Effect of alcohol on lipids and lipoproteins in relation to atherosclerosis

Sex-specific responses in glucose-insulin homeostasis and lipoprotein-lipid components after high-dose supplementation with marine n-3 PUFAs in abdominal obesity: a randomized double-blind crossover study

Background

Clinical studies on effects of marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and the plant-derived omega-6 (n-6) PUFA linoleic acid (LA) on lipoprotein-lipid components and glucose-insulin homeostasis have shown conflicting results, which may partly be explained by differential responses in females and males. However, we have lacked data on sexual dimorphism in the response of cardiometabolic risk markers following increased consumption of n-3 or n-6 PUFAs.

Objective

To explore sex-specific responses after n-3 (EPA + DHA) or n-6 (LA) PUFA supplementation on circulating lipoprotein subfractions, standard lipids, apolipoproteins, fatty acids in red blood cell membranes, and markers of glycemic control/insulin sensitivity among people with abdominal obesity.

Methods

This was a randomized double-blind crossover study with two 7-week intervention periods separated by a 9-week washout phase. Females (n = 16) were supplemented with 3 g/d of EPA + DHA (fish oil) or 15 g/d of LA (safflower oil), while males (n = 23) received a dose of 4 g/d of EPA + DHA or 20 g/d of LA. In fasting blood samples, we measured lipoprotein particle subclasses, standard lipids, apolipoproteins, fatty acid profiles, and markers of glycemic control/insulin sensitivity.

Results

The between-sex difference in relative change scores was significant after n-3 for total high-density lipoproteins (females/males: -11%*/-3.3%, p = 0.036; *: significant within-sex change), high-density lipoprotein particle size (+2.1%*/-0.1%, p = 0.045), and arachidonic acid (-8.3%*/-12%*, p = 0.012), and after n-6 for total (+37%*/+2.1%, p = 0.041) and small very-low-density lipoproteins (+97%*/+14%, p = 0.021), and lipoprotein (a) (-16%*/+0.1%, p = 0.028). Circulating markers of glucose-insulin homeostasis differed significantly after n-3 for glucose (females/males: -2.1%/+3.9%*, p = 0.029), insulin (-31%*/+16%, p < 0.001), insulin C-peptide (-12%*/+13%*, p = 0.001), homeostasis model assessment of insulin resistance index 2 (-12%*/+14%*, p = 0.001) and insulin sensitivity index 2 (+14%*/-12%*, p = 0.001), and quantitative insulin sensitivity check index (+4.9%*/-3.4%*, p < 0.001).

Conclusion

We found sex-specific responses after high-dose n-3 (but not n-6) supplementation in circulating markers of glycemic control/insulin sensitivity, which improved in females but worsened in males. This may partly be related to the sex differences we observed in several components of the lipoprotein-lipid profile following the n-3 intervention.

Clinical trial registration

https://clinicaltrials.gov/, identifier [NCT02647333].

Inhibition of Ceramide Synthesis Attenuates Chronic Ethanol Induced Cardiotoxicity by Restoring Lysosomal Function and Reducing Necroptosis

AIMS

Chronic alcohol misuse could cause alcoholic cardiomyopathy (ACM), and the specific mechanisms remained largely unknown. In this study, we aimed to explore the effects of endogenous ceramides on chronic ethanol-induced myocardial injury or cell loss (e.g. necroptosis).

METHODS

We established chronic alcohol intoxication models in vivo (male C57BL/6 mice) and in vitro (H9c2 cardiomyoblasts). The ceramide profiles were analyzed in mice myocardium and cultured cardiomyocytes. Further research on the role of ceramides and underlying signaling pathways was carried out in H9c2 cells.

RESULTS AND CONCLUSIONS

The ceramide profiles analysis revealed increased long and very long-chain ceramides in alcoholic myocardium and ethanol-treated cardiomyocytes. Next, we proved that endogenous ceramide inhibition could reduce necroptosis and alleviate cardiomyocytes injury as suggested by decreased levels of p-RIPK1, p-RIPK3 and p-MLKL proteins and cardiac injury factors expression. Furthermore, we found that lysosomal dysfunction also contributed to alcohol-induced cardiac damage and inhibiting ceramide biosynthesis could repaired this to some extent. Cells studies with exogenous C6 ceramide confirmed the pleotropic roles of ceramide in myocardial damage by causing both necroptosis and lysosomal dysfunction. Finally, our data suggested that lysosomal dysfunction could sensitize cardiomyocytes to induction of necroptosis due to the restriction on degradation of RIPK1/RIPK3 proteins. In conclusion, chronic ethanol treatment boosted myocardial ceramide synthesis in animal hearts and cultured cardiomyocytes. Moreover, ceramides exerted crucial roles in the intrinsic signaling pathways of alcohol-induced cardiotoxicity. Targeting ceramide biosynthesis to simultaneously attenuate necroptosis and lysosomal dysfunction might be a novel strategy for preventing alcoholic cardiotoxicity.

Hepatic artery disorders associated with alcoholism

OBJECTIVE

We aimed to characterize the relationship between severe chronic alcoholism and hepatic arterial wall disorders in humans.

METHODS

We obtained hepatic arteries from 165 patients undergoing liver transplantation who were placed into two etiological groups: an Alcoholism group and a Non-alcoholism group. We compared the age, sex, lipid profile, and histologic characteristics of the hepatic arteries (normal, reduction in luminal diameter of ≤10%, or atherosclerosis) of the participants in the two groups using multifactor analyses.

RESULTS

The Alcoholism group comprised 58 men and 40 women and the Non-alcoholism group comprised 63 men and 4 women. The mean ages of the groups were 52.5 ± 9.6 years and 44.2 ± 13.8 years, respectively. There were no circulating lipid abnormalities in any of the participants. In women, arterial disorders were found at a younger age than in men. Hepatic arterial disorders were more frequent in the non-alcoholic participants, and women with alcoholism showed less arterial narrowing.

CONCLUSION

The heavy consumption of alcoholic beverages is associated with a lower incidence of atherosclerosis of the hepatic artery in humans.

Long-Term Alcohol Consumption Caused a Significant Decrease in Serum High-Density Lipoprotein (HDL)-Cholesterol and Apolipoprotein A-I with the Atherogenic Changes of HDL in Middle-Aged Korean Women

Light-to-moderate alcohol drinking is associated with a low incidence of cardiovascular disease (CVD) via an elevation of high-density lipoproteins-cholesterol (HDL-C), particularly with the short-term supplementation of alcohol. However, there is no information on the change in the HDL qualities and functionalities between non-drinkers and mild drinkers in the long-term consumption of alcohol. This study analyzed the lipid and lipoprotein profiles of middle-aged Korean female non-drinkers, mild-drinkers, and binge-drinkers, who consumed alcohol for at least 10 years. Unexpectedly, the serum levels of HDL-C and apolipoprotein A-I (apoA-I) were decreased significantly depending on the alcohol amount; the binge-drinker group showed 18% and 13% lower HDL-C (p = 0.011) and apoA-I levels (p = 0.024), respectively, than the non-drinker group. Triglyceride (TG) and oxidized species, malondialdehyde (MDA), and low-density lipoproteins (LDL) levels were significantly elevated in the drinker groups. Interestingly, the binge-drinker group showed 1.4-fold higher (p = 0.020) cholesterol contents in HDL2 and 1.7-fold higher (p < 0.001) TG contents in HDL3 than those of the non-drinker group. The mild-drinker group also showed higher TG contents in HDL3 (p = 0.032) than the non-drinker group, while cholesterol contents were similar in the HDL3 of all groups. Transmission electron microscopy (TEM) showed that the non-drinker group showed a more distinct and clear particle shape of the LDL and HDL image with a larger particle size than the drinker group. Electrophoresis of LDL showed that the drinker group had faster electromobility with a higher smear band intensity and aggregation in the loading position than the non-drinker group. The HDL level of binge drinkers showed the lowest paraoxonase activity, the highest glycated extent, and the most smear band intensity of HDL and apoA-I, indicating that HDL quality and functionality were impaired by alcohol consumption. In conclusion, long-term alcohol consumption in middle-aged women, even in small amounts, caused a significant decrease in the serum HDL-C and apoA-I with atherogenic changes in LDL and HDL, such as an increase in TG and MDA content with a loss of paraoxonase activity.

