The neuropathology of alcohol-related brain damage

A network pharmacology approach and experimental validation to investigate the neuroprotective mechanism of quercetin against alcoholic brain injury via the JNK/P38 MAPK signaling pathway

OBJECTIVE

Alcoholic brain damage (ABD) is a progressive neurodegenerative disorder resulting from prolonged and excessive alcohol consumption, characterized by neuronal injury and cognitive decline. Currently, effective therapeutic strategies remain limited. Quercetin, a natural flavonoid, has demonstrated robust antioxidative, anti-inflammatory, and neuroprotective properties, suggesting its potential utility in ABD management. This study aimed to elucidate the molecular mechanisms underlying quercetin's therapeutic effects on ABD, specifically focusing on its regulatory role in the JNK/P38 MAPK signaling pathway, a critical mediator involved in neuroinflammation and apoptosis. Our findings provide mechanistic insights into the protective effects of quercetin and underscore its promise as a novel therapeutic agent targeting neuronal injury pathways associated with alcoholic brain damage.

METHODS

The components and targets of QE and ABD were identified from multiple databases, and potential targets and pathways were predicted using protein-protein interaction (PPI) network analysis and pathway enrichment analysis. Molecular docking was then employed to validate the predicted results. In vivo, an EtOH-induced ABD rat model was established, while in vitro, EtOH-induced BV2 microglial cells were used to investigate the anti-inflammatory and anti-apoptotic effects of QE. The potential mechanisms of QE were further validated through both in vivo and in vitro experiments.

RESULTS

KEGG analysis indicated that the JNK/P38 MAPK signaling pathway is likely associated with the protective effects of QE against ABD. Molecular docking results demonstrated that QE effectively binds to key proteins. QE significantly reduced brain tissue damage in ABD rats, and molecular biology analyses revealed that QE inhibited the protein expression of inflammatory cytokines in ABD and reduced oxidative stress levels in BV2 cells. Additionally, QE markedly decreased the protein expression levels of phosphorylated JNK and P38.

CONCLUSION

The study results indicate that QE significantly mitigates the progression and severity of alcoholic brain damage (ABD), with its anti-inflammatory and neuroprotective effects associated with the downregulation of the JNK/P38 MAPK pathway.

Phenotypic and Functional Alterations in Peripheral Blood Mononuclear Cell-Derived Microglia in a Primate Model of Chronic Alcohol Consumption

Alcohol-induced dysregulation of microglial activity is associated with neuroinflammation, cognitive decline, heightened risk for neurodegenerative diseases, alcohol dependence, and escalation of alcohol drinking. Given the challenge of longitudinally sampling primary microglia, we optimized an in vitro method to differentiate peripheral blood mononuclear cells (PBMC) from non-human primates (NHP) into microglia-like cells (induced-microglia; iMGL). The iMGLs displayed transcriptional profiles distinct from those of monocyte progenitors and closely resembling those of primary microglia. Notably, morphological features showed that differentiated iMGLs derived from NHPs with chronic alcohol consumption (CAC) possessed a more mature-like microglial morphology. Additionally, dysregulation in key inflammatory and regulatory markers alongside increased baseline phagocytic activity was observed in CAC-derived IMGLs in the resting state. Phenotypic and functional assessments following LPS stimulation indicated the presence of an immune-tolerant phenotype and enrichment of a CD86+ hyper-inflammatory subpopulation in iMGLs derived from ethanol-exposed animals. Collectively, these findings demonstrate that in vitro differentiation of PBMC offers a minimally invasive approach to studying the impact of CAC on microglial function revealing that CAC reshapes both functional and transcriptional profiles of microglia.

The liver-brain axis under the influence of chronic Opisthorchis felineus infection combined with prolonged alcoholization in mice

Our purpose was to model a combination of a prolonged consumption of ethanol with Opisthorchis felineus infection in mice. Four groups of C57BL/6 mice were compiled: OF, mice infected with O. felineus for 6 months; Eth, mice consuming 20 % ethanol; Eth+OF, mice subjected to both adverse factors; and CON, control mice not exposed to these factors. In the experimental mice, especially in Eth+OF, each treatment caused well-pronounced periductal and cholangiofibrosis, proliferation of bile ducts, and enlargement of areas of inflammatory infiltration in the liver parenchyma. Simultaneously with liver disintegration, the infectious factor caused - in the frontal cerebral cortex - the growth of pericellular edema (OF mice), which was attenuated by the administration of ethanol (Eth+OF mice). Changes in the levels of some proteins (Iba1, IL-1β, IL-6, and TNF) and in mRNA expression of genes Aif1, Il1b, Il6, and Tnf were found in the hippocampus and especially in the frontal cortex, implying region-specific neuroinflammation. Behavioral testing of mice showed that ethanol consumption influenced the behavior of Eth and Eth+OF mice in the forced swimming test and their startle reflex. In the open field test, more pronounced changes were observed in OF mice. In mice of all three experimental groups, especially in OF mice, a disturbance in the sense of smell was detected (fresh peppermint leaves). The results may reflect an abnormality of regulatory mechanisms of the central nervous system as a consequence of systemic inflammation under the combined action of prolonged alcohol consumption and helminth infection.

Comparative Analysis of Blood MMP-9 Concentration in Alcohol- and Opioid-Addicted Patients

BACKGROUND/OBJECTIVES

In brain physiology and disease, MMP-9 is a significant and apparently peculiar factor. Numerous studies have implicated neuroinflammatory processes involving MMP-9 in the pathophysiology of addiction. This study aims to evaluate plasma MMP-9 level as a biomarker for the stages of alcohol and opioid addiction.

METHODS

The case subjects were patients with opioid and alcohol addiction. The quantitative assessment of MMP-9 plasma concentration was performed using monoclonal antibodies against human MMP-9.

RESULTS

MMP-9 levels in the plasma of patients with alcohol and opioid dependence differ from MMP-9 concentrations in apparently healthy donors. During the intoxication stage, MMP-9 concentrations in individuals with alcohol and opioid dependence are similar and higher than in the control group. While the MMP-9 level is close to the control level after alcohol withdrawal, it stays increased during opioid withdrawal. When MMP-9 levels in plasma were measured in three distinct intoxicated states (light, moderate, and heavy) in cases of alcohol addiction, the results were all similar. Two distinct opioid intoxicated states (methadone and buprenorphine) and three withdrawals-following methadone, buprenorphine, and heroin abuse-were associated with high MMP-9 levels.

Vitamin Bs as Potent Anticancer Agents through MMP-2/9 Regulation

In recent years, the role of coenzymes, particularly those from the vitamin B group in modulating the activity of metalloenzymes has garnered significant attention in cancer treatment strategies. Metalloenzymes play pivotal roles in various cellular processes, including DNA repair, cell signaling, and metabolism, making them promising targets for cancer therapy. This review explores the complex interplay between coenzymes, specifically vitamin Bs, and metalloenzymes in cancer pathogenesis and treatment. Vitamins are an indispensable part of daily life, essential for optimal health and well-being. Beyond their recognized roles as essential nutrients, vitamins have increasingly garnered attention for their multifaceted functions within the machinery of cellular processes. In particular, vitamin Bs have emerged as a pivotal regulator within this intricate network, exerting profound effects on the functionality of metalloenzymes. Their ability to modulate metalloenzymes involved in crucial cellular pathways implicated in cancer progression presents a compelling avenue for therapeutic intervention. Key findings indicate that vitamin Bs can influence the activity and expression of metalloenzymes, thereby affecting processes such as DNA repair and cell signaling, which are critical in cancer development and progression. Understanding the mechanisms by which these coenzymes regulate metalloenzymes holds great promise for developing novel anticancer strategies. This review summarizes current knowledge on the interactions between vitamin Bs and metalloenzymes, highlighting their potential as anticancer agents and paving the way for innovative, cell-targeted cancer treatments.

Towards a Non-pharmacological Intervention on Apathy in Korsakoff's Syndrome: A Systematic Narrative Review Across Different Clinical Conditions

Abstract

Apathy is a quantitative reduction of goal-directed activity, which can be observed in relation to behavior, cognition, emotions and social interaction. It is an invalidating behavioral symptom that is frequently present across different psychiatric conditions and neurocognitive disorders including Korsakoff's Syndrome (KS). In fact, apathy is one of the most severe behavioral symptoms of KS and has a major impact on the lives of patients and their relatives and other informal caregivers. However, guidelines for the treatment of apathy in KS are currently not available. This systematic narrative review provides a transdiagnostic overview of the effectiveness of different types of non-pharmacological interventions on apathy across different study populations that at symptom-level share characteristics with KS. This evidence may inform the development of an intervention targeting apathy in KS. The included study populations are dementia (due to Alzheimer's disease, or vascular dementia), Parkinson's disease, schizophrenia and traumatic brain injury. Through a stepped selection approach and with regard to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 22 systematic reviews and 32 empirical articles on the non-pharmacological treatment of apathy were identified. The results show a variety of effective non-pharmacological interventions on apathy. In conditions with severe cognitive impairments, successful interventions did not rely on intrinsic motivation, self-monitoring, or illness insight of the patients, but depend on external stimulation and behavioral activation. Since apathy is a multidimensional construct, identification of the extent and type of apathetic behavior before starting an intervention is highly recommended. Furthermore, it is important to adjust the treatment to the patients' personal interests and needs and embedded in daily care.

Trial registration

CRD42022298464 (PROSPERO).

