Recent Findings Related to Cardiomyopathy and Genetics.

With the development and advancement of next-generation sequencing (NGS), genetic analysis is becoming more accessible. High-throughput genetic studies using NGS have contributed to unraveling the association between cardiomyopathy and genetic background, as is the case with many other diseases. Rare variants have been shown to play major roles in the pathogenesis of cardiomyopathy, which was empirically recognized as a monogenic disease, and it has been elucidated that the clinical course of cardiomyopathy varies depending on the causative genes. These findings were not limited to dilated and hypertrophic cardiomyopathy; similar trends were reported one after another for peripartum cardiomyopathy (PPCM), cancer therapy-related cardiac dysfunction (CTRCD), and alcoholic cardiomyopathy (ACM). In addition, as the association between clinical phenotypes and the causative genes becomes clearer, progress is being made in elucidating the mechanisms and developing novel therapeutic agents. Recently, it has been suggested that not only rare variants but also common variants contribute to the development of cardiomyopathy. Cardiomyopathy and genetics are approaching a new era, which is summarized here in this overview.

Nebivolol Prevents Up-Regulation of Nox2/NADPH Oxidase and Lipoperoxidation in the Early Stages of Ethanol-Induced Cardiac Toxicity.

Changes in redox state are described in the early stages of ethanol-induced cardiac toxicity. Here, we evaluated whether nebivolol would abrogate ethanol-induced redox imbalance in the heart. Male Wistar rats were treated with a solution of ethanol (20% v/v) for 3 weeks. Treatment with nebivolol (10 mg/kg/day; p.o. gavage) prevented the increase of both superoxide (O2•-) and thiobarbituric acid reactive substances (TBARS) in the left ventricle of rats chronically treated with ethanol. Neither ethanol nor nebivolol affected the expression of Nox4, p47phox, or Rac-1. Nebivolol prevented ethanol-induced increase of Nox2 expression in the left ventricle. Superoxide dismutase (SOD) activity as well as the concentration of reduced glutathione (GSH) was not altered by ethanol or nebivolol. Augmented catalase activity was detected in the left ventricle of both ethanol- and nebivolol-treated rats. Treatment with nebivolol, but not ethanol increased eNOS expression in the left ventricle. No changes in the activity of matrix metalloproteinase (MMP)2 or in the expressions of MMP2, MMP9, and tissue inhibitor metalloproteinase (TIMP)1 were detected after treatment with ethanol or nebivolol. However, ethanol increased the expression of TIMP2, and this response was prevented by nebivolol. Our results provided novel insights into the mechanisms underlying the early stages of the cardiac injury induced by ethanol consumption. We demonstrated that Nox2/NADPH oxidase-derived ROS play a role in ethanol-induced lipoperoxidation and that this response was prevented by nebivolol. In addition, we provided evidence that MMPs are not activated in the early stages of ethanol-induced cardiac toxicity.

The protective effect of fibroblast growth factor-21 in alcoholic cardiomyopathy: a role in protecting cardiac mitochondrial function.

Alcoholic cardiomyopathy (ACM) resulting from chronic alcohol misuse is one of the main contributors leading to heart failure and cardiovascular mortality. Fibroblast growth factor 21 (FGF21) is a well-established cardioprotective factor. We aimed to study the role of FGF21 in experimentally induced models and clinical affected patients with cardiac damage due to chronic alcohol consumption. We found that circulating FGF21 levels and cardiac FGF21 and ß-klotho protein levels were increased in subjects with chronic alcohol consumption. As an experimental model of ACM, we fed wild-type and Fgf21 knockout (Fgf21-/- ) mice with a 4% alcohol liquid diet for 4 and 12 weeks. FGF21 circulating levels and FGF21 expression in the myocardium were also increased in wild-type mice after chronic alcohol intake. Fgf21-/- mice develop a higher degree of cardiac hypertrophy, fibrosis, and cardiac dysfunction after chronic alcohol consumption than wild-type mice. Moreover, the myocardium of Fgf21-/- mice showed signs of metabolic deregulation, oxidative stress, and mitochondrial dysfunction after alcohol intake. Finally, human cardiac biopsies from patients with chronic alcohol consumption developing ACM presented a higher degree of oxidative stress which positively correlated with the FGF21 protein levels in the myocardium. We conclude that plasma levels and cardiac myocyte FGF21 expression were induced in response to chronic alcohol consumption. The lack of FGF21 aggravated cardiac damage produced by ACM, in association with enhanced mitochondrial and oxidative stress, thus pointing to FGF21 as a protective agent against development of alcohol-induced cardiomyopathy. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Cardiac Mitochondrial PTEN-L determines cell fate between apoptosis and survival during chronic alcohol consumption.

