Scientists have been able to show that injections of klotho, a naturally-occurring protein that declines in mammals with age, can improve the cognitive function of aging monkeys, according to a new study.
Before being tested in primates, klotho — named after Clotho, one of the three mythological Fates — had shown promising cognitive benefits in mice.
The new study, which was conducted by a team of American researchers and published this week in the journal Nature Aging, shows promise that restorative klotho treatments might achieve similar cognitive results in aging humans.
"Given the close genetic and physiological parallels between primates and humans, this could suggest potential applications for treating human cognitive disorders," Marc Busche, a neurologist at University College London who was not involved in the study, told Nature.
Despite these promising results, a lot more research needs to be done to fully understand why the protein leads to better cognitive function.
The researchers tested klotho treatments in older rhesus macaques, who were on average 22 years old. For context, as the researchers note in the study, that equates to roughly 65 human years.
To examine klotho's efficacy, the monkeys were subjected to a relatively simple spatial memory experiment. As study co-author Dena Dubal, a physician-researcher at the University of California, San Francisco, described to Nature, the experiment was the equivalent of asking a human to remember where their car is parked. The researchers first hid a certain snack away in one of many wells, then prompted the primates to recall where the treat had been hidden.
Per the study, the macaques were at first only able to correctly remember where the snack had been hidden roughly 45 percent of the time. But after receiving a klotho injection, they correctly located their treatments 60 percent of the time — a small but significant cognitive improvement that lasted for about two weeks after injection.
The primates were more receptive to low doses of the protein than higher doses, a stark contrast from the results of previous mice trials.
But the results should be taken with a grain of salt. For one, it's still unclear why exactly the molecule is effective.
More research is needed to trace the mechanisms behind these cognitive benefits, and researchers say they're hoping to see the protein soon make its way to human clinical trials.
The hope is also that klotho treatments may one day play a role in treating cognitive diseases like Alzheimer's. A recent study showed that Alzheimer's patients with relatively high natural klotho levels experience less cognitive impairment.
While we still have a lot of questions to answer, the research "certainly gives us hope," Dubal told Nature, "and there's a very strong reason to jump into human clinical trials now."
More on memory and cognition: High Blood Pressure May Cause Dementia, Scientists Say
Share This Article