Chronic Uptake of A Probiotic Nutritional Supplement (AB001) Inhibits Absorption of Ethylalcohol in the Intestine Tract - Results from a Randomized Double-blind Crossover Study

Background:

Regular alcohol consumption, e.g. by social drinking, is a potential source of consecutive health problems in many countries worldwide. A probiotic nutritional supplement (AB001) has been developed to reduce alcohol absorption from the intestine tract and to mitigate potential health care risks.

Methods:

This randomized placebo-controlled double-blind crossover study was conducted with 24 healthy subjects (13 male, 11 female, age: 25.4 ± 7.7 years, BMI: 23.6 ± 2.5 kg/m²). The subjects were randomized to take 2 capsules/day of AB001 or placebo for 1 week prior to an alcohol exposure experiment. On the experimental day, they ingested a light breakfast and drank a moderate glass of spirit (0.3 g/kg body weight). Breath alcohol tests and blood draws for determination of blood alcohol levels were performed for up to 6 hours. After crossover, the experiment was repeated in the following week. Areas under the curves were calculated to determine alcohol absorption rates.

Results:

A significant reduction of blood alcohol levels by 70.3% (P < 0.005 vs. placebo) was seen with AB001, (breath test: −30.7%; P < 0.005 vs. placebo). No difference was seen in a cognitive function test performed 60 minutes after alcohol ingestion (22.4 ± 7.7 seconds vs. 22.7 ± 5.6 seconds, n.s.). There were no adverse events or serious adverse events reported in this study

Conclusions:

One week of supplementation with AB001 resulted in a substantially reduced absorption of alcohol into the body. Regular uptake of AB001 may help to prevent liver and other organ damage, and may reduce the negative medical and economical impact of social drinking on the individual and the society.

Moderate alcohol consumption and lipoprotein subfractions: a systematic review of intervention and observational studies

CONTEXT

Moderate alcohol consumption is associated with decreased risk of cardiovascular disease (CVD) and improvement in cardiovascular risk markers, including lipoproteins and lipoprotein subfractions.

OBJECTIVE

To systematically review the relationship between moderate alcohol intake, lipoprotein subfractions, and related mechanisms.

DATA SOURCES

Following PRISMA, all human and ex vivo studies with an alcohol intake up to 60 g/d were included from 8 databases.

DATA EXTRACTION

A total of 17 478 studies were screened, and data were extracted from 37 intervention and 77 observational studies.

RESULTS

Alcohol intake was positively associated with all HDL subfractions. A few studies found lower levels of small LDLs, increased average LDL particle size, and nonlinear relationships to apolipoprotein B-containing lipoproteins. Cholesterol efflux capacity and paraoxonase activity were consistently increased. Several studies had unclear or high risk of bias, and heterogeneous laboratory methods restricted comparability between studies.

CONCLUSIONS

Up to 60 g/d alcohol can cause changes in lipoprotein subfractions and related mechanisms that could influence cardiovascular health.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. 98955.

Schisandrin B Protects against Acute Ethanol-Induced Cardiac Injury by Downregulating Autophagy via the NOX4/ROS Pathway

INTRODUCTION

Although oxidative stress has been demonstrated to mediate acute ethanol-induced changes in autophagy in the heart, the precise mechanism behind redox regulation in acute ethanol heart disease remains largely unknown.

METHODS

Wild-type C57BL/6 mice were intraperitoneally injected with ethanol (3 g/kg/day) for 3 consecutive days. The effects of ethanol on cultured primary cardiomyocytes and H9c2 myoblasts were also studied in vitro. Levels of autophagic flux, cardiac apoptosis and function, reactive oxygen species (ROS) accumulation, NOX4, and NOX2 were examined. The NOX4 gene was knocked down with NOX4 siRNA.

RESULTS

In this study, we demonstrated that schisandrin B inhibited acute ethanol-induced autophagy and sequent apoptosis. In addition, schisandrin B treatment improved cardiac function in ethanol-treated mice. Furthermore, NOX4 protein expression was increased during acute ethanol exposure, and the upregulation of NOX4 was significantly inhibited by schisandrin B treatment. The knockdown of NOX4 prevented ROS accumulation, cell autophagy, and apoptosis.

CONCLUSION

These results highlight that NOX4 is a critical mediator of ROS and elaborate the role of the NOX4/ROS axis in the effect of schisandrin B on autophagy and autophagy-mediated apoptosis in acute ethanol exposure, which suggests a therapeutic strategy for acute alcoholic cardiomyopathy.

Deletion of the E3 ubiquitin ligase, Parkin, exacerbates chronic alcohol intake-induced cardiomyopathy through an Ambra1-dependent mechanism

BACKGROUND AND PURPOSE

Chronic alcohol consumption contributes to contractile dysfunction and unfavourable geometric changes in myocardium, accompanied by altered autophagy and disturbed mitochondrial homeostasis. The E3 ubiquitin ligase Parkin encoded by PARK2 gene maintains a fundamental role in regulating mitophagy and mitochondrial homeostasis, although little is known of its role in the aetiology of alcoholic cardiomyopathy. Here we assessed the effects of Parkin deletion in chronic alcohol-evoked cardiotoxicity.

EXPERIMENTAL APPROACH

Following alcohol (4%) or control diet intake for 8 weeks, adult male wild-type (WT) and PARK2 knockout (Parkin^-/- ) mice were examined using echocardiography. Cardiomyocyte mechanical properties, morphology of myocardium, and mitochondrial damage were also evaluated. Autophagy and mitophagy levels were assessed by LC3B and GFP-LC3 puncta, and lysosome-dependent autophagic flux was scrutinized using GFP-mRFP-LC3 puncta and Bafilomycin A1 treatment.

KEY RESULTS

Chronic alcohol exposure provoked unfavourable geometric changes in myocardium and led to mitochondrial dysfunction and cardiac contractile defects, effects further exacerbated by Parkin knockout. Chronic alcohol exposure provoked autophagy and PINK1/Parkin-mediated mitophagy without affecting lysosome-dependent autophagic flux, the effects of which were diminished by Parkin deletion. Parkin adenovirus infection in neonatal rat cardiomyocytes further increased autophagy and protected against alcohol-induced myocardial injury, effects blocked by siRNA for Ambra1 (Autophagy and Beclin1 regulator 1). Immunofluorescence staining and co-immunoprecipitation assays showed interactions between Parkin and Ambra1.

CONCLUSIONS AND IMPLICATIONS

Parkin was essential for cardiac homeostasis in alcohol challenge, accompanied by increased autophagy/mitophagy and maintenance of mitochondrial integrity through its interaction with Ambra1.

Lipid reference values in an Irish population

BACKGROUND AND AIMS

There is limited information on reference values for lipids and lipoproteins in an Irish population. In this observational study, we have described the distributions of lipids in a large Irish cohort.

METHODS

Over 110,000 lipid profiles were selected from a database of almost 1.5 million consecutive lipid profiles performed in the Clinical Biochemistry Laboratory in University Hospital Galway between 2004 and 2017 to best represent the Irish population. Age- and sex-related reference intervals for both sexes for total cholesterol, triglycerides, HDL cholesterol and LDL cholesterol, from the age of ten to greater than 90 years, were determined. Two methods for estimating LDL cholesterol were also compared.

RESULTS

Sex-related differences in lipid distributions arise before the age of 20 years and are life-long. In both sexes total and LDL cholesterol levels gradually increased towards middle age with a decrease towards old age. Levels tended to be higher in males than in females up to mid-life at which stage they cross over with females having on average higher levels. The median of the triglyceride distributions show similar age- and sex-related changes to total cholesterol, but the distributions show a very marked positive skew that is particularly obvious in middle aged males. HDL cholesterol distributions change little throughout life with males having lower levels than females. Changing from the Friedewald formula to that proposed by Martin would impact the management of some patients with dyslipidaemia.

CONCLUSIONS

This study provides lipid reference values for clinical biochemistry laboratories and clinicians working in Ireland. It is informative for public health initiatives wishing to target dyslipidaemia as a modifiable risk for cardiovascular disease and for investigators researching geographical and temporal variances in lipid parameters.

The association of religious affiliation with cholesterol levels among South Asians: the Mediators of Atherosclerosis in South Asians Living in America study

Background

South Asians have disproportionately high rates of cardiovascular disease. Dyslipidemia, a contributing factor, may be influenced by lifestyle, which can vary by religious beliefs. Little is known about South Asian religions and associations with dyslipidemia.

Methods

Cross-sectional analyses of the MASALA study (n = 889). We examined the associations between religious affiliation and cholesterol levels using multivariate linear regression models. We determined whether smoking, alcohol use, physical activity, and dietary pattern mediated these associations.

Results

Mean LDL was 112 ± 32 mg/dL, median HDL was 48 mg/dL (IQR:40–57), and median triglycerides was 118 mg/dL (IQR:88–157). Muslims had higher LDL and triglycerides, and lower HDL, while participants with no religious affiliation had lower LDL and higher HDL. The difference in HDL between Muslims and those with no religious affiliation was partly explained by alcohol consumption.

Conclusions

Religion-specific tailoring of interventions designed to promote healthy lifestyle to reduce cholesterol among South Asians may be useful.

Alcohol Consumption in Combination with an Atherogenic Diet Increased Indices of Atherosclerosis in Apolipoprotein E/Low-Density Lipoprotein Receptor Double-Knockout Mice

BACKGROUND

Alcohol abuse and adherence to atherogenic diet (AD; a low-carbohydrate-high-protein diet) have been positively associated with cardiovascular disease. In addition, it has been demonstrated clinically that dietary intake is increased on days when alcohol is consumed. Here, the additive effects of ethanol (EtOH) and AD on atherosclerosis, a major underlying cause of cardiovascular disease, were investigated in apolipoprotein E/low-density lipoprotein receptor double-knockout (KO) mice. The mechanisms, especially aortic oxidative stress damage, were highlighted.

METHODS

Twelve-week-old male KO mice on AD with or without EtOH treatment were bred for 4 months. Age-matched male C57BL/6J mice on a standard chow diet without EtOH treatment served as controls. Analyses were conducted using ultrasound biomicroscopy, histopathological and fluorescence immunohistochemical examinations, Western blots, and polymerase chain reaction.

RESULTS

KO mice on AD with EtOH treatment showed increases in aortic maximum intima media thickness, hypoechoic plaque formation, and mean Oil-Red-O content. These results were associated with enhanced ratio of aortic 8-hydroxy-2'-deoxyguanosine (8-OHdG)-immunopositive area to the metallothionein (MT) immunopositive area and suppression of AD-induced up-regulated aortic Mt1, Mt2, and upstream stimulatory factor 1 mRNA expressions. Moreover, 8-OHdG was expressed in the nuclei of CD31- and alpha smooth muscle actin-immunopositive cells, and the up-regulated mRNA expressions of aortic nitric oxide synthase 3 and platelet-derived growth factors were only observed in the KO mice on AD with EtOH treatment.

CONCLUSIONS

Alcohol abuse and adherence to AD may promote the shift of aortic oxidative stress and antioxidative stress balance toward oxidative stress predominance and reduced antioxidative stress, which may be partly due to the decrease in MT at the cell biological level and down-regulation of Mt at the gene level, which in turn could play a role in the up-regulation of endothelial dysfunction-related and vascular smooth muscle cell proliferation-related gene expression and the progression of atherosclerosis in mice with hyperlipidemia.

The prevalence and risk factors of dyslipidemia in different diabetic progression stages among middle-aged and elderly populations in China

Objectives

This study aimed to examine the prevalence and risk factors of dyslipidemia in different diabetic progression stages among middle-aged and elderly Chinese populations.

Methods

The 2010–2012 China National Nutrition and Health Survey (CNNHS) is a nationally representative cross-sectional study. In the present study, a total of 69,974 participants aged ≥ 45 years were included. Dyslipidemia was defined based on the Chinese adult dyslipidemia prevention guide. A multivariable logistic regression model was performed to examine the associations between risk factors and dyslipidemia.

Results

The prevalence of dyslipidemia was 39.9%, 46.8%, and 59.3% in participants with normal glucose, prediabetes, and type 2 diabetes mellitus (T2DM). Women had a lower dyslipidemia prevalence than men (38.7% vs. 43.3%). Dyslipidemia prevalence was positively associated with the education level and inversely correlated with the physical activity level, and negatively related to age only among prediabetes and T2DM groups (P for trend < 0.05). Obesity, abdominal obesity, and hypertension were associated with dyslipidemia.

Conclusions

The prevalence of dyslipidemia was relatively high among middle-aged and elderly T2DM person. There are different associations between multiple risk factors and dyslipidemia in different diabetic progression stages.

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.

Chronic ethanol increases calcium/calmodulin-dependent protein kinaseIIδ gene expression and decreases monoamine oxidase amount in rat heart muscles: Rescue effect of Zingiber officinale (ginger) extract

OBJECTIVE

Association between chronic alcohol intake and cardiac abnormality is well known; however, the precise underlying molecular mediators involved in ethanol-induced heart abnormalities remain elusive. This study investigated the effect of chronic ethanol exposure on calcium/calmodulin-dependent protein kinase IIδ (CaMKIIδ) gene expression and monoamine oxidase (MAO) levels and histological changes in rat heart. It was also planned to find out whether Zingiber officinale (ginger) extract mitigated the abnormalities induced by ethanol in rat heart.

METHODS

Male wistar rats were divided into three groups of eight animals each: control, ethanol, and ginger extract treated-ethanol (GETE) groups.

RESULTS

After 6 weeks of treatment, the results revealed a significant increase in CaMKIIδtotal and isoforms δ2 and δ3 of CaMKIIδ gene expression as well as a significant decrease in the MAO levels in the ethanol group compared to that in the control group. Moreover, compared to the control group, the ethanol group showed histological changes, such as fibrosis, heart muscle cells proliferation, myocyte hypertrophy, vacuolization, and focal lymphocytic infiltration. Consumption of ginger extract along with ethanol ameliorated CaMKIIδtotal. In addition, compared to the ethanol group, isoforms gene expression changed and increased the reduced MAO levels and mitigated heart structural changes.

CONCLUSION

These findings indicate that ethanol-induced heart abnormalities may, in part, be associated with Ca2+ homeostasis changes mediated by overexpression of CaMKIIδ gene and the decrease of MAO levels and that these effects can be alleviated by using ginger extract as an antioxidant and anti-inflammatory agent.

A snapshot of the hepatic transcriptome: ad libitum alcohol intake suppresses expression of cholesterol synthesis genes in alcohol-preferring (P) rats

Research is uncovering the genetic and biochemical effects of consuming large quantities of alcohol. One prime example is the J- or U-shaped relationship between the levels of alcohol consumption and the risk of atherosclerotic cardiovascular disease. Moderate alcohol consumption in humans (about 30 g ethanol/d) is associated with reduced risk of coronary heart disease, while abstinence and heavier alcohol intake is linked to increased risk. However, the hepatic consequences of moderate alcohol drinking are largely unknown. Previous data from alcohol-preferring (P) rats showed that chronic consumption does not produce significant hepatic steatosis in this well-established model. Therefore, free-choice alcohol drinking in P rats may mimic low risk or nonhazardous drinking in humans, and chronic exposure in P animals can illuminate the molecular underpinnings of free-choice drinking in the liver. To address this gap, we captured the global, steady-state liver transcriptome following a 23 week free-choice, moderate alcohol consumption regimen (∼ 7.43 g ethanol/kg/day) in inbred alcohol-preferring (iP10a) rats. Chronic consumption led to down-regulation of nine genes in the cholesterol biosynthesis pathway, including HMG-CoA reductase, the rate-limiting step for cholesterol synthesis. These findings corroborate our phenotypic analyses, which indicate that this paradigm produced animals whose hepatic triglyceride levels, cholesterol levels and liver histology were indistinguishable from controls. These findings explain, at least in part, the J- or U-shaped relationship between cardiovascular risk and alcohol intake, and provide outstanding candidates for future studies aimed at understanding the mechanisms that underlie the salutary cardiovascular benefits of chronic low risk and nonhazardous alcohol intake.

Relation between alcohol consumption and arterial stiffness: A cross-sectional study of middle-aged Japanese women and men

Epidemiological data indicate the existence of a J-shaped association between alcohol consumption and cardiovascular mobility and mortality. However, studies assessing the relationship between alcohol consumption and pulse wave velocity (PWV) as a marker of arterial stiffness have provided inconsistent results. In addition, data regarding the effect of alcohol on arterial stiffness in women has been limited. This study aimed to clarify the relationship between alcohol consumption and PWV among female and male workers in Japan. Study participants were local government employees in Hokkaido, Japan, who underwent annual health check-ups. All data were collected using self-administered questionnaires. The average daily alcohol consumption of the previous month, based on the alcohol concentration of each beverage type (g/day, ethanol equivalent), was estimated according to the frequency and amount of consumption. Data from 3893 participants (812 women and 3081 men) were analyzed. In women, non-drinkers had significantly higher PWV than women who consumed <10 g/day of alcohol. In men, compared with those who reportedly drank 20-39 g/day, non-drinkers and those who drank <20 g/day and ≥60 g/day had significantly higher PWV. Alcohol consumption showed a J-shaped association with PWV in men (p for quadratic term < 0.036) and marginally in women (p < 0.056). The results of stratified analyses by age groups showed a significant J-shaped association, which was most notable for men ≥45 years (p < 0.005). In middle-aged Japanese women and men, light-to-moderate alcohol consumption is associated with lower PWV, which in turn correlates with a reduction in vascular stiffness.

Acute ethanol exposure increases the susceptibility of the donor hearts to ischemia/reperfusion injury after transplantation in rats

Background

Many donor organs come from youths involved in alcohol-related accidental death. The use of cardiac allografts for transplantation from donors after acute poisoning is still under discussion while acute ethanol intoxication is associated with myocardial functional and morphological changes. The aims of this work were 1) to evaluate in rats the time-course cardiac effects of acute ethanol-exposure and 2) to explore how its abuse by donors might affect recipients in cardiac pump function after transplantation.

Methods

Rats received saline or ethanol (3.45 g/kg, ip). We evaluated both the mechanical and electrical aspects of cardiac function 1 h, 6 h or 24 h after injection. Plasma cardiac troponin-T and glucose-levels were measured and histological examination of the myocardium was performed. In addition, heart transplantation was performed, in which donors received ethanol 6 h or 24 h prior to explantation. Graft function was measured 1 h or 24 h after transplantation. Myocardial TBARS-concentration was measured; mRNA and protein expression was assessed by quantitative real-time PCR and Western blot, respectively.

Results

Ethanol administration resulted in decreased load-dependent (−34±9%) and load-independent (−33±12%) contractility parameters, LV end-diastolic pressure and elevated blood glucose levels at 1 h, which were reversed to the level of controls after 6 h and 24 h. In contrast to systolic dysfunction, active relaxation and passive stiffness are slowly recovered or sustained during 24 h. Moreover, troponin-T-levels were increased at 1 h, 6 h and 24 h after ethanol injection. ST-segment elevation (+47±10%), elongated QT-interval (+38±4%), enlarged cardiomyocyte, DNA-strand breaks, increased both mRNA and protein levels of superoxide dismutase-1, glutathione peroxydase-4, cytochrome-c-oxidase and metalloproteinase-9 were observed 24 h following ethanol-exposure. After heart transplantation, decreased myocardial contractility and relaxation, oxidative stress and altered protein expression were observed.

Conclusions

These results demonstrate acute alcohol abuse increases the susceptibility of donor hearts to ischemia/reperfusion in a rat heart transplant model even though the global contractile function recovers 6 h after ethanol-administration.

Effects of ethanol intake on lipoproteins

These review discusses the effects of ethanol on lipoprotein levels and function as related to atherosclerosis and cardiovascular disease (CVD), with special emphasis on recent publications. Ethanol's effects on high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglycerides (TG), and other CVD risk factors recently have been explored. Other new data address genetic and demographic predictors and mechanisms of these responses. Not surprisingly, the results of some recent studies corroborate, whereas others differ from, earlier seemingly well-established findings. Prior and recent evidence shows favorable changes in HDL, other CVD risk factors, and CVD event rates with moderate, regular ethanol intake, and recent publications have explored the mechanisms of this relationship. Application of these findings in clinical practice remains problematic, however, due to the lack of randomized, controlled clinical trials of ethanol and due to the potential hazards of ethanol consumption.

Deficiency in AMPK attenuates ethanol-induced cardiac contractile dysfunction through inhibition of autophagosome formation

AIMS

Binge drinking often triggers compromised myocardial contractile function while activating AMP-activated protein kinase (AMPK). Given the role of AMPK in the initiation of autophagy through the mammalian target of rapamycin complex 1 (mTORC1) and Unc51-like kinase (ULK1), this study was designed to examine the impact of AMPK deficiency on cardiac function and the mechanism involved with a focus on autophagy following an acute ethanol challenge.

METHODS AND RESULTS

Wild-type (WT) and transgenic mice overexpressing a kinase-dead (KD) α2 isoform (K45R mutation) of AMPK were challenged with ethanol. Glucose tolerance, echocardiography, Langendorff heart and cardiomyocyte contractile function, autophagy, and autophagic signalling including AMPK, acetyl-CoA carboxylase (ACC), mTOR, the mTORC1-associated protein Raptor, and ULK1 were examined. Ethanol exposure triggered glucose intolerance and compromised cardiac contraction accompanied by increased phosphorylation of AMPK and ACC as well as autophagosome accumulation (increased LC3II and p62), the effects of which were attenuated or mitigated by AMPK deficiency or inhibition. Ethanol dampened and stimulated, respectively, the phosphorylation of mTOR and Raptor, the effects of which were abolished by AMPK deficiency. ULK1 phosphorylation at Ser(757) and Ser(777) was down-regulated and up-regulated, respectively, by ethanol, the effect of which was nullified by AMPK deficiency or inhibition. Moreover, the ethanol challenge enhanced LC3 puncta in H9c2 cells and promoted cardiac contractile dysfunction, and these effects were ablated by the inhibition of autophagy or AMPK. Lysosomal inhibition failed to accentuate ethanol-induced increases in LC3II and p62.

CONCLUSION

In summary, these data suggest that ethanol exposure may trigger myocardial dysfunction through a mechanism associated with AMPK-mTORC1-ULK1-mediated autophagy.

Adaptive changes in fatty acid profile of erythrocyte membrane in relation to plasma and red cell metabolic changes in chronic alcoholic men

Chronic alcohol consumption is a major reason for several human diseases, and alcoholism has been associated with a variety of societal problems. Changes in fatty acid metabolism in alcoholics and its effects leading to membrane damage are largely unknown. Therefore, we aimed to investigate the fatty acid composition of erythrocyte membrane phospholipids in relation with plasma lipid profile and other plasma metabolites in chronic alcoholics in comparison with controls. We systematically measured the levels of glucose, lactate and pyruvate in the blood and free amino acids, free fatty acids, mucoproteins and glycolipids, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein (VLDL) cholesterol and triglycerides (TG) in plasma of chronic alcoholics and controls. Furthermore, we measured fatty acid composition by gas chromatographic analysis. The fatty acid composition clearly revealed certain changes in chronic alcoholic erythrocyte membrane, chiefly increments in C16:0 and a decrease in C22:4 and C22:6 fatty acids besides the presence of unidentified fatty acids, probably C-24 or C-26 fatty acids. In addition, a significant increase in blood lactate, decrease in blood pyruvate and increased levels of free amino acids and free fatty acids, mucoproteins, VLDL cholesterol, TG and HDL-C in chronic alcoholics were observed with no significant change in plasma TC, LDL-C and glycolipids when compared with controls. Alcohol-induced alterations in plasma and erythrocyte membranes of chronic alcoholics in the present study might be an adaptive response to counteract the deleterious effects of alcohol. The implications of our findings warrant further investigation and needs further in-depth study to explore the mechanisms of alcohol-induced membrane changes.

