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Molecular Mechanism of HSF1-Upregulated ALDH2 by PKC in Ameliorating Pressure Overload-Induced Heart Failure in Mice. BIOMED RESEARCH INTERNATIONAL 2020; 2020:3481623. [PMID: 32626739 PMCID: PMC7313111 DOI: 10.1155/2020/3481623] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/09/2020] [Indexed: 11/18/2022]
Abstract
Evidences abound that HSF1 and ALDH2 are of cardioprotective effect, yet there is still no report on whether HSF1 can regulate ALDH2 to delay the occurrence of heart failure. We first established the pressure overload-induced heart failure model of mice by transverse aortic constriction (TAC) and discovered that, in the forming period of heart failure, changes of HSF1 and ALDH2 expression recorded the consistent trend. When HSF1 was upregulated/downregulated to delay/promote the occurrence of heart failure, PKC and ALDH2 also showed increased/decreased expression. And when ALDH2 was upregulated/downregulated, the role of HSF1 in delaying the occurrence of heart failure strengthened/weakened. Next, we used mechanical stretch to establish a pressure-stimulated myocardial hypertrophy model and discovered an increased expression of both HSF1 and ALDH2. When HSF1 was upregulated/downregulated to increase/decrease the expression of myocardial hypertrophy gene beta-MHC, PKC and ALDH2 recorded an increased/decreased expression. When an inhibitor was used to downregulate the expression of PKC in cardiomyocytes, we found that the role of HSF1 in upregulating ALDH2 beta-MHC weakened. These findings suggest that HSF1 can upregulate the expression of ALDH2 via PKC to promote pressure-stimulated myocardial compensatory hypertrophy, which is an important molecular pathway for HSF1 to ameliorate heart failure.
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2
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Abstract
It has been recognized that myocardial apoptosis is one major factor in the development of heart dysfunction and autophagy has been shown to influence the apoptosis. In previous studies, we reported that anti-β1-adrenergic receptor autoantibodies (β1-AABs) decreased myocardial autophagy, but the role of decreased autophagy in cardiomyocyte apoptosis remains unclear. In the present study, we used a β1-AAB-immunized rat model to investigate the role of decreased autophagy in cardiomyocyte apoptosis. We reported that the level of autophagic flux increased early and then decreased in an actively β1-AAB-immunized rat model. Rapamycin, an mTOR inhibitor, restored myocardial apoptosis in the presence of β1-AABs. Further, we found that the early increase of autophagy was an adaptive stress response that is possibly unrelated to β1-AR, and the activation of the β1-AR and PKA contributed to late decreased autophagy. Then, after upregulating or inhibiting autophagy with rapamycin, Atg5 overexpression adenovirus or 3-methyladenine in cultured primary neonatal rat cardiomyocytes, we found that autophagy decline promoted myocardial apoptosis effectively through the mitochondrial apoptotic pathway. In conclusion, the reduction of apoptosis through the proper regulation of autophagy may be important for treating patients with β1-AAB-positive heart dysfunction.
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Bae H, Choi J, Kim YW, Lee D, Kim JH, Ko JH, Bang H, Kim T, Lim I. Effects of Nitric Oxide on Voltage-Gated K⁺ Currents in Human Cardiac Fibroblasts through the Protein Kinase G and Protein Kinase A Pathways but Not through S-Nitrosylation. Int J Mol Sci 2018. [PMID: 29534509 PMCID: PMC5877675 DOI: 10.3390/ijms19030814] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
This study investigated the expression of voltage-gated K+ (KV) channels in human cardiac fibroblasts (HCFs), and the effect of nitric oxide (NO) on the KV currents, and the underlying phosphorylation mechanisms. In reverse transcription polymerase chain reaction, two types of KV channels were detected in HCFs: delayed rectifier K+ channel and transient outward K+ channel. In whole-cell patch-clamp technique, delayed rectifier K+ current (IK) exhibited fast activation and slow inactivation, while transient outward K+ current (Ito) showed fast activation and inactivation kinetics. Both currents were blocked by 4-aminopyridine. An NO donor, S-nitroso-N-acetylpenicillamine (SNAP), increased the amplitude of IK in a concentration-dependent manner with an EC50 value of 26.4 µM, but did not affect Ito. The stimulating effect of SNAP on IK was blocked by pretreatment with 1H-(1,2,4)oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or by KT5823. 8-bromo-cyclic GMP stimulated the IK. The stimulating effect of SNAP on IK was also blocked by pretreatment with KT5720 or by SQ22536. Forskolin and 8-bromo-cyclic AMP each stimulated IK. On the other hand, the stimulating effect of SNAP on IK was not blocked by pretreatment of N-ethylmaleimide or by DL-dithiothreitol. Our data suggest that NO enhances IK, but not Ito, among KV currents of HCFs, and the stimulating effect of NO on IK is through the PKG and PKA pathways, not through S-nitrosylation.