Chronic alcohol consumption induces myocardial damage and a type of non-ischemic cardiomyopathy termed alcoholic cardiomyopathy, where mitochondrial ultrastructural damages and suppressed fusion activity promote cardiomyocyte apoptosis. The aim of the present study is to determine the role of mitochondrial fission proteins and/or other proteins that localise on cardiac mitochondria for apoptosis upon ethanol consumption. In vivo and in vitro chronic alcohol exposure increased mitochondrial Drp1 levels but knockdown of the same did not confer cardioprotection in H9c2 cells. These cells displayed downregulated expression of MFN2 and OPA1 for Bak-mediated cytochrome c release and apoptosis. Dysregulated PTEN/AKT cell survival signal in both ethanol treated and Drp1 knockdown cells augmented oxidative stress by promoting  mitochondrial PTEN-L and MFN1 interaction. Inhibiting this interaction with VO-OHpic, a reversible PTEN inhibitor, prevented Bak insertion into the mitochondria and release of cytochrome c to cytoplasm. Thus, our study provides evidence that Drp1-mediated mitochondrial fission is dispensable for ethanol-induced cardiotoxicity and that stress signals induce mitochondrial PTEN-L accumulation for structural and functional dyshomeostasis. Our in vivo results also demonstrates the therapeutic potential of VO-OHpic for habitual alcoholics developing myocardial dysfunction.

The Effects of Ethanol on the Heart: Alcoholic Cardiomyopathy.

Alcoholic-dilated Cardiomyopathy (ACM) is the most prevalent form of ethanol-induced heart damage. Ethanol induces ACM in a dose-dependent manner, independently of nutrition, vitamin, or electrolyte disturbances. It has synergistic effects with other heart risk factors. ACM produces a progressive reduction in myocardial contractility and heart chamber dilatation, leading to heart failure episodes and arrhythmias. Pathologically, ethanol induces myocytolysis, apoptosis, and necrosis of myocytes, with repair mechanisms causing hypertrophy and interstitial fibrosis. Myocyte ethanol targets include changes in membrane composition, receptors, ion channels, intracellular [Ca2+] transients, and structural proteins, and disrupt sarcomere contractility. Cardiac remodeling tries to compensate for this damage, establishing a balance between aggression and defense mechanisms. The final process of ACM is the result of dosage and individual predisposition. The ACM prognosis depends on the degree of persistent ethanol intake. Abstinence is the preferred goal, although controlled drinking may still improve cardiac function. New strategies are addressed to decrease myocyte hypertrophy and interstitial fibrosis and try to improve myocyte regeneration, minimizing ethanol-related cardiac damage. Growth factors and cardiomyokines are relevant molecules that may modify this process. Cardiac transplantation is the final measure in end-stage ACM but is limited to those subjects able to achieve abstinence.

Effects of the (Pro)renin Receptor on Cardiac Remodeling and Function in a Rat Alcoholic Cardiomyopathy Model via the PRR-ERK1/2-NOX4 Pathway.

