1
|
Fazio A, Evangelisti C, Cappellini A, Mongiorgi S, Koufi FD, Neri I, Marvi MV, Russo M, Ghigo A, Manzoli L, Fiume R, Ratti S. Emerging Roles of Phospholipase C Beta Isozymes as Potential Biomarkers in Cardiac Disorders. Int J Mol Sci 2023; 24:13096. [PMID: 37685903 PMCID: PMC10487445 DOI: 10.3390/ijms241713096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 09/10/2023] Open
Abstract
Phospholipase C (PLC) enzymes represent crucial participants in the plasma membrane of mammalian cells, including the cardiac sarcolemmal (SL) membrane of cardiomyocytes. They are responsible for the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) into 1,2-diacylglycerol (DAG) and inositol (1,4,5) trisphosphate (Ins(1,4,5)P3), both essential lipid mediators. These second messengers regulate the intracellular calcium (Ca2+) concentration, which activates signal transduction cascades involved in the regulation of cardiomyocyte activity. Of note, emerging evidence suggests that changes in cardiomyocytes' phospholipid profiles are associated with an increased occurrence of cardiovascular diseases, but the underlying mechanisms are still poorly understood. This review aims to provide a comprehensive overview of the significant impact of PLC on the cardiovascular system, encompassing both physiological and pathological conditions. Specifically, it focuses on the relevance of PLCβ isoforms as potential cardiac biomarkers, due to their implications for pathological disorders, such as cardiac hypertrophy, diabetic cardiomyopathy, and myocardial ischemia/reperfusion injury. Gaining a deeper understanding of the mechanisms underlying PLCβ activation and regulation is crucial for unraveling the complex signaling networks involved in healthy and diseased myocardium. Ultimately, this knowledge holds significant promise for advancing the development of potential therapeutic strategies that can effectively target and address cardiac disorders by focusing on the PLCβ subfamily.
Collapse
Affiliation(s)
- Antonietta Fazio
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Camilla Evangelisti
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Alessandra Cappellini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Sara Mongiorgi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Foteini-Dionysia Koufi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Irene Neri
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Maria Vittoria Marvi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Michele Russo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center “Guido Tarone”, University of Torino, 10126 Torino, Italy; (M.R.); (A.G.)
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center “Guido Tarone”, University of Torino, 10126 Torino, Italy; (M.R.); (A.G.)
| | - Lucia Manzoli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Roberta Fiume
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| | - Stefano Ratti
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy; (A.F.); (C.E.); (A.C.); (S.M.); (F.-D.K.); (I.N.); (M.V.M.); (L.M.)
| |
Collapse
|
2
|
Upregulation of Phospholipase C Gene Expression Due to Norepinephrine-Induced Hypertrophic Response. Cells 2022; 11:cells11162488. [PMID: 36010565 PMCID: PMC9406906 DOI: 10.3390/cells11162488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/04/2022] [Accepted: 08/09/2022] [Indexed: 11/28/2022] Open
Abstract
The activation of phospholipase C (PLC) is thought to have a key role in the cardiomyocyte response to several different hypertrophic agents such as norepinephrine, angiotensin II and endothelin-1. PLC activity results in the generation of diacylglycerol and inositol trisphosphate, which are downstream signal transducers for the expression of fetal genes, increased protein synthesis, and subsequent cardiomyocyte growth. In this article, we describe the signal transduction elements that regulate PLC gene expression. The discussion is focused on the norepinephrine- α1-adrenoceptor signaling pathway and downstream signaling processes that mediate an upregulation of PLC isozyme gene expression. Evidence is also indicated to demonstrate that PLC activities self-regulate the expression of PLC isozymes with the suggestion that PLC activities may be part of a coordinated signaling process for the perpetuation of cardiac hypertrophy. Accordingly, from the information provided, it is plausible that specific PLC isozymes could be targeted for the mitigation of cardiac hypertrophy.
