Future prospects for biomarkers of alcohol consumption and alcohol-induced disorders

Confounders of Serum Phosphatidylethanol: Role of Red Blood Cell Turnover and Cirrhosis

Purpose

Ethyl glucuronide (EtG), ethyl sulfate (EtS) and phosphatidylethanol (PEth) are considered specific direct biomarkers for detecting alcohol consumption. However, PEth, which is produced in red blood cells (RBC), varies considerably between patients for unknown reasons. We here studied various confounders of PEth elimination including fibrosis after alcohol withdrawal.

Patients and Methods

EtG, EtS and PEth together with routine laboratory and clinical parameters were studied in 100 Caucasian heavy drinkers prior and after alcohol detoxification. In addition, fibrosis stage and degree of steatosis were assessed by transient elastography (Fibroscan, Echosens, Paris).

Results

All three biomarkers were highly correlated (0.61-0.72) with initial serum alcohol levels, but only PEth correlated with daily alcohol consumption. After alcohol withdrawal, PEth significantly decreased within 6.1 days from 1708 to 810 ng/mL (half-life varied from 1.6 to 15.2 days). Both levels of serum alcohol but also EtG and EtS were higher in patients with liver cirrhosis as compared to patients without fibrosis despite comparable alcohol consumption suggesting a decreased alcohol elimination in patients with cirrhosis. PEth was also elevated in cirrhosis but not significantly. In contrast, PEth elimination rate was significantly higher in patients with enhanced RBC turnover and signs of alcohol-mediated hemolytic anemia with elevated ferritin, LDH and increased mean corpuscular volume (MCV).

Conclusion

We here demonstrate that alcohol elimination is decreased in patients with liver cirrhosis. In patients with cirrhosis, PEth levels are both affected in opposite directions by enhanced red blood cell turnover and elevated alcohol levels. Our data have important implications for the use and interpretation of PEth in the clinical setting.

[Indicators of spontaneous behavior of rhesus monkeys with short-term course alcohol self-administration under free choice]

OBJECTIVE

To analyze spontaneous behavior in 36 male rhesus macaques during formation of alcoholic motivation under free choice.

MATERIAL AND METHODS

The model composed the initiation stage with the provision of an aqueous ethanol solution of increasing concentration from 1 to 4% with a sweetener and restricted access to the tap water supply and the subsequent stage of the formation of alcoholic motivation with a free choice between 4% ethanol solution without sweetener and water. The behavior was recorded by the «One-Zero» method with ethogram compiled in accordance with the behavioral peculiarities of rhesus monkeys when housed individually. Three subgroups of high, medium and low-level ethanol consumption were distinguished.

RESULTS

In the subgroup of high ethanol consumption median consumption was 1.70 g/kg/day at initiation (p<0.05, compared to other subgroups) and 1.79 g/kg/day (p<0.05) at free choice stage. Animals of high consumption subgroup had significantly higher frequency being at the cage bottom and in a sitting posture. We observed significant changes in a number of indicators of spontaneous behavior depending on the level of ethanol consumption, which included displacement behavior, stereotypic behavior and posture of animals. In the high consumption subgroup, there was a significant increase in the frequency of stereotypic behavior, atypical behavior, being on four legs, as well as a decrease in the frequency of being at the back side of the cage and of displacement behavior. At the same time, the inhibitory effect of ethanol on the hypothalamic-pituitary-adrenal system was revealed.

CONCLUSION

In the model of free choice alcohol self-administration rhesus monkeys demonstrate a significant change in a number of indicators of spontaneous behavior depending on the level of ethanol consumption, which includes displacement, stereotypic behaviors and animal posture.