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Affiliation(s)
- Hyemi Bae
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Jeongyoon Choi
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Young-Won Kim
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Donghee Lee
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Jung-Ha Kim
- Department of Family Medicine, College of Medicine, Chung-Ang University Hospital, 102 Heukseok-ro, Seoul 06973, Korea.
| | - Jae-Hong Ko
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Hyoweon Bang
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
| | - Taeho Kim
- Department of Internal Medicine, College of Medicine, Chung-Ang University Hospital, 102 Heukseok-ro, Seoul 06973, Korea.
| | - Inja Lim
- Department of Physiology, College of Medicine, Chung-Ang University, 84 Heukseok-ro, Seoul 06974, Korea.
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Cai Z, Shi T, Zhuang R, Fang H, Jiang X, Shao Y, Zhou H. Protective effect of N-acetylcysteine activated carbon release microcapsule on myocardial ischemia-reperfusion injury in rats. Exp Ther Med 2017; 15:1809-1818. [PMID: 29434769 PMCID: PMC5776512 DOI: 10.3892/etm.2017.5653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 05/05/2017] [Indexed: 12/21/2022] Open
Abstract
With the development of science and technology, and development of artery bypass, methods such as cardiopulmonary cerebral resuscitation have been practiced in recent years. Despite this, some methods fail to promote or recover the function of tissues and organs, and in some cases, may aggravate dysfunction and structural damage to tissues. The latter is typical of ischemia-reperfusion (IR) injury. Lipid peroxidation mediated by free radicals is an important process of myocardial IR injury. Myocardial IR has been demonstrated to induce the formation of large numbers of free radicals in rats, which promotes the peroxidation of lipids within unsaturated fatty acids in the myocardial cell membrane. Markers of lipid peroxidation include malondialdehyde, superoxide dismutase and lactic dehydrogenase. Recent studies have demonstrated that N-acetylcysteine (NAC) is able to dilate blood vessels, prevent oxidative damage, improve immunity, inhibit apoptosis and the inflammatory response and promote glutathione synthesis in cells. NAC also improves the systolic function of myocardial cells and cardiac function, prevents myocardial apoptosis, protects ventricular remodeling and vascular remodeling, reduces opiomelanocortin levels in the serum and increases the content of nitric oxide in the serum, thus improving vascular endothelial function. Therefore, NAC has potent pharmacological activity; however, the relatively fast metabolism of NAC, along with its large clinical dose and low bioavailability, limit its applications. The present study combined NAC with medicinal activated carbons, and prepared N-acetylcysteine activated carbon sustained-release microcapsules (ACNACs) to overcome the limitations of NAC. It was demonstrated that ACNACs exerted greater effective protective effects than NAC alone on myocardial IR injury in rats.