Collapse
|
3
|
Tappia PS, Ramjiawan B, Dhalla NS. Role of Phospholipase C in Catecholamine-induced Increase in Myocardial Protein Synthesis. Can J Physiol Pharmacol 2022; 100:945-955. [PMID: 35767883 DOI: 10.1139/cjpp-2022-0189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of the α1-adrenoceptor-(α1-AR) by norepinephrine results in the G-protein (Gqα) mediated increase in the phosphoinositide-specific phospholipase C (PLC) activity. The byproducts of PLC hydrolytic activity, namely, 1,2-diacylglycerol and inositol-1,4,5-trisphosphate, are important downstream signal transducers for increased protein synthesis in the cardiomyocyte and the subsequent hypertrophic response. In this article, evidence is outlined to demonstrate the role of cardiomyocyte PLC isozymes in the catecholamine-induced increase in protein synthesis by using a blocker of α1-AR and an inhibitor of PLC. The discussion will be focused on the α1-AR-Gqα-PLC-mediated hypertrophic signaling pathway from the viewpoint that it may compliment the other β1-AR-Gs protein-adenylyl cyclase signal transduction mechanisms in the early stages of cardiac hypertrophy development, but may become more relevant at the late stage of cardiac hypertrophy. From the information provided here, it is suggested that some specific PLC isozymes may potentially serve as important targets for the attenuation of cardiac hypertrophy in the vulnerable patient population at-risk for heart failure.
Collapse
Affiliation(s)
- Paramjit S Tappia
- Asper Clinical Research Institute, St. Boniface Hospital, Office of Clinical Research, Winnipeg, Manitoba, Canada;
| | - Bram Ramjiawan
- University of Manitoba, Faculty of Medicine, Winnipeg, Manitoba, Canada;
| | - Naranjan S Dhalla
- St Boniface Hospital Research, 120927, Institute of Cardiovascular Sciences, Albrechtsen Research Centre, Winnipeg, Manitoba, Canada;
| |
Collapse
|
4
|
Tappia P, Elimban V, Dhalla N. Involvement of phospholipase C in the norepinephrine-induced hypertrophic response in Cardiomyocytes. SCRIPTA MEDICA 2022. [DOI: 10.5937/scriptamed53-36527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Norepinephrine (NE) is known to mediate cardiomyocyte hypertrophy through the G protein coupled a1 -adrenoceptor (a1 -AR) and the activation of the phosphoinositide-specific phospholipase C (PLC). Since the by-products of PLC activity are important downstream signal transducers for cardiac hypertrophy, the role of and the regulatory mechanisms involved in the activation of PLC isozymes in cardiac hypertrophy are highlighted in this review. The discussion is focused to underscore PLC in different experimental models of cardiac hypertrophy, as well as in isolated adult and neonatal cardiomyocytes treated with NE. Particular emphasis is laid concerning the a1 -AR-PLC-mediated hypertrophic signalling pathway. From the information provided, it is evident that the specific activation of PLC isozymes is a primary signalling event in the a1 -AR mediated response to NE as well as initiation and progression of cardiac hypertrophy. Furthermore, the possibility of PLC involvement in the perpetuation of cardiac hypertrophy is also described. It is suggested that specific PLC isozymes may serve as viable targets for the prevention of cardiac hypertrophy in patient population at-risk for the development of heart failure.
Collapse
|
5
|
Liu Y, Chen F, Ji L, Zhang L, Xu YJ, Dhalla NS. Role of lysophosphatidic acid in vascular smooth muscle cell proliferation. Can J Physiol Pharmacol 2019; 98:103-110. [PMID: 31369714 DOI: 10.1139/cjpp-2019-0264] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Lysophosphatidic acid (LPA) is an important lipid molecule for signal transduction in cell proliferation. Although the effects of LPA on vascular smooth muscle (VSM) cell growth have been reported previously, the underlying mechanisms of its action are not fully understood. The present study was undertaken to investigate the effects of some inhibitors of different protein kinases and other molecular targets on LPA-induced DNA synthesis as well as gene expression in the aortic VSM cells. The DNA synthesis was studied by the [3H]thymidine incorporation method and the gene expression was investigated by the real-time PCR technique. It was observed that the LPA-induced DNA synthesis was attenuated by inhibitors of protein kinase C (PKC) (staurosporine, calphostin C, and bisindolylmaleimide), phosphoinositide 3-kinase (PI3K) (wortmannin and LY294002), and ribosomal p70S6 kinase (p70S6K) (rapamycin). The inhibitors of guanine protein coupled receptors (GPCR) (pertussis toxin), phospholipase C (PLC) (U73122 and D609), and sodium-hydrogen exchanger (NHE) (amiloride and dimethyl amiloride) were also shown to depress the LPA-induced DNA synthesis. Furthermore, gene expressions for PLC β1 isoform, PKC δ and ε isoforms, casein kinase II β isoform, and endothelin-1A receptors were elevated by LPA. These results suggest that the LPA-induced proliferation of VSM cells is mediated through the activation of GPCR and multiple protein kinases as well as gene expressions of some of their specific isoforms.
