A common diabetes drug comes with a useful side effect.
More than 787,500 Australians have been diagnosed with type 2 diabetes; and if they are taking metformin to control their glucose levels, they could be recieving a brain boost at the same time.
According to new research from the University of Toronto in Canada, metformin can help our brain stem cells turn into nerve cells. The discovery could lead to a novel approach for treating people with brain injuries or neurodegenerative diseases.
“If you could take stem cells that normally reside in our brains and somehow use drugs to recruit them into becoming appropriate neural cell types, then you may be able to promote repair and recovery in at least some of the many brain disorders and injuries for which we currently have no treatment,” says professor Freda Miller, lead author of the study published in Cell Stem Cell.
The research team first realised that this could be happening when they discovered a pathway, aPKC-CBP, that signalled embryonic neural stem cells to produce neurons. Their collaborators at John Hopkins Medicine had discovered that metformin activated the same pathway for liver cells to help it control glucose levels.
They put two and two together, Miller says, and wondered whether metformin could activate the same pathway in neural cells and encourage brain repair. When it was tested with cultured cells, the researchers found that the metformin promoted differentiation in human and mouse neural stem cells.
It was then administered to seven-month old mice and found to promote an increase in the birth of new neurons in their brains. “Thus, metformin promotes neurogenesis by activating an aPKC-CBP pathway both in culture and in vivo,” the researchers state in the study.
Metformin also appears to enhance spatial memory formation in the brains of the mice. When adult mice taking the drug underwent a water maze test, it increased their ability to learn and remember the location of a hidden platform.
“As a next step, we would be interested to see if individuals with acquired brain injury might benefit from taking metformin,” Miller says.
There are also hints that the drug may have cognitive benefits for people with Alzheimer’s disease by enhancing brain repair. Furthermore, a mouse model has indicated that it delays the onset of cognitive impairment in individuals with Huntington’s disease.