Alcoholic cardiomyopathy (ACM) caused by alcohol consumption manifests mainly as by maladaptive myocardial function, which eventually leads to heart failure and causes serious public health problems. The (pro)renin receptor (PRR) is an important member of the local tissue renin-angiotensin system and plays a vital role in many cardiovascular diseases. However, the mechanism responsible for the effects of PRR on ACM remains unclear. The purpose of this study was to determine the role of PRR in myocardial fibrosis and the deterioration of cardiac function in alcoholic cardiomyopathy. Wistar rats were fed a liquid diet containing 9% v/v alcohol to establish an alcoholic cardiomyopathy model. Eight weeks later, rats were injected with 1 × 109v.g./100 µl of recombinant adenovirus containing EGFP (scramble-shRNA), PRR, and PRR-shRNA via the tail vein. Cardiac function was assessed by echocardiography. Cardiac histopathology was measured by Masson's trichrome staining, immunohistochemical staining, and dihydroethidium staining. In addition, cardiac fibroblasts (CFs) were cultured to evaluate the effects of alcohol stimulation on the production of the extracellular matrix and their underlying mechanisms. Our results indicated that overexpression of PRR in rats with alcoholic cardiomyopathy exacerbates myocardial oxidative stress and myocardial fibrosis. Silencing of PRR expression with short hairpin RNA (shRNA) technology reversed the myocardial damage mediated by PRR. Additionally, PRR activated phosphorylation of ERK1/2 and increased NOX4-derived reactive oxygen species and collagen expression in CFs with alcohol stimulation. Administration of the ERK kinase inhibitor (PD98059) significantly reduced NOX4 protein expression and collagen production, which indicated that PRR increases collagen production primarily through the PRR-ERK1/2-NOX4 pathway in CFs. In conclusion, our study demonstrated that PRR induces myocardial fibrosis and deteriorates cardiac function through ROS from the PRR-ERK1/2-NOX4 pathway during ACM development.

Research Progress and Forensic Identification of Alcoholic Cardiomyopathy.

ABSTRACT: With the rapid development of the social economy in China, the incidence of diseases caused by excessive drinking is gradually increasing as well. Alcoholic cardiomyopathy refers to long-term high intake of ethanol, and has typical dilated cardiomyopathy characteristics, such as, hemodynamic changes, symptoms, signs, and morphological features. It is a kind of cardiomyopathy that excludes other causes of dilated cardiomyopathy. Due to the lack of specific pathological changes, the forensic pathological identification of alcoholic cardiomyopathy can only be based on the patient's medical history and by ruling out other causes of cardiomyopathy. This paper reviews the pathogenesis and forensic identification of alcoholic cardiomyopathy in order to provide reference for forensic pathologists and clinicians.

Atorvastatin reduces alcohol-induced endoplasmic reticulum stress in AC16 cardiomyocytes.

OBJECTIVES: To investigate the effects of atorvastatin on the ultrastructure and lipid metabolism of AC16 cardiomyocytes in response to alcohol-induced endoplasmic reticulum stress (ERS). DESIGN: The expression of the ERS-related factor GRP78 in the established ERS model was determined by western blotting. Alcohol-exposed cardiomyocytes were treated with various concentrations of atorvastatin, and GRP78 expression was measured. Cardiomyocyte ultrastructure was observed and SREBP-1c and triglyceride (TG) levels were evaluated. RESULTS: Exposure to ethanol for 0, 12, 24, and 48 h significantly affected GRP78 expression (0.19 ± 0.02, 0.27 ± 0.03, 0.39 ± 0.01, and 0.64 ± 0.02, respectively). GRP78 expression in the 1, 10, and 100 µmol L-1 atorvastatin-treated groups was 0.50 ± 0.04, 0.38 ± 0.03, and 0.24 ± 0.01, respectively, and significantly different from control group expression (0.19 ± 0.02); the expression in the alcohol group was 0.64 ± 0.02. Alcohol-treated AC16 cells had significantly larger and fewer mitochondria and disorganized cristae, often replaced by vacuoles. These aberrations decreased with increasing atorvastatin concentrations. SREBP-1c expression also differed significantly among all atorvastatin-treated and control groups (0.47 ± 0.04, 0.39 ± 0.03, and 0.31 ± 0.02; normal 0.25 ± 0.02; alcohol 0.56 ± 0.03). TG expression differed significantly between the 10 and 100 µmol L-1 groups (26.84 ± 1.63, 23.11 ± 2.05) and the alcohol group (36.35 ± 2.41). CONCLUSIONS: Atorvastatin inhibited the expression of the ERS-related factor GRP78 in response to alcohol exposure, improved cell morphology, and enhanced lipid metabolism in a cellular model of alcoholic cardiomyopathy.

