Dose-dependent effects of chronic alcohol drinking on peripheral immune responses

Gut-liver axis: Recent concepts in pathophysiology in alcohol-associated liver disease

The growing recognition of the role of the gut microbiome's impact on alcohol-associated diseases, especially in alcohol-associated liver disease, emphasizes the need to understand molecular mechanisms involved in governing organ-organ communication to identify novel avenues to combat alcohol-associated diseases. The gut-liver axis refers to the bidirectional communication and interaction between the gut and the liver. Intestinal microbiota plays a pivotal role in maintaining homeostasis within the gut-liver axis, and this axis plays a significant role in alcohol-associated liver disease. The intricate communication between intestine and liver involves communication between multiple cellular components in each organ that enable them to carry out their physiological functions. In this review, we focus on novel approaches to understanding how chronic alcohol exposure impacts the microbiome and individual cells within the liver and intestine, as well as the impact of ethanol on the molecular machinery required for intraorgan and interorgan communication.

Effects of repeated alcohol abstinence on within-subject prefrontal cortical gene expression in rhesus macaques

Male rhesus monkeys (n = 24) had a biopsy of prefrontal cortical area 46 prior to chronic ethanol self-administration (n = 17) or caloric control (n = 7). Fourteen months of daily self-administration (water vs. 4% alcohol, 22 h access/day termed "open-access") was followed by two cycles of prolonged abstinence (5 weeks) each followed by 3 months of open-access alcohol and a final abstinence followed by necropsy. At necropsy, a biopsy of Area 46, contralateral to the original biopsy, was obtained. Gene expression data (RNA-Seq) were collected comparing biopsy/necropsy samples. Monkeys were categorized by drinking status during the final post-abstinent drinking phase as light (LD), binge (BD), heavy (HD) and very heavy (VHD drinkers). Comparing pre-ethanol to post-abstinent biopsies, four animals that converted from HD to VHD status had significant ontology enrichments in downregulated genes (necropsy minus biopsy n = 286) that included immune response (FDR < 9 × 10-7) and plasma membrane changes (FDR < 1 × 10-7). Genes in the immune response category included IL16 and 18, CCR1, B2M, TLR3, 6 and 7, SP2 and CX3CR1. Upregulated genes (N = 388) were particularly enriched in genes associated with the negative regulation of MAP kinase activity (FDR < 3 × 10-5), including DUSP 1, 4, 5, 6 and 18, SPRY 2, 3, and 4, SPRED2, BMP4 and RGS2. Overall, these data illustrate the power of the NHP model and the within-subject design of genomic changes due to alcohol and suggest new targets for treating severe escalated drinking following repeated alcohol abstinence attempts.

Associations of genetic variants within TYK2 with pulmonary tuberculosis among Chinese population

BACKGROUND

Pulmonary tuberculosis (PTB) is a common infectious disease caused by mycobacterium tuberculosis (MTB) and the present study aims to explore the associations of genetic variants within tyrosine kinases 2 (TYK2) with PTB incidence.

METHODS

A population-based case control study including 168 smear-positive PTB cases and 251 controls was conducted. Five single nucleotide polymorphisms (SNPs) including rs280520, rs91755, rs2304256, rs12720270, rs280519 located within TYK2 gene were selected and MassARRAY® MALDI-TOF system was employed for genotyping. SPSS 19.0 was adopted for statistical analysis, non-conditional logistic regression was conducted. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were computed to estimate their contributions to PTB incidence.

RESULTS

In the overall study population, rs91755 TT and rs280519 AA genotypes were found to be associated with reduced PTB risk (OR = 0.34, 95% CI: 0.16-0.72; OR = 0.38, 95% CI: 0.18-0.79, respectively). After stratification for sex, we found that among the male population, rs91755TG/TT, rs12720270AG/GG and rs280519AG/AA genotypes were associated with reduced PTB risk (OR = 0.41, 95% CI: 0.21-0.80; OR = 0.44, 95% CI: 0.21-0.94; OR = 0.42, 95% CI: 0.21-0.82, respectively). After stratification for age, we found that among those aged <60 years, rs91755TT and rs280519AA genotype were associated with reduced PTB risk (OR = 0.29, 95% CI: 0.09-0.90; OR = 0.34, 95% CI: 0.11-1.08, respectively); while rs2304256AC/AA genotype was associated with increased PTB risk (OR = 2.68, 95% CI: 1.05-6.85). Haplotype analysis revealed that AGAAG and ATCGA (Combined with rs280520, rs91755, rs2304256, rs12720270 and rs280519) were associated with increased (OR = 1.54, 95% CI: 1.01-2.37) and decreased PTB risk (OR = 0.70, 95% CI: 0.52-0.94), respectively.

CONCLUSIONS

The genetic variants located within TYK2 including rs91755, rs12720270 and rs280519 were found to be associated with modified PTB risk and the SNPs had potential to be the biomarkers to predict PTB incidence risk.

Alcohol use and the pain system

The World Health Organization's epidemiological data from 2016 revealed that while 57% of the global population aged 15 years or older had abstained from drinking alcohol in the previous year, more than half of the population in the Americas, Europe, and Western Pacific consumed alcohol. The spectrum of alcohol use behavior is broad: low-risk use (sensible and in moderation), at-risk use (e.g., binge drinking), harmful use (misuse) and dependence (alcoholism; addiction; alcohol use disorder). The at-risk use and misuse of alcohol is associated with the transition to dependence, as well as many damaging health outcomes and preventable causes of premature death. Recent conceptualizations of alcohol dependence posit that the subjective experience of pain may be a significant contributing factor in the transition across the spectrum of alcohol use behavior. This narrative review summarizes the effects of alcohol at all levels of the pain system. The pain system includes nociceptors as sensory indicators of potentially dangerous stimuli and tissue damage (nociception), spinal circuits mediating defensive reflexes, and most importantly, the supraspinal circuits mediating nocifensive behaviors and the perception of pain. Although the functional importance of pain is to protect from injury and further or future damage, chronic pain may emerge despite the recovery from, and absence of, biological damage (i.e., in the absence of nociception). Like other biological perceptual systems, pain is a construction contingent on sensory information and a history of individual experiences (i.e., learning and memory). Neuroadaptations and brain plasticity underlying learning and memory and other basic physiological functions can also result in pathological conditions such as chronic pain and addiction. Moreover, the negative affective/emotional aspect of pain perception provides embodied and motivational components that may play a substantial role in the transition from alcohol use to dependence.

Chronic alcohol consumption dysregulates innate immune response to SARS-CoV-2 in the lung

BACKGROUND

Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated.

METHODS

In this study we employed luminex, scRNA sequencing, and flow cytometry to investigate the impact of chronic alcohol consumption on SARS-CoV-2 anti-viral responses in bronchoalveolar lavage cell samples from humans with alcohol use disorder and rhesus macaques that engaged in chronic drinking.

FINDINGS

Our data show that in both humans (n = 6) and macaques (n = 11), the induction of key antiviral cytokines and growth factors was decreased with chronic ethanol consumption. Moreover, in macaques fewer differentially expressed genes mapped to Gene Ontology terms associated with antiviral immunity following 6 month of ethanol consumption while TLR signaling pathways were upregulated.

INTERPRETATION

These data are indicative of aberrant inflammation and reduced antiviral responses in the lung with chronic alcohol drinking.

