CDC6通过CCND1/P53信号通路促进缺血再灌注损伤诱导的压力性损伤中角质形成细胞衰老

Abstract

Pressure injuries develop when prolonged compression of the skin and subcutaneous tissue impairs blood circulation, leading to localized tissue ischemia, degeneration, and ultimately necrosis. Ischemia-reperfusion(I/R) injury is one of the key pathological mechanisms underlying pressure injury formation. While cellular senescence has been implicated in I/R-related pathologies, its role in pressure injury development remains unclear. We aimed to elucidate the mechanisms of keratinocyte senescence in cutaneous I/R injury. An in vitro hypoxia/reoxygenation (H/R) model was employed to simulate I/R injury using human immortalized keratinocytes (HaCaT). H/R induction significantly exacerbated the senescence response, as characterized by reduced cell proliferation, increased apoptosis, elevated SA-β-galactosidase (SA-β-gal) activity, and upregulated expression of senescence markers (p16 and p21). Quantitative proteomic analysis identified CDC6 as a prominently upregulated protein under H/R conditions. siRNA-mediated CDC6 knockdown attenuated keratinocyte senescence, restored G1/S phase cyclin-D1 (CCND1) expression, and suppressed p53 levels, demonstrating its regulatory role in senescence via the p53/CCND1 pathway. Furthermore, protein interaction network analysis and experimental validation revealed CDC6's direct binding with origin recognition complex 2 (ORC2), evidenced by nuclear colocalization (immunofluorescence) and physical interaction (co-immunoprecipitation). Collectively, our findings pioneers the mechanistic elucidation of CDC6 in pressure injury pathology, proposing senescence-targeted interventions as a novel therapeutic strategy for ulcer management.