Research Progress and Forensic Identification of Alcoholic Cardiomyopathy / 法医学杂志

With the rapid development of the social economy in China, the incidence of diseases caused by excessive drinking is gradually increasing as well. Alcoholic cardiomyopathy refers to long-term high intake of ethanol, and has typical dilated cardiomyopathy characteristics, such as, hemodynamic changes, symptoms, signs, and morphological features. It is a kind of cardiomyopathy that excludes other causes of dilated cardiomyopathy. Due to the lack of specific pathological changes, the forensic pathological identification of alcoholic cardiomyopathy can only be based on the patient's medical history and by ruling out other causes of cardiomyopathy. This paper reviews the pathogenesis and forensic identification of alcoholic cardiomyopathy in order to provide reference for forensic pathologists and clinicians.

Histopathologic features of alcoholic cardiomyopathy compared with idiopathic dilated cardiomyopathy.

BACKGROUND: The histologic difference between alcoholic cardiomyopathy (ACM) and idiopathic dilated cardiomyopathy (IDCM) is unclear. The present study aimed to identify the quantitative pathologic features of ACM compared with IDCM. METHODS: Specimens from 6 regions (anterior left ventricle [LV], lateral LV, inferior LV, interventricular septum [IVS], anterior right ventricle [RV], and inferior RV) were sampled from each explanted heart. Specimens from 4 healthy donor hearts were obtained as normal control. Tissues were sectioned and Masson trichrome stained. Histomorphometry was performed to evaluate the amount of myocyte, fibrosis, fatty tissue, and interstitium by Image-Pro Plus 6.0 (Media Cybernetics). RESULTS: A total of 408 specimens were obtained from 34 ACMs and 34 IDCMs; 8 specimens were obtained from 4 healthy donor hearts. Compared to healthy donor hearts, we observed an increase in fibrosis which replaces myocytes in myocardium of end-stage cardiomyopathy. The overall myocyte ratio in myocardium was 69.5 ±â€Š8.7% in ACM vs 71.9 ±â€Š7.4% in IDCM (P < .05). The percentage of interstitium was 10.8 ±â€Š4.8% in ACM vs 9.2 ±â€Š6.2% in IDCM (P < .05). A significant difference of fibrosis, fatty tissue was not discovered. Moreover, the myocyte area was 65.37 ±â€Š11.8% in ACM LV vs 70.03 ±â€Š9.0% in IDCM LV (P < .001). CONCLUSION: We described histologic characteristics in ACM and IDCM. There might be a quantitative difference of myocyte, interstitium in myocardium between ACM and IDCM, especially in LV. No difference was found in the percentage of fibrosis between the 2 groups.

Expression Profiling of Circular RNAs and Micrornas in Heart Tissue of Mice with Alcoholic Cardiomyopathy.

BACKGROUND/AIMS: Chronic heavy alcohol consumption may result in alcoholic cardiomyopathy. This study was designed to screen differentially expressed microRNAs and circular RNAs in heart tissue of mice with alcoholic cardiomyopathy to reveal the underlying molecular mechanism. METHODS: Having established a murine alcoholic cardiomyopathy model, we screened differentially expressed microRNAs and circular RNAs in three heart samples from the alcohol-treated and control groups by high-throughput microarray analysis. We analyzed the function and biological signaling pathways of differentially expressed non-coding RNAs closely related to alcoholic cardiomyopathy using bioinformatics software to identify some mRNAs and their biological signaling pathways closely related to alcoholic cardiomyopathy. RESULTS: Nineteen microRNAs and 265 circular RNAs were differentially expressed in the alcohol-treated group compared with the control group. After analyzing gene function and signaling pathways by bioinformatics software, we found that the differentially expressed mRNAs were associated with carbohydrate metabolism. CONCLUSIONS: Chronic alcohol consumption can change the non-coding RNA profile of heart tissue, which is closely related to the pathological mechanisms of alcoholic cardiomyopathy.

Role of autophagy and regulatory mechanisms in alcoholic cardiomyopathy.

