|
|
||||||||
1 Department of Physiology, University of Texas Health Science Center, San Antonio, Texas 78229; and 2 Department of Physiology, Northeastern Ohio Universities College of Medicine, Rootstown, Ohio 44272
Aldosterone plays a pathological role in cardiac fibrosis by directly affecting cardiac fibroblasts. Understanding of the cellular mechanisms of aldosterone action in cardiac fibroblasts, however, is rudimentary. One possibility is that aldosterone promotes proliferation of cardiac fibroblasts by activating specific cellular signaling cascades. The current study tests whether aldosterone stimulates proliferation of isolated adult rat cardiac myofibroblasts (RCF) by activating Kirsten Ras (Ki-RasA) and its effector, the MAPK1/2 cascade. Aldosterone (10 nM) significantly increased RCF proliferation. This action was sensitive to the mineralocorticoid receptor (MR) antagonist spironolactone. Expression of MR in RCF and the whole rat heart was confirmed by immunoblotting. Aldosterone significantly increased absolute and active (GTP bound) Ki-RasA levels in RCF. Aldosterone, in addition, significantly increased phospho-c-Raf and phospho-MAPK1/2. The effects of aldosterone on Ki-RasA and phospho-c-Raf proteins were inhibited by spironolactone but not RU-486, suggesting that aldosterone acts via MR. Inhibitors of MEK1/2 and c-Raf prevented aldosterone-induced activation of MAPK1/2 and proliferation. These results show that aldosterone directly increases RCF proliferation through MR-dependent activation of Ki-RasA and its effector, the MAPK1/2 cascade. Activation of cardiac fibroblasts through such a cascade may play a role in the pathological actions exerted by aldosterone on the heart.
mitogen-activated protein kinase; Kirsten Ras; mineralocorticoid receptor; myofibroblast; fibrosis
This article has been cited by other articles:
![]() |
S. Huang, A. Zhang, G. Ding, and R. Chen Aldosterone-induced mesangial cell proliferation is mediated by EGF receptor transactivation Am J Physiol Renal Physiol, June 1, 2009; 296(6): F1323 - F1333. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Goto, F. Otsuka, M. Yamashita, J. Suzuki, H. Otani, H. Takahashi, T. Miyoshi, Y. Mimura, T. Ogura, and H. Makino Enhancement of aldosterone-induced catecholamine production by bone morphogenetic protein-4 through activating Rho and SAPK/JNK pathway in adrenomedullar cells Am J Physiol Endocrinol Metab, April 1, 2009; 296(4): E904 - E916. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. R. Olson, P. E. Shamhart, J. E. Naugle, and J. G. Meszaros Angiotensin II-Induced Extracellular Signal-Regulated Kinase 1/2 Activation Is Mediated by Protein Kinase C{delta} and Intracellular Calcium in Adult Rat Cardiac Fibroblasts Hypertension, March 1, 2008; 51(3): 704 - 711. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Casaclang-Verzosa, B. J. Gersh, and T. S.M. Tsang Structural and functional remodeling of the left atrium: clinical and therapeutic implications for atrial fibrillation. J. Am. Coll. Cardiol., January 1, 2008; 51(1): 1 - 11. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Pochynyuk, J. D. Stockand, and A. Staruschenko Ion Channel Regulation by Ras, Rho, and Rab Small GTPases Experimental Biology and Medicine, November 1, 2007; 232(10): 1258 - 1265. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Otani, F. Otsuka, K. Inagaki, M. Takeda, T. Miyoshi, J. Suzuki, T. Mukai, T. Ogura, and H. Makino Antagonistic effects of bone morphogenetic protein-4 and -7 on renal mesangial cell proliferation induced by aldosterone through MAPK activation Am J Physiol Renal Physiol, May 1, 2007; 292(5): F1513 - F1525. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Peng, O. A. Carretero, T.-D. Liao, E. L. Peterson, and N.-E. Rhaleb Role of N-Acetyl-Seryl-Aspartyl-Lysyl-Proline in the Antifibrotic and Anti-Inflammatory Effects of the Angiotensin-Converting Enzyme Inhibitor Captopril in Hypertension Hypertension, March 1, 2007; 49(3): 695 - 703. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Susic, J. Varagic, J. Ahn, L. Matavelli, and E. D. Frohlich Long-term mineralocorticoid receptor blockade reduces fibrosis and improves cardiac performance and coronary hemodynamics in elderly SHR Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H175 - H179. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Johar, A. C. Cave, A. Narayanapanicker, D. J. Grieve, and A. M. Shah Aldosterone mediates angiotensin II-induced interstitial cardiac fibrosis via a Nox2-containing NADPH oxidase FASEB J, July 1, 2006; 20(9): 1546 - 1548. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. E. Naugle, E. R. Olson, X. Zhang, S. E. Mase, C. F. Pilati, M. B. Maron, H. G. Folkesson, W. I. Horne, K. J. Doane, and J. G. Meszaros Type VI collagen induces cardiac myofibroblast differentiation: implications for postinfarction remodeling Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H323 - H330. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Nagai, K. Miyata, G.-P. Sun, M. Rahman, S. Kimura, A. Miyatake, H. Kiyomoto, M. Kohno, Y. Abe, M. Yoshizumi, et al. Aldosterone Stimulates Collagen Gene Expression and Synthesis Via Activation of ERK1/2 in Rat Renal Fibroblasts Hypertension, October 1, 2005; 46(4): 1039 - 1045. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Ishizawa, Y. Izawa, H. Ito, C. Miki, K. Miyata, Y. Fujita, Y. Kanematsu, K. Tsuchiya, T. Tamaki, A. Nishiyama, et al. Aldosterone Stimulates Vascular Smooth Muscle Cell Proliferation Via Big Mitogen-Activated Protein Kinase 1 Activation Hypertension, October 1, 2005; 46(4): 1046 - 1052. [Abstract] [Full Text] [PDF] |
||||
![]() |
L.-J. Min, M. Mogi, J.-M. Li, J. Iwanami, M. Iwai, and M. Horiuchi Aldosterone and Angiotensin II Synergistically Induce Mitogenic Response in Vascular Smooth Muscle Cells Circ. Res., September 2, 2005; 97(5): 434 - 442. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. K. Rude, T.-A. S. Duhaney, G. M. Kuster, S. Judge, J. Heo, W. S. Colucci, D. A. Siwik, and F. Sam Aldosterone Stimulates Matrix Metalloproteinases and Reactive Oxygen Species in Adult Rat Ventricular Cardiomyocytes Hypertension, September 1, 2005; 46(3): 555 - 561. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Nishiyama, L. Yao, Y. Fan, M. Kyaw, N. Kataoka, K. Hashimoto, Y. Nagai, E. Nakamura, M. Yoshizumi, T. Shokoji, et al. Involvement of Aldosterone and Mineralocorticoid Receptors in Rat Mesangial Cell Proliferation and Deformability Hypertension, April 1, 2005; 45(4): 710 - 716. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. R. Olson, J. E. Naugle, X. Zhang, J. A. Bomser, and J. G. Meszaros Inhibition of cardiac fibroblast proliferation and myofibroblast differentiation by resveratrol Am J Physiol Heart Circ Physiol, March 1, 2005; 288(3): H1131 - H1138. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Juknevicius, Y. Segal, S. Kren, R. Lee, and T. H. Hostetter Effect of aldosterone on renal transforming growth factor-{beta} Am J Physiol Renal Physiol, June 1, 2004; 286(6): F1059 - F1062. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Grossmann, R. Freudinger, S. Mildenberger, A. W. Krug, and M. Gekle Evidence for epidermal growth factor receptor as negative-feedback control in aldosterone-induced Na+ reabsorption Am J Physiol Renal Physiol, June 1, 2004; 286(6): F1226 - F1231. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Tong, R. E. Booth, R. T. Worrell, and J. D. Stockand Regulation of Na+ transport by aldosterone: signaling convergence and cross talk between the PI3-K and MAPK1/2 cascades Am J Physiol Renal Physiol, June 1, 2004; 286(6): F1232 - F1238. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. H. Endemann, R. M. Touyz, M. Iglarz, C. Savoia, and E. L. Schiffrin Eplerenone Prevents Salt-Induced Vascular Remodeling and Cardiac Fibrosis in Stroke-Prone Spontaneously Hypertensive Rats Hypertension, June 1, 2004; 43(6): 1252 - 1257. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. T. Weber From Inflammation to Fibrosis: A Stiff Stretch of Highway Hypertension, April 1, 2004; 43(4): 716 - 719. [Full Text] [PDF] |
||||
![]() |
N. Tsybouleva, L. Zhang, S. Chen, R. Patel, S. Lutucuta, S. Nemoto, G. DeFreitas, M. Entman, B. A. Carabello, R. Roberts, et al. Aldosterone, Through Novel Signaling Proteins, Is a Fundamental Molecular Bridge Between the Genetic Defect and the Cardiac Phenotype of Hypertrophic Cardiomyopathy Circulation, March 16, 2004; 109(10): 1284 - 1291. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. K Shieh, E. Kotlyar, and F. Sam Aldosterone and cardiovascular remodelling: focus on myocardial failure Journal of Renin-Angiotensin-Aldosterone System, March 1, 2004; 5(1): 3 - 13. [Abstract] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |