Renin and aldosterone but not the natriuretic peptide correlate with obsessive craving in medium-term abstinent alcohol-dependent patients: a longitudinal study

Management of alcohol use disorder: a gastroenterology and hepatology-focused perspective

Alcohol use disorder is a prevalent and major but preventable cause of morbidity and mortality worldwide, causing several important health consequences, including chronic liver disease. Despite its substantial effects, most clinicians do not adequately assess alcohol intake in clinical practice, and there are several barriers to providing integrated management to patients with alcohol use disorder. Standardised questionnaires, such as the Alcohol Use Identification Test (AUDIT), can facilitate the identification of individuals at risk of alcohol use disorder, and alcohol biomarkers such as phosphatidylethanol aid in quantifying levels of alcohol consumption. Non-pharmacological interventions-including brief interventions, twelve-step facilitation, motivational enhancement therapy, contingency management, and cognitive behavioural therapy-are effective for patients with alcohol use disorder, regardless of the presence of advanced liver disease. Pharmacological treatments should be considered according to the severity of liver disease and other comorbidities, safety profile, and local availability. The management of patients with alcohol use disorder and associated liver disease should ideally be performed in the setting of integrated multidisciplinary teams.

Mineralocorticoid receptor antagonism partially prevents dysfunction of T cell maturation in rats chronically treated with ethanol

Ethanol consumption induces thymic atrophy and affects T cell maturation in the thymus. However, the mechanisms underlying such effects still need to be fully understood. We attempted to investigate the role of mineralocorticoid receptors (MR) on ethanol-induced thymic atrophy, T cell maturation dysfunction, and the role of oxidative stress in such responses. Male Wistar Hannover rats were treated with ethanol (20%; in volume ratio) and/or potassium canrenoate, an antagonist of MR (MRA; 30 mg/kg/day, gavage) for five weeks. Blockade of MR prevented ethanol-induced increases in the number of double-positive (CD4+CD8+), CD8+ single-positive (CD4-CD8+), CD4+ single-positive (CD4+CD8-), and Foxp3+CD4+ (Treg) cells in the thymus. Ethanol increased NOX2-derived superoxide (O2•-), lipoperoxidation, and superoxide dismutase (SOD) activity in the thymus. Pretreatment with the MRA fully prevented these responses. Apocynin, an antioxidant, prevented ethanol-induced increases in the number of double-positive and CD8+ single-positive cells but failed to prevent the rise in the number of CD4+ single-positive and Treg cells induced by ethanol. Apocynin, but not the MRA, prevented thymic atrophy induced by ethanol. Our findings provided novel evidence for the participation of MR in thymic dysfunction induced by ethanol consumption. Oxidative stress mediates the increase in double-positive and CD8+ single-positive cells in response to MR activation, while positive regulation of CD4+ single-positive and Treg cells is independent of oxidative stress. Oxidative stress is a significant mechanism of thymic atrophy associated with ethanol consumption, but this response is independent of MR activation.

Novel medications for problematic alcohol use

Alcohol-related harm, a major cause of disease burden globally, affects people along a spectrum of use. When a harmful pattern of drinking is present in the absence of significant behavioral pathology, low-intensity brief interventions that provide information about health consequences of continued use provide large health benefits. At the other end of the spectrum, profound behavioral pathology, including continued use despite knowledge of potentially fatal consequences, warrants a medical diagnosis, and treatment is strongly indicated. Available behavioral and pharmacological treatments are supported by scientific evidence but are vastly underutilized. Discovery of additional medications, with a favorable balance of efficacy versus safety and tolerability can improve clinical uptake of treatment, allow personalized treatment, and improve outcomes. Here, we delineate the clinical conditions when pharmacotherapy should be considered in relation to the main diagnostic systems in use and discuss clinical endpoints that represent meaningful clinical benefits. We then review specific developments in three categories of targets that show promise for expanding the treatment toolkit. GPCRs remain the largest category of successful drug targets across contemporary medicine, and several GPCR targets are currently pursued for alcohol-related indications. Endocrine systems are another established category, and several promising targets have emerged for alcohol indications. Finally, immune modulators have revolutionized treatment of multiple medical conditions, and they may also hold potential to produce benefits in patients with alcohol problems.

Role of aldosterone and mineralocorticoid receptor (MR) in addiction: A scoping review

Preclinical and human studies suggest a role of aldosterone and mineralocorticoid receptor (MR) in addiction. This scoping review aimed to summarize (1) the relationship between alcohol and other substance use disorders (ASUDs) and dysfunctions of the aldosterone and MR, and (2) how pharmacological manipulations of MR may affect ASUD-related outcomes. Our search in four databases (MEDLINE, Embase, Web of Science, and Cochrane Library) indicated that most studies focused on the relationship between aldosterone, MR, and alcohol (n = 30), with the rest focused on opioids (n = 5), nicotine (n = 9), and other addictive substances (n = 9). Despite some inconsistencies, the overall results suggest peripheral and central dysregulations of aldosterone and MR in several species and that these dysregulations depended on the pattern of drug exposure and genetic factors. We conclude that MR antagonism may be a promising target in ASUD, yet future studies are warranted.

