cyclin-d1 and Heart-Failure

Topics: Adenoviridae; Animals; Cardiomegaly; Cell Cycle; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Genetic Therapy; Genetic Vectors; Heart Failure; Humans; Myocytes, Cardiac; Nuclear Localization Signals; Regenerative Medicine

Cardiomyopathy, a disorder of electrical or heart muscle function, represents a type of cardiac muscle failure and culminates in severe heart conditions. The prevalence of dilated cardiomyopathy (DCM) is higher than that of other types (hypertrophic cardiomyopathy and restrictive cardiomyopathy) and causes many deaths. Idiopathic dilated cardiomyopathy (IDCM) is a type of DCM with an unknown underlying cause. This study aims to analyze the gene network of IDCM patients to identify disease biomarkers. Data were first extracted from the Gene Expression Omnibus (GEO) dataset and normalized based on the RMA algorithm (Bioconductor package), and differentially expressed genes were identified. The gene network was mapped on the STRING website, and the data were transferred to Cytoscape software to determine the top 100 genes. In the following, several genes, including

Topics: Biomarkers; Cardiomyopathies; Cardiomyopathy, Dilated; Cyclin D1; Heart Failure; Humans; Myocardium

Glycogen storage disease type IV (GSD-IV) is an autosomal recessive disease caused by a deficiency in glycogen-branching enzyme (GBE1) activity that results in the accumulation of amylopectin-like polysaccharide, which presumably leads to osmotic swelling and cell death. This disease is extremely heterogeneous in terms of tissue involvement, age of onset and clinical manifestation. The most severe fetal form presents as hydrops fetalis; however, its pathogenetic mechanisms are largely unknown. In this study, mice carrying a stop codon mutation (E609X) in the Gbe1 gene were generated using a gene-driven mutagenesis approach. Homozygous mutants (Gbe(-/-) mice) recapitulated the clinical features of hydrops fetalis and the embryonic lethality of the severe fetal form of GSD-IV. However, contrary to conventional expectations, little amylopectin accumulation and no cell degeneration were found in Gbe(-/-) embryonic tissues. Glycogen accumulation was reduced in developing hearts of Gbe(-/-)embryos, and abnormal cardiac development, including hypertrabeculation and noncompaction of the ventricular wall, was observed. Further, Gbe1 ablation led to poor ventricular function in late gestation and ultimately caused heart failure, fetal hydrops and embryonic lethality. We also found that the cell-cycle regulators cyclin D1 and c-Myc were highly expressed in cardiomyocytes and likely contributed to cardiomyocyte proliferation and trabeculation/compaction of the ventricular wall. Our results reveal that early molecular events associated with Gbe1 deficiency contribute to abnormal cardiac development and fetal hydrops in the fetal form of GSD-IV.

Topics: 1,4-alpha-Glucan Branching Enzyme; Amylopectin; Animals; Cell Cycle Proteins; Cell Proliferation; Codon, Terminator; Cyclin D1; Embryo Loss; Fluorescent Antibody Technique; Genes, myc; Glycogen; Glycogen Storage Disease Type IV; Heart; Heart Defects, Congenital; Heart Failure; Heart Rate; Hydrops Fetalis; Mice; Myocytes, Cardiac; Polymerase Chain Reaction; Sequence Analysis, DNA; Ventricular Function

