Cardiomyopathy, Alcoholic

Alcohol intake provokes severe organ injuries including alcoholic cardiomyopathy with hallmarks of cardiac remodeling and contractile defects. This study examined the toxicity of facilitated ethanol metabolism in alcoholism-evoked changes in myocardial morphology and contractile function, insulin signaling and various cell death domains using cardiac-selective overexpression of alcohol dehydrogenase (ADH). WT and ADH mice were offered an alcohol liquid diet for 12 weeks prior to assessment of cardiac geometry, function, ER stress, apoptosis and ferroptosis. Alcohol intake provoked pronounced glucose intolerance, cardiac remodeling and contractile anomalies with apoptosis, ER stress, and ferroptosis, the effects were accentuated by ADH with the exception of global glucose intolerance. Hearts from alcohol ingesting mice displayed dampened insulin-stimulated phosphorylation of insulin receptor (tyr1146) and IRS-1 (tyrosine) along with elevated IRS-1 serine phosphorylation, the effect was augmented by ADH. Alcohol challenge dampened phosphorylation of Akt and GSK-3β, and increased phosphorylation of c-Jun and JNK, the effects were accentuated by ADH. Alcohol challenge promoted ER stress, FK506 binding protein 5 (FKBP5), YAP, apoptosis and ferroptosis, the effects were exaggerated by ADH. Using a short-term ethanol challenge model (3 g/kg, i.p., twice in three days), we found that inhibition of FKBP5-YAP signaling or facilitated ethanol detoxification by Alda-1 alleviated ethanol cardiotoxicity. In vitro study revealed that the ethanol metabolite acetaldehyde evoked cardiac contractile anomalies, lipid peroxidation, and apoptosis, the effects of which were mitigated by Alda-1, inhibition of ER stress, FKBP5 and YAP. These data suggest that facilitated ethanol metabolism via ADH exacerbates alcohol-evoked myocardial remodeling, functional defects, and insulin insensitivity possibly through a FKBP5-YAP-associated regulation of ER stress and ferroptosis.

Alcoholic cardiomyopathy (ACM) is a form of dilated cardiomyopathy (DCM) occurring secondary to long-standing heavy alcohol use and is associated with poor outcomes, but the cause-specific risks are insufficiently understood.

Between 1997 and 2018, we identified all patients with a first diagnosis of ACM or DCM. The cumulative incidence of different causes of hospitalisation and mortality in the two groups was calculated using the Fine-Gray and Kaplan-Meier methods.

A Total of 1,237 patients with ACM (mean age 56.3±10.1 years, 89% men) and 17,211 individuals with DCM (mean age 63.6±13.8 years, 71% men) were identified. Diabetes (10% vs 15%), hypertension (22% vs 31%), and stroke (8% vs 10%) were less common in ACM than DCM, whereas obstructive lung disease (15% vs 12%) and liver disease (17% vs 2%) were more prevalent (p<0.05). Cumulative 5-year mortality was 49% in ACM vs 33% in DCM, p<0.0001, multivariable adjusted hazards ratio 2.11 (95% confidence interval 1.97-2.26). The distribution of causes of death was similar in ACM and DCM, with the predominance of cardiovascular causes in both groups (42% in ACM vs 44% in DCM). 5-year cumulative incidence of heart failure hospitalisations (48% vs 54%) and any somatic cause (59% vs 65%) were also similar in ACM vs DCM. At 1 year, the use of beta blockers (55% vs 80%) and implantable cardioverter defibrillators (3% vs 14%) were significantly less often used in ACM vs DCM.

Patients with ACM had similar cardiovascular risks and hospitalisation patterns as other forms of DCM, but lower use of guideline-directed cardiovascular therapies and greater mortality.

Alcohol-induced cardiomyopathy (ACM) has a poor prognosis with up to a 50% chance of death within four years of diagnosis. There are limited studies investigating the potential of abstinence for promoting repair after alcohol-induced cardiac damage, particularly in a controlled preclinical study design. Here, we developed an exposure protocol that led to significant decreases in cardiac function in C57BL6/J mice within 30 days; dP/dt max decreased in the mice fed alcohol for 30 days (8054 ± 664.5 mmHg/s compared to control mice: 11,188 ± 724.2 mmHg/s, p < 0.01), and the dP/dt min decreased, as well (-7711 ± 561 mmHg/s compared to control mice: -10,147 ± 448.2 mmHg/s, p < 0.01). Quantitative PCR was used to investigate inflammatory and fibrotic biomarkers, while histology was used to depict overt changes in cardiac fibrosis. We observed a complete recovery of function after abstinence (dP/dt max increased from 8054 ± 664 mmHg/s at 30 days to 11,967 ± 449 mmHg/s after abstinence, p < 0.01); further, both inflammatory and fibrotic biomarkers decreased after abstinence. These results lay the groundwork for future investigation of the molecular mechanisms underlying recovery from alcohol-induced damage in the heart.