Shen Yan, Fukushima Misato, Ito Yoshimasa, Muraki Etsuko, Hosono Takashi, Seki Taiichiro, Ariga Toyohiko
Laboratory of Nutrition and Physiology, Department of Chemistry and Life Science, Nihon University College of Bioresource Sciences, Nihon University Graduate School of Bioresource Sciences, Kanagawa, Japan.
Biosci Biotechnol Biochem. 2010;74(12):2418-25. doi: 10.1271/bbb.100453. Epub 2010 Dec 7.
It has long been believed that an intake of cinnamon (Cinnamomum zeylanicum) alleviates diabetic pathological conditions. However, it is still controversial whether the beneficial effect is insulin-dependent or insulin-mimetic. This study was aimed at determining the insulin-independent effect of cinnamon. Streptozotocin-induced diabetic rats were divided into four groups and orally administered with an aqueous cinnamon extract (CE) for 22 d. The diabetic rats that had taken CE at a dose of more than 30 mg/kg/d were rescued from their hyperglycemia and nephropathy, and these rats were found to have upregulation of uncoupling protein-1 (UCP-1) and glucose transporter 4 (GLUT4) in their brown adipose tissues as well as in their muscles. This was verified by using 3T3-L1 adipocytes in which CE upregulates GLUT4 translocation and increases the glucose uptake. CE exhibited its anti-diabetic effect independently from insulin by at least two mechanisms: i) upregulation of mitochondrial UCP-1, and ii) enhanced translocation of GLUT4 in the muscle and adipose tissues.
长期以来，人们一直认为摄入肉桂（锡兰肉桂）可缓解糖尿病病理状况。然而，这种有益作用是依赖胰岛素还是模拟胰岛素仍存在争议。本研究旨在确定肉桂的非胰岛素依赖性作用。将链脲佐菌素诱导的糖尿病大鼠分为四组，口服肉桂水提取物（CE）22天。服用剂量超过30mg/kg/d CE的糖尿病大鼠血糖和肾病得到缓解，并且发现这些大鼠棕色脂肪组织和肌肉中的解偶联蛋白-1（UCP-1）和葡萄糖转运蛋白4（GLUT4）上调。这通过使用3T3-L1脂肪细胞得到验证，其中CE上调GLUT4易位并增加葡萄糖摄取。CE至少通过两种机制独立于胰岛素发挥其抗糖尿病作用：i）线粒体UCP-1上调，ii）肌肉和脂肪组织中GLUT4易位增强。
