Find in Library

Endothelial cell senescence is involved in endothelial dysfunction and vascular diseases. However, the detailed mechanisms of endothelial senescence are not fully understood. Here, we demonstrated that deficiency of developmentally regulated GTP-binding protein 2 (<i>DRG2</i>) induces senescence and dysfunction of endothelial cells. <i>DRG2</i> knockout (KO) mice displayed reduced cerebral blood flow in the brain and lung blood vessel density. We also determined, by Matrigel plug assay, aorta ring assay, and in vitro tubule formation of primary lung endothelial cells, that deficiency in <i>DRG2</i> reduced the angiogenic capability of endothelial cells. Endothelial cells from <i>DRG2</i> KO mice showed a senescence phenotype with decreased cell growth and enhanced levels of p21 and phosphorylated p53, γH2AX, senescence-associated β-galactosidase (SA-β-gal) activity, and senescence-associated secretory phenotype (SASP) cytokines. <i>DRG2</i> deficiency in endothelial cells upregulated arginase 2 (<i>Arg2</i>) and generation of reactive oxygen species. Induction of SA-β-gal activity was prevented by the antioxidant N-acetyl cysteine in endothelial cells from <i>DRG2</i> KO mice. In conclusion, our results suggest that <i>DRG2</i> is a key regulator of endothelial senescence, and its downregulation is probably involved in vascular dysfunction and diseases.