Association between alcohol consumption and incidence of dementia in current drinkers: linear and non-linear mendelian randomization analysis

Background

Previous conventional epidemiological studies found a J-shape relationship between alcohol consumption and dementia, but this result was subject to confounding biases and reverse causation. Therefore, we aimed to investigate the potential linear or non-linear causal association between alcohol consumption and the incident risk of dementia in current drinkers.

Methods

This study used data from the UK Biobank to investigate the relationship between alcohol consumption and dementia risk. 313,958 White British current drinkers, who were free of dementia during 2006-2010, were followed up until 2021. Alcohol consumption was self-reported and calculated according to the National Health Service guideline. The primary outcome was all-cause dementia identified through hospital and mortality records. We used multivariable Cox models with restricted cubic splines for conventional analysis and both non-linear and linear Mendelian Randomization (MR) analyses to assess causal relationships, employing a genetic score based on 95 SNPs identified from a meta-genome-wide association study of 941,280 people from Europe.

Findings

313,958 current drinkers consumed an average of 13.6 [IQR: 7.1-25.2] units/week alcohol (men averaged 20.2 [11.1-33.9] units/week and women 9.5 [5.3-16.7] units/week). During a mean follow-up of 13.2 years, 5394 (1.7%) developed dementia. Multivariable Cox model with restricted cubic spline functions identified a J-shaped relationship between alcohol consumption and dementia risk, with the lowest risk at 12.2 units/week. The non-linear MR failed to identify a significant non-linear causal relationship (p = 0.45). Both individual-level (HR: 2.22 95%CI [1.06-4.66]) and summary-level (1.89 [1.53-2.32]) linear MR analyses indicated that higher genetically predicted alcohol consumption increased dementia risk.

Interpretation

This study identified a positive linear causal relationship between alcohol consumption and dementia among current drinkers. The J-shaped association found in conventional epidemiological analysis was not supported by non-linear MR analyses. Our findings suggested that there was no safe level of alcohol consumption for dementia.

Funding

The Shenzhen Science and Technology Program and the Strategic Priority Research Program of Chinese Academy of Sciences.

Memantine alleviates cognitive impairment and hippocampal morphology injury in a mouse model of chronic alcohol exposure

Alcohol-related cognitive impairment (ARCI) is highly prevalent among patients with alcohol abuse and dependence. The pathophysiology of ARCI, pivotal for refined therapeutic approaches, is not fully elucidated, posing a risk of progression to severe neurological sequelae such as Korsakoff's syndrome (KS) and Alcohol-Related Dementia (ARD). This study ventures into the underlying mechanisms of chronic alcohol-induced neurotoxicity, notably glutamate excitotoxicity and cytoskeletal disruption, and explores the therapeutic potential of Memantine, a non-competitive antagonist of the N-methyl-d-aspartate (NMDA) receptor known for its neuroprotective effect against excitotoxicity. Our investigation centers on the efficacy of Memantine in mitigating chronic alcohol-induced cognitive and hippocampal damages in vivo. Male C57BL/6J mice were subjected to 30 % (v/v, 6.0 g/kg) ethanol via intragastric administration alongside Memantine co-treatment (10 mg/kg/day, intraperitoneally) for six weeks. The assessment involved Y maze, Morris water maze, and novel object recognition tests to evaluate spatial and recognition memory deficits. Histopathological evaluations of the hippocampus were conducted to examine the extent of alcohol-induced morphological changes and the potential protective effect of Memantine. The findings reveal that Memantine significantly improves chronic alcohol-compromised cognitive functions and mitigates hippocampal pathological changes, implicating a moderating effect on the disassembly of actin cytoskeleton and microtubules in the hippocampus, induced by chronic alcohol exposure. Our results underscore Memantine's capability to attenuate chronic alcohol-induced cognitive and hippocampal morphological harm may partly through regulating cytoskeleton dynamics, offering valuable insights into innovative therapeutic strategies for ARCI.

Neuropathology of deaths due to acute alcohol toxicity in Australia, 2011-2022

BACKGROUND

A major alcohol-related harm is structural pathology affecting the brain. The study aimed to: 1. Determine the frequency and nature of neuropathology amongst cases of death due to acute alcohol toxicity; 2. Compare diagnoses of brain atrophy with pathology in other organs; 3. Determine the demographic, clinical and organ pathology correlates of brain atrophy.

METHODS

Retrospective study of 500 cases of death attributed to acute alcohol toxicity in Australia, 2011-2022. Data on clinical characteristics, toxicology, neuropathology and other organ pathology were retrieved from police reports, autopsies, toxicology and coronial findings.

RESULTS

Mean age was 49.5 years, 69.4 % were male, with alcohol use problems documented in 70.2 %. Brain atrophy was diagnosed in 60 cases (12.0 %), most commonly in the cerebellum (32 cases, 6.4 %). Atrophy at other sites was present in 37 (7.4 %). The presence of brain atrophy was lower than other major pathologies: cardiomegaly (32.6 %, p<.001), nephro/arteriosclerosis (30.2 %, p<.001), and chronic obstructive pulmonary disease (21.8 %, p<.001) but not hepatic cirrhosis (11.9 % p=1.0). Those diagnosed with atrophy were older (53.4v 49.0 years, p<.001), more likely to have documented alcohol problems (85.0v 68.2 %, Odds ratio: OR 2.53) and seizure history (10.0v 3.0 %, OR 2.92), to have cardiomegaly (43.3v 31.0 %, OR 1.90, COPD (48.3v 18.2 %, 3.57) and nephro/arteriosclerosis (50.0 v 27.4 %, OR 2.27).

CONCLUSIONS

Despite the majority of cases having a history of alcohol problems, the level of neuropathology amongst cases of death due to acute alcohol toxicity was comparatively low.

Differential regulation of G protein-coupled receptor-associated proteins in the caudate and the putamen of cynomolgus macaques following chronic ethanol drinking

The dorsal striatum is composed of the caudate nucleus and the putamen in human and non-human primates. These two regions receive different cortical projections and are functionally distinct. The caudate is involved in the control of goal-directed behaviors, while the putamen is implicated in habit learning and formation. Previous reports indicate that ethanol differentially influences neurotransmission in these two regions. Because neurotransmitters primarily signal through G protein-coupled receptors (GPCRs) to modulate neuronal activity, the present study aimed to determine whether ethanol had a region-dependent impact on the expression of proteins that are involved in the trafficking and function of GPCRs, including G protein subunits and their effectors, protein kinases, and elements of the cytoskeleton. Western blotting was performed to examine protein levels in the caudate and the putamen of male cynomolgus macaques that self-administered ethanol for 1 year under free access conditions, along with control animals that self-administered an isocaloric sweetened solution under identical operant conditions. Among the 18 proteins studied, we found that the levels of one protein (PKCβ) were increased, and 13 proteins (Gαi1/3, Gαi2, Gαo, Gβ1γ, PKCα, PKCε, CaMKII, GSK3β, β-actin, cofilin, α-tubulin, and tubulin polymerization promoting protein) were reduced in the caudate of alcohol-drinking macaques. However, ethanol did not alter the expression of any proteins examined in the putamen. These observations underscore the unique vulnerability of the caudate nucleus to changes in protein expression induced by chronic ethanol exposure. Whether these alterations are associated with ethanol-induced dysregulation of GPCR function and neurotransmission warrants future investigation.

The Association between Individual Food Groups, Limbic System White Matter Tracts, and Episodic Memory: Initial Data from the Aiginition Longitudinal Biomarker Investigation of Neurodegeneration (ALBION) Study

(1) Background: Many studies link food intake with clinical cognitive outcomes, but evidence for brain biomarkers, such as memory-related limbic white matter (WM) tracts, is limited. We examined the association between food groups, limbic WM tracts integrity, and memory performance in community-dwelling individuals. (2) Methods: We included 117 non-demented individuals (ALBION study). Verbal and visual episodic memory tests were administered, and a composite z-score was calculated. Diffusion tensor imaging tractography was applied for limbic WM tracts (fornix-FX, cingulum bundle-CB, uncinate fasciculus-UF, hippocampal perforant pathway zone-hPPZ). Food intake was evaluated through four 24-h recalls. We applied linear regression models adjusted for demographics and energy intake. (3) Results: We found significant associations between (a) higher low-to-moderate alcohol intake and higher FX fractional anisotropy (FA), (b) higher full-fat dairy intake and lower hPPZ FA, and (c) higher red meat and cold cuts intake and lower hPPZ FA. None of the food groups was associated with memory performance. (4) Conclusions: Despite non-significant associations between food groups and memory, possibly due to participants' cognitive profile and/or compensatory mechanisms, the study documented a possible beneficial role of low-to-moderate alcohol and a harmful role of full-fat dairy and red meat and cold cuts on limbic WM tracts.