New insights into the molecular basis of alcohol abstinence and relapse in alcohol-associated liver disease

Alcohol use disorder remains a significant public health concern, affecting around 5% of adults worldwide. Novel pathways of damage have been described during the last years, providing insight into the mechanism of injury due to alcohol misuse beyond the direct effect of ethanol byproducts on the liver parenchyma and neurobehavioral mechanisms. Thus, the gut-liver-brain axis and immune system involvement could be therapeutic targets for alcohol use disorder. In particular, changes in gut microbiota composition and function, and bile acid homeostasis, have been shown with alcohol consumption and cessation. Alcohol can also directly disrupt intestinal and blood-brain barriers. Activation of the immune system can be triggered by intestinal barrier dysfunction and translocation of bacteria, pathogen-associated molecular patterns (such as lipopolysaccharide), cytokines, and damage-associated molecular patterns. These factors, in turn, promote liver and brain inflammation and the progression of liver fibrosis. Other involved mechanisms include oxidative stress, apoptosis, autophagy, and the release of extracellular vesicles and miRNA from hepatocytes. Potential therapeutic targets include gut microbiota (probiotics and fecal microbiota transplantation), neuroinflammatory pathways, as well as neuroendocrine pathways, for example, the ghrelin system (ghrelin receptor blockade), incretin mimetics (glucagon-like peptide-1 analogs), and the mineralocorticoid receptor system (spironolactone). In addition, support with psychological and behavioral treatments is essential to address the multiple dimensions of alcohol use disorder. In the future, a personalized approach considering these novel targets can contribute to significantly decreasing the alcohol-associated burden of disease.

Mineralocorticoid receptors contribute to ethanol-induced vascular hypercontractility through reactive oxygen species generation and up-regulation of cyclooxygenase 2

The effects on blood pressure produced byethanol consumption include both vasoconstriction and activation of the renin-angiotensin-aldosterone system (RAAS), although the detailed relationship between these processes is yet to be accomplished. Here, we sought to investigate the contribution of mineralocorticoid receptors (MR) to ethanol-induced hypertension and vascular hypercontractility. We analyzed blood pressure and vascular function of male Wistar Hannover rats treated with ethanol for five weeks. The contribution of the MR pathway to the cardiovascular effects of ethanol was evaluated with potassium canrenoate, a MR antagonist (MRA). Blockade of MR prevented ethanol-induced hypertension and hypercontractility of endothelium-intact and -denuded aortic rings. Ethanol up-regulated cyclooxygenase (COX)2 and augmented vascular levels of both reactive oxygen species (ROS) and thromboxane (TX)B₂, a stable metabolite of TXA₂. These responses were abrogated by MR blockade. Hyperreactivity to phenylephrine induced by ethanol consumption was reversed by tiron [a scavenger of superoxide (O₂∙^-)], SC236 (a selective COX2 inhibitor) or SQ29548 (an antagonist of TP receptors). Treatment with the antioxidant apocynin prevented the vascular hypercontractility, as well as the increases in COX2 expression and TXA₂ production induced by ethanol consumption. Our study has identified novel mechanisms through which ethanol consumption promotes its deleterious effects in the cardiovascular system. We provided evidence for a role of MR in the vascular hypercontractility and hypertension associated with ethanol consumption. The MR pathway triggers vascular hypercontractility through ROS generation, up-regulation of COX2 and overproduction of TXA₂, which will ultimately induce vascular contraction.

Spironolactone as a potential new pharmacotherapy for alcohol use disorder: convergent evidence from rodent and human studies

Evidence suggests that spironolactone, a nonselective mineralocorticoid receptor (MR) antagonist, modulates alcohol seeking and consumption. Therefore, spironolactone may represent a novel pharmacotherapy for alcohol use disorder (AUD). In this study, we tested the effects of spironolactone in a mouse model of alcohol drinking (drinking-in-the-dark) and in a rat model of alcohol dependence (vapor exposure). We also investigated the association between spironolactone receipt for at least 60 continuous days and change in self-reported alcohol consumption, using the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C), in a pharmacoepidemiologic cohort study in the largest integrated healthcare system in the US. Spironolactone dose-dependently reduced the intake of sweetened or unsweetened alcohol solutions in male and female mice. No effects of spironolactone were observed on drinking of a sweet solution without alcohol, food or water intake, motor coordination, alcohol-induced ataxia, or blood alcohol levels. Spironolactone dose-dependently reduced operant alcohol self-administration in dependent and nondependent male and female rats. In humans, a greater reduction in alcohol consumption was observed among those who received spironolactone, compared to propensity score-matched individuals who did not receive spironolactone. The largest effects were among those who reported hazardous/heavy episodic alcohol consumption at baseline (AUDIT-C ≥ 8) and those exposed to ≥ 50 mg/day of spironolactone. These convergent findings across rodent and human studies demonstrate that spironolactone reduces alcohol use and support the hypothesis that this medication may be further studied as a novel pharmacotherapy for AUD.

Perspectives on the pharmacological management of alcohol use disorder: Are the approved medications effective?

