Antioxidant effect of estrogen on bovine aortic endothelial cells.
OBJECTIVE
This study discussed the role of estrogen as an antioxidant in the damage of vascular endothelial cells.


METHODS
We treated bovine aortic endothelial cells (bAEC) either with 1mM of H(2)O(2) alone or with 1 microM of 17beta-estradiol (E(2)) for 24h followed by 1mM of H(2)O(2) for 3h. The cell survival was evaluated by MTT assay, cellular apoptosis by fluorescence activated cell sorter (FACS) and Hoechst 33342 staining, oxidative stress by intracellular reactive oxygen species (ROS) and apoptosis after oxidative stress by western blotting for phospho-p38, p38, and Bcl-2.


RESULTS
MTT assay showed that bAEC viability was reduced to 55.7+/-3.0% and 39.1+/-3.7% after 30 and 60 min of H(2)O(2) treatment, respectively. E(2) and H(2)O(2) treated cells did not show significant decrease in the cell survival. Similarly the FACS analysis and Hoechst 33342 stain showed that the latter decreased cellular apoptosis induced by H(2)O(2). Intracellular ROS increased by 181.6+/-68.9% in the former and by 37.0+/-3.9% in the latter (P<0.05). The expression of phospho-p38 mitogen-activated protein kinase (MAPK) was higher in the latter.


CONCLUSIONS
E(2) mediates antioxidant effects on the oxidative stress induced by H(2)O(2). This antioxidant effect on bAEC may elucidate the scientific basis of hormone therapy for maintaining cardiovascular integrity in postmenopausal women.
Song
Jae-Yen
JY
Department of Obstetrics and Gynecology, The Catholic University of Korea, Republic of Korea.
Kim
Min-Joung
MJ
Jo
Hyun-Hee
HH
Hwang
Seong-Jin
SJ
Chae
Boah
B
Chung
Jae-Eun
JE
Kwon
Dong-Jin
DJ
Lew
Young-Ok
YO
Lim
Yong-Taik
YT
Kim
Jang-Heub
JH
Kim
Jin-Hong
JH
Kim
Mee-Ran
MR
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001011:Aorta / Q000166:cytology / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D002318:Cardiovascular Diseases / Q000517:prevention & control; D002319:Cardiovascular System / Q000187:drug effects; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology*; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D007093:Imidazoles / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008593:Menopause / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
D000975:Antioxidants; D007093:Imidazoles; D011725:Pyridines; D017382:Reactive Oxygen Species; D004958:Estradiol; D006861:Hydrogen Peroxide; C093642:SB 203580