Alcohol consumers with liver pathology rarely display α-synuclein pathology

It has been suggested that alcohol consumption protects against Parkinson's disease (PD). Here we assessed postmortem tissue samples from the brains and livers of 100 subjects with ages at death ranging from 51 to 93. Twenty percent of these subjects were demented. We used standardized assessment strategies to assess both the brain and liver pathologies (LP). Our cohort included subjects with none, mild, moderate, and severe LP caused by alcohol consumption. We noted a significant negative correlation of categorical data between liver steatosis and α-synuclein (αS) in the brain and a significant negative correlation between the extent of liver steatosis and fibrosis and the extent of αS in the brain. There was a significant negative association between the observation of Alzheimer's type II astrocytes and αS pathology in the brain. No association was noted between LP and hyperphosphorylated τ (HPτ). No significant correlation could be seen between the extent of LP and the extent of HPτ, amyloid β protein (Aβ) or transactive DNA binding protein 43 (TDP43) in the brain. There were significant correlations observed between the extent of HPτ, Aβ, αS, and TDP43 in the brain and between liver steatosis, inflammation, and fibrosis. Subjects with severe LP displayed a higher frequency of Alzheimer's type II astrocytes compared to those with no, or mild, LP. The assessed protein alterations were not more prevalent or severe in subjects with Alzheimer's type II astrocytes in the brain. In all cases, dementia was attributed to a combination of altered proteins, i.e., mixed dementia and dementia was observed in 30% of those with mild LP when compared with 13% of those with severe LP. In summary, our results are in line with the outcome obtained by the two recent meta-analyses suggesting that subjects with a history of alcohol consumption seldom develop an α-synucleinopathy.

Cognitive impairment in patients awaiting kidney and liver transplantation-A clinically relevant problem?

INTRODUCTION

Cognitive impairment (CI) is common in both end-stage kidney disease (ESKD) and alcohol-related liver cirrhosis. The aim of this study was to assess the prevalence and patterns of CI in patients awaiting kidney and liver transplantation, and to identify its determinants.

METHODS

In this cross-sectional, prospective study, 31 consecutive patients with ESKD and 31 consecutive patients with alcohol-related liver cirrhosis, all currently on transplant waiting lists, were screened for cognitive decline using the Addenbrooke's Cognitive Examination. Medical history, demographics, and laboratory test results were also collected.

RESULTS

The prevalence of CI among patients with ESKD and alcohol-related liver cirrhosis was 26% and 90%, respectively. In both groups, memory was the most affected cognitive domain, along with verbal fluency in patients with ESKD, and visuospatial abilities in patients with alcoholic cirrhosis. The most statistically significant increase in the prevalence of CI was found in patients with lower educational attainment, in both alcohol-related liver cirrhosis and ESKD populations as well as in older patients with alcoholic cirrhosis. Furthermore, better cognitive functioning in ESKD patients was associated with higher levels of total lymphocyte count and alanine transaminase (ALT), and in alcohol-related liver cirrhosis patients with higher levels of ALT and aspartate transaminase. A nonsignificant trend toward lower memory domain scores was also observed with increasing ammonia levels and increasing severity of liver disease (higher Child-Pugh scores). Finally, suboptimal performance on the screening test was correlated with the severity of liver disease as assessed by the Model for End-Stage Liver Disease Sodium (MELD-Na), but not at the statistically significant level.

CONCLUSIONS

The prevalence of CI, especially in patients with alcohol-related liver cirrhosis, is high and can be a significant clinical problem, negatively affecting the transplantation process. Routine screening tests in this group would contribute to the implementation of appropriate management, such as rehabilitation program or psychosocial treatments and facilitate the provision of specialized health care.

Cognitive deficits persisting in patients with alcohol dependence syndrome after detoxification

Background

Alcohol-related cognitive deficits (ARCDs) have received little clinical recognition due to doubts regarding the etiopathogenesis and lack of consensus in the diagnostic guidelines.

Aim

The present study aimed at evaluating the pattern of cognitive deficits in patients of alcohol dependence without dementia, and assessing the relationship between these subtle cognitive deficits and alcohol use parameters.

Materials and Methods

The study included randomly selected, consenting, non-delirious patients of alcohol dependence syndrome (ADS) without dementia, admitted in the de-addiction ward. Cognition was assessed by Mini Mental State Examination (MMSE) of the Diagnostic Interview for Genetic Studies at admission and after 7 days of detoxification. "T-test" was used to assess cognitive improvement and residual deficits, while correlation analysis was used to compare the relationship between alcohol use parameters and MMSE scores.

Results

We recruited 63 male patients with mean age of 38.62 (±9.61) years. Significant improvement was noted in cognition post-detoxification. However, most of the subjects had subtle cognitive deficits which may fall within the realm of ARCD, mainly in domains of attention/concentration, recall, language, and visuo-constructional skills (P < 0.05). The cognitive deficits correlated with duration and severity of alcohol dependence (P < 0.05), however, were independent of daily alcohol quantity.

Conclusion

Subtle cognitive deficits may persist in patients of ADS without dementia, even after successful detoxification. They may be easily missed despite contact with mental health professionals, as these deficits may only be evident on neuro-psychological testing.

Abstinence as Choice: Exploring Voluntary Abstinence from Alcohol Self-Administration Using the Resurgence-as-Choice Framework

Resurgence is an increase in the rate of a previously suppressed behavior that occurs when an alternative source of reinforcement is made worse in some way. The Resurgence as Choice model offers a quantitative approach to understanding resurgence that may provide important insights into the variables that affect this form of relapse in the natural environment. Bringing this model to bear on relapse following reinforcement-based interventions for alcohol and other substance use disorders, however, may not be straightforward. Laboratory work on which the Resurgence as Choice model is based has almost exclusively focused on resurgence following extinction of target behavior, but abstinence from alcohol during intervention is often voluntary: Patients may drink alcohol and forfeit therapeutic reinforcers at any time. In this article, we first will review recent data from our group that demonstrate a method for studying resurgence following voluntary abstinence from alcohol seeking in rats. In a previous experiment, we reduced rats' alcohol-maintained lever pressing to low levels without placing it on extinction by arranging nondrug differential reinforcement of other behavior. Further, when we suspended nondrug reinforcement, resurgence of lever pressing occurred. Next, we will explore methods for modeling these outcomes using the Resurgence-as-Choice framework. We conclude that the data under consideration may not be sufficient to discriminate between candidate models of resurgence following voluntary abstinence and point to areas for future empirical and theoretical development. This work may provide a stronger bridge between preclinical and conceptual work on resurgence and clinical treatments for alcohol use disorder.

Alcohol Use Disorder and Dementia: A Review

PURPOSE

By 2040, 21.6% of Americans will be over age 65, and the population of those older than age 85 is estimated to reach 14.4 million. Although not causative, older age is a risk factor for dementia: every 5 years beyond age 65, the risk doubles; approximately one-third of those older than age 85 are diagnosed with dementia. As current alcohol consumption among older adults is significantly higher compared to previous generations, a pressing question is whether drinking alcohol increases the risk for Alzheimer's disease or other forms of dementia.

SEARCH METHODS

Databases explored included PubMed, Web of Science, and ScienceDirect. To accomplish this narrative review on the effects of alcohol consumption on dementia risk, the literature covered included clinical diagnoses, epidemiology, neuropsychology, postmortem pathology, neuroimaging and other biomarkers, and translational studies. Searches conducted between January 12 and August 1, 2023, included the following terms and combinations: "aging," "alcoholism," "alcohol use disorder (AUD)," "brain," "CNS," "dementia," "Wernicke," "Korsakoff," "Alzheimer," "vascular," "frontotemporal," "Lewy body," "clinical," "diagnosis," "epidemiology," "pathology," "autopsy," "postmortem," "histology," "cognitive," "motor," "neuropsychological," "magnetic resonance," "imaging," "PET," "ligand," "degeneration," "atrophy," "translational," "rodent," "rat," "mouse," "model," "amyloid," "neurofibrillary tangles," "α-synuclein," or "presenilin." When relevant, "species" (i.e., "humans" or "other animals") was selected as an additional filter. Review articles were avoided when possible.

SEARCH RESULTS

The two terms "alcoholism" and "aging" retrieved about 1,350 papers; adding phrases-for example, "postmortem" or "magnetic resonance"-limited the number to fewer than 100 papers. Using the traditional term, "alcoholism" with "dementia" resulted in 876 citations, but using the currently accepted term "alcohol use disorder (AUD)" with "dementia" produced only 87 papers. Similarly, whereas the terms "Alzheimer's" and "alcoholism" yielded 318 results, "Alzheimer's" and "alcohol use disorder (AUD)" returned only 40 citations. As pertinent postmortem pathology papers were published in the 1950s and recent animal models of Alzheimer's disease were created in the early 2000s, articles referenced span the years 1957 to 2024. In total, more than 5,000 articles were considered; about 400 are herein referenced.

DISCUSSION AND CONCLUSIONS

Chronic alcohol misuse accelerates brain aging and contributes to cognitive impairments, including those in the mnemonic domain. The consensus among studies from multiple disciplines, however, is that alcohol misuse can increase the risk for dementia, but not necessarily Alzheimer's disease. Key issues to consider include the reversibility of brain damage following abstinence from chronic alcohol misuse compared to the degenerative and progressive course of Alzheimer's disease, and the characteristic presence of protein inclusions in the brains of people with Alzheimer's disease, which are absent in the brains of those with AUD.

Adolescent binge ethanol impacts H3K9me3-occupancy at synaptic genes and the regulation of oligodendrocyte development

Introduction

Binge drinking in adolescence can disrupt myelination and cause brain structural changes that persist into adulthood. Alcohol consumption at a younger age increases the susceptibility of these changes. Animal models to understand ethanol's actions on myelin and white matter show that adolescent binge ethanol can alter the developmental trajectory of oligodendrocytes, myelin structure, and myelin fiber density. Oligodendrocyte differentiation is epigenetically regulated by H3K9 trimethylation (H3K9me3). Prior studies have shown that adolescent binge ethanol dysregulates H3K9 methylation and decreases H3K9-related gene expression in the PFC.

