Effect of miR-19a on lipid catabolism in hepatocyte LO2 / 中国病理生理杂志

ABSTRACT

[ ABSTRACT] AIM: To observe the effect of microRNA-19a ( miR-19a) on the lipid catabolism of hepatocyte LO2, and to explore the potential mechanism.METHODS: miR-19a was over-expressed or silenced by transfection of miR-19a mimics or miR-19a inhibitor into LO2 cells, then the mRNA level of miR-19a was detected by real-time PCR.The potential target of miR-19a was found by the method of bioinformatics through internet website.The effect of miR-19a on the 3’ UTR of peroxisome proliferator-activated receptorα(PPARα) was measured by dual luciferase reporter assay, and the protein level of PPARαand its 2 major downstream rate-limiting enzymes involved in lipid catabolism, acyl-coenzyme a dehydrogenase (ACADM) and carnitine palmitoyltransferase 1A ( CPT1A), were detected by Western blotting.Mean-while, the effect of miR-19a on the generation of ketone body was measured by beta-hydroxybutyric acid (β-OHB) detec-tion assay.RESULTS:The mRNA level of miR-19a was dramatically elevated by the transfection of miR-19a mimics, and sharply decreased by the transfection of miR-19a inhibitor (P<0.05).PPARαwas found as a potential target of miR-19a, and dual luciferase reporter assay and Western blotting confirmed the regulatory effect of miR-19a on the expression of PPARα, with the protein level changes of ACADM and CPT1A.miR-19a mimics down-regulated, while miR-19a inhibitor up-regulated the concentration ofβ-OHB in LO2 cells (P<0.05).CONCLUSION:miR-19a regulates the lipid catabo-lism of hepatocytes by targeting the PPARαand its 2 downstream rate-limiting enzymes.