miR-30a-5p mitigates autophagy by regulating the Beclin-1/ATG16 pathway in renal ischemia/reperfusion injury

Abstract

Renal ischemia/reperfusion (I/R) injury often occurs during multiple organ failure and sepsis, and autophagy may serve a role in I/R injury. The aim of the present study was to explore the effect of microRNA (miR)-30a-5p on autophagy in renal I/R injury. miR-30a-5p and autophagy-related protein expression levels in renal I/R injury mouse models and in hypoxia/re-oxygenation HK-2 cell models were determined using reverse transcription-quantitative PcR or western blotting; apoptosis was analyzed using flow cytometry. The effects of miR-30a-5p, Beclin-1 and autophagy-related gene 16 (ATG16) on the proliferation and autophagy of HK-2 cells were analyzed through gain- and loss-of-function studies. miR-30a-5p expression was significantly decreased after renal I/R injury in the in vivo and in vitro experiments. Renal I/R injury led to upregulated expression of autophagy-related proteins microtubule-associated protein light chain 3 (LC3)-Ⅱ and Beclin-1, and downregulated expression of p62. miR-30a-5p overexpression decreased the number of Lc3 punctae, decreased HK-2 cell apoptosis, increased p62 expression and decreased LC3-Ⅱ and Beclin-1 expression. Inhibition of miR-30a-5p exhibited the opposite effects. A luciferase reporter assay demonstrated that miR-30a-5p targeted Beclin-1. Beclin-1 overexpression led to a significant increase in LC3-Ⅱ expression and a decrease in p62 expres- sion, as well as a significant increase in apoptosis. Beclin-1 overexpression also increased the protein expression level of ATG16. downregulation of Beclin-1 decreased the expression of LC3-Ⅱ, elevated the p62 level and decreased apoptosis. ATG16 knockdown showed similar effects as those of Beclin-1 downregulation. In conclusion, miR-30a-5p was increased in renal I/R injury and might mitigate autophagy by regulating the Beclin-1/ATG16 pathway.