The Effects Of N-6/n-3 Ratio Of Fat Acids On Antioxidation Capability, Blood Fat And Bone Metabolism Of Mice Fed With High Fat Diet

Different ratios of the n-6 polyunsaturated fatty acid (PUFA) to n-3 PUFA and different content of Alpha-lipoic acid ( LA ,0.05%, 0.1%) in high fat diet affecting the capability of the antioxidation and blood fat metabolism was investigated; We also studied the change of the gene related to lipid metabolism and the lipid peroxidation in liver of mice. During the second stage, the effect of 3 ratios of mixed oil (5:1, 10:1, 15:1) supplemented with 0.05,01% LA on bone characters of the high fat diet mice was investigated.C57 male mice were fed for 6 weeks with a high fat diet (21.48% crude fat) in 2 different ratios of mixed oil (ratio1 5:1, ratio2 10:1) and 2 different content of LA (0.05%, 0.1%, w/w) .The results show that high fat intake decreases anti-oxidative ability of mice. However, mixed oil increase the level of SOD, decrease the MDA both in the serum and the liver, thereby increased the T-AOC of the mouse, improved the fat metabolism in the liver, decreased the content of the TC, TG, LDL-C, decrease AI and increase the content of the HDL-C. The ratio 10:1 is better than the ratio 5:1.When LA was added, the negative effect of the lipid peroxidation was significantly relieved, the capability of the anti-oxidation is increased. The improvement of the 0.05% LA group is significant (P<0.05) , the 0.1% LA group is better than the 0.05% group but not significant.It was found that enzymes related toβ-lipid oxidation were significantly down-regulated, the PPARs related to the metabolism of carbohydrate and the lipid significantly were down-regulated, when we add 0.1%LA, both of them reduced to control level analysed from gene chip. It showed that the LA could effect the enzymes related to the lipid metabolism, to control the level of the blood lipid of the body.In the second stage, we fed the KM male mice for 6 weeks with 3 different ratios of mixed oil (ratio 1 5:1, ratio 1 10:1, ratio 1 15:1) content 0.05% LA in high fat diet (21.48% crude fat). The different ratios of mixed oil affect different indexes, and didn't show the semblable trend. The result of MMP-9 is ratio2 < ratio 1< ratio3; PICP is ratio1 < ratio 2 < ratio3; the result of BGP is ratio1 < ratio 2 < ratio3; the resule of BALP are close.When we add 0.05% LA, the indexes related to the osteoblast changed in a positive way. The index MMP-9 which related to the osteocalst (OC) decreased significantly. It shows that LA has a strong effect in inhibiting the expression of the OC, prevent the bone resorption. But the mechanism needs further researched .