Alcohol and the heart: an ounce of prevention

OPINION STATEMENT

Moderate alcohol intake is beneficial to the heart and cardiovascular system. A J- or U-shaped response has been shown in the majority of studies examining alcohol's effect on cardiovascular mortality and downstream cardio-metabolic effects, with heavy alcohol intake associated with worse outcomes. These effects apply to individuals with and without underlying coronary artery disease. However, care must be taken in defining "moderate" intake between the sexes. Males appear to have a wider therapeutic window and can afford 2 to 3 drinks per day whereas women should limit intake to 1 to 2 drinks per day (a "drink" being classified as 10 to 14 grams of alcohol). More than half of alcohol's cardioprotective effects can be attributed to its effect on lipoproteins, specifically an increase in high-density lipoprotein. Interestingly, the risk of cardiovascular mortality in former heavy drinkers has been shown to ultimately approach the risk seen in lifelong abstainers.

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.

Moderate alcohol intake, genital vascularization, and sexuality in young, healthy, eumenorrheic women. A pilot study

INTRODUCTION

The relationship between alcohol and sexual function is complex and not completely understood.

AIM

To evaluate (in the early follicular phase and independently from sexual stimulation) in young, eumenorrheic, healthy, lean women the genital vascular effects of the light and moderate use of alcohol.

METHODS

Eighty-four women undertook, in the early follicular phase of the menstrual cycle (days 3-5), the administration of the two-factor Italian McCoy Female Sexuality (MFSQ) and the Beck Depression Inventory (BDI) questionnaires; ultrasonographic measurement of the carotid intima-media thickness (IMT); and color Doppler evaluation of the carotid, clitoral, and labia minora arteries. Hormonal (estradiol, androstenedione, and testosterone) and biochemical (lipids, glucose, and insulin) parameters were tested.

MAIN OUTCOME MEASURES

The MFSQ and BDI questionnaires; the carotid IMT; the Pulsatility Index of internal carotid, clitoral, and labia minora arteries; blood pressure measurement; and hormonal and biochemical assays.

RESULTS

The subjects were divided in: nondrinkers (group I); current (>1 year) light drinkers--1-10 drinks/month (group II); and current moderate drinkers--11-20 drinks/month (group III). The majority of the studied parameters did not vary among the different groups. The mean BDI was normal in the studied women. However, the lowest values were observed in the moderate drinkers group. The MFSQ did not show any difference among all the studied women. However, the number of intercourses/week and the incidence of vaginal orgasm were significantly higher in group III (moderate drinkers). The relationship between the drinking habits and different parameters showed an inverse relationship with the BDI. Furthermore, the BDI inversely correlated with orgasm frequency and with orgasm intensity.

CONCLUSIONS

Chronic slight/moderate alcohol consumption has no effects on genital vessels and vaginal lubrication. However, a moderate consumption of alcohol, through psychological and social disinhibiting effects, may favor sexual activities.

Alcohol drinking, the metabolic syndrome and diabetes in a population with high mean alcohol consumption

AIMS

To investigate the relationship of alcohol consumption with the metabolic syndrome and diabetes in a population-based study with high mean alcohol consumption. Few data exist on these conditions in high-risk drinkers.

METHODS

In 6172 adults aged 35-75 years, alcohol consumption was categorized as 0, 1-6, 7-13, 14-20, 21-27, 28-34 and ≥ 35 drinks/week or as non-drinkers (0), low-risk (1-13), medium-to-high-risk (14-34) and very-high-risk (≥ 35) drinkers. Alcohol consumption was objectively confirmed by biochemical tests. In multivariate analysis, we assessed the relationship of alcohol consumption with adjusted prevalence of the metabolic syndrome, diabetes and insulin resistance, determined with the homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

Seventy-three per cent of participants consumed alcohol, 16% were medium-to-high-risk drinkers and 2% very-high-risk drinkers. In multivariate analysis, the prevalence of the metabolic syndrome, diabetes and mean HOMA-IR decreased with low-risk drinking and increased with high-risk drinking. Adjusted prevalence of the metabolic syndrome was 24% in non-drinkers, 19% in low-risk (P<0.001 vs. non-drinkers), 20% in medium-to-high-risk and 29% in very-high-risk drinkers (P=0.005 vs. low-risk). Adjusted prevalence of diabetes was 6.0% in non-drinkers, 3.6% in low-risk (P<0.001 vs. non-drinkers), 3.8% in medium-to-high-risk and 6.7% in very-high-risk drinkers (P=0.046 vs. low-risk). Adjusted HOMA-IR was 2.47 in non-drinkers, 2.14 in low-risk (P<0.001 vs. non-drinkers), 2.27 in medium-to-high-risk and 2.53 in very-high-risk drinkers (P=0.04 vs. low-risk). These relationships did not differ according to beverage types.

CONCLUSIONS

Alcohol has a U-shaped relationship with the metabolic syndrome, diabetes and HOMA-IR, without differences between beverage types.

Effects of ethanol intake on lipoproteins and atherosclerosis

PURPOSE OF REVIEW

This article reviews published studies regarding effects of ethanol intake on lipoprotein levels and function as they relate to atherosclerosis, with special emphasis on recent publications in the past 2 years.

RECENT FINDINGS

Some recent studies have explored novel mechanisms of ethanol on atherogenesis via effects on HDL composition and function. Other studies have focused on changes in levels of LDL cholesterol (LDL-C), triglyceride, and other factors such as inflammatory markers C-reactive protein (CRP) and lipoprotein-associated phospholipase A2 (LpPLA2). Other areas of emphasis have been the effects within specific populations and between genders, as well as contributions of genetic polymorphisms in prediction of response to ethanol. Surprisingly, results of recent studies are often at odds with prior, seemingly well established findings.

SUMMARY

The association between moderate ethanol consumption and favorable changes in lipoproteins and lipoprotein-related factors in atherosclerosis continues to become better established with the publication of new studies in this field. Continued progress is being achieved in understanding the well established link between moderate intake and reduced risk of cardiovascular disease (CVD). Nevertheless, it remains difficult to implement these findings in clinical practice due to the ongoing lack of randomized, blinded clinical trial data, and the well known hazards of excess ethanol consumption.

Aldehyde dehydrogenase 2 knockout accentuates ethanol-induced cardiac depression: role of protein phosphatases

Alcohol consumption leads to myocardial contractile dysfunction possibly due to the toxicity of ethanol and its major metabolite acetaldehyde. This study was designed to examine the influence of mitochondrial aldehyde dehydrogenase-2 (ALDH2) knockout (KO) on acute ethanol exposure-induced cardiomyocyte dysfunction. Wild-type (WT) and ALDH2 KO mice were subjected to acute ethanol (3g/kg, i.p.) challenge and cardiomyocyte contractile function was assessed 24h later using an IonOptix edge detection system. Western blot analysis was performed to evaluate ALDH2, protein phosphatase 2A (PP2A), phosphorylation of Akt, and glycogen synthase kinase-3beta (GSK-3beta). ALDH2 KO accentuated ethanol-induced elevation in cardiac acetaldehyde levels. Ethanol exposure depressed cardiomyocyte contractile function including decreased cell shortening amplitude and maximal velocity of shortening/relengthening as well as prolonged relengthening duration and a greater decline in peak shortening in response to increasing stimulus frequency, the effect of which was significantly exaggerated by ALDH2 KO. ALDH2 KO also unmasked an ethanol-induced prolongation of shortening duration. In addition, short-term in vitro incubation of ethanol-induced cardiomyocyte mechanical defects was exacerbated by the ALDH inhibitor cyanamide. Ethanol treatment dampened phosphorylation of Akt and GSK-3beta associated with upregulated PP2A, which was accentuated by ALDH2 KO. ALDH2 KO aggravated ethanol-induced decrease in mitochondrial membrane potential. These results suggested that ALDH2 deficiency led to worsened ethanol-induced cardiomyocyte function, possibly due to upregulated expression of protein phosphatase, depressed Akt activation, and subsequently impaired mitochondrial function. These findings depict a critical role of ALDH2 in the pathogenesis of alcoholic cardiomyopathy.

