CIRC_0002131 CONTRIBUTES TO LPS-INDUCED APOPTOSIS, INFLAMMATION, AND OXIDATIVE INJURY IN HK-2 CELLS VIA INHIBITING THE BINDING BETWEEN MIR-942-5P AND OXSR1

Abstract

ABSTRACT Background: Circular RNAs are implicated in the progression of sepsis-associated acute kidney injury (AKI). Circ_0002131 was shown to aggravate cell inflammation and oxidative stress in sepsis-induced AKI. The aim of this study was to investigate the role and underlying mechanism of circ_0002131 in sepsis-induced AKI. Methods: Cell counting Ki-8 assay was used for cell viability detection. Cell apoptosis was measured using flow cytometry. Circ_0002131, microRNA-942-5p (miR-942-5p), and oxidative stress responsive 1 (OXSR1) level analysis was performed through reverse transcription-quantitative polymerase chain reaction assay. The protein levels were examined by western blot. Inflammatory factors were determined using enzyme-linked immunosorbent assay. Oxidative injury was assessed via commercial kits. Target relation was analyzed by dual-luciferase reporter assay and RNA immunoprecipitation assay. Results: HK-2 cell viability was suppressed and apoptosis was enhanced by LPS. Circ_0002131 was highly expressed in LPS-treated HK-2 cells and sepsis-induced AKI patients. LPS-induced apoptosis, inflammation, and oxidative injury of HK-2 cells were attenuated after silence of circ_0002131. Then, miR-942-5p was identified as a target for circ_0002131, and the regulation of circ_0002131 in LPS-induced cell injury was ascribed to reduce miR-942-5p level. In addition, circ_0002131 targeted miR-942-5p to elevate OXSR1 expression. MiR-942-5p prevented LPS-evoked HK-2 cell injury via targeting OXSR1. Conclusion: All results demonstrated that circ_0002131 promoted LPS-mediated HK-2 cell injury via miR-942-5p–mediated upregulation of OXSR1, suggesting that the circ_0002131/miR-942-5p/OXSR1 axis was related to sepsis-induced AKI progression.