For some men, the period of baldness could soon come to an end, because for the first time researchers were able to isolate stem cells from a hair root and grow hair with these of a naked mouse.
If this method can also be applied to humans, it could also help victims of burns.
In the study, published in the journal Cell Biology , scientists discovered that the metabolism of these stem cells works in a special way, different from what happens in other cells of the skin.
When you feed, digestion breaks down food into smaller particles, which can be absorbed at the cellular level. The main one is glucose: from it, the cells take away the energy they use to grow and multiply.
So far, the process is the same in both cases. But after breaking the glucose, the stem cells that are in the hair follicles can generate a by-product – as if it were a resulting waste of the process.
The substance, called pyruvic acid, has two paths to follow either back to the mitochondria of the cell, where it also turns energy, or becomes another by-product lactic acid. Yes, that same one, what your muscle cells produce when you spend too much time running on the treadmill.
The scientists then decided to test their hypotheses on a group of guinea pigs.
The first step was to block the production of lactic acid in the cells of some of the mice. The change prevented the activation of capillary stem cells, and hair growth of rodents. Bingo: it was the sign that lactic acid coordinates function.
This was proven in another experiment. Guinea pigs who had a genetic modification, to produce more lactic acid, as expected, kept
ligadone capillary cells – and hair growth more constant.
After unmasking the whole mechanism, the challenge was to find a drug that had the same effect. The researchers succeeded with two of them: RCGD423 and UK5099, who solve the problem in different ways.
While the former focuses on increasing the production of lactic acid, the other turns a larger loop, blocking the entry of pyruvate into the mitochondria and forcing the cell to produce the substance on its own.
Although not yet tested in humans, these drugs are expected to be used in the future in baldness or alopecia medications – the name given to aging hair loss or factors such as stress, hormonal imbalance, and chemotherapy.
Both cell types could renew themselves in a nutrient solution in the laboratory and differentiate into skin cells, functioning follicles and even sebaceous glands.
Just after the transfer of the stem cells by the researchers to the skin of a naked mouse, the latter grew a dense tuft of hair. In many cases, it was possible to regrow hairs that resembled the normal coat of a mouse.
Formation of a new skin
In the hair follicle itself, two growth factors that develop in the bulge of the hair root inhibit the differentiation of stem cells. They begin to differentiate and form new skin and hair. Only when the stem cells are out of the follicles.
The scientists used a new method to identify and extract the stem cells. Experiments had shown that the surface of the stem cells has a different structure than that of the other cells of the skin.
They use this property to mark the stem cells with two types of antibodies that attach to the specific surface structures and separate them from the other cells.
Some experiments had shown that the characteristic surface structures were found not only in mice, but probably also in human stem cells in hair roots. In addition, the mice from which the stem cells were taken did not need to be genetically modified.
The researchers believe that this method of obtaining stem cells could thus be applied to humans without ethical concerns.