Age-dependent associations of smoking and drinking with non-high-density lipoprotein cholesterol

Serum high-density lipoprotein (HDL) cholesterol levels are influenced by habitual smoking and drinking. Non-HDL cholesterol is known to be a potent predictor of cardiovascular disease. However, it remains to be determined whether the associations of non-HDL cholesterol with smoking and drinking differ with age. The objectives of this study were to investigate relationships among smoking, drinking, and non-HDL cholesterol and to investigate interactions of age with smoking and drinking regarding serum non-HDL cholesterol levels. Subjects (54,020 Japanese men aged 20-69 years) were divided into drinkers and nondrinkers or into smokers and nonsmokers and were further divided into 5 age groups with 10-year intervals. Subjects in each age group were divided into 3 subgroups according to alcohol or cigarette consumption. The mean levels of serum non-HDL cholesterol calculated after adjustment for age and body mass index were compared among the groups. In nondrinkers, non-HDL cholesterol levels of subjects in their 40s or older were significantly higher in heavy smokers than in nonsmokers, whereas non-HDL cholesterol levels of subjects in their 20s and 30s were not significantly different among non-, light, and heavy smokers. In drinkers, non-HDL cholesterol levels of subjects in all age groups were not higher in light and heavy smokers than in nonsmokers. In nonsmokers, non-HDL cholesterol in subjects in their 30s or older was significantly lower in light and heavy drinkers than in nondrinkers, whereas this difference was not observed in subjects in their 20s. In smokers, non-HDL cholesterol levels of subjects in all age groups were significantly lower in light and heavy drinkers than in nondrinkers, and the differences in non-HDL cholesterol between drinkers and nondrinkers tended to increase with advance of age. The difference in non-HDL cholesterol between drinkers and nondrinkers tended to be greater in smokers than in nonsmokers. Thus, the associations of non-HDL cholesterol with smoking and drinking were modified by drinking and smoking, respectively. Smoking is associated with high non-HDL cholesterol in nondrinkers, and drinking is associated with low non-HDL cholesterol in nonsmokers; these associations are shown at middle and elderly ages but not at young ages.

Alcohol and acetaldehyde in public health: from marvel to menace

Alcohol abuse is a serious medical and social problem. Although light to moderate alcohol consumption is beneficial to cardiovascular health, heavy drinking often results in organ damage and social problems. In addition, genetic susceptibility to the effect of alcohol on cancer and coronary heart disease differs across the population. A number of mechanisms including direct the toxicity of ethanol, its metabolites [e.g., acetaldehyde and fatty acid ethyl esters (FAEEs)] and oxidative stress may mediate alcoholic complications. Acetaldehyde, the primary metabolic product of ethanol, is an important candidate toxin in developing alcoholic diseases. Meanwhile, free radicals produced during ethanol metabolism and FAEEs are also important triggers for alcoholic damages.

Influence of body weight on the relationships of alcohol drinking with blood pressure and serum lipids in women

OBJECTIVE

To determine whether body weight influences the associations of habitual alcohol drinking with blood pressure and serum lipids in women.

METHODS

The subjects were 16,805 healthy women at ages of 35-54 years, and data were collected at work places of the subjects in Yamagata Prefecture in Japan from April 1999 to March 2000. The subjects were divided into three tertile groups of body weight and were further divided into three subgroups by average ethanol intake [non-, light (<15 g per day), and heavy (> or =15 g per day) drinkers].

RESULTS

In the first and second tertile groups of body weight, mean systolic and diastolic blood pressure and prevalence of high systolic or diastolic blood pressure were significantly higher in heavy drinkers than in non-drinkers, while these differences were not observed in the third tertile group of body weight. On the other hand, in all tertile groups of body weight, mean serum HDL and LDL cholesterol levels were higher and lower, respectively, in light and heavy drinkers than in non-drinkers, and prevalence of low HDL cholesterol or high LDL cholesterol was significantly lower in heavy drinkers than in non-drinkers.

CONCLUSIONS

The results suggest that body weight influences the association of alcohol drinking with blood pressure but not the associations of alcohol drinking with serum HDL and LDL cholesterol.

Aldehyde dehydrogenase-2 transgene ameliorates chronic alcohol ingestion-induced apoptosis in cerebral cortex

Chronic intake of alcohol results in multiple organ damage including brain. This study was designed to examine the impact of facilitated acetaldehyde breakdown via transgenic overexpression of mitochondrial aldehyde dehydrogenase-2 (ALDH2) on alcohol-induced cerebral cortical injury. ALDH2 transgenic mice were produced using the chicken beta-actin promoter. Wild-type FVB and ALDH2 mice were placed on a 4% alcohol or control diet for 12 weeks. Protein damage and apoptosis were evaluated with carbonyl formation, caspase and TUNEL assays. Western blot was performed to examine expression (or its activation) of ALDH2, the pro- and anti-apoptotic proteins caspase-8, Bax, Bcl-2, Omi/HtrA2, apoptosis repressor with caspase recruitment domain (ARC), FLICE-like inhibitory protein (FLIP), X-linked inhibitor of apoptosis protein (XIAP), Akt, glycogen synthase kinase-3beta (GSK-3beta), p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). Chronic alcohol intake led to elevated apoptosis in the absence of overt protein damage, the effect of which was ablated by the overexpression of ALDH2 transgene. Consistently, ALDH2 transgene significantly attenuated alcohol-induced upregulation of Bax, Omi/HtrA2 and XIAP as well as downregulation of Bcl-2 and ARC without affecting alcohol-induced increase of FLIP in cerebral cortex. Phosphorylation of Akt and GSK-3beta was dampened while total/phosphorylated JNK and p38 phosphorylation were elevated following chronic alcohol intake, the effects of which were abrogated by ALDH2 transgene. Expression of total Akt, GSK-3beta, p38 and ERK (total or phosphorylated) was not affected by either chronic alcohol intake or ALDH2 transgene. Our results suggested that transgenic overexpression of ALDH2 rescues chronic alcoholism-elicited cerebral injury possibly via a mechanism associated with Akt, GSK-3beta, p38 and JNK signaling.

Influence of gender on the association of alcohol drinking with blood pressure

BACKGROUND

The purpose of this study was to determine whether gender influences the association of alcohol drinking with blood pressure.

METHODS

The subjects (43,810 healthy men and women at ages of 35-54 years) were divided into five groups by average daily ethanol intake (non-, very light (<10 g per day), light (> or =10 g and <20 g per day), moderate (> or =20 g and <30 g per day), and heavy (> or =30 g per day) drinkers). The means of each variable after adjustment for age, body weight, and history of smoking were compared among the groups.

RESULTS

Systolic blood pressure of men was significantly higher in moderate and heavy drinkers than in nondrinkers, and systolic blood pressure of women was significantly higher in heavy drinkers but not in moderate drinkers than in nondrinkers. Diastolic blood pressure of men and women was significantly higher in light, moderate and heavy drinkers than in nondrinkers. The differences in systolic and diastolic blood pressure between drinkers and nondrinkers were greater in men than in women. Both in men and women, serum HDL cholesterol was significantly higher in all four drinker groups than in the nondrinker group, and the difference between drinkers and nondrinkers was greater in women than in men. The above findings were not altered when age- and alcohol intake-matched groups of subjects were used.

CONCLUSIONS

The results suggest that blood pressure is more prone to be elevated by alcohol drinking in men than in women.

Mechanisms of alcoholic heart disease

Compromised heart function is regularly seen in patients with chronic alcohol ingestion and is often manifested as cardiomegaly, reduced myocardial contractility (with concomitant reductions in ejection fraction and stroke volume), myocardial fibrosis, enhanced risk of stroke and hypertension, and disruptions in the myofibrillary structure. A number of mechanisms including oxidative damage, deposition of triglycerides, altered fatty acid extraction, decreased myofilament Ca(2+) sensitivity, and impaired protein synthesis have been proposed for the development of alcoholic cardiomyopathy. Nonetheless, the underlying mechanism(s) has not been delineated. Several alcohol metabolites have been identified as specific toxins of myocardial tissue, including ethanol, its first and major metabolic product--acetaldehyde--and fatty acid ethyl esters. Acetaldehyde directly impairs cardiac contractile function, disrupts cardiac excitation-contraction coupling and promotes oxidative damage and lipid peroxidation. Unfortunately, the most direct approach to studying this (direct administration of acetaldehyde) is impossible, since direct intake of acetaldehyde is highly toxic and unsuitable for chronic studies. In order to overcome this obstacle, transgenic mice have recently been produced to artificially alter ethanol/acetaldehyde metabolism, resulting in elevated acetaldehyde levels after ethanol ingestion. This review will summarize some of the postulated mechanisms for alcoholic cardiomyopathy, with special emphasis on animal models.

