[Effects of dietary different ratios of n-3 to n-6 polyunsaturated fatty acids influence lipid metabolism and appetite of rats].
OBJECTIVE
To study the effects of dietary different ratios of n-3 to n-6 polyunsaturated fatty acids on food intake of SD rats and potential mechanisms.


METHODS
According to their serum total cholesterol level, male rats were randomly divided into 6 groups, and were fed common feed diet, high fat diet, high fat with n-3/n-6 1:1 PUFA diet, high fat with n-3/n-6 1:5 PUFA diet, common feed with n-3/n-6 1:1 PUFA diet, and common feed with n-3/n-6 1:5 PUFA diet, respectively. Weights were measured about every 6 days, and food intake were measured everyday. At 0, 15, 30 and 45 days, triglycerides (TG) and total cholesterol (TC) in the plasma were measured using kits. After 45 days, the rats were sacrificed. RT-PCR was used for measuring the expression of neuropepide Y (NPY) and AMP-activated protein kinase-alpha2 (AMPK-alpha2) mRNA in the hypothalamus.


RESULTS
Four diets with any ratio of n-3/n-6 PUFA resulted in significant restraint of body weight gain, TC and TG level in the plasma, NPY and AMPK-alpha2 mRNA level in the hypothalamus compared to high fat diets (P < 0.05). These situations in two groups with common diet and one group with high diet added 1:1 PUFA are more significant than the high fat diet group.


CONCLUSIONS
These results indicate that dietary PUFA improved lipid metabolism which may be related with appetite control through AMPK path.
Jia
Manxue
M
Department of Nutrition and Food Hygiene, the Fourth Military Medical University, Xi'an 710032, China. jmx1224@hotmail.com
Xue
Nan
N
Cao
Zipeng
Z
Liu
Hanqiang
H
D000818:Animals; D001066:Appetite / Q000187:drug effects*; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage / Q000494:pharmacology; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000494:pharmacology; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage* / Q000494:pharmacology; D050356:Lipid Metabolism / Q000187:drug effects*; D008297:Male; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D004042:Dietary Fats, Unsaturated; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6