To most of the world, it’s known as Easter Island, but to the people that live there it’s called Rapa Nui. Today scientists are experimenting with a little known compound from Rapa Nui called rapamycin with a potential to revolutionize medicine.
The bacteria streptomyces hygroscopicus was first discovered 37 years ago and since then has generally been used as an immunosuppressant in organ transplants. In 2009 however, Harvard researchers accidentally discovered that it also suppressed damaged proteins that cause aging. A year later they were using it to reverse symptoms of Alzheimer’s, and in 2011 scientists used rapamycin to counteract the debilitating effects of Hutchinson-Gilford progeria syndrome (HPGS), a disease that causes rapid aging in children.
In a new study, researchers at the University of Texas Health Science Center San Antonio have shown rapamycin to reduce anxiety, depression and increase memory in mice.
In the study, researchers gave mice a dose similar to that used in transplants and in various tests the mice exhibited less anxiety and depression, and were able to learn mazes faster. Reduced anxiety meant that mice would explore an unknown area for longer, and if under duress, would be less likely to give up.
“We made the young ones learn and remember what they learned, better than what is normal,” commented researcher Veronica Galvan, Ph.D. But the improvements weren’t only in the young mice, but old mice as well. “Among the older mice, the ones fed with a diet including rapamycin actually showed an improvement, negating the normal decline that you see in these functions with age.”
How exactly rapamycin works still isn’t clear, but researchers have found it boosts three important chemicals in the brain: dopamine (memory, happiness and learning abilities), norepinephrine and serotonin (mood and depression).
The next step for investigators will be a clinical trial on humans that haven’t responded well to traditional antidepressants.
Could rapamycin be the “elixir of life” for our century? Its vast potential is only beginning to be understood. It remains, like the great moai of its namesake, a mystery yet to be unraveled.