The antidepressant effects of a workout may one day come in a pill.
Exercise alleviates depression, but no one knows exactly how. Now Ronald Duman at Yale University and his colleagues have found a gene in mice that may mediate the effect. The team created a chip to screen for genes in the hippocampus whose activity is affected by exercise. The hippocampus is a part of the brain that is very sensitive to hormones and stress.
They found that long workouts on the running wheel ramped up the activity of 33 genes. One of them, called VGF – which produces a nerve growth factor of the same name – really stood out.
Further experiments showed that mice given synthetic VGF put more effort into a series of physical tests, whilst mice lacking a gene for VGF showed more depressive behaviour (Nature Medicine, DOI: 10.1038/nm166).
SSRI-based antidepressants such as Prozac don’t activate VGF but, intriguingly, electroconvulsive therapy – a controversial, but very effective treatment for depression – does.
Duman thinks that targeting VGF will be the next big thing in antidepressants. “It may provide a novel target with a different mechanism,” he says.
Source: From issue 2633 of New Scientist magazine, 08 December 2007, page 18
