Increased myostatin activity and decreased myocyte proliferation in chronic alcoholic cardiomyopathy

miR-92a-3p regulates ethanol-induced apoptosis in H9c2 cardiomyocytes

The role of miR-92a-3p in the ethanol-induced apoptosis of H9c2 cardiomyocytes remains unclear. In this study, we explored the role of miR-92a-3p in the ethanol-induced apoptosis of H9c2 cardiomyocytes and identified its target genes and signaling pathways. H9c2 cells were cultured with or without 100 mM ethanol for 24 h. The differential expression of miR-92a-3p was verified in H9c2 cells through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). To manipulate the expression of miR-92a-3p, both a mimic and an inhibitor were transfected into H9c2 cells. An Annexin V-fluorescein isothiocyanate/propidium iodide apoptosis detection kit and apoptosis-related antibodies were used for apoptosis detection through flow cytometry and Western blotting, respectively. Target genes were verified through RT-qPCR, Western blotting, and double luciferase reporter gene assays. miR-92a-3p was significantly overexpressed in ethanol-stimulated H9c2 cardiomyocytes (P < 0.001). After ethanol stimulation, H9c2 myocardial cells exhibited increased apoptosis. The apoptosis rate was higher in the miR-92a-3p mimic group than in the control group. However, the apoptosis rate was lower in the miR-92a-3p inhibitor group than in the control group, indicating that miR-92a-3p promotes the ethanol-induced apoptosis of H9c2 myocardial cells. RT-qPCR and Western blotting revealed that the miR-92a-3p mimic and inhibitor significantly regulated the mRNA and protein expression levels of mitogen- and stress-activated protein kinase 2 and cyclic AMP-responsive element-binding protein 3-like protein 2 (CREB3L2), suggesting that miR-92a-3p promotes the apoptosis of H9c2 cardiomyocytes by inhibiting the MSK2/CREB/Bcl-2 pathway. Therefore, the apoptosis of H9c2 cardiomyocytes increases after ethanol stimulation, and miR-92a-3p can directly target MSK2 and CREB3L2, thereby promoting the ethanol-induced apoptosis of H9c2 myocardial cells.

Alcohol Intake Provoked Cardiomyocyte Apoptosis Via Activating Calcium-Sensing Receptor and Increasing Endoplasmic Reticulum Stress and Cytosolic [Ca2+]i

BACKGROUND

Cardiomyocyte apoptosis plays an important role in alcoholic cardiac injury. However, the association between calcium-sensing receptor (CaSR) and alcohol-induced cardiomyocyte apoptosis remain unclear. Therefore, we investigated the role and its moleculer mechanism of CaSR in rat cardiomyocyte apoptosis induced by alcohol.

METHODS

Alcohol-induced cardiomyocyte apoptosis in vivo and in vitro model of rats were applied in this study. The expression of CaSR, endoplasmic reticulum stress markers and apoptosis were tested by immunohistological staining, western blot, TUNEL and flow cytometry, respectively. [Ca2+]i were detected by confocal laser scanning microscopy.

RESULTS

Compared with the control group, alcohol intake (AI) led to abnormal arrangements of cardiomyocytes and obvious increase of myocardial apoptosis. Moreover, AI also significantly upregulated protein expression of CaSR, GRP94, caspase-12 and CHOP. Alcohol induced apoptosis of cultured cardiomyocytes of rats in a dose-dependent way. Activation of CaSR markedly enhanced cardiomyocyte apoptosis and ERS induced by alcohol, ERS inducer also significantly increased cardiomyocyte apoptosis without activating CaSR. Furthermore, GdCl3 augmented alcohol-induced increase of [Ca2+]i in cardiomyocytes, which was attenuated by NPS2390 but not 4-PBA pre-treatment.

CONCLUSIONS

Alcohol could induce cardiomyocyte apoptosis in rats in vivo and in vitro, which was mediated probably via activating CaSR, and then ERS and the increase of the cytosolic [Ca2+]i. This provides a potential target for preventing cardiomyocyte apoptosis and cardiomyopathy induced by alochol.

