GATA1 regulates the microRNA-328-3p/PIM1 axis via circular RNA ITGB1 to promote renal ischemia/reperfusion injury in HK-2 cells

Acute kidney injury (AKI) is caused by renal ischemia/reperfusion injury (IRI) during kidney transplantation. The levels of both circular RNAs (circRNAs) and microRNAs (miRNAs/miR) appear to be critical for AKI detection. While several RNA interactions in AKI have been found, the regulatory mechanisms between the molecules remain to be fully elucidated. In the present study, miRNA expression profiling analysis was conducted using an online dataset to identify the differentially expressed miRNAs in rats with IRI. miR-328-3p was also found to be downregulated in human kidney-2 (HK-2) cells subjected to hypoxia/reperfusion (H/R), and its overexpression targeting pim-1 proto-oncogene (PIM1) resulted in an increased viability and a reduced apoptosis, as well as in the decreased expression of inflammatory factors upon H/R exposure. Putative targets and circRNAs of miR-328-3p were identified using publically available databases. The inhibition of circRNA integrin beta 1 (ITGB1; circITGB1) suppressed the inflammatory response induced by H/R by sponging miR-328-3p in HK-2 cells. Furthermore, a sequence of the functional ITGB1 promoter was studied for transcription factor GATA binding protein 1 (GATA1) binding sites. GATA1 binds to the ITGB1 promoter, leading to the expression of circITGB1. On the whole, the findings of the present study revealed a regulatory pathway modulating miR-328-3p in IRI, demonstrating that the GATA1-mediated regulation of circITGB1 enhanced the H/R-induced inflammatory response via the miR-328-3p/PIM1 axis.