BUFFALO, N.Y. -- Ginkgo biloba, prescribed widely in Europe to improve brain function, appears to improve learning and memory in rats and prolongs their life, a study at the University at Buffalo has shown.
The unexpected positive effect on longevity has surfaced in research to determine ginkgo biloba's effect on age-related cognitive deficits, using rats as an animal model.
"At a certain point in our analysis, we realized that the rats who were receiving ginkgo biloba were living substantially longer than those who were not receiving the extract," said Jerrold C. Winter, Ph.D., professor of pharmacology and toxicology in UB's School of Medicine and Biomedical Sciences and author of the study.
"That finding leads us to speculate that in addition to ginkgo biloba's purported beneficial effects on brain function, which our study supports, the extract may also have a positive effect on longevity."
Results of the study appear in the current issue of Physiology and Behavior.
Ginkgo biloba is available in the U.S. as a dietary supplement, but is not approved by the FDA as a medical treatment. It is prescribed widely by physicians in Germany and France in the form of EGb 761 -- a complex mixture of chemicals obtained from ginkgo leaves -- to treat age-related deterioration in brain function. Several human trials there have shown positive results, but little research has been done to replicate these findings in animals, Winter said.
Winter's earlier research with rats showed that a set of tasks performed in an apparatus called the radial maze could reliably detect deficiencies in learning and memory related to age. In the current study, Winter used 20-month-old rats, which were assigned a diet that included either ginkgo biloba extract or no extract. Over several weeks, the animals performed tasks in the radial maze that required them to master new challenges and retain learned information over time.