Methods

Here, we assessed ethanol-induced changes to H3K9me3 occupancy at genomic loci in the developing adolescent PFC. We further assessed ethanol-induced changes at the transcription level with qPCR time course approaches in oligodendrocyte-enriched cells to assess changes in oligodendrocyte progenitor and oligodendrocytes specifically.

Results

Adolescent binge ethanol altered H3K9me3 regulation of synaptic-related genes and genes specific for glutamate and potassium channels in a sex-specific manner. In PFC tissue, we found an early change in gene expression in transcription factors associated with oligodendrocyte differentiation that may lead to the later significant decrease in myelin-related gene expression. This effect appeared stronger in males.

Conclusion

Further exploration in oligodendrocyte cell enrichment time course and dose response studies could suggest lasting dysregulation of oligodendrocyte maturation at the transcriptional level. Overall, these studies suggest that binge ethanol may impede oligodendrocyte differentiation required for ongoing myelin development in the PFC by altering H3K9me3 occupancy at synaptic-related genes. We identify potential genes that may be contributing to adolescent binge ethanol-related myelin loss.

Excessive intragastric alcohol administration exacerbates hepatic encephalopathy and provokes neuronal cell death in male rats with chronic liver disease

Hepatic encephalopathy (HE) is defined as decline in neurological function during chronic liver disease (CLD). Alcohol is a major etiological factor in the pathogenesis of fibrosis/cirrhosis and has also been documented to directly impact the brain. However, the role of alcohol in the development of HE in CLD remains unclear. Here, we investigated the impact of excessive alcohol administration on neurological deterioration in rats with CLD. Starting day 7 post-BDL surgery, rats were administered alcohol twice daily (51% v/v ethanol, 3 g/kg, via gavage) for 4 weeks. Motor coordination was assessed weekly using rotarod and anxiety-like behavior was evaluated with open field and elevated plus maze at 5 weeks. Upon sacrifice, brains were collected for western blot and immunohistochemical analyses to investigate neuronal integrity and oxidative stress status. Alcohol worsened motor coordination performance and increased anxiety-like behavior in BDL rats. Impairments were associated with decreased neuronal markers of NeuN and SMI311, increased apoptotic markers of cleaved/pro-caspase-3 and Bax/Bcl2, increased necroptosis markers of pRIP3 and pMLKL, decreased total antioxidant capacity (TAC), and increased 4-hydroxynonenal (4-HNE)modified proteins in the cerebellum of BDL-alcohol rats when compared to respective controls. Immunofluorescence confirmed the colocalization of cleaved caspase-3 and pMLKL in the granular neurons of the cerebellum of BDL-alcohol rats. Excessive alcohol consumption exacerbates HE which leads to associated apoptotic and necroptotic neuronal loss in the cerebellum of BDL-alcohol rats. Additionally, higher levels of 4-HNE and decreased TAC in the cerebellum of BDL-alcohol rats suggest oxidative stress is the triggering factor of apoptotic and necroptotic neuronal loss/injury.

Changes of neurofilament light chain in patients with alcohol dependence following withdrawal and the genetic effect from ALDH2 Polymorphism

Neurofilament light chain (NFL), as a measure of neuroaxonal injury, has recently gained attention in alcohol dependence (AD). Aldehyde dehydrogenase 2 (ALDH2) is the major enzyme which metabolizes the alcohol breakdown product acetaldehyde. An ALDH2 single nucleotide polymorphism (rs671) is associated with less ALDH2 enzyme activity and increased neurotoxicity. We examined the blood NFL levels in 147 patients with AD and 114 healthy controls using enzyme-linked immunosorbent assay and genotyped rs671. We also followed NFL level, alcohol craving and psychological symptoms in patients with AD after 1 and 2 weeks of detoxification. We found the baseline NFL level was significantly higher in patients with AD than in controls (mean  ±  SD: 264.2  ±  261.8 vs. 72.1 ± 35.6 pg/mL, p < 0.001). The receiver operating characteristic curve revealed that NFL concentration could discriminate patients with AD from controls (area under the curve: 0.85; p < 0.001). The NFL levels were significantly reduced following 1 and 2 weeks of detoxification, with the extent of reduction correlated with the improvement of craving, depression, and anxiety (p < 0.001). Carriers with the rs671 GA genotype, which is associated with less ALDH2 activity, had higher NLF levels either at baseline or after detoxification compared with GG carriers. In conclusion, plasma NFL level was increased in patients with AD and reduced after early abstinence. Reduction in NFL level corroborated well with the improvement of clinical symptoms. The ALDH2 rs671 polymorphism may play a role in modulating the extent of neuroaxonal injury and its recovery.

Patterns of Alcohol Use in Hispanic Individuals with TBI over the Ten Years Post-Injury: A Model Systems Study

The study's aim was to examine alcohol consumption patterns and predictors of consumption across time among Hispanics with traumatic brain injury (TBI) in the U.S. within ten years post-injury. This longitudinal cohort study included 1342 Hispanic individuals (77.6% males) from the multi-site, longitudinal TBI Model Systems (TBIMS) database. The main outcome measures were consumption information, demographic, and injury characteristics. Across the full sample, alcohol consumption variables generally demonstrated quadratic movement characterized by an initial increase followed by a plateau or slight decrease over the ten years post-injury. The predictors of higher consumption were being men, single, with a history of excessive alcohol use, with a nonviolent mechanism of injury, shorter duration of PTA, and higher levels of education. Participants had a greater number of 5+ drinks/episode occurrences in the past month if they were men and had had a greater number of 5+ drinks/episode occurrences in the month before injury. There was no differential change in alcohol consumption over time as a function of these predictors. This study identified a profile of at-risk Hispanics with TBI for increased alcohol consumption. These individuals should be identified and targeted for early evidence-based alcohol intervention after TBI when results might be most favorable.

Alcohol-related cognitive impairments in patients with and without cirrhosis

AIMS

up to 80% of patients with alcohol use disorder display cognitive impairments. Some studies have suggested that alcohol-related cognitive impairments could be worsened by hepatic damage. The primary objective of this study was to compare mean scores on the Brief Evaluation of Alcohol-Related Neurocognitive Impairments measure between alcohol use disorder patients with (CIR+) or without cirrhosis (CIR-).

METHODS

we conducted a prospective case-control study in a hepatology department of a university hospital. All patients were assessed using the Evaluation of Alcohol-Related Neuropsychological Impairments test.

RESULTS

a total of 82 patients (50 CIR+, 32 CIR-) were included in this study. CIR- patients were significantly younger than CIR+ patients (respectively, 45.5 ± 6.8 vs 60.1 ± 9.0; P < .0001). After adjusting for age and educational level, the mean Evaluation of Alcohol-Related Neuropsychological Impairments total scores in the CIR+ group were significantly lower than in the group of CIR- patients (14.1 ± 0.7 vs 7.8 ± 0.4, respectively, P < .0001). The mean subscores on delayed verbal memory, alphabetical ordination, alternating verbal fluency, visuospatial abilities, and ataxia subtests were also significantly lower in the CIR+ than in the CIR- group (respectively, 1.9 ± 0.2 vs 2.8 ± 0.2; 1.8 ± 0.2 vs 2.7 ± 0.2; 2.2 ± 0.2 vs 3.6 ± 0.2; 0.7 ± 0.2 vs 1.6 ± 0.2; 0.7 ± 0.2 vs 3.1 ± 0.2; P < .0001 for all comparisons).

CONCLUSIONS

in the present study, alcohol use disorder patients with cirrhosis presented more severe cognitive impairments than those without cirrhosis. Longitudinal studies are needed to investigate how cirrhosis can influence cognitive impairments.

Alcohol-related dementia

Dementia is one of the leading causes of death both in the UK and worldwide. Approximately 1 million people have been diagnosed with this condition in the UK. Although there are many types of dementia, this article will focus on alcohol-related dementia. Alcohol has become a leading cause of death in the 50-69-year age group in England, and with consumption rising rapidly, there is an increased risk that young and middle-aged people will develop alcohol-related dementia in the future. The aim of this article is to review the evidence base and discuss whether alcohol-related dementia is a sub-class of dementia or a separate entity.

Alcohol degradation, learning, and memory-enhancing effect of Acetobacter pasteurianus BP2201 in Caenorhabditis elegans model

AIMS

This study aimed to investigate the probiotic effects of Acetobacter pasteurianus BP2201, isolated from brewing mass, for the treatment of alcohol-induced learning and memory ability impairments in a Caenorhabditis elegans model.

METHODS AND RESULTS

Acetobacter pasteurianus BP2201 was examined for probiotic properties, including acid and bile salt resistance, ethanol degradation, antioxidant efficacy, hemolytic activity, and susceptibility to antibiotics. The strain displayed robust acid and bile salt tolerance, efficient ethanol degradation, potent antioxidant activity, and susceptibility to specific antibiotics. Additionally, in the C. elegans model, administering A. pasteurianus BP2201 significantly improved alcohol-induced learning and memory impairments.

CONCLUSIONS

Acetobacter pasteurianus BP2201 proves to be a promising candidate strain for the treatment of learning and memory impairments induced by alcohol intake.