Alcoholism is accompanied with a high incidence of cardiac morbidity and mortality due to the development of alcoholic cardiomyopathy, manifested as dilation of one or both ventricles, reduced ventricular wall thickness, myofibrillary disarray, interstitial fibrosis, hypertrophy and contractile dysfunction. Several theories have been postulated for the etiology of alcoholic cardiomyopathy including ethanol/acetaldehyde toxicity, mitochondrial production of reactive oxygen species, oxidative injury, apoptosis, impaired myofilament Ca2+ sensitivity and protein synthesis, altered fatty acid extraction and deposition, as well as accelerated protein catabolism. In particular, buildup of long-lived or dysfunctional organelles has been reported to contribute to cardiac structural and functional damage following alcoholism. Removal of cell debris and defective organelles by autophagy is essential to the maintenance of cardiac homeostasis in physiological and pathological conditions. However, insufficient understanding is currently available with regards to the involvement of autophagy in the pathogenesis of alcoholic cardiomyopathy. This review summarizes the recent findings on the pathophysiological role of dysregulated autophagy in one set and development of alcoholic cardiomyopathy. A thorough understanding of how autophagy is affected in alcoholism, and subsequently, contributes to the pathogenesis of alcoholic heart injury, will offer therapeutic guidance towards the management of alcoholic cardiomyopathy.

Acute ethanol exposure-induced autophagy-mediated cardiac injury via activation of the ROS-JNK-Bcl-2 pathway.

Binge drinking is associated with increased cardiac autophagy, and often triggers heart injury. Given the essential role of autophagy in various cardiac diseases, this study was designed to investigate the role of autophagy in ethanol-induced cardiac injury and the underlying mechanism. Our study showed that ethanol exposure enhanced the levels of LC3-II and LC3-II positive puncta and promoted cardiomyocyte apoptosis in vivo and in vitro. In addition, we found that ethanol induced autophagy and cardiac injury largely via the sequential triggering of reactive oxygen species (ROS) accumulation, activation of c-Jun NH2-terminal kinase (JNK), phosphorylation of Bcl-2, and dissociation of the Beclin 1/Bcl-2 complex. By contrast, inhibition of ethanol-induced autophagic flux with pharmacologic agents in the hearts of mice and cultured cells significantly alleviated ethanol-induced cardiomyocyte apoptosis and heart injury. Elimination of ROS with the antioxidant N-acetyl cysteine (NAC) or inhibition of JNK with the JNK inhibitor SP600125 reduced ethanol-induced autophagy and subsequent autophagy-mediated apoptosis. Moreover, metallothionein (MT), which can scavenge reactive oxygen and nitrogen species, also attenuated ethanol-induced autophagy and cell apoptosis in MT-TG mice. In conclusion, our findings suggest that acute ethanol exposure induced autophagy-mediated heart toxicity and injury mainly through the ROS-JNK-Bcl-2 signaling pathway.

[The forensic medical evaluation of the changes in the cerebral tissue in the case of sudden death from alcoholic cardiomyopathy]. / Sudebno-meditsinskaia otsenka strukturnykh izmenenii tkani golovnogo mozga v sluchaiakh vnezapnoi smerti ot alkogol'noi kardiomiopatii.

This article presents the results of the retrospective analysis of the protocols of forensic medical autopsies and histological studies of the cerebral tissues together with the data obtained by their statistical treatment. The objective of present work was to study and evaluate the structural changes in the cerebral tissues associated with sudden cardiac death from alcoholic cardiomyopathy. It was shown that the morphological changes in the endothelial lining of the microcirculatory bed of the cerebral tissue can be a consequence of both the direct cytotoxic action of ethanol or its metabolites and the influence of cellular modulators liberation of which results in enhanced vascular permeability associated with trophic disturbances in the tissue. These changes provide a substrate for the development of the dystrophic and necrobiotic processes in the main structural components of the organ in question. The clustering of glial cells around atrophic neutrons or instead of the dead ones in the brain as well as around the microcysts of the cerebral tissue as a compensatory response to the lesion can be in its turn considered as a pathognomonic sign of chronic alcoholic intoxication. The severe dystrophic and destructive processes proceeding in the main components of the histohematological barrier revealed in the cerebral tissue as a result of the present analysis are believed to reflect the toxic action of ethanol and/or its metabolites that play an important role in the development of dyscirculatory disorders responsibly for cerebral tissue hypoxia.

Hydrogen sulfide alleviates myocardial fibrosis in mice with alcoholic cardiomyopathy by downregulating autophagy.

