Chinese and US researchers have reported metformin – used to treat type 2 diabetes – can slow ageing in multiple organs, including the brain, in cynomolgus monkeys.
Their study over 3.5 years by teams from several institutions – including the Institute of Zoology and Beijing Institute of Genomics (both part of the Chinese Academy of Sciences) – found monkeys treated with metformin showed reduced age-related decline, with some exhibiting a 6-year regression in certain ageing indicators.
Metformin improves insulin sensitivity, reducing inflammation and promoting cellular repair processes – all important factors in ageing.
The study, published in the journal Cell, used cynomolgus monkeys, which share many physiological and functional similarities with humans.
Previous animal studies evaluating effects of metformin on rodents, flies and worms have reported signs of rejuvenation, while human studies have indicated it can delay the onset of age-related diseases.
In the new study – a 40-month investigation aimed at better understanding metformin’s effects on biological ageing in mammals – metformin was administered daily to 36 monkeys, with tissue samples collected from multiple organs, brain imaging conducted, and physical and cognitive tests performed at intervals throughout the study to assess changes in biological age at the cellular level.
The team found evidence biological ageing slowed down in several organs, including kidneys (by 4.9 years), lungs (5.1 years) and skin (2.6 years).
The team also employed machine learning models to create a ‘multi-dimensional framework for assessing ageing in primate tissues and organs’, enabling a precise evaluation of metformin’s systemic anti-ageing effects.
Most notably, the researchers observed a significant impact on brain ageing: all monkeys experienced a reduction in age-related decline, with some showing brain age indicators resembling those of monkeys 6 years younger. Metformin also preserved brain structure and improved cognitive function, likely due to its activation of Nrf2, a protein known for its anti- oxidative properties.
This discovery ‘offers scientific insight into metformin’s geroprotective mechanism and will guide the development of therapies aimed at ageing intervention’, noted medicalnewstoday.com.
The geroprotective effect was especially pronounced in the brain’s frontal lobe and the liver: the analyses revealed metformin significantly slowed ageing of some neural cells and liver hepatocytes.
The researchers acknowledged limitations of their study, including its focus on a single gender and lack of human trials to confirm the findings and understand wider side effects.