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Affiliation(s)
- Zhaobin Cai
- Department of Cardiology, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Tingting Shi
- Department of Pharmaceutical Preparation, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Rangxiao Zhuang
- Department of Pharmaceutical Preparation, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Hongying Fang
- Department of Pharmaceutical Preparation, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Xiaojie Jiang
- Department of Pharmaceutical Preparation, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Yidan Shao
- Department of Pharmaceutical Preparation, The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310023, P.R. China
| | - Hongping Zhou
- Department of Pharmacy, Hangzhou Children's Hospital, Hangzhou, Zhejiang 310014, P.R. China
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5
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Bae H, Lim I. Effects of nitric oxide on large-conductance Ca 2+ -activated K + currents in human cardiac fibroblasts through PKA and PKG-related pathways. Clin Exp Pharmacol Physiol 2017; 44:1116-1124. [PMID: 28731589 DOI: 10.1111/1440-1681.12817] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/29/2017] [Accepted: 07/11/2017] [Indexed: 01/22/2023]
Abstract
The human cardiac fibroblast (HCF) is the most abundant cell type in the myocardium, and HCFs play critical roles in maintaining normal cardiac function. However, unlike cardiomyocytes, the electrophysiology of HCFs is not well established. In the cardiovascular system, Ca2+ -activated K+ (KCa) channels have distinct physiological and pathological functions, and nitric oxide (NO) plays a key role. In this study, we investigated the potential effects of NO on KCa channels in HCFs. We recorded strong oscillating, well-maintained outward K+ currents without marked inactivation throughout the test pulse period and detected outward rectification in the I-V curve; these are all characteristics that are typical of KCa currents. These currents were blocked with iberiotoxin (IBTX, a BKCa blocker) but not with TRAM-34 (an IKCa blocker). The amplitudes of the currents were increased with SNAP (an NO donor), and these increases were inhibited with IBTX. The SNAP-stimulating effect on the BKCa currents was blocked by pretreatment with KT5823 (a protein kinase G [PKG] inhibitor) or 1 H-[1,-2, -4] oxadiazolo-[4,-3-a] quinoxalin-1-one (ODQ; a soluble guanylate cyclase inhibitor). Additionally, 8-bromo-cyclic guanosine 3',5'-monophosphate (8-Br-cGMP) stimulated the BKCa currents, and pretreatment with KT5720 (a protein kinase A [PKA] inhibitor) and SQ22536 (an adenylyl cyclase inhibitor) blocked the NO-stimulating effect on the BKCa currents. Furthermore, 8-bromo-cyclic adenosine 3',5'-monophosphate (8-Br-cAMP) activated the BKCa currents. These data suggest that BKCa current is the main subtype of the KCa current in HCFs and that NO enhances these currents through the PKG and PKA pathways.
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Affiliation(s)
- Hyemi Bae
- Department of Physiology, College of Medicine, Chung-Ang University, Seoul, Korea
| | - Inja Lim
- Department of Physiology, College of Medicine, Chung-Ang University, Seoul, Korea
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Sardu C, Marfella R, Santulli G, Paolisso G. Functional role of miRNA in cardiac resynchronization therapy. Pharmacogenomics 2015; 15:1159-68. [PMID: 25084208 DOI: 10.2217/pgs.14.76] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Heart failure (HF) disease progression is related to numerous adaptive processes including cardiac fibrosis, hypertrophy and apoptosis by activation of the 'fetal' gene program and downregulation of mRNA signatures, suggesting the importance of molecular mechanisms that suppress mRNA steady-state levels. miRNAs (miRs) are small, noncoding RNAs that bind mRNAs at their 3'-UTRs, leading to mRNA degradation or inhibition of protein translation. Several miRs are unregulated in response to cellular stress and can modify cellular functions such as proliferation, differentiation and programmed death; these miRs are also regulated in cardiac disease. Cardiac resynchronization therapy improves cardiac performance and myocardial mechanical efficiency. In this updated critical appraisal we report on the main miRs that play a key role in response to cardiac resynchronization therapy (i.e., responder vs nonresponder HF patients), focusing on the miR-mediated modulation of cardiac angiogenesis, apoptosis, fibrosis and membrane ionic currents.
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Affiliation(s)
- Celestino Sardu
- Department of Medical, Surgical, Neurological, Metabolic & Geriatric Sciences, Second University of Naples, Piazza Miraglia, 2, 80138, Naples, Italy
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A P2X7 receptor antagonist attenuates experimental autoimmune myocarditis via suppressed myocardial CD4+ T and macrophage infiltration and NADPH oxidase 2/4 expression in mice. Heart Vessels 2014; 30:527-33. [PMID: 24879505 DOI: 10.1007/s00380-014-0527-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 05/16/2014] [Indexed: 02/03/2023]
Abstract
Myocarditis is a clinically serious disease; however, no effective treatment has been elucidated. The P2X7 receptor is related to the pathophysiology of inflammation in many cardiovascular diseases. The P2X7 receptor antagonist is promising as an immunosuppressive treatment; however, its role in myocarditis is still to be established. To clarify the role of the P2X7 receptor, we used a murine experimental autoimmune myocarditis (EAM) model. Mice were immunized on day 0 and 7 with synthetic cardiac myosin peptide to establish EAM. The mice with induced EAM were treated with A740003, the P2X7 receptor antagonist (n = 10), or not treated (n = 11); hearts were harvested on day 21. The P2X7 receptor antagonist improved myocardial contraction of the EAM hearts via suppressed infiltration of CD4+ T cells and macrophages. Similarly, mRNA expression of interleukin 1 beta, the P2X7 receptor and NADPH oxidase 2/4 was lower in the heart of the P2X7 receptor antagonist-treated group compared to the non-treat group. The P2X7 receptor antagonist suppressed EAM development; thus, this inhibition is promising for treating clinical myocarditis.