Combination of the CAGE and serum gamma-glutamyl transferase: an effective screening tool for alcohol use disorder and alcohol dependence

Purpose: The CAGE is a convenient test for alcohol-related disorder due to its brevity, but it is not as effective as the alcohol use disorders identification test (AUDIT). Gamma-glutamyl transferase (GGT) is an objective blood biochemical marker of excessive alcohol intake; however, it has low sensitivity. This study tested the performance of the combined use of CAGE and GGT to screen problem drinking (PD), alcohol use disorder (AUD), and alcohol dependence (AD). Methods: A total of 394 subjects composed of 91 normal controls and 303 subjects with PD were enrolled in this study. Of the PD subjects, 147 were diagnosed with AUD (77 alcohol abuse and 70 AD). A series of multiple logistic regression models for PD, AUD, and AD discrimination were used to obtain new combined CAGE and GGT scores after adjusting for age and gender (CAGE+GGT). A receiver operating characteristic curve analysis was conducted to determine how well the CAGE+GGT score discriminated between individuals with PD, AUD, and AD. Results: The discrimination accuracy of the AUDIT for PD was significantly better than that of the CAGE or the CAGE+GGT (z=6.927, p<0.0001; z=5.301, p<0.0001, respectively). The CAGE and the CAGE+GGT were better than the AUDIT at discriminating AUD (z=2.535, p=0.0112; z=2.894, p=0.0038, respectively). The discrimination accuracy of the AUDIT for AD was significantly better than that of the CAGE and GGT (z=3.233, p=0.0012; z=6.529, p<0.0001, respectively), but the CAGE+GGT was comparable with the AUDIT (z=1.652, p=0.0985). Conclusion: Our findings support the combined use of the CAGE questionnaire and serum GGT level as a sensitive and useful tool for AD screening.

Extracellular vesicles as potential biomarkers for alcohol- and drug-induced liver injury and their therapeutic applications

Extracellular vesicles (EVs) are small membranous vesicles originating from various cells and tissues, including the liver parenchymal hepatocytes and nonparenchymal cells such as Kupffer and stellate cells. Recently, the pathophysiological role of EVs, such as exosomes and microvesicles, has been increasingly recognized based on their properties of intercellular communications. These EVs travel through the circulating blood and interact with specific cells and then deliver their cargos such as nucleic acids and proteins into recipient cells. In addition, based on their stabilities, circulating EVs from body fluids such as blood, cerebrospinal fluid, urine, saliva, semen, breast milk and amniotic fluids are being studied as a valuable source of potential biomarkers for providing information about the physiological status of original cells or tissues. In addition, EVs are considered potential therapeutic agents due to their ability for intercellular communications between different cell types within the liver and between various organs through transfer of their cargos. In this review, we have briefly described recent advances in the characteristics and pathophysiological roles of EVs in alcoholic liver disease (ALD) or drug-induced liver injury (DILI) and discuss their advantages in the discovery of potential biomarkers and therapeutic agents.

A review on EEG-based methods for screening and diagnosing alcohol use disorder

The screening test for alcohol use disorder (AUD) patients has been of subjective nature and could be misleading in particular cases such as a misreporting the actual quantity of alcohol intake. Although the neuroimaging modality such as electroencephalography (EEG) has shown promising research results in achieving objectivity during the screening and diagnosis of AUD patients. However, the translation of these findings for clinical applications has been largely understudied and hence less clear. This study advocates the use of EEG as a diagnostic and screening tool for AUD patients that may help the clinicians during clinical decision making. In this context, a comprehensive review on EEG-based methods is provided including related electrophysiological techniques reported in the literature. More specifically, the EEG abnormalities associated with the conditions of AUD patients are summarized. The aim is to explore the potentials of objective techniques involving quantities/features derived from resting EEG, event-related potentials or event-related oscillations data.

The association between alcohol abuse and neuroendocrine system dysregulation: Race differences in a National sample

