Hydrogen Sulfide Alleviates Lipopolysaccharide-Induced Diaphragm Dysfunction in Rats by Reducing Apoptosis and Inflammation through ROS/MAPK and TLR4/NF-κB Signaling Pathways

Abstract

Diaphragm dysfunction is an important clinical problem worldwide. Hydrogen sulfide (H ₂S) is involved in many physiological and pathological processes in mammals. However, the effect and mechanism of H ₂S in diaphragm dysfunction have not been fully elucidated. In this study, we detected that the level of H ₂S was decreased in lipopolysaccharide- (LPS-) treated L6 cells. Treatment with H ₂S increased the proliferation and viability of LPS-treated L6 cells. We found that H ₂S decreased reactive oxygen species- (ROS-) induced apoptosis through the mitogen-activated protein kinase (MAPK) signaling pathway in LPS-treated L6 cells. Administration of H ₂S alleviated LPS-induced inflammation by mediating the toll-like receptor-4 (TLR-4)/nuclear factor-kappa B (NF- κB) signaling pathway in L6 cells. Furthermore, H ₂S improved diaphragmatic function and structure through the reduction of inflammation and apoptosis in the diaphragm of septic rats. In conclusion, these findings indicate that H ₂S ameliorates LPS-induced diaphragm dysfunction in rats by reducing apoptosis and inflammation through ROS/MAPK and TLR4/NF- κB signaling pathways. Novel slow-releasing H ₂S donors can be designed and applied for the treatment of diaphragm dysfunction.