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Harr MW, Distelhorst CW. Apoptosis and autophagy: decoding calcium signals that mediate life or death. Cold Spring Harb Perspect Biol 2010; 2:a005579. [PMID: 20826549 DOI: 10.1101/cshperspect.a005579] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Calcium is a versatile and dynamic 2nd messenger that is essential for the survival of all higher organisms. In cells that undergo activation or excitation, calcium is released from the endoplasmic/sarcoplasmic reticulum to activate calcium-dependent kinases and phosphatases, thereby regulating numerous cellular processes; for example, apoptosis and autophagy. In the case of apoptosis, endogenous ligands or pharmacological agents induce prolonged cytosolic calcium elevation, which in turn leads to cell death. In contrast, there is now evidence that calcium regulates autophagy by several mechanisms, and these may be important for maintaining cell survival. Here we summarize what is known about how calcium regulates these life and death decisions. We pay particular attention to pathways that have been described in lymphocytes and cardiomyocytes, as these systems provide optimal models for understanding calcium signaling in the context of normal cell physiology.
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Affiliation(s)
- Michael W Harr
- Division of Hematology and Oncology, Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Singh M, Roginskaya M, Dalal S, Menon B, Kaverina E, Boluyt MO, Singh K. Extracellular ubiquitin inhibits beta-AR-stimulated apoptosis in cardiac myocytes: role of GSK-3beta and mitochondrial pathways. Cardiovasc Res 2009; 86:20-8. [PMID: 20015977 DOI: 10.1093/cvr/cvp402] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS Beta-adrenergic receptor (beta-AR) stimulation induces apoptosis in adult rat ventricular myocytes (ARVMs) via the activation of glycogen synthase kinase-3beta (GSK-3beta) and mitochondrial pathways. However, beta-AR stimulation induces apoptosis only in a fraction ( approximately 15-20%) of ARVMs. We hypothesized that ARVMs may secrete/release a survival factor(s) which protects 80-85% of cells from apoptosis. METHODS AND RESULTS Using two-dimensional gel electrophoresis followed by MALDI TOF and MS/MS, we identified ubiquitin (Ub) in the conditioned media of ARVMs treated with beta-AR agonist (isoproterenol). Western blot analysis confirmed increased Ub levels in the conditioned media 3 and 6 h after beta-AR stimulation. Inhibition of beta1-AR and beta2-AR subtypes inhibited beta-AR-stimulated increases in extracellular levels of Ub, whereas activation of adenylyl cyclase using forskolin mimicked the effects of beta-AR stimulation. Incubation of cells with exogenous biotinylated Ub followed by western blot analysis of the cell lysates showed uptake of extracellular Ub into cells, which was found to be higher after beta-AR stimulation (1.9 +/- 0.4-fold; P < 0.05 vs. control, n = 6). Pre-treatment with Ub inhibited beta-AR-stimulated increases in apoptosis. Inhibition of phosphoinositide 3-kinase using wortmannin and LY-294002 prevented anti-apoptotic effects of extracellular Ub. Ub pre-treatment inhibited beta-AR-stimulated activation of GSK-3beta and c-Jun N-terminal kinase (JNK) and increases in the levels of cytosolic cytochrome c. The use of methylated Ub suggested that the anti-apoptotic effects of extracellular Ub are mediated via monoubiquitination. CONCLUSION beta-AR stimulation increases levels of Ub in the conditioned media. Extracellular Ub plays a protective role in beta-AR-stimulated apoptosis, possibly via the inactivation of GSK-3beta/JNK and mitochondrial pathways.
