TLR4 and chronic kidney disease: Studies have shown that H2S regulates the toll-like receptor 4 (TLR4)/NF−κB pathway and attenuates cigarette smoke induced pyroptosis (49), and ameliorates chronic renal failure via suppression inflammation and apoptosis by modulating ROS/mitogen-activated protein kinase (MAPK) and NF-κB pathways in rats (50).