Myostatin: a potential therapeutic target for metabolic syndrome

Metabolic syndrome is a complex metabolic disorder, its main clinical manifestations are obesity, hyperglycemia, hypertension and hyperlipidemia. Although metabolic syndrome has been the focus of research in recent decades, it has been proposed that the occurrence and development of metabolic syndrome is related to pathophysiological processes such as insulin resistance, adipose tissue dysfunction and chronic inflammation, but there is still a lack of favorable clinical prevention and treatment measures for metabolic syndrome. Multiple studies have shown that myostatin (MSTN), a member of the TGF-β family, is involved in the development and development of obesity, hyperlipidemia, diabetes, and hypertension (clinical manifestations of metabolic syndrome), and thus may be a potential therapeutic target for metabolic syndrome. In this review, we describe the transcriptional regulation and receptor binding pathway of MSTN, then introduce the role of MSTN in regulating mitochondrial function and autophagy, review the research progress of MSTN in metabolic syndrome. Finally summarize some MSTN inhibitors under clinical trial and proposed the use of MSTN inhibitor as a potential target for the treatment of metabolic syndrome.

Serum Myostatin Predicts the Risk of Hepatocellular Carcinoma in Patients with Alcoholic Cirrhosis: A Multicenter Study

Background and Aim: Previous studies reported that serum myostatin is associated with sarcopenia. We aimed to elucidate the association between serum myostatin levels and hepatocellular carcinoma (HCC) development in patients with alcoholic liver cirrhosis (ALC). Methods: This retrospective, multicenter study assessed 1077 Asian ALC patients enrolled from 2007 to 2017. The primary endpoint was the development of HCC within 5 years. Cox proportional hazards model analyses were used to assess the association of serum myostatin levels and HCC development. The time-dependent areas under the receiver operating characteristic curve (AUROC) of serum myostatin for 5-year HCC development were calculated. Serum myostatin levels were measured using an enzyme-linked immunosorbent assay with samples collected on the index date. Results: During a median follow-up of 2.5 years, 5-year cumulative HCC incidence rates were 6.7% in the total population. The median level of serum myostatin was 3.3 ng/mL (interquartile, 2.1-5.2 ng/mL). The AUROC of serum myostatin for 5-year HCC development was 0.78 (95% confidence interval [CI], 0.76-0.81). In Cox proportional hazards model analyses, age, gender, platelet counts, and serum myostatin levels were independent risk factors for HCC development (adjusted hazard ratios [HRs] of age, male gender, platelet counts, and serum myostatin: 1.03, 2.79, 0.996, 1.18, respectively; all p < 0.05). Patients with high myostatin levels had a significantly higher risk of 5-year HCC development than those with low myostatin levels (HR 7.53, p < 0.001). Conclusion: Higher serum myostatin levels were significantly associated with a higher risk of developing HCC in ALC patients, which could identify high-risk patients who need stringent surveillance.

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.

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.

The Growth Differentiation Factor 11 (GDF11) and Myostatin (MSTN) in tissue specific aging

Growth differentiation factor 11 (GDF11) and myostatin (MSTN) are evolutionarily conserved homologues proteins which are closely related members of the transforming growth factor β superfamily. They are often perceived to serve similar or overlapping roles. Recently, GDF11 has been identified as playing a role during aging, however there are conflicting reports as to the nature of this role. In this review, we will discuss the literature regarding functions of GDF11 and myostatin in the heart, brain, and skeletal muscle during aging. Consequently we expect to develop a deeper understanding about the function of these two proteins in organismal aging and disease.