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Affiliation(s)
- Mahipal Singh
- Department of Physiology, James H Quillen College of Medicine, James H Quillen Veterans Affairs Medical Center, East Tennessee State University, PO Box 70576, Johnson City, TN 37614, USA
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10
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MAPK signalling in skeletal muscle-derived stem cells after daunorubicin treatment. ACTA ACUST UNITED AC 2009. [DOI: 10.2478/v10054-008-0045-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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Liao S, Porter D, Scott A, Newman G, Doetschman T, Schultz JEJ. The cardioprotective effect of the low molecular weight isoform of fibroblast growth factor-2: the role of JNK signaling. J Mol Cell Cardiol 2006; 42:106-20. [PMID: 17150229 PMCID: PMC1852491 DOI: 10.1016/j.yjmcc.2006.10.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 09/22/2006] [Accepted: 10/13/2006] [Indexed: 02/02/2023]
Abstract
UNLABELLED Our laboratory showed that overexpression of fibroblast growth factor-2 (FGF2) protected the heart against ischemia-reperfusion injury. FGF2 has different protein isoforms (low [LMW] and high [HMW] molecular weight isoforms) produced from alternative translation start sites. However, which FGF2 isoform(s) mediates this cardioprotection, and which signaling pathway (i.e., mitogen-activated protein kinase (MAPK)) elicits FGF2 isoform-induced cardioprotection remains to be elucidated. METHODS AND RESULTS Wildtype, Fgf2 KO (absence of all FGF2 isoforms) and FGF2 LMWKO (absence of LMW isoform) hearts were subjected to an ex vivo work-performing heart ischemic model of 60 min ischemia and 120 min reperfusion. There was a significant decrease in the recovery of post-ischemic contractile function (p<0.05) in Fgf2 KO and FGF2 LMWKO mouse hearts compared to wildtype hearts. Following ischemia-reperfusion injury, MKK4/7, JNK, and c-Jun were significantly phosphorylated (i.e., activated), and the levels of TUNEL-positive nuclei and caspase 3 cleavage were significantly increased in vehicle-treated Fgf2 KO and FGF2 LMWKO compared to wildtype hearts (p<0.05). A novel JNK pathway inhibitor, CEP11004 (50 nM), significantly restored the post-ischemic contractile function and reduced myocardial cell death, as measured by CK release and apoptotic markers, compared to DMSO-treated cohorts (p<0.05). Overall, our data indicate that the LMW isoform has an important role in restoring cardiac function after ischemia-reperfusion (I/R) injury. These results provide unequivocal evidence that inhibition of JNK signaling is involved in FGF2 LMW isoform-mediated cardioprotection and that the potential mechanism may be through inhibition of the apoptotic process.
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Affiliation(s)
- Siyun Liao
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267
| | - Darius Porter
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267
| | - Alana Scott
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267
| | - Gilbert Newman
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267
| | - Thomas Doetschman
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267
| | - Jo El J. Schultz
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267
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Abstract
Zinc plays a vital role in various cellular functions. Zinc deprivation is associated with severe disorders related to growth, maturation, and stress responses. In the heart, zinc affects differentiation and regeneration of cardiac muscle, cardiac conductance, acute stress responses, and recovery of heart transplants. Recent discoveries of the molecular players in zinc homeostasis revealed that the amount of intracellular free zinc is tightly controlled on the level of uptake, intracellular sequestration, redistribution, storage, and elimination, consequently creating a narrow window of optimal zinc concentration in the cells. Most of intracellular zinc is bound to numerous structural and regulatory proteins, with metabolically active, labile zinc present in picoto nanomolar concentrations. The central position of zinc in the redox signaling network is built on its unique chemical nature. The redox inert zinc creates a redox active environment when it binds to a sulfur ligand. The reversible oxidation of the sulfur ligand is coupled to the reversible zinc release from the protein, thereby executing the task of so-called protein "redox zinc switch." Clearly, the impairment of zinc homeostasis will have far reaching physiological consequences.
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Affiliation(s)
- Irina Korichneva
- Department of Medicine, Division of Cardiovascular Diseases and Hypertension, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903, USA.
