Novel Mechanism of the Pericyte-Myofibroblast Transition in Renal Interstitial Fibrosis: Core Fucosylation Regulation

Abstract

Pericytes have been identified as a major source of myofibroblasts in renal interstitial fibrosis (RIF). The overactivation of several signaling pathways, mainly the TGF-β and PDGF pathways, initiates the pericyte-myofibroblast transition during RIF. Key receptors in these two pathways have been shown to be modified by fucosyltransferase 8 (FUT8), the enzyme that catalyzes core fucosylation. This study postulated that core fucosylation might play an important role in regulating the pericyte transition in RIF. The data showed that core fucosylation increased with the extent of RIF in patients with IgA nephropathy (IgAN). Similarly, core fucosylation of pericytes increased in both a unilateral ureteral occlusion (UUO) mouse model and an in vitro model of pericyte transition. Inhibition of core fucosylation by adenoviral-mediated FUT8 shRNA in vivo and FUT8 siRNA in vitro significantly reduced pericyte transition and RIF. In addition, the activation of both the TGF-β/Smad and PDGF/ERK pathways was blocked by core fucosylation inhibition. In conclusion, core fucosylation may regulate the pericyte transition in RIF by modifying both the TGF-β/Smad and PDGF/ERK pathways. Glycosylation might be a novel "hub" target to prevent RIF.