Cardiokines as Modulators of Stress-Induced Cardiac Disorders

Almost 30 years ago, the protein, atrial natriuretic peptide, was identified as a heart-secreted hormone that provides a peripheral signal from the myocardium that communicates to the rest of the organism to modify blood pressure and volume under conditions of heart failure. Since then, additional peripheral factors secreted by the heart, termed cardiokines, have been identified and shown to coordinate this interorgan cross talk. In addition to this interorgan communication, cardiokines also act in an autocrine/paracrine manner to play a role in intercellular communication within the myocardium. This review focuses on the roles of newly emerging cardiokines that are mainly increased in stress-induced cardiac diseases. The potential of these cardiokines as clinical biomarkers for diagnosis and prognosis of cardiac disorders is also discussed.

Plasma myostatin levels are related to the extent of right ventricular dysfunction in exacerbation of chronic obstructive pulmonary disease

OBJECTIVE

To investigate the relationship between plasma myostatin levels and right ventricle (RV) dysfunction (RVD) in acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

The study recruited 84 patients with AECOPD. Plasma myostatin was analyzed and tricuspid annular plane systolic excursion (TAPSE) < 16 mm was used as the main indicator for RVD.

RESULTS

Plasma myostatin levels were significantly higher in 47 patients with RVD than 37 ones without (P < 0.005). Multivariate regression analysis revealed that myostatin levels correlated significantly with TAPSE values and RV myocardial performance index (p < 0.001) among the study patients.

CONCLUSION

Plasma myostatin is a potential biomarker for improving diagnosis of RVD in AECOPD.

Tert-butylhydroquinone attenuates the ethanol-induced apoptosis of and activates the Nrf2 antioxidant defense pathway in H9c2 cardiomyocytes

Tert-butylhydroquinone (tBHQ), an inducer of nuclear factor erythroid 2-related factor 2 (Nrf2), has been demonstrated to attenuate oxidative stress-induced injury and the apoptosis of human neural stem cells and other cell types. However, whether tBHQ is able to exert a protective effect against oxidative stress and the apoptosis of cardiomyocytes has not yet been determined. Thus, the objective of the present study was to determine whether tBHQ protects H9c2 cardiomyocytes against ethanol-induced apoptosis. For this purpose, four sets of experiments were performed under standard culture conditions as follows: i) untreated control cells; ii) cell treatment with 200 mM ethanol; iii) cell treatment with 5 µM tBHQ; and iv) cell pre-treatment with 5 µM tBHQ for 24 h, followed by medium change and co-culture with 200 mM ethanol containing 5 µM tBHQ for a further 24 h. The viability of the cardiomyocytes was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of intracellular reactive oxygen species (ROS) and apoptosis were assessed by flow cytometry. Protein expression was measured by western blot analysis, and Nrf2 nuclear localization was observed by immunofluorescence. Exposure to ethanol led to a decrease in the protein expression of Nrf2 and its downstream antioxidant enzymes, accompanied by an increase in ROS generation and in the apoptosis of H9c2 cells. Pre-treatment with tBHQ significantly prevented the H9c2 cells from undergoing ethanol-induced apoptosis. tBHQ also increased the expression of B-cell lymphoma-2 (Bcl-2), whereas Bcl-2-associated X protein (Bax) expression was decreased. tBHQ promoted Nrf2 nuclear localization and increased the expression of Nrf2, superoxide dismutase (SOD), catalase (CAT) and heme oxygenase-1 (HO-1), and simultaneously inhibited the ethanol-induced overproduction of intracellular ROS. Therefore, tBHQ confers protection against the ethanol-induced apoptosis of and activates the Nrf2 antioxidant pathway in H9c2 cardiomyocytes.