Collapse
Affiliation(s)
- Yingying Liu
- Department of Nephrology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China, 130033
| | - Feng Chen
- Department of Dermatology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China, 130033
| | - Lei Ji
- Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China, 130033
| | - Lingrui Zhang
- Department of Gastroenterology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China, 130033
| | - Yan-Jun Xu
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Center, and Department of Physiology and Pathophysiology, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R2H 2A6, Canada
| | - Naranjan S Dhalla
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Center, and Department of Physiology and Pathophysiology, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R2H 2A6, Canada
| |
Collapse
|
6
|
Rajtik T, Carnicka S, Szobi A, Giricz Z, O-Uchi J, Hassova V, Svec P, Ferdinandy P, Ravingerova T, Adameova A. Oxidative activation of CaMKIIδ in acute myocardial ischemia/reperfusion injury: A role of angiotensin AT1 receptor-NOX2 signaling axis. Eur J Pharmacol 2015; 771:114-22. [PMID: 26694801 DOI: 10.1016/j.ejphar.2015.12.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/03/2015] [Accepted: 12/11/2015] [Indexed: 12/17/2022]
Abstract
During ischemia/reperfusion (IR), increased activation of angiotensin AT1 receptors recruits NADPH oxidase 2 (NOX2) which contributes to oxidative stress. It is unknown whether this stimulus can induce oxidative activation of Ca(2+)/calmodulin-dependent protein kinase IIδ (CaMKIIδ) leading into the aggravation of cardiac function and whether these effects can be prevented by angiotensin AT1 receptors blockade. Losartan, a selective AT1 blocker, was used. Its effects were compared with effects of KN-93, an inhibitor of CaMKIIδ. Global IR was induced in Langendorff-perfused rat hearts. Protein expression was evaluated by immunoblotting and lipoperoxidation was measured by TBARS assay. Losartan improved LVDP recovery by 25%; however, it did not reduce reperfusion arrhythmias. Oxidized CaMKIIδ (oxCaMKIIδ) was downregulated at the end of reperfusion compared to before ischemia and losartan did not change these levels. Phosphorylation of CaMKIIδ mirrored the pattern of changes in oxCaMKIIδ levels. Losartan did not prevent the higher lipoperoxidation due to IR and did not influence NOX2 expression. Inhibition of CaMKII ameliorated cardiac IR injury; however, this was not accompanied with changes in the levels of either active form of CaMKIIδ in comparison to the angiotensin AT1 receptor blockade. In spite of no changes of oxCaMKIIδ, increased cardiac recovery of either therapy was abolished when combined together. This study showed that oxidative activation of CaMKIIδ is not elevated at the end of R phase. NOX2-oxCAMKIIδ signaling is unlikely to be involved in cardioprotective action of angiotensin AT1 receptor blockade which is partially abolished by concomitant CaMKII inhibition.
Collapse
Affiliation(s)
- Tomas Rajtik
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic
| | - Slavka Carnicka
- Institute for Heart Research, Slovak Academy of Sciences & Centre of Excellence, SAS NOREG, Bratislava, Slovak Republic
| | - Adrian Szobi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic
| | - Zoltan Giricz
- Cardiometabolic Research Group, Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Jin O-Uchi
- Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, USA
| | - Veronika Hassova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic
| | - Pavel Svec
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic
| | - Peter Ferdinandy
- Cardiometabolic Research Group, Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary; PharmaHungary Group, Szeged, Hungary
| | - Tanya Ravingerova
- Institute for Heart Research, Slovak Academy of Sciences & Centre of Excellence, SAS NOREG, Bratislava, Slovak Republic
| | - Adriana Adameova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Bratislava, Slovak Republic.
