Exercise Gene Boost Tapped as Possible Anti-Depressant

Scientists at Yale University under the lead of Ronald Duman, professor of psychiatry, have found a gene in the brain related to exercise. Through the course of their studies they discovered an enhancement of this particular gene could result in a powerful anti-depressant type of reaction. This discovery could open up new opportunities in the area of anti-depressant drug development.

According to Duman, sixteen percent of the American population suffers from depression. Yet, anti-depressant treatment is only affective for about two thirds of them. Many have to undergo treatment for several months in order to recover from the condition. The costs for these treatments average $83 billion annually.

Scientists have already proven that exercise boosts brain function and mental health. Furthermore, exercise is helpful in cases of brain injury and disease. Unfortunately, scientists have been unable to determine how exercise exactly influences the brain functions. Duman theorizes, "that some neuronal adaptation or plasticity is needed" because traditional drug treatment does not show a quick effect in patients. Rather results are only achieved once drugs have been taken over a longer timeframe.

To obtain a clearer picture of what is going on in the brain during exercise, the researchers at Yale University constructed a custom micro array. With the aid of the micro array, the scientists were able to detect minor variations in gene expression, especially in the hippocampus. The hippocampus is the part of the brain, which has a strong sensitivity to stress hormones. This is also the area, which reacts the strongest to the effects of anti-depressant and depression.

The scientists conducted their studies on mice, which were divided into two groups: a sedentary one and one that was provided with running wheels. The brain activity in the mice of both groups was monitored with the aid of the customized micro array. Then the results were compared.

The group of mice with running wheels turned out to run on average six miles on a nightly basis after just one week had passed in the study. The researchers conducted four independent micro array analyses on the mice. They were able to identify thirty-three exercise-regulated genes in the hippocampus of the 'exercising' mice. Of these thirty-three genes, only six had been previously identified.

Through the course of the study it was determined that one special gene received the greatest boost through exercise. It is called VGF. If it is blocked, the mice showed behavior typical for depression, even though they exercised. Contrarily, when the scientists added even more VGF, they were able to observe an immense anti-depressant reaction.

As a result, anti-depressant drug development might find a new direction in targeting the VGF gene with a boosting function. The results of such a drug treatment should be faster compared to traditional chemical drug treatment as the VGF gene is already in the brain.