Why hair loss and how to prevent it

A team of researchers from Australia, China and Singapore has discovered that hair follicle stem cells – the main players in hair growth – need a special protective protein called MCL-1. If they lack it, the cells are stressed, destroyed and hair growth stops.

Hair follicles go through several stages of development: active growth, slowing down and resting. When the resting phase occurs, the hair falls out and then the cycle begins again. However, if stem cells are damaged or destroyed at this point, new hair does not appear.

To understand the role of MCL-1, the researchers removed this protein from mice and monitored their condition. If the deficiency occurred at birth, the structure of hair follicles remained unchanged, but with age there was a gradual baldness. When the protein was removed from adult animals, hair loss was rapid and growth did not resume.

The removal of MCL-1 led to the fact that the active stem cells experienced severe stress, triggered the protein P53, responsible for cell death, and follicles were destroyed. However, when the researchers turned off P53, the shedding process stopped even when MCL-1 was deficient. This discovery confirms that the interaction of these proteins plays a key role in preserving hair follicles.

The experiments also showed that the MCL-1 protein is maintained through a specific ERBB signaling pathway that regulates cellular processes. An in-depth study of these mechanisms will help to create new methods of combating baldness and develop drugs that will allow to restore hair.