Alcohol use and congestive heart failure: incidence, importance, and approaches to improved history taking

miR-155-5p upregulation ameliorates myocardial insulin resistance via mTOR signaling in chronic alcohol drinking rats

Background

Chronic alcohol intake is associated with an increased risk of alcoholic cardiomyopathy, which may present with pathological changes such as myocardial insulin resistance, leading to ventricular dilation and cardiac dysfunction. Although a correlation between microRNA-155 (miR-155) and insulin signaling has been identified, the underlying mechanism has not been elucidated to date. The purpose of the study was to determine whether overexpression of miR-155-5p in vivo could ameliorate chronic alcohol-induced myocardial insulin resistance and cardiac dysfunction.

Material and Methods

Wistar rats were fed with either alcohol or water for 20 weeks to establish chronic alcohol intakes model. Then the alcohol group were divided into three groups: model group, miRNA-155 group and AAV-NC group. Rats undergoing alcohol treatment were injected with AAV-miRNA-155 (adeno-associated virus 9) or its negative control AAV-NC, respectively. Gene expression was determined by real-time PCR, and protein expression was determined by western blot. Echocardiography was performed to assess terminal cardiac function. Insulin responsiveness was determined through the quantification of phosphorylated insulin receptor substrate 1 (ser 307) and phosphorylated insulin receptor (Tyr 1185) levels.

Results

We found that cardiac function was attenuated in chronic alcohol intake rats, with an activated mammalian target of rapamycin (mTOR) signaling pathway, accompanied by an increase in p-IRS1(ser 307) and a decrease in p-IR (Tyr 1185) level in myocardial tissue. Also, alcohol drinking significantly up-regulated miR-155-5p level and its overexpression decreased p-IRS1 (ser 307) and increased p-IR (Tyr 1185) levels, and meanwhile inhibited the mTOR signaling pathway.

Conclusion

miR-155-5p upregulation ameliorates myocardial insulin resistance via the mTOR signaling in chronic alcohol drinking rats. We propose that miR-155 may serve as a novel potential therapeutic target for alcoholic heart disease.

Myocardial tissue and metabolism characterization in men with alcohol consumption by cardiovascular magnetic resonance and 11C-acetate PET/CT

BACKGROUND

Chronic alcohol consumption initially leads to asymptomatic left ventricular dysfunction, but can result in myocardial impairment and heart failure if ongoing. This study sought to characterize myocardial tissues and oxidative metabolism in asymptomatic subjects with chronic alcohol consumption by quantitative cardiovascular magnetic resonance (CMR) and 11C-acetate positron emission tomography (PET)/computed tomography (CT).

METHODS

Thirty-four male subjects (48.8 ± 9.1 years) with alcohol consumption > 28 g/day for > 10 years and 35 age-matched healthy male subjects (49.5 ± 9.7 years) underwent CMR and 11C-acetate PET/CT. Native and post T1 values and extracellular volume (ECV) from CMR and Kmono and K1 from PET imaging were measured. Quantitative measurements by CMR and PET imaging were compared between subjects with moderate to heavy alcohol consumption and healthy controls, and their correlations were also analyzed.

RESULTS

Compared to healthy controls, subjects with alcohol consumption showed significantly shorter native T1 (1133 ± 65 ms vs. 1186 ± 31 ms, p < 0.001) and post T1 (477 ± 42 ms vs. 501 ± 38 ms, p = 0.008) values, greater ECV (28.2 ± 2.2% vs. 26.9 ± 1.3%, p = 0.003), marginally lower Kmono (57.6 ± 12.1 min- 1 × 10- 3 vs. 63.0 ± 11.7 min- 1 × 10- 3, p = 0.055), and similar K1 (0.82 ± 0.13 min- 1 vs. 0.83 ± 0.15 min- 1, p = 0.548) after adjusting for confounding factors. There were no significant differences in CMR measurements and K1 between subjects with heavy and moderate alcohol consumption (all p > 0.05). In contrast, subjects with heavy alcohol consumption showed significantly lower Kmono values compared to those with moderate alcohol consumption (52.9 ± 12.1 min- 1 × 10- 3 vs. 63.7 ± 9.2 min- 1 × 10- 3, p = 0.012). Strong and moderate correlations were found between K1 and ECV in healthy controls (r = 0.689, p = 0.013) and subjects with moderate alcohol consumption (r = 0.518, p = 0.048), respectively.

CONCLUSION

Asymptomatic men with heavy alcohol consumption have detectable structural and metabolic changes in myocardium on CMR and 11C-acetate PET/CT. Compared with quantitative CMR, 11C-acetate PET/CT imaging may be more sensitive for detecting differences in myocardial damage among subjects with moderate to heavy alcohol consumption.

