The molecular mechanisms demonstrated that HKC notably downregulated the protein expression of NADPH oxidase (NOX)-1, NOX-2, NOX-4, α-smooth muscle actin (αSMA), and the p-extracellular signal-regulated kinase (ERK)1/2 by inhibiting the NADPH oxidase/reactive oxygen species (ROS)/ERK signaling pathways in renal tissue in rats with chronic renal failure induced by adenine in vivo [40]. Here, FMO5 is linked to chronic kidney disease.