Vital Brain Protein Central Factor in Transition From Moderate to Problem Drinking
In the October 24 online edition of the journal Molecular Psychiatry, members of the department of neurology at UC San Francisco discussed a research program they sponsored that delved into the brain chemistry behind binge drinking and alcoholism. Specifically, they were investigating the relationship between shortages of a protein called BDNF (brain-derived neurotrophic factor) and a person’s escalating desire to consume alcohol.
Medical science’s view of drug addiction and alcoholism has evolved considerably over the past three decades. Addiction is now viewed as a brain disease with strong biological determinants. This does not mean the psychological aspects of the disease are being neglected. But as perspective widens, traditional talk therapy is being supplemented more and more by medicines that can provide chemically appropriate support to the sincere attempts of addicts to put their substance abuse problems behind them.
Developing good medicines to counteract addiction requires good biological knowledge, especially in the fields of neurology and genetics. Fortunately, technological advancement in the medical sciences is opening new frontiers for intrepid scientific explorers in search of information and comprehension, particularly in the deep sub-microscopic realms where DNA is king.
BDNF May Be a Binge Drinker’s Best Friend
BDNF is a vitally important nutrient that acts like a fertilizer for the brain. It invigorates the health of the brain’s neurons by amplifying the electrical signals that interconnect them, even as it promotes the growth of new neurons to replace those that die off. Those who suffer from deficiencies of BDNF are prone to bouts of depression and even suicide, and physical exercise is often recommended as a way to stimulate its production.
The factors that reduce the density of BDNF in the human brain are not completely understood. But evidence suggests regular, heavy drinking is one possible cause. Interestingly, moderate alcohol consumption is known to increase BDNF levels, and the UCSF researchers were curious to learn more about what role developing BDNF deficiencies might play in facilitating the transition from moderate alcohol consumption to full-fledged binge drinking. In order to obtain the relevant data, they performed chemical analyses on the brains of mice that were fed alcohol at varying levels to see if a correlation could be found between the presence of BDNF and an uncontrolled desire to drink. And sure enough, it was discovered that mice that consumed large amounts of alcohol did indeed experience a decline in the concentration of BDNF in their brains, whereas mice that stayed on moderate alcohol diets were able to maintain much higher BDNF levels.
But the most important breakthrough achieved by the UCSF research team was their discovery that BDNF levels were going down in response to the activities of a type of genetic material called microRNA. As a messenger for DNA, microRNA is known to play a major role in gene expression, and in the brains of the binge-drinking mice there was an abundance of a strain of microRNA labeled as 30a-5p. This seemed suspicious, and the UCSF researchers found that by manipulating levels of this molecule they could moderate their subjects’ interest in alcohol. When 30a-5p was present in greater amounts, BDNF concentrations dropped and vice versa, and the desire for alcohol in the mice fluctuated in a synchronous fashion. Binge-drinking mice were in essence “cured” of their desire to drink incessantly, just through the administration of a 30a-5p inhibitor.
Exercise Boosts BDNF
Much more work will have to be done to verify these results and to prove they apply to humans. And even if the physical urge to drink could be influenced by medicines that suppress 30a-5p and/or boost BDNF, the psychological factors that buffer unhealthy drinking habits would still remain and would need to be acknowledged and treated. Another fact worth noting is that exercise has a proven ability to increase the body’s production of BDNF, so it is certainly possible that exercise therapies for recovering alcoholics or binge drinkers could be just as effective as medication in some instances.
But if human studies confirm the findings of this study, it could eventually lead to the creation of therapeutic drugs that would be highly beneficial to many individuals suffering from alcohol-related disorders.