| |
Collapse
|
7
|
Xu JX, Si M, Zhang HR, Chen XJ, Zhang XD, Wang C, Du XN, Zhang HL. Phosphoinositide kinases play key roles in norepinephrine- and angiotensin II-induced increase in phosphatidylinositol 4,5-bisphosphate and modulation of cardiac function. J Biol Chem 2014; 289:6941-6948. [PMID: 24448808 DOI: 10.1074/jbc.m113.527952] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The seemly paradoxical Gq agonist-stimulated phosphoinositide production has long been known, but the underlying mechanism and its physiological significance are not known. In this study, we studied cardiac phosphoinositide levels in both cells and whole animals under the stimulation of norepinephrine (NE), angiotensin II (Ang II), and other physiologically relevant interventions. The results demonstrated that activation of membrane receptors related to NE or Ang II caused an initial increase and a later fall in phosphatidylinositol 4,5-bisphosphate (PIP2) levels in the primary cultured cardiomyocytes from adult rats. The possible mechanism underlying this increase in PIP2 was found to be through an enhanced activity of phosphatidylinositol 4-kinase IIIβ, which was mediated by an up-regulated interaction between phosphatidylinositol 4-kinase IIIβ and PKC; the increased activity of phosphatidylinositol 4-phosphate 5-kinase γ was also involved for NE-induced increase of PIP2. When the systolic functions of the NE/Ang II-treated cells were measured, a maintained or failed contractility was found to be correlated with a rise or fall in corresponding PIP2 levels. In two animal models of cardiac hypertrophy, PIP2 levels were significantly reduced in hypertrophic hearts induced by isoprenaline but not in those induced by swimming exercise. This study describes a novel mechanism for phosphoinositide metabolism and modulation of cardiac function.
Collapse
Affiliation(s)
- Jia-Xi Xu
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Man Si
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Hui-Ran Zhang
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Xing-Juan Chen
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Xi-Dong Zhang
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Chuan Wang
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Xiao-Na Du
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Hai-Lin Zhang
- Key Laboratory of Neural and Vascular Biology, Ministry of Education, the Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Province, and the Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050017, China.
| |
Collapse
|
8
|
Wu J, You J, Wang S, Zhang L, Gong H, Zou Y. Insights Into the Activation and Inhibition of Angiotensin II Type 1 Receptor in the Mechanically Loaded Heart. Circ J 2014; 78:1283-9. [DOI: 10.1253/circj.cj-14-0470] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jian Wu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| | - Jieyun You
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| | - Shijun Wang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| | - Li Zhang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| | - Hui Gong
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| | - Yunzeng Zou
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University
| |
Collapse
|
9
|
Dent MR, Tappia PS, Dhalla NS. Gender differences in β-adrenoceptor system in cardiac hypertrophy due to arteriovenous fistula. J Cell Physiol 2010; 226:181-6. [DOI: 10.1002/jcp.22321] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
10
|
Xu X, Zhao W, Wan W, Ji LL, Powers AS, Erikson JM, Zhang JQ. Exercise training combined with angiotensin II receptor blockade reduces oxidative stress after myocardial infarction in rats. Exp Physiol 2010; 95:1008-15. [PMID: 20660022 DOI: 10.1113/expphysiol.2010.054221] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An increase in oxidative stress and decrease in antioxidant enzymes have been suggested to be involved in the pathophysiology of myocardial infarction (MI). In this study in rats, treadmill exercise training and losartan treatment began 1 week post-myocardial infarction (MI) and lasted 8 weeks. We evaluated the changes in the mRNA and protein expressions for the enzymatic antioxidants superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase after exercise and losartan treatment post-MI. Our results demonstrated that GPx and catalase mRNA levels were comparable among all the groups, while the mRNA level for manganese SOD (MnSOD) was significantly increased in exercise training with/without losartan treatment compared with the sedentary post-MI group. Moreover, the mRNA level for gp91(phox) was dramatically decreased by a combination of exercise and losartan treatment. The protein levels for MnSOD were significantly elevated by exercise training in combination with losartan treatment. The protein levels for catalase were significantly increased in response to exercise, and further augmented by exercise together with losartan treatment. Thiobarbituric acid-reactive substances in plasma were significantly increased in the post-MI rats, but were decreased by exercise or losartan treatment, indicating that both exercise and losartan may reduce lipid oxidative damage. In addition, catalase and SOD enzymatic activities were significantly enhanced by exercise combined with losartan treatment. Our results suggest that exercise training improves catalase and MnSOD expression and attenuates oxidative stress. These effects are potentiated when combining exercise with angiotensin II receptor blockade.
