Metformin decelerates aging clock in male monkeys

Metformin, produced by Merck in Darmstadt, Germany, is the second most prescribed drug in the US. It is inexpensive and has been used to control blood sugar in type 2 diabetes for 60 years. Now, a group of Chinese and American researchers have succeeded in a proof-of-concept experiment to show that it can reduce cellular aging in older, male crab-eating macaque monkeys (who are similar to humans physiologically and even behaviorally, using tools, stealing, and bargaining).

Guang-Hui Liu and his associates at the Chinese Academy of Sciences and Altos Labs San Diego Institute of Science fed 12 macaques metformin at a normal diabetes dosage for 40 months (13 years in human time). Two control groups were formed, one of elderly monkeys and the other of younger monkeys. Using advanced molecular and cellular techniques and tissue samples from the monkeys, they were able to construct a time clock for cellular change in numerous body organs against which tissues from the treated monkeys could be compared.

The organs of the treated monkeys showed significantly slower signs of aging. Neuronal tissue, for example, were similar to tissues of monkey’s six years younger (equivalent to 18 years in humans). Not only were the effects of metformin promising, but their procedure allowed researchers to identify the mechanism of the results.

Liu and his associates plan a large human study supported by Merck. In the United States, efforts are being made to fund an even larger human study.

The study was published in Cell, September 12, 2024 (paywall). A somewhat lengthier summary is available in Science Direct. I based my information mostly on the news article in Nature, September 12, 2024.