Cardiovascular risks and benefits of moderate and heavy alcohol consumption

The heart and vascular system are susceptible to the harmful effects of alcohol. Alcohol is an active toxin that undergoes widespread diffusion throughout the body, causing multiple synchronous and synergistic effects. Alcohol consumption decreases myocardial contractility and induces arrhythmias and dilated cardiomyopathy, resulting in progressive cardiovascular dysfunction and structural damage. Alcohol, whether at binge doses or a high cumulative lifetime consumption-both of which should be discouraged-is clearly deleterious for the cardiovascular system, increasing the incidence of total and cardiovascular mortality, coronary and peripheral artery disease, heart failure, stroke, hypertension, dyslipidaemia, and diabetes mellitus. However, epidemiological, case-control studies and meta-analyses have shown a U-type bimodal relationship so that low-to-moderate alcohol consumption (particularly of wine or beer) is associated with a decrease in cardiovascular events and mortality, compared with abstention. Potential confounding influences-alcohol-dose quantification, tobacco use, diet, exercise, lifestyle, cancer risk, accidents, and dependence-can affect the results of studies of both low-dose and high-dose alcohol consumption. Mendelian methodological approaches have led to doubts regarding the beneficial cardiovascular effects of alcohol, and the overall balance of beneficial and detrimental effects should be considered when making individual and population-wide recommendations, as reductions in alcohol consumption should provide overall health benefits.

Alcoholic cardiomyopathy: pathophysiologic insights

Alcoholic cardiomyopathy (ACM) is a specific heart muscle disease found in individuals with a history of long-term heavy alcohol consumption. ACM is associated with a number of adverse histological, cellular, and structural changes within the myocardium. Several mechanisms are implicated in mediating the adverse effects of ethanol, including the generation of oxidative stress, apoptotic cell death, impaired mitochondrial bioenergetics/stress, derangements in fatty acid metabolism and transport, and accelerated protein catabolism. In this review, we discuss the evidence for such mechanisms and present the potential importance of drinking patterns, genetic susceptibility, nutritional factors, race, and sex. The purpose of this review is to provide a mechanistic paradigm for future research in the area of ACM.

Alcoholism: A systemic proinflammatory condition

Excessive ethanol consumption affects virtually any organ, both by indirect and direct mechanisms. Considerable research in the last two decades has widened the knowledge about the paramount importance of proinflammatory cytokines and oxidative damage in the pathogenesis of many of the systemic manifestations of alcoholism. These cytokines derive primarily from activated Kupffer cells exposed to Gram-negative intestinal bacteria, which reach the liver in supra-physiological amounts due to ethanol-mediated increased gut permeability. Reactive oxygen species (ROS) that enhance the inflammatory response are generated both by activation of Kupffer cells and by the direct metabolic effects of ethanol. The effects of this increased cytokine secretion and ROS generation lie far beyond liver damage. In addition to the classic consequences of endotoxemia associated with liver cirrhosis that were described several decades ago, important research in the last ten years has shown that cytokines may also induce damage in remote organs such as brain, bone, muscle, heart, lung, gonads, peripheral nerve, and pancreas. These effects are even seen in alcoholics without significant liver disease. Therefore, alcoholism can be viewed as an inflammatory condition, a concept which opens the possibility of using new therapeutic weapons to treat some of the complications of this devastating and frequent disease. In this review we examine some of the most outstanding consequences of the altered cytokine regulation that occurs in alcoholics in organs other than the liver.

Alcohol consumption and hormonal alterations related to muscle hypertrophy: a review

Detrimental effects of acute and chronic alcohol (ethanol) consumption on human physiology are well documented in the literature. These adversely influence neural, metabolic, cardiovascular, and thermoregulatory functions. However, the side effects of ethanol consumption on hormonal fluctuations and subsequent related skeletal muscle alterations have received less attention and as such are not entirely understood. The focus of this review is to identify the side effects of ethanol consumption on the major hormones related to muscle metabolism and clarify how the hormonal profiles are altered by such consumption.

Protective effects of hydrogen sulfide against chronic alcohol intake-induced left ventricular remodeling in rats

PURPOSE

To investigate the protective effects of hydrogen sulfide (H(2)S) against chronic alcohol intake-induced left ventricular remodeling and explore the potential mechanisms involved.