FUNDING

This study was supported by NIH 1R01AA028735-04 (Messaoudi), U01AA013510-20 (Grant), R24AA019431-14 (Grant), R24AA019661 (Burnham), P-51OD011092 (ONPRC core grant support). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Integrated single cell analysis shows chronic alcohol drinking disrupts monocyte differentiation in the bone marrow

Chronic heavy alcohol drinking (CHD) rewires monocytes and macrophages toward heightened inflammatory states with compromised antimicrobial defenses that persist after 1-month abstinence. To determine whether these changes are mediated through alterations in the bone marrow niche, we profiled monocytes and hematopoietic stem cell progenitors (HSCPs) from CHD rhesus macaques using a combination of functional assays and single cell genomics. CHD resulted in transcriptional profiles consistent with increased activation and inflammation within bone marrow resident monocytes and macrophages. Furthermore, CHD resulted in transcriptional signatures associated with increased oxidative and cellular stress in HSCP. Differentiation of HSCP in vitro revealed skewing toward monocytes expressing "neutrophil-like" markers with greater inflammatory responses to bacterial agonists. Further analyses of HSCPs showed broad epigenetic changes that were in line with exacerbated inflammatory responses within monocytes and their progenitors. In summary, CHD alters HSCPs in the bone marrow leading to the production of monocytes poised to generate dysregulated hyper-inflammatory responses.

Patterns of IgA Autoantibody Generation, Inflammatory Responses and Extracellular Matrix Metabolism in Patients with Alcohol Use Disorder

Recent data have emphasized the role of inflammation and intestinal immunoglobulin A (IgA) responses in the pathogenesis of alcoholic liver disease (ALD). In order to further explore such associations, we compared IgA titers against antigens targeted to ethanol metabolites and tissue transglutaminase with pro- and anti-inflammatory mediators of inflammation, markers of liver status, transferrin protein desialylation and extracellular matrix metabolism in alcohol-dependent patients with or without liver disease and in healthy controls. Serum IgAs against protein adducts with acetaldehyde (HbAch-IgA), the first metabolite of ethanol, and tissue transglutaminase (tTG-IgA), desialylated transferrin (CDT), pro- and anti-inflammatory cytokines, markers of liver status (GT, ALP) and extracellular matrix metabolism (PIIINP, PINP, hyaluronic acid, ICTP and CTx) were measured in alcohol-dependent patients with (n = 83) or without (n = 105) liver disease and 88 healthy controls representing either moderate drinkers or abstainers. In ALD patients, both tTG-IgA and HbAch-IgA titers were significantly higher than those in the alcoholics without liver disease (p < 0.0005 for tTG-IgA, p = 0.006 for Hb-Ach-IgA) or in healthy controls (p < 0.0005 for both comparisons). The HbAch-IgA levels in the alcoholics without liver disease also exceeded those found in healthy controls (p = 0.0008). In ROC analyses, anti-tTG-antibodies showed an excellent discriminative value in differentiating between ALD patients and healthy controls (AUC = 0.95, p < 0.0005). Significant correlations emerged between tTG-IgAs and HbAch-IgAs (rs = 0.462, p < 0.0005), CDT (rs = 0.413, p < 0.0001), GT (rs = 0.487, p < 0.0001), alkaline phosphatase (rs = 0.466, p < 0.0001), serum markers of fibrogenesis: PIIINP (rs = 0.634, p < 0.0001), hyaluronic acid (rs = 0.575, p < 0.0001), ICTP (rs = 0.482, p < 0.0001), pro-inflammatory cytokines IL-6 (rs = 0.581, p < 0.0001), IL-8 (rs = 0.535, p < 0.0001) and TNF-α (rs = 0.591, p < 0.0001), whereas significant inverse correlations were observed with serum TGF-β (rs = -0.366, p < 0.0001) and CTx, a marker of collagen degradation (rs = -0.495, p < 0.0001). The data indicate that the induction of IgA immune responses toward ethanol metabolites and tissue transglutaminaseis a characteristic feature of patients with AUD and coincides with the activation of inflammation, extracellular matrix remodeling and the generation of aberrantly glycosylated proteins. These processes appear to work in concert in the sequence of events leading from heavy drinking to ALD.

Predictive risk markers in alcoholism

The medical disorders of alcoholism rank among the leading public health problems worldwide and the need for predictive and prognostic risk markers for assessing alcohol use disorders (AUD) has been widely acknowledged. Early-phase detection of problem drinking and associated tissue toxicity are important prerequisites for timely initiations of appropriate treatments and improving patient's committing to the objective of reducing drinking. Recent advances in clinical chemistry have provided novel approaches for a specific detection of heavy drinking through assays of unique ethanol metabolites, phosphatidylethanol (PEth) or ethyl glucuronide (EtG). Carbohydrate-deficient transferrin (CDT) measurements can be used to indicate severe alcohol problems. Hazardous drinking frequently manifests as heavy episodic drinking or in combinations with other unfavorable lifestyle factors, such as smoking, physical inactivity, poor diet or adiposity, which aggravate the metabolic consequences of alcohol intake in a supra-additive manner. Such interactions are also reflected in multiple disease outcomes and distinct abnormalities in biomarkers of liver function, inflammation and oxidative stress. Use of predictive biomarkers either alone or as part of specifically designed biological algorithms helps to predict both hepatic and extrahepatic morbidity in individuals with such risk factors. Novel approaches for assessing progression of fibrosis, a major determinant of prognosis in AUD, have also been made available. Predictive algorithms based on the combined use of biomarkers and clinical observations may prove to have a major impact on clinical decisions to detect AUD in early pre-symptomatic stages, stratify patients according to their substantially different disease risks and predict individual responses to treatment.

Chronic alcohol consumption dysregulates innate immune response to SARS-CoV-2 in the lung

Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated. Therefore, in this study we investigated the impact of chronic alcohol consumption on SARS-CoV-2 anti-viral responses in bronchoalveolar lavage cell samples from humans with alcohol use disorder and rhesus macaques that engaged in chronic drinking. Our data show that in both humans and macaques, the induction of key antiviral cytokines and growth factors was decreased with chronic ethanol consumption. Moreover, in macaques fewer differentially expressed genes mapped to Gene Ontology terms associated with antiviral immunity following 6 month of ethanol consumption while TLR signaling pathways were upregulated. These data are indicative of aberrant inflammation and reduced antiviral responses in the lung with chronic alcohol drinking.

Integrated single cell analysis shows chronic alcohol drinking disrupts monocyte differentiation in the bone marrow niche

Chronic alcohol drinking rewires circulating monocytes and tissue-resident macrophages towards heightened inflammatory states with compromised anti-microbial defenses. As these effects remain consistent in short-lived monocytes after a 1-month abstinence period it is unclear whether these changes are restricted to the periphery or mediated through alterations in the progenitor niche. To test this hypothesis, we profiled monocytes/macrophages and hematopoietic stem cell progenitors (HSCP) of the bone marrow compartment from rhesus macaques after 12 months of ethanol consumption using a combination of functional assays and single cell genomics. Bone marrow-resident monocytes/macrophages from ethanol-consuming animals exhibited heightened inflammation. Differentiation of HSCP in vitro revealed skewing towards monocytes expressing neutrophil-like markers with heightened inflammatory responses to bacterial agonists. Single cell transcriptional analysis of HSCPs showed reduced proliferation but increased inflammatory markers in mature myeloid progenitors. We observed transcriptional signatures associated with increased oxidative and cellular stress as well as oxidative phosphorylation in immature and mature myeloid progenitors. Single cell analysis of the chromatin landscape showed altered drivers of differentiation in monocytes and progenitors. Collectively, these data indicate that chronic ethanol drinking results in remodeling of the transcriptional and epigenetic landscapes of the bone marrow compartment leading to altered functions in the periphery.

