Quercetin has been demonstrated to be efficacious in the inhibition of these deleterious processes by means of the inactivation of the SphK1-S1P (sphingosine kinase-1 and sphingosine-1-phosphate) signaling pathway, which is implicated in the pathogenesis of renal fibrosis [143]. The gene discussed is SPHK1; the disease is renal fibrosis.