As anyone who's seen a photo of Dwayne Johnson with curly hair can attest — some people were simply meant to be bald. But for the millions of people who have baldness thrust upon them – by genes, ageing, hormones or a medical condition – a new discovery may have just brought them a little bit closer to a lusciously hairy scalp.
That’s thanks to a new study published in the journal Nature Communications.
The scientists involved in the study experimented on mice to better understand how hair follicles regenerate and why some of them die off.
All the hairs on our body and hair follicles under our skin go through cycles of growth, death and rest. Hair follicle stem cells play an important role in regulating new growth.
The researchers discovered a protein called MCL-1 and investigated what it did by turning it off and seeing what happened to the mice.
“The authors have used sophisticated tools of molecular biology to essentially take away the protein and ask what happens,” Prof Sheila MacNeil, a tissue engineering specialist who was not involved in the study, told BBC Science Focus.
“While the tools are sophisticated, the approach of taking away the piece of the puzzle is classical physiology,” she said. “What does it do? What happens when we take it away? What happens when we put it back?”
In some mice, the scientists turned off MCL-1 from birth, and in others, they suddenly turned it off when the mice were adults, after removing a bit of their hair.
Without MCL-1, the scientists found that hair follicle stem cells seemed to die off, so new hairs wouldn’t grow. In the baby mice, this led to gradual hair loss; in the adults, their bald patches didn’t grow back.
The team concluded that MCL-1 seemed to protect hair follicle stem cells, allowing new hairs to grow when old hair follicles had died. Without MCL-1, hair follicles couldn’t regenerate.
MacNeil said this research provided “a proven credible target” for further investigation. For instance, scientists could now go on to find out whether humans experiencing hair loss also show signs of MCL-1 damage or try to find ways to protect the protein and stop baldness in its tracks.
But Prof Dorothy Bennett, a cell biologist at St George’s, University of London, told BBC Science Focus that turning this research into a treatment for baldness would be difficult. Bennett was also not involved in this research.
“MCL-1 is a protein that acts inside the cell that makes it, and complete proteins cannot usually pass through cell membranes to enter a cell,” she said. “So, even if we had a solution or ointment containing MCL-1, it is very unlikely that we could rub it on the scalp and expect any protein to reach the inside of any stem cells.
“Nor can we swallow it as a pill, since the digestive system breaks down proteins into amino acids and absorbs those as nutrients.”
However, Bennett noted that the paper also identified a potential workaround: activating another protein, called epidermal growth-factor receptor, appeared to boost MCL-1 levels. This could offer a promising alternative – though she cautioned that there are still “many ifs and maybes" developing such treatment.
Read more:
- Balding cure: We may finally have a simple way to reverse hair loss
- Scientists may have finally found a cheap, natural cure for baldness
- Scientists might soon cure balding. Here’s how
About our experts:
Sheila MacNeil is an emeritus professor of biomaterials and tissue engineering at the University of Sheffield, UK. MacNeil has expertise in tissue engineering of soft tissues (skin, oral mucosa, urethra and cornea) with a focus on translating research to the clinic. She has over 550 peer-reviewed articles to her name.
Dorothy Bennett is a research professor of cell biology at City, St George's, University of London, UK. Her research interests are in cell senescence (programmed permanent arrest of cell proliferation, which links ageing and cancer), and the genetics of melanoma and other pigmentary skin conditions.
