RUNX3 protects against acute lung injury by inhibiting the JAK2/STAT3 pathway in rats with severe acute pancreatitis.

Acute lung injury (ALI) is the most common complication of severe acute pancreatitis (SAP) in the early stage, which causes systemic inflammatory response and organ damage. Human runt-associated transcription factor 3 gene (RUNX3) has been reported to participate in various inflammatory diseases. However, the exact role of RUNX3 in SAP and its-related ALI remains unclear.To establish the model of SAP, rats were retrogradely injected with 5% sodium taurocholate (1 mg/kg body weight) into the biliary-pancreatic duct. Cytokine level in serum was measured by ELISA, and the polymorphonuclear neutrophil (PMN) was isolated from rat's blood 12 h-post SAP induction.We found RUNX3 expression was significantly decreased with the progression of SAP. Both pancreas damages and cytokine production abilities were reduced in RUXN3-overexpressed SAP rats compared with control rats. Moreover, SAP-associated ALI was also improved upon RUNX3 overexpression in SAP rats. RUNX3 upregulation enhanced PMN apoptosis and inhibited Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) phosphorylation.Our study indicates that RUNX3 protects against SAP and SAP-associated ALI through controlling PMN apoptosis and regulating JAK2/STAT3 signaling pathway. RUNX3 could be regarded as a potent therapeutic target in SAP for future studies.