Risk Factors of Severe COVID-19: A Review of Host, Viral and Environmental Factors

The clinical course and outcome of COVID-19 are highly variable, ranging from asymptomatic infections to severe disease and death. Understanding the risk factors of severe COVID-19 is relevant both in the clinical setting and at the epidemiological level. Here, we provide an overview of host, viral and environmental factors that have been shown or (in some cases) hypothesized to be associated with severe clinical outcomes. The factors considered in detail include the age and frailty, genetic polymorphisms, biological sex (and pregnancy), co- and superinfections, non-communicable comorbidities, immunological history, microbiota, and lifestyle of the patient; viral genetic variation and infecting dose; socioeconomic factors; and air pollution. For each category, we compile (sometimes conflicting) evidence for the association of the factor with COVID-19 outcomes (including the strength of the effect) and outline possible action mechanisms. We also discuss the complex interactions between the various risk factors.

RNA biomarkers for alcohol use disorder

Alcohol use disorder (AUD) is highly prevalent and one of the leading causes of disability in the US and around the world. There are some molecular biomarkers of heavy alcohol use and liver damage which can suggest AUD, but these are lacking in sensitivity and specificity. AUD treatment involves psychosocial interventions and medications for managing alcohol withdrawal, assisting in abstinence and reduced drinking (naltrexone, acamprosate, disulfiram, and some off-label medications), and treating comorbid psychiatric conditions (e.g., depression and anxiety). It has been suggested that various patient groups within the heterogeneous AUD population would respond more favorably to specific treatment approaches. For example, there is some evidence that so-called reward-drinkers respond better to naltrexone than acamprosate. However, there are currently no objective molecular markers to separate patients into optimal treatment groups or any markers of treatment response. Objective molecular biomarkers could aid in AUD diagnosis and patient stratification, which could personalize treatment and improve outcomes through more targeted interventions. Biomarkers of treatment response could also improve AUD management and treatment development. Systems biology considers complex diseases and emergent behaviors as the outcome of interactions and crosstalk between biomolecular networks. A systems approach that uses transcriptomic (or other -omic data, e.g., methylome, proteome, metabolome) can capture genetic and environmental factors associated with AUD and potentially provide sensitive, specific, and objective biomarkers to guide patient stratification, prognosis of treatment response or relapse, and predict optimal treatments. This Review describes and highlights state-of-the-art research on employing transcriptomic data and artificial intelligence (AI) methods to serve as molecular biomarkers with the goal of improving the clinical management of AUD. Considerations about future directions are also discussed.

Alcohol Drinking Patterns and Laboratory Indices of Health: Does Type of Alcohol Preferred Make a Difference?

Although excessive alcohol consumption is a highly prevalent public health problem the data on the associations between alcohol consumption and health outcomes in individuals preferring different types of alcoholic beverages has remained unclear. We examined the relationships between the amounts and patterns of drinking with the data on laboratory indices of liver function, lipid status and inflammation in a national population-based health survey (FINRISK). Data on health status, alcohol drinking, types of alcoholic beverages preferred, body weight, smoking, coffee consumption and physical activity were recorded from 22,432 subjects (10,626 men, 11,806 women), age range 25-74 years. The participants were divided to subgroups based on the amounts of regular alcohol intake (abstainers, moderate and heavy drinkers), patterns of drinking (binge or regular) and the type of alcoholic beverage preferred (wine, beer, cider or long drink, hard liquor or mixed). Regular drinking was found to be more typical in wine drinkers whereas the subjects preferring beer or hard liquor were more often binge-type drinkers and cigarette smokers. Alcohol use in all forms was associated with increased frequencies of abnormalities in the markers of liver function, lipid status and inflammation even at rather low levels of consumption. The highest rates of abnormalities occurred, however, in the subgroups of binge-type drinkers preferring beer or hard liquor. These results demonstrate that adverse consequences of alcohol occur even at moderate average drinking levels especially in individuals who engage in binge drinking and in those preferring beer or hard liquor. Further emphasis should be placed on such patterns of drinking in policies aimed at preventing alcohol-induced adverse health outcomes.

Blood Cell Responses Following Heavy Alcohol Consumption Coincide with Changes in Acute Phase Reactants of Inflammation, Indices of Hemolysis and Immune Responses to Ethanol Metabolites

Aberrations in blood cells are common among heavy alcohol drinkers. In order to shed further light on such responses, we compared blood cell status with markers of hemolysis, mediators of inflammation and immune responses to ethanol metabolites in alcohol-dependent patients at the time of admission for detoxification and after abstinence. Blood cell counts, indices of hemolysis (LDH, haptoglobin, bilirubin), calprotectin (a marker of neutrophil activation), suPAR, CD163, pro- and anti-inflammatory cytokines and autoantibodies against protein adducts with acetaldehyde, the first metabolite of ethanol, were measured from alcohol-dependent patients (73 men, 26 women, mean age 43.8 ± 10.4 years) at baseline and after 8 ± 1 days of abstinence. The assessments also included information on the quantities of alcohol drinking and assays for biomarkers of alcohol consumption (CDT), liver function (AST, ALT, ALP, GGT) and acute phase reactants of inflammation. At baseline, the patients showed elevated values of CDT and biomarkers of liver status, which decreased significantly during abstinence. A significant decrease also occurred in LDH, bilirubin, CD163 and IgA and IgM antibodies against acetaldehyde adducts, whereas a significant increase was noted in blood leukocytes, platelets, MCV and suPAR levels. The changes in blood leukocytes correlated with those in serum calprotectin (p < 0.001), haptoglobin (p < 0.001), IL-6 (p < 0.02) and suPAR (p < 0.02). The changes in MCV correlated with those in LDH (p < 0.02), MCH (p < 0.01), bilirubin (p < 0.001) and anti-adduct IgG (p < 0.01). The data indicates that ethanol-induced changes in blood leukocytes are related with acute phase reactants of inflammation and release of neutrophil calprotectin. The studies also highlight the role of hemolysis and immune responses to ethanol metabolites underlying erythrocyte abnormalities in alcohol abusers.

Paternal alcohol exposures program intergenerational hormetic effects on offspring fetoplacental growth

Hormesis refers to graded adaptive responses to harmful environmental stimuli where low-level toxicant exposures stimulate tissue growth and responsiveness while, in contrast, higher-level exposures induce toxicity. Although the intergenerational inheritance of programmed hormetic growth responses is described in plants and insects, researchers have yet to observe this phenomenon in mammals. Using a physiologically relevant mouse model, we demonstrate that chronic preconception paternal alcohol exposures program nonlinear, dose-dependent changes in offspring fetoplacental growth. Our studies identify an inverse j-shaped curve with a threshold of 2.4 g/Kg per day; below this threshold, paternal ethanol exposures induce programmed increases in placental growth, while doses exceeding this point yield comparative decreases in placental growth. In male offspring, higher paternal exposures induce dose-dependent increases in the placental labyrinth layer but do not impact fetal growth. In contrast, the placental hypertrophy induced by low-level paternal ethanol exposures associate with increased offspring crown-rump length, particularly in male offspring. Finally, alterations in placental physiology correlate with disruptions in both mitochondrial-encoded and imprinted gene expression. Understanding the influence of ethanol on the paternally-inherited epigenetic program and downstream hormetic responses in offspring growth may help explain the enormous variation observed in fetal alcohol spectrum disorder (FASD) phenotypes and incidence.

