Most of us used to believe that hair loss is something caused by such factors as stresses, poor nutrition and improper lifestyle, genetics, bad habits, or simply just being a man. However, there is one more factor which contributes to hair loss in pretty great number of people. Those are various traumas, wounds, physical damage of skin, and other similar things. Some people lose their hair as a result of the mentioned factors, and unfortunately they have to face the fact that it is almost impossible to re-grow hair after that. Not much is known about the causes and the issues that play a role in this situation, and a great number of studies is being conducted to understand why it is impossible to go through normal hair regeneration procedure after a trauma or any physical skin damage. Recently, a group of scientists from the Perelman School of Medicine at the University of Pennsylvania published some interesting findings related to the issue.

The scientific team attempted to look closer at the phenomena on chemical level, and it was found out that during wound healing or other skin damage healing, a special chemical known as Fgf9 and called by the scientists as growth factor occurs in decreased amounts in skin cells. This chemical is believed to be responsible for normal hair regeneration and normal hair follicle development. The scientists managed to explain the processes linked to regular hair restoration when Fgf9 is involved, and they tried various ways to assist skin cells after trauma or physical damage to restore normal amounts of this chemical. For that, they used a mouse model and got an opportunity to analyze the process closely. They could observe that unlike it is in humans (after suffering a trauma, hair follicle growth is blocked in adult humans and only skin cells regenerate with a scar), in mice hair regeneration after trauma is possible, and wound healing process in mice helps them to re-grow their hair.

In order to get an answer to the question why is this happening, the scientists compared the processes that going on in the cells of adult humans and mice. It turned out that in contrast to mice, humans have reduced number of specific cells known as gamma delta T, so the researchers suggested that this can be the key to the issue. They found out that in mice, the Fgf9 component comes from gamma delta T cells and helps animals to boost their abilities of post-traumatic hair regeneration. It turned out that in post-traumatic period, the concentrations of gamma delta T cells and Fgf9 in mice was increasing drastically and reaching up to 200-300 per cent increase. That is why hair regeneration process was very speedy and successful, unlikely to the situation with gamma delta T cells in adult humans after skin traumas.

To prove their hypothesis, the scientists added Fgf9 component to the wounds of mice, and as a response hair regeneration process has become even faster. “The findings help explain why humans don’t regenerate their hair after wounding. The study also points us to a way to treat wounds and grow hair,” the study leader George Cotsarelis commented on the research. He underlined that now, the team is thinking about using the findings for creating a special therapy helping people after traumas to restore their hair. The treatment is intended to be directed to compensating a lack of Fgf9 compound causing inability to restore hair in humans. “Testing activators of Fgf9 or Wnt pathways during the wound healing process may be warranted,” the study leader said. Those who are interested in getting more information on the point can check out the report about this study published recently in one of the issues of the journal Nature Medicine.