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 expression, 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.