Valsartan inhibits RhoA-ROCK2-MYL pathway in rat model of alcoholic cardiomyopathy

The present study aimed to investigate variations in the Ras homolog gene family, member A (RhoA)-Rho-associated protein kinase 2 (ROCK2)-myosin light chain (MYL) pathway in a rat model of alcoholic cardiomyopathy (ACM) and the role of angiotensin-converting enzyme inhibitor drugs. Rat models of ACM were established via alcoholic gavage + free access to alcohol. The structural and functional changes of the heart were analyzed by hematoxylin-eosin staining, Masson's trichrome staining, immunohistochemistry staining, western blotting and fluorescence quantitative polymerase chain reaction. A total of 16 weeks later, a decreased ejection fraction and left ventricular fractional shortening in the alcohol group compared with the control group were demonstrated resulting in an increased left ventricular end diastolic diameter. These adverse effects were ameliorated following treatment with valsartan. In addition, the alcohol group revealed a disorganized arrangement of myocardial filaments, which was improved upon treatment with valsartan. RhoA and ROCK2 protein expression significantly increased in myocardial cells in the alcohol compared with the control group. Following drug intervention with valsartan, expression of RhoA and ROCK2 proteins were inhibited in the alcohol group. Furthermore, significantly elevated RhoA and ROCK2 and decreased MYL protein and mRNA expression in the alcohol group was demonstrated compared with the control group. Administration of valsartan reversed the expression profile of RhoA, ROCK and MYL in ACM. Expression of RhoA and ROCK were elevated with downregulation of MYL resulting in heart failure. However, the angiotensin receptor antagonist diminished the expression of RhoA and ROCK and enhanced the expression of MYL. The results of the present study suggest a curative effect of valsartan in ACM.

Role of Alcohol Oxidative Metabolism in Its Cardiovascular and Autonomic Effects

Several review articles have been published on the neurobehavioral actions of acetaldehyde and other ethanol metabolites as well as in major alcohol-related disorders such as cancer and liver and lung disease. However, very few reviews dealt with the role of alcohol metabolism in the adverse cardiac and autonomic effects of alcohol and their potential underlying mechanisms, particularly in vulnerable populations. In this chapter, following a brief overview of the dose-related favorable and adverse cardiovascular effects of alcohol, we discuss the role of ethanol metabolism in its adverse effects in the brainstem and heart. Notably, current knowledge dismisses a major role for acetaldehyde in the adverse autonomic and cardiac effects of alcohol because of its low tissue level in vivo. Contrary to these findings in men and male rodents, women and hypertensive individuals are more sensitive to the adverse cardiac effects of similar amounts of alcohol. To understand this discrepancy, we discuss the autonomic and cardiac effects of alcohol and its metabolite acetaldehyde in a model of hypertension, the spontaneously hypertensive rat (SHR) and female rats. We present evidence that enhanced catalase activity, which contributes to cardioprotection in hypertension (compensatory) and in the presence of estrogen (inherent), becomes detrimental due to catalase catalysis of alcohol metabolism to acetaldehyde. Noteworthy, studies in SHRs and in estrogen deprived or replete normotensive rats implicate acetaldehyde in triggering oxidative stress in autonomic nuclei and the heart via (i) the Akt/extracellular signal-regulated kinases (ERK)/nitric oxide synthase (NOS) cascade and (ii) estrogen receptor-alpha (ERα) mediation of the higher catalase activity, which generates higher ethanol-derived acetaldehyde in female heart. The latter is supported by the ability of ERα blockade or catalase inhibition to attenuate alcohol-evoked myocardial oxidative stress and dysfunction. More mechanistic studies are needed to further understand the mechanisms of this public health problem.

Quantifying the contribution of alcohol to cardiomyopathy: A systematic review

Alcohol has a direct toxic impact on the heart, and while there is an ICD code for alcoholic cardiomyopathy, the burden of alcohol-attributable cardiomyopathy is not clear. For the usual estimation of this burden via population-attributable fractions, one would need to determine the risk relationships, i.e., average risk associated with different dimensions of alcohol exposure. The most important among these risk relationships is the dose-response relationship with different levels of average alcohol consumption. To establish risk relationships, we systematically searched for all studies on dose-response relationships, directly and indirectly, via reviews. The results did not permit computation of pooled estimates through meta-analyses. There were clear indications that heavy drinking (≥80 g per day) over several years was linked to high risk of cardiomyopathy, with greater lifetime exposure of alcohol linked to higher risks. Some studies indicated potential effects of patterns of drinking as well. As such, the global quantification of alcohol-attributable cardiomyopathy will have to rely on other methods than those used conventionally.

