Articles : Effects of Food Restriction on Rat Adipose Tissue Lipoprotein Lipase Activity and Lipogenesis |
|
Abstract |
The current study was undertaken the effects of various degrees of food restriction on rat adipose tissue lipoprotein lipase (LPL) activity and lipogenesis. Thirty male Sprague-Dawely rats weighing 290 g were divided nto three groups according to body weight and raised for four weeks. The full-fed group was fed ad-libitum and the food restricted groups were fed either mildly restricted (20% food restricted group) or severly restricted diet (40% food restricted group). Lipogenesis was determined by the amount of glucose converted to a total lipid. Serum lipoprotein pattern, triglyceride coneentration and their correlation with LPL activity were also investigated. As expected, body weight gain and epididymal adipose tissue weight were higher in the full-fed group (p<0.05). The serum total cholesterol and LDL cholesterol concentrations were not significantly affected by food restriction. However, HDL-cholesterol concentration and HDL-C/T-C ratio were signiticantly higher in the food restricted groups than they were in the full-fed group (p<0.05). The serum triglyceride concentration of full-fed rats tended to be higher than that of the 40% food restricted rats (p<0.05). There was no difference in lipogenesis between food restricted groups, but lipogenesis was significantly higher in the 40% food restricted group than in the full-fed group (p<0.05). The LPL activity of adipose tissue was significantly lower in the 40% restricted group than that in the full-fed group (p<0.05), but that of the 20% restricted group was similar to the full-fed group. LPL activity in adipose tissue had a positive correlation with triglyceride concentration, which had a negative correlation with HDL-cholesterol concentration. These results suggest that food restriction leads to the decreased activity of LPL, thereby potentially reducing lipid storage. |
Key Words:
food restriction, lipoprotein pattern, lipoprotein lipase, lipogenesis |
|