INTRODUCTION

In the last decades, many medications have been tested for the treatment of Alcohol Use Disorder (AUD). Among them, disulfiram, acamprosate, naltrexone, nalmefene, sodium oxybate and baclofen have been approved in different countries, with different specific indications. Topiramate is not approved for the treatment of AUD, however, it is suggested as a therapeutic option by the American Psychiatric Association for patients who do not tolerate or respond to approved therapies.

AREAS COVERED

In this narrative review we have analyzed the main studies available in literature, investigating the efficacy and safety of these medications, distinguishing whether they were oriented towards abstinence or not. Randomized controlled studies, analyzing larger populations for longer periods were the main focus of our analysis.

CONCLUSIONS

The medications currently available for the treatment of AUD are quite effective, yet further progress can still be achieved through the personalized strategies. Also, these medications are still markedly underutilized in clinical practice and many patients do not have access to specialized treatment.

Effectiveness of spironolactone dispensation in reducing weekly alcohol use: a retrospective high-dimensional propensity score-matched cohort study

There is a need to increase the armamentarium of pharmacotherapies for alcohol use disorder (AUD). Recent research suggests that mineralocorticoid receptor (MR) antagonism via spironolactone may represent a novel pharmacological treatment for AUD. We conducted a pharmacoepidemiologic retrospective cohort study (June 1, 2014 to May 31, 2018) to examine whether spironolactone dispensation (≥90 continuous days), for any indication, is associated with changes in weekly alcohol use about 6 months later. We compared 523 spironolactone-treated adults and 2305 untreated adults, matched on high-dimensional propensity scores created from a set of predefined (sociodemographic and health characteristics, diagnoses, and service utilization) and empirical electronic health record-derived covariates. The sample was 57% female and 27% non-White with a mean age of 59.2 years (SD = 19.3). Treated patients reduced their weekly alcohol use by 3.50 drinks (95% CI = -4.22, -2.79), while untreated patients reduced by 2.74 drinks (95% CI = -3.22, -2.26), yielding a significant difference of 0.76 fewer drinks (95% CI = -1.43, -0.11). Among those who drank >7 drinks/week at baseline, treated patients, compared to untreated patients, reported a greater reduction in weekly alcohol use by 4.18 drinks (95% CI = -5.38, -2.97), while there was no significant difference among those who drank less. There was a significant dose-response relationship between spironolactone dosage and change in drinks/week. Pending additional evidence on its safety and efficacy in individuals with AUD, spironolactone (and MR blockade, at large) may hold promise as a pharmacotherapy for AUD.

Central amygdala mineralocorticoid receptors modulate alcohol self-administration

The mineralocorticoid receptor (MR) is an emerging target in the field of alcohol research. The MR is a steroid receptor in the same family as the glucocorticoid receptor, with which it shares the ligand corticosterone in addition to the MR selective ligand aldosterone. Recent studies have shown correlations between central amygdala (CeA) MR expression and alcohol drinking in rats and macaques, as well as correlations between aldosterone and alcohol craving in individuals with alcohol use disorder (AUD). Additionally, our previous work demonstrated that systemic treatment with the MR antagonist spironolactone reduced alcohol self-administration and response persistence in both male and female rats. This study examined if reductions in self-administration following MR antagonist treatment were related to dysregulation of MR-mediated corticosterone negative feedback. Female rats treated with spironolactone (50 mg/kg; IP) showed increased plasma corticosterone following self-administration, which correlated with reduced alcohol self-administration. Next, local microinjection of the MR-selective antagonist eplerenone was used to identify the brain-regional locus of MR action on alcohol self-administration. Eplerenone infusion produced dose-dependent reductions in alcohol self-administration in the CeA, but had no effect in the dorsal hippocampus. Finally, to assay the functional role of CeA MR expression in alcohol self-administration, CeA MR was knocked down by antisense oligonucleotide (ASO) infusion prior to alcohol self-administration. Rats showed a transient reduction in alcohol self-administration 1 day after ASO infusion. Together these studies demonstrate a functional role of CeA MR in modulating alcohol self-administration and make a case for studying MR antagonists as a novel treatment for AUD.

Mifepristone Decreases Chronic Voluntary Ethanol Consumption in Rhesus Macaques

The efficacy of short-term treatment with mifepristone (MIFE), a high-affinity, nonselective glucocorticoid receptor antagonist, to reduce ethanol drinking was tested in a rhesus macaque model. Stable individual daily ethanol intakes were established, ranging from 1.6 to 4.0 g/kg per day (n = 9 monkeys). After establishment of chronic ethanol intake, a MIFE dosing regimen that modeled a study of rodent drinking and human alcohol craving was evaluated. Three doses of MIFE (17, 30, and 56 mg/kg per day) were each administered for four consecutive days. Both 30 and 56 mg/kg decreased ethanol intake compared with baseline drinking levels without a change in water intake. The dose of 56 mg/kg per day of MIFE produced the largest reduction in ethanol self-administration, with the average intake at 57% of baseline intakes. Cortisol was elevated during MIFE dosing, and a mediation analysis revealed that the effect on ethanol drinking was fully mediated through cortisol. During a forced abstinence phase, access to 1.5 g/kg ethanol resulted in relapse in all drinkers and was not altered by treatment with 56 mg/kg MIFE. Overall, these results show that during active drinking MIFE is efficacious in reducing heavy alcohol intake in a monkey model, an effect that was related to MIFE-induced increase in cortisol. However, MIFE treatment did not eliminate ethanol drinking. Further, cessation of MIFE treatment resulted in a rapid return to baseline intakes, and MIFE was not effective in preventing a relapse during early abstinence. SIGNIFICANCE STATEMENT: Mifepristone reliably decreases average daily ethanol self-administration in a nonhuman primate model. This effect was mediated by cortisol, was most effective during open-access conditions, and did not prevent or reduce relapse drinking.