The ubiquitin-proteasome system (UPS) breaks down misfolded and normal proteins, including cell cycle regulatory proteins involved in cardiac hypertrophy. Because congestive heart failure (CHF) increases cardiomyocyte cellular mass, indicative of increased protein synthesis and/or impaired breakdown, and ventricular unloading decreases cardiac hypertrophy and changes regulation of multiple molecular systems ("reverse cardiac remodeling"), we tested the hypothesis that ventricular unloading alters myocardial UPS.. In 23 paired myocardial specimens (before and after unloading) ubiquitin, 20S proteasome, and cyclin D1 were investigated immunohistochemically and morphometrically quantified in relation to cardiomyocyte hypertrophy, DNA content, nuclear profile area and perimeter, and cyclin D1 protein expression. Moreover, 20S proteasome plasma concentrations were measured by enzyme-linked immunoassay (ELISA).. In CHF, sarcoplasmic 20S proteasome protein expression was significantly decreased compared with controls, but significantly increased after unloading. In contrast, sarcoplasmic ubiquitin protein was increased in CHF but significantly decreased after unloading, and both variables were inversely correlated. Cardiomyocyte 20S proteasome expression correlated inversely with cell size, mean DNA content, and cyclin D1, whereas ubiquitin protein expression was positively correlated with these parameters. The 20S proteasome plasma concentration was significantly increased after unloading.. Our data indicate that: (1) the UPS is depressed in CHF; and (2) this is reversed by ventricular unloading and associated with decreased cardiomyocyte hypertrophy, mean DNA content, and cell cycle regulatory proteins. The findings support the view that the UPS is involved in both the pathogenesis of cardiac hypertrophy and "reverse cardiac remodeling" after ventricular unloading.

Topics: Adolescent; Adult; Cell Nucleus; Child; Child, Preschool; Cyclin D1; Female; Heart Failure; Heart Transplantation; Heart-Assist Devices; Humans; Male; Middle Aged; Myocardium; Myocytes, Cardiac; Proteasome Endopeptidase Complex; Ubiquitin; Ventricular Remodeling; Young Adult

Cyclin D1, the retinoblastoma (Rb) protein, and the E2F transcription factors are involved in the pathogenesis of cardiac hypertrophy. Cyclin D1/cdk4 complexes, by phosphorylation, inactivate Rb, thereby abrogating its growth-inhibitory effect. Ventricular unloading is associated with reversible regulation of numerous cardiomyocyte molecular systems and decreased hypertrophy. Accordingly, the hypothesis whether the Rb/E2F-1 pathway is altered by ventricular unloading was tested, and correlations with the cyclin D1 protein expression and cardiomyocyte diameters were explored.. In 21 paired myocardial samples (before and after unloading) from patients with congestive heart failure (CHF), cyclin D1, phosphorylated Rb (pRb), its homologues p107 and p130 (pocket proteins), and E2F-1 were immunohistochemically investigated and morphometrically quantified. Cardiomyocyte diameters were morphometrically determined.. Cyclin D1 and the proteins of the Rb/E2F-1 pathway were significantly increased during CHF compared with controls and were significantly decreased after unloading. Cyclin D1, pRb, and p130 protein expression correlated significantly with cardiomyocyte diameters. A significant positive correlation was noted between the pocket proteins, E2F-1, and cyclin D1.. Increased protein expression of phosphorylated (inactivated) Rb and the pocket proteins is associated with cardiomyocyte hypertrophy in CHF. Rb inactivation might be explained by phosphorylation by increased numbers of cyclin D1/cdk4 complexes associated with cardiomyocyte hypertrophy. However, ventricular unloading can reversibly regulate this process. These data underscore the importance of cell cycle regulatory proteins in the pathogenesis of CHF-associated (maladaptive) cardiomyocyte hypertrophy and might offer novel clues for pharmacologic approaches of congestive heart failure.

Topics: Adolescent; Adult; Child; Child, Preschool; Crk-Associated Substrate Protein; Cyclin D1; E2F1 Transcription Factor; Female; Heart Failure; Heart Transplantation; Heart-Assist Devices; Humans; Hypertrophy; Male; Middle Aged; Myocytes, Cardiac; Retinoblastoma Protein; Retinoblastoma-Like Protein p107; Retrospective Studies; Signal Transduction; Ventricular Remodeling; Young Adult

