BANP Participates in the Chronic Intermittent Hypoxia-Induced Senescence of Vascular Endothelial Cells by Promoting P53 Phosphorylation and Nuclear Retention

Abstract

<b><i>Introduction:</i></b> The objective of this study was to examine the potential induction of senescence in vascular endothelial cells (VECs) by chronic intermittent hypoxia (CIH), a defining characteristic of obstructive sleep apnea (OSA). This investigation seeks to elucidate the underlying mechanisms that contribute to the development of cardiovascular diseases in patients with OSA, with a particular focus on CIH-induced vascular aging. <b><i>Methods:</i></b> The BioSpherix-OxyCycler system was used to establish models of CIH in both rats and human umbilical vein endothelial cells (HUVECs). To assess VECs’ senescence, various methods were employed including EdU incorporation assay, cell cycle analysis, senescence-associated β-galactosidase (SA-β-gal) staining, and senescence protein testing. Vascular aging was evaluated through measurements of carotid-femoral pulse wave velocity, intima-media thickness, and Ki67 immunohistochemical staining. In order to identify the molecular mechanisms associated with CIH-induced senescence in VECs, a bioinformatics study was conducted utilizing the Gene Expression Omnibus database. <b><i>Results:</i></b> Under conditions of CIH, HUVECs exhibited inhibited proliferation, arrested cell cycle, increased activity of SA-β-gal, and elevated expression levels of p53 and p21 compared to HUVECs under normoxic conditions. Similarly, rats exposed to CIH displayed increased carotid-femoral pulse wave velocity, intima-media thickness, vascular permeability, and SA-β-gal activity in VECs, along with decreased expression of arterial Ki67. BTG3-associated protein (BANP) was found to be highly expressed in CIH-induced VECs. Furthermore, the overexpression of BANP resulted in the senescence of VECs, along with elevated levels of p53 phosphorylation and nuclear localization. <b><i>Conclusions:</i></b> These findings demonstrate that CIH can induce VECs senescence and contribute to vascular aging. Additionally, BANP can induce VECs senescence by promoting p53 phosphorylation and nuclear retention. These discoveries offer novel insights into the increased cardiovascular risk associated with OSA, thereby presenting new possibilities for therapeutic intervention.