Intravenous administration of ghrelin increases serum cortisol and aldosterone concentrations in heavy-drinking alcohol-dependent individuals: Results from a double-blind, placebo-controlled human laboratory study

Increasing evidence supports the role of appetite-regulating hormones, including ghrelin, in alcohol use disorder (AUD). Effects of ghrelin administration on cortisol and aldosterone, two hormones known to influence the development and maintenance of AUD, have been observed in ghrelin-exposed tissues or cells, as well as rodents and healthy volunteers, however whether these effects replicate in individuals with AUD is unknown. Here, we tested the hypothesis that intravenous administration of ghrelin leads to increase in endogenous serum cortisol and aldosterone concentrations in alcohol-dependent, heavy drinking individuals, and that these changes may predict ghrelin-induced alcohol craving. This was a double-blind, placebo-controlled human laboratory study in non-treatment-seeking, heavy-drinking, alcohol-dependent individuals randomized to receive either placebo, 1 mcg/kg or 3 mcg/kg of intravenous ghrelin. Then, participants underwent a cue-reactivity procedure in a bar-like setting, which included exposure to both neutral (juice) and alcohol cues. Repeated blood samples were collected and used to measure endogenous cortisol and aldosterone serum concentrations, in response to exogenous ghrelin administration. Furthermore, cortisol and aldosterone serum concentrations were used to develop a model to predict the effect of exogenous ghrelin administration on alcohol craving. Intravenous ghrelin administration increased endogenous cortisol and aldosterone serum concentrations. While the effects on cortisol were greater than those on aldosterone, only the ghrelin-induced changes in aldosterone serum concentrations predicted craving. These findings provide initial evidence of ghrelin effects on glucocorticoids and mineralocorticoids in individuals with AUD, thereby providing additional information on the potential mechanisms by which the ghrelin system may play a role in alcohol craving and seeking in AUD.

Baclofen in the Treatment of Patients With Alcohol Use Disorder and Other Mental Health Disorders

A limited number of medications are approved to treat Alcohol Use Disorder (AUD). Furthermore, the magnitude of their therapeutic effect is relatively modest, suggesting the potential for subtypes of patients who respond to a specific medication. The use of these medications is also limited in clinical practice by a series of contraindications such as medical comorbidities and/or concurrent use of other medications. In recent years, animal and human studies have been conducted to evaluate the efficacy of baclofen, a GABAB receptor agonist approved for clinical use as a muscle relaxant, in the treatment of AUD. However, these studies have yielded contrasting results. Despite this discrepancy, baclofen is often used off-label to treat AUD, especially in some European countries and Australia. Recently, several factors have been considered to try to shed light on the potential reasons and mechanisms underlying the inconsistent results obtained until now. The presence of a psychiatric comorbidity may be amongst the abovementioned factors playing a role in explaining different responses to baclofen treatment in terms of alcohol drinking outcomes. Therefore, the aim here was to conduct a narrative review of the scientific literature related to the use of baclofen in AUD, both in patients with and without concomitant psychiatric disorders. All clinical studies (randomized and controlled, open-label, retrospective, human laboratory studies, and case reports) were analyzed and discussed, bearing in mind other potential factors that may have influenced baclofen response, including dose administered, severity of AUD, use of other psychosocial therapies, and the presence of physical disorders. This review indicates that the most frequent psychiatric comorbidities in patients affected by AUD undergoing baclofen treatment are anxiety and mood disorders. Unfortunately, no definitive conclusions can be drawn due to the lack of specific analyses on whether baclofen efficacy is different in AUD patients with comorbid psychiatric disorders vs. those without. Therefore, it will be critical that psychiatric comorbidities are considered in the planning of future studies and in the analysis of the data, with the ultimate goal of understanding whether subtypes of AUD patients may respond best to baclofen.

