Jokura Hiroko, Watanabe Isamu, Umeda Mika, Hase Tadashi, Shimotoyodome Akira
Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi, 321-3497, Japan.
Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi, 321-3497, Japan.
Nutr Res. 2015 Oct;35(10):873-881. doi: 10.1016/j.nutres.2015.07.005. Epub 2015 Aug 4.
Epidemiological studies indicate that habitual coffee consumption lowers the risk of diabetes and cardiovascular diseases. Postprandial hyperglycemia is a direct and independent risk factor for cardiovascular diseases. We previously demonstrated that coffee polyphenol ingestion increased secretion of Glucagon-like peptide 1 (GLP-1), which has been shown to exhibit anti-diabetic and cardiovascular effects. We hypothesized coffee polyphenol consumption may improve postprandial hyperglycemia and vascular endothelial function by increasing GLP-1 release and/or reducing oxidative stress. To examine this hypothesis, we conducted a randomized, acute, crossover, intervention study in healthy male adults, measuring blood parameters and flow-mediated dilation (FMD) after ingestion of a meal with or without coffee polyphenol extract (CPE). Nineteen subjects consumed a test meal with either a placebo- or CPE-containing beverage. Blood biomarkers and FMD were measured at fasting and up to 180 minutes postprandially. The CPE beverage led to a significantly lower peak postprandial increase in blood glucose and diacron-reactive oxygen metabolite, and significantly higher postprandial FMD than the placebo beverage. Postprandial blood GLP-1 increase tended to be higher after ingestion of the CPE beverage, compared with placebo. Subclass analysis revealed that the CPE beverage significantly improved postprandial blood GLP-1 response and reduced blood glucose increase in the subjects with a lower insulinogenic index. Correlation analysis showed postprandial FMD was negatively associated with blood glucose increase after ingestion of the CPE beverage. In conclusion, these results suggest that coffee polyphenol consumption improves postprandial hyperglycemia and vascular endothelial function, which is associated with increased GLP-1 secretion and decreased oxidative stress in healthy humans.
流行病学研究表明，习惯性饮用咖啡可降低患糖尿病和心血管疾病的风险。餐后高血糖是心血管疾病的直接和独立危险因素。我们之前证明，摄入咖啡多酚可增加胰高血糖素样肽1（GLP-1）的分泌，该物质已被证明具有抗糖尿病和心血管作用。我们推测，食用咖啡多酚可能通过增加GLP-1释放和/或减少氧化应激来改善餐后高血糖和血管内皮功能。为了验证这一假设，我们对健康成年男性进行了一项随机、急性、交叉干预研究，测量在摄入含或不含咖啡多酚提取物（CPE）的餐后血液参数和血流介导的血管舒张（FMD）。19名受试者食用了含有安慰剂或CPE饮料的试验餐。在空腹和餐后长达180分钟时测量血液生物标志物和FMD。与安慰剂饮料相比，CPE饮料导致餐后血糖和二亚铬反应性氧代谢物的峰值增加显著降低，餐后FMD显著升高。与安慰剂相比，摄入CPE饮料后餐后血液GLP-1的增加趋势更高。亚组分析显示，CPE饮料显著改善了胰岛素生成指数较低的受试者的餐后血液GLP-1反应，并降低了血糖升高。相关性分析表明，摄入CPE饮料后，餐后FMD与血糖升高呈负相关。总之，这些结果表明，食用咖啡多酚可改善餐后高血糖和血管内皮功能，这与健康人体内GLP-1分泌增加和氧化应激降低有关。