Mechanical support in congestive heart failure (CHF) by a left ventricular assist device (LVAD) is associated with decreased cardiac hypertrophy and altered cardiomyocyte molecular pathways. Survivin initiates cell cycle progression by increased cyclinD1/cdk4 complexes by abrogation of the inhibitory effect of p16(INK4a) on cdk4. Accordingly, the role of survivin in CHF and after unloading was explored.. In 20 myocardial samples from patients with terminal CHF (before and after LVAD), the protein expression of survivin, cyclin D1, cdk4, p16(INK4a), and proliferating cell nuclear antigen (PCNA) was immunohistochemically investigated and morphometrically quantified by calculating the percentage of positive cardiomyocytes per visual field. These data were correlated with cardiomyocyte size and DNA content.. The mean percentage of cardiomyocytes immunoreactive against survivin, cyclin D1, cdk4, p16(INK4a), and PCNA was significantly increased in CHF compared with controls and significantly decreased after unloading (57.6% to 26.6%, 42% to 18.3%, 45.4% to 15.3%, 73.0% to 60.5%, and 43.5% to 25.2%, respectively; p < 0.05). All investigated parameters, in particular survivin and cyclin D1, significantly correlated with cardiomyocyte diameters (r = 0.405; r = 0.563) and DNA content (r = 0.430; r = 0.480), both in CHF (cardiac remodelling) and after unloading (p < 0.05).. These data indicate that survivin is reversibly regulated by ventricular unloading and might be involved in cell size/DNA content regulation and cardiomyocyte proliferation in cardiac remodelling during CHF. It is suggested that after ventricular unloading, decreased survivin protein expression might contribute to cardiac hypertrophy decrease by lowering the number of cyclin D1/cdk4 complexes.

Topics: Adolescent; Adult; Cell Cycle; Cell Size; Child; Child, Preschool; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p16; DNA; Female; Heart Failure; Heart-Assist Devices; Humans; Hypertrophy, Left Ventricular; Inhibitor of Apoptosis Proteins; Male; Microtubule-Associated Proteins; Middle Aged; Myocytes, Cardiac; Proliferating Cell Nuclear Antigen; Retrospective Studies; Survivin; Ventricular Remodeling; Young Adult

Cyclins and other cell-cycle regulators have been used in several studies to regenerate cardiomyocytes in ischaemic heart failure. However, proliferation of cardiomyocytes induced by nuclear-targeted cyclin D1 (D1NLS) stops after one or two rounds of cell cycles due in part to accumulation of p27Kip1, an inhibitor of cyclin-dependent kinase (CDK). Thus, expression of S-phase kinase-associated protein 2 (Skp2), a negative regulator of p27Kip1, significantly enhances the effect of D1NLS and CDK4 on cardiomyocyte proliferation in vitro. Here, we examined whether Skp2 can also improve cardiomyocyte regeneration and post-ischaemic cardiac performance in vivo.. Wistar rats underwent ischaemia/reperfusion injury by ligation of the coronary artery followed by injection of adenovirus vectors for D1NLS and CDK4 with or without Skp2. Enhanced proliferation of cardiomyocytes in the presence of Skp2 was demonstrated by increased expression of Ki67, a marker of proliferating cells (1.95% vs. 4.00%), and mitotic phosphorylated histone H3 (0.24% vs. 0.58%). Compared with rats that received only D1NLS and CDK4, expression of Skp2 improved left ventricular function as measured by the maximum and minimum rates of change in left ventricular pressure, the left ventricle end-diastolic pressure, left ventricle end-diastolic volume index, and the lung/body weight ratio.. Expression of Skp2 enhanced the effect of D1NLS and CDK4 on the proliferation of cardiomyocytes and further contributed to improved post-ischaemic cardiac function. Skp2 might be a versatile tool to improve the effect of cyclins on post-ischaemic regeneration of cardiomyocytes in vivo.

Topics: Adenoviridae; Animals; Animals, Newborn; Apoptosis; Cell Cycle; Cell Proliferation; Cyclin D1; Cyclin-Dependent Kinase 4; Disease Models, Animal; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Heart Failure; Mitosis; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Neovascularization, Physiologic; Rats; Rats, Sprague-Dawley; Regeneration; S-Phase Kinase-Associated Proteins; Time Factors; Ventricular Function, Left