METHODS

Rats were randomly divided into 4 groups: alcohol group, NaHS group, alcohol + NaHS group, and control group. The echocardiographic and morphometric studies were performed to assess left ventricular remodeling. Oxidative stress was evaluated by detecting MDA, GSH-Px, Tot-SOD, CuZn-SOD and Mn-SOD in the supernatant. Cardiomyocyte apoptotic rate was determined by flow cytometry with Annexin V/PI staining. Western blotting was conducted to detect the expression of Bcl-2 family of apoptosis regulator proteins.

RESULTS

The echocardiographic and morphometric data indicated that H(2)S has protective effects against chronic alcohol intake-induced left ventricular remodeling. Our findings showed a significant increase in MDA level and decreases in GSH-Px, Tot-SOD, CuZn-SOD and Mn-SOD activities in the alcohol group compared to the control group, while in the alcohol + NaHS group, a significant decrease in MDA level and increases in GSH-Px, Tot-SOD, CuZn-SOD and Mn-SOD activities were found compared to the alcohol group. The apoptotic rate in the alcohol group was significantly higher than in the control group, whereas apoptotic rate in the alcohol + NaHS group was significantly lower than in the alcohol group. In addition, Bcl-2 and Bcl-xL expression was upregulated and Bax expression was downregulated in the alcohol + NaHS group compared to the alcohol group.

CONCLUSIONS

Our study demonstrates that H(2)S protects against chronic alcohol intake-induced left ventricular remodeling via attenuating oxidative stress and apoptosis.

Insulin-like growth factor 1 myocardial expression decreases in chronic alcohol consumption

Background

Alcoholic cardiomyopathy (CMP) is one of the major complications of chronic excessive alcohol consumption. The pathogenic mechanisms implicated are diverse, inducing functional and structural changes in the myocardium. Insulin-like Growth Factor 1 (IGF-1) plays an important role in modulating the cell cycle, and helps the differentiation and proliferation of cardiac tissue inhibiting apoptosis. Experimental studies have suggested the role of IGF-1 in alcohol-induced cardiac damage. The aim of the present study was to determine the effect of chronic alcohol consumption on IGF-1 myocardial expression and to compare this expression in cases of hypertension and other cardiac diseases.

Methods

We studied heart samples from human organ donors: 10 healthy donors, 16 with hypertension, 23 with chronic alcohol consumption and 7 with other causes of cardiac disease. IGF-1 myocardial expression was evaluated with a specific immunohistochemistry assay using a semi-quantitative method.

Results

A significant decrease in IGF-1 myocardial expression was observed comparing all the cases included with control donors. This decrease in IGF-1 myocardial expression was significantly lower in the group of donors with chronic alcohol consumption compared to controls. On group evaluation according to the presence of CMP, donors with chronic alcohol consumption without CMP presented significantly lower IGF-1 expression than controls, whereas donors with chronic alcohol consumption with CMP showed a downward trend without achieving significance.

Conclusions

Chronic alcohol consumption significantly reduces IGF-1 myocardial expression. This decrease induced by alcohol is partially compensated in the presence of structural myocardial damage.

Endocrine and clinical correlates of myostatin serum concentration in men--the STRAMBO study

CONTEXT

Myostatin is expressed mainly in skeletal muscle cells and acts as an inhibitor of muscle growth and differentiation. However, data on the determinants of serum myostatin concentrations in humans are limited.

OBJECTIVE

The aim of the study was to assess the correlates of serum myostatin concentrations in men.

DESIGN

We conducted a cross-sectional analysis of the STRAMBO cohort.

SETTING

Men holding private health insurance coverage with Mutuelle de Travailleurs de la Région Lyonnaise were included in the study.

PARTICIPANTS

A total of 1121 male volunteers aged 20-87 yr participated in the study.

INTERVENTIONS

Nonfasting blood samples were collected.

MAIN OUTCOME MEASURES

We measured the association of the investigated variables with circulating myostatin levels.

