000)and higher portion of fat(P=0.003).Fasting and 2-hour postprandial blood glucose significantly decreased(P=0.013,P=0.002).Conclusion As the proportion of carbohydrates in the diet decreased,the mice showed increased energy intake,accelerated weight gain,and abnormal glucose metabolism,which is opposite to patients undergoing low-carbohydrate diet.