Glycogen synthase kinase-3 (GSK-3) is a master regulator of growth and death in cardiac myocytes. GSK-3 is inactivated by hypertrophic stimuli through phosphorylation-dependent and -independent mechanisms. Inactivation of GSK-3 removes the negative constraint of GSK-3 on hypertrophy, thereby stimulating cardiac hypertrophy. N-terminal phosphorylation of the GSK-3 isoforms GSK-3alpha and GSK-3beta by upstream kinases (e.g., Akt) is a major mechanism of GSK-3 inhibition. Nonetheless, its role in mediating cardiac hypertrophy and failure remains to be established. Here we evaluated the role of Serine(S)21 and S9 phosphorylation of GSK-3alpha and GSK-3beta in the regulation of cardiac hypertrophy and function during pressure overload (PO), using GSK-3alpha S21A knock-in (alphaKI) and GSK-3beta S9A knock-in (betaKI) mice. Although inhibition of S9 phosphorylation during PO in the betaKI mice attenuated hypertrophy and heart failure (HF), inhibition of S21 phosphorylation in the alphaKI mice unexpectedly promoted hypertrophy and HF. Inhibition of S21 phosphorylation in GSK-3alpha, but not of S9 phosphorylation in GSK-3beta, caused phosphorylation and down-regulation of G1-cyclins, due to preferential localization of GSK-3alpha in the nucleus, and suppressed E2F and markers of cell proliferation, including phosphorylated histone H3, under PO, thereby contributing to decreases in the total number of myocytes in the heart. Restoration of the E2F activity by injection of adenovirus harboring cyclin D1 with a nuclear localization signal attenuated HF under PO in the alphaKI mice. Collectively, our results reveal that whereas S9 phosphorylation of GSK-3beta mediates pathological hypertrophy, S21 phosphorylation of GSK-3alpha plays a compensatory role during PO, in part by alleviating the negative constraint on the cell cycle machinery in cardiac myocytes.

Topics: Animals; Blood Pressure; Cardiomegaly; Cell Nucleus; Cell Proliferation; Cyclin D1; Cyclin G; Cyclin G1; Cyclins; E2F Transcription Factors; Gene Knock-In Techniques; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Heart Failure; Histones; Mice; Mice, Knockout; Myocardium; Myocytes, Cardiac; Phosphorylation

Chymase has been known as a local angiotensin II-generating enzyme in the cardiovascular system in dogs, monkeys, hamsters, and humans; however, recently it was reported that chymase also has various other functions. Therefore, we decided to examine whether the inhibition of chymase improves disease conditions associated with the pathophysiology of dilated cardiomyopathy in rats and its possible mechanism of action as rat chymase is unable to produce angiotensin II. We examined the effect of TY-51469, a novel chymase inhibitor (0.1 mg/kg/day [group CYI-0.1, n = 15] and 1 mg/kg/day [group CYI-1, n = 15]), in myosin-immunized postmyocarditis rats. Another group of myosin-immunized rats was treated with vehicle (group V, n = 15). Age-matched normal rats without immunization (group N, n = 10) were also included in the study. After 4 weeks of treatment, we evaluated cardiac function; area of fibrosis; fibrogenesis; levels of transforming growth factor (TGF)-beta1 and collagen III; hypertrophy and its marker, atrial natriuretic peptide (ANP); and mast cell activity. Survival rate and myocardial functions improved dose-dependently with chymase inhibitor treatment after myosin immunization. A reduction in the percent area of myocardial fibrosis, fibrogenesis, myocardial hypertrophy, and mast cell activity along with a reduction in TGF-beta1, collagen III, and ANP levels in the myocardium were noted in postmyocarditis rats that received chymase inhibitor treatment. The treatment also decreased myocardial aldosterone synthase levels in those animals. Inhibition of chymase reduces the pathogenesis of postmyocarditis dilated cardiomyopathy and progression to heart failure by preventing the pathological remodeling and residual inflammation in rats.