D-ribose-L-cysteine exhibits neuroprotective activity through inhibition of oxido-behavioral dysfunctions and modulated activities of neurotransmitters in the cerebellum of Juvenile mice exposed to ethanol

Alcohol exposure to the cerebellum has been known to trigger cerebellar dysfunctions through several mechanisms. This present study was designed to evaluate the repealing effect of D-ribose-L-cysteine (DRLC) on alcohol-induced cerebellar dysfunctions in juvenile BALB/c mice. The animals were randomly divided into 4 groups (n = 10 per group). Mice were given oral administration of normal saline (control), DRLC (100 mg/kg, p.o), ethanol (0.2 mL of 10% w/v), or DRLC (100 mg/kg, p.o) + ethanol (0.2 mL of 10% w/v). On day 29 of the study (i.e., 24 h after the administration of the last respective doses), neurochemical quantification of the respective levels of serotonin and dopamine, lipid peroxidation, total antioxidant, superoxide dismutase, and glutathione peroxidase in the cerebellar tissues of the mice were analyzed. Compared with the saline-treated group, the studied neurochemical indices were modulated across the various experimental groups. The administration of ethanol significantly modulates the levels of monoamine neurotransmitters (serotonin and dopamine) as well as contents of total antioxidants, activities of superoxide dismutase, and glutathione peroxidase, with a concurrently increased level of lipid peroxidase in the cerebellar tissue of the mice. DRLC significantly reverses these effects in the DRLC + ethanol co-treated group. Combined exposure to DRLC + ethanol counteracts the deleterious effect of ethanol in the cerebellum of juvenile BALB/c mice via monoamine neurotransmitter, lipid peroxidation, total antioxidant status, superoxide dismutase, and glutathione peroxidase action pathways. Therefore, DRLC could be a pharmacologic or therapeutic agent in attenuating the deleterious effects of alcohol on the cerebellum.

Over a Century of Study and Still Misunderstood: Recognizing the Spectrum of Acute and Chronic Wernicke-Korsakoff Syndrome

The aim of this study was to objectively evaluate the hypothesis that the neuropsychological presentation of Korsakoff's syndrome, the chronic phase of Wernicke-Korsakoff syndrome (WKS), is invariably a severe, selective amnesia against a background of relatively preserved general intellectual functions in a consecutive clinical sample. An analysis of the neuropsychological profiles of nine cases with a recorded history of WKS was undertaken. All cases were adult males (ages 32 to 70) with a long history of alcohol use disorder. Eight cases were chosen retrospectively on a consecutive basis from patient referrals. One additional case was recruited prospectively. Conventional understanding and some current opinion of Korsakoff's syndrome predicts anterograde memory to be consistently more impaired than other cognitive abilities, but this was not found in this case series. The Mean Wechsler Delayed Memory Index was not significantly different from the Wechsler Full-Scale IQ (FSIQ), p = 0.130. Regression of Delayed Memory on FSIQ produced a non-significant intercept, p = 0.213. The 'hallmark' criterion of anterograde memory score at least 20 points less than intelligence score was observed in four of eight cases with available data, equating to a 'sensitivity' of 50%. Three of eight cases with available data had an FSIQ less than the memory score. Contrary to a common view, general intellectual function was not consistently preserved in Korsakoff's syndrome relative to memory function. This study illustrates one of the specific merits of case series, namely, to critique an established view. Clinicians and researchers should expand their diagnostic criteria for Korsakoff's syndrome to include more variable cognitive phenotypes, including a potentially reversible dementia-like impairment of variable severity, and focus on potential treatment opportunities.

Brain proteomic atlas of alcohol use disorder in adult males

Alcohol use disorder (AUD) affects transcriptomic, epigenetic and proteomic expression in several organs, including the brain. There has not been a comprehensive analysis of altered protein abundance focusing on the multiple brain regions that undergo neuroadaptations occurring in AUD. We performed a quantitative proteomic analysis using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of human postmortem tissue from brain regions that play key roles in the development and maintenance of AUD, the amygdala (AMG), hippocampus (HIPP), hypothalamus (HYP), nucleus accumbens (NAc), prefrontal cortex (PFC) and ventral tegmental area (VTA). Brain tissues were from adult males with AUD (n = 11) and matched controls (n = 16). Across the two groups, there were >6000 proteins quantified with differential protein abundance in AUD compared to controls in each of the six brain regions. The region with the greatest number of differentially expressed proteins was the AMG, followed by the HYP. Pathways associated with differentially expressed proteins between groups (fold change > 1.5 and LIMMA p < 0.01) were analyzed by Ingenuity Pathway Analysis (IPA). In the AMG, adrenergic, opioid, oxytocin, GABA receptor and cytokine pathways were among the most enriched. In the HYP, dopaminergic signaling pathways were the most enriched. Proteins with differential abundance in AUD highlight potential therapeutic targets such as oxytocin, CSNK1D (PF-670462), GABAB receptor and opioid receptors and may lead to the identification of other potential targets. These results improve our understanding of the molecular alterations of AUD across brain regions that are associated with the development and maintenance of AUD. Proteomic data from this study is publicly available at www.lmdomics.org/AUDBrainProteomeAtlas/ .

Observations on the Clinical Features of the Wernicke-Korsakoff Syndrome

This paper begins with a short case report of florid, spontaneous confabulation in a 61-year-old man with an alcohol-induced Wernicke-Korsakoff syndrome. His confabulation extended across episodic and personal semantic memory, as well as orientation in time and place, as measured on Dalla Barba's Confabulation Battery. Five other brief case summaries will then be presented, followed by a summary of the clinical, neurological, and background neuropsychological findings in three earlier series of Korsakoff patients. These observations will be considered in light of Wijnia's recent and my own, earlier reviews of the Korsakoff syndrome. Taken together, they indicate the need for a multi-faceted approach (clinical, neurological, neuropsychological, and neuroimaging) to the assessment and diagnosis of the disorder.

Neurocognitive Recovery in Abstinent Patients with Alcohol Use Disorder: A Scoping Review for Associated Factors

Objective

Studies have reported inconsistent results regarding the extent to which neurocognitive recovery occurs in abstinent patients with alcohol use disorder (AUD). In addition to abstinence, other factors may have influenced this process and contributed to the inconsistencies. This review examines the factors investigated in this regard and describes the possible influence of each factor based on the evidence collected.

Methodology

PubMed was systematically searched for articles published between January 2000 and July 2023. Longitudinal humane studies investigating neurocognitive recovery in abstinent adult AUD patients were included. Studies with a cross-sectional design were excluded, as were studies that did not classify AUD according to the DSM-IV or 5 criteria, only examined binge use, did not report neuropsychological outcomes or duration of abstinence, or where neurological disorders were present.

Results

Sixteen categories of factors were distinguished from 31 full-text articles. Consistent patterns were found, indicating an association between neurocognitive recovery and the "smoking" and 'brain volume" factors. Consistent patterns were also found indicating that there is no relationship with "quantities of alcohol used" and "education level." A similar consistent pattern was also found for "polysubstance use", "gender" and "verbal reading", but the number of studies is considered limited. The association with "age" is studied frequently but with inconsistent findings. The remaining eight factors were regarded as understudied.

Conclusion

The clearest patterns emerging from the evidence are a predominantly negative influence of smoking on neurocognitive recovery, associations between changes in brain area volume and neurocognitive recovery, and no association between neurocognitive recovery and the amount of alcohol consumed, as measured by self-report, nor with educational attainment. Future research on the understudied factors and factors with inconsistent evidence is needed, preferably through longitudinal designs with multiple assessment periods starting after at least two weeks of abstinence.

Neurotoxicology of alcohol: a bibliometric and science mapping analysis

Alcohol consumption is common in many societies and has increased considerably, resulting in many socioeconomic and public health problems. In this sense, studies have been carried out in order to understand the mechanisms involved in alcohol consumption and related harmful effects. This study aimed to identify and map the knowledge and to perform bibliometric analysis of the neurotoxicology of alcohol based on the 100 most cited articles. A search was carried out in the Web of Science Core Collection database and information was extracted regarding the journal, authors, keywords, year of publication, number of citations, country and continent of the corresponding author. For each selected manuscript, the study design, alcohol exposure model, dose, period of exposure, and effect on the central nervous system and research hotspots were mapped. The journal with the highest number of publications was Alcoholism: Clinical and Experimental Research (n = 11 papers), the author who contributed the most was Crews FT (n = 8 papers), the studies had a total of 288 keywords and 75% of the publications were from the United States of America. The experimental studies evaluated the effects of prenatal and postnatal exposure and were conducted in rats and mice using doses ranging from 2.5 to 14 g/kg/day, with administration by subcutaneous, intraperitoneal, intragastric, or inhalation route or with free access through drinking bottles. Among the studies mapped, the oldest one (1989) aimed to understand the systemic damage and mechanisms of action involved, while the most recent focused on understanding the receptors and mechanisms involved in addiction, as well as genetic factors. Our results show the panorama of the most widespread scientific production in the scientific community on the neurotoxicology of ethanol, a high prevalence was observed in studies that addressed fetal alcohol syndrome and/or the effects of ethanol on neurodevelopment.

Frontal Hypoperfusion and Cerebellar Hyperperfusion in Transient Alcoholic Cerebellar Degeneration

ABSTRACT

A 55-year-old man consumed approximately 10 units of alcohol daily for 25 years, developing social withdrawal after retiring. For 2 months, he walked diagonally to the right, with a right shoulder droop. He spoke and walked slowly, but his speech was clear. After 20 days of abstinence, his symptoms improved, and his walk became more steady. Brain MRI revealed no specific finding. Brain perfusion scintigraphy with 99m Tc-ECD on 2-tailed view display in eZIS showed hypoperfusion in the prefrontal, frontal, and left anterior temporal lobes and left thalamus and hyperperfusion in the posterior white matter, parietal-occipital cortical regions, pons, and cerebellum.

