Effect of moderate alcohol consumption on adiponectin, tumor necrosis factor-alpha, and insulin sensitivity

Alcohol Consumption and Cardiovascular Disease: A Narrative Review of Evolving Perspectives and Long-Term Implications

Cardiovascular illnesses remain the primary cause of death, accounting for at least 17.9 million fatalities per year and posing a significant public health problem because of its extensive predominance and effect on healthcare systems. The etiology of cardiovascular disease is complex and involves several environmental and lifestyle factors. Alcohol use is a highly important determinant because of its dual-edged effect on cardiovascular health. Multiple studies indicate that moderate alcohol consumption may have certain advantages, such as slight enhancements in lipid profiles. Conversely, excessive alcohol intake is associated with serious negative consequences, including cardiomyopathy, hypertension, arrhythmias, and even mortality. The aim of this study is to provide a comprehensive analysis of the several effects of alcohol on cardiovascular health and their understanding within the medical field over time. It uses an interpretative narrative review methodology and analyzes studies that focus on genetic risk factors, gender differences, and shifts in paradigms in recent years. This article highlights the need for obtaining a thorough understanding of the effects of alcohol on cardiovascular health to support public health guidelines and clinical practice, and it underscores the significance of including alcohol consumption into the broader context of cardiovascular risk management and identifies important subjects for further study.

Is There a Safe Alcohol Consumption Limit for the General Population and in Patients with Liver Disease?

Excessive alcohol consumption represents an important burden for health systems worldwide and is a major cause of liver- and cancer-related deaths. Alcohol consumption is mostly assessed by self-report that often underestimates the amount of drinking. While alcohol use disorders identification test - version C is the most widely used test for alcohol use screening, in patients with liver disease the use of alcohol biomarker could help an objective assessment. The amount of alcohol that leads to significant liver disease depends on gender, genetic background, and coexistence of comorbidities (i.e., metabolic syndrome factors). All patients with alcohol-associated liver disease are recommended to follow complete abstinence and they should be treated within multidisciplinary teams. Abstinence slows down and even reverses the progression of liver fibrosis and can help recompensate patients with complicated cirrhosis. Whether there is a safe amount of alcohol in the general population is a matter of intense debate. Large epidemiological studies showed that the safe amount of alcohol to avoid overall health-related risks is lower than expected even in the general population. Even one drink per day can increase cancer-related death. In patients with any kind of chronic liver disease, especially in those with metabolic-associated steatotic liver disease, no alcohol intake is recommended. This review article discusses the current evidence supporting the deleterious effects of small-to-moderate amounts of alcohol in the general population and in patients with underlying chronic liver disease.

Novel paradigms for the gut-brain axis during alcohol withdrawal, withdrawal-associated depression, and craving in patients with alcohol use disorder

Introduction

Patients with alcohol use disorder (AUD) exhibit symptoms such as alcohol withdrawal, depression, and cravings. The gut-immune response may play a significant role in manifesting these specific symptoms associated with AUD. This study examined the role of gut dysfunction, proinflammatory cytokines, and hormones in characterizing AUD symptoms.

Methods

Forty-eight AUD patients [men (n = 34) and women (n = 14)] aged 23-63 years were grouped using the Clinical Institute Withdrawal Assessment of Alcohol Scale (CIWA) as clinically significant (CS-CIWA [score > 10] [n = 22]) and a clinically not-significant group (NCS-CIWA [score ≤ 10] [n = 26]). Clinical data (CIWA, 90-day timeline followback [TLFB90], and lifetime drinking history [LTDH]) and blood samples (for testing proinflammatory cytokines, hormones, and markers of intestinal permeability) were analyzed. A subset of 16 AUD patients was assessed upon admission for their craving tendencies related to drug-seeking behavior using the Penn-Alcohol Craving Score (PACS).

Results

CS-CIWA group patients exhibited unique and significantly higher levels of adiponectin and interleukin (IL)-6 compared to NCS-CIWA. In the CS group, there were significant and high effects of association for the withdrawal score with gut-immune markers (lipopolysaccharide [LPS], adiponectin, IL-6, and IL-8) and for withdrawal-associated depression with gut-immune markers (scored using MADRS with LPS, soluble cells of differentiation type 14 [sCD14], IL-6, and IL-8). Craving (assessed by PACS, the Penn-Alcohol Craving Scale) was significantly characterized by what could be described as gut dysregulation (LBP [lipopolysaccharide binding protein] and leptin) and candidate proinflammatory (IL-1β and TNF-α) markers. Such a pathway model describes the heavy drinking phenotype, HDD90 (heavy drinking days past 90 days), with even higher effects (R2 = 0.955, p = 0.006) in the AUD patients, who had higher ratings for cravings (PACS > 5).

Discussion

The interaction of gut dysfunction cytokines involved in both inflammation and mediating activity constitutes a novel pathophysiological gut-brain axis for withdrawal symptoms and withdrawal-associated depression and craving symptoms in AUD. AUD patients with reported cravings show a significant characterization of the gut-brain axis response to heavy drinking.

Trial registration

ClinicalTrials.gov, identifier: NCT# 00106106.

You are What You Drink? How Associations Between Profiles of Beverage Consumption and Type 2 Diabetes Risk are Mediated by Biomarker Networks

BACKGROUND

Multiple studies have independently investigated the associations of the consumption of individual beverage types and specific plasma biomarkers with the risk of type 2 diabetes (T2D). However, as individuals do not consume single beverage types exclusively and plasma biomarkers do not act in isolation, it remains unclear how patterns of beverage consumption and plasma biomarker networks associate both with each other and T2D risk.

OBJECTIVES

We aimed to elucidate potential dietary determinants of T2D risk by defining a model that describes habitual beverage consumption profiles in relation to identified networks of circulating plasma biomarkers.

METHODS

This study included 1,461 case and 1,568 control participants from case-control studies of T2D nested within the Nurses' Health Study. Participants completed validated semiquantitative food frequency questionnaires that assessed habitual beverage consumption, and they provided blood samples from which 27 plasma biomarkers of cardiometabolic risk were identified. Common exploratory factor analysis (EFA) identified factors that separately described beverage consumption profiles and biomarker networks. Multivariable-adjusted regression elucidated the relationships between beverage and biomarker factors and T2D risk.

RESULTS

EFA revealed five factors describing unique beverage consumption profiles and seven factors describing biomarker networks. The factor describing alcoholic beverage consumption was associated with a reduced risk of T2D (odds ratio [OR]: 0.50 [0.40, 0.64], P<0.001) mediated, in part, by the factor describing increased concentrations of adiponectin biomarkers (19.9% [12.0, 31.1] P = 0.004). The factor describing low-calorie sweetened beverage (LCSBs) consumption was associated with an increased risk of T2D (OR: 1.33 [1.03, 1.72], P = 0.021), and the factor describing lower concentrations of insulin-like growth factor binding proteins 1 and 2, and soluble leptin receptor, and increased leptin concentrations (P = 0.005).

CONCLUSIONS

Moderate alcohol consumption was associated with reduced T2D risk, mediated in part by increased circulating adiponectin. LCSB consumption was associated with both increased T2D risk and perturbed insulin-like growth factor and leptin signaling.

Associations between alcohol and cigarette use and type 1 and 2 myocardial infarction among people with HIV

OBJECTIVES

People with HIV have a higher risk of myocardial infarction (MI) than the general population, with a greater proportion of type 2 MI (T2MI) due to oxygen demand-supply mismatch compared with type 1 (T1MI) resulting from atherothrombotic plaque disruption. People living with HIV report a greater prevalence of cigarette and alcohol use than do the general population. Alcohol use and smoking as risk factors for MI by type are not well studied among people living with HIV. We examined longitudinal associations between smoking and alcohol use patterns and MI by type among people living with HIV.

DESIGN AND METHODS

Using longitudinal data from the Centers for AIDS Research Network of Integrated Clinical Systems cohort, we conducted time-updated Cox proportional hazards models to determine the impact of smoking and alcohol consumption on adjudicated T1MI and T2MI.

RESULTS

Among 13 506 people living with HIV, with a median 4 years of follow-up, we observed 177 T1MI and 141 T2MI. Current smoking was associated with a 60% increase in risk of both T1MI and T2MI. In addition, every cigarette smoked per day was associated with a 4% increase in risk of T1MI, with a suggestive, but not significant, 2% increase for T2MI. Cigarette use had a greater impact on T1MI for men than for women and on T2MI for women than for men. Increasing alcohol use was associated with a lower risk of T1MI but not T2MI. Frequency of heavy episodic alcohol use was not associated with MI.