Metabolomic predictors of phenotypic traits can replace and complement measured clinical variables in population-scale expression profiling studies

Population-scale expression profiling studies can provide valuable insights into biological and disease-underlying mechanisms. The availability of phenotypic traits is essential for studying clinical effects. Therefore, missing, incomplete, or inaccurate phenotypic information can make analyses challenging and prevent RNA-seq or other omics data to be reused. A possible solution are predictors that infer clinical or behavioral phenotypic traits from molecular data. While such predictors have been developed based on different omics data types and are being applied in various studies, metabolomics-based surrogates are less commonly used than predictors based on DNA methylation profiles.In this study, we inferred 17 traits, including diabetes status and exposure to lipid medication, using previously trained metabolomic predictors. We evaluated whether these metabolomic surrogates can be used as an alternative to reported information for studying the respective phenotypes using expression profiling data of four population cohorts. For the majority of the 17 traits, the metabolomic surrogates performed similarly to the reported phenotypes in terms of effect sizes, number of significant associations, replication rates, and significantly enriched pathways.The application of metabolomics-derived surrogate outcomes opens new possibilities for reuse of multi-omics data sets. In studies where availability of clinical metadata is limited, missing or incomplete information can be complemented by these surrogates, thereby increasing the size of available data sets. Additionally, the availability of such surrogates could be used to correct for potential biological confounding. In the future, it would be interesting to further investigate the use of molecular predictors across different omics types and cohorts.

Ethanol Consumption Induces Nonspecific Inflammation and Functional Defects in Alveolar Macrophages

Chronic alcohol drinking is associated with increased susceptibility to viral and bacterial respiratory pathogens. In this study, we use a rhesus macaque model of voluntary ethanol self-administration to study the effects of long-term alcohol drinking on the immunological landscape of the lung. We report a heightened inflammatory state in alveolar macrophages (AMs) obtained from ethanol (EtOH)-drinking animals that is accompanied by increased chromatin accessibility in intergenic regions that regulate inflammatory genes and contain binding motifs for transcription factors AP-1, IRF8, and NFKB p-65. In line with these transcriptional and epigenetic changes at the basal state, AMs from EtOH-drinking animals generate elevated inflammatory mediator responses to lipopolysaccharides and respiratory syncytial virus. However, the transcriptional analysis revealed an inefficient induction of interferon-stimulated genes with EtOH in response to the respiratory syncytial virus, suggesting disruption of antimicrobial defenses. Correspondingly, AMs from EtOH-drinking animals exhibited transcriptional shifts indicative of increased oxidative stress and oxidative phosphorylation, which was coupled with higher cytosolic reactive oxygen species and mitochondrial potential. This heightened oxidative stress state was accompanied by decreased ability to phagocytose bacteria. Bulk RNA and assay for transposase-accessible chromatin sequencing data further revealed reduced expression and chromatin accessibility of loci associated with tissue repair and maintenance with chronic EtOH drinking. Similarly, analysis of single-cell RNA sequencing data revealed shifts in cell states from tissue maintenance to inflammatory responses with EtOH. Collectively, these data provide novel insight into mechanisms by which chronic EtOH drinking increases susceptibility to infection in patients with alcohol use disorders.

A new monocyte epigenetic clock reveals nonlinear effects of alcohol consumption on biological aging in three independent cohorts (N = 2242)

BACKGROUND

Assessing the effect of alcohol consumption on biological age is essential for understanding alcohol use-related comorbidities and mortality. Previously developed epigenetic clocks are mainly based on DNA methylation in heterogeneous cell types, which provide limited knowledge on the impacts of alcohol consumption at the individual cellular level. Evidence shows that monocytes play an important role in both alcohol-induced pathophysiology and the aging process. In this study, we developed a novel monocyte-based DNA methylation clock (MonoDNAmAge) to assess the impact of alcohol consumption on monocyte age.

METHODS

A machine learning method was applied to select a set of chronological age-associated DNA methylation CpG sites from 1202 monocyte methylomes. Pearson correlation was tested between MonoDNAmAge and chronological age in three independent cohorts (N_total  = 2242). Using the MonoDNAmAge clock and four established clocks (i.e., HorvathDNAmAge, HannumDNAmAge, PhenoDNAmAge, GrimDNAmAge), we then evaluated the effect of alcohol consumption on epigenetic aging in the three cohorts [i.e., Yale Stress Center Community Study (YSCCS), Veteran Aging Cohort Study (VACS), Women's Interagency HIV Study (WIHS)] using linear and quadratic models.

RESULTS

The MonoDNAmAge, comprised of 186 CpG sites, was moderately to strongly correlated with chronological age in the three cohorts (r = 0.90, p = 3.12E-181 in YSCCS; r = 0.54, p = 1.75E-96 in VACS; r = 0.66, p = 1.50E-60 in WIHS). More importantly, we found a nonlinear association between MonoDNAmAge and alcohol consumption (p_model  = 4.55E-08, px2  = 7.80E-08 in YSCCS; p_model  = 1.85E-02, px2  = 3.46E-02 in VACS). Heavy alcohol consumption increased EAA_MonoDNAmAge up to 1.60 years while light alcohol consumption decreased EAA_MonoDNAmAge up to 2.66 years. These results were corroborated by the four established epigenetic clocks (i.e., HorvathDNAmAge, HannumDNAmAge, PhenoDNAmAge, GrimDNAmAge).

CONCLUSIONS

The results suggest a nonlinear relationship between alcohol consumption and its effects on epigenetic age. Considering adverse effects of alcohol consumption on health, nonlinear effects of alcohol use should be interpreted with caution. The findings, for the first time, highlight the complex effects of alcohol consumption on biological aging.

Prenatal and adolescent alcohol exposure programs immunity across the lifespan: CNS-mediated regulation

For many individuals, first exposure to alcohol occurs either prenatally due to maternal drinking, or during adolescence, when alcohol consumption is most likely to be initiated. Prenatal Alcohol Exposure (PAE) and its associated Fetal Alcohol Spectrum Disorders (FASD) in humans is associated with earlier initiation of alcohol use and increased rates of Alcohol Use Disorders (AUD). Initiation of alcohol use and misuse in early adolescence correlates highly with later AUD diagnosis as well. Thus, PAE and adolescent binge drinking set the stage for long-term health consequences due to adverse effects of alcohol on subsequent immune function, effects that may persist across the lifespan. The overarching goal of this review, therefore, is to determine the extent to which early developmental exposure to alcohol produces long-lasting, and potentially life-long, changes in immunological function. Alcohol affects the whole body, yet most studies are narrowly focused on individual features of immune function, largely ignoring the systems-level interactions required for effective host defense. We therefore emphasize the crucial role of the Central Nervous System (CNS) in orchestrating host defense processes. We argue that alcohol-mediated disruption of host immunity can occur through both (a) direct action of ethanol on neuroimmune processes, that subsequently disrupt peripheral immune function (top down); and (b) indirect action of ethanol on peripheral immune organs/cells, which in turn elicit consequent changes in CNS neuroimmune function (bottom up). Recognizing that alcohol consumption across the entire body, we argue in favor of integrative, whole-organism approaches toward understanding alcohol effects on immune function, and highlight the need for more work specifically examining long-lasting effects of early developmental exposure to alcohol (prenatal and adolescent periods) on host immunity.

