Effect And Mechanism Of Dietary Pattern Of Lard And Vegetable Oil On Reducing NAFLD Risk

In recent years,the high prevalence of nonalcoholic fatty liver disease(NAFLD)in the world has brought great challenges to human health.The global prevalence of NAFLD was up 24% in 2017 and is closely related to the dietary pattern,especially dietary oils/fats.NAFLD prevalence in China was around 15%,but showed a rapid growth trend.In Chinese traditional dietary oil habit,lard is usually mixed with vegetable oils.Our previous study found that mixture of lard and soybean oil had an anti-obesity effect.The present study aimed to explore the effects of Chinese traditional dietary oil habits(mixed lard with sunflower oil and soybean oil separately)on NAFLD development based on a mouse model and investigate its mechanism.1)Explored different oils/fats impact on the development of NAFLD under the condition of 30% fat energy to simulate Chinese residents’ dietary oil/fat habits.Fifty(50)male C57BL/6J of about six(6)weeks age were divided into five(5)groups and,respectively,given with natural-ingredient diet with lard,sunflower oil(SFO),soybean oil(SBO),lard mixed with sunflower oil(L-SFO),lard mixed with soybean oil(L-SBO).After 12 weeks,results showed that(1)compared with lard and SFO groups,the final body weight of mice in L-SFO group decreased by 7% and 7.6%,respectively;compared with lard and SBO groups,the L-SBO group decreased by 8.8% and 16.6%,respectively;the white adipose tissue weight,body fat rate,and cross-section area of adipose tissue of mice in L-SBO group also decreased significantly,while just showed decreasing trends in L-SFO group.(2)Compared to the lard group,serum TG and FFA of L-SFO and L-SBO groups decreased significantly,while showed a decreasing trend compared with SFO and SBO groups.(3)Compared to lard and SFO groups,the ALT activity,liver TG content,and liver oil-red stain area of L-SFO present decreased trends,while compared with the SBO group,the L-SBO group decreased significantly.(4)Compared with SFO and SBO groups,the HSL protein expression showed an up-regulated trend in L-SFO group,while a significant up-regulation in the L-SBO group;p-AMPK/AMPK value in L-SFO and L-SBO groups were significantly higher than lard,SFO,and SBO groups;compared with lard group,the serum leptin,insulin content,and HOMA-IR value decreased in L-SFO and L-SBO groups.These results illustrated that mixed oil diets have a function of decreasing body fat,serum lipids,and liver lipid content,alleviating liver steatosis via the activated AMPK pathway and reducing insulin resistance,while the mixture of lard and soybean oil is superior to the mixture of lard and sunflower oil.2)Explored different oils/fats impact on the development of NAFLD under the condition of 10% and 15.5% fat energy to simulate Chinese residents’ dietary habits.Ninety(90)male C57BL/6J of 6 weeks age were divided into 6 groups and supplied with a purified diet with10% fat energy lard(L1),10% fat energy soybean oil(S1),10% fat energy mixture of lard and soybean oil(LS1),15.5% fat energy lard(L2),15.5% fat energy soybean oil(S2),and15.5% fat energy mixture of lard and soybean oil(LS2)respectively,for 16 weeks.The results showed that:(1)Under the two levels of fat energy,compared with lard and soybean oil,mixed oil decreased body weight,body weight gain,white adipose tissue weight,and body fat rate.(2)Compared with lard,mixed oil decreased serum LDL-C,HDL-C,and TC contents,and HDL-C/LDL-C value significantly,and compared with lard,and soybean oil,mixed oil decreased serum TG and FFA content.(3)Compared with soybean oil,mixed oil significantly reduced ALT and AST capability;and compared with lard,and soybean oil,mixed oil significantly reduced liver TG content,while liver FFA showed a decreasing trend and showed significant difference with lard.(4)Compared with lard and soybean oil,mixed oil lowered expression of FABP2 in the liver;also,compared with lard,mixed oil decreased the gene expression of Fas,mt-cytb,TRAF2,JUN,and IL-1 in the liver;and compared with soybean oil,mixed oil up-regulated gene expression of AMPKα2,and HSL in the liver.The results indicate that the mixture of lard and soybean oil diet has a function of reducing the fatty acid absorption and transport by down-regulating the expression of FABP2,regulating the expression of related genes in the AMPK signal pathway to promote lipolysis,and reducing liver lipid deposition,thus reducing liver steatosis.At the same time,mixed oil reduces the expression of inflammation-related genes that benefit the alleviation of steatohepatitis,so as to reduce the risk of NAFLD.In conclusion,based on natural-ingredient diets and purified diets,mice were used to simulate the dietary habits of Chinese residents under the energy of 10%～30%.Chinese traditional dietary oil habit(mixed lard and vegetable oils)has a function of reducing the risk of NAFLD,and the mixture of lard and soybean oil diet was better than the mixture of lard and sunflower oil diet.The underlying mechanisms observed are reducing absorption and transport of fatty acids by down-regulated expression of FABP2,promoting lipolysis via regulated genes in the AMPK pathway,and reducing gene expression related inflammation caused by FFA overloaded,thus ultimately decreasing the risk of NAFLD.