Alcohol and the central nervous system

Ethanol use is common to most cultures but with varying doses and to varying extents. While research has focused on the effects on the liver, alcohol exerts a range of actions on the function and structure of the nervous system. In the central nervous system (CNS) it can provoke or exacerbate neurological and psychiatric disease; its effects on the peripheral nervous system are not included in this review. Sustained alcohol intake can predispose to acute neurochemical changes which, with continued ingestion and incomplete treatment, can lead to chronic structural changes in the CNS: these include generalised cortical and cerebellar atrophy, amnesic syndromes such as Korsakoff's syndrome, and specific white matter disorders such as central pontine myelinolysis and Marchiafava-Bignami syndrome. Alcohol in pregnancy commonly and significantly affects fetal health, though this receives less medical and political attention than other causes of fetal harm. This review looks at the range of disorders that can follow acute or chronic alcohol use, and how these should be managed, and we provide a practical overview on how neurologists might diagnose and manage alcohol addiction.

Gender inequalities as contributors to dementia in Latin America and the Caribbean: what factors are missing from research?

The current knowledge of modifiable risk factors for dementia comes mainly from high-income countries. In Latin America and Caribbean countries, where the burden of gender and socioeconomic inequalities is greater than in high-income countries, the prevalence of dementia is also higher and disease onset is earlier, especially among women, even after adjustments for life expectancy. In this Personal View, we discuss socioeconomic modifiable risk factors for dementia established by previous studies and postulate further harmful and often hidden factors faced by women that might influence the gender-specific timing of onset and general prevalence of dementia. We emphasise some of the effects of gender roles, their direct and indirect effects on dementia, and how they disproportionately impact women. Finally, we highlight the importance of bringing hidden risk factors to open discussion to promote research with high-quality data and to encourage public policies to promote and preserve women's health.

Effects of chronic and binge ethanol administration on mouse cerebellar and hippocampal neuroinflammation

Background: Hippocampal and cerebellar neuropathology occurs in individuals with alcohol use disorders (AUD), resulting in impaired cognitive and motor function.Objectives: Evaluate the effects of ethanol on the expression of pro- and anti-inflammatory molecules, as well as the effects of the anti-inflammatory PPAR-γ agonist pioglitazone in suppressing ethanol-induced neuroinflammation.Methods: Adult male and female mice were treated chronically with ethanol for just under a month followed by a single acute binge dose of ethanol. Animals were provided liquid diet in the absence of ethanol (Control; n = 18, 9 M/9F), liquid diet containing ethanol (ethanol; n = 22, 11 M/11F), or liquid diet containing ethanol plus gavage administration of 30.0 mg/kg pioglitazone (ethanol + pioglitazone; n = 20, 10 M/10F). The hippocampus and cerebellum were isolated 24 h following the binge dose of ethanol, mRNA was isolated, and pro- and anti-inflammatory molecules were quantified by qRT-PCR.Results: Ethanol significantly (p < .05) increased the expression of pro-inflammatory molecules IL-1β, TNF-α, CCL2, and COX2; increased the expression of inflammasome-related molecules NLRP3 and Casp1 but decreased IL-18; and altered the expression of anti-inflammatory molecules including TGFβR1 in the hippocampus and cerebellum, though some differences were observed between males and females and the two brain regions. The anti-inflammatory pioglitazone inhibited ethanol-induced alterations in the expression of most, but not all, inflammation-related molecules.Conclusion: Chronic plus binge administration of ethanol induced the expression of inflammatory molecules in adult mice and pioglitazone suppressed ethanol-induced neuroinflammation.

Animal models for studies of alcohol effects on the trajectory of age-related cognitive decline

There is growing interest in understanding how ethanol use interacts with advancing age to influence the brain and cognition. Animal models are employed to investigate the cellular and molecular mechanisms of brain aging and age-related neurodegenerative diseases that underlie cognitive decline. However, all too often research on problems and diseases of the elderly are conducted in healthy young animals, providing little clinical relevance. The validity of animal models is discussed, and confounds due to age-related differences in anxiety, sensory-motor function, and procedural learning are highlighted in order to enhance the successful translation of preclinical results into clinical settings. The mechanism of action of ethanol on brain aging will depend on the dose, acute or chronic treatment, or withdrawal from treatment and the age examined. Due to the fact that humans experience alcohol use throughout life, important questions concern the effects of the dose and duration of ethanol treatment on the trajectory of cognitive function. Central to this research will be questions of the specificity of alcohol effects on cognitive functions and related brain regions that decline with age, as well as the interaction of alcohol with mechanisms or biomarkers of brain aging. Alternatively, moderate alcohol use may provide a source of reserve and resilience against brain aging. Longitudinal studies have the advantage of being sensitive to detecting the effects of treatment on the emergence of cognitive impairment in middle age and can minimize effects of stress/anxiety associated with the novelty of alcohol exposure and behavioral testing, which disproportionately influence aged animals. Finally, the effect of alcohol on senescent neurophysiology and biomarkers of brain aging are discussed. In particular, the interaction of age and effects of alcohol on inflammation, oxidative stress, N-methyl-d-aspartate receptor function, and the balance of excitatory and inhibitory synaptic transmission are highlighted.

Cerebellar Transcriptomic Analysis in a Chronic plus Binge Mouse Model of Alcohol Use Disorder Demonstrates Ethanol-Induced Neuroinflammation and Altered Glial Gene Expression

Alcohol use disorder (AUD) is one of the most common preventable mental health disorders and can result in pathology within the CNS, including the cerebellum. Cerebellar alcohol exposure during adulthood has been associated with disruptions in proper cerebellar function. However, the mechanisms regulating ethanol-induced cerebellar neuropathology are not well understood. High-throughput next generation sequencing was performed to compare control versus ethanol-treated adult C57BL/6J mice in a chronic plus binge model of AUD. Mice were euthanized, cerebella were microdissected, and RNA was isolated and submitted for RNA-sequencing. Down-stream transcriptomic analyses revealed significant changes in gene expression and global biological pathways in control versus ethanol-treated mice that included pathogen-influenced signaling pathways and cellular immune response pathways. Microglial-associated genes showed a decrease in homeostasis-associated transcripts and an increase in transcripts associated with chronic neurodegenerative diseases, while astrocyte-associated genes showed an increase in transcripts associated with acute injury. Oligodendrocyte lineage cell genes showed a decrease in transcripts associated with both immature progenitors as well as myelinating oligodendrocytes. These data provide new insight into the mechanisms by which ethanol induces cerebellar neuropathology and alterations to the immune response in AUD.

Informing the development of diagnostic criteria for differential diagnosis of alcohol-related cognitive impairment (ARCI) among heavy drinkers: A systematic scoping review

BACKGROUND

Early detection and diagnosis of alcohol-related cognitive impairment (ARCI) among heavy drinkers is crucial to facilitating appropriate referral and treatment. However, there is lack of consensus in defining diagnostic criteria for ARCI. Uncertainty in attributing a diagnosis of suspected ARCI commonly arises in clinical practice and opportunities to intervene are missed. A systematic scoping review approach was taken to (i) summarise evidence relating to screening or diagnostic criteria used in clinical studies to detect ARCI; and (ii) to determine the extent of the research available about cognitive assessment tools used in 'point-of-care' screening or assessment of patients with suspected non-Korsakoff Syndrome forms of ARCI.

METHODS

We searched Medline, PsycINFO, Cinahl and the Web of Science, screened reference lists and carried out forward and backwards citation searching to identify clinical studies about screening, diagnosis or assessment of patients with suspected ARCI.

RESULTS

In total, only 7 studies met our primary objective and reported on modifications to existing definitions or diagnostic criteria for ARCI. These studies revealed a lack of coordinated research and progress towards the development and standardisation of diagnostic criteria for ARCI. Cognitive screening tools are commonly used in practice to support a diagnosis of ARCI, and as a secondary objective we included an additional 12 studies, which covered a range of settings and patient populations relevant to screening, diagnosis or assessment in acute, secondary or community 'point-of-care' settings. Across two studies with a defined ARCI patient sample and a further four studies with an alcohol use disorder patient sample, the accuracy, validity and/or reliability of seven different cognitive assessment tools were examined. The remaining seven studies reported descriptive findings, demonstrating the lack of evidence available to draw conclusions about which tools are most appropriate for screening patients with suspected ARCI.

CONCLUSION

This review confirms the scarcity of evidence available on the screening, diagnosis or assessment of patients with suspected ARCI. The lack of evidence is an important barrier to the development of clear guidelines for diagnosing ARCI, which would ultimately improve the real-world management and treatment of patients with ARCI.

Structural brain substrates of the deficits observed on the BEARNI test in alcohol use disorder and Korsakoff's syndrome

Chronic and excessive alcohol consumption can result in alcohol use disorder (AUD) without neurological complications and in Korsakoff's syndrome (KS) when combined with thiamine deficiency. These two clinical forms are accompanied by widespread structural brain damage in both the fronto-cerebellar (FCC) and Papez circuits (PC) as well as in the parietal cortex, resulting in cognitive and motor deficits. BEARNI is a screening tool especially designed to detect neuropsychological impairments in AUD. However, the sensitivity of this tool to the structural brain damage of AUD and KS patients remains unknown. Eighteen KS patients, 47 AUD patients and 27 healthy controls (HC) underwent the BEARNI test and a 3 T-MRI examination. Multiple regression analyses conducted between GM density and performance on each BEARNI subtest revealed correlations with regions included in the FCC, PC, thalamus and posterior cortex (precuneus and calcarine regions). All these brain regions were altered in KS compared to HC, in agreement with the cognitive deficits observed in the corresponding BEARNI subtests. The comparison between KS and AUD regarding the GM density in the several nodes of the FCC and calcarine regions revealed that they were atrophied to the same extent, suggesting that BEARNI is sensitive to the severity of alcohol-related GM abnormalities. Within the PC, the density of the cingulate cortex and thalamus, which correlated with the memory and fluency subscores, was smaller in KS than in AUD, suggesting that BEARNI is sensitive to specific brain abnormalities occurring in KS.

