MiR-92b-3p is Induced by Advanced Glycation End Products and Involved in the Pathogenesis of Diabetic Nephropathy

الملخص EN

Purpose.

The current study aims to examine the effects of advanced glycation end products (AGEs) on the microRNA (miRNA) expression profile in the kidney tissues of rats.

Methods.

Wistar rats were randomly divided into three equal experiment groups: the AGE group, the RSA group, and the control group.

The rats in the AGE group and the RSA group were administered with advanced glycation end products (AGEs) and rat serum albumin (RSA) via the tail vein, respectively, whereas the control group received PBS.

Total RNA was prepared from the rat kidney tissues, and the miRNA expression profiles in different experiment groups were compared by microarray analysis.

The expression levels of selected differential miRNAs were verified by RT-qPCR.

Target gene prediction was conducted using algorithms such as TargetScan, miRanda, and PICTar.

Functional analysis was performed to determine the putative biological roles of the validated miRNAs.

Results.

The microarray study revealed 451 upregulated and 320 downregulated miRNAs in the AGE group compared with the RSA group (p<0.05).

Seven miRNAs, including miR-21-5p, miR-92b-3p, miR-140-3p, miR-196a-5p, miR-181b-5p, miR-186-5p, and miR-192-5p, were screened and verified using RT-qPCR, of which, the change of miR-92b-3p was the most obvious according to the miRNA expression different multiple and p value.

Furthermore, the expression trend of miR-92b-3p measured by RT-qPCR was shown to be consistent with the microarray results.

Bioinformatics analysis and luciferase reporter assay identified Smad7 was a direct target of miR-92b-3p.

Both immunohistochemical and western blotting showed that Smad7 expression was significantly suppressed in the kidney tissues from the AGE group compared with the control and RSA groups.

Conclusion.

The results of the current study suggested that miR-92b-3p could mediate AGE-induced development of renal abnormalities through targeting Smad7 in rats with DN.