CONCLUSIONS

Our findings reinforce the prioritization of smoking reduction, even without cessation, and cessation among people living with HIV for MI prevention and highlight the different impacts on MI type by gender.

Moderate alcohol drinking with meals is related to lower incidence of type 2 diabetes

BACKGROUND

Previous studies on alcohol drinking and health largely have ignored the potential impact of the timing of drinking.

OBJECTIVES

We aimed to investigate the joint associations of the timing of alcohol intake with respect to meals (i.e., with meals or outside of meals) and the amount of alcohol consumed with the risk of type 2 diabetes (T2D).

METHODS

A total of 312,388 current drinkers from the UK Biobank without T2D at baseline were included. Cox proportional hazards models were used to examine the association between the timing of alcohol intake with respect to meals and the risk of T2D.

RESULTS

During a median of 10.9 y of follow-up, 8598 incident cases of T2D were documented. After adjustment for covariates and the amount of alcohol consumed, consuming alcohol with meals was significantly associated with a 12% lower risk of T2D (HR: 0.88; 95% CI: 0.83, 0.93) than was consuming alcohol outside of meals. In addition, we found that the timing of alcohol intake with respect to meals significantly modified the relations between the amount of alcohol consumed and risk of T2D (P-interaction = 0.017); the beneficial association of moderate drinking with T2D risk was only observed in participants who consumed alcohol with meals, but not in others. Further analyses on various types of alcoholic beverages indicated that the beneficial associations between alcohol drinking with meals and T2D were mainly driven by wine consumption. Moreover, we found that when consumed together with meals, drinking more wine, rather than other alcoholic beverages, was related to lower concentrations of C-reactive protein.

CONCLUSIONS

In current drinkers, moderate drinking of alcohol, especially wine, with meals is associated with a lower risk of T2D.

Prospective Association of Circulating Adipokines with Cardiometabolic Risk Profile Among Women: The Rape Impact Cohort Evaluation Study

BACKGROUND

Sexual violence is associated with poor cardiometabolic outcomes, yet the etiopathogenic pathways remain unclear. Adipokines may contribute to pathways in the development of cardiometabolic disease (CMD), including in vulnerable populations. Further investigation of adipokines among sexually traumatized individuals may inform cardiometabolic screening. This study aimed to investigate the association between circulating adipokines, metabolic syndrome (MetS), and longitudinal change in MetS components (namely abdominal obesity, blood pressure, lipid profile, and glycemic status) over a 1-year period in a cohort of rape exposed (RE) and rape unexposed (RUE) females.

MATERIALS AND METHODS

Seven hundred seventy-eight RE and 617 RUE black South African women aged 18-40 years were recruited for the Rape Impact Cohort Evaluation study. Nonfasting blood samples were analyzed for cardiometabolic variables and adipokine levels using enzyme-linked immunosorbent assay. Serum adiponectin was measured in both RE and RUE and resistin, leptin, and leptin/adiponectin (L/A) ratio in RE only. Associations between baseline serum adipokines, MetS, and its components were assessed at baseline and follow-up using adjusted linear and logistic regressions.

RESULTS

In the RE group, adiponectin, leptin, and L/A ratio were significantly associated with MetS prevalence cross-sectionally (all p ≤ 0.001). No adipokine marker was related to incident MetS at 12-month follow-up. In the RE group, significant longitudinal associations with high-density lipoprotein cholesterol were shown for adiponectin (β = 0.146 [0.064], p = 0.022) and leptin (β = 0.001 [0.002], p = 0.012).

CONCLUSIONS

Findings suggest that adipokines may have a potential role as biomarkers to identify RE individuals at high risk for CMD.

Association of alcohol drinking with incident type 2 diabetes and pre-diabetes: The Guangzhou Biobank Cohort Study

AIMS

We examined associations of baseline alcohol drinking with incident type 2 diabetes (T2D) or impaired fasting glucose (IFG), and explore whether the associations were modified by genetic polymorphisms of aldehyde dehydrogenase-2 (ALDH2) and alcohol dehydrogenase-1B (ADH1B).

MATERIALS AND METHODS

All participants were aged 50+ (mean = 60.45; standard deviation = 6.88) years. Information of alcohol consumption was collected at baseline from 2003 to 2008. Incident T2D was defined as fasting glucose ≥7.0 mmol/L or post-load glucose ≥11.1 mmol/L at follow-up examination (2008-2012), self-reported T2D and/or initiation of hypoglycaemia medication or insulin during follow-up. Impaired fasting glucose was defined as fasting glucose ≥5.6 mmol/L and <7 mmol/L.

RESULTS

Of 15,716 participants without diabetes and 11,232 participants without diabetes and IFG at baseline, 1624 (10.33%) developed incident T2D and 1004 (8.94%) developed incident IFG during an average 4 years of follow-up. After multivariable adjustments, compared with never drinking, occasional or moderate alcohol drinking was not associated with risk of incident hyperglycaemia (T2D + IFG) (odds ratio (OR) = 1.10, 95% confidence interval (CI) 0.95-1.27, and 0.90 (0.69-1.18), respectively), whereas heavy alcohol drinking was associated with a higher risk of incident hyperglycaemia (T2D + IFG) (OR = 1.82, 95% CI 1.24-2.68). No interactions of sex, overweight/obesity and genetic polymorphisms of ADH1B/ALDH2 genes with alcohol drinking on incident T2D and/or IFG were found (P for interaction from 0.12 to 0.85).

CONCLUSIONS

Our results support a detrimental effect of heavy alcohol use on IFG and T2D. No protective effect was found for those carrying lower risk alleles for ADH1B/ALDH2 genes.

Gut Microbiota: Target for Modulation of Gut-Liver-Adipose Tissue Axis in Ethanol-Induced Liver Disease

Consumption of alcohol (ethanol) in various forms has been an integral part of human civilization. Since ages, it also has been an important cause of death and health impairment across the globe. Ethanol-mediated liver injury, known as alcoholic liver disease (ALD), is caused by surplus intake of alcohol. Several studies have proposed the different pathways that may be lead to ALD. One of the factors that may affect the cytochrome P450 (CYP2E1) metabolic pathway is gut dysbiosis. The gut microbiota produces various compounds that play an important role in regulating healthy functions of distal organs such as the adipose tissue and liver. Dysbiosis causes bacteremia, hepatic encephalopathy, and increased intestinal permeability. Recent clinical studies have found better understanding of the gut and liver axis. Another factor that may affect the ALD pathway is dysfunction of adipose tissue metabolism. Moreover, dysfunction of adipose tissue leads to ectopic fat deposition within the liver and disturbs lipid metabolism by increasing lipolysis/decreasing lipogenesis and impaired glucose tolerance of adipose tissue which leads to ectopic fat deposition within the liver. Adipokine secretion of resistin, leptin, and adiponectin is adversely modified upon prolonged alcohol consumption. In the combination of these two factors, a proinflammatory state is developed within the patient leading to the progression of ALD. Thus, the therapeutic approach for treatments and prevention for liver cirrhosis patients must be focused on the gut-liver-adipose tissue network modification with the use of probiotics, synbiotics, and prebiotics. This review is aimed at the effect of ethanol on gut and adipose tissue in both rodent and human alcoholic models.

Prevalence of metabolic syndrome and its related factors among Vietnamese people: A systematic review and meta-analysis

BACKGROUND AND AIMS

Metabolic risk factors are the leading causes of mortality and morbidity in recent decades, yet the burden of metabolic syndrome (MetS) has not been carefully assessed in Vietnam. This review thus aims to examine the prevalence of MetS and its related factors in Vietnam.

METHODS

A systematic review was conducted using literature retrieved from PubMed/Medline, Web of Science, Embase, Scopus, and Google Scholar up until July 2021. We selected descriptive and analytical studies which reported the prevalence of MetS and related factors among healthy people aged less than 65 years old rather than morbid people in Vietnam. A meta-analysis with a random-effects model was applied to estimate the pooled prevalence from the included studies.

RESULTS

Eighteen studies with 35421 participants were included in the final analysis. The pooled MetS prevalence among the adult population in Vietnam was 16.1% (95% Confidence Interval (CI): 14.1%-18.1%). Higher prevalence was seen among females (17.3%, 95% CI: 13.8%-20.8%). Low level of High Density Lipoprotein-Cholesterol (HDL-C) was the most prevalent component (34.1%), followed by high triglycerides (33.3%). Being female, living in urban areas, having obesity, and having a higher body mass index or body fat percentage were associated with an increased likelihood of having MetS.

CONCLUSIONS

MetS was common in the Vietnamese population. Low HDL-C should be considered as an early detectable indicator for MetS screening programs at the population level. Appropriate interventions should be conducted for high-risk groups such as females, those living in urban areas, and obesity.

