Glutaredoxin 1 enhances endothelial cell angiogenesis by reducing VEGFA S-glutathionylation and delays vascular endothelial cell senescence

Abstract

Vascular senescence serves as a critical pathophysiological foundation for systemic organ aging in humans. Glutaredoxin 1 (Grx1), a key regulator of intracellular redox signaling, plays a critical role in modulating cellular senescence. In this study, we observed significantly reduced Grx1 expression in the aortic endothelial cells of naturally senescent SD rats and D-gal-induced senescent vascular endothelial cells compared to control groups. We established a stable Grx1 knockdown vascular endothelial cell model using lentivirus-mediated RNA interference. Grx1 knockdown significantly upregulated aging markers (p16, p21, p53, p65) and endogenous SASP-related factors (IL-6, TNF-α, MCP-1, TGF-β, PAI-1), while downregulating SIRT1, Lamin B1, angiogenesis-related factors (VEGFA, ANG1, ANG2, VEGFR2, TIE-2) and the GSH/GSSG ratio. Meanwhile, Grx1 knockdown markedly enhanced S-glutathionylation of VEGFA, increasing its affinity for the soluble receptor VEGFR1 over the membrane-bound VEGFR2. This modification altered VEGFA conformation, blocked downstream signaling, promoted VEGFA degradation via the ubiquitin-proteasome pathway, and ultimately suppressed endothelial cell angiogenesis. Interestingly, overexpression of Grx1 reversed the trends in age-related proteins, factors and angiogenesis activity observed in Grx1 knockdown group. These findings demonstrate that Grx1 knockdown induces senescence and dysfunction in vascular endothelial cells, while Grx1 overexpression reverses these detrimental effects. In conclusion, Grx1 serves as a critical regulator in combating vascular endothelial cell aging. Targeting Grx1 may therefore represent a promising therapeutic strategy for preventing and treating vascular aging-related diseases.

Keywords: Angiogenesis; Endothelial cells; Glutaredoxin 1; S-Glutathionylation; Vascular senescence.