MicroRNA‐214‐5p aggravates sepsis‐related acute kidney injury in mice

Acute kidney injury (AKI) is a devastating comorbidity in sepsis and correlates with a very poor prognosis and increased mortality. Currently, we use lipopolysaccharide (LPS) to establish sepsis-related AKI and try to demonstrate the pathophysiological role of microRNA-214-5p (miR-214-5p) in this process. Mice were intravenously injected with the miR-214-5p agomir, antagomir or negative controls for three consecutive days and then received a single intraperitoneal injection of LPS (10 mg/kg) for 24 h to induce AKI. Besides, the Boston University mouse proximal tubular cell lines were stimulated with LPS (10 μg/ml) for 8 h to investigate the role of miR-214-5p in vitro. To inhibit adenosine monophosphate-activated protein kinase (AMPK), compound C (CpC) was used in vivo. For glucagon-like peptide-1 receptor (GLP-1R) silence, cells were transfected with the small interfering RNA against GLP-1R. miR-214-5p level was upregulated in LPS-treated kidneys and proximal tubular cell lines. The miR-214-5p antagomir reduced LPS-induced renal inflammation and oxidative stress, thereby preventing renal damage and dysfunction. In contrast, the miR-214-5p agomir aggravated LPS-induced inflammation, oxidative stress and AKI in vivo and in vitro. Mechanistically, we found that the miR-214-5p antagomir prevented septic AKI via activating AMPK and that CpC treatment completely abrogated its renoprotective effect in mice. Further detection showed that miR-214-5p directly bound to the 3'-untranslational region of GLP-1R to inhibit GLP-1R/AMPK axis. Our data identify miR-214-5p as a promising therapeutic candidate to treat sepsis-related AKI.