Alcohol and Metabolic-associated Fatty Liver Disease

The diagnosis of metabolic-associated fatty liver disease is based on the detection of liver steatosis together with the presence of metabolic dysfunction. According to this new definition, the diagnosis of metabolic-associated fatty liver disease is independent of the amount of alcohol consumed. Actually, alcohol and its metabolites have various effects on metabolic-associated abnormalities during the process of alcohol metabolism. Studies have shown improved metabolic function in light to moderate alcohol drinkers. There are several studies focusing on the role of light to moderate alcohol intake on metabolic dysfunction. However, the results from studies are diverse, and the conclusions are often controversial. This review systematically discusses the effects of alcohol consumption, focusing on light to moderate alcohol consumption, obesity, lipid and glucose metabolism, and blood pressure.

A review of the role of ethanol-induced adipose tissue dysfunction in alcohol-associated liver disease

Alcohol-associated liver disease (AALD) encompasses a spectrum of liver diseases that includes simple steatosis, steatohepatitis, fibrosis, and cirrhosis. The adverse effects of alcohol in liver and the mechanisms by which ethanol (EtOH) promotes liver injury are well studied. Although liver is known to be the primary organ affected by EtOH exposure, alcohol's effects on other organs are also known to contribute significantly to the development of liver injury. It is becoming increasingly evident that adipose tissue (AT) is an important site of EtOH action. Both AT storage and secretory functions are altered by EtOH. For example, AT lipolysis, stimulated by EtOH, contributes to chronic alcohol-induced hepatic steatosis. Adipocytes secrete a wide variety of biologically active molecules known as adipokines. EtOH alters the secretion of these adipokines from AT, which include cytokines and chemokines that exert paracrine effects in liver. In addition, the level of EtOH-metabolizing enzymes, in particular, CYP2E1, rises in the AT of EtOH-fed mice, which promotes oxidative stress and/or inflammation in AT. Thus, AT dysfunction characterized by increased AT lipolysis and free fatty acid mobilization and altered secretion of adipokines can contribute to the severity of AALD. Of note, moderate EtOH exposure results in AT browning and activation of brown adipose tissue which, in turn, can promote thermogenesis. In this review article, we discuss the direct effects of EtOH consumption in AT and the mechanisms by which EtOH impacts the functions of AT, which, in turn, increases the severity of AALD in animal models and humans.

Insulin Resistance as a Common Link Between Current Alzheimer's Disease Hypotheses

Almost 115 years ago, Alois Alzheimer described Alzheimer's disease (AD) for the first time. Since then, many hypotheses have been proposed. However, AD remains a severe health public problem. The current medical approaches for AD are limited to symptomatic interventions and the complexity of this disease has led to a failure rate of approximately 99.6%in AD clinical trials. In fact, no new drug has been approved for AD treatment since 2003. These failures indicate that we are failing in mimicking this disease in experimental models. Although most studies have focused on the amyloid cascade hypothesis of AD, the literature has made clear that AD is rather a multifactorial disorder. Therefore, the persistence in a single theory has resulted in lost opportunities. In this review, we aim to present the striking points of the long scientific path followed since the description of the first AD case and the main AD hypotheses discussed over the last decades. We also propose insulin resistance as a common link between many other hypotheses.

Moderate alcohol consumption is associated with impaired insulin secretion and fasting glucose in non-obese non-diabetic men

AIMS/INTRODUCTION

A low insulin secretion capacity has been implicated in the high prevalence of non-obese diabetes in East Asians. As alcohol consumption alters insulin and glucose metabolism, we tested the hypothesis that alcohol consumption contributes to impaired insulin secretion and glucose intolerance in lean/normal-weight non-diabetic Japanese men.

MATERIALS AND METHODS

This cross-sectional study was undertaken among the residents of Shika town, Japan, between 2011 and 2017. A total of 402 non-diabetic men, including participants with normal fasting plasma glucose (FPG) and impaired FPG (FPG 5.6-6.9 mmol/L), and aged ≥40 years, were examined. FPG, the homeostasis model assessment of insulin secretion capacity (HOMA-B) and alcohol consumption were evaluated and compared between the body mass index (BMI) <25 and BMI ≥25 groups.

RESULTS

HOMA-B levels were lower in the BMI <25 group than in the BMI ≥25 group. Alcohol consumption correlated with a low HOMA-B level regardless of BMI, and, thus, the HOMA-B levels of alcohol drinkers were significantly lower in the BMI <25 group. A multivariable logistic regression analysis showed that alcohol consumption, even light-to-moderate consumption (1-25 g/day), was associated with significantly low levels of HOMA-B and impaired FPG in the BMI <25 group. Among participants with impaired FPG, a low level of HOMA-B was observed in alcohol drinkers, but not in non-drinkers. In contrast, light-to-moderate alcohol consumption was not related to HOMA-B or FPG in the BMI ≥25-group.

CONCLUSION

Alcohol consumption, even a small amount, might contribute to reductions in HOMA-B levels and impaired FPG in lean/normal-weight Japanese men.

Genetic ablation of C-reactive protein gene confers resistance to obesity and insulin resistance in rats

AIMS/HYPOTHESIS

Besides serving as a traditional inflammatory marker, C-reactive protein (CRP) is closely associated with the development of obesity, diabetes and cardiovascular diseases as a metabolic and inflammatory marker. We hypothesise that CRP protein directly participates in the regulation of energy and glucose metabolism rather than just being a surrogate marker, and that genetic deficiency of CRP will lead to resistance to obesity and insulin resistance.

METHODS

Crp gene deletion was achieved by transcription activator-like effector nuclease (TALEN) technology in rats. The Crp knockout animals were placed on either a standard chow diet or a high-fat diet. Phenotypic changes in body weight, glucose metabolism, insulin sensitivity, energy expenditure and inflammation condition were examined. The central impact of CRP deficiency on leptin and insulin hypothalamic signalling, as well as glucose homeostasis, were examined via intracerebral ventricular delivery of leptin and CRP plus glucose clamp studies in the wild-type and Crp knockout rats.

RESULTS

CRP deficiency led to a significant reduction in weight gain and food intake, elevated energy expenditure and improved insulin sensitivity after exposure to high-fat diet. Glucose clamp studies revealed enhanced hepatic insulin signalling and actions. Deficiency of CRP enhanced and prolonged the weight-reducing effect of central injected leptin and promoted the central and peripheral roles of leptin. By contrast, reinstatement of CRP into the hypothalamus of the knockout rats attenuated the effects of central leptin signalling on insulin sensitivity and peripheral glucose metabolism.

CONCLUSIONS/INTERPRETATION

This study represents the first line of genetic evidence that CRP is not merely a surrogate blood marker for inflammation and metabolic syndromes but directly regulates energy balance, body weight, insulin sensitivity and glucose homeostasis through direct regulation of leptin's central effect and hypothalamic signalling.

Modest alcohol consumption and risk of advanced liver fibrosis in nonalcoholic fatty liver disease: a systematic review and meta-analysis

Background

Recent studies have suggested an association between modest alcohol consumption and a decreased risk of advanced liver fibrosis among patients with nonalcoholic fatty liver disease (NAFLD) although the results are inconsistent. The current systematic review and meta-analysis was conducted to comprehensively investigate this possible association by identifying all the relevant studies and combining their results.

Methods

A comprehensive literature review was conducted utilizing the MEDLINE and EMBASE databases through February 2019 to identify all cross-sectional studies that compared the prevalence of advanced liver fibrosis among NAFLD patients who were modest alcohol drinkers to NAFLD patients who were non-drinkers. Effect estimates from each study were extracted and combined together using the random-effect, generic inverse variance method of DerSimonian and Laird.

Results

A total of 6 studies with 8,936 participants fulfilled the eligibility criteria and were included in the meta-analysis. The risk of advanced liver fibrosis among patients with NAFLD who were modest alcohol drinkers was significantly lower compared to patients with NAFLD who were non-drinkers with a pooled odds ratio of 0.51 (95% confidence interval [CI] 0.35-0.75; I² 47%). The funnel plot was symmetric and was not suggestive of publication bias.

Conclusion

A significantly lower risk of advanced liver fibrosis was observed among NAFLD patients who were modest alcohol drinkers compared to non-drinkers in this meta-analysis.