The responses of mitochondrial proteome in rat liver to the consumption of moderate ethanol: the possible roles of aldo-keto reductases

A large body of evidence supports the view that mitochondria are a primary target of alcohol stress. Changes in mitochondrial proteins due to moderate ethanol intake, however, have not been broadly and accurately estimated. For this study, rats were fed low doses of ethanol and the mitochondria were isolated from heart, kidney, and liver, using ultracentrifugation with Nycodenz density gradient. The mitochondrial proteins were well resolved upon two-dimensional electrophoresis (2DE), and the alcohol-responsive 2DE spots were identified by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/TOF MS). Compared with the control group, the proteins extracted from liver mitochondria of ethanol-fed rats exhibited the significant changes on 2DE images, whereas the 2DE images obtained from the kidney and the heart mitochondria remained almost unchanged by ethanol feeding. Significantly, over 50% of the alcohol-responsive proteins in liver mitochondria were members of aldo-keto reductase family (AKR), which were usually present in cytoplasm. The organelle distributions of AKR proteins in liver mitochondria were further confirmed by Western blot analysis as well as by confocal microscopy. In addition, translocations of AKR were examined in the CHANG cell line, which was cultured with and without ethanol. The results of Western blot strongly suggested that the abundances of AKR proteins in the mitochondria were greatly reduced by the presence of ethanol in culture medium. The results of this study show that, even with moderate ethanol feeding, the mitochondrial proteome in rat liver was more sensitive to alcohol stress than that of either the kidney or the heart. The translocation of AKR proteins may be involved in the detoxification of liver cells.

Relationship of alcohol consumption and type of alcoholic beverage consumed with plasma lipid levels: differences between Whites and African Americans of the ARIC study

PURPOSE

Alcohol consumption has been shown to contribute to a favorable lipid profile, and most studies have reported a reduction in coronary heart disease risk with low-to-moderate consumption of alcohol that is generally attributed to the beneficial effects of alcohol on lipids. The influence of different types of alcoholic beverages on plasma lipid levels has been investigated to a lesser extent and in limited populations.

METHODS

We investigated the effect of overall alcohol consumption, as well as the type of alcoholic beverage consumed, on multiple lipid measures in the large bi-ethnic population of the Atherosclerosis Risk in Communities study.

RESULTS

We found both low-to-moderate and heavy alcohol consumption, regardless of the type of alcoholic beverage consumed, to result in significantly greater levels of high-density lipoprotein (HDL) cholesterol, HDL3 cholesterol, and apolipoprotein A-I in both white and African-American males and females. Associations with other lipid measures contrasted between whites and African Americans, with greater levels of alcohol consumption resulting in significantly greater triglyceride levels in African Americans.

CONCLUSIONS

Our results confirm previous studies associating alcohol consumption, regardless of beverage type, with greater HDL cholesterol levels, with additional consistent associations detected for the major HDL cholesterol density subfraction, HDL3 cholesterol, and the major HDL cholesterol structural apolipoprotein, apolipoprotein A-I.

Life style habits such as alcohol consumption and physical activity in relation to serum apoB / apoA-I ratio amongst 64-year-old women with varying degrees of glucose tolerance

OBJECTIVES

To investigate how life style factors such as alcohol consumption and physical activity relate to the serum apoB / apoA-I ratio in a cohort of middle-aged women with varying degrees of glucose tolerance.

DESIGN

Observational, cross-sectional cohort study.

SETTING

Research laboratory at a University Hospital.

SUBJECTS

A screened cohort of 64-year-old postmenopausal women with varying degrees of glucose tolerance, ranging from diabetes (n = 232), impaired (n = 212) and normal (n = 191) glucose tolerance.

MAIN OUTCOME MEASURE

ApoB / apoA-I ratio in relation to alcohol consumption and physical activity as assessed by questionnaires.

RESULTS

Alcohol consumption and regular physical activity at high levels were inversely associated with the serum apoB / apoA-I ratio independently of confounding factors such as obesity, lipid-lowering treatment, degree of glucose tolerance and hormone replacement therapy. Alcohol seemed related to the apoB / apoA-I ratio mainly through increasing apoA-I, whereas physical activity seemed mainly related to lowering of apoB. Alcohol consumption above a daily intake of 8.9 g, i.e. less than a glass of wine was accompanied by a decrease in apoB / apoA-I ratio.

CONCLUSIONS

Amongst these 64-year-old women with varying degrees of glucose tolerance, a moderate alcohol intake and regular physical exercise leading to sweating were associated with lower apoB / apoA-I ratio and these effects seem to be additive.

Ethanol stimulates bile acid formation in primary human hepatocytes

The conversion of cholesterol to bile acids is a key pathway for elimination of cholesterol from the body, thereby reducing the risk of arteriosclerosis. Moderate consumption of ethanol has been shown to have preventive effects on cardiovascular disease and decrease the risk of gallstone formation. In the present study primary human hepatocytes were used to investigate if ethanol affected bile acid synthesis. Hepatocytes were prepared from donor liver (n=11) and treated with ethanol, 7.7 or 50 mM, for 24 h. mRNA levels for enzymes in bile acid synthesis pathways were studied and bile acid synthesis was analyzed. Treatment with 7.7 mM ethanol increased cholic acid synthesis by 20% and treatment with 50 mM ethanol up-regulated cholic acid formation by 60%. The synthesis of cholic acid increased more than that of chenodeoxycholic acid, indicating that the classical pathway for bile acid synthesis was up-regulated. Increased bile acid levels in the cells treated with ethanol were seen after approximately 20 h. mRNA expression of CYP7A1, CYP27A1, and CYP8B1 in the hepatocytes was not affected by alcohol exposure.

Cholesterol homeostasis in the developing brain: a possible new target for ethanol

Cholesterol is an essential component of cell membranes and plays an important role in signal transduction. This brief overview presents evidence from the literature that ethanol may affect cholesterol homeostasis and that, in the developing brain, this may be involved in its developmental neurotoxicity. The effects caused by inborn errors of cholesterol synthesis and by in utero ethanol exposure present several similarities in humans (eg, Smith-Lemli-Opitz syndrome and fetal alcohol syndrome), as well as in animal models. Ethanol has a cholesterol-reducing effect on the cardiovascular system, and a protective effect against Alzheimer's disease, whose pathogenesis has been linked to altered cholesterol homeostasis in the brain. In vitro, ethanol affects several functions that are mediated by cholesterol and important for brain development, such as glial cell proliferation, synaptogenesis, neuronal survival and neurite outgrowth. The brain contains high levels of cholesterol, mostly synthesized in situ. Astrocytes produce large amounts of cholesterol that can be released by these cells and utilized by neurons to form synapses. Ethanol up-regulates the cholesterol transporter ATP binding cassette A1 and cholesterol efflux from primary astrocyte cultures without affecting cholesterol synthesis.

Interaction effects of high-density lipoprotein metabolism gene variation and alcohol consumption on coronary heart disease risk: the atherosclerosis risk in communities study

OBJECTIVE

Light to moderate alcohol consumption has been widely established to be protective against coronary heart disease (CHD), whereas heavy alcohol consumption has been shown to have a potential detrimental effect. The reduction in risk of CHD associated with light and moderate alcohol intake is generally attributed to the beneficial effects of alcohol on high-density lipoprotein (HDL) cholesterol levels. Previous research in the Atherosclerosis Risk in Communities (ARIC) study showed all levels of alcohol consumption to be protective against CHD in whites but to be associated with an increased risk of CHD in black men. We investigated the ARIC cohort to determine whether risk of incident CHD is influenced by an interaction effect between alcohol intake and genetic variation involved in the regulation of HDL cholesterol. Genes of interest included cholesterol ester transfer protein (CETP), lipoprotein lipase (LPL), hepatic lipase (HL), and paraoxonase-1 (PON1).

METHOD

Participants were selected from the ARIC study, a prospective investigation of atherosclerosis and its clinical sequelae, involving 15,792 individuals, ages 45-64 years at recruitment (1987-1989). Incident CHD was identified through annual telephone calls and hospital and death certificate surveillance. Because of ethnic differences in the alcohol-CHD relationship observed in the ARIC cohort and pattern of alcohol consumption differences, statistical analyses were evaluated separately for each race-gender stratum (white men/women, black men/women).

