Objective: To study the effects of dietary different ratios of high-fat n - 3/ n - 6 polyunsaturated fatty acids (PUFAs) on insulin sensitivity and pro-inflammatory cytokines expression in serum of rats.
Methods: 40 young male SD rats (n = 10) after adaptive feeding 7d were randomly divided into 4 groups, fed by common diet, high fat diet, high fat with n - 3/n - 6 1 : 1 PUFAs diet, and high fat with n - 3/n - 6 1 : 4 PUFAs diet. The animals were weighted weekly and sacrificed at 16 weeks, then blood lipids, serum insulin sensitivity and pro-inflammatory cytokines (IL-6, TNF-alpha and hs-CRP) were determined.
Results: Compared with normal control group, three high fat groups result in a significant increase of body weight gain. Insulin sensitivity of high fat 1 : 1 group had no significant difference with normal control, but is significantly higher than high-fat and high-fat 1 : 4 group (P < 0.05). Compared with high fat group, pro-inflammatory cytokines expression of high fat 1 : 1 group decreased significantly (P < 0.05).
Conclusion: High dietary polyunsaturated fatty acids appears associated with a trend towards obesity risk, however, increase of the proportion of n - 3 PUFAs dietary composition effectively decreased the expression of pro-inflammatory cytokines, then, improved insulin sensitivity and prevented insulin resistance.