The protective effect of Bcl-xl overexpression against oxidative stress-induced vascular endothelial cell injury and the role of the Akt/eNOS pathway.
Restenosis after intraluminal or open vascular reconstruction remains an important clinical problem. Vascular endothelial cell (EC) injury induced by oxidative stress plays an important role in the development of intimal hyperplasia. In this study, we sought to evaluate the protective effects of Bcl-xl overexpression in vitro on oxidative stress-induced EC injury and the role of the Akt/endothelial nitric oxide synthase (eNOS) pathway. Human umbilical vein endothelial cells (HUVECs) exposed to hydrogen peroxide (H2O2, 0.5 mM) were used as the experimental oxidative stress model. The Bcl-xl gene was transferred into HUVECs through recombinant adenovirus vector pAdxsi-GFP-Bcl-xl before oxidative treatment. Cell apoptosis was evaluated by Annexin V/propidium iodide and Hoechst staining, caspase-7 and PARP cleavage. Cell viability was assessed using the cell counting kit-8 assay, proliferating cell nuclear antigen (PCNA) immunocytochemical detection and the scratching assay. Expressions of Akt, phospho-Akt and eNOS were detected by Western blotting. Our results showed that H2O2 induced apoptosis and decreased the cell viability of HUVECs. Bcl-xl overexpression significantly protected cells from H2O2-induced cell damage and apoptosis and maintained the cell function. Furthermore, the level of phospho-Akt and eNOS protein expression was significantly elevated when pretreated with Bcl-xl gene transferring. These findings suggest that Bcl-xl overexpression exerts an anti-apoptotic and protective effect on EC function. The Akt/eNOS signaling pathway is probably involved in these processes.
Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, 1# Shuaifuyuan, Dongcheng District, Beijing 100730, China. liucw@vip.sina.com.
Leng
L
Ni
Tianjia
T
Li
Bao
B
Liu
Xitao
X
Song
Genhuan
G
Yang
Linfang
L
Wang
Shiying
S
Miao
Changwei
C
Liu
D017209:Apoptosis / Q000187:drug effects; D023903:Coronary Restenosis / Q000378:metabolism / Q000473:pathology; D042783:Endothelial Cells / Q000187:drug effects / Q000473:pathology; D005786:Gene Expression Regulation / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D052250:Nitric Oxide Synthase Type III / Q000096:biosynthesis*; D051058:Oncogene Protein v-akt / Q000096:biosynthesis*; D018384:Oxidative Stress; D015398:Signal Transduction / Q000187:drug effects; D051020:bcl-X Protein / Q000235:genetics*
C494811:BCL2L1 protein, human; D051020:bcl-X Protein; D006861:Hydrogen Peroxide; D052250:Nitric Oxide Synthase Type III; D051058:Oncogene Protein v-akt