Keio University and Washington University in St. Louis have begun clinical research on slowing the aging process in humans with nicotinamide mononucleotide (NMN), a compound that has produced encouraging results in rodents.

The two universities are studying the effectiveness of the compound as a nutritional supplement to prevent diseases and extending the healthy life spans of humans.

“Once safety is confirmed, we want to scientifically verify if NMN is effective in boosting the working of organs that gradually declines with aging,” said Hiroshi Ito, a professor of internal medicine at Keio University.

NMN converts into nicotinamide adenine dinucleotide (NAD), which is vital to the body's energy metabolism. Experiments on mice demonstrated that NMN activates sirtuin genes that hold the key to longevity and has a curative effect for diabetes.

NAD forms in the human body, but decreases in number in many internal organs with age.

The test subjects are 10 healthy men aged between 40 and 60. The universities will try to access the safety of NMN and how the compound is absorbed in the body.