Low-dose alcohol ameliorated high fat diet-induced anxiety-related behavior via enhancing adiponectin expression and activating the Nrf2 pathway

Long-term high-fat-diet (HFD)-induced obesity is associated with many comorbidities, such as cognitive impairment and anxiety, which are increasing public health burdens that have gained prevalence in adolescents. Although low-dose alcohol could attenuate the risk of cardiovascular disease, its mechanism on HFD-induced anxiety-related behavior remains not clear. The mice were divided into 4 groups, Control (Con), Alcohol (Alc), HFD and HFD + Alc groups. To verify the effects of low-dose alcohol on HFD-induced anxiety-related behavior, the mice were fed with HFD for 16 weeks. At the beginning of week 13, the HFD-fed mice were administered intragastrically with low-dose alcohol (0.8 g kg^-1) for 4 weeks. After 4 weeks of oral administration, low-dose alcohol decreased body weight and Lee's index in HFD-induced obese mice. Moreover, low-dose alcohol alleviated the anxiety-related behaviors of obese mice in the open field test and the elevated plus maze test. The HFD-induced damage to the hippocampus was improved in hematoxylin-eosin staining assay in mice. In addition, low-dose alcohol also suppressed HFD-induced oxidative stress and increased HFD-suppressed adiponectin (APN) expression and nuclear factor erythroid 2-related factor 2 (Nrf2) activation in the hippocampus. Taken together, low-dose alcohol significantly ameliorates HFD-induced obesity, oxidative stress and anxiety-related behavior in mice, which might be related to APN upregulation, Nrf2 activation and related antioxidase expression including SOD1, HO-1, and catalase.

Tumour Necrosis Factor in Neuroplasticity, Neurogenesis and Alcohol Use Disorder

Alcohol use disorder is a pervasive and detrimental condition that involves changes in neuroplasticity and neurogenesis. Alcohol activates the neuroimmune system and alters the inflammatory status of the brain. Tumour necrosis factor (TNF) is a well characterised neuroimmune signal but its involvement in alcohol use disorder is unknown. In this review, we discuss the variable findings of TNF's effect on neuroplasticity and neurogenesis. Acute ethanol exposure reduces TNF release while chronic alcohol intake generally increases TNF levels. Evidence suggests TNF potentiates excitatory transmission, promotes anxiety during alcohol withdrawal and is involved in drug use in rodents. An association between craving for alcohol and TNF is apparent during withdrawal in humans. While anti-inflammatory therapies show efficacy in reversing neurogenic deficit after alcohol exposure, there is no evidence for TNF's essential involvement in alcohol's effect on neurogenesis. Overall, defining TNF's role in alcohol use disorder is complicated by poor understanding of its variable effects on synaptic transmission and neurogenesis. While TNF may be of relevance during withdrawal, the neuroimmune system likely acts through a larger group of inflammatory cytokines to alter neuroplasticity and neurogenesis. Understanding the individual relevance of TNF in alcohol use disorder awaits a more comprehensive understanding of TNF's effects within the brain.

Alcohol-induced impaired insulin secretion in a Japanese population: 5-year follow up in the Gifu Diabetes Study

AIMS/INTRODUCTION

Although moderate alcohol consumption lowers the risk of type 2 diabetes in European populations, the same cannot be assumed for Japanese patients with diabetes related to low insulin secretion rather than resistance. We aimed to evaluate the effects of daily alcohol consumption on glucose tolerance and diabetes development risk in Japanese populations.

MATERIALS AND METHODS

This retrospective study randomly enrolled 452 men and 659 women aged 40-78 years in 2005 (Gifu, Japan). The participants completed a 75-g oral glucose tolerance test and medical questionnaire. The homeostasis model assessment of insulin resistance, homeostasis model assessment of β-cell function and insulinogenic index were used to estimate insulin sensitivity and secretion. The relationships between alcohol consumption and these parameters were analyzed using logistic regression after adjusting for potential confounders. The 5-year changes in hemoglobin A1c levels were also evaluated.

RESULTS

The adjusted odds ratios for elevated homeostasis model assessment of β-cell function values (<40%) in the 0-19.9 g/day, 20.0-39.9 g/day and ≥ 40 g/day alcohol consumption groups were 0.98, 1.46 and 2.68, respectively. Alcohol consumption induced a significant decrease in the insulin secretion level among the ≥40 g/day drinkers, especially in men. However, there was no risk of increased insulin resistance based on the homeostasis model assessment of insulin resistance (<2.5) results. The 5-year risk of elevated hemoglobin A1c levels (≥6.5%) was increased according to increase in alcohol consumption in both men and women.

CONCLUSIONS

Daily alcohol consumption was associated with reduced insulin secretion and an increased diabetes development risk in Japanese populations.

Drinking Frequency but not Years may be Associated with Lower Urinary Tract Symptoms: Result from a Large Cross-Sectional Survey in Chinese Men

Objective

To evaluate the effect of the drinking frequency and years on lower urinary tract symptoms (LUTS) in a large Chinese male population.

Methods

The current data were obtained from a consecutive series of 3,229 men aged 18–79 who participated in a routine physical examination in Fangchenggang First People’s Hospital, Guangxi, China. During a face-to-face interview, the detailed demographic variables about alcohol consumption, potential confounding factors were collected. LUTS were assessed by International Prostate Symptom Score (IPSS) and defined as total LUTS, irritative (IRR) and obstructive (OBS) symptoms, respectively. Multivariate logistic regression analysis was used to evaluate the risk of total LUTS, IRR and OBS symptoms affected by alcohol consumption.

Results

The prevalence of moderate to severe LUTS was 8.3% and apparently increased with age (P<0.001). A significant distribution presented in age, alcohol consumption, BMI, cigarette smoking, education attainment and hypertension among different strata of LUTS severity (P<0.05). Men who drank 1–2 times per week were less likely to have OBS symptoms (OR=0.45, 95%CI=0.29–0.70) regardless of age (OR=0.52, 95%CI=0.33–0.82) or multivariate adjusted (OR=0.52, 95%CI=0.33–0.83). Nevertheless, we did not observe a significant negative or positive association presented between drinking years and the risk of total LUTS, OBS and IRR symptoms.

Conclusion

The current results imply that moderate drinking frequency may be protective against LUTS, and drinking years did not relate to worsening or improving LUTS.

Pro-inflammatory signalling and gut-liver axis in non-alcoholic and alcoholic steatohepatitis: Differences and similarities along the path

Non-alcoholic fatty liver disease (NAFLD) and alcohol-associated liver disease (ALD) represent a spectrum of injury, ranging from simple steatosis to steatohepatitis and cirrhosis. In humans, in fact, fatty changes in the liver, possibly leading to end-stage disease, were observed after chronic alcohol intake or in conditions of metabolic impairment. In this article, we examined the features and the pro-inflammatory pathways leading to non-alcoholic and alcoholic steatohepatitis. The involvement of several events (hits) and multiple inter-related pathways in the pathogenesis of these diseases suggest that a single therapeutic agent is unlikely to be an effective treatment strategy. Hence, a combination treatment towards multiple pro-inflammatory targets would eventually be required. Gut-liver crosstalk is involved not only in the impairment of lipid and glucose homoeostasis leading to steatogenesis, but also in the initiation of inflammation and fibrogenesis in both NAFLD and ALD. Modulation of the gut-liver axis has been suggested as a possible therapeutic approach since gut-derived components are likely to be involved in both the onset and the progression of liver damage. This review summarizes the translational mechanisms underlying pro-inflammatory signalling and gut-liver axis in non-alcoholic and alcoholic steatohepatitis. With a multitude of people being affected by liver diseases, identification of possible treatments and the elucidation of pathogenic mechanisms are elements of paramount importance.

Dietary Habits and Nutrition in Rheumatoid Arthritis: Can Diet Influence Disease Development and Clinical Manifestations?

Rheumatoid arthritis (RA) is a systemic, autoimmune disease characterized by joint involvement, with progressive cartilage and bone destruction. Genetic and environmental factors determine RA susceptibility. In recent years, an increasing number of studies suggested that diet has a central role in disease risk and progression. Several nutrients, such as polyunsaturated fatty acids, present anti-inflammatory and antioxidant properties, featuring a protective role for RA development, while others such as red meat and salt have a harmful effect. Gut microbiota alteration and body composition modifications are indirect mechanisms of how diet influences RA onset and progression. Possible protective effects of some dietary patterns and supplements, such as the Mediterranean Diet (MD), vitamin D and probiotics, could be a possible future adjunctive therapy to standard RA treatment. Therefore, a healthy lifestyle and nutrition have to be encouraged in patients with RA.