Chronic Alcohol Exposure Among People Living with HIV Is Associated with Innate Immune Activation and Alterations in Monocyte Phenotype and Plasma Cytokine Profile

Despite advances in antiretroviral therapy, chronic immune activation continues to be observed among individuals with well-controlled HIV viral loads, and is associated with non-AIDS defining morbidities among people living with HIV. Alcohol use disorder impacts a significant proportion of individuals living with HIV, and alcohol exposure is known to damage the intestinal epithelium which may increase translocation of pathogens and their molecular products, driving systemic immune activation and dysregulation. The aim of this study was to determine if adults living with HIV with well-controlled viral loads, who also suffer from alcohol use disorder with and without hepatitis C virus co-infection (n=23), exhibit evidence of advanced systemic immune activation, intestinal damage, and microbial translocation, as compared to adults living with HIV who are not exposed to chronic alcohol or other substances of abuse (n=29). The impact of a 1-month intervention to treat alcohol-use disorder was also examined. Alcohol-use disorder was associated with evidence of advanced innate immune activation, alterations in monocyte phenotype including increased expression of Toll-like receptor 4, increased burden of stimulatory ligands for Toll-like receptor 4, and alterations in plasma cytokine signature, most notably elevations in soluble CD40 ligand and transforming growth factor beta. Alcohol-associated immune activation was more pronounced among individuals with hepatitis C virus co-infection. Although the 1-month intervention to treat alcohol use disorder did not result in significant reductions in the interrogated indicators of immune activation, our findings suggest that chronic alcohol exposure is a major modifiable risk factor for chronic immune activation and dysregulation among people-living with HIV.

Synaptic effects of IL-1β and CRF in the central amygdala after protracted alcohol abstinence in male rhesus macaques

A major barrier to remission from an alcohol use disorder (AUD) is the continued risk of relapse during abstinence. Assessing the neuroadaptations after chronic alcohol and repeated abstinence is important to identify mechanisms that may contribute to relapse. In this study, we used a rhesus macaque model of long-term alcohol use and repeated abstinence, providing a platform to extend mechanistic findings from rodents to primates. The central amygdala (CeA) displays elevated GABA release following chronic alcohol in rodents and in abstinent male macaques, highlighting this neuroadaptation as a conserved mechanism that may underlie excessive alcohol consumption. Here, we determined circulating interleukin-1β (IL-1β) levels, CeA transcriptomic changes, and the effects of IL-1β and corticotropin releasing factor (CRF) signaling on CeA GABA transmission in male controls and abstinent drinkers. While no significant differences in peripheral IL-1β or the CeA transcriptome were observed, pathway analysis identified several canonical immune-related pathways. We addressed this potential dysregulation of CeA immune signaling in abstient drinkers with an electrophysiological approach. We found that IL-1β decreased CeA GABA release in controls while abstinent drinkers were less sensitive to IL-1β's effects, suggesting adaptations in the neuromodulatory role of IL-1β. In contrast, CRF enhanced CeA GABA release similarly in controls and abstinent drinkers, consistent with rodent studies. Notably, CeA CRF expression was inversely correlated with intoxication, suggesting that CRF levels during abstinence may predict future intoxication. Together, our findings highlight conserved and divergent actions of chronic alcohol on neuroimmune and stress signaling on CeA GABA transmission across rodents and macaques.

Alcohol-Associated Tissue Injury: Current Views on Pathophysiological Mechanisms

At-risk alcohol use is a major contributor to the global health care burden and leads to preventable deaths and diseases including alcohol addiction, alcoholic liver disease, cardiovascular disease, diabetes, traumatic injuries, gastrointestinal diseases, cancers, and fetal alcohol syndrome. Excessive and frequent alcohol consumption has increasingly been linked to alcohol-associated tissue injury and pathophysiology, which have significant adverse effects on multiple organ systems. Extensive research in animal and in vitro models has elucidated the salient mechanisms involved in alcohol-induced tissue and organ injury. In some cases, these pathophysiological mechanisms are shared across organ systems. The major alcohol- and alcohol metabolite-mediated mechanisms include oxidative stress, inflammation and immunometabolic dysregulation, gut leak and dysbiosis, cell death, extracellular matrix remodeling, endoplasmic reticulum stress, mitochondrial dysfunction, and epigenomic modifications. These mechanisms are complex and interrelated, and determining the interplay among them will make it possible to identify how they synergistically or additively interact to cause alcohol-mediated multiorgan injury. In this article, we review the current understanding of pathophysiological mechanisms involved in alcohol-induced tissue injury.

Profiling of extracellular vesicle-bound miRNA to identify candidate biomarkers of chronic alcohol drinking in nonhuman primates

BACKGROUND

Long-term alcohol drinking is associated with numerous health complications including susceptibility to infection, cancer, and organ damage. However, due to the complex nature of human drinking behavior, it has been challenging to identify reliable biomarkers of alcohol drinking behavior prior to signs of overt organ damage. Recently, extracellular vesicle-bound microRNAs (EV-miRNAs) have been found to be consistent biomarkers of conditions that include cancer and liver disease.

METHODS

In this study, we profiled the plasma EV-miRNA content by miRNA-Seq from 80 nonhuman primates after 12 months of voluntary alcohol drinking.

RESULTS

We identified a list of up- and downregulated EV-miRNA candidate biomarkers of heavy drinking and those positively correlated with ethanol dose. We overexpressed these candidate miRNAs in control primary peripheral immune cells to assess their potential functional mechanisms. We found that overexpression of miR-155, miR-154, miR-34c, miR-450a, and miR-204 led to increased production of the inflammatory cytokines TNFα or IL-6 in peripheral blood mononuclear cells after stimulation.

CONCLUSION

This exploratory study identified several EV-miRNAs that could serve as biomarkers of long-term alcohol drinking and provide a mechanism to explain alcohol-induced peripheral inflammation.

Transcriptional and Epigenetic Regulation of Monocyte and Macrophage Dysfunction by Chronic Alcohol Consumption

Drinking alcohol, even in moderation, can affect the immune system. Studies have shown disproportionate effects of alcohol on circulating and tissue-resident myeloid cells (granulocytes, monocytes, macrophages, dendritic cells). These cells orchestrate the body's first line of defense against microbial challenges as well as maintain tissue homeostasis and repair. Alcohol's effects on these cells are dependent on exposure pattern, with acute drinking dampening but chronic drinking enhancing production of inflammatory mediators. Although chronic drinking is associated with heightened systemic inflammation, studies on tissue resident macrophage populations in several organs including the spleen, liver, brain, and lung have also shown compromised functional and metabolic capacities of these cells. Many of these effects are thought to be mediated by oxidative stress caused by alcohol and its metabolites which can directly impact the cellular epigenetic landscapes. In addition, since myeloid cells are relatively short-lived in circulation and are under constant repopulation from the bone marrow compartment, alcohol's effects on bone marrow progenitors and hematopoiesis are important for understanding the impact of alcohol systemically on these myeloid populations. Alcohol-induced disruption of progenitor, circulating, and tissue resident myeloid populations contribute to the increased susceptibility of patients with alcohol use disorders to viral and bacterial infections. In this review, we provide an overview of the impact of chronic alcohol consumption on the function of monocytes and macrophages in host defense, tissue repair and inflammation. We then summarize our current understanding of the mechanisms underlying alcohol-induced disruption and examine changes in transcriptome and epigenome of monocytes and mcrophages. Overall, chronic alcohol consumption leads to hyper-inflammation concomitant with decreased microbial and wound healing responses by monocytes/macrophages due to a rewiring of the epigentic and transcriptional landscape. However, in advanced alcoholic liver disease, myeloid cells become immunosuppressed as a response to the surrounding hyper-inflammatory milieu. Therefore, the effect of chronic alcohol on the inflammatory response depends on disease state and the immune cell population.