RESULTS

Genotype modified the relationship between heavy drinking and CHD risk but did not modify this relationship for light or moderate drinking. Interaction analyses were significant for heavy alcohol intake and PON1 genotype (p=.02) in black men, with a suggested interaction for heavy alcohol intake and CETP genotype (p=.06) in black men. Heavy drinking was associated with an increased risk for CHD in black men with the PON1 QQ and CETP GG genotypes (PON1 hazard rate ratio [HRR]=17.3, 95% confidence interval [CI]: 1.76-170.2; CETP HRR=2.23, 95% CI: 1.01-4.91).

CONCLUSIONS

Results from the current study suggest that interaction effects between alcohol consumption and HDL cholesterol metabolism gene variation influence the risk of incident CHD in black men. Additional studies are warranted to confirm these findings.

Chronic alcohol consumption alters mammalian target of rapamycin (mTOR), reduces ribosomal p70s6 kinase and p4E-BP1 levels in mouse cerebral cortex

Reduced insulin sensitivity following chronic alcohol consumption may contribute to alcohol-induced brain damage although the underlying mechanism(s) has not been elucidated. This study was designed to examine the effect of chronic alcohol intake on insulin signaling in mouse cerebral cortex. FVB mice were fed with a 4% alcohol diet for 16 weeks. Insulin receptor substrates (IRS-1, IRS-2) and post-receptor signaling molecules Akt, mammalian target of rapamycin (mTOR), ribosomal p70s6 kinase (p70s6k) and the eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) as well as the apoptotic marker caspase-3 were evaluated using Western blot analysis. Chronic alcohol intake significantly dampened whole body glucose tolerance, enhanced expression of caspase-3 and mTOR, reduced p70s6k and 4E-BP1 with little effect on Akt signaling in alcohol-consuming mice. These data suggest that chronic alcohol intake may contribute to cerebral cortex dysfunction through mechanisms related, at least in part, to dampened post insulin receptor signaling at the levels of mTOR, p70s6k and 4E-BP1.

Biochemical markers of alcoholism

Alcohol and alcohol-related diseases have become a major cause of death in Western countries. The most sensitive and specific of the commonly used biomarkers of alcohol intake are carbohydrate-deficient transferrin (CDT), and the combination of gamma-glutamyltransferase (GGT) and CDT. Other widely used laboratory markers are GGT, mean corpuscular volume of erythrocytes and the ratio of aspartate aminotransferase to alanine aminotransferase. Blood ethanol levels reveal recent alcohol use. However, more specific and sensitive biomarkers to improve the detection of excessive alcohol use at an early stage are needed. New biomarkers, not yet used in routine clinical work, include phosphatidylethanol, fatty acid ethyl esters, ethyl glucuronide, sialic acid, and acetaldehyde adducts.

CARDIAC OVEREXPRESSION OF METALLOTHIONEIN RESCUES CHRONIC ALCOHOL INTAKE-INDUCED CARDIOMYOCYTE DYSFUNCTION: ROLE OF AKT, MAMMALIAN TARGET OF RAPAMYCIN AND RIBOSOMAL P70S6 KINASE

AIMS

Reduced insulin sensitivity following alcohol intake plays a role in alcohol-induced organ damage although its precise mechanism is undefined. This study was designed to examine the effect of cardiac overexpression of the antioxidant metallothionein on alcohol-induced cardiac contractile dysfunction and post-receptor insulin signaling.

METHODS

FVB and metallothionein mice were fed a 4% alcohol diet for 16 weeks. Cardiomyocyte contractile function was evaluated including peak shortening (PS), time-to-PS (TPS), and time-to-relengthening (TR(90)). Post-insulin receptor signaling molecules Akt, mammalian target of rapamycin (mTOR), and ribosomal p70s6 kinase (p70s6k) were evaluated using western blot analysis. Akt1 kinase activity was assayed with a phosphotransferase kit.

RESULTS

Alcohol intake dampened whole body glucose tolerance, depressed PS, shortened TPS, and prolonged TR(90), which were abrogated by metallothionein with the exception of glucose intolerance. Our results revealed reduced expression of total Akt, phosphorylated mTOR, and phosphorylated p70s6k-to-p70s6k ratio as well as Akt1 kinase activity in alcohol consuming FVB mice. Phosphorylated Akt, total mTOR, and phosphorylated p70s6k were unaffected by alcohol. Metallothionein ablated reduced Akt protein and kinase activity without affecting any other proteins or their phosphorylation.

CONCLUSION

In summary, our data suggest that chronic alcohol intake interrupted cardiac contractile function and Akt/mTOR/p70s6k signaling. Akt but unlikely mTOR and p70s6k may contribute to metallothionein-elicited cardiac protective response.

Serum Lipids and Risk Factors for Attempted Suicide in Patients with Alcohol Dependence

BACKGROUND

Alcohol dependence is a major risk factor for suicidal behavior. Although a number of risk factors have been suggested there is still no well-defined risk profile for attempted suicide in alcoholic patients. Alterations of serum lipids have been associated with completed as well as attempted suicide and with suicidal ideation. This study investigated potential demographic and clinical risk factors for attempted suicide in alcohol-dependent patients taking serum lipids additionally into consideration.

METHODS

One-hundred ten alcohol-dependent patients who were admitted to a psychiatric university hospital department for inpatient treatment were grouped according to whether or not they had a lifetime history of attempted suicide. Attempters versus nonattempters as well as attempters who used a violent versus a nonviolent suicide method were compared.

RESULTS

Patients who had attempted suicide at least once in their life differed significantly from those who had no history of suicide attempts. Univariate analyses showed that they were younger (41.7 years vs 46.8 years; p = 0.003), were more often smokers (97% vs 77%; p = 0.011), had more frequently coabused benzodiazepines (54% vs 17%; p = 0.002), and scored currently higher on the Montgomery and Asberg Depression Rating Scale (MADRS) global scale (26.3 vs 20.2; p = 0.005) as well as the "suicidal thoughts" item (1.8 vs 0.6; p = 0.001). Additionally, they had higher serum triglyceride levels (178.9 vs 127.5; p = 0.039). A logistic regression analysis left coabuse of benzodiazepines [odds ratio (OR), 5.26; p = 0.001], younger age (OR per year increase of age, 0.91; p = 0.006), and current MADRS item 10 ("suicidal thoughts") score (OR per point increase in MADRS item 10 score, 1.43; p = 0.019) as significant factors. Suicide attempters who had used a violent method were significantly more often male (82% vs 44%; p = 0.035), were younger (38.2% vs 45.1 years; p = 0.008), and had less frequently coabused tranquilizers (35% vs 78%; p = 0.018) than nonviolent attempters.

CONCLUSIONS

These findings contribute to the development of a more specific profile of alcohol-dependent individuals at risk for suicidal behavior. Further research is required to determine the role of serum triglycerides for suicidal behavior in patients with alcohol dependence.

Effects of ethanol on lipids and atherosclerosis

Moderate alcohol consumption is associated with an increase in plasma high density lipoprotein (HDL) cholesterol concentration and a decrease in low density lipoprotein (LDL) cholesterol concentration. Changes in the concentration and composition of lipoproteins are estimated to account for more than half of alcohol's protective effect for coronary heart disease. Alcohol intake also affects plasma proteins involved in lipoprotein metabolism: cholesteryl ester transfer protein, phospholipid transfer protein, lecithin:cholesterol acyltransferase, lipoprotein lipase, hepatic lipase, and phospholipases. In addition, alcohol intake may result in acetaldehyde modification of apolipoproteins. Furthermore, "abnormal" lipids, phosphatidylethanol and fatty acid ethyl esters are formed in the presence of ethanol and are associated with lipoproteins in plasma. Ethanol and ethanol-induced modifications of lipids may modulate the effects of lipoproteins on the cells in the arterial wall. The molecular mechanisms involved in these processes are complex, requiring further study to better understand the specific effects of ethanol in the pathogenesis of atherosclerosis. This review discusses the effects of ethanol on lipoproteins and lipoprotein metabolism, as well as the novel effects of lipoproteins on vascular wall cells.