Ghrelin is a peptide, mainly produced in the stomach, but also found in small amounts in the brain. It is known to affect food intake by increasing feelings of hunger and the urge to eat. A new study by Jörgen Engel, professor of pharmacology at the Sahlgrenska Academy, University of Gothenburg has examined ghrelin’s role in addictive behaviours. Findings indicate that variations in the genes producing ghrelin and its receptor are more common in individuals considered to be heavy drinkers.
For this research, scientists recruited 417 Spanish individuals from the general population (n=279) as well as heavy drinkers (n=138) admitted to a hospital for treatment. The study sample comprised of abstainers, moderate and heavy alcohol drinkers was then examined for single nucleotide polymorphisms (SNPs) in the pro-ghrelin and growth hormone secretagogue receptors (GHS-R1A) gene.
Findings showed that SNP rs2232165 of the GHS-R1A gene was associated with heavy alcohol consumption. SNP rs2948694 of the same gene as well as haplotypes of both the pro-ghrelin and the GHS-R1A genes were associated with an increased body mass in individuals consuming heavy amounts of alcohol.
“Not only are these specific variations in the genes producing ghrelin and its receptor more common in heavy alcohol-using individuals,” said Engel, “these variations also seem to have an influence on the body weight of these heavy drinking individuals, as we found an association with an increased body weight in these patients. In other words, if you are a carrier of these genetic variants in the ghrelin or ghrelin receptor gene, you are more susceptible to having multiple addictive behaviours such as alcohol dependence and overeating.”
“Our findings may help to explain the comorbidity of different addictive behaviours such as alcohol addiction and compulsive overeating,” said Engel, “providing clues to the genetic basis for the development of these kind of disorders. Ghrelin and its receptor could thus be targets for the development of new drugs for alcohol dependence or a subtype of alcohol-dependent individuals with eating disorders such as compulsive overeating.”
Source: Results will be published in the December issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.