Whistler Center for Carbohydrate Research, Department of Food Science, Purdue University, West Lafayette, IN, United States.
USDA, Agricultural Research Service, Children's Nutrition Research Center and Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States.
Nutrition. 2020 Oct;78:110857. doi: 10.1016/j.nut.2020.110857. Epub 2020 May 15.
Maltase-glucoamylase (Mgam) and sucrase-isomaltase (Si) are mucosal α-glucosidases required for the digestion of starch to glucose. We hypothesized that a dietary approach to reduce Mgam and Si activities can reduce glucose generation and absorption, and improve glucose control.
Rice starch was entrapped in alginate microspheres to moderate in vitro digestion properties. Three groups of 8-wk old mice (n = 8) were conditioned for 7 d with low C-starch-based materials differing in digestion rates (fast, slow, and slower), and then given a digestible C-labeled cornstarch test feeding to determine its digestion to glucose.
Conditioning of the small intestine with the slowly digestible starches for 7 d reduced jejunal α-glucosidase and sucrase activities, as well as glucose absorption for the slowly digestible starch slower group (P < 0.01). A correlative relationship was found between glucose absorption from a cornstarch test feeding given at d 7 and jejunal α-glucosidase and sucrase activities (R = 0.64; 0.67). However, total prandial glucose levels during the 2-h feeding period did not differ.
Decreased glucogenesis from a digestible starch feeding was found in mice conditioned on slowly digestible starch diets, suggesting that a dietary approach incorporating slowly digestible starches may change α-glucosidase activities to moderate glucose absorption rate.
麦芽糖酶-葡糖苷酶（Mgam）和蔗糖酶-异麦芽糖酶（Si）是消化淀粉为葡萄糖所必需的黏膜 α-葡糖苷酶。我们假设通过饮食来降低 Mgam 和 Si 的活性可以减少葡萄糖的生成和吸收，从而改善葡萄糖控制。
将大米淀粉包埋在海藻酸钠微球中，以调节其体外消化特性。将 3 组 8 周龄的小鼠（n = 8）用不同消化速度（快、慢和更慢）的低 C-淀粉基材料进行 7 天的预处理，然后给予可消化的 C 标记玉米淀粉测试喂养，以确定其消化为葡萄糖的情况。
用慢消化淀粉对小肠进行 7 天的预处理，降低了空肠 α-葡糖苷酶和蔗糖酶的活性，以及慢消化淀粉更慢组的葡萄糖吸收（P < 0.01）。在第 7 天进行的玉米淀粉测试喂养中，发现葡萄糖吸收与空肠 α-葡糖苷酶和蔗糖酶活性之间存在相关性（R = 0.64；0.67）。然而，在 2 小时喂养期间的总餐后血糖水平没有差异。
在接受慢消化淀粉饮食预处理的小鼠中，发现可消化淀粉喂养的糖生成减少，这表明通过饮食来纳入慢消化淀粉可能会改变 α-葡糖苷酶活性，从而调节葡萄糖吸收速率。
