Metformin, which is the world's most extensively used anti-diabetic drug, decreases ageing and increases lifespan, says new evidence found by Belgian doctoral researcher Wouter De Haes (KU Leuven).
The researchers teased out the mechanism behind metformin's age-slowing effects: the drug causes an increase in the number of toxic oxygen molecules released in the cell and this, surprisingly, increases cell robustness and longevity in the long term.
Mitochondria - the energy factories in cells - generate tiny electric currents to provide the body's cells with energy. Highly reactive oxygen molecules are produced as a by-product of this process.
Wouter De Haes explained that as long as the amount of harmful oxygen molecules released in the cell remains small, it has a positive long-term effect on the cell. Cells use the reactive oxygen particles to their advantage before they can do any damage.
Metformin causes a slight increase in the number of harmful oxygen molecules. We found that this makes cells stronger and extends their healthy lifespan, he added.
The researchers studied the drug's mechanism in the tiny roundworm Caenorhabditis elegans, a species which has a lifespan of only three weeks, and found that as the worms age, they get smaller, wrinkle up and become less mobile. But worms which were treated with metformin showed very limited size loss and no wrinkling, said Wouter De Haes.
The study was reported in the journal Proceedings of the National Academy of Sciences.