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14
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Gao Y, Liu HR, Zhao RR, Zhi JM. Autoantibody against cardiac beta1-adrenoceptor induces apoptosis in cultured neonatal rat cardiomyocytes. Acta Biochim Biophys Sin (Shanghai) 2006; 38:443-9. [PMID: 16820859 DOI: 10.1111/j.1745-7270.2006.00185.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
To clarify whether apoptosis is involved in the injury processes induced by autoantibody against cardiac beta1-adrenoceptor, we investigated the biological and apoptotic effects of antibodies on cultured neonatal rat cardiomyocytes. Wistar rats were immunized with peptides corresponding to the second extracellular loop of the beta1-adrenoceptor to induce the production of anti-beta1-adrenoceptor antibodies in the sera. Immunoglobulin (Ig) G in the sera was detected using synthetic antigen enzyme-linked immunosorbent assay and purified using the diethylaminoethyl cellulose ion exchange technique. Apoptosis of cardiomyocytes was evaluated using agarose gel electrophoresis and flow cytometry. Our results showed that the positive serum IgG greatly increased the beating rates of cardiomyocytes and showed an agonist-like activity. Furthermore, positive serum IgG induced cardiomyocyte apoptosis after treatment with beta1-adrenoceptor overstimulation for 48 h. The effects of monoclonal antibody against beta1-adrenoceptor were also found to be similar to those of positive serum IgG. It was suggested that the autoantibody could induce cardiomyocyte apoptosis by excessive stimulation of beta1-adrenoceptor.
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MESH Headings
- Animals
- Animals, Newborn
- Apoptosis
- Autoantibodies/immunology
- Cells, Cultured
- DNA Fragmentation
- Flow Cytometry
- Heart Rate/drug effects
- Humans
- Immunoglobulin G/pharmacology
- Isoproterenol/pharmacology
- Models, Cardiovascular
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/immunology
- Peptides/chemistry
- Peptides/immunology
- Protein Structure, Tertiary
- Rats
- Rats, Wistar
- Receptors, Adrenergic, beta-1/chemistry
- Receptors, Adrenergic, beta-1/immunology
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Affiliation(s)
- Yan Gao
- Department of Cardiovascular Physiology, Shanxi Medical University, Taiyuan 030001, China
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15
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Menon B, Krishnamurthy P, Kaverina E, Johnson JN, Ross RS, Singh M, Singh K. Expression of the cytoplasmic domain of β1 integrin induces apoptosis in adult rat ventricular myocytes (ARVM) via the involvement of caspase-8 and mitochondrial death pathway. Basic Res Cardiol 2006; 101:485-93. [PMID: 16783488 DOI: 10.1007/s00395-006-0602-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Revised: 04/05/2006] [Accepted: 05/10/2006] [Indexed: 10/24/2022]
Abstract
Stimulation of beta-adrenergic receptor (beta-AR) induces cardiac myocyte apoptosis. Integrins, a family of cell-surface receptors, play an important role in the regulation of cardiac myocyte apoptosis and ventricular remodeling. Cleavage of extracellular domain of beta1 integrin, also called integrin shedding, is observed during cardiac hypertrophy and progression to early heart failure. Here we show that stimulation of beta-AR induces beta1 integrin fragmentation in mouse heart. To examine the role of intracellular domain of beta1 integrin in cardiac myocyte apoptosis, a chimeric receptor consisting of the cytoplasmic tail domain of beta(1A) integrin and the extracellular/transmembrane domain of the interleukin-2 receptor (TAC-beta1) was expressed in adult rat ventricular myocytes (ARVM) using adenoviruses. TAC-beta1 increased the percentage of apoptotic ARVM as measured by TUNEL-staining assay. TAC-beta1-induced apoptosis was found to be associated with increased cytosolic cytochrome c and decreased mitochondrial membrane potential. TAC-beta1 increased caspase-8 activity. Z-IETD-FMK, a specific caspase-8 inhibitor, significantly inhibited TAC-beta1-induced apoptosis. TAC-beta1 expression also increased cleavage of Bid, a pro-apoptotic Bcl-2 family protein. These data suggest that shedding of beta1 integrin may be a mechanism of induction of apoptosis during beta-AR-stimulated cardiac remodeling.