Topics: Animals; Atrial Natriuretic Factor; Autoimmune Diseases; Cardiomyopathy, Dilated; Chymases; Collagen Type III; Cyclin D1; Disease Progression; Enzyme Inhibitors; Heart Failure; Histamine; Humans; Macaca mulatta; Male; Myocarditis; Rats; Rats, Inbred Lew; Rats, Sprague-Dawley; Sulfonamides; Survival Rate; Thiophenes; Transforming Growth Factor beta1

Inflammatory mechanisms have been proposed to be important in heart failure (HF), and cytokines have been implicated to add to the progression of HF. However, it is unclear whether such mechanisms are already activated when hypertrophied hearts still appear well-compensated and whether such early mechanisms contribute to the development of HF.. In a comprehensive microarray study, galectin-3 emerged as the most robustly overexpressed gene in failing versus functionally compensated hearts from homozygous transgenic TGRmRen2-27 (Ren-2) rats. Myocardial biopsies obtained at an early stage of hypertrophy before apparent HF showed that expression of galectin-3 was increased specifically in the rats that later rapidly developed HF. Galectin-3 colocalized with activated myocardial macrophages. We found galectin-3-binding sites in rat cardiac fibroblasts and the extracellular matrix. Recombinant galectin-3 induced cardiac fibroblast proliferation, collagen production, and cyclin D1 expression. A 4-week continuous infusion of low-dose galectin-3 into the pericardial sac of healthy Sprague-Dawley rats led to left ventricular dysfunction, with a 3-fold differential increase of collagen I over collagen III. Myocardial galectin-3 expression was increased in aortic stenosis patients with depressed ejection fraction.. This study shows that an early increase in galectin-3 expression identifies failure-prone hypertrophied hearts. Galectin-3, a macrophage-derived mediator, induces cardiac fibroblast proliferation, collagen deposition, and ventricular dysfunction. This implies that HF therapy aimed at inflammatory responses may need to be targeted at the early stages of HF and probably needs to antagonize multiple inflammatory mediators, including galectin-3.

Topics: Animals; Animals, Genetically Modified; Aortic Valve Stenosis; Cardiomyopathy, Hypertrophic; Cell Division; Cyclin D1; Disease Progression; Extracellular Matrix; Fibroblasts; Galectin 3; Gene Expression Profiling; Gene Expression Regulation; Heart Failure; Humans; Macrophage Activation; Mice; Oligonucleotide Array Sequence Analysis; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; Stroke Volume; Ventricular Dysfunction, Left

Apoptosis may contribute to the myocardial dysfunction associated with heart failure (HF). Activation of the p38 MAPK cascade can induce apoptosis in non-cardiac cells through increased expression of Fas-L, or through decreased expression of cyclin D(1).. We tested the hypothesis that hypoxia (HX), angiotensin-II (A-II) and norepinephrine (NEPI) can mediate apoptosis by activating p38 MAPK, and thus initiating stimulus specific changes in Fas-L and cyclin D(1) expression in failing cardiomyocytes.. Cardiomyocytes isolated from ten dogs with HF induced by coronary microembolizations were subjected to HX or A-II or NEPI with and without a p38 MAPK inhibitor (SB 203580). TUNEL staining for DNA fragmentation and Western blots for p38 MAPK, Fas-L and cyclin D(1) detection were performed. HX-induced apoptosis was associated with increased Fas-L expression, A-II-induced apoptosis was associated with increased Fas-L and decreased cyclin D(1) expression, and NEPI-induced apoptosis was associated with decreased cyclin D(1) expression. Inhibition of p38 MAPK activity attenuated stress-induced apoptosis in all experiments and reversed changes in Fas-L and cyclin D(1) expression.. HX, A-II and NEPI mediate apoptosis in failing cardiomyocytes via different effects on Fas-L and cyclin D(1) expression. Inhibition of p38 MAPK reversed these effects, suggesting that apoptosis induced by HX, A-II and NEPI involves activation of p38 MAPK upstream from Fas-L and cyclin D(1).

Topics: Angiotensin II; Animals; Apoptosis; Cyclin D1; Disease Models, Animal; Dogs; Fas Ligand Protein; Follow-Up Studies; Heart Failure; Hypoxia; Incidence; Membrane Glycoproteins; Mitogen-Activated Protein Kinases; Models, Cardiovascular; Myocytes, Cardiac; Norepinephrine; p38 Mitogen-Activated Protein Kinases