Zhang Shiqi, Ma Xiaohan, Zhang Lei, Sun Hui, Liu Xiong
College of Food Science, Southwest University , Tiansheng Road 2, Chongqing 400715, People's Republic of China.
College of Life Science, Chongqing Normal University , Chongqing 401331, People's Republic of China.
J Agric Food Chem. 2017 Mar 22;65(11):2323-2330. doi: 10.1021/acs.jafc.7b00132. Epub 2017 Mar 2.
Chili peppers exhibit antiobesity, anticancer, antidiabetic, and pain- and itch-relieving effects on animals and humans; these effects are due to capsaicin, which is the main pungent and biologically active component of pepper. Capsiate, a nonpungent capsaicin analogue, is similar to capsaicin in terms of structure and biological activity. In this study, we investigated whether capsaicin and capsiate exhibit the same hypoglycemic effects on rats with type 1 diabetes (T1D). Experimental rats were categorized into four groups: control, model, capsaicin, and capsiate groups. The two treatment groups were treated orally with 6 mg/kg bw capsaicin and capsiate daily for 28 days. Treatment with capsaicin and capsiate increased body weight, increased glycogen content, and inhibited intestinal absorption of sugar in T1D rats. Particularly, insulin levels were increased from 14.9 ± 0.76 mIU/L (model group) to 22.4 ± 1.39 mIU/L (capsaicin group), but the capsiate group (16.7 ± 0.79 mIU/L) was increased by only 12.2%. Analysis of the related genes suggested that the transient receptor potential vanilloid 1 (TRPV1) receptor was activated by capsaicin. Liver X receptor and pancreatic duodenum homeobox 1 controlled the glycometabolism balance by regulating the expression levels of glucose kinase, glucose transport protein 2 (GLUT2), phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase, leading to reduced blood glucose levels in T1D rats. Meanwhile, the hypoglycemic effect was enhanced by the down-regulated expression of sodium glucose cotransporter 1, GLUT2, and GLUT5 in the intestine. The results showed that the spicy characteristics of capsaicin might be the root of its ability to decrease blood glucose.
辣椒对动物和人类具有抗肥胖、抗癌、抗糖尿病以及止痛和止痒作用;这些作用归因于辣椒素,它是辣椒主要的辛辣且具有生物活性的成分。辣椒素酯,一种无辣味的辣椒素类似物,在结构和生物活性方面与辣椒素相似。在本研究中,我们调查了辣椒素和辣椒素酯对1型糖尿病(T1D)大鼠是否具有相同的降血糖作用。实验大鼠分为四组:对照组、模型组、辣椒素组和辣椒素酯组。两个治疗组每天口服6mg/kg体重的辣椒素和辣椒素酯,持续28天。辣椒素和辣椒素酯治疗增加了T1D大鼠的体重,增加了糖原含量,并抑制了肠道对糖的吸收。特别是,胰岛素水平从14.9±0.76mIU/L(模型组)增加到22.4±1.39mIU/L(辣椒素组),但辣椒素酯组(16.7±0.79mIU/L)仅增加了12.2%。对相关基因的分析表明,辣椒素激活了瞬时受体电位香草酸亚型1(TRPV1)受体。肝脏X受体和胰腺十二指肠同源盒1通过调节葡萄糖激酶、葡萄糖转运蛋白2(GLUT2)、磷酸烯醇式丙酮酸羧激酶和葡萄糖-6-磷酸酶的表达水平来控制糖代谢平衡,从而降低T1D大鼠的血糖水平。同时,肠道中钠葡萄糖协同转运蛋白1、GLUT2和GLUT5表达下调增强了降血糖作用。结果表明,辣椒素的辣味特征可能是其降低血糖能力的根源。