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bioRxiv · 10.1101/2023.08.04.552075

Colchicine inhibited oxidative stress-induced endothelial cell senescence via blocking NF-κB and MAPKs: Implications in vascular diseases

Abstract

Smoking, alcohol abuse, and hypertension are - among others the potential risk factors for cardiovascular diseases. These risk factors generate oxidative stress and cause oxidative stress-induced DNA damage, resulting in cellular senescence and senescence-associated secretory phenotype (SASP). The SASP factors in feed-forward response exacerbate inflammation and cause tissue remodeling, resulting in atherosclerotic plaque formation and rupture. Colchicine was used to ameliorate oxidative stress-induced senescence in human umbilical vein endothelial cells. Oxidative stress was quantified by reactive oxygen species (ROS) assay and oxidative stress-induced DNA damage was analyzed by 8-OHDG immunofluorescence staining. Endothelial cell senescence was visualized by {beta}-gal staining. The relative mRNA expression was quantified by qPCR and protein analysis was performed by Western blot. Colchicine inhibited ROS generation and mitigated oxidative stress-induced DNA damage. It dampened oxidative stress-induced endothelial cell senescence and improved the expression of DNA repair protein KU80 and aging marker Lamin B1. The drug attenuated the expression of senescence marker P21 at mRNA and protein levels. The pathway analysis showed that colchicine inhibited NF-{kappa}B and MAPKs pathways and subdued mTOR activation. Colchicine also attenuated mRNA expression of interleukin (IL)-1{beta}, IL-6, IL-8 MCP-1, ICAM-1, and E-selectin. Furthermore, colchicine reduced the mRNA and protein expression of matrix metalloproteinase (MMP-2). In summary, colchicine blocked oxidative stress-induced senescence and SASP by inhibiting the activation of NF-{kappa}B and MAPKs pathways.

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BibTeXRIS

Zhou, H., Khan, D., Hussain, S. M., Gerdes, N., Hagenbeck, C., Rana, M., Cornelius, J. F., Muhammad, S.. 2023-08-06. Colchicine inhibited oxidative stress-induced endothelial cell senescence via blocking NF-κB and MAPKs: Implications in vascular diseases. https://doi.org/10.1101/2023.08.04.552075

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