Sometimes the mere act of eating can make us happy, but new research suggests that consuming the right foods is enough to relieve depression. Two nutrients found in foods such as fish, walnuts, and beets worked as well as prescription antidepressants in preventing depression in rats. The findings may shed new light what causes the disorder and may lead to new therapies for depression.
Despite decades of research, scientists are still puzzled about what exactly happens in the brain during bouts of depression. Some cultures suffer less from the disorder, and many researchers believe diet plays a role. But teasing out the culinary panacea has been slow going. Research has linked omega-3 oil, available as an over-the-counter nutritional supplement, to cardiovascular health, and it also appears to improve mood and cognitive function. Other studies suggest that the nutrient uridine also affects brain function.
A team of researchers led by neurobiologist William Carlezon at Harvard's McLean Hospital in Belmont, Massachusetts, studied how omega-3 fatty acids and uridine affect the behavior of rats using a standard depression test. Rats forced to swim in chilled water with no way to escape will normally become hopeless and float motionlessly. But when treated with prescription antidepressants, rats remain active longer, searching for an escape. The team found that rats whose diets were supplemented with high levels of omega-3 oil for at least 30 days stayed active and focused on escape. Similarly, rats injected with high levels of uridine were equally tenacious. These results were not seen in untreated rats, the team reports in the 15 February issue of Biological Psychiatry.
Both compounds are believed to play a role in mitochondrial function. Omega-3 is thought to make the mitochondrial membrane more flexible, thereby improving the flow of chemical signals. And uridine fuels chemical reactions in mitochondria and may boost the cellular communications that control mood and other mental processes. Therefore, in addition to leading to new potential therapies for depression, this work indirectly hints at a role for mitochondria in mood disorders, say the researchers. The team now hopes to formulate a new uridine-based antidepressant treatment for humans.
The study makes a significant contribution to the field, says behavioral pharmacologist Irwin Lucki at University of Pennsylvania in Philadelphia. "Researchers can now contrast these natural antidepressants against the cadre of prescription treatments to gain new insight" into the molecular workings of depression.