The mineralocorticoid receptor antagonist spironolactone reduces alcohol self-administration in female and male rats

Cortisol/corticosterone and the hypothalamic-pituitary-adrenal (HPA) axis serve an important role in modulating alcohol drinking behaviors. To date most alcohol research has focused on the functional involvement of corticosterone and the glucocorticoid receptor (GR), the primary receptor for corticosterone. Recent studies have indicated that the related mineralocorticoid receptor (MR), which binds both corticosterone and aldosterone, may also play a role in alcohol drinking. Therefore, the purpose of the present study was to test the functional role of MR signaling in alcohol self-administration via pharmacological antagonism of the MR with spironolactone. Male and female Long-Evans rats were trained to self-administer a sweetened alcohol solution (15% (v/v) alcohol +2% (w/v) sucrose). The effects of spironolactone (0, 10, 25, 50 mg/kg; IP) were tested on alcohol self-administration and under "probe extinction" conditions to measure the persistence of responding in the absence of the alcohol reinforcer. Parallel experiments in sucrose self-administration trained rats were used to confirm the specificity of spironolactone effects to an alcohol reinforcer. In female rats spironolactone (50 mg/kg) reduced alcohol self-administration and persistence of alcohol responding. In male rats spironolactone (25 and 50 mg/kg) reduced alcohol self-administration, but not persistence of alcohol responding. Spironolactone reduced sucrose intake in female rats only, and locomotion in male and female rats during sucrose self-administration. There was no effect of spironolactone on persistence of sucrose responding. These studies add to growing evidence that the MR is involved in alcohol drinking, while underscoring the importance of studying both male and female animals.

A relationship between the aldosterone-mineralocorticoid receptor pathway and alcohol drinking: preliminary translational findings across rats, monkeys and humans

Aldosterone regulates electrolyte and fluid homeostasis through binding to the mineralocorticoid receptors (MRs). Previous work provides evidence for a role of aldosterone in alcohol use disorders (AUDs). We tested the hypothesis that high functional activity of the mineralocorticoid endocrine pathway contributes to vulnerability for AUDs. In Study 1, we investigated the relationship between plasma aldosterone levels, ethanol self-administration and the expression of CYP11B2 and MR (NR3C2) genes in the prefrontal cortex area (PFC) and central nucleus of the amygdala (CeA) in monkeys. Aldosterone significantly increased after 6- and 12-month ethanol self-administration. NR3C2 expression in the CeA was negatively correlated to average ethanol intake during the 12 months. In Study 2, we measured Nr3c2 mRNA levels in the PFC and CeA of dependent and nondependent rats and the correlates with ethanol drinking during acute withdrawal. Low Nr3c2 expression levels in the CeA were significantly associated with increased anxiety-like behavior and compulsive-like drinking in dependent rats. In Study 3, the relationship between plasma aldosterone levels, alcohol drinking and craving was investigated in alcohol-dependent patients. Non-abstinent patients had significantly higher aldosterone levels than abstinent patients. Aldosterone levels positively correlated with the number of drinks consumed, craving and anxiety scores. These findings support a relationship between ethanol drinking and the aldosterone/MR pathway in three different species.

The Epigenetic Regulation of GATA4-Dependent Brain Natriuretic Peptide Expression during Alcohol Withdrawal

OBJECTIVE

Natriuretic peptides participate in the collection of metabolic effects during alcohol withdrawal. Having witnessed modulation of other natriuretic peptides in alcohol-dependent patients during alcohol withdrawal, we were interested in the relation of brain natriuretic peptide (BNP) methylation with protein expression and craving in this longitudinal study.

METHODS

Ninety-nine male patients were compared to 101 healthy controls concerning epigenetic regulation and protein expression during detoxification treatment.

RESULTS

With BNP expression being GATA4 dependent, we observed a correlation of GATA4 binding site methylation and protein expression. BNP serum levels and Obsessive Compulsive Drinking Scale scores are significantly decreased during withdrawal. Focusing on the two CpGs that are between GATA transcription factor binding sites, statistical analysis revealed a reversely proportional methylation pattern, significantly increasing with ongoing detoxification and thereby supporting the observed serum level changes.

CONCLUSION

Without the functional knowledge about regulation of BNP expression via the GATA transcription factor, it would have been easy to take the mean results of the global CpG data and propose a direct relationship between methylation and expression. Thus, these findings are a voice for functionally and mechanistically approved results. There was no causal relationship between protein expression levels and epigenetic changes. Further research is needed which includes protein expression and other approaches.

Higher pretreatment blood pressure is associated with greater alcohol drinking reduction in alcohol-dependent individuals treated with doxazosin

BACKGROUND

Preclinical and clinical research suggest that the α₁ receptor antagonist prazosin reduces alcohol consumption. Furthermore, clinical studies indicate a role for prazosin in treating Post-Traumatic Stress Disorder (PTSD) symptoms and a recent trial suggested that pre-treatment blood pressure (BP) predicts therapeutic response for prazosin in PTSD patients. Whether pre-treatment BP may predict response to α₁ blockers in alcohol-dependent (AD) patients is unknown. We previously reported a randomized controlled trial (RCT) where doxazosin, an α₁ receptor antagonist with a more favorable pharmacokinetic profile than prazosin, reduced drinks per week (DPW) and heavy drinking days (HDD) in AD patients with a high family history density of alcoholism. In this study, we tested pre-treatment BP as another potentially valuable clinical moderator of doxazosin's response on alcohol consumption.

METHODS

This was a double-blind placebo-controlled RCT testing doxazosin up to 16mg/day in AD treatment-seeking patients (N=41). The hypothesized moderator effect of baseline standing systolic and diastolic BP on DPW and HDD was tested.