RESULTS

Serum myostatin levels increased slightly with age until 57 yr and then decreased. Circulating myostatin levels showed circannual variation, with the highest concentration in spring. In men older than 57 yr, serum myostatin levels decreased across increasing quartiles of body mass index and of total central and peripheral fat mass (P<0.05 to <0.001). Serum myostatin levels were positively correlated with serum levels of 25-hydroxycholecalciferol (25OHD), even after adjustment for season. Average myostatin levels were 0.47 sd higher in men with 25OHD above 40 ng/ml, compared with those with 25OHD below 20 ng/ml (P<0.05). Current smokers had lower myostatin concentration. Neither current physical activity nor serum levels of PTH, testosterone, and 17β-estradiol were associated with myostatin concentrations.

CONCLUSIONS

In men, circulating myostatin levels show seasonal changes and are associated with age, body mass index, fat mass, smoking, and 25OHD levels.

Myostatin is elevated in congenital heart disease and after mechanical unloading

BACKGROUND

Myostatin is a negative regulator of skeletal muscle mass whose activity is upregulated in adult heart failure (HF); however, its role in congenital heart disease (CHD) is unknown.

METHODS

We studied myostatin and IGF-1 expression via Western blot in cardiac tissue at varying degrees of myocardial dysfunction and after biventricular support in CHD by collecting myocardial biopsies from four patient cohorts: A) adult subjects with no known cardiopulmonary disease (left ventricle, LV), (Adult Normal), (n = 5); B) pediatric subjects undergoing congenital cardiac surgery with normal RV size and function (right ventricular outflow tract, RVOT), (n = 3); C) pediatric subjects with worsening but hemodynamically stable LV failure [LV and right ventricle (LV, RV,)] with biopsy collected at the time of orthotopic heart transplant (OHT), (n = 7); and D) pediatric subjects with decompensated bi-ventricular failure on BiVAD support with biopsy collected at OHT (LV, RV, BiVAD), (n = 3).

RESULTS

The duration of HF was longest in OHT patients compared to BIVAD. The duration of BiVAD support was 4.3±1.9 days. Myostatin expression was significantly increased in LV-OHT compared to RV-OHT and RVOT, and was increased more than double in decompensated biventricular HF (BiVAD) compared to both OHT and RVOT. An increased myostatin/IGF-1 ratio was associated with ventricular dysfunction.

CONCLUSIONS

Myostatin expression in increased in CHD, and the myostatin/IGF-1 ratio increases as ventricular function deteriorates. Future investigation is necessary to determine if restoration of the physiologic myostatin/IGF-1 ratio has therapeutic potential in HF.

Chronic alcohol consumption induces cardiac remodeling in mice from Th1 or Th2 background

AIMS

The effects of T helper (Th) cells on alcoholic cardiomyopathy have not been extensively investigated. Strain of mice with Th1 or Th2 immunological background were utilized in this study in order to explore the role of Th1/Th2 in chronic alcohol-induced cardiac fibrosis.

METHODS AND RESULTS

C57BL/6 WT or Balb/c mice were treated with alcohol for 90 days. Then cardiac structure and function were analyzed via echocardiography. Spleen CD4+CD25+Foxp3+ Tregs were determined by flow cytometry. The hearts were stained using haematoxylin and eosin (HE) and Masson's trichome. Myocardial ultrastructure was observed by electron microscopy. Expression of T-bet, GATA-3, IL-4 and IFN-gamma were determined by real-time RT-PCR. The heart was dilated significantly in the C57BL/6 WT+alcohol group and Balb/c+alcohol group compared with the controls. CD4+CD25+Foxp3+ Tregs were not statistically different. Masson's trichome staining revealed that fibrosis was more pronounced in the alcohol treated groups than the controls. Fibrosis was more evident in the Balb/c+alcohol group compared to the C57BL/6 WT+alcohol group. Alcohol consumption caused a decrease in the Th1 polarization and an increase in the Th2 response.

CONCLUSIONS

Chronic alcohol consumption induced a Th2 response within the Th1/Th2 balance. Th2 response is one of the underlying mechanism involved in alcohol-induced cardiac fibrosis.