AGXT and medical procedure: Ceramide formation via aSMase [26,70] and SPT [74] induced ROS production by activating Rac guanosine triphosphatase (GTPase) and NADH/NADPH oxidase in oxidant-induced kidney injury, while an inhibitor of SPT, myriocin, which inhibits de novo ceramide synthesis, and an inhibitor of NADPH oxidase, apocynin, inhibited ROS generation and glomerular injury [74,75].