Health outcomes, including chronic disease and mortality, attributed to or associated with alcohol abuse are discrepant between African Americans and Whites. To date, the topic is not fully understood and few studies conducted have used biomarker indicators of health. We investigated whether the association between alcohol abuse and biomarkers of the neuroendocrine system vary between black or African American and White respondents aged 34-84 from the Midlife in the United States Study (MIDUS) II (2004-2006) (n=1129). Alcohol abuse was assessed with a modified version of the Michigan Alcohol Screening Test. Ordinary least squared (OLS) regression was used to evaluate whether race moderated the associations between alcohol abuse and four biomarkers-urinary cortisol and serum dehydroepiandrosterone sulfate (DHEA-S), epinephrine and norepinephrine-and two composite summary scores, each consisting of two components that characterize the hypothalamic pituitary adrenal (HPA)-axis and sympathetic nervous systems (SNS), respectively. Covariates included age, sex, education, income, current drinking, smoking, exercise, fast food consumption, heart disease, blood pressure, diabetes, body mass index, medication use, anxiety/depression, sleep duration, and cholesterol markers. Race significantly moderated the associations between alcohol abuse and norepinephrine concentration (χ² [1]=4.48, p=0.034) and the SNS composite score (χ² [1]=5.83, p=0.016). Alcohol abuse was associated with higher mean norepinephrine levels (b=0.26, standard error (SE)=0.12, p=0.034) and SNS composite score (b=0.23, SE=0.11, p=0.016) for African Americans compared to Whites. Interestingly, for Whites a paradoxical association between alcohol abuse, norepinephrine and SNS levels was observed; those who abused alcohol had lower mean norepinephrine levels than non-abusers. Race differences in neuroendocrine response could be biological pathways that contribute the excess risk of chronic disease and mortality attributed to alcohol abuse among African Americans compared to Whites. Replication of these analyses in larger cohorts are warranted in addition to further studies of underlying mechanisms among Blacks and Whites separately.

The Utility of Commonly Used Laboratory Tests to Screen for Excessive Alcohol Use in Clinical Practice

BACKGROUND

This current study was undertaken to carefully assess the accuracy of routinely used laboratory tests in detecting excessive/recent alcohol use. We also determined the kinetics of these markers in subjects who underwent an intensive alcohol rehabilitation program.

METHODS

The study cohort consisted of 210 nonexcessive drinkers, 272 excessive drinkers, and 76 with alcoholic cirrhosis. To determine the kinetics of these markers during alcohol abstinence, we followed 45 subjects with history of excessive alcohol use for 12 weeks during the intensive alcohol treatment program.

RESULTS

Percentage of carbohydrate deficient transferrin (%CDT) provided the highest diagnostic performance (area under the curve [AUC] 0.77) followed by gamma-glutamyl transferase (GGT) (AUC 0.68) to detect excessive drinkers. The percentage of excessive drinkers with aspartate aminotransferase:alanine aminotransferase (AST:ALT) > 2 was only 2%, whereas 51% of subjects with alcoholic cirrhosis had AST:ALT > 2. In the multivariate analysis, the levels of GGT and %CDT were associated with the level of alcohol consumed during the past 30 days. The levels of GGT, mean corpuscular volume (MCV), and %CDT were significantly lower compared to those at baseline before alcohol rehabilitation, whereas the AST, ALT, and AST:ALT ratio were unchanged. The percent reduction was ~2.7% (for MCV), 19% (for GGT), and 43% (for %CDT) at the end of the 12-week follow-up compared to the baseline.

CONCLUSIONS

%CDT are useful markers to screen for excessive alcohol use and for follow-up of abstinence. Most subjects with excessive alcohol use do not have a high AST:ALT ratio. Rather, the AST:ALT > 2 is suggestive of alcoholic cirrhosis. The performance of the %CDT to screen for heavy alcohol use is still not ideal. Further research to identify the noninvasive marker(s) (i.e., using proteomic or metabolomics approach) should be considered.

Novel serum biomarkers for detection of excessive alcohol use

BACKGROUND

Construct interview that correctly identifies those with alcohol use disorder have limitation, especially when the subjects are motivated to minimize the magnitude of drinking behavior. Current laboratory tests to detect excessive alcohol consumption are limited by marginal sensitivity/specificity. Excessive drinking has been shown to affect several organ systems, which may be reflected in changes in quantity of plasma proteins. Our aim was to employ novel proteomic analyses to identify potential markers for excessive alcohol use.

METHODS

A prospective case-control study included 49 controls and 54 excessive drinkers (discovery cohort). The serum proteomic analyses in these subjects were performed, and the results were tested in the verification cohort (40 controls and 40 excessive drinkers).

RESULTS

Using the appropriate cutoff and confirmation with ELISA, we identified 4 proteins which were significantly elevated in the serum of excessive drinkers: AT-rich interactive domain-containing protein 4B (ARID4B), phosphatidylcholine-sterol acyltransferase (LCAT), hepatocyte growth factor-like protein (MST1), and ADP-ribosylation factor 6 (ARL6). The performance of the conventional markers (aspartate aminotransferase [AST], alanine aminotransferase [ALT], gamma-glutamyl transpeptidase [GGT], percentage of carbohydrate-deficient transferrin [%CDT], and mean corpuscular volume [MCV]) discriminating between excessive alcohol use and controls had an area under the curve (AUC) ranging from 0.21 (ALT) to 0.67 (MCV). The AUC of these novel proteins showed the improvement in the detection of excessive drinkers compared to conventional laboratory tests, ranging from 0.73 (for ARID4B) to 0.86 (for ARL6).