Altered Fecal Microbiota Correlated With Systemic Inflammation in Male Subjects With Methamphetamine Use Disorder

Methamphetamine use disorder (MUD) is a major public health problem worldwide with limited effective treatment options. Previous studies have reported methamphetamine-associated alterations in gut microbiota. A potential role of gut microbiota in regulating methamphetamine-induced brain dysfunction through interactions with the host immune system has been proposed, but evidence for this hypothesis is limited. The present study aimed to investigate the alterations in the fecal microbiota and explore its relationship with systemic inflammation in MUD. Fecal samples were obtained from 26 male subjects with MUD and 17 sex- and age- matched healthy controls. Fecal microbial profiles were analyzed by 16S rRNA sequencing. Plasma inflammatory markers were measured using enzyme-linked immunosorbent assay. Associations between fecal microbiota, systemic inflammatory markers and clinical characteristics were examined by Spearman partial correlation analysis while controlling for possible confounders. Compared with healthy controls, individuals with MUD showed no difference in fecal microbial diversity, but exhibited differences in the relative abundance of several microbial taxa. At the genus level, a higher abundance of Collinsella, Odoribacter and Megasphaera and lower levels of Faecalibacterium, Blautia, Dorea and Streptococcus were detected in subjects with MUD. More importantly, altered fecal microbiota was found to be correlated with plasma levels of CRP, IL-2, IL-6 and IL-10. The order Lactobacillales, exhibiting lower abundance in participants with MUD, was positively related to the duration of methamphetamine abstinence and the plasma level of anti-inflammatory cytokine IL-10. This study is the first to provide evidence for a link between altered fecal microbiota and systemic inflammation in MUD. Further elucidation of interactions between gut microbiota and the host immune system may be beneficial for the development of novel therapeutic approaches for MUD.

Alcohol exposure increases manganese accumulation in the brain and exacerbates manganese-induced neurotoxicity in mice

Environmental and occupational exposure to heavy metals remains one of the major concerns in public health. Increased levels of manganese (Mn) pollution are associated with profound neurotoxic effects, including neurobehavioral deficits and disturbances resembling Parkinson's disease. While Mn absorption is in part mediated by iron transporters, recent studies have shown that the levels of iron transporters are modified by alcohol and that chronic alcohol consumption increases body iron stores. However, it is largely unexplored whether alcohol exposure influences the transport and neurotoxicity of Mn. To address this question, we exposed mice to ethanol (10%; v/v) by drinking water for 4 weeks, during which period MnCl₂ (5 mg/kg) or saline solutions were administered daily by intranasal instillation. Ethanol consumption in mice increased brain Mn levels in a dose-dependent manner after Mn instillation, determined by inductively-coupled plasma mass spectrometry, which was accompanied by up-regulation of iron transporters, as assessed by western blotting and qPCR. In addition, alcohol drinking increased hypoxic response and decreased hepcidin expression, providing the molecular mechanism of increased iron transporters and Mn uptake upon alcohol consumption. Moreover, brain dopamine levels, analyzed by HPLC, were decreased after intranasal Mn instillation, which was worsened by alcohol. Likewise, alcohol-Mn co-exposure synergistically altered dopaminergic protein expression. Finally, alcohol binge-drinking, which resembles alcohol drinking manner in humans, increased brain Mn content along with upregulation of iron transporters. Our study suggests that individuals who consume alcohol may have a higher risk of Mn neurotoxicity upon Mn exposure.

Comparison of serum calprotectin, a marker of neutrophil activation, and other mediators of inflammation in response to alcohol consumption

AIMS

Previous studies have indicated that heavy alcohol intake stimulates inflammation and impairs the body's ability to regulate inflammation. The aim of this study was to compare changes in neutrophil calprotectin and a wide spectrum of other inflammatory mediators in response to heavy alcohol drinking.

METHODS

Serum calprotectin (a marker of neutrophil activation), suPAR, CD163, and pro- (IL-6, IL-8, TNF-α) and anti-inflammatory (IL-10, TGF-β) cytokines were measured from 61 alcohol-dependent subjects (46 men, 15 women, mean age 43.6 ± 11.0 years) at the time of admission for detoxification and after 8 ± 2 days of abstinence. These biomarkers were also measured from age- and sex-matched healthy controls representing abstainers or light drinkers. The clinical assessments included detailed clinical interviews on the amounts and patterns of alcohol consumption and assays for biomarkers of alcohol consumption (GGT, CDT, MCV, GGT-CDT) and liver function (AST, ALT).

RESULTS

The subjects with alcohol use disorder showed significantly higher concentrations of serum calprotectin (p < 0.0005), suPAR (p < 0.01), CD163 (p < 0.01), IL-6 (p < 0.0005), IL-8 (p < 0.0005), TNF-α (p < 0.001), and IL-10 (p < 0.0005) than healthy controls. These inflammatory mediators, except for CD163, remained elevated after the 8 ± 2-day period of supervised abstinence, which resulted in significant decreases in the biomarkers of alcohol consumption and indices of liver status. The AUC (0.855) for serum calprotectin in differentiating between the heavy drinkers and healthy controls was equal or equivalent with those of the conventional biomarkers of alcohol consumption (GGT:0.835 or CDT:0.803).

CONCLUSIONS

The data indicate that neutrophil calprotectin is released in response to heavy alcohol intake in a sensitive manner and may be associated with perpetuation of inflammation in patients with alcohol use disorder. Serum calprotectin may also prove to be a useful biomarker for inflammatory activity in alcohol-consuming patients.

Transcriptional, Epigenetic, and Functional Reprogramming of Monocytes From Non-Human Primates Following Chronic Alcohol Drinking

Chronic heavy drinking (CHD) of alcohol is a known risk factor for increased susceptibility to bacterial and viral infection as well as impaired wound healing. Evidence suggests that these defects are mediated by a dysregulated inflammatory response originating from myeloid cells, notably monocytes and macrophages, but the mechanisms remain poorly understood. Our ability to study CHD is impacted by the complexities of human drinking patterns and behavior as well as comorbidities and confounding risk factors for patients with alcohol use disorders. To overcome these challenges, we utilized a translational rhesus macaque model of voluntary ethanol self-administration that closely recapitulates human drinking patterns and chronicity. In this study, we examined the effects of CHD on blood monocytes in control and CHD female macaques after 12 months of daily ethanol consumption. While monocytes from CHD female macaques generated a hyper-inflammatory response to ex vivo LPS stimulation, their response to E. coli was dampened. In depth scRNA-Seq analysis of purified monocytes revealed significant shifts in classical monocyte subsets with accumulation of cells expressing markers of hypoxia (HIF1A) and inflammation (NFkB signaling pathway) in CHD macaques. The increased presence of monocyte subsets skewed towards inflammatory phenotypes was complemented by epigenetic analysis, which revealed higher accessibility of promoter regions that regulate genes involved in cytokine signaling pathways. Collectively, data presented in this manuscript demonstrate that CHD shifts classical monocyte subset composition and primes the monocytes towards a more hyper-inflammatory response to LPS, but compromised pathogen response.

Possible mechanisms of HIV neuro-infection in alcohol use: Interplay of oxidative stress, inflammation, and energy interruption

Alcohol use and HIV-1 infection have a pervasive impact on brain function, which extends to the requirement, distribution, and utilization of energy within the central nervous system. This effect on neuroenergetics may explain, in part, the exacerbation of HIV-1 disease under the influence of alcohol, particularly the persistence of HIV-associated neurological complications. The objective of this review article is to highlight the possible mechanisms of HIV/AIDS progression in alcohol users from the perspective of oxidative stress, neuroinflammation, and interruption of energy metabolism. These include the hallmark of sustained immune cell activation and high metabolic energy demand by HIV-1-infected cells in the central nervous system, with at-risk alcohol use. Here, we discussed the point that the increase in energy supply requirement by HIV-1-infected neuroimmune cells as well as the deterrence of nutrient uptake across the blood-brain barrier significantly depletes the energy source and neuro-environment homeostasis in the CNS. We also described the mechanistic idea that comorbidity of HIV-1 infection and alcohol use can cause a metabolic shift and redistribution of energy usage toward HIV-1-infected neuroimmune cells, as shown in neuropathological evidence. Under such an imbalanced neuro-environment, meaningless energy waste is expected in infected cells, along with unnecessary malnutrition in non-infected neuronal cells, which is likely to accelerate HIV neuro-infection progression in alcohol use. Thus, it will be important to consider the factor of nutrients/energy imbalance in formulating treatment strategies to help impede the progression of HIV-1 disease and associated neurological disorders in alcohol use.

