Protective Effects of PPAR on Renal Ischemia-Reperfusion Injury by Regulating miR-21.

Renal ischemia-reperfusion injury (RIRI) is a common pathological process that causes kidney injury. Previous studies have indicated that both peroxisome proliferator-activated receptor (PPAR) and microRNA-21 (miR-21) exert protective effects against RIRI. However, their relationship is not well understood. In the present study, we investigated the role of the PPAR/miR-21/programmed cell death 4 (PDCD4) axis in IRI, both and . cell hypoxia/reoxygenation (H/R) and RIRI models were established, and cell viability, cell apoptosis, and key molecule expression profiles were analyzed. Our results showed that both PPAR and miR-21 had protective effects against RIRI to varying degrees, and there was an interaction between PPAR and miR-21. PPAR could promote the expression of miR-21 and partially protect against RIRI by reducing the level of the miR-21 target protein (PDCD4). Our findings underscore the potential utility of future clinical investigations of PPAR activation and targeting of the underlying miR-21/PDCD4/caspase-3 pathway, which may participate in the pathogenesis of human IRI.