Emodin alleviates lung ischemia–reperfusion injury by suppressing gasdermin D-mediated pyroptosis in rats

Abstract

Background: Pyroptosis refers to programmed cell death associated with inflammation. Emodin has been reported to alleviate lung injuries caused by various pathological processes and attenuate ischemia–reperfusion (I/R) injuries in diverse tissues. Methods: Lewis rats were assigned into the sham, the I/R, and the I/R + emodin groups. Emodin and phosphate-buffered saline were intraperitoneally injected into rats of the emodin group and I/R group for 30 min, respectively. These rats were then subjected to left thoracotomy followed by 90-min clamping of the left hilum and 120-min reperfusion. Sham-operated rats underwent 210-min ventilation. Lung functions, histological changes, lung edema, and cytokine levels were assessed. Protein levels were measured by western blotting. Immunofluorescence staining was conducted to evaluate pyroptosis. Results: Emodin alleviated the I/R-induced lung dysfunction, lung damages, and inflammation. Protective effects of emodin against I/R-mediated endothelial pyroptosis was observed in vivo and in vitro. Mechanistically, emodin inactivated the TLR4/MyD88/NF-κB/NLRP3 pathway. Conclusion: Emodin attenuates lung ischemia–reperfusion injury by inhibiting GSDMD-mediated pyroptosis in rats.