Prospective Associations of Serum Adiponectin, Leptin, and Leptin-Adiponectin Ratio with Incidence of Metabolic Syndrome: The Korean Genome and Epidemiology Study

Although the role of adiponectin and leptin in the etiology of metabolic syndrome (MetS) has been explored in various populations, limited knowledge is available on the prospective association of adiponectin and leptin with the risk of MetS development. The present study aimed to evaluate the associations of adiponectin, leptin, and the leptin-adiponectin (LA) ratio with the future risk of MetS in middle-aged and older Korean adults. Using a prospective, population-based Ansan-Ansung cohort of the Korean Genome and Epidemiology Study (KoGES), 2691 Korean adults (1317 men and 1374 women) were included in the present study. Serum adiponectin and leptin concentrations were measured using commonly available enzyme-linked immunosorbent assay kits. Multivariable Cox proportional hazard models were used to investigate the relationships of the different adiponectin and leptin concentrations and LA ratio with the incident MetS. During a mean follow-up of 6.75 years, a total of 359 (27.26%) men and 385 (28.02%) women were identified as developing new-onset MetS. After controlling for covariates, higher adiponectin levels were associated with lower incidence of MetS (hazard ratio (HR) for third vs. first tertile: 0.53, 95% confidence interval (CI): 0.40–0.70 for men and HR: 0.54, 95% CI: 0.42–0.71 for women), while higher leptin levels (HR for third vs. first tertile: 2.88, 95% CI: 2.01–4.13 for men and HR: 1.55, 95% CI: 1.13–2.13 for women) and LA ratio (HR for third vs. first tertile: 3.07, 95% CI: 2.13–4.44 for men and HR: 1.94, 95% CI: 1.41–2.66 for women) were associated with an increased incidence of MetS. Among men, in the fully adjusted models an increase by one standard deviation (SD) in adiponectin levels was associated with a 10% decrease in MetS risk (HR per SD: 0.90, 95% CI: 0.85–0.95) while leptin and LA ratio was associated with a 5% (HR per SD: 1.05, 95% CI: 1.01–1.08) and 40% (HR per SD: 1.40, 95% CI: 1.22–1.62) increase in MetS risk, respectively. Among women, a significant association with MetS risk was observed only in adiponectin levels (HR per SD: 0.91, 95% CI: 0.88–0.95). We found that higher adiponectin level was associated with a lower risk of MetS, while higher leptin level and LA ratio were associated with elevated MetS incidence, irrespective of body mass index at baseline in both Korean men and women. Adiponectin and leptin levels and LA ratio could play a role as a useful biomarker in the prediction of future MetS development among middle-aged and older Koreans.

Alcohol and Human Health: What Is the Evidence?

Alcohol consumption has long been a part of human culture. However, alcohol consumption levels and alcohol consumption patterns are associated with chronic diseases. Overall, light and moderate alcohol consumption (up to 14 g per day for women and up to 28 g per day for men) may be associated with reduced mortality risk, mainly due to reduced risks for cardiovascular disease and type-2 diabetes. However, chronic heavy alcohol consumption and alcohol abuse lead to alcohol-use disorder, which results in physical and mental diseases such as liver disease, pancreatitis, dementia, and various types of cancer. Risk factors for alcohol-use disorder are largely unknown. Alcohol-use disorder and frequent heavy drinking have detrimental effects on personal health.

Risks of Light and Moderate Alcohol Use in Fatty Liver Disease: Follow-Up of Population Cohorts

BACKGROUND AND AIMS

The effects of alcohol use in nonalcoholic fatty liver disease are unclear. We investigated the impact of alcohol use in fatty liver disease on incident liver, cardiovascular, and malignant disease, as well as death.

APPROACH AND RESULTS

Our study comprised 8,345 persons with hepatic steatosis (fatty liver index >60) who participated in health-examination surveys (FINRISK 1992-2012 or Health 2000), with available data on baseline alcohol intake. Main exclusions were baseline clinical liver disease, viral hepatitis, ethanol intake >50 g/day, and current abstainers. Data were linked with national registers for hospital admissions, malignancies, and death regarding liver, cardiovascular, and malignant disease, as well as all-cause death. Adjustment were for multiple confounders. Alcohol consumption showed a dose-dependent risk increase for incident advanced liver disease and malignancies. Consuming 10-19 g/day of alcohol in general or 0-9 g/day as nonwine beverages doubled the risk for advanced liver disease compared to lifetime abstainers. In contrast, alcohol intake up to 49 g/day was associated with a 22%-40% reduction of incident cardiovascular disease (CVD). We observed a J-shaped association between alcohol intake and all-cause death with a maximal risk reduction of 21% (95% confidence interval, 5%-34%) at alcohol intake of 0-9 g/day compared to lifetime abstainers. However, these benefits on CVD and mortality were only observed in never smokers. Alcohol intake >30 g/day yielded increased risk estimates for mortality compared to lifetime abstainers. In a subpopulation with longitudinal data, alcohol intake remained stable over time in >80% of subjects.

CONCLUSIONS

Even low alcohol intake in fatty liver disease is associated with increased risks for advanced liver disease and cancer. Low to moderate alcohol use is associated with reduced mortality and CVD risk but only among never smokers.

Ethnopharmacological Applications Targeting Alcohol Abuse: Overview and Outlook

Excessive alcohol consumption is the cause of several diseases and thus is of a major concern for society. Worldwide alcohol consumption has increased by many folds over the past decades. This urgently calls for intervention and relapse counteract measures. Modern pharmacological solutions induce complete alcohol self-restraint and prevent relapse, but they have many side effects. Natural products are most promising as they cause fewer adverse effects. Here we discuss in detail the medicinal plants used in various traditional/folklore medicine systems for targeting alcohol abuse. We also comprehensively describe preclinical and clinical studies done on some of these plants along with the possible mechanisms of action.

Role of Mechanistic Target of Rapamycin and Autophagy in Alcohol-Induced Adipose Atrophy and Liver Injury

Chronic alcohol consumption induces adipose tissue atrophy. However, the mechanisms for how alcohol induces lipodystrophy and its impact on liver steatosis and injury are not fully elucidated. Autophagy is a highly conserved lysosomal degradation pathway, which regulates cellular homeostasis. Mice with autophagy deficiency in adipose tissue have impaired adipogenesis. However, whether autophagy plays a role in alcohol-induced adipose atrophy and how altered adipocyte autophagy contributes to alcohol-induced liver injury remain unclear. To determine the role of adipose autophagy and mechanistic target of rapamycin (mTOR) in alcohol-induced adipose and liver pathogenesis, we generated adipocyte-specific Atg5 knockout (KO), adipocyte-specific mTOR KO, adipocyte-specific Raptor KO, and adipocyte-specific tuberous sclerosis complex 1 KO mice by crossing floxed mice with Adipoq-Cre. The KO mice and their matched wild-type mice were challenged with chronic-plus-binge alcohol mouse model. Chronic-plus-binge alcohol induced adipose atrophy with increased autophagy and decreased Akt/mTOR signaling in epididymal adipose tissue in wild-type mice. Adipocyte-specific Raptor KO mice experienced exacerbated alcohol-induced steatosis, but neither adipocyte-specific mTOR nor adipocyte-specific tuberous sclerosis complex 1 KO mice exhibited similar detrimental effects. Adipocyte-specific Atg5 KO mice had increased circulating levels of fibroblast growth factor 21 and adiponectin and were resistant to alcohol-induced adipose atrophy and liver injury. In conclusion, autophagy deficiency in adipose tissue leads to reduced sensitivity to alcohol-induced adipose atrophy, which ameliorates alcohol-induced liver injury in mice.

Impact of Red Wine Consumption on Cardiovascular Health

BACKGROUND

The devastating effects of heavy alcohol drinking have been long time recognized. In the last decades, potential benefits of modest red wine drinking were suggested. In European countries in which red wide intake is not negligible (such as France), the association between cholesterol and cardiovascular (CV) risk was less evident, suggesting the action of some protective molecules in red wine or other foods and drinks.

METHODS

This narrative review is based on the material searched for and obtained via PubMed up to May 2016. The search terms we used were: "red wine, cardiovascular, alcohol" in combination with "polyphenols, heart failure, infarction".

RESULTS

Epidemiological and mechanistic evidence of a J-shaped relationship between red wine intake and CV risk further supported the "French paradox". Specific components of red wine both in vitro and in animal models were discovered. Polyphenols and especially resveratrol largely contribute to CV prevention mainly through antioxidant properties. They exert beneficial effects on endothelial dysfunction and hypertension, dyslipidemia, metabolic diseases, thus reducing the risk of adverse CV events such as myocardial infarction ischemic stroke and heart failure. Of interest, recent studies pointed out the role of ethanol itself as a potential cardioprotective agent, but a clear epidemiological evidence is still missing. The aim of this narrative review is to update current knowledge on the intracellular mechanism underlying the cardioprotective effects of polyphenols and ethanol. Furthermore, we summarized the results of epidemiological studies, emphasizing their methodological criticisms and the need for randomized clinical trials able to clarify the potential role of red wine consumption in reducing CV risk.