Collapse
Affiliation(s)
- Xiaohua Xu
- Laboratory of Cardiovascular Research, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Phospholipase Cbeta4 isozyme is expressed in human, rat, and murine heart left ventricles and in HL-1 cardiomyocytes. Mol Cell Biochem 2009; 337:167-73. [PMID: 19856080 DOI: 10.1007/s11010-009-0296-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 10/08/2009] [Indexed: 01/19/2023]
Abstract
Phospholipase C-beta (PLCbeta) isozymes (PLCbeta(1) and PLCbeta(3)) have been extensively characterized in cardiac tissue, but no data are available for the PLCbeta(4) isozyme. In this study, PLCbeta((1-4)) isozymes mRNA relative expression was studied by real-time PCR (RT-PCR) in human, rat, and murine left ventricle and the presence of PLCbeta(4) isozyme at the protein level was confirmed by Western blotting in all species studied. Confocal microscopy experiments carried out in HL-1 cardiomyocytes revealed a sarcoplasmic subcellular distribution of PLCbeta(4). Although there were unexpected significant interspecies differences in the PLCbeta((1-4)) mRNA expression, PLCbeta(4) mRNA was the main transcript expressed in all left ventricles studied. Thus, whereas in human and rat left ventricles PLCbeta(4) > PLCbeta(3) > PLCbeta(2) > PLCbeta(1) mRNA pattern of expression was found, in murine left ventricle the pattern of expression was different, i.e., PLCbeta(4) > PLCbeta(1) > PLCbeta(3) > PLCbeta(2). However, results obtained in mouse HL-1 cardiomyocytes showed PLCbeta(3) approximately PLCbeta(4) > PLCbeta(1) > PLCbeta(2) pattern of mRNA expression indicating a probable cell type specific expression of the different PLCbeta isozymes in cardiomyocytes. Finally, RT-PCR experiments showed a trend, even though not significant (P = 0.067), to increase PLCbeta(4) mRNA levels in HL-1 cardiomyocytes after angiotensin II treatment. These results demonstrate the presence of PLCbeta(4) in the heart and in HL-1 cardiomyocytes showing a different species-dependent pattern of expression of the PLCbeta((1-4)) transcripts. We discuss the relevance of these findings in relation to the development of cardiac hypertrophy.
Collapse
|
12
|
Singal T, Dhalla NS, Tappia PS. Reciprocal regulation of transcription factors and PLC isozyme gene expression in adult cardiomyocytes. J Cell Mol Med 2009; 14:1824-35. [PMID: 19538471 PMCID: PMC3829042 DOI: 10.1111/j.1582-4934.2009.00812.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
By employing a pharmacological approach, we have shown that phospholipase C (PLC) activity is involved in the regulation of gene expression of transcription factors such as c-Fos and c-Jun in cardiomyocytes in response to norepinephrine (NE). However, there is no information available regarding the identity of specific PLC isozymes involved in the regulation of c-Fos and c-Jun or on the involvement of these transcription factors in PLC isozyme gene expression in adult cardiomyocytes. In this study, transfection of cardiomyocytes with PLC isozyme specific siRNA was found to prevent the NE-mediated increases in the corresponding PLC isozyme gene expression, protein content and activity. Unlike PLC gamma(1) gene, silencing of PLC beta(1), beta(3) and delta(1) genes with si RNA prevented the increases in c-Fos and c-Jun gene expression in response to NE. On the other hand, transfection with c-Jun si RNA suppressed the NE-induced increase in c-Jun as well as PLC beta(1), beta(3) and delta(1) gene expression, but had no effect on PLC gamma(1) gene expression. Although transfection of cardiomyocytes with c-Fos si RNA prevented NE-induced expression of c-Fos, PLC beta(1) and PLC beta(3) genes, it did not affect the increases in PLC delta(1) and PLC gamma(1) gene expression. Silencing of either c-Fos or c-Jun also depressed the NE-mediated increases in PLC beta(1), beta(3) and gamma(1) protein content and activity in an isozyme specific manner. Furthermore, silencing of all PLC isozymes as well as of c-Fos and c-Jun resulted in prevention of the NE-mediated increase in atrial natriuretic factor gene expression. These findings, by employing gene silencing techniques, demonstrate that there occurs a reciprocal regulation of transcription factors and specific PLC isozyme gene expression in cardiomyocytes.