The expression of FLNA and CLU in PBMCs as a novel screening marker for hepatocellular carcinoma

Early detection improves survival and increases curative probability in hepatocellular carcinoma (HCC). Peripheral blood mononuclear cells (PBMCs) can provide an inexpensive, less-invasive and highly accurate method. The objective of this study is to find the potential marker for HCC screening, utilizing gene expression of the PBMCs. Data from the NCBI GEO database of gene expression in HCC patients and healthy donor's PBMCs was collected. As a result, GSE 49515 and GSE 58208 were found. Using both, a statistical significance test was conducted in each gene expression of each data set which resulted in 187 genes. We randomized three selected genes (FLNA, CAP1, and CLU) from the significant p-value group (p-values < 0.001). Then, a total of 76 healthy donors, 153 HCC, 20 hepatic fibrosis, 20 non-alcoholic fatty liver were collected. Quantitative RT-PCR (qRT-PCR) was performed in cDNA from all blood samples from the qRT-PCR, The Cycle threshold (Ct) value of FLNA, CLU, CAP1 of HCC group (28.47 ± 4.43, 28.01 ± 3.75, 29.64 ± 3.90) were lower than healthy group (34.23 ± 3.54, 32.90 ± 4.15, 32.18 ± 5.02) (p-values < 0.0001). The accuracy, sensitivity and specificity of these genes as a screening tool were: FLNA (80.8%, 88.0%, 65.8%), CLU (63.4%, 93.3%, 31.3%), CAP1 (67.2%, 83.3%, 39.1%). The tests were performed in two and three gene combinations. Results demonstrated high accuracy of 86.2%, sensitivity of 85% and specificity of 88.4% in the FLNA and CLU combination. Furthermore, after analyzed using hepatic fibrosis and non-alcoholic fatty liver as a control, the FLNA and CLU combination is shown to have accuracy of 76.9%, sensitivity of 77.6% and specificity of 75%. Also, we founded that our gene combination performs better than the current gold standard for HCC screening. We concluded that FLNA and CLU combination have high potential for being HCC novel markers. Combined with current tumor markers, further research of the gene’s expression might help identify more potential markers and improve diagnosis methods.

The Immune System through the Lens of Alcohol Intake and Gut Microbiota

The human gut is the largest organ with immune function in our body, responsible for regulating the homeostasis of the intestinal barrier. A diverse, complex and dynamic population of microorganisms, called microbiota, which exert a significant impact on the host during homeostasis and disease, supports this role. In fact, intestinal bacteria maintain immune and metabolic homeostasis, protecting our organism against pathogens. The development of numerous inflammatory disorders and infections has been linked to altered gut bacterial composition or dysbiosis. Multiple factors contribute to the establishment of the human gut microbiota. For instance, diet is considered as one of the many drivers in shaping the gut microbiota across the lifetime. By contrast, alcohol is one of the many factors that disrupt the proper functioning of the gut, leading to a disruption of the intestinal barrier integrity that increases the permeability of the mucosa, with the final result of a disrupted mucosal immunity. This damage to the permeability of the intestinal membrane allows bacteria and their components to enter the blood tissue, reaching other organs such as the liver or the brain. Although chronic heavy drinking has harmful effects on the immune system cells at the systemic level, this review focuses on the effect produced on gut, brain and liver, because of their significance in the link between alcohol consumption, gut microbiota and the immune system.

Clinical vulnerability for severity and mortality by COVID-19 among users of alcohol and other substances

The COVID-19 pandemic is a public health emergency. Individuals with substance use disorder have a higher risk of infection and may suffer from more severe forms of the disease. Our goal is to investigate the prevalence of risk factors for COVID-19 severity in individuals with different substance use and explore whether specific types of substance are potentially associated with more clinical risk factors which could increase morbimortality in this population. The sample included 821 men hospitalized at an inpatient Addiction unit (305 alcohol users, 233 cocaine/crack users, and 283 multiusers). Data were collected using the Addiction Severity Index version 6. The most prevalent risk factors for COVID-19 severity observed in our sample were: smoking (82.5%), arterial hypertension (26.6%), respiratory problems (23.4%), and history of homelessness (25.1%). Arterial hypertension and cirrhosis occurred more frequently among alcohol users. Multiusers lived in the streets longer and had a higher prevalence of HIV than alcohol users. Overall, 28% of the sample had three or more risk factors. The frequency of risk factors was high and this scenario suggests that these individuals could be more susceptible to worse COVID-19 prognosis. Therefore, prevention strategies directed at specific characteristics of substance users merit attention during the pandemic.

Acute Alcohol Intoxication Modulates Monocyte Subsets and Their Functions in a Time-Dependent Manner in Healthy Volunteers

Background

Excessive alcohol intake is associated with adverse immune response-related effects, however, acute and chronic abuse differently modulate monocyte activation. In this study, we have evaluated the phenotypic and functional changes of monocytes in acutely intoxicated healthy volunteers (HV).

Methods

Twenty-two HV consumed individually adjusted amounts of alcoholic beverages until reaching a blood alcohol level of 1‰ after 4h (T4). Peripheral blood was withdrawn before and 2h (T2), 4h (T4), 6h (T6), 24h (T24), and 48h (T48) after starting the experiment and stained for CD14, CD16 and TLR4. CD14^brightCD16^-, CD14^brightCD16⁺ and CD14^dimCD16⁺ monocyte subsets and their TLR4 expression were analyzed by flow cytometry. Inflammasome activation via caspase-1 in CD14⁺ monocytes was measured upon an ex vivo in vitro LPS stimulation. Systemic IL-1β and adhesion capacity of isolated CD14⁺ monocytes upon LPS stimulation were evaluated.

Results

The percentage of CD14⁺ monocyte did not change following alcohol intoxication, whereas CD14^brightCD16^- monocyte subset significantly increased at T2 and T24, CD14^brightCD16⁺ at T2, T4 and T6 and CD14^dimCD16⁺ at T4 and T6. The relative fraction of TLR4 expressing CD14⁺ monocytes as well as the density of TLR4 surface presentation increased at T2 and decreased at T48 significantly. TLR4⁺CD14⁺ monocytes were significantly enhanced in all subsets at T2. TLR4 expression significantly decreased in CD14^brightCD16^- at T48, in CD14^brightCD16⁺ at T24 and T48, increased in CD14^dimCD16⁺ at T2. IL-1β release upon LPS stimulation decreased at T48, correlating with TLR4 receptor expression. Alcohol downregulated inflammasome activation following ex vivo in vitro stimulation with LPS between T2 and T48 vs. T0. The adhesion capacity of CD14⁺ monocytes decreased from T2 with significance at T4, T6 and T48. Following LPS administration, a significant reduction of adhesion was observed at T4 and T6.

Conclusions

Alcohol intoxication immediately redistributes monocyte subsets toward the pro-inflammatory phenotype with their subsequent differentiation into the anti-inflammatory phenotype. This is paralleled by a significant functional depression, suggesting an alcohol-induced time-dependent hyporesponsiveness of monocytes to pathogenic triggers.