CONCLUSIONS

We have identified 4 novel proteins that can discern subjects with excessive alcohol use. Further studies are needed to determine the clinical implications of these markers to detect excessive alcohol use and confirm abstinence.

Predictors of motivation to change in mandated college students following a referral incident

The purpose of present study was to understand factors that are related to a desire or motivation to change (MTC) alcohol use in a sample of college students mandated to receive an alcohol intervention. We examined characteristics of and reactions to the referral event, typical alcohol use involvement, and alcohol beliefs about the perceived importance of drinking in college assessed by the College Life Alcohol Salience Scale (CLASS; Osberg et al., 2010) as predictors of MTC following referral to an alcohol intervention. College students (N = 932) who presented for a mandatory alcohol intervention following a referral event (e.g., citation for underage drinking, medical attention for an alcohol-related incident, or driving under the influence) completed an assessment prior to receiving an alcohol intervention. Higher perceived aversiveness of the referral event and higher personal responsibility one felt for the occurrence of the event were positively related to higher MTC. Although alcohol beliefs about the role of drinking in college were not significantly related to either event aversiveness or responsibility, it was negatively related to MTC even after controlling for alcohol use involvement variables. Alcohol beliefs about the role of drinking in college represent an important construct that is related to increased alcohol use and alcohol-related problems and decreased MTC in a sample of college students. Interventions aimed at reducing alcohol beliefs about the role of drinking in college may be an effective strategy to reduce alcohol use and alcohol-related problems by college students.

Proteomic approaches and identification of novel therapeutic targets for alcoholism

Recent studies have shown that gene regulation is far more complex than previously believed and does not completely explain changes at the protein level. Therefore, the direct study of the proteome, considerably different in both complexity and dynamicity to the genome/transcriptome, has provided unique insights to an increasing number of researchers. During the past decade, extraordinary advances in proteomic techniques have changed the way we can analyze the composition, regulation, and function of protein complexes and pathways underlying altered neurobiological conditions. When combined with complementary approaches, these advances provide the contextual information for decoding large data sets into meaningful biologically adaptive processes. Neuroproteomics offers potential breakthroughs in the field of alcohol research by leading to a deeper understanding of how alcohol globally affects protein structure, function, interactions, and networks. The wealth of information gained from these advances can help pinpoint relevant biomarkers for early diagnosis and improved prognosis of alcoholism and identify future pharmacological targets for the treatment of this addiction.

A modified random walk door-to-door recruitment strategy for collecting social and biological data relating to mental health, substance use, addiction, and violence problems in a Canadian community

AIMS

To describe a modified "random walk" door-to-door recruitment strategy used to obtain a random community sample for participation in a study relating to mental health, substance use, addiction, and violence (MSAV) problems and involving the collection of both self-report and biological (hair and saliva) data. This paper describes study protocols, response rates for the study and for the provision of biological data, and possible further applications for this data collection method.

DESIGN

A two-stage cluster sample was derived from the 2006 Canadian census sampling frame for a small Ontario community, based on the random selection of city blocks as the primary sampling units and households as the secondary sampling units.

SETTING

A small city in Ontario, Canada.

PARTICIPANTS

A general population sample of 92 participants selected randomly from households using Kish tables.

MEASURES

A computerized questionnaire was administered to obtain self-report data on MSAV problems. Saliva was collected to study genetic vulnerabilities to MSAV problems, and hair was collected to examine stress levels (via the hormone cortisol) as they relate to MSAV problems.

FINDINGS

The study showed a response rate of 50% and a high rate of provision of biological samples (over 95%).

CONCLUSIONS

Modified random walk methodologies involving face-to-face recruitment may represent a useful approach for obtaining general population samples for studies of MSAV problems, particularly those involving the collection of biological samples. Further studies are needed to assess whether this approach leads to better response rates and improved estimates compared to other survey methods used in research on substance use.

