The association of plasma acyl ghrelin level with alcohol craving in early abstinent alcohol dependent patients

Alcohol use disorder research in India: An update

Background

Despite alcohol use being a risk factor for numerous health-related conditions and alcohol use disorder (AUD) recognized as a disease, there was limited research in India until 2010. This narrative review aims to evaluate AUD-related research in India from 2010 to July 2023.

Methods

A PubMed search used key terms for AUD in India after 2010. Indian and international journals with regional significance that publish alcohol-related research were searched by each author individually. These were then collated, and duplicates were removed. In addition, we also conducted a gray literature search on focused areas related to AUD.

Results

The alcohol-related research in India after 2010 focused on diverse areas associated with alcohol use. Some areas of research have received more attention than others. Two major epidemiological surveys conducted in the past decade reveal that around 5% have a problematic alcohol use pattern. Factors associated with alcohol use, like genetic, neurobiological, psychological, and sociocultural, were studied. The studies focused on the clinical profile of AUD, including their correlates, such as craving, withdrawal, alcohol-related harm, and comorbid psychiatric and medical illnesses. During this period, minimal research was conducted to understand AUD's laboratory biomarkers, course, and prognosis. While there was a focus on generating evidence for different psychological interventions for alcohol dependence in management-related research, pharmacological studies centered on anticraving agents like baclofen. Research on noninvasive brain stimulation, such as rTMS, has shown preliminary usefulness in treating alcohol dependence. Very little research has been conducted regarding alcohol policy.

Conclusion

In the past decade, Indian research on alcohol has focused on diverse areas. Epidemiological and psychological management-related research received maximum attention. Considering the magnitude of the alcohol-related burden, it is essential to prioritize research to other less studied areas like pharmacological management of alcohol dependence and alcohol policy.

Ghrelin Predicts Stimulant and Sedative Effects of Alcohol in Heavy Drinkers

AIM

The aim of this study was to examine the relationship between ghrelin levels and the subjective effects of alcohol in heavy drinkers, and to compare them to healthy controls.

METHODS

Ghrelin levels were collected as part of two laboratory studies. Both groups received either IV infusion of saline or high dose of alcohol (100 mg%). In the study of heavy drinkers, ghrelin was gathered on all subjects, but data was analyzed only for participants who received placebo (N=12). Healthy controls (N=20) came from another study that collected data on family history. Ghrelin levels and measures of alcohol effects (BAES, VAS, NDS, YCS [see manuscript for details]) were collected at 4 timepoints: baseline, before infusion, during infusion and after infusion.

RESULTS

IV alcohol significantly reduced ghrelin levels and higher fasting ghrelin levels were associated with more intense subjective alcohol effects. There were no differences in fasting ghrelin levels or subjective effects between heavy drinkers and controls. However, while both groups showed similar decline in ghrelin levels following alcohol infusion, on the placebo day, ghrelin levels in the healthy subjects increased significantly and exponentially over time while for the heavy drinkers ghrelin levels remained flat.

CONCLUSIONS

Our findings support the role of ghrelin in reward mechanisms for alcohol. Contrary to others, we found no differences in fasting ghrelin levels or subjective experiences of alcohol between heavy drinkers and healthy controls. However, the group differences on the IV placebo day may be a possible indication of ghrelin abnormalities in heavy drinkers.

Role of the ghrelin system in alcohol use disorder and alcohol-associated liver disease: A narrative review

Unhealthy alcohol consumption is a global health problem. Adverse individual, public health, and socioeconomic consequences are attributable to harmful alcohol use. Epidemiological studies have shown that alcohol use disorder (AUD) and alcohol-associated liver disease (ALD) are the top two pathologies among alcohol-related diseases. Consistent with the major role that the liver plays in alcohol metabolism, uncontrolled drinking may cause significant damage to the liver. This damage is initiated by excessive fat accumulation in the liver, which can further progress to advanced liver disease. The only effective therapeutic strategies currently available for ALD are alcohol abstinence or liver transplantation. Any molecule with dual-pronged effects at the central and peripheral organs controlling addictive behaviors and associated metabolic pathways are a potentially important therapeutic target for treating AUD and ALD. Ghrelin, a hormone primarily derived from the stomach, has such properties, and regulates both behavioral and metabolic functions. In this review, we highlight recent advances in understanding the peripheral and central functions of the ghrelin system and its role in AUD and ALD pathogenesis. We first discuss the correlation between blood ghrelin concentrations and alcohol use or abstinence. Next, we discuss the role of ghrelin in alcohol-seeking behaviors and finally its role in the development of fatty liver by metabolic regulations and organ crosstalk. We propose that a better understanding of the ghrelin system could open an innovative avenue for improved treatments for AUD and associated medical consequences, including ALD.