CONCLUSION

Caution in avowing underestimation of the global burden of alcohol-related diseases was particularly used.

Compared to non-drinkers, individuals who drink alcohol have a more favorable multisystem physiologic risk score as measured by allostatic load

Aims

Alcohol use is associated with both positive and negative effects on individual cardiovascular risk factors, depending upon which risk factor is assessed. The present analysis uses a summative multisystem index of biologic risk, known as allostatic load (AL), to evaluate whether the overall balance of alcohol-associated positive and negative cardiovascular risk factors may be favorable or unfavorable.

Methods

This analysis included 1255 adults from the Midlife in the United States (MIDUS) biomarker substudy. Participants, average age 54.5 (±11) years, were divided into 6 alcohol-use categories based on self-reported drinking habits. Current non-drinkers were classified as lifelong abstainers and former light drinkers, former moderate drinkers, or former heavy drinkers. Current alcohol users were classified as light, moderate, or heavy drinkers. A total AL score was calculated using 24 biomarkers grouped into 7 physiologic systems including cardiovascular, inflammation, glucose metabolism, lipid metabolism, sympathetic and parasympathetic nervous systems, and the hypothalamic-pituitary-adrenal axis. Mixed-effects regression models were fit to determine the relationship between alcohol use categories and AL with controls for covariates that may influence the relationship between alcohol use and AL.

Results

468 (37.6%) individuals were current non-drinkers while 776 (62.4%) were current drinkers. In adjusted mixed-effects regression models, all 3 groups of current drinkers had significantly lower average AL scores than the lifelong abstainer/former light drinker group (light: -0.23, 95% CI -0.40, -0.07, p < 0.01; moderate: -0.20, 95% CI -0.38, -0.02, p < 0.05; heavy: -0.30, 95% CI -0.57, -0.04, p < 0.05), while the average AL scores of former moderate and former heavy drinkers did not differ from the lifelong abstainer/former light drinker group.

Conclusions

Current alcohol use is associated cross-sectionally with a favorable multisystem physiologic score known to be associated with better long-term health outcomes, providing evidence in support of long-term health benefits related to alcohol consumption.

Comparison of the effect of light alcohol consumption on Japanese men with and without fatty liver

Light and moderate drinking is associated with lower risk of metabolic syndrome (Mets)-related diseases in the general population. Non-alcoholic fatty liver disease (NAFLD) is considered to be a phenotype of Mets in the liver. Although there have been some reports of the association between NAFLD and light alcohol consumption (LAC), the association between Mets-related diseases and LAC in the subjects with and without fatty liver is unclear. Therefore, this study aimed to determine the influence of LAC on Mets-related diseases in individuals with and those without fatty liver. This study included 1,190 men who underwent regular health check-ups and consumed <20 g/day of alcohol. The subjects were divided into two groups, the non-fatty liver group and fatty liver group, and investigated the association between Mets-related diseases and LAC. Fatty liver was diagnosed by abdominal ultrasound. The effect of LAC was different between the non-fatty liver and fatty liver groups. In the non-fatty liver group, the odds ratio (OR) for hypertension was 1.73 (1.04-2.88;2 P=0.035). In the fatty liver group, the OR for each Mets-related diseases were as follows: Dyslipidemia, 0.64 (0.44-0.95, P=0.028); impaired glucose tolerance 0.57 (0.37-0.88; P=0.012); chronic kidney disease, 0.58 (0.36-0.94; P=0.029); and Mets by Japanese criteria, 0.63 (0.44-0.92; P=0.016). The influence of LAC on Mets-related diseases differs based on the presence of fatty liver. In individuals without fatty liver, light drinking is an independent risk factor for hypertension.

Effect of Alcohol Consumption on Survival in Nonalcoholic Fatty Liver Disease: A National Prospective Cohort Study

Nonalcoholic fatty liver disease (NAFLD) comprises more than two thirds of patients with chronic liver disease in the United States. The effect of alcohol consumption on survival in patients with NAFLD is not clear. We gathered data on National Health and Nutrition Examination Survey participants from 1988 to 2010, and linked them to the National Death Index for follow-up of their survival. We diagnosed NAFLD based on a previously validated biochemical model (Hepatic Steatosis Index). We built multivariate Cox proportional hazards models to evaluate the effect of alcohol consumption on survival of patients with NAFLD. After excluding participants with significant alcohol use, viral hepatitis, or increased transferrin saturation, 4,568 participants with NAFLD were included in the analysis. In a Cox model adjusted for age, sex, and smoking history, drinking 0.5-1.5 drinks per day decreased the risk of overall mortality by 41% (hazard ratio [HR] = 0.59, 95% confidence interval [CI] 0.40-0.85, P = 0.005) compared with not drinking. Drinking ≥1.5 drinks per day showed a trend toward harm (HR = 1.16, 95% CI 0.99-1.36, P = 0.119). After further adjustment for race, physical activity, education level, diabetes, and fiber and polyunsaturated fatty acid intake, drinking 0.5-1.5 drinks per day continued to show a significant protective effect (HR = 0.64, 95% CI 0.42-0.97, P = 0.035), and drinking ≥1.5 drinks per day showed a significant harmful effect on mortality (HR = 1.45, 95% CI 1.01-2.10, P = 0.047). Among patients with NAFLD, modest alcohol consumption is associated with a significant decrease in all-cause mortality, whereas drinking ≥1.5 drinks per day is associated with an increase in mortality. These results help to inform the discussion of potential risks and benefits of alcohol use in patients with NAFLD.

Obesity in acute alcoholic hepatitis increases morbidity and mortality

BACKGROUND

Alcohol and obesity synergise to increase the risk of liver-related mortality. We examined the influence of adiposity on clinical outcomes in alcoholic hepatitis (AH) and the underlying inflammatory crosstalk between adipose tissue (AT) and the liver.

METHODS

A cohort of 233 patients with AH from the UK and USA provided data to analyse the effects of obesity in AH. Body mass index was corrected for the severity of ascites, termed cBMI. Inflammatory and metabolic profiling was undertaken by proteome analysis of human serum samples. The effect of alcohol on adipose tissue and CXCL11 expression was studied in 3 T3-derived adipocytes and in mice using the high-fat diet-plus-binge ethanol model.

FINDINGS

Obesity was common amongst patients with AH, seen in 19% of individuals. Obesity (HR 2.22, 95%CI 1.1-4.3, p = .022) and underweight (HR 2.38, 1.00-5.6, p = .049) were independently associated with mortality at 3 months. Proteome analysis demonstrated multiple metabolic and inflammatory factors differentially expressed in obese AH verse lean AH, with CXCL11 being the most elevated factor in obese AH. In vitro analysis of cultured adipocytes and in vivo analysis of mouse models showed that alcohol induced CXCL11 expression in AT, but not in liver.

INTERPRETATION

Obesity is common in AH and associated with a greater than two-fold increase in short-term mortality. Obese AH is associated with a different inflammatory phenotype, with the greatest elevation in CXCL11. These data confirm that adiposity is clinically important in acute alcohol-related liver disease and illustrate the adipose-liver inflammatory axis in AH. FUND: This work was supported in part by an EASL Sheila Sherlock Physician Scientist Fellowship. The funder played no role in gathering or analysing data or writing the manuscript. This paper presents independent research supported by the NIHR Birmingham Biomedical Research Centre at the University Hospitals Birmingham NHS Foundation Trust and the University of Birmingham. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

Effects of Moderate Ethanol Consumption on Lipid Metabolism and Inflammation Through Regulation of Gene Expression in Rats

Aims

Epidemiological studies and experimental data from rodent models have reported a non-linear relationship between consumption of alcohol and cardiovascular disease (CVD) risk that suggests that light-to-moderate drinking as opposed to excessive consumption may provide some cardiovascular benefits. The present study examined potential mechanisms by which moderate alcohol consumption may provide a protective effect against CVD.

Short summary

Wistar rats exposed for 3 months to a 20% ethanol intermittent-access voluntary drinking paradigm displayed a reduction in epididymal fat, blood glucose and non-HDL and total cholesterol. These effects were accompanied by decreased expression of Hmgcr, Srebp-2, Cox-2 and RelA, indicating downregulation of genes involved in cholesterol synthesis and inflammation.

Methods

Twenty-four male Wistar rats voluntarily consumed a 20% v/v ethanol solution on alternate days for 13 weeks (ethanol-treated) or were given access to water alone (non-ethanol-exposed control).

