MEF2C alleviates acute lung injury in cecal ligation and puncture (CLP)-induced sepsis rats by up-regulating AQP1

Sepsis is a systemic inflammatory response syndrome and leads to patient's death. Objective: To investigate the effect of myocyte enhancer factor 2 (MEF2C) on acute lung injury (ALI) with sepsis and its possible mechanism.The cecal ligation and puncture (CLP)-induced sepsis rat model was established. The lung injury was determined by lung wet-dry weight ratio, the concentration of inflammatory cytokines, including tumor necrosis factor-α (TNF-α), Interlukin (IL)-6, IL-1β, and IL-10, were measured by the enzyme-linked-immunosorbent serologic assay kit. The cell apoptosis was detected by TUNEL staining assay.Interestingly, MEF2C was down-regulated in this model. Moreover, adeno-associated virus (AAV)-MEF2C treatment markedly suppressed TNF-α, IL-1β, and IL-6 concentrations but promoted IL-10 concentration in serum in CLP-challenged rats. Besides, overexpression of MEF2C alleviates CLP-induced lung injury. Interestingly, AAV-MEF2C treatment was confirmed to suppress apoptosis in CLP-induced sepsis rats as well as promote aquaporin APQ1 expression. Mechanistically, the rescue experiments indicated that MEF2C alleviated CLP-induced lung inflammatory response and apoptosis via up-regulating AQP1.In summary, overexpression of MEF2C suppressed CLP-induced lung inflamma-tory response and apoptosis via up-regulating AQP1, providing a novel therapeutic target for sepsis-induced ALI.