Liver proteomics in progressive alcoholic steatosis

Fatty liver is an early stage of alcoholic and nonalcoholic liver disease (ALD and NALD) that progresses to steatohepatitis and other irreversible conditions. In this study, we identified proteins that were differentially expressed in the livers of rats fed 5% ethanol in a Lieber-DeCarli diet daily for 1 and 3 months by discovery proteomics (two-dimensional gel electrophoresis and mass spectrometry) and non-parametric modeling (Multivariate Adaptive Regression Splines). Hepatic fatty infiltration was significantly higher in ethanol-fed animals as compared to controls, and more pronounced at 3 months of ethanol feeding. Discovery proteomics identified changes in the expression of proteins involved in alcohol, lipid, and amino acid metabolism after ethanol feeding. At 1 and 3 months, 12 and 15 different proteins were differentially expressed. Of the identified proteins, down regulation of alcohol dehydrogenase (-1.6) at 1 month and up regulation of aldehyde dehydrogenase (2.1) at 3 months could be a protective/adaptive mechanism against ethanol toxicity. In addition, betaine-homocysteine S-methyltransferase 2 a protein responsible for methionine metabolism and previously implicated in fatty liver development was significantly up regulated (1.4) at ethanol-induced fatty liver stage (1 month) while peroxiredoxin-1 was down regulated (-1.5) at late fatty liver stage (3 months). Nonparametric analysis of the protein spots yielded fewer proteins and narrowed the list of possible markers and identified d-dopachrome tautomerase (-1.7, at 3 months) as a possible marker for ethanol-induced early steatohepatitis. The observed differential regulation of proteins have potential to serve as biomarker signature for the detection of steatosis and its progression to steatohepatitis once validated in plasma/serum.

Protein biomarkers of alcohol abuse

Alcohol abuse can lead to a number of health and social issues. Our current inability to accurately assess long-term drinking behaviors is an important obstacle to its diagnosis and treatment. Biomarkers for chronic alcohol consumption have made a number of important advances but have yet to become highly accurate and as accepted as objective tests for other diseases. Thus, there is a crucial need for the development of more sensitive and specific markers of alcohol abuse. Recent advancements in proteomic technologies have greatly increased the potential for alcohol abuse biomarker discovery. Here, the authors review established and novel protein biomarkers for long-term alcohol consumption and the proteomic technologies that have been used in their study.

Phosphatidylethanol (PEth) as a biomarker of alcohol consumption in HIV-positive patients in sub-Saharan Africa

BACKGROUND

Alcohol is heavily consumed in sub-Saharan Africa and affects HIV transmission and treatment and is difficult to measure. Our goal was to examine the test characteristics of a direct metabolite of alcohol consumption, phosphatidylethanol (PEth).

METHODS

Persons infected with HIV were recruited from a large HIV clinic in southwestern Uganda. We conducted surveys and breath alcohol concentration (BRAC) testing at 21 daily home or drinking establishment visits, and blood was collected on day 21 (n = 77). PEth in whole blood was compared with prior 7-, 14-, and 21-day alcohol consumption.

RESULTS

(i) The receiver operator characteristic area under the curve (ROC-AUC) was highest for PEth versus any consumption over the prior 21 days (0.92; 95% confidence interval [CI]: 0.86 to 0.97). The sensitivity for any detectable PEth was 88.0% (95% CI: 76.0 to 95.6) and the specificity was 88.5% (95% CI: 69.8 to 97.6). (ii) The ROC-AUC of PEth versus any 21-day alcohol consumption did not vary with age, body mass index, CD4 cell count, hepatitis B virus infection, and antiretroviral therapy status, but was higher for men compared with women (p = 0.03). (iii) PEth measurements were correlated with several measures of alcohol consumption, including number of drinking days in the prior 21 days (Spearman r = 0.74, p < 0.001) and BRAC (r = 0.75, p < 0.001).

CONCLUSIONS

The data add support to the body of evidence for PEth as a useful marker of alcohol consumption with high ROC-AUC, sensitivity, and specificity. Future studies should further address the period and level of alcohol consumption for which PEth is detectable.

