This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Diep, Q. N. Articles by Schiffrin, E. L. Search for Related Content PubMed PubMed Citation Articles by Diep, Q. N. Articles by Schiffrin, E. L. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Dietary Fats Related Collections Remodeling

(Hypertension. 2000;35:287.)
© 2000 American Heart Association, Inc.

Scientific Contributions

Endothelin-1 Attenuates 3 Fatty Acid–Induced Apoptosis by Inhibition of Caspase 3

Quy N. Diep; Hope D. Intengan; Ernesto L. Schiffrin

From the MRC Multidisciplinary Research Group on Hypertension, Clinical Research Institute of Montreal, University of Montreal, Montreal, Quebec, Canada.

Correspondence to Ernesto L. Schiffrin, MD, PhD, FRCPC, Clinical Research Institute of Montreal, 110 Pine Ave W, Montreal, Quebec, Canada H2W 1R7. E-mail schiffe{at}ircm.qc.ca

Abstract—Endothelin-1 (ET-1) may be involved in the induction of vascular hypertrophy in hypertension. ET-1 may also modulate vascular growth through the exertion of antiapoptotic effects. The 3 fatty acids (3 FAs), which have antiproliferative effects in various cell types, may have a beneficial role in hypertension. We tested the hypothesis that ET-1 could act as a survival factor against 3 FA–induced apoptosis and attempted to elucidate possible molecular mechanisms underlying the protective action of ET-1 on docosahexaenoic acid (DHA)-induced apoptosis. Mesenteric vascular smooth muscle cells were stimulated with DHA, a representative 3 FA. Dose-response curves of DHA at different apoptotic stages were assessed with the use of flow cytometry: (1) very early: plasma membrane phosphatidylserine (PS) translocation; (2) early: change in mitochondrial transmembrane potential (m); and (3) late: cell cycle analysis. Expression of the proapoptotic protein bax and the antiapoptotic protein bcl-2 was determined with Western blot assay. The activity and the expression of caspase 3, which is a critical proteolytic enzyme involved in the death-signaling pathway, were evaluated with a fluorometric immunosorbent enzyme assay and Western blot analysis, respectively. Apoptosis, which was detected with PS translocation, m disruption, and cell cycle analysis, was increased dose dependently by DHA. DHA-induced apoptosis was attenuated through exposure to ET-1 for 1 hour before DHA in cell cycle analysis. The interference of ET-1 with DHA-induced apoptosis, as detected with cell cycle analysis, was not apparent at the membrane (PS translocation) or the mitochondrial (m) level. The increase in bax/bcl-2 ratio in DHA-stimulated cells was not affected by ET-1. However, DHA increased both caspase 3 activity and the active forms of caspase 3 (20 and 17 kDa), resulting in enhanced DNA fragmentation as shown through Hoechst staining and fluorescence microscopy, which were attenuated by ET-1 pretreatment. In conclusion, DHA, an 3 FA, induced apoptosis in vascular smooth muscle cells in a dose-dependent manner. ET-1 exerted important protective effects through the attenuation of DHA-induced caspase 3 activation and subsequent DNA fragmentation in the late stages of apoptosis.

Key Words: muscle, smooth, vascular • endothelin • remodeling • fatty acids

This article has been cited by other articles:

				W. O. Sampaio, C. Henrique de Castro, R. A.S. Santos, E. L. Schiffrin, and R. M. Touyz Angiotensin-(1-7) Counterregulates Angiotensin II Signaling in Human Endothelial Cells Hypertension, December 1, 2007; 50(6): 1093 - 1098. [Abstract] [Full Text] [PDF]

				W. O. Sampaio, R. A. Souza dos Santos, R. Faria-Silva, L. T. da Mata Machado, E. L. Schiffrin, and R. M. Touyz Angiotensin-(1-7) Through Receptor Mas Mediates Endothelial Nitric Oxide Synthase Activation via Akt-Dependent Pathways Hypertension, January 1, 2007; 49(1): 185 - 192. [Abstract] [Full Text] [PDF]

				E. L. Schiffrin Peroxisome proliferator-activated receptors and cardiovascular remodeling Am J Physiol Heart Circ Physiol, March 1, 2005; 288(3): H1037 - H1043. [Abstract] [Full Text] [PDF]

				E. L. Schiffrin, F. Amiri, K. Benkirane, M. Iglarz, and Q. N. Diep Peroxisome Proliferator-Activated Receptors: Vascular and Cardiac Effects in Hypertension Hypertension, October 1, 2003; 42(4): 664 - 668. [Abstract] [Full Text] [PDF]

				D. Del Bufalo, V. Di Castro, A. Biroccio, M. Varmi, D. Salani, L. Rosano, D. Trisciuoglio, F. Spinella, and A. Bagnato Endothelin-1 Protects Ovarian Carcinoma Cells against Paclitaxel-Induced Apoptosis: Requirement for Akt Activation Mol. Pharmacol., March 1, 2002; 61(3): 524 - 532. [Abstract] [Full Text] [PDF]

				G. S. Filippatos, N. Gangopadhyay, O. Lalude, N. Parameswaran, S. I. Said, W. Spielman, and B. D. Uhal Regulation of apoptosis by vasoactive peptides Am J Physiol Lung Cell Mol Physiol, October 1, 2001; 281(4): L749 - L761. [Abstract] [Full Text] [PDF]

				A. Orlandi, A. Francesconi, D. Cocchia, A. Corsini, and L. G. Spagnoli Phenotypic Heterogeneity Influences Apoptotic Susceptibility to Retinoic Acid and cis-Platinum of Rat Arterial Smooth Muscle Cells In Vitro : Implications for the Evolution of Experimental Intimal Thickening Arterioscler Thromb Vasc Biol, July 1, 2001; 21(7): 1118 - 1123. [Abstract] [Full Text] [PDF]

				Q. N. Diep, R. M. Touyz, and E. L. Schiffrin Docosahexaenoic Acid, a Peroxisome Proliferator-Activated Receptor-{alpha} Ligand, Induces Apoptosis in Vascular Smooth Muscle Cells by Stimulation of p38 Mitogen-Activated Protein Kinase Hypertension, November 1, 2000; 36(5): 851 - 855. [Abstract] [Full Text] [PDF]