Results

There was no difference in body weight gain between the two groups, however, epididymal fat weight was lower in ethanol-fed rats (P = 0.030). Blood glucose, total cholesterol, non-high-density lipoprotein (HDL) and oxidized low-density lipoprotein (LDL) levels were lower in the ethanol group compared to controls (P < 0.05). There was a significant reduction in the expression of hydroxymethylglutaryl-coenzyme A reductase and sterol regulatory element-binding protein-2 in ethanol-treated rats (P < 0.05), suggesting that ethanol may have lowered cholesterol levels via downregulation of genes involved in cholesterol synthesis. Paraoxonase-1, which is associated with inhibition of LDL cholesterol oxidation, was upregulated in the ethanol group (P = 0.029). Ethanol-treated rats exhibited significantly lower levels of high-mobility box group protein 1 (P ≤ 0.05). Cyclooxygenase-2 and RelA gene expression were significantly lower in ethanol-treated rats (P < 0.05), indicating possible anti-inflammatory effects.

Conclusions

These findings suggest that moderate ethanol consumption may potentially contribute to improved cardiovascular outcomes by reducing body fat, improving blood cholesterol and blood glucose, and modulation of gene expression involved in inflammation and/or cholesterol synthesis.

Early vascular damage from smoking and alcohol in teenage years: the ALSPAC study

Aims

To determine the impact of smoking and alcohol exposure during adolescence on arterial stiffness at 17 years.

Methods and results

Smoking and alcohol use were assessed by questionnaires at 13, 15, and 17 years in 1266 participants (425 males and 841 females) from the ALSPAC study. Smoking status (smokers and non-smoker) and intensity ('high' ≥100, 'moderate' 20-99, and 'low or never' <20 cigarettes in lifetime) were ascertained. Participants were classified by frequency (low or high) and intensity of drinking [light (LI <2), medium (MI 3-9), and heavy (HI >10 drinks on a typical drinking day)]. Carotid to femoral pulse wave velocity (PWV) was assessed at 17 years [mean ± standard deviation and/or mean difference (95% confidence intervals)]. Current smokers had higher PWV compared with non-smokers (P = 0.003). Higher smoking exposure was associated with higher PWV compared with non-smokers [5.81 ± 0.725 vs. 5.71 ± 0.677 m/s, mean adjusted difference 0.211 (0.087-0.334) m/s, P = 0.001]. Participants who stopped smoking had similar PWV to never smokers (P = 0.160). High-intensity drinkers had increased PWV [HI 5.85 ± 0.8 vs. LI 5.67 ± 0.604 m/s, mean adjusted difference 0.266 (0.055-0.476) m/s, P = 0.013]. There was an additive effect of smoking intensity and alcohol intensity, so that 'high' smokers who were also HI drinkers had higher PWV compared with never-smokers and LI drinkers [mean adjusted increase 0.603 (0.229-0.978) m/s, P = 0.002].

Conclusion

Smoking exposure even at low levels and intensity of alcohol use were associated individually and together with increased arterial stiffness. Public health strategies need to prevent adoption of these habits in adolescence to preserve or restore arterial health.

The sex specific effect of alcohol consumption on circulating levels of CTRP3

The goal of this project was to establish the effect of alcohol consumption on the circulating levels of the adipose tissue derived protein C1q TNF Related Protein 3 (CTRP3). Adipose tissue secretes several adipokines, such as adiponectin and leptin, which exert a multitude of biological effects important for human health. However, adipose tissue is extremely sensitive to alcohol consumption, leading not only to disrupted fat storage, but also to disruptions in adipokine production. Changes to adipokine secretion could have widespread biological effects and potentially contribute to alcohol-induced ailments, such as alcoholic fatty liver disease (ALD). CTRP3 has been previously demonstrated to attenuate fatty liver disease, and suppression of CTRP3 with alcohol consumption could contribute to development of and progression to alcoholic fatty liver disease. To examine the effect of ethanol consumption on circulating adipokine levels, male and female mice were fed an ethanol containing diet (Lieber-DeCarli 5% (v/v) ethanol diet) for 10-days followed by a single gavage of 5 g/kg ethanol (the NIAAA model), or for 6-weeks with no binge added (chronic model). In female mice, adiponectin levels increased ~2-fold in both models of ethanol feeding, but in male mice increased adiponectin levels were only observed after chronic ethanol feeding. On the other hand, in female mice, circulating CTRP3 levels decreased by ~75% and ~50% in the NIAAA and chronic model, respectively, with no changes observed in the male mice in either feeding model. Leptin levels were unchanged with ethanol feeding regardless of model or sex of mice. Lastly, chronic ethanol feeding led to a significant increase in mortality (~50%) in female mice, with no difference in relative ethanol consumption. These findings indicate that ethanol consumption can dysregulate adipokine secretion, but that the effects vary by sex of animal, method of ethanol consumption, and adipokine examined. These findings also indicate that female mice are more sensitive to the chronic effects of ethanol than male mice. Notably, this is the first study to document the effects of ethanol consumption on the circulating levels of CTRP3. Understanding the impact of excessive alcohol consumption on adipokine production and secretion could identify novel mechanisms of alcohol-induced human disease. However, the mechanism responsible for the increased sensitivity remains elusive.

Cigarette smoking is a risk factor for the onset of fatty liver disease in nondrinkers: A longitudinal cohort study

Background

The effect of cigarette smoking on the onset of nonalcoholic fatty liver disease (NAFLD) is unclear, especially that associated with drinking small amounts of alcohol. We conducted a longitudinal study to investigate the relationship between cigarette smoking and NAFLD onset, which was stratified according to the amount of alcohol consumed.

Methods

We enrolled 7,905 Japanese subjects who had received annual health checkups more than twice between April 2003 and August 2013, 4,045 of whom met at least one of the following exclusion criteria and were excluded: (a) fatty liver at baseline; (b) hepatitis B or hepatitis C; (c) alcohol consumption (men: ≥210 g/wk; women: ≥140 g/wk); (d) change in alcohol drinking status between baseline and the study’s endpoint; (e) change in cigarette smoking habits between baseline and the study’s endpoint; or (f) current treatment with antidiabetic agents, antihypertensive agents, and/or lipid-lowering agents. The remaining 3,860 subjects (1,512 men, 2,348 women) were divided into two groups based on average alcohol consumption.

Results

After adjusting for the variables associated with metabolic disease, smoking was associated with fatty liver disease onset compared with nonsmokers in nondrinkers (adjusted hazard ratio = 1.988, 95% confidence interval 1.057–3.595; p = 0.034). No association was found between smoking and fatty liver disease onset in the low alcohol consumption group (men: <210 g alcohol/week; women: <140 g alcohol/week). The fatty liver disease incidence increased significantly among the nondrinkers as the number of cigarettes smoked increased (p = 0.001).

Conclusions

Cigarette smoking may be a significant risk factor associated with NAFLD onset in nondrinkers. These results may help clinicians to identify patients who are at a high risk of developing NAFLD and to prevent the progression of NAFLD by promoting earlier interventions that help people discontinue unhealthy lifestyle habits.

Potential of resveratrol in mitigating metabolic disturbances induced by ethanol

Alcohol abuse is associated with numerous health problems, including metabolic disturbances and liver damage. Therefore, different compounds are continuously being tested to evaluate their potential effectiveness in reducing these harmful changes. Animal studies clearly show that resveratrol is capable of ameliorating some consequences of ethanol ingestion. Resveratrol is a naturally occurring diphenolic compound having pleiotropic, health-promoting properties. Its beneficial action have been also demonstrated in animal models with ethanol-induced metabolic disturbances and liver injury. In ethanol treated animals, resveratrol effectively reduced liver lipid accumulation. Moreover, this compound diminished necrosis of hepatocytes, and also reduced liver fibrosis. The hepatoprotective action of resveratrol is largely associated with its ant-oxidant and anti-inflammatory properties, and also covers changes in activities of some enzymes. It is known that this compound upregulates the adiponectin-SIRT1-AMPK signaling pathway in the liver. Resveratrol was also found to positively affect blood lipids in animals exposed to ethanol. Moreover, administration of resveratrol to animals with ethanol-induced hypoinsulinemia and insulin resistance was shown to alleviate these disturbances. These outcomes clearly indicate that resveratrol holds great potential to reduce some consequences of ethanol ingestion. However, human studies are required to fully assess its therapeutic value.

Effect of Alcohol Consumption on Cardiovascular Health

PURPOSE OF REVIEW

This review aims to discuss the effect of alcohol consumption on various cardiovascular (CV) diseases and CV mortality.

