Effects of different formulations of high-fat diet on establishment of a non-alcoholic fatty liver model in rats / 中国临床药理学与治疗学

ABSTRACT

AIM:To improve the success rate of experimental modeling of non-alcoholic fatty liver(NAFLD)in rats by high-fat diet through comparing three different formulations of high-fat diets in con-structing non-alcoholic fatty liver rats model,so as to provide a reliable animal model for the study of non-alcoholic fatty liver disease.METHODS:SPF-grade male SD rats were divided into four groups randomly:control group,high-fat diet group1(HFD1),high-fat diet group2(HFD2),high-fat diet group3(HFD3).Each group was given the corre-sponding feed for 8 weeks while modeling.The da-ta on general observation,body weight changes,and ingestion of the rats were recorded during the modeling period.After 8 weeks'feeding,liver ultra-sound,CT and MRI examination were performed for the rats of each group to check the status.Blood and liver samples were collected.Changes in liver function(ALT,AST),blood lipids(TC,TG,HDL-C,LDL-C),and inflammatory indexes(IL-1β,IL-6,TNF-α)were detected.The morphology of the liv-ers was observed with the naked eyes,and the liv-er index and Lee's index were calculated at the end of 8 weeks.The effects of different high-fat diets on the establishment of NAFLD model in SD rats were comprehensively evaluated by comparing the difference of above indexes among the groups.RE-SULTS:Compared with the control group,rats in the HFD1,HFD2 and HFD3 groups showed poor mental deterioration,decreased activity,severe hair loss,decreased food intake,increased body weights,and significantly increased liver index and Lee's in-dex,along with increased liver volume,blunt edge,steatosis and lipid deposition,and the trend was even more pronounced in the HFD3 group.Com-pared with the control group,the serum levels of ALT,AST,TC,TG,LDL-C,IL-1β,IL-6 and TNF-α were significantly increased,while the contents of HDL-C was significantly decreased in the HFD1,HFD2 and HFD3 group,especially in the HFD3 group.Com-pared with the control group,the B ultrasonogra-phy showed an enlarged liver with enhanced paren-chymal echo and pipe unsharpness,CT showed that the liver and spleen CT ratio decreased obvi-ously,and the MRI images showed obvious differ-ence of liver signal intensity between in/out of phase image in the HFD1,HFD2 and HFD3 group,and the most significant imaging changes was ob-served in the HFD3 group.CONCLUSION:The above three kinds of high-fat diets can establish NAFLD model in SD rats after 8 weeks'feeding,the models induced by HFD3 was better than those in-duced by the other two groups.NAFLD lesion is rel-atively serious and expected to last longer in HFD3 group,which are more suitable for investigating the underlying mechanisms of non-alcoholic fatty liver disease and development of lipid-lowering drugs.