Department of Seafood Science, National Kaohsiung University of Science and Technology, Nanzi 81157, Taiwan.
Department of Food Science, National Taiwan Ocean University, Keelung 20224, Taiwan.
Molecules. 2021 Jul 12;26(14):4232. doi: 10.3390/molecules26144232.
Although the hypoglycemic potential of brewer's yeast extract has been reported, there is limited information pertaining to the hypoglycemic ingredients of extract and their mechanisms of action available. This study aimed to investigate the in vivo and in vitro hypoglycemic effect of extract and to elucidate its molecular mechanisms. extract was mainly composed of proteins followed by carbohydrates. In diabetic rats, oral administration of extract significantly reduced the levels of plasma glucose and enhanced the activity of hepatic glucose-6-phosphatase dehydrogenase. Treatment with extract increased the localization of type 4 glucose transporter (GLUT4), PTP, and insulin receptor at 3T3-L1 cell membranes and raised the levels of P38 MAPK, PI3K, and AKT in the cytosol. In agreement with these results, pretreatment of 3T3-L1 cells with inhibitors of PTP, PI3K, Akt/PKB, and p38 MAPK inhibited glucose uptake induced by application of extract. Most importantly, a 54 kDa protein with hypoglycemic activity was identified and suggested as the major ingredient contributing to the hypoglycemic activity of extract. In summary, these results clearly confirm the hypoglycemic activity of extract and provide critical insights into the underlying molecular mechanisms.
尽管已经报道了啤酒酵母提取物的降血糖潜力，但有关提取物的降血糖成分及其作用机制的信息有限。本研究旨在探讨提取物的体内和体外降血糖作用，并阐明其分子机制。提取物主要由蛋白质组成，其次是碳水化合物。在糖尿病大鼠中，口服给予提取物可显著降低血浆葡萄糖水平，并增强肝葡萄糖-6-磷酸酶脱氢酶的活性。提取物处理增加了 3T3-L1 细胞膜上的 4 型葡萄糖转运蛋白 (GLUT4)、PTP 和胰岛素受体的定位，并提高了细胞质中 P38 MAPK、PI3K 和 AKT 的水平。与这些结果一致，用 PTP、PI3K、Akt/PKB 和 p38 MAPK 的抑制剂预处理 3T3-L1 细胞可抑制提取物诱导的葡萄糖摄取。最重要的是，鉴定出一种具有降血糖活性的 54 kDa 蛋白，并认为其是提取物降血糖活性的主要成分。总之，这些结果清楚地证实了提取物的降血糖活性，并为其提供了关键的分子机制见解。