RESULTS

With pre-treatment standing diastolic BP as a moderator, there were significant BP x medication interactions for both DPW [**p=0.009, d=0.80] and HDD [*p=0.018, d=1.11]. Post-hoc analyses indicated significant doxazosin effects in patients with higher standing BP in reducing both DPW and HDD.

CONCLUSION

These findings suggest that higher standing diastolic BP at baseline (pre-treatment) may represent a predictor of doxazosin's response on alcohol consumption in AD patients. These results further elucidate the possible efficacy and mechanisms of action of α₁ receptor antagonism in AD individuals.

Treatment of alcohol use disorders in patients with alcoholic liver disease

Alcohol use disorders (AUDs) is one of the leading causes of disease and disability in almost all European countries. Among the alcohol-related diseases, alcoholic liver disease (ALD) is the most common. At present, alcohol is the most frequent cause of liver cirrhosis in the Western world. The cornerstone of treatment for ALD is achieving total alcohol abstinence and preventing relapse; medical and surgical treatments for ALD are limited when drinking continues. This narrative review summarizes current treatments for AUDs with a particular emphasis to the treatment of AUDs in patients with ALD. Medical management, psychosocial and pharmacological interventions are analyzed, underlying limits and options in AUD patients. Finally, this review discusses the most appropriate setting for the management of AUD patients with advanced liver disease as well as the indications for liver transplantation in AUD patients.

A human laboratory pilot study with baclofen in alcoholic individuals

Preclinical and clinical studies show that the GABA(B) receptor agonist baclofen may represent a pharmacotherapy for alcohol dependence (AD). However, the mechanisms by which baclofen affects drinking are not well characterized; thus this pilot study investigated possible baclofen's biobehavioral mechanisms. The design was a double-blind controlled randomized human laboratory pilot study. Fourteen non-treatment seeking alcohol-dependent heavy drinking subjects received either baclofen 10mg t.i.d. or an active placebo (cyproheptadine 2mg t.i.d., to control for sedation) for a 7-day period. At day 8, participants performed an alcohol cue-reactivity (CR) followed by an alcohol self-administration (ASA). Additionally, we explored possible moderators that might guide future larger studies, i.e. anxiety, family history and onset of alcoholism, and D4 dopamine receptor (DRD4) and 5-HTTLPR polymorphisms. The main results were a significant effect of baclofen for increasing stimulation (p=.001) and sedation (p<.01). Furthermore, when drinking during the ASA and the 2 days before was analyzed as a composite variable, there was a significant effect of baclofen to reduce alcohol consumption (p<.01). As for the exploratory analyses, baclofen's effects to increase alcohol sedation and to reduce alcohol consumption were limited to those individuals with DRD4 ≥7 repeats (DRD4L). Yet, baclofen's effects on alcohol consumption were also moderated by 5-HTTLPR LL genotype. In conclusion, baclofen's ability to reduce alcohol drinking may be related to its effects on the biphasic effects of alcohol, but larger studies are needed to confirm these preliminary findings.

Baclofen promotes alcohol abstinence in alcohol dependent cirrhotic patients with hepatitis C virus (HCV) infection

Hepatitis C virus (HCV) and alcoholic liver disease (ALD), either alone or in combination, count for more than two thirds of all liver diseases in the Western world. There is no safe level of drinking in HCV-infected patients and the most effective goal for these patients is total abstinence. Baclofen, a GABA(B) receptor agonist, represents a promising pharmacotherapy for alcohol dependence (AD). Previously, we performed a randomized clinical trial (RCT), which demonstrated the safety and efficacy of baclofen in patients affected by AD and cirrhosis. The goal of this post-hoc analysis was to explore baclofen's effect in a subgroup of alcohol-dependent HCV-infected cirrhotic patients. Any patient with HCV infection was selected for this analysis. Among the 84 subjects randomized in the main trial, 24 alcohol-dependent cirrhotic patients had a HCV infection; 12 received baclofen 10mg t.i.d. and 12 received placebo for 12-weeks. With respect to the placebo group (3/12, 25.0%), a significantly higher number of patients who achieved and maintained total alcohol abstinence was found in the baclofen group (10/12, 83.3%; p=0.0123). Furthermore, in the baclofen group, compared to placebo, there was a significantly higher increase in albumin values from baseline (p=0.0132) and a trend toward a significant reduction in INR levels from baseline (p=0.0716). In conclusion, baclofen was safe and significantly more effective than placebo in promoting alcohol abstinence, and improving some Liver Function Tests (LFTs) (i.e. albumin, INR) in alcohol-dependent HCV-infected cirrhotic patients. Baclofen may represent a clinically relevant alcohol pharmacotherapy for these patients.

