TY - JOUR
T1 - Lung remodeling and pulmonary hypertension after myocardial infarction
T2 - Pathogenic role of reduced caveolin expression
AU - Jasmin, Jean François
AU - Mercier, Isabelle
AU - Hnasko, Robert
AU - Cheung, Michelle W.C.
AU - Tanowitz, Herbert B.
AU - Dupuis, Jocelyn
AU - Lisanti, Michael P.
N1 - Funding Information:
JFJ was supported by fellowship grants from the ‘‘Fonds de la Recherche en Santédu Québec’’ (FRSQ) and the Canadian Heart and Stroke Foundation.
Funding Information:
This work was supported by grants of the National Institutes of Health (to MPL), the American Heart Association (to MPL), the Canadian Institute of Health Research (to JD) and the Canadian Heart and Stroke Foundation (to JD).
PY - 2004/9/1
Y1 - 2004/9/1
N2 - Objectives: Pulmonary hypertension (PH) and lung structural remodeling are frequent complications of congestive heart failure (CHF). Yet, the molecular mechanisms involved in CHF-induced PH and lung remodeling remain unknown. Caveolins (Cav-1, -2 and -3) are the principal structural proteins of the vesicular invaginations of the plasma membrane, termed caveolae. Mice with homozygous deletion of the caveolin-1 gene (Cav-1(-/-)) have been shown to develop dilated cardiomyopathy, PH and lung structural remodeling, characterized by hypercellularity and thickening of the alveolar septa. However, the physiological relevance of these observations for the pathogenesis of PH and lung remodeling remains to be determined. Methods and results: Here, we investigate the natural behavior of the endogenous caveolin proteins during the development of PH and lung structural remodeling, using a rat model of myocardial infarction (MI). MI was induced in male Wistar rats by ligating the left anterior coronary artery. Two weeks post-MI, rats were anesthetized and hemodynamic and morphometric measurements were obtained. Rats subjected to MI developed marked PH, lung structural remodeling and right ventricular hypertrophy (RVH). Both immunoblot analysis and immunohistochemistry dramatically show that Cav-1 and Cav-2 expression is downregulated to almost undetectable levels in the lungs of post-MI rats. Mechanistically, the reduced expression of caveolins was associated with the increased tyrosine- phosphorylation of the signal transducer and activator of transcription-3 (STAT3) and the upregulation of cyclin D1 and D3 expression. We also show that STAT3 is hyperphosphorylated, and cyclin D1 and D3 levels are dramatically upregulated, in lung tissue samples derived from Cav-1 (-/-)- and Cav-2 (-/-)-deficient mice. Conclusions: Thus, down-modulation of pulmonary Cav-1 and Cav-2 expression in rats subjected to MI may represent an initiating mechanism leading to the activation of the STAT3/Cyclins pathway and, ultimately, to the development of PH and lung structural remodeling.
AB - Objectives: Pulmonary hypertension (PH) and lung structural remodeling are frequent complications of congestive heart failure (CHF). Yet, the molecular mechanisms involved in CHF-induced PH and lung remodeling remain unknown. Caveolins (Cav-1, -2 and -3) are the principal structural proteins of the vesicular invaginations of the plasma membrane, termed caveolae. Mice with homozygous deletion of the caveolin-1 gene (Cav-1(-/-)) have been shown to develop dilated cardiomyopathy, PH and lung structural remodeling, characterized by hypercellularity and thickening of the alveolar septa. However, the physiological relevance of these observations for the pathogenesis of PH and lung remodeling remains to be determined. Methods and results: Here, we investigate the natural behavior of the endogenous caveolin proteins during the development of PH and lung structural remodeling, using a rat model of myocardial infarction (MI). MI was induced in male Wistar rats by ligating the left anterior coronary artery. Two weeks post-MI, rats were anesthetized and hemodynamic and morphometric measurements were obtained. Rats subjected to MI developed marked PH, lung structural remodeling and right ventricular hypertrophy (RVH). Both immunoblot analysis and immunohistochemistry dramatically show that Cav-1 and Cav-2 expression is downregulated to almost undetectable levels in the lungs of post-MI rats. Mechanistically, the reduced expression of caveolins was associated with the increased tyrosine- phosphorylation of the signal transducer and activator of transcription-3 (STAT3) and the upregulation of cyclin D1 and D3 expression. We also show that STAT3 is hyperphosphorylated, and cyclin D1 and D3 levels are dramatically upregulated, in lung tissue samples derived from Cav-1 (-/-)- and Cav-2 (-/-)-deficient mice. Conclusions: Thus, down-modulation of pulmonary Cav-1 and Cav-2 expression in rats subjected to MI may represent an initiating mechanism leading to the activation of the STAT3/Cyclins pathway and, ultimately, to the development of PH and lung structural remodeling.
KW - Caveolin proteins
KW - Cyclins
KW - Lung remodeling
KW - Myocardial infarction
KW - Pulmonary hypertension
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U2 - 10.1016/j.cardiores.2004.05.018
DO - 10.1016/j.cardiores.2004.05.018
M3 - Article
C2 - 15306231
AN - SCOPUS:4043151526
SN - 0008-6363
VL - 63
SP - 747
EP - 755
JO - Cardiovascular research
JF - Cardiovascular research
IS - 4
ER -