A causal relationship between alcohol intake and type 2 diabetes mellitus: A two-sample Mendelian randomization study

BACKGROUND AND AIMS

We investigated whether alcohol intake has a causal relationship with type 2 diabetes mellitus (T2DM) risk in adults of the Korean Genomic Epidemiology Study using two-sample Mendelian randomization (MR) analysis.

METHODS AND RESULTS

Daily alcohol intake was calculated based on the type, average amount, and frequency of alcohol consumption for six months before the interview. The participants were divided into low- and high-alcohol intake of 20 g/day. After adjusting for the covariates related to T2DM, the independent genetic variants (instrumental variables) related to alcohol intake were explored by GWAS analysis in a city hospital-based cohort (n = 58,701). SNPs with a significant level of p-value <5 × 10^-8 and linkage disequilibrium of r² < 0.001 were retrieved. MR methods were used to analyze the causality between alcohol intake and the T2DM risk, and the heterogeneity and leave-one-out sensitivity analyses were conducted in Ansan/Ansung plus rural cohorts (n = 13,598). High alcohol intake increased T2DM risk when the inverse-variance weighted (P = 0.012) and weighted median (P = 0.034) methods were used, but not when the MR-Egger method was used. No significant heterogeneity and horizontal pleiotropy between alcohol intake and T2DM were detected. A single genetic variant did not affect the causal association in a leave-one-out sensitivity analysis.

CONCLUSION

This study supports that heavy alcohol intake appears to be causally associated with T2DM risk.

Risky drinking and cognitive impairment in community residents aged 50 and over

OBJECTIVES

Alcohol misuse is known to be a risk factor for dementia. This study aimed to explore the association between risky drinking and cognitive impairment in a cohort study of middle aged and older people at risk of dementia.

METHOD

The sample comprised 15,582 people aged 50 and over drawn from the PROTECT study. Risky drinking was defined according to a score of 4 or above on the Alcohol Use Disorders Identification Test (AUDIT). Cognitive function was assessed on visual episodic memory, spatial working memory, verbal working memory and verbal reasoning.

RESULTS

Risky drinkers at baseline were more likely to be younger, male, white British, married, of higher educational status, current or past tobacco smokers and to have moderate to severe depression than non-risky drinkers. Risky drinkers were also more likely to be impaired on self-reported instrumental activities of daily living and subjective cognitive decline. At baseline, risky drinkers were less likely than non-risky drinkers to show impairment on verbal reasoning and spatial working memory but not on visual episodic memory or verbal working memory. Risky drinking at baseline predicted decline in cognitive function on visual episodic memory, verbal reasoning and spatial working memory at 2 year follow-up, but only verbal working memory and spatial working memory remained significant outcomes after controlling for possible confounders.

CONCLUSION

Although of small effect size, the association between risky drinking and impairment on measures of working memory and visuospatial function warrants further examination; particularly given the possibility of partial reversibility in alcohol related cognitive impairment.

Effect of chronic intermittent ethanol vapor exposure on RNA content of brain-derived extracellular vesicles

Extracellular vesicles (EVs) are important players in normal biological function and disease pathogenesis. Of the many biomolecules packaged into EVs, coding and noncoding RNA transcripts are of particular interest for their ability to significantly alter cellular and molecular processes. Here we investigate how chronic ethanol exposure impacts EV RNA cargo and the functional outcomes of these changes. Following chronic intermittent ethanol (CIE) vapor exposure, EVs were isolated from male and female C57BL/6J mouse brain. Total RNA from EVs was analyzed by lncRNA/mRNA microarray to survey changes in RNA cargo following vapor exposure. Differential expression analysis of microarray data revealed a number of lncRNA and mRNA types differentially expressed in CIE compared to control EVs. Weighted gene co-expression network analysis identified multiple male and female specific modules related to neuroinflammation, cell death, demyelination, and synapse organization. To functionally test these changes, whole-cell voltage-clamp recordings were used to assess synaptic transmission. Incubation of nucleus accumbens brain slices with EVs led to a reduction in spontaneous excitatory postsynaptic current amplitude, although no changes in synaptic transmission were observed between control and CIE EV administration. These results indicate that CIE vapor exposure significantly changes the RNA cargo of brain-derived EVs, which have the ability to impact neuronal function.

Cognitive decline and alcohol consumption in the aging population-A longitudinal analysis of the Survey of Health, Ageing and Retirement in Europe

BACKGROUND

Prevalence of cognitive decline and dementia is rising globally, with more than 10 million new cases every year. These conditions cause a significant burden for individuals, their caregivers, and health care systems. As no causal treatment for dementia exists, prevention of cognitive decline is of utmost importance. Notably, alcohol is among the most significant modifiable risk factors for cognitive decline.

METHODS

Longitudinal data across 15 years on 6,967 individuals of the Survey of Health, Ageing and Retirement in Europe were used to analyze the effect of alcohol consumption and further modifiable (i.e., smoking, depression, and educational obtainment) and non-modifiable risk factors (sex and age) on cognitive functioning (i.e., memory and verbal fluency). For this, a generalized estimating equation linear model was estimated for every cognitive test domain assessed.

RESULTS

Consistent results were revealed in all three regression models: A nonlinear association between alcohol consumption and cognitive decline was found-moderate alcohol intake was associated with overall better global cognitive function than low or elevated alcohol consumption or complete abstinence. Furthermore, female sex and higher educational obtainment were associated with better cognitive function, whereas higher age and depression were associated with a decline in cognitive functioning. No significant association was found for smoking.

CONCLUSION

Our data indicate that alcohol use is a relevant risk factor for cognitive decline in older adults. Furthermore, evidence-based therapeutic concepts to reduce alcohol consumption exist and should be of primary interest in prevention measures considering the aging European population.

Genome-wide transcriptomics of the amygdala reveals similar oligodendrocyte-related responses to acute and chronic alcohol drinking in female mice

Repeated excessive alcohol consumption is a risk factor for alcohol use disorder (AUD). Although AUD has been more common in men than women, women develop more severe behavioral and physical impairments. However, relatively few new therapeutics targeting development of AUD, particularly in women, have been validated. To gain a better understanding of molecular mechanisms underlying alcohol intake, we conducted a genome-wide RNA-sequencing analysis in female mice exposed to different modes (acute vs chronic) of ethanol drinking. We focused on transcriptional profiles in the amygdala including the central and basolateral subnuclei, brain areas previously implicated in alcohol drinking and seeking. Surprisingly, we found that both drinking modes triggered similar changes in gene expression and canonical pathways, including upregulation of ribosome-related/translational pathways and myelination pathways, and downregulation of chromatin binding and histone modification. In addition, analyses of hub genes and upstream regulatory pathways revealed that voluntary ethanol consumption affects epigenetic changes via histone deacetylation pathways, oligodendrocyte and myelin function, and the oligodendrocyte-related transcription factor, Sox17. Furthermore, a viral vector-assisted knockdown of Sox17 gene expression in the amygdala prevented a gradual increase in alcohol consumption during repeated accesses. Overall, these results suggest that the expression of oligodendrocyte-related genes in the amygdala is sensitive to voluntary alcohol drinking in female mice. These findings suggest potential molecular targets for future therapeutic approaches to prevent the development of AUD, due to repeated excessive alcohol consumption, particularly in women.

Upregulation of TLR4/MyD88 pathway in alcohol-induced Wernicke’s encephalopathy: Findings in preclinical models and in a postmortem human case

Wernicke’s encephalopathy (WE) is a neurologic disease caused by vitamin B1 or thiamine deficiency (TD), being the alcohol use disorder its main risk factor. WE patients present limiting motor, cognitive, and emotional alterations related to a selective cerebral vulnerability. Neuroinflammation has been proposed to be one of the phenomena that contribute to brain damage. Our previous studies provide evidence for the involvement of the innate immune receptor Toll-like (TLR)4 in the inflammatory response induced in the frontal cortex and cerebellum in TD animal models (animals fed with TD diet [TDD] and receiving pyrithiamine). Nevertheless, the effects of the combination of chronic alcohol consumption and TD on TLR4 and their specific contribution to the pathogenesis of WE are currently unknown. In addition, no studies on TLR4 have been conducted on WE patients since brains from these patients are difficult to achieve. Here, we used rat models of chronic alcohol (CA; 9 months of forced consumption of 20% (w/v) alcohol), TD hit (TDD + daily 0.25 mg/kg i.p. pyrithiamine during 12 days), or combined treatment (CA + TDD) to check the activation of the proinflammatory TLR4/MyD88 pathway and related markers in the frontal cortex and the cerebellum. In addition, we characterized for the first time the TLR4 and its coreceptor MyD88 signature, along with other markers of this proinflammatory signaling such as phospo-NFκB p65 and IκBα, in the postmortem human frontal cortex and cerebellum (gray and white matter) of an alcohol-induced WE patient, comparing it with negative (no disease) and positive (aged brain with Alzheimer’s disease) control subjects for neuroinflammation. We found an increase in the cortical TLR4 and its adaptor molecule MyD88, together with an upregulation of the proinflammatory signaling molecules p-NF-ĸB and IĸBα in the CA + TDD animal model. In the patient diagnosed with alcohol-induced WE, we observed cortical and cerebellar upregulation of the TLR4/MyD88 pathway. Hence, our findings provide evidence, both in the animal model and the human postmortem brain, of the upregulation of the TLR4/MyD88 proinflammatory pathway in alcohol consumption–related WE.

