Excessive apoptosis of podocytes caused by dysregulation of microRNA-182-5p and CD2AP confers to an increased risk of diabetic nephropathy

Abstract

The functions of miR-182-5p in the pathogenesis of diabetic nephropathy (DN) remain largely unclear. Here, we studied the roles and relationship between miR-182-5p and CD2AP in the development of DN. We used real-time polymerase chain reaction (PCR) to compare miR-182-5p expression between DN and control groups, while computational analysis and luciferase assays were used to confirm CD2AP as a miR-182-5p target. Western blot and real-time PCR were then used to measure the messenger RNA (mRNA) and protein expression of CD2AP in the presence of miR-182-5p. The results showed that miR-182-5p was highly expressed in cells isolated from people with DN. In addition, the luciferase activity of cells transfected with wild-type/mutant CD2AP confirmed CD2AP as a direct target of miR-182-5p. The expression levels of CD2AP mRNA and protein were much lower in the DN group compared with that in the normal group. In addition, the expression levels of CD2AP mRNA and protein were evidently increased by a miR-182-5p inhibitor, but notably downregulated by miR-182-5p mimics or CD2AP small interfering RNA (siRNA). Furthermore, miR-182-5p and CD2Ap siRNA significantly reduced the survival rate and viability of transfected cells, while the miR-182-5p inhibitor exhibited an opposite effect. These findings indicated the presence of a negative regulatory relationship between miR-182-5p and CD2AP in podocytes cells and suggested that the overexpression of miR-182-5p contributes to the pathogenesis of DN.

Keywords: CD2AP; apoptosis; diabetic nephropathy; microRNA-182-5p; podocyte.