Myocardial fibrosis is one of the most important pathological features of alcoholic cardiomyopathy (ACM). Hydrogen sulfide (H2S) exerts protective effects in various types of cardiovascular disease, which has been demonstrated by many previous studies. However, there is a lack of adequate research on the effect of H2S on myocardial fibrosis in ACM. The present study aimed to investigate the etiopathogenic role of H2S in myocardial fibrosis induced by chronic alcohol intake. An ACM mouse model was induced by consumption of 4% ethanol solution in drinking water for 12 weeks. Sodium hydrosulfide (NaHS) was used as a donor to provide exogenous H2S. Twelve weeks later, mice were sacrificed to calculate the heart to body weight ratio. The degree of myocardial collagen deposition was evaluated by Masson's and Van Gieson's staining, the expression level of collagen â…  was measured by immunohistochemistry and autophagosomes were observed by transmission electron microscopy. In addition, the expression levels of autophagy­associated proteins and fibrosis-associated proteins were detected by western blotting, and the expression levels of miR-21 and miR-211 were detected by reverse transcription-quantitative polymerase chain reaction. The outcomes of the study revealed that chronic alcohol intake results in myocardial fibrosis, enhanced myocardial collagen deposition and increased expression levels of collagen I, autophagy, autophagy-associated proteins (Beclin 1, Atg3 and Atg7) and fibrosis-associated proteins (MMP8, MMP13, MMP14, MMP17 and TGF-ß1), as well as miR-21 and miR-221. These results were markedly reversed following treatment with H2S. The present study confirmed that H2S relieves myocardial fibrosis in mice with ACM, and the underlying mechanism may involve the downregulation of autophagy and miR-21 and miR-211 expression levels.

Alcoholic Cardiomyopathy: Translation Model.

We developed a translation model of alcoholic cardiomyopathy in rats. By the end of forced alcoholization (the rats received 10% ethanol solution as the only source of fluid for 24 weeks; mean daily ethanol consumption was 5.0-6.5 g/kg), the rats developed dilated heart failure. Echocardiography and morphometric study of the myocardium revealed a decrease in inotropic function of the heart and dilatation of the right and left ventricles. Fatty degeneration of the myocardium (pathognomonic sign of alcoholic cardiomyopathy) and decrease in electrical stability of cardiomyocytes reliably reproduce the clinical pattern of alcoholic cardiomyopathy.

Etiology of alcoholic cardiomyopathy: Mitochondria, oxidative stress and apoptosis.

Putative mechanisms leading to the development of alcoholic cardiomyopathy (ACM) include the interrelated cellular processes of mitochondria metabolism, oxidative stress and apoptosis. As mitochondria fuel the constant energy demands of this continually contracting tissue, it is not surprising that alcohol-induced molecular changes in this organelle contribute to cardiac dysfunction and ACM. As the causal relationship of these processes with ACM has already been established, the primary objective of this review is to provide an update of the experimental findings to more completely understand the aforementioned mechanisms. Accordingly, recent data indicate that alcohol impairs mitochondria function assessed by membrane potential and respiratory chain activity. Indictors of oxidative stress including superoxide dismutase, glutathione metabolites and malondialdehyde are also adversely affected by alcohol oftentimes in a sex-dependent manner. Additionally, myocardial apoptosis is increased based on assessment of TUNEL staining and caspase activity. Recent work has also emerged linking alcohol-induced oxidative stress with apoptosis providing new insight on the codependence of these interrelated mechanisms in ACM. Attention is also given to methodological differences including the dose of alcohol, experimental model system and the use of males versus females to highlight inconsistencies and areas that would benefit from establishment of a consistent model.

Chronic Alcohol Intoxication Is Not Accompanied by an Increase in Calpain Proteolytic Activity in Cardiac Muscle of Rats.

