[Study on the differential expression of lipid metabolism-related genes in young LDLR knockout mice liver].

Objective To clarify the differential expression of the genes related to the lipid metabolism in the early stage of atherosclerosis in the young LDLR-/- mice of different ages.Methods A RT-PCR assay was used to analyse the gene expression patterns in the livers of LDLR-/- mice and wild type (WT) mice from 14 to 90 days.The characteristics of early lipid deposition in intima were evaluated using biochemical and pathological techniques.Results In LDLR-/- mice,when compared to WT mice,the mRNA level of the apolipoprotein A Ⅳ(apoA Ⅳ),fatty acid translocase(Fat/CD36)and carnitine palmitoyl transferase Ⅰ(CPT Ⅰ) changed prominently at the age of 14-days(P＜0.05).At 30 days,the mRNA level of apolipoprotein A Ⅰ(apoA Ⅰ) was up regulated,but apolipoprotein F(apoF),CD36 and CPT Ⅰ were down regulated(P＜0.05).At 60 days,the mRNA levels of apoA Ⅰ,CPT Ⅰ and liver Ⅹ receptor α(LXRα) were up regulated,but apoAⅣ was down regulated(P＜0.05).At 90 days,the level of the apoA Ⅰ was higher,but the expression of the apoA Ⅳ,apoF and acyl-coenzymeA oxidase 1 (ACOX1) were down regulated (P＜0.05),whereas the expression of apolipoprotein A Ⅴ(apoA Ⅴ),apolipoprotein E (apoE),peroxidase proliferator-activated receptor α(PPARα) and angiopoietin-like protein 3(angptl 3) had no significant changes(P＞0.05).The serum levels of TC(P＜0.05),TG(P＜0.05)and LDLC(P＜0.05) in LDLR-/- mice were significantly higher than those in wild type mice with the same age.Conclusions The mRNA levels of the apoA Ⅰ,apoA Ⅳ,apoF,FAT/CD36,CPT Ⅰ,ACOX1 and LXRα of the LDLR-/- mice were significantly changed compared to the WT mice.The genes may be of some relevance to the complicated lipid metabolism network,and have effect in the early stage of atherogenesis. Key words: Receptors,LDL; Lipid metabolism; Liver;  Atherosclerosis;  Animal experimentation