17 Beta-Estradiol Inhibits Cyclic Strain-Induced Endothelin-1 Gene Expression within Vascular Endothelial Cells
Resource
AMERICAN JOURNAL OF PHYSIOLOGY. HEART AND CIRCULATORY PHYSIOLOGY v.287 n.3 pp.H1254-H1261
Journal
AMERICAN JOURNAL OF PHYSIOLOGY. HEART AND CIRCULATORY PHYSIOLOGY
Journal Volume
v.287
Journal Issue
n.3
Pages
H1254-H1261
Date Issued
2004
Date
2004
Author(s)
CHEN, JIN-JER
CHENG, CHING-FENG
CHAN, PAUL
Abstract
It has been well documented previously that 17beta-estradiol (E-2) exerts a protective effect on cardiovascular tissue. The possible role of E-2 in the regulation of endothelin (ET )-1 production has been previously reported, although the complex mechanisms by which E-2 inhibits ET-1 expression are not completely understood. The aims of this study were to examine whether E-2 was able to alter strain-induced ET-1 gene expression and also to identify the putative underlying signaling pathways that exist within endothelial cells. For cultured endothelial cells, E-2 ( 1 - 100 nM), but not 17 alpha-estradiol, inhibited the level of strain-induced ET- 1 gene expression and also peptide secretion. This inhibitory effect elicited by E-2 was able to be prevented by the coincubation of endothelial cells with the estrogen receptor antagonist ICI-182,780 ( 1 muM). E-2 also inhibited strain- enhanced NADPH oxidase activity and intracellular reactive oxygen species (ROS) generation as measured by the redox- sensitive fluorescent dye 2', 7'-dichlorofluorescin diacetate and the level of extracellular signal-regulated kinase (ERK) phosphorylation. Furthermore, the presence of E -2 and antioxidants such as N- acetylcysteine and diphenylene iodonium were able to elicit a decrease in the level of strain-induced ET-1 secretion, ET-1 promoter activity, ET-1 mRNA, ERK phosphorylation, and activator protein-1 binding activity. In summary, we demonstrated, for the first time, that E-2 inhibits strain- induced ET-1 gene expression, partially by interfering with the ERK pathway via the attenuation of strain-induced ROS generation. Thus this study delivers important new insight regarding the molecular pathways that may contribute to the proposed beneficial effects of estrogen on the cardiovascular system.
Subjects
strain
reactive oxygen species
extracellular signal- regulated kinase
Type
journal article