Damaging effect of cigarette smoke extract on primary cultured human umbilical vein endothelial cells and its mechanism.
OBJECTIVE
To investigate the cellular effects of cigarette smoke extract (CSE) on primarily cultured human umbilical vein endothelial cells (HUVEC).


METHODS
The effects of CSE (5%-20%) and nicotine (10(-4) mol/L) on HUVEC viability, proliferation, angiogenesis and apoptosis were observed.


RESULTS
CSE decreased HUVEC survival rate and angiogenesis after 24 h as well as its proliferation after 48 h in a dose-dependent manner. Moreover, CSE induced apoptosis of HUVEC as indicated in condensation of nuclear chromatin and the presence of hypodiploid DNA. HUVEC incubated with CSE for 24 h gave a significant decrease in the expression of Bcl-2 as well as the decline in the Bcl-2/Bax ratio accompanied with the loss of mitochondrial membrane potential and excess cytosolic calcium. Our study also observed that p53 protein level decreased, rather than increased in cells treated with CSE. Nicotine had no discernible inhibitory effects on the above indices of HUVEC.


CONCLUSIONS
Exposure to CSE other than nicotine causes inhibition of viability, proliferation and differentiation of HUVEC. CSE-induced HUVEC injury is mediated in partthrough accelerated apoptosis but independent of p53 pathway. It appears that mitochondria have played a key role in the apoptosis of HUVEC induced by CSE.
Yang
Yu-Mei
YM
Institute of Materia Medica, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100050, China. yangym9919@hotmail.com
Liu
Geng-Tao
GT
D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D017209:Apoptosis; D002118:Calcium / Q000032:analysis; D002453:Cell Cycle / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000473:pathology; D006801:Humans; D008564:Membrane Potentials; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009538:Nicotine / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D012906:Smoke; D014026:Nicotiana / Q000633:toxicity*; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D014471:Umbilical Veins; D051028:bcl-2-Associated X Protein
D020533:Angiogenesis Inhibitors; C494826:BAX protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D012906:Smoke; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D009538:Nicotine; D002118:Calcium