Serotonin transporter genomic biomarker for quantitative assessment of ondansetron treatment response in alcoholics

Paucity of sensitive biomarkers to quantify transient changes in alcohol consumption level remains a critical barrier for the development of efficacious therapeutic agents to treat alcoholism. Recently, in an 11-week, randomized, placebo-controlled, double-blind trial of 283 alcohol-dependent individuals, we demonstrated that ondansetron was efficacious at reducing the severity of drinking (measured as drinks per drinking day; DDD) in alcoholics carrying the LL compared with the LS/SS genotype of the serotonin transporter gene, 5'-HTTLPR. Using peripheral blood samples from a cohort of 41 of these subjects, we determined whether there was a relationship between mRNA expression level of the 5'-HTTLPR genotypes (measured at weeks 0, 4, and 11) and self-reported alcohol consumption following treatment with either ondansetron (4 μg/kg twice daily; N = 19) or placebo (N = 22). Using a mixed-effects linear regression model, we analyzed the effects of DDD and 5'-HTTLPR genotypes on mRNA expression levels within and between the ondansetron and placebo groups. We found a significant three-way interaction effect of DDD, 5'-HTTLPR genotypes, and treatment on mRNA expression levels (p = 0.0396). Among ondansetron but not placebo recipients, there was a significant interaction between DDD and 5'-HTTLPR genotype (p = 0.0385 and p = 0.7938, respectively). In the ondansetron group, DDD was associated positively with mRNA levels at a greater rate of expression alteration per standard drink in those with the LL genotype (slope = +1.1698 in ln scale). We suggest that the combination of the LL genotype and 5'-HTTLPR mRNA expression levels might be a promising and novel biomarker to quantify drinking severity in alcoholics treated with ondansetron.

Alcohol intake

Alcohol consumption and its association with health or illness states are of great interest from the nutritional genomics point of view. This interest is centered not only on investigating the genetic variants that can modulate the effects of alcoholic beverages on different intermediate and final disease phenotypes (mainly cardiovascular diseases and cancer), but also on finding out how the genome influences the amount of alcohol consumed and consumption habits. This chapter reviews the latest findings on alcohol consumption trends, the methodological limitations in the analysis of alcohol consumption, and the main genes and polymorphisms related to alcohol intake, including the inconsistent results from genome-wide association studies (GWASs). It also reviews the effects of alcohol consumption on cardiovascular diseases and cancer and the studies analyzing the interactions between different genetic polymorphisms and alcohol in phenotypes related to these diseases, discussing the studies' advantages and limitations as well as future research perspectives.

Plasma proteomic alterations in non-human primates and humans after chronic alcohol self-administration

Objective diagnostics of excessive alcohol use are valuable tools in the identification and monitoring of subjects with alcohol use disorders. A number of potential biomarkers of alcohol intake have been proposed, but none have reached widespread clinical usage, often due to limited diagnostic sensitivity and specificity. In order to identify novel potential biomarkers, we performed proteomic biomarker target discovery in plasma samples from non-human primates that chronically self-administer high levels of ethanol. Two-dimensional difference in-gel electrophoresis (2D-DIGE) was used to quantify plasma proteins from within-subject samples collected before exposure to ethanol and after 3 months of excessive ethanol self-administration. Highly abundant plasma proteins were depleted from plasma samples to increase proteomic coverage. Altered plasma levels of serum amyloid A4 (SAA4), retinol-binding protein, inter-alpha inhibitor H4, clusterin, and fibronectin, identified by 2D-DIGE analysis, were confirmed in unmanipulated, whole plasma from these animals by immunoblotting. Examination of these target plasma proteins in human subjects with excessive alcohol consumption (and control subjects) revealed increased levels of SAA4 and clusterin and decreased levels of fibronectin compared to controls. These proteins not only serve as targets for further development as biomarker candidates or components of biomarker panels, but also add to the growing understanding of dysregulated immune function and lipoprotein metabolism with chronic, excessive alcohol consumption.

