miR-335 targets ENPP4 and FADS1 genes to mediate obesity in high-fat mice / 中华内分泌代谢杂志

ABSTRACT

Objective:To detect the differential expression of microRNA(miRNA) in abdominal fat of mice fed with high fat and to explore the role of highly expressed miR-335 in lipid metabolism.Methods:MicroRNA microarray was used to detect the differential expression of miRNAs in abdominal fat of mice fed with high fat. The target genes of miR-335 were predicted by Targetscan, the target genes of ectonucleotide pyrophosphatase/phosphordiester-ase 4(ENPP4) and fatty acid desaturase1(FADS1) were verified with double luciferase reporter system and point mutation test. miR-335 mimics was transfected into 3T3L1 cells to detect the expression of target gene mRNA and protein; Realtime PCR was used to detect the expression levels of miR-335 and target genes in different tissues of mice.Results:After high-fat feeding, the size of mice in the model group was significantly larger than the control group, and the serum total cholesterol and triglyceride levels of mice were significantly increased( P=0.016, P=0.014). miRNAs were differentially expressed in adipose tissues of mice fed with high fat, and the expression of miR-335 increased significantly( P=0.024). Double luciferase reporter system showed that miR-335 combined with the predicted target sites of ENPP4 and FADS1 through the " seed region" to inhibit the expression of ENPP4 and FADS1 genes, and the point mutation test confirmed the binding target sites between miR-335 and ENPP4/FADS1. MiR-335 mimics were transfected into 3T3L1 cells, the expression level of FADS1 mRNA decreased significantly( P=0.038), and the protein levels of ENPP4 and FADS1 decreased significantly( P=0.033, P=0.007). Realtime PCR showed that, miR-335 was significantly higher expressed in liver, brown adipose tissue, and brain after high-fat feeding, especially in white adipose tissue( P=0.002). The expression of ENPP4 and FADS1 in brain( P=0.006, P=0.034) and brown adipose tissue( P=0.014, P=0.037) decreased significantly, and the expression of ENPP4 in liver also decreased significantly after high-fat diet( P<0.001). Conclusion:miR-335 is a miRNA related to lipid metabolism and fat deposition. ENPP4 and FADS1 are the target genes of miR-335.