Collapse
Affiliation(s)
- Tushi Singal
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre & Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | | | |
Collapse
|
13
|
Singal T, Dhalla NS, Tappia PS. Regulation of c-Fos and c-Jun gene expression by phospholipase C activity in adult cardiomyocytes. Mol Cell Biochem 2009; 327:229-39. [PMID: 19225867 DOI: 10.1007/s11010-009-0061-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Accepted: 02/04/2009] [Indexed: 11/28/2022]
Abstract
This study was undertaken to determine whether gene expression for transcriptional factors such as c-Fos and c-Jun is regulated by phospholipase C (PLC) activity. Norepinephrine (NE) increased PLC beta(1), beta(3), gamma(1), and delta(1) isozyme gene expression, protein contents and their activities in adult rat cardiomyocytes. Increases in PLC beta(1), beta(3), gamma(1), and delta(1) activities and gene expression in response to NE were prevented by prazosin, an alpha(1)-adrenoceptor (AR) antagonist. Furthermore, mRNA levels for c-Fos and c-Jun, unlike other transcriptional factors, were increased by both NE and phenylephrine, a specific alpha(1)-AR agonist. Increases in c-Fos and c-Jun gene expression due to NE were attenuated by both prazosin and a PLC inhibitor, U73122. Activation of protein kinase C (PKC) with phorbol myristate acetate increased c-Fos and c-Jun mRNA, whereas inhibition of PKC with bisindolylmaleimide as well as inhibition of extracellular signal-regulated kinases (ERK) 1/2 with PD98059 abolished the NE-induced increase in c-Fos and c-Jun gene expression. Reduction of c-Jun phosphorylation by SP600125, an inhibitor of JNK activity, was associated with an attenuation of the NE-induced increases in PLC gene expression. It is suggested that c-Fos and c-Jun gene expression is regulated by PLC in adult cardiomyocytes through a PKC- and ERK1/2-dependent pathway.
Collapse
Affiliation(s)
- Tushi Singal
- Department of Physiology, Faculty of Medicine, Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, University of Manitoba, Winnipeg, Canada
| | | | | |
Collapse
|
14
|
|
15
|
Bian Z, Cai J, Shen DF, Chen L, Yan L, Tang Q, Li H. Cellular repressor of E1A-stimulated genes attenuates cardiac hypertrophy and fibrosis. J Cell Mol Med 2008; 13:1302-13. [PMID: 19413895 PMCID: PMC4496144 DOI: 10.1111/j.1582-4934.2008.00633.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cellular repressor of E1A-stimulated genes (CREG) is a secreted glycoprotein of 220 amino acids. It has been proposed that CREG acts as a ligand that enhances differentiation and/or reduces cell proliferation. CREG has been shown previously to attenuate cardiac hypertrophy in vitro. However, such a role has not been determined in vivo. In the present study, we tested the hypothesis that overexpression of CREG in the murine heart would protect against cardiac hypertrophy and fibrosis in vivo. The effects of constitutive human CREG expression on cardiac hypertrophy were investigated using both in vitro and in vivo models. Cardiac hypertrophy was produced by aortic banding and infusion of angiotensin II in CREG transgenic mice and control animals. The extent of cardiac hypertrophy was quantitated by two-dimensional and M-mode echocardiography as well as by molecular and pathological analyses of heart samples. Constitutive over-expression of human CREG in the murine heart attenuated the hypertrophic response, markedly reduced inflammation. Cardiac function was also preserved in hearts with increased CREG levels in response to hypertrophic stimuli. These beneficial effects were associated with attenuation of the mitogen-activated protein kinase (MAPK)-extracellular signal-regulated kinase 1 (MEK-ERK1)/2-dependent signalling cascade. In addition, CREG expression blocked fibrosis and collagen synthesis through blocking MEK-ERK1/2-dependent Smad 2/3 activation in vitro and in vivo. Therefore, the expression of CREG improves cardiac functions and inhibits cardiac hypertrophy, inflammation and fibrosis through blocking MEK-ERK1/2-dependent signalling.
