Effects of Endogenous n-3PUFA on Body Weight, Autophagy and Inflammation in Mice

Author(s): Xin Fang, Chao Song, YinLin Ge, JinYu Zhang

The fat-1 transgenic mice were used as models, to investigate the effects of n-3PUFAs on body weight, the expression of inflammation and autophagy in mice, and to explore its mechanism. The mice were divided into two groups: fat-1 transgenic mice and wild-type mice. The body weight and body length were measured and the index of body weight/body length was calculated regularly every week for 8 weeks. Cardiac blood was collected for determination of TG, CT, HDL-C, LDL-C and BG. Frozen sections of liver were stained by Oil Red O to observe the lipid droplets. The expression of autophagy proteins P62, LC3 and ATG7 in the hypothalamus were detected by western blot, and the relative quantitative analysis was performed. Real-time quantitative PCR was used to quantify the mRNA expression of TNF-α, IL-6, IL-1β, IFN-γ, MCP-1, TLR-4 and adiponectin in epididymal adipose tissue. The body weight/body length of fat-1 transgenic mice was significantly lower than that of wild-type mice(P<0.05), the levels of TG, CT, HDL-C, LDL-C and BG in the serum of fat-1 transgenic mice were significantly lower than those in wild-type mice(P<0.05). Lipid droplets in the liver of fat-1 transgenic mice were significantly less. The expression of P62 in fat-1 transgenic mice was significantly down-regulated (P <0.05), while the expression of ATG7 was significantly increased (P <0.05), and the ratio of LC3 Ⅱ / Ⅰ was significantly increased(P<0.05). The results of real-time quantitative PCR showed that the mRNA relative expression of TNF-α, IL-6, IL-1β, IFN-γ, MCP-1 and TLR-4 in epididymal fat tissue of fat-1 transgenic mice was significantly decreased, and the expression of adiponectin was increased (P < 0.05). n-3PUFAs reduce the body weight to prevent obesity may by up-regulation of hypothalamic autophagy, and down-regulation of inflammation in peripheral fat.

Hypothalamus, n-3 PUFAs, Autophagy, Inflammation

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