RECENT FINDINGS

Alcohol intake has consistently shown a J- or U-shaped relationship with several cardiovascular diseases. Light to moderate alcohol intake has been associated with lower risk of coronary artery disease, heart failure (HF), as well as CV mortality. On the other hand, heavy consumption has been associated with deleterious CV outcomes including increased mortality. However, the evidence is based from observational and population-based studies where risk of confounding cannot be excluded even after meticulous methodological approaches. This is compounded by conflicting data such as higher risk of certain CV diseases like HF in former drinkers compared to abstainers. Further, Mendelian randomization studies using genetic polymorphisms in enzymes have recently questioned the beneficial association of low-moderate drinking with CV system. There has been substantial and consistent evidence that light to moderate alcohol consumption have beneficial effect on overall cardiovascular profile and mortality. However, there are considerable limitations in the reported literature to determine a strong causality of a protective effect of moderate alcohol consumption by itself. Further robust studies or possibly a well-structured randomized controlled could bring an end to this debate.

Alcohol, adipose tissue and liver disease: mechanistic links and clinical considerations

Adipose tissue represents a large volume of biologically active tissue that exerts substantial systemic effects in health and disease. Alcohol consumption can profoundly disturb the normal functions of adipose tissue by inducing adipocyte death and altering secretion of adipokines, pro-inflammatory mediators and free fatty acids from adipose tissue, which have important direct and indirect effects on the pathogenesis of alcoholic liver disease (ALD). Cessation of alcohol intake quickly reverses inflammatory changes in adipose tissue, and pharmacological treatment that normalizes adipose tissue function improves experimental ALD. Obesity exacerbates liver injury induced by chronic or binge alcohol consumption, and obesity and alcohol can synergize to increase risk of ALD and progression. Physicians who care for individuals with ALD should be aware of the effects of adipose tissue dysfunction on liver function, and consider strategies to manage obesity and insulin resistance. This Review examines the effect of alcohol on adiposity and adipose tissue and the relationship between alcohol, adipose tissue and the liver.

Gender Differences in the Association between Moderate Alcohol Consumption and Hearing Threshold Shifts

Hearing loss is a global public health problem with a high prevalence, significantly impairing communication and leading to a decrease in the quality of life. The association between moderate alcohol consumption (MAC) and hearing impairment has been addressed in several studies with inconsistent results. The intent of our study is to clarify the correlation between MAC and the hearing threshold and further investigate the interplay between MAC and the hearing threshold categorized by gender. The study included 4,075 participants aged 20–69 years from the 1999–2004 data of National Health and Nutrition Examination Survey (NHANES). The associations among MAC, gender differences, and high-frequency and low-frequency hearing thresholds were analyzed. We found that current female drinkers with MAC tended to have lower hearing thresholds. There is a significant protective effect of MAC on hearing threshold shifts in the US adult population, especially in females. Our research was the first study to further indicate that there is a gender difference in the association between MAC and hearing impairment. In accordance with our results, if people drink, they should consume moderate rather than higher amounts, especially in women, which may result in a reduced risk of hearing loss.

Alcohol, Adipose Tissue and Lipid Dysregulation

Chronic alcohol consumption perturbs lipid metabolism as it increases adipose tissue lipolysis and leads to ectopic fat deposition within the liver and the development of alcoholic fatty liver disease. In addition to the recognition of the role of adipose tissue derived fatty acids in liver steatosis, alcohol also impacts other functions of adipose tissue and lipid metabolism. Lipid balance in response to long-term alcohol intake favors adipose tissue loss and fatty acid efflux as lipolysis is upregulated and lipogenesis is either slightly decreased or unchanged. Study of the lipolytic and lipogenic pathways has identified several regulatory proteins modulated by alcohol that contribute to these effects. Glucose tolerance of adipose tissue is also impaired by chronic alcohol due to decreased glucose transporter-4 availability at the membrane. As an endocrine organ, white adipose tissue (WAT) releases several adipokines that are negatively modulated following chronic alcohol consumption including adiponectin, leptin, and resistin. When these effects are combined with the enhanced expression of inflammatory mediators that are induced by chronic alcohol, a proinflammatory state develops within WAT, contributing to the observed lipodystrophy. Lastly, while chronic alcohol intake may enhance thermogenesis of brown adipose tissue (BAT), definitive mechanistic evidence is currently lacking. Overall, both WAT and BAT depots are impacted by chronic alcohol intake and the resulting lipodystrophy contributes to fat accumulation in peripheral organs, thereby enhancing the pathological state accompanying chronic alcohol use disorder.

Effects of alcohol abstinence on glucose metabolism in Japanese men with elevated fasting glucose: A pilot study

It has been demonstrated that moderate alcohol consumption provides protection against the development of type 2 diabetes. However, several other reports suggested that moderate alcohol intake may increase the risk of type 2 diabetes in non-obese Japanese. The aim of present study was to investigate the effect of 1-week alcohol abstinence on hepatic insulin sensitivity and fasting plasma glucose (FPG) in non-obese Japanese men. We recruited 8 non-obese Japanese men with mildly elevated FPG and drinking habits alcohol (mean frequency; 5.6 ± 2.5 times/week, mean alcohol consumption; 32.1 ± 20.0 g/day). Before and after the 1-week alcohol abstinence, we used the 2-step hyperinsulinemic-euglycemic clamp to measure endogenous glucose production (EGP) and insulin sensitivity (IS) in muscle and liver. One-week alcohol abstinence significantly reduced both FPG by 7% (from 105.5 ± 11.7 to 98.2 ± 7.8 mg/dl, P < 0.01) and fasting EGP by 6% (from 84.1 ± 4.2 to 77.6 ± 1.6 mg/m² per min, P < 0.01), respectively. Two–step clamp study showed that alcohol abstinence significantly improved hepatic-IS, but not muscle-IS. In conclusion, one week alcohol abstinence improved hepatic IS and FPG in non-obese Japanese men with mildly elevated FPG and drinking habits alcohol.

Is There a Role for Diet in the Therapy of Rheumatoid Arthritis?

Patients with rheumatoid arthritis (RA) often inquire about dietary interventions to improve RA symptoms. Although the majority of studies of diet and RA were published prior to the start of the twenty-first century, this review discusses the evidence for a relationship between diet, in particular omega-3 fatty acid supplements, vitamin D supplements, alcohol, and the Mediterranean diet and RA disease activity. We review possible mechanisms by which these dietary intakes may affect RA disease activity. Given the complexity of studying the relationship between diet and RA disease activity, we highlight areas deserving further study before specific recommendations can be made to RA patients.

Low alcohol consumption increases the risk of impaired glucose tolerance in patients with non-alcoholic fatty liver disease

BACKGROUND

Fatty liver disease is associated with glucose intolerance and hepatic insulin resistance. However, there are distinct etiologies for alcoholic versus non-alcoholic fatty liver disease (NAFLD), and it is unknown whether alcohol consumption influences the onset of glucose intolerance in fatty liver disease patients. Therefore, we investigated the relationship between fatty liver disease and the onset of impaired fasting glucose (IFG) with respect to alcohol consumption.

METHODS

The records of 6804 Japanese subjects were reviewed to identify those meeting the criteria for IFG. Male and female subjects were classified into five and four groups, respectively, based on average alcohol consumption (g/week). IFG onset was defined as fasting plasma glucose levels ≥110 mg/dl.

RESULTS

In the non-drinker, >0-70 g/week, >70-140 g/week, >140-210 g/week (men only), and >210 g/week (men only) or >140 g/week (women only) groups, 7.3, 6.7, 6.4, 9, and 6.4 % of men and 2, 1.7, 3.1, and 3.2 % of women, respectively, developed IFG. Fatty liver was positively associated with the onset of IFG in men of the >0-70 g/week group (adjusted hazard ratio [aHR], 2.808; 95 % confidence interval [CI] 1.605-5.049, p < 0.001) and women of the >70-140 g/week group (aHR, 4.193; 95 % CI, 1.036-14.584, p = 0.045) after adjusting for previously reported IFG risk factors. No associations were observed in the other groups.

CONCLUSIONS

A small amount of alcohol consumption is a significant risk factor for the onset of IFG in NAFLD patients; onset risk differs according to the amount of alcohol consumption.

The metabolic syndrome in patients with alcohol dependency: Current research and clinical implications

The relationship between alcohol dependency and disorders such as liver disease and cancer has been thoroughly researched. However, the effects of alcohol on cardiometabolic health remain controversial. Several reports found low to moderate alcohol consumption to be associated with a lower risk for cardiometabolic disorders. In contrast, excessive alcohol consumption has been related to an increased risk. Most of these studies were performed in non-clinical populations, therefore limiting the explanatory power to non-dependent patients. Only a few studies examined cardiovascular disorders and cardiovascular risk factors, in particular the metabolic syndrome (MetS), in alcohol dependent patients. We here present a narrative review of studies performed so far on the MetS in alcohol dependency, and provide current hypotheses on the association of alcohol dependency, appetite regulation and the development of the MetS.