Collapse
Affiliation(s)
- Zhouyan Bian
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | | | | | | | | | | | | |
Collapse
|
16
|
Dhalla NS, Saini-Chohan HK, Rodriguez-Leyva D, Elimban V, Dent MR, Tappia PS. Subcellular remodelling may induce cardiac dysfunction in congestive heart failure. Cardiovasc Res 2008; 81:429-38. [DOI: 10.1093/cvr/cvn281] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
17
|
Abstract
Cardiac hypertrophy, congestive heart failure, diabetic cardiomyopathy and myocardial ischemia-reperfusion injury are associated with a disturbance in cardiac sarcolemmal membrane phospholipid homeostasis. The contribution of the different phospholipases and their related signaling mechanisms to altered function of the diseased myocardium is not completely understood. Resolution of this issue is essential for both the understanding of the pathophysiology of heart disease and for determining if components of the phospholipid signaling pathways could serve as appropriate therapeutic targets. This review provides an outline of the role of phospholipase A2, C and D and subsequent signal transduction mechanisms in different cardiac pathologies with a discussion of their potential as targets for drug development for the prevention/treatment of heart disease.
Collapse
Affiliation(s)
- Paramjit S Tappia
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre & Departments of Human Anatomy & Cell Science, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | |
Collapse
|
18
|
Tappia PS. Phospholipid-mediated signaling systems as novel targets for treatment of heart disease. Can J Physiol Pharmacol 2007; 85:25-41. [PMID: 17487243 DOI: 10.1139/y06-098] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The phospholipases associated with the cardiac sarcolemmal (SL) membrane hydrolyze specific membrane phospholipids to generate important lipid signaling molecules, which are known to influence normal cardiac function. However, impairment of the phospholipases and their related signaling events may be contributory factors in altering cardiac function of the diseased myocardium. The identification of the changes in such signaling systems as well as understanding the contribution of phospholipid-signaling pathways to the pathophysiology of heart disease are rapidly emerging areas of research in this field. In this paper, I provide an overview of the role of phospholipid-mediated signal transduction processes in cardiac hypertrophy and congestive heart failure, diabetic cardiomyopathy, as well as in ischemia-reperfusion. From the cumulative evidence presented, it is suggested that phospholipid-mediated signal transduction processes could serve as novel targets for the treatment of the different types of heart disease.
Collapse
Affiliation(s)
- Paramjit S Tappia
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre and Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, R2H 2A6, Canada
| |
Collapse
|
19
|
Rodent models of heart failure. J Pharmacol Toxicol Methods 2007; 56:1-10. [PMID: 17391988 DOI: 10.1016/j.vascn.2007.01.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 01/31/2007] [Indexed: 11/28/2022]
Abstract
Heart failure, a complex disorder with heterogeneous aetiologies remains one of the most threatening diseases known. It is a clinical syndrome attributable to a multitude of factors that begins with the compensatory response known as hypertrophy, followed by a decompensated state that finally results in heart failure. Given the lack of a unified theory of heart failure, future research efforts are required to unify and synthesize our current understanding of the multiple mechanisms that control remodelling in heart under various stress conditions. During the past few decades, use of animal models has provided new insights into the complex pathogenesis of this syndrome. Rodents have contributed significantly in the understanding of the pathogenesis and progression of heart failure. With the advent of the transgenic era, rodent models have revolutionized preclinical research associated with heart failure. These models combined with physiological measurements of cardiac hemodynamics, are expected to yield more valuable information regarding the molecular mechanisms of heart failure and aid in the discovery of novel therapeutic targets. However, all animal models used have advantages and limitations, and the issues determining transfer from preclinical to clinical require critical evaluation. The present review focuses upon rodent models of heart failure.
Collapse
|
20
|
Tappia PS, Singal T, Dent MR, Asemu G, Mangat R, Dhalla NS. Phospholipid-mediated signaling in diseased myocardium. ACTA ACUST UNITED AC 2006. [DOI: 10.2217/17460875.1.6.701] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|