Enzymatic activity of Ca2+-dependent calpain proteases as well as the content and gene expression of µ-calpain (activated by micromolar calcium ion concentrations), calpastatin (inhibitor of calpains), and titin (substrate for calpains) were investigated in cardiac muscles of rats subjected to chronic alcoholization for 3 and 6 months. There was no increase in the "heart weight/body weight" parameter indicating development of heart hypertrophy in the alcoholized rats, while a decreasing trend was observed for this parameter in the rats after 6-month modeling of alcoholic cardiomyopathy, which indicated development of atrophic changes in the myocardium. Fluorometric measurements conducted using the Calpain Activity Assay Kit did not reveal any changes in total calpain activity in protein extracts of cardiac muscles of the rats alcoholized for 3 and 6 months. Western blot analysis did not show reliable changes in the contents of µ-calpain and calpastatin, and SDS-PAGE did not reveal any decrease in the titin content in the myocardium of rats after the chronic alcohol intoxication. Autolysis of µ-calpain was also not verified, which could indicate that proteolytic activity of this enzyme in myocardium of chronically alcoholized rats is not enhanced. Using Pro-Q Diamond staining, changes in phosphorylation level of titin were not detected in cardiac muscle of rats after chronic alcoholization during three and six months. A decrease in µ-calpain and calpastatin mRNA content (~1.3-fold, p ≤ 0.01 and ~1.9-fold, p ≤ 0.01, respectively) in the myocardium of rats alcoholized for 3 months and decrease in calpastatin mRNA (~1.4-fold, p ≤ 0.01) in animals alcoholized for 6 months was demonstrated using real-time PCR. These results indicate negative effect of chronic alcohol intoxication on expression of the abovementioned genes.

Changes of desmin expression pattern in the myocardium of patients with alcoholic dilated cardiomyopathy.

INTRODUCTION: It has been suggested that desmin cytoskeleton remodeling may contribute to the progression of dilated cardiomyopathy and might affect long-term prognosis. This study is aiming at evaluating desmin expression in cardiomyocytes from patients with dilated cardiomyopathy of alcoholic etiology in advanced stages of the disease and comparing the results with measurements of normal heart tissue from control patients. MATERIALS AND METHODS: For immunohistochemistry, sections from 36 myocardium fragments taken from left ventricle of dilated cardiomyopathy patients were immunolabeled with an anti-desmin antibody and negative control slides were obtained by omitting the primary antibody. We calculated the ratios between the areas of myocardiocytes and the length and number of A dark disks and assessed the desmin expression level as the integrated optical density (IOD) and, respectively, the total areas of the signal given by immunolabeling. A Student's t-test has been utilized to assess the differences, p<0.05 deemed significant data. RESULTS: We identified significant decrease in numerical density of dark disks in our cases group compared with controls (p<0.05). Also, the ratios between total cellular area and total length of dark disks and number of dark disks was significantly different between cases and controls (p=0.04). IOD was significantly different between dilative cardiomyopathy cases and controls and also, overall desmin expression area was increased in dilatative cardiomyopathy patients. CONCLUSIONS: The identification of different desmin expression and standardization in diseased myocardium may be helpful in stratifying patients and in understanding their evolution, but also in finding new therapeutic targets that aim the alterations in desmin expression.

NOX2 amplifies acetaldehyde-mediated cardiomyocyte mitochondrial dysfunction in alcoholic cardiomyopathy.

Alcoholic cardiomyopathy (ACM) resulting from excess alcohol consumption is an important cause of heart failure (HF). Although it is assumed that the cardiotoxicity of the ethanol (EtOH)-metabolite acetaldehyde (ACA) is central for its development and progression, the exact mechanisms remain obscure. Murine cardiomyocytes (CMs) exposed to ACA or EtOH showed increased superoxide (O2(•-)) levels and decreased mitochondrial polarization, both being normalized by NADPH oxidase (NOX) inhibition. C57BL/6 mice and mice deficient for the ACA-degrading enzyme mitochondrial aldehyde dehydrogenase (ALDH-2(-/-)) were fed a 2% EtOH diet for 5 weeks creating an ACA-overload. 2% EtOH-fed ALDH-2(-/-) mice exhibited a decreased cardiac function, increased heart-to-body and lung-to-body weight ratios, increased cardiac levels of the lipid peroxidation product malondialdehyde (MDA) as well as increased NOX activity and NOX2/glycoprotein 91(phox) (NOX2/gp91(phox)) subunit expression compared to 2% EtOH-fed C57BL/6 mice. Echocardiography revealed that ALDH-2(-/-)/gp91(phox-/-) mice were protected from ACA-overload-induced HF after 5 weeks of 2% EtOH-diet, demonstrating that NOX2-derived O2(•-) contributes to the development of ACM. Translated to human pathophysiology, we found increased gp91(phox) expression in endomyocardial biopsies of ACM patients. In conclusion, ACM is promoted by ACA-driven mitochondrial dysfunction and can be improved by ablation of NOX2/gp91(phox). NOX2/gp91(phox) therefore might be a potential pharmacological target to treat ACM.