G-CuP: the effect of a forced oral glucose intake on alcohol craving and mesolimbic cue reactivity in alcohol dependence-study protocol of a randomized, double-blind, placebo-controlled crossover study

BACKGROUND

Multiple studies indicate that a lower plasma level of the acetylated form of the appetite-regulating hormone ghrelin and higher plasma levels of insulin lead to a reduction in subjective alcohol craving and a reduced mesolimbic cue reactivity in functional magnetic resonance imaging (fMRI) when being exposed to alcohol-associated stimuli. The ghrelin level can physiologically be reduced by the induction of stomach distension and the ingestion of glucose or lipids.

METHODS

A total of 108 alcohol-dependent patients aged between 18 and 65 years are examined in the randomized, double-blind, placebo-controlled crossover study. After collecting demographic and psychometric data, participants take part in an alcohol exposure session. Afterwards, the participants go through the intervention condition (oral glucose intake) and the control condition (placebo intake) in a randomized order on two examination days. Blood samples are taken repeatedly (every 10 min) during the study course on both measuring days to determine changes in acetylated and total ghrelin and insulin plasma levels. In parallel, subjective alcohol craving after the glucose or placebo intake as the primary outcome is assessed using the Alcohol Urge Questionnaire (AUQ) and a visual analog scale (VAS). To examine the mesolimbic cue reactivity as the secondary outcome, a fMRI measurement is conducted while being exposed to alcohol-related stimuli. Appropriate statistical analysis will be used for the evaluation of the outcomes.

DISCUSSION

If successful, the results of this study could offer alcohol-dependent patients a new potential option for acute short-term reduction of alcohol craving and thus prevent relapses and prolong periods of abstinence in the long term.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00022419 (UTN: U1111-1278-9428). Retrospectively registered on September 15, 2020.

An Overview of Appetite-Regulatory Peptides in Addiction Processes; From Bench to Bed Side

There is a substantial need for new pharmacological treatments of addiction, and appetite-regulatory peptides are implied as possible candidates. Appetite regulation is complex and involves anorexigenic hormones such as glucagon-like peptide-1 (GLP-1) and amylin, and orexigenic peptides like ghrelin and all are well-known for their effects on feeding behaviors. This overview will summarize more recent physiological aspects of these peptides, demonstrating that they modulate various aspects of addiction processes. Findings from preclinical, genetic, and experimental clinical studies exploring the association between appetite-regulatory peptides and the acute or chronic effects of addictive drugs will be introduced. Short or long-acting GLP-1 receptor agonists independently attenuate the acute rewarding properties of addictive drugs or reduce the chronic aspects of drugs. Genetic variation of the GLP-1 system is associated with alcohol use disorder. Also, the amylin pathway modulates the acute and chronic behavioral responses to addictive drugs. Ghrelin has been shown to activate reward-related behaviors. Moreover, ghrelin enhances, whereas pharmacological or genetic suppression of the ghrelin receptor attenuates the responses to various addictive drugs. Genetic studies and experimental clinical studies further support the associations between ghrelin and addiction processes. Further studies should explore the mechanisms modulating the ability of appetite-regulatory peptides to reduce addiction, and the effects of combination therapies or different diets on substance use are warranted. In summary, these studies provide evidence that appetite-regulatory peptides modulate reward and addiction processes, and deserve to be investigated as potential treatment target for addiction.

A population-based investigation of the association between alcohol intake and serum total ghrelin concentrations among cigarette-smoking, non-alcohol-dependent male individuals

BACKGROUND

Ghrelin plays significant roles in regulating appetite, food intake, and metabolism. Furthermore, the ghrelin system is increasingly being studied in relation to alcohol seeking behaviors. To this end, it is important to understand the possible effects of alcohol intake on the ghrelin system. The aim of the present study was to investigate the association between alcohol drinking and circulating ghrelin levels in a large sample of cigarette-smoking, non-alcohol-dependent male individuals.

METHODS

We utilized data from two nested case-control studies (study A, n = 807; study B, n = 976) based within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) trial. Data on alcohol consumption (grams of pure alcohol consumed per day) were obtained via a food frequency questionnaire. Blood samples were also collected (after 12 h of fasting), and serum concentrations of total ghrelin were measured by radioimmunoassay.

RESULTS

Dichotomous comparison between alcohol drinkers (>0 g/day of alcohol intake) and non-drinkers (0 g/day of alcohol intake) found higher total ghrelin levels among individuals who drank alcohol than those who did not, with statistically significant results in study A [F (1, 798) = 4.32, P = 0.03] and less robust results in study B [F (1, 966) = 2.62, P = 0.10], controlling for a list of factors that may influence ghrelin levels and/or differ between drinkers and non-drinkers. Bivariate correlational analysis among drinkers found no association between the quantity of daily alcohol intake and blood total ghrelin concentrations.

CONCLUSION

These results indicate elevated ghrelin levels among alcohol drinkers and provide additional/relevant information on the complex interaction between alcohol use and the ghrelin system.