Alcohol consumption among older adults with symptoms of cognitive decline consulting specialist health care

OBJECTIVES

To explore alcohol consumption among older Norwegian adults with symptoms of cognitive decline, assess the agreement between the reports of older adults and their next of kin regarding a person's alcohol consumption, and explore clinical and sociodemographic variables associated with agreement.

METHOD

Alcohol consumption was measured among 3608 older adults consulting specialist health care for symptoms of cognitive decline. Agreement between the participant and their next of kin regarding the participant's alcohol consumption was assessed with a weighted kappa (κ). A logistic regression analysis for hierarchical data was used to explore variables associated with agreement.

RESULTS

Both the participants and their next of kin reported that more than 20% of the participants consumed alcohol 1-3 times a week, and that approximately 10% consumed alcohol four or more times a week. The agreement between the participant's and their next of kin's report regarding the participant's alcohol consumption was high (κ = .852), and variables associated with agreement were no cognitive decline, not drinking alcohol during the last year or ever as reported by the participant, and low agitation scores on a psychiatric assessment.

CONCLUSION

This paper found alcohol consumption among older adults with symptoms of cognitive decline that was above the national average in Norway. This is also the first paper to demonstrate that a next of kin can be a reliable source of information regarding older adults' alcohol consumption. Health personnel should consider these findings when performing medical assessments or developing interventions for older adults.

Effects of ethanol and deferoxamine on rat primary glial cell cultures, in regard with ischemia induced by traumatic spinal cord injury

Although they have been regarded, in the past, as passive support cells, many experimental data have shown that glial cells play a critical role in the development and functioning of the nervous system. Despite the advances that have been made in understanding astrocytes' role in the nervous system's development and function, our knowledge of their interactions with other cells is still limited, albeit neurons are dependent on the trophic support provided by astrocytes release. Materials and Methods. The use of the McCarthy and de Vellis methods for isolating glial cells has been regarded as an essential tool for studying their function. This study aims to evaluate the effects of ethanol and deferoxamine on primary rat glial cell cultures and try to explain, as far as possible, the relevance of such effects for patients with chronic alcoholism and traumatic spinal cord injuries. Discussion. Because glial cells are very important in the functioning of the central nervous system and experiments cannot be performed on human primary nerve cell cultures, we performed an experiment on glial cells harvested from the newborn rat, analyzing the dynamics of IL-6 and TNF alpha on models of suffering in spinal cord injury (hypoxia and thermally stress). Conclusion. Inhibition of TNF alpha synthesis was more important at 7 days posttraumatic in cells with prolonged ethanolic exposure, even if protein levels of IL-6 were elevated (under similar experimental conditions). Thus, we can say that long-term exposure to ethanol of nerve cells can ensure a favorable evolution of medical recovery (by increasing TNF alpha), even if the inflammatory process remains active (shown by elevated IL-6 values). Keywords: ethyl alcohol, deferoxamine, primary glial cells cultures, traumatic Spinal Cord Injury

Neuropsychological Profile of College Students Who Engage in Binge Drinking

This study investigated the neuropsychological profile of college students who engage in binge drinking (BD) using comprehensive neuropsychological tests evaluating verbal/non-verbal memory, executive functions, and attention. Groups were determined based on scores on the Korean version of the Alcohol Use Disorder Identification Test (AUDIT-K) and Alcohol Use Questionnaire (AUQ). There were 79 and 81 participants in the BD and non-BD groups, respectively. We administered the Korean version of the California Verbal Learning Test (K-CVLT) and Rey-Osterrieth Complex Figure Test (RCFT) to evaluate verbal and non-verbal memory, respectively, and measured executive functions using the Wisconsin Card Sorting Test (WCST), Trail-Making Test, Controlled Oral Word Association Test and Stroop Color-Word Test. We administered the d2 test to evaluate attention. Neuropsychological performance was analyzed by multivariate analysis of variance. The BD group showed significantly poorer performance in the long-term free recall condition of the K-CVLT and delayed recall condition of the RCFT and completed significantly fewer categories on the WCST than the non-BD group. In addition, there were significant negative associations among the AUDIT-K total score, AUQ binge score, and long-term free recall score of the K-CVLT. There were significant negative associations between the total AUDIT-K score and delayed recall RCFT score, and between the total AUDIT-K total score and numbers of completed categories on the WCST. These results indicate that college students who participate in BD have difficulties with verbal/non-verbal memory and executive functions, and further suggest that excessive alcohol use could have detrimental effects on the hippocampal-prefrontal circuit even with a relatively short period of alcohol use.

A Dose–Response Relationship of Alcohol Consumption with Risk of Visual Impairment in Korean Adults: The Kangbuk Samsung Health Study

Visual impairment is a global health problem that leads to poor quality of life. The aim of the study was to examine the dose–response relationship between alcohol consumption and incident visual impairment (VI). This longitudinal cohort study consisted of 287,352 Korean adults who attended health screenings between March 2011 and December 2017 and were followed for up to 8.8 years (median, 4.9 years). Participants were categorized based on their average alcohol consumption. VI was defined as bilateral visual acuity (VA) worse than 0.3 logMAR. We identified 8320 cases of new-onset bilateral VI (incidence rate, 6.0/1000 person-years). Increased alcohol intake was positively and dose-dependently associated with elevated incidence of VI (p_trend < 0.001). With lifetime abstinence (reference), the multivariable-adjusted hazard ratios (HRs) (95% confidence intervals (CIs)) for incident VI with alcohol intake of <10, 10 to <20, 20–39.9, and ≥40 g/day were 1.07 (0.96–1.19), 1.15 (1.03–1.30), 1.15 (1.01–1.30), and 1.23 (1.08–1.40), respectively. Frequent binge drinking (≥once/per week) was associated with elevated risk of VI (HRs, 1.22; 95% CIs: 1.13–1.32). Former drinkers, particularly men, were at a higher risk for incident VI than lifetime abstainers. Similar associations were observed on evaluating changes in alcohol consumption and other confounders as time-varying covariates. Alcohol consumption, both in moderation and excess, was associated with increased VI incidence.

A coordinate-based meta-analysis of white matter alterations in patients with alcohol use disorder

INTRODUCTION

Besides the commonly described gray matter (GM) deficits, there is growing evidence of significant white matter (WM) alterations in patients with alcohol use disorder (AUD). WM changes can be assessed using volumetric and diffusive magnetic resonance imaging methods, such as voxel-based morphometry (VBM) and diffusion tensor imaging (DTI). The aim of the present meta-analysis is to investigate the spatial convergence of the reported findings on WM alterations in AUD.

METHODS

Systematic literature search on PubMed and further databases revealed 18 studies eligible for inclusion, entailing a total of 462 AUD patients and 416 healthy controls (up to January 18, 2021). All studies that had used either VBM or DTI whole-brain analyzing methods and reported results as peak-coordinates in standard reference space were considered for inclusion. We excluded studies using approaches non-concordant with recent guidelines for neuroimaging meta-analyses and studies investigating patient groups with Korsakoff syndrome or other comorbid substance use disorders (except tobacco).

RESULTS

Anatomical likelihood estimation (ALE) revealed four significant clusters of convergent macro- and microstructural WM alterations in AUD patients that were assigned to the genu and body of the corpus callosum, anterior and posterior cingulum, fornix, and the right posterior limb of the internal capsule.

DISCUSSION

The changes in WM could to some extent explain the deteriorations in motor, cognitive, affective, and perceptual functions seen in AUD. Future studies are needed to clarify how WM alterations vary over the course of the disorder and to what extent they are reversible with prolonged abstinence.

Disinhibition-Like Behavior Correlates with Frontal Cortex Damage in an Animal Model of Chronic Alcohol Consumption and Thiamine Deficiency

Wernicke-Korsakoff syndrome (WKS) is induced by thiamine deficiency (TD) and mainly related to alcohol consumption. Frontal cortex dysfunction has been associated with impulsivity and disinhibition in WKS patients. The pathophysiology involves oxidative stress, excitotoxicity and inflammatory responses leading to neuronal death, but the relative contributions of each factor (alcohol and TD, either isolated or in interaction) to these phenomena are still poorly understood. A rat model was used by forced consumption of 20% (w/v) alcohol for 9 months (CA), TD hit (TD diet + pyrithiamine 0.25 mg/kg, i.p. daily injections the last 12 days of experimentation (TDD)), and both combined treatments (CA+TDD). Motor and cognitive performance and cortical damage were examined. CA caused hyperlocomotion as a possible sensitization of ethanol-induced excitatory effects and recognition memory deficits. In addition, CA+TDD animals showed a disinhibited-like behavior which appeared to be dependent on TDD. Additionally, combined treatment led to more pronounced alterations in nitrosative stress, lipid peroxidation, apoptosis and cell damage markers. Correlations between injury signals and disinhibition suggest that CA+TDD disrupts behaviors dependent on the frontal cortex. Our study sheds light on the potential disease-specific mechanisms, reinforcing the need for neuroprotective therapeutic approaches along with preventive treatments for the nutritional deficiency in WKS.