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MESH Headings
- Animals
- Apoptosis/physiology
- BH3 Interacting Domain Death Agonist Protein/metabolism
- Caspase 8/metabolism
- Cells, Cultured
- Cytochromes c/metabolism
- Integrin beta1/genetics
- Integrin beta1/physiology
- Male
- Membrane Potential, Mitochondrial/physiology
- Mice
- Mitochondria, Heart/physiology
- Myocytes, Cardiac/pathology
- Myocytes, Cardiac/physiology
- Protein Structure, Tertiary/genetics
- Protein Structure, Tertiary/physiology
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, beta/physiology
- Receptors, Interleukin-2/physiology
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Affiliation(s)
- Bindu Menon
- Department of Physiology, James H Quillen College of Medicine, James H Quillen Veterans Affairs Medical Center, East Tennessee State University, PO Box 70576, Johnson City, TN 37614, USA
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16
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Menon B, Singh M, Ross RS, Johnson JN, Singh K. β-Adrenergic receptor-stimulated apoptosis in adult cardiac myocytes involves MMP-2-mediated disruption of β1 integrin signaling and mitochondrial pathway. Am J Physiol Cell Physiol 2006; 290:C254-61. [PMID: 16148033 DOI: 10.1152/ajpcell.00235.2005] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Stimulation of β-adrenergic receptors (β-AR) induces apoptosis in adult rat ventricular myocytes (ARVMs) via the JNK-dependent activation of mitochondrial death pathway. Recently, we have shown that inhibition of matrix metalloproteinase-2 (MMP-2) inhibits β-AR-stimulated apoptosis and that the apoptotic effects of MMP-2 are possibly mediated via its interaction with β1 integrins. Herein we tested the hypothesis that MMP-2 impairs β1 integrin-mediated survival signals, such as activation of focal adhesion kinase (FAK), and activates the JNK-dependent mitochondrial death pathway. Inhibition of MMP-2 using SB3CT, a selective gelatinase inhibitor, significantly increased FAK phosphorylation (Tyr-397 and Tyr-576). TIMP-2, tissue inhibitor of MMP-2, produced a similar increase in FAK phosphorylation, whereas treatment of ARVMs with purified active MMP-2 significantly inhibited FAK phosphorylation. Inhibition of MMP-2 using SB3CT inhibited β-AR-stimulated activation of JNKs and levels of cytosolic cytochrome c. Treatment of ARVMs with purified MMP-2 increased cytosolic cytochrome c release. Furthermore, inhibition of MMP-2 using SB3CT and TIMP-2 attenuated β-AR-stimulated decreases in mitochondrial membrane potential. Overexpression of β1 integrins using adenoviruses expressing the human β1A-integrin decreased β-AR-stimulated cytochrome c release and apoptosis. Overexpression of β1 integrins also inhibited apoptosis induced by purified active MMP-2. These data suggest that MMP-2 interferes with the β1 integrin survival signals and activates JNK-dependent mitochondrial death pathway leading to apoptosis.
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Affiliation(s)
- Bindu Menon
- Dept. of Physiology, James H. Quillen College of Medicine, East Tennessee State Univ., PO Box 70576, Johnson City, TN 37614, USA
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Massion PB, Pelat M, Belge C, Balligand JL. Regulation of the mammalian heart function by nitric oxide. Comp Biochem Physiol A Mol Integr Physiol 2005; 142:144-50. [PMID: 15985381 DOI: 10.1016/j.cbpb.2005.05.048] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2005] [Revised: 05/24/2005] [Accepted: 05/24/2005] [Indexed: 11/23/2022]
Abstract
The mammalian heart expresses all three isoforms of nitric oxide synthases (NOS) in diverse cell types of the myocardium. Despite their apparent promiscuity, the NOS isoforms support specific signaling because of their subcellular compartmentation with colocalized effectors and limited diffusibility of NO in muscle cells. eNOS and nNOS sustain normal EC coupling and contribute to the early and late phases of the Frank-Starling mechanism of the heart. They also attenuate the beta1-/beta2-adrenergic increase in inotropy and chronotropy, and reinforce the pre- and post-synaptic vagal control of cardiac contraction. By doing so, the NOS protect the heart against excessive stimulation by catecholamines, just as an "endogenous beta-blocker". In the ischemic and failing myocardium, induced iNOS further reinforces this effect, as does eNOS coupled to overexpressed beta3-adrenoceptors. nNOS expression also increases in the aging and infarcted heart, but its role (compensatory or deleterious) is less clear. In addition to their direct regulation of contractility, the NOS modulate oxygen consumption, substrate utilization, sensitivity to apoptosis, hypertrophy and regenerative potential, all of which illustrate the pleiotropic effects of this radical on the cardiac cell biology.
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Affiliation(s)
- Paul B Massion
- Unit of Pharmacology and Therapeutics, FATH 5349, Université catholique de Louvain, Tour Pasteur +2, 53 Avenue E. Mounier, 1200 Brussels, Belgium
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