The Effects of Capsaicin on Decrease of Weight and Consumption of Energy in Obesity Rats by High-fat Diet

Abstract

To clarify the effects of capsaicin on obese rats, 6-week-old and 44-week-old male Wistar rats were each separated into 4 groups. One group was given a commercial flour diet for 8 weeks (control diet group). The second group was given the commercial flour diet for 4 weeks, followed by the same diet supplemented with 0.021% capsaicin (control+capsaicin diet group). The third group was given the commercial flour diet supplemented with 16.3% lard for 4 weeks, followed by the commercial diet (high-fat diet group). The fourth group was given the commercial diet supplemented with 16.3% lard for 4 weeks, followed by the commercial diet supplemented with 0.021% capsaicin (high-fat+capsaicin diet group). Body weight, plasma triglycerides, glucose, total cholesterol, and free fatty acid levels, and the brain epinephrine level, were measured at the end of the diet period. The results were as follows: 1) The body weight of the rats fed capsaicin decreased, the decrease being greater in the high fat group than in the control group. 2) The decrease of body weight in rats fed capsaicin was greater in older than in younger rats. 3) In the rats fed capsaicin, the plasma triglyceride concentration was decreased and the glucose concentration was increased; the brain epinephrine level was also increased. 4) The body weight of older rats fed capsaicin was more decreased than that of younger rats fed capsaicin. The effects of capsaicin on triglyceride and total cholesterol levels were significantly more marked in younger than in older rats.