Nature aging: The reason for baldness was found!The hair follicle stem cells did not die, but they escaped secretly
For young people in contemporary China, hair loss is the biggest crisis. According to the “Chinese Hair Line People”, there are 200 million hair loss people in my country, about 130 million men, and about 70 million women.
Normal hair that falls off is hair that is in the retreating period and resting period. Since the retreating period and the newly entered growth period are constantly dynamic balance, the normal number of hair can be maintained.
Pathological hair loss is due to various reasons, such as male androgen, such asrogen hair loss, neurological hair loss, endocrine hair loss, nutritional hair loss, and physical and chemical factors. These eventually lead to changes and malnutrition of hair follicle hair nipples, which leads to hair growth function suppression. A large amount of hair enters the rest period and hair loss appears.
Handicular stem cells escape instead of death, causing hair loss
Chinese scientists from Northwestern University found that among the old mice, epithelial cells escaped to the dermis, causing the hair follicles to be miniaturized. In addition, the researchers’ live imaging captures the process of relocation of a single epithelium cells from the hair follicle stem cell area and the disintegration of the hair follicles (as shown).
In other words, the reason why aging people/animals are sparsely hair is not because the hair follicle stem cells died, but because they escaped!
This study clarifies an unknown event that ecological escape from its ecological location. This is a potential mechanism for reduced hair follicle stem cells and tissue degeneration. The relevant content was published on October 4, 21st in the “Nature · Aging” magazine.
The scientific research team observes the hair follicle stem cells of the KRT14-H2BGFP mice with a group of protein H2B green fluorescent protein (H2BGFP). The results showed that the 6-8 months old young mouse hair follicle stem cell group was located below the sebaceous glands. The space was very clear. However, the number of elderly mouse follicle cells above 20 months decreased significantly, the position was moved up, and the volume of the hair follicle was significantly reduced.
The most common cause of this result is the death of hair follicles stem cells. Surprisingly, researchers specifically analyzed the number of apoptotic cells in young mice and aging mouse hair follicles, and found that there was no difference.
There was no apoptosis, and the only reason for the narrowing of aging hair follicles was the escape of hair follicles stem cells. It was found that about 5.8%of aging hair follicles appeared similar to the “escape” of cells, and the shape of the hair follicles with cell escape was obviously shrinking significantly than the hair follicles without escape.
What causes the hair follicle stem cells to escape?
Then, using the skin epithelial cells sources of young mice and old mice for single -cell sequencing, researchers found that cell adhesion and extracellular matrix (ECM) related genes in aging tissue were reduced. Researchers used molecular biology technical methods to find two importantly -downgraded genes, Foxc1 and NFATC1. The lowering data of FOXC1 and NFATC1 in aging HF-SCS further support the connection between FOXC1 and NFATC1 expression reduction and HF-SCS aging.
After finding possible genes, the researchers built the double knock removal of these two genes. Essence Double -knocking mice did not show other abnormalities.
Double -knocking the genes of cell adhesion regulatory and cell proliferation negative regulation in the two -knocking of mice’s hair follicle stem cells, such as ACTG1, CD34, ITGB6, and NPNT. Compared with aging mice, double knocking from mouse hair follicle stem cells escape more.
Researchers concluded that this study provides evidence for the exhaustion of hair follicles stem cells and a new model of hair follicles. Aging HF-SCS cannot maintain many specific cell adhesion and extracellular matrix gene expression. At least part of the reason is that FOXC1 and NFATC1 are reduced. Conversely, the damaged micro-loop and reduced cell adhesion allowed epithelial cells to escape from the HF-SC area into the dermis, causing SC failure, and eventually HFS degeneration.
Simply use an analogy that the soil is lost, the seeds do not have a good environmental growth, so they escape.
The hair follicle stem cells sneak the road, making the scalp that is not rich worse. However, it is clear that the two important genes of FoxC1 and NFATC1 have already leaped in hair loss research, which pointed out a new way for the treatment agent that stimulates the stimulating head. Scientific researchers work harder and transform into effective anti -proof products as soon as possible to save people.
<!-2528: Dermatology terminal page
references:
Escape of Hair Follicle STEM CELLS CAUSES STEM CELL Exhaustion During aging. Nature aging Volume 1, Pages 889–903 (2021). Published: 04 October 2021