Lipidomic changes in rat liver after long-term exposure to ethanol

Alcoholic liver disease (ALD) is a serious health problem with significant morbidity and mortality. In this study we examined the progression of ALD along with lipidomic changes in rats fed ethanol for 2 and 3 months to understand the mechanism, and identify possible biomarkers. Male Fischer 344 rats were fed 5% ethanol or caloric equivalent of maltose-dextrin in a Lieber-DeCarli diet. Animals were killed at the end of 2 and 3 months and plasma and livers were collected. Portions of the liver were fixed for histological and immunohistological studies. Plasma and the liver lipids were extracted and analyzed by nuclear magnetic resonance (NMR) spectroscopy. A time dependent fatty infiltration was observed in the livers of ethanol-fed rats. Mild inflammation and oxidative stress were observed in some ethanol-fed rats at 3 months. The multivariate and principal component analysis of proton and phosphorus NMR spectroscopy data of extracted lipids from the plasma and livers showed segregation of ethanol-fed groups from the pair-fed controls. Significant hepatic lipids that were increased by ethanol exposure included fatty acids and triglycerides, whereas phosphatidylcholine (PC) decreased. However, both free fatty acids and PC decreased in the plasma. In liver lipids unsaturation of fatty acyl chains increased, contrary to plasma, where it decreased. Our studies confirm that over-accumulation of lipids in ethanol-induced liver steatosis accompanied by mild inflammation on long duration of ethanol exposure. Identified metabolic profile using NMR lipidomics could be further explored to establish biomarker signatures representing the etiopathogenesis, progression and/or severity of ALD.

Psoriasis and unreported excessive alcohol intake--a simple screening approach

Psoriasis is a chronic immune-mediated skin disease of complex aetiology. Alcohol overuse has long been suspected to contribute to psoriasis pathology, and the knowledge of individual's drinking pattern may be of substantial importance for managing the disease. Unfortunately, a number of patients fail to admit to their true alcohol consumption and there is no single sign, symptom or laboratory parameter adequate for alcohol abuse diagnosis. However, there are some laboratory findings that, when present, should raise physician's suspicion that alcohol may be a problem. The aim of this article was to present simple, widely available and relatively reliable laboratory markers that might effectively assist physicians in establishing patient's drinking status. A possible screening approach is illustrated by two distinct reports of psoriatic patients who initially concealed having the problem with alcohol.

Molecular targets of alcohol action: Translational research for pharmacotherapy development and screening

Alcohol abuse and dependence are multifaceted disorders with neurobiological, psychological, and environmental components. Research on other complex neuropsychiatric diseases suggests that genetically influenced intermediate characteristics affect the risk for heavy alcohol consumption and its consequences. Diverse therapeutic interventions can be developed through identification of reliable biomarkers for this disorder and new pharmacological targets for its treatment. Advances in the fields of genomics and proteomics offer a number of possible targets for the development of new therapeutic approaches. This brain-focused review highlights studies identifying neurobiological systems associated with these targets and possible pharmacotherapies, summarizing evidence from clinically relevant animal and human studies, as well as sketching improvements and challenges facing the fields of proteomics and genomics. Concluding thoughts on using results from these profiling technologies for medication development are also presented.

Advancing alcohol biomarkers research

Biomarkers to detect past alcohol use and identify alcohol-related diseases have long been pursued as important tools for research into alcohol use disorders as well as for clinical and treatment applications and other settings. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) sponsored a workshop titled "Workshop on Biomarkers for Alcohol-Induced Disorders" in June 2008. The intent of this workshop was to review and discuss recent progress in the development and implementation of biomarkers for alcohol use and alcohol-related disorders with a goal to formulate a set of recommendations to use to stimulate and advance research progress in this critical area of alcoholism research. Presentations at this workshop reviewed the current status of alcohol biomarkers, providing a summary of the history of biomarkers and the major goals of alcohol biomarker research. Moreover, presentations provided a comprehensive overview of the current status of several well-recognized biomarkers of alcohol use, a summary of recent studies to characterize novel biomarkers and their validation, along with perspectives and experiences from other NIH institutes and from other federal agencies and industry, related to regulatory issues. Following these presentations, a panel discussion focused on a set of issues presented by the organizers of this workshop. These discussion points addressed: (i) issues related to strategies to be adopted to stimulate biomarker discovery and application, (ii) the relevance of animal studies in biomarker development and the status of biomarkers in basic science studies, and (iii) issues related to the opportunities for clinical and commercial applications. This article summarizes these perspectives and highlights topics that constituted the basis for recommendations to enhance alcohol biomarker research.