Diabetes drug metformin promotes myelin repair in rats

Professor Robin Franklin, from the MS Society Centre for Myelin Repair, described the new findings as "one of the most significant advances in myelin repair therapies there has ever been."

Regenerating myelin

To stop MS, we need to find treatments to repair myelin. But so far we haven't been able to reach this goal.

Our brains have the natural ability to regenerate myelin, the protective fatty coating around our nerves. This repair involves special myelin-making cells which are made from a type of stem cell called oligodendrocyte precursor cells (OPCs). But in MS and as we age, myelin repair stops working as well as it should.

The research published today in the journal Cell Stem Cell shows that this happens because OPCs lose their ability to transform into myelin-making cells.

Mimicking fasting

Building on this discovery, researchers found that when rats were given an alternate day fasting diet (meaning they ate every other day), OPCs returned to a "more youthful state" and recovered their ability to change into myelin-making cells. This led to an increase in myelin repair.

Most excitingly, the commonly-used diabetes drug metformin was able to mimic these effects without any actual fasting.

A significant advance

Professor Franklin said: "As with most regenerative processes, our body's ability to repair myelin declines as we age. The failure to regenerate lost cells called oligodendrocytes is associated with irreversible degeneration in MS, so regenerative therapies have been a long sought after but elusive goal.

"The findings shed light on why cells lose their ability to regenerate myelin, and how this process might be reversed. Although research so far has been done in rats, we hope to move it forward into humans soon.

"MS is relentless, painful, and disabling, and - while it's early days - this discovery could lead us to vital new treatment targets for progressive forms of the condition."

Treatments for everyone with MS

Dr Susan Kohlhaas, our Director of Research, said: "More than 100,000 people live with MS in the UK and many don't have treatment. The treatments that do exist only work on the immune system, and only help people with the relapsing form of the condition. We can see a future where nobody needs to worry about MS getting worse, or eventually needing a wheelchair, but for this to happen we need treatments that repair myelin.

Professor Franklin's research demonstrates myelin repair therapies are within our grasp, and we're closer than ever to finding treatments for everyone living with MS."