COVID-19 pandemic and alcohol consumption: Impacts and interconnections

Alcohol consumption is associated with multiple diseases and might contribute to vulnerability to SARS-CoV-2 infection. It can also catalyze exacerbations of mental and organic illnesses and predispose to behaviors with an increased risk of infection, severity of disease but also independently of sociopathic behavior and violence. Globally, millions of premature deaths from excessive alcohol consumption occur each year. This paper discusses the effects of increased alcohol consumption and the most important consequences on the health of the population during the social isolation and lockdown during current COVID-19 pandemic.

Immunological Disturbances and Neuroimaging Findings in Major Depressive Disorder (MDD) and Alcohol Use Disorder (AUD) Comorbid Patients

Mood disorders and Major Depressive Disorder, in particular, appear to be some of the most common psychiatric disorders with a high rate of comorbidity most frequently of anxiety or substance abuse disorders (alcohol use disorder). In both cases - MDD and AUD, a number of immunological disturbances are observed, such as chronic mild inflammation response, increased level of cytokines, hypercortisolaemia, which lead to specific changes in brain neurotransmitter functions. Some of the contemporary brain imaging techniques are functional magnetic resonance imaging (fMRI) and magnetic spectroscopy which are most commonly used to assess the brain metabolism and functional connectivity changes such as altered responses to emotional stimuli in MDD or overactivation of ventromedial prefrontal areas during delayed and underactivation of dorsolateral prefrontal regions during impulsive reward decisions in AUD and dysfunction of gamma-aminobutyric acid (GABA) and/or glutamate neurotransmitter systems, low NAA and myo-Inositol in both MDD and AUD.

Exploring the multifocal role of phytochemicals as immunomodulators

A well-functioning immune system of the host body plays pivotal role in the maintenance of ordinary physiological and immunological functions as well as internal environment. Balanced immunity enhances defense mechanism against infection, diseases and unwanted pathogens to avoid hypersensitivity reactions and immune related diseases. The ideal immune responses are the results of corrective interaction between the innate immune cells and acquired components of the immune system. Recently, the interest towards the immune system increased as significant target of toxicity due to exposure of chemicals, drugs and environmental pollutants. Numerous factors are involved in altering the immune responses of the host such as sex, age, stress, malnutrition, alcohol, genetic variability, life styles, environmental-pollutants and chemotherapy exposure. Immunomodulation is any modification of immune responses, often involved induction, amplification, attenuation or inhibition of immune responses. Several synthetic or traditional medicines are available in the market which promptly have many serious adverse effects and create pathogenic resistance. Phytochemicals are naturally occurring molecules, which significantly play an imperative role in modulating favorable immune responses. The present review emphasizes on the risk factors associated with alterations in immune responses, and immunomodulatory activity of phytochemicals specifically, glycosides, alkaloids, phenolic acids, flavonoids, saponins, tannins and sterols and sterolins.

Functionally Diverse Inflammatory Responses in Peripheral and Liver Monocytes in Alcohol-Associated Hepatitis

Alcohol‐associated hepatitis (AH) is an acute inflammatory disease in which gut‐microbial byproducts enter circulation and peripheral immune cells infiltrate the liver, leading to nonresolving inflammation and injury. Single‐cell RNA sequencing of peripheral blood mononuclear cells isolated from patients with AH and healthy controls paired with lipopolysaccharide (LPS) challenge revealed how diverse monocyte responses are divided among individual cells and change in disease. After LPS challenge, one monocyte subtype expressed pro‐inflammatory genes in both disease and healthy controls, while another monocyte subtype was anti‐inflammatory in healthy controls but switched to pro‐inflammatory in AH. Numerous immune genes are clustered within genomic cassettes, including chemokines and C‐type lectin receptors (CTRs). CTRs sense byproducts of diverse microbial and host origin. Single‐cell data revealed correlated expression of genes within cassettes, thus further diversifying different monocyte responses to individual cells. Monocyte up‐regulation of CTRs in response to LPS caused hypersensitivity to diverse microbial and host‐derived byproducts, indicating a secondary immune surveillance pathway up‐regulated in a subset of cells by a closely associated genomic cassette. Finally, expression of CTR genes was higher in livers of patients with severe AH, but not other chronic liver diseases, implicating secondary immune surveillance in nonresolving inflammation in severe AH.

The COVID-19 pandemic and its impact on substance use: Implications for prevention and treatment

The COVID-19 pandemic has brought major challenges to healthcare systems and public health policies globally, as it requires novel treatment and prevention strategies to adapt for the impact of the pandemic. Individuals with substance user disorders (SUD) are at risk population for contamination due to multiple factors-attributable to their clinical, psychological and psychosocial conditions. Moreover, social and economic changes caused by the pandemic, along with the traditional difficulties regarding treatment access and adherence-will certainly worsen during this period, therefore aggravate their condition. In addition, this population are potential vectors of transmission. In that sense, specific strategies for prevention and treatment must be discussed. health care professionals dealing with SUD must be aware of the risks and challenges they will meet during and after the COVID-19 outbreak. Addiction care must be reinforced, instead of postponed, in order to avoid complications of both SUD and COVID-19 and to prevent the transmission of coronavirus.

Restricted immunological and cellular pathways are shared by murine models of chronic alcohol consumption

Murine models of chronic alcohol consumption are frequently used to investigate alcoholic liver injury and define new therapeutic targets. Lieber-DeCarli diet (LD) and Meadows-Cook diet (MC) are the most accepted models of chronic alcohol consumption. It is unclear how similar these models are at the cellular, immunologic, and transcriptome levels. We investigated the common and specific pathways of LD and MC models. Livers from LD and MC mice were subjected to histologic changes, hepatic leukocyte population, hepatic transcripts level related to leukocyte recruitment, and hepatic RNA-seq analysis. Cross-species comparison was performed using the alcoholic liver disease (ALD) transcriptomic public dataset. Despite LD mice have increased liver injury and steatosis by alcohol exposure, the number of CD45⁺ cells were reduced. Opposite, MC mice have an increased number of monocytes/liver by alcohol. The pattern of chemokine gradient, adhesion molecules, and cytokine transcripts is highly specific for each model, not shared with advanced human alcoholic liver disease. Moreover, hepatic RNA-seq revealed a limited and restricted number of shared genes differentially changed by alcohol exposure in these 2 models. Thus, mechanisms involved in alcohol tissue injury are model-dependent at multiple levels and raise the consideration of significant pathophysiological diversity of human alcoholic liver injury.

Ethanol and its metabolites: update on toxicity, benefits, and focus on immunomodulatory effects

This article summarizes recent experimental and epidemiological data on the toxic and beneficial effects of ethanol and its metabolites (acetaldehyde), and focuses on their immunomodulatory effects. The section dealing with the toxic effects of alcohol focuses on its chronic toxicity (liver disorders, carcinogenic effects, cardiovascular disorders, neuropsychic disorders, addiction and withdrawal syndrome, hematologic disorders, reprotoxicity, osteoporosis) although acute toxicity is considered. The role of oxidative metabolism of ethanol by alcohol dehydrogenase, cytochrome P450 2E1, and aldehyde dehydrogenase, as well as the impact of genetic polymorphism in its physiopathology are also highlighted. The section dealing with the beneficial effects of low to moderate alcohol consumption (on cardiovascular system, diabetes, the nervous system and sensory organs, autoimmune diseases, and rheumatology) highlights the importance of anti-inflammatory and immunomodulatory effects in these observations. This knowledge, enriched by a focus on the immunomodulatory effects of ethanol and its metabolites, in particular on the NLRP3 inflammasome pathway, might facilitate the development of treatments that can reduce ethanol's harmful effects or accentuate its beneficial effects.