Novel therapeutic strategies for alcohol and drug addiction: focus on GABA, ion channels and transcranial magnetic stimulation

Drug addiction represents a major social problem where addicts and alcoholics continue to seek and take drugs despite adverse social, personal, emotional, and legal consequences. A number of pharmacological compounds have been tested in human addicts with the goal of reducing the level or frequency of intake, but these pharmacotherapies have often been of only moderate efficacy or act in a sub-population of humans. Thus, there is a tremendous need for new therapeutic interventions to treat addiction. Here, we review recent interesting studies focusing on gamma-aminobutyric acid receptors, voltage-gated ion channels, and transcranial magnetic stimulation. Some of these treatments show considerable promise to reduce addictive behaviors, or the early clinical studies or pre-clinical rationale suggest that a promising avenue could be developed. Thus, it is likely that within a decade or so, we could have important new and effective treatments to achieve the goal of reducing the burden of human addiction and alcoholism.

Emerging drugs to treat alcoholism

IMPORTANCE OF THE FIELD

Alcoholism is a widespread disorder with substantial mortality and negative treatment outcomes. To date, few medications have been found to reduce relapse rates or drinking in alcohol-dependent patients.

AREAS COVERED IN THIS REVIEW

This review focuses on drugs that have been clinically tested for the treatment of alcohol dependence in clinical trials, pilot trials or which are considered to have a clinical perspective. For this purpose, a detailed Medline search was conducted on this issue. Although the neurochemical basis of alcoholism and the neuronal circuitry mediating its psychotropic effects have been explored in great detail in recent years, few drugs have emerged for the treatment of alcohol dependence, also because pharmaceutical companies have only a limited interest in this area of research. Acamprosate and the opioid antagonist naltrexone have been found to be effective, although data are mixed. A depot formula of naltrexone and the alternate opioid antagonist nalmefene have been studied in clinical trials and will presumably be introduced in the markets soon. Other emerging drugs are topiramate, novel acetaldehyde dehydrogenase (ALDH) inhibitors, baclofen, a combination therapy of gababentin and flumazenil and drugs targeting the cortitropin-releasing factor/neuropeptide Y mediated stress axis.

WHAT THE READER WILL GAIN

Insights on the neurochemical basis of alcohol dependence and possible targets of medications.

TAKE HOME MESSAGE

Acamprosate, naltrexone and the ALDH inhibitor disulfiram are proven medications for the treatment of alcohol dependence with modest efficacy. Novel alternate medications, a depot formulation of the opioid antagonist naltrexone and another oral opioid antagonist, nalmefene, are available now with good evidence for clinical efficacy. Novel ALDH inhibitors, antiepileptic drugs such as topiramate and drugs targeting the stress axis are currently among the most promising emerging drugs.

Psychosocial findings in alcohol-dependent patients before and after three months of total alcohol abstinence

Alcohol use disorders (AUDs) may be associated with several psychological and affective disorders. It is controversial, however, if these symptoms are a cause or rather a consequence of alcohol dependence. There are few data testing simultaneously psychosocial and affective disorders before and after a period of alcohol abstinence. The aim of this study was to perform multiple psychometric evaluations in alcohol-dependent patients before and after 12 weeks of abstinence. Twenty-five alcohol-dependent patients were included in the study. The following psychometric tests were administered at baseline (T0) and after 12 weeks (T1): addiction severity index (ASI), brief psychiatric rating scale (BPRS), social behavior scale (SBS), Sheehan disability scale (DISS), aggression questionnaire (AQ). At T1, 16 (64%) patients were abstinent, 5 (20%) patients dropped out and 4 (16%) patients relapsed. Compared to T0, patients totally abstinent at T1 showed a significant reduction of the scores related to BPRS, BPRS-E and its subscales (except BPRS 5), ASI 1, ASI 2, ASI 3, ASI 6, ASI 7, BSM, AQ, DISS 1, DISS 2, DISS 3 (p < 0.05). No significant changes in ASI 4, ASI 5, DISS 4, and DISS 5, BPRS 5 scores were found at T1 compared to T0. The present study indicates that total alcohol abstinence improves psychometric features, such as alcohol addiction severity, psychiatric rating, social behavior, aggressiveness, and disability. Larger controlled studies are needed to confirm these findings.

Sleep disturbance as a universal risk factor for relapse in addictions to psychoactive substances

Relapse to uncontrolled use of a psychoactive substance is arguably the single most defining characteristic of an addiction. Relapse following addiction treatment is very common with serious consequences to individuals, families, and the public system of care, making predictors of relapse a highly significant area of study. Before the turn of the century, most of the addiction treatment outcome literature focused on psychosocial predictors of relapse. More recently, investigating biological predictors of relapse specifically and treatment outcome broadly has gained momentum. This line of research has linked sleep disturbances to the risk of relapse among persons who are recovering from an alcohol addiction. Given common neurobiological and psychosocial processes in sleep and addictive behaviors, we hypothesize that the link between sleep disturbance and relapse risk observed among alcohol addiction generalizes to all other types of psychoactive substances. This hypothesis has the potential for helping develop more effective and targeted treatment approaches for persons with addiction. As initial support for the hypothesis, this paper reviews evidence on common neurobiological processes among various types of psychoactive substances that suggests sleep is a universal risk factor for relapse. A conceptual framework is also presented to articulate causal mechanisms. The paper concludes with implications for research and practice.