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.

Patient, Caregiver, and Physician Work in Heart Failure Disease Management: A Qualitative Study of Issues That Undermine Wellness

OBJECTIVE

To identify factors underlying heart failure hospitalization.

METHODS

Between January 1, 2012, and May 31, 2012, we combined medical record reviews and cross-sectional qualitative interviews of multiple patients with heart failure, their clinicians, and their caregivers from a large academic medical center in the Midwestern United States. The interview data were analyzed using a 3-step grounded theory-informed process and constant comparative methods. Qualitative data were compared and contrasted with results from the medical record review.

RESULTS

Patient nonadherence to the care plan was the most important contributor to hospital admission; however, reasons for nonadherence were complex and multifactorial. The data highlight the importance of patient education for the purposes of condition management, timeliness of care, and effective communication between providers and patients.

CONCLUSION

To improve the consistency and quality of care for patients with heart failure, more effective relationships among patients, providers, and caregivers are needed. Providers must be pragmatic when educating patients and their caregivers about heart failure, its treatment, and its prognosis.

Investigation of microRNA expression profiles associated with human alcoholic cardiomyopathy

OBJECTIVES

We aimed to investigate the differentially expressed microRNAs (miRNAs) and their target genes in human alcoholic cardiomyopathy (ACM).

METHODS

The expression levels of plasma miRNAs of 78 male ACM patients and 78 healthy men were detected by using the 6th-generation miRCURY™ LNA array (v.16.0). The prediction analysis for microarrays (PAM) method was used to identify the differentially expressed miRNAs. Target genes of the identified differentially expressed miRNAs were predicted using TargetScan 5.2 and Miranda. Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to perform functional annotation and pathway enrichment analysis of target genes respectively, followed by real-time RT-PCR analysis to validate the expression changes of miRNAs.

RESULTS

Twenty-one differentially expressed miRNAs were identified. Nine differentially expressed miRNAs (hsa-miR-506, hsa-miR-1285, hsa-miR-512-3P, hsa-miR-138, hsa-miR-485-5P, hsa-miR-4262, hsa-miR-548c-3P, has-miR-548a-5P and kshv-miR-K12-1), involved in multiple functions and pathways, were selected for real-time RT-PCR confirmation. Moreover, two significantly important subpathways (neurotrophin signaling pathway and inositol phosphate metabolism) were predicted.

CONCLUSION

The screened differentially expressed miRNAs may be involved in the development of ACM. Specific miRNAs, such as miR-138, may be considered as a new target for the early diagnosis and treatment of human ACM.

A case of heart failure due to alcoholic cardiomyopathy combined with acute pulmonary embolism

It has not been reported that cases of alcoholic cardiomyopathy (ACM) combined with acute pulmonary embolism (PE). We hereby present a case of a 48-year-old male with ACM with significant enlargement of the heart and heart failure is described. Then, the patient was seized with acute PE which was confirmed by specific examination and his symptoms.

Comparison of patients rehospitalized for heart failure with versus without a history of habitual alcohol consumption

Alcohol paradoxically is known to have a protective and a deleterious effect on the heart. The effect of alcoholism on the growing problem of heart failure (HF) readmissions is not known. This study addressed this issue with a population of adult patients (>20 years old) who were readmitted for HF within 30 days after a hospitalization for HF at a university hospital in West Texas for a period of 5 years. Of the 204 patients with HF who were readmitted, 130 were admitted for HF exacerbations and 74 for unrelated medical conditions. Seventy-two (55%) were men, and the patients' mean age was 67 ± 15 years. Only 32 patients (24%) had a history of alcoholism. The mean age was significantly lower in patients with a history of alcoholism than in those without (62 ± 11 vs. 67 ± 15 years; P = 0.03), and there were more men in the group with a history of alcoholism (78% vs. 52%; P = 0.006). The mean ejection fraction was significantly lower in patients with a history of alcoholism than in those without (35 ± 19% vs. 39 ± 16%, P = 0.04). The length of stay was slightly longer in patients with a history of alcoholism, although the difference was not statistically significant (6 ± 5 vs. 5 ± 4 days; P = 0.52). Although alcohol contributed to only less than one quarter of hospital admissions, these patients were relatively younger and were predominantly males, compared to the sex-matched distribution of patients without a history of alcoholism.