Role of the GABA(B) receptor system in alcoholism and stress: focus on clinical studies and treatment perspectives

Alcoholism and stress share some common neurobiological circuits, including the GABAergic system. In particular, the GABA(B) receptor seems to play an important role. The GABA(B) receptor agonist baclofen has been studied as a treatment for alcohol-dependent subjects. Baclofen administration in alcohol-dependent patients was able to promote abstinence, inducing the remission of withdrawal symptoms, reducing alcohol craving, and reducing alcohol intake. Baclofen also reduced anxiety in alcohol-dependent subjects, probably acting on brain stress circuitry and/or on other neuroendocrine systems. Baclofen also showed excellent safety and tolerability, even in alcohol-dependent patients with advanced liver disease (i.e., cirrhosis). Future studies should investigate which alcoholic subtype may better benefit of the administration of baclofen in the treatment of alcohol dependence.

Effects of naltrexone on cortisol levels in heavy drinkers

The primary objectives of this study were to: (a) examine the neuroendocrine effects of naltrexone vs. placebo by comparing serum cortisol levels; and (b) test the biobehavioral correlates of naltrexone-induced changes in cortisol. Non-treatment seeking heavy drinkers (n=37) completed two intravenous alcohol administrations, one after naltrexone (50 mg) and one after placebo. Cortisol levels were measured at baseline and after alcohol intake (BrAC=0.06 g/dl) on both sessions, as were subjective responses to alcohol. Analyses revealed that naltrexone significantly raised overall cortisol levels compared to placebo. Cortisol levels decreased during alcohol administration and a stronger decrease was observed in the naltrexone condition. Cortisol levels were, in turn, inversely related to some of alcohol's the reinforcing effects (i.e., alcohol 'high,' vigor) and positively associated with some of its unpleasant effects (i.e., sedation and subjective intoxication). These results suggest that naltrexone alters cortisol levels in heavy drinkers and that its effects on subjective responses to alcohol may be related, in part, to naltrexone's ability to activate the HPA-axis.

Is cortisol involved in the alcohol-related fat mass impairment? A longitudinal clinical study

AIMS

Subjects with chronic alcohol abuse can present several metabolic and nutritional alterations. The hypothalamic-pituitary-adrenal (HPA) axis may play a role in these nutritional and metabolic disorders. The goal of this study was to investigate if there is any relationship between HP-hormones and metabolic and nutritional parameters in alcoholic subjects.

METHODS

Sixteen alcoholics were considered before and after 3 months of total alcohol abstinence. HP-related hormones were determined. Nutritional and metabolic parameters were assessed by dual-energy X-ray absorptiometry (DXA) and indirect calorimetry.

RESULTS

At baseline, a significant negative correlation was found between fat mass (FM) and cortisol (r = -0.54, P = 0.03). During abstinence, a significant increase of both body mass index (BMI) (P < 0.0001) and FM (P < 0.0001) was found at 12 weeks compared to baseline. A significant decrease of both plasma cortisol (P = 0.044) and aldosterone (P = 0.023) was found at 12 weeks compared to baseline. At 12 weeks, the significant correlation between cortisol and FM disappeared.

CONCLUSIONS

A higher HPA-axis activation-reflected by higher cortisol levels-was associated with a lower FM in alcoholics. Conversely, during total abstinence a reduced HPA-axis activity can play a role in the parallel nutritional recovery. The present results suggest a role of the HPA axis throughout cortisol both in the etiology of the alcohol-related nutritional alterations and in their recovery after a period of total alcohol abstinence.

Acute interaction of baclofen in combination with alcohol in heavy social drinkers

BACKGROUND

There is growing evidence that gamma-amino butyric acid-B receptor agonists may be effective in the treatment of alcohol abuse or dependence. The primary goal of this study was to determine the safety of baclofen in combination with alcohol consumption in heavy drinkers. In addition, the effects of baclofen alone, and in combination with alcohol, on subjective effects, cognitive performance effects, as well as alcohol craving, were assessed.

METHODS

Eighteen non-treatment-seeking heavy social drinkers (mean of 28 drinks per week), who did not meet the criteria for alcohol dependence participated. All individuals were tested using a double-blind double-dummy design with six 2-day inpatient phases. Baclofen (0, 40, and 80 mg) was administered 2.5 hours before alcohol (1.5 g/l body water or approximately 0.75 g/kg) or placebo beverages, given in 4 divided doses every 20 minutes.

RESULTS

Baclofen, either alone or in combination with alcohol, produced only modest increases in heart rate and blood pressure and no adverse effects were reported. Baclofen did not increase positive subjective effects (e.g., Stimulant effects, Drug Liking) but did increase sedation and impair performance. Even though both baclofen and alcohol impaired performance, for the most part performance was not impaired to a greater extent when baclofen was combined with alcohol. Among this population of nondependent drinkers, baclofen did not alter alcohol craving or alcohol-induced positive subjective effects.

CONCLUSIONS

Baclofen alone has minimal abuse liability in heavy social drinkers, and baclofen is relatively well tolerated and safe when given in combination with intoxicating doses of alcohol.