Alcohol and immunology: Summary of the 2012 Alcohol and Immunology Research Interest Group (AIRIG) meeting

On October 27, 2012, the 17th annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the Grand Wailea Hotel in Maui, Hawaii as a satellite meeting to the 2012 Society of Leukocyte Biology conference. This year's meeting focused on the influence of alcohol on signal transduction pathways in various disease and injury models. Three plenary sessions were held where invited speakers shared their research on alcohol-mediated alterations of cell signaling components, immune cell subsets, and inflammation. These studies suggested alcohol has a negative effect on cell signaling machinery and immune cell homeostasis, resulting in disease, disease progression, and increased mortality. Researchers also identified tissue-specific alcohol-linked elevations in markers of inflammation, including cold-shock proteins and microRNAs. Additionally, one study revealed the effects of alcohol on immune cell subsets in a model of allergic asthma.

ALDH2 in alcoholic heart diseases: molecular mechanism and clinical implications

Alcoholic cardiomyopathy is manifested as cardiac hypertrophy, disrupted contractile function and myofibrillary architecture. An ample amount of clinical and experimental evidence has depicted a pivotal role for alcohol metabolism especially the main alcohol metabolic product acetaldehyde, in the pathogenesis of this myopathic state. Findings from our group and others have revealed that the mitochondrial isoform of aldehyde dehydrogenase (ALDH2), which metabolizes acetaldehyde, governs the detoxification of acetaldehyde formed following alcohol consumption and the ultimate elimination of alcohol from the body. The ALDH2 enzymatic cascade may evolve as a unique detoxification mechanism for environmental alcohols and aldehydes to alleviate the undesired cardiac anomalies in ischemia-reperfusion and alcoholism. Polymorphic variants of the ALDH2 gene encode enzymes with altered pharmacokinetic properties and a significantly higher prevalence of cardiovascular diseases associated with alcoholism. The pathophysiological effects of ALDH2 polymorphism may be mediated by accumulation of acetaldehyde and other reactive aldehydes. Inheritance of the inactive ALDH2*2 gene product is associated with a decreased risk of alcoholism but an increased risk of alcoholic complications. This association is influenced by gene-environment interactions such as those associated with religion and national origin. The purpose of this review is to recapitulate the pathogenesis of alcoholic cardiomyopathy with a special focus on ALDH2 enzymatic metabolism. It will be important to dissect the links between ALDH2 polymorphism and prevalence of alcoholic cardiomyopathy, in order to determine the mechanisms underlying such associations. The therapeutic value of ALDH2 as both target and tool in the management of alcoholic tissue damage will be discussed.

Chemical cardiomyopathies: the negative effects of medications and nonprescribed drugs on the heart

The heart is a target of injury for many chemical compounds, both medically prescribed and not medically prescribed. Pathophysiologic mechanisms underlying the development of chemical-induced cardiomyopathies vary depending on the inciting agent, including direct toxic effects, neurohormonal activation, altered calcium homeostasis, and oxidative stress. Numerous chemicals and drugs are implicated in cardiomyopathy. This article discusses examples of medication and nonprescribed drug-induced cardiomyopathies and reviews their pathophysiologic mechanisms.

Carnitine regulates myocardial metabolism by Peroxisome Proliferator-Activated Receptor-alpha (PPARalpha) in alcoholic cardiomyopathy

BACKGROUND

Chronic alcohol intake exerts myocardial damage en route to the development of alcoholic cardiomyopathy (ACM), although the precise pathogenesis of ACM is unknown. Carnitine is known to participate in the regulation of metabolism in a number of heart diseases. This study was designed to examine the interplay between myocardial metabolism and carnitine in the development of ACM.

MATERIAL/METHODS

Experimental animals were divided into 3 groups: (i) group A: alcohol-fed. (ii) group B: alcohol/carnitine: (200mg/kg/d, p.o. by mixing carnitine in rat chow). (iii) group C: control. Blood levels of free fatty acid (FFA), total carnitine (TC) and free carnitine (FC) were monitored in rats receiving alcohol with or without carnitine. Mitochondrial adenine nucleotide translocator-1 (ANT1) activity, ATPase activity, high energy phosphate concentration, peroxisome proliferator-activated receptor-α (PPARα), carnitine-palmitoyl transferase I (CPT-I), medium-chain acyl-coenzyme A dehydrogenase (MCAD), ANT1 and ATPase mRNA and protein expression were also monitored in myocardial tissue.

RESULTS

Experimental animals received alcohol with or without carnitine for six 6 months. Our results indicated that FFA increased abruptly. TC and FC were significantly decreased in groups receiving alcohol at 4 months. The concentration of ATP, ADP and AMP in the myocardium decreased following 2 months of alcohol administration. mRNA and protein expression of PPARα, CPT-I, MCAD, ANT1 and ATPase expressions were gradually altered in groups following alcohol feeding.

CONCLUSIONS

These observations suggest that abnormal metabolism is present in the myocardium during the development of ACM. Carnitine may improve myocardial metabolism by elevating the content of PPARα, CPT-I and MCAD.