Stem cells have the “self-duplication capability,” a function to divide and make copies of themselves, and the “differentiation capability,” which is a function to make various types of cells.
It is the work of the stem cells which helps to maintain our bodies healthy and heal wounds. Stem cells renew and aid the regeneration of all other cells in the body – including those of the skin, nails and hair. These regenerated cells are called adult stem cells. They reside in some adult tissues only.
Recently in the medical field, research has been active on “regenerative medicine,” which utilizes the stem cells to repair illness- and injury-damaged organs and tissues.
In 2009, a research team at the University of Toronto discovered a therapeutic application for restoring hair growth in those suffering from hair loss (alopecia)—and in those combatting the underlying causes that lead to the telltale signs of a damaged scalp. Their research was in the area of adult stem cells.
There are two types of stem cells – “dermal stem cells” and “epidermal stem cells.” Each type has its own role.
Dermal Stem Cells | Epidermal Stem Cells | |
|---|---|---|
Location | In dermis (deep seated under the epidermis), localized at the base of the hair follicle (dermal papilla) | In epidermis (on the scalp surface), the hair bulge forms a reservoir of epidermal stem cells. |
Function | Generate fibroblast, has the property to grow in colonies in the form of spheres.
Support dermal rejuvenation and generate hair follicle formation and stimulate hair follicle formation and hair growth.
Dermal stem cells that serve to induce hair morphogenesis and maintain the dermis. | Continue regeneration of the hair follicle during cycling. Has an important role in hair cycle turnover process, from anagen, catagen to telogen. |
When suffering from hair loss, the telogen phase is prolonged, and the transition to the anagen phase becomes more difficult. Hair become thinner and the percentage of hair transitioning to the telogen phase continues to increase.
The problem comes from the fact that the hair follicle stem cells (also called ORSc) located in the bulge along the hair, are less productive, and less adapted to improve the quality of the matrix (made of keratinocytes) supporting the hair follicle growth. Furthermore, the fibroblasts located in the dermal papilla (also called HFDPc) are less efficient in communicating with the stem cells, meaning that the matrix will not be renewed as it used to.
Initiating the anagen phase becomes more sluggish, and hair loss becomes a part of daily life.
When the telogen phase is prolonged and the transition to the anagen phase becomes more difficult, extended hair loss occurs.
Hair becomes thinner. The percentage of hair transitioning to the telogen phase increases.
This happens when hair follicle stem cells, also called ORSc, become less productive, less adaptive to improving the quality of the matrix that supports follicle growth. This matrix is made of keratinocytes. Furthermore, the fibroblasts located in the dermal papilla, called HFDPc, are less efficient in communicating with the stem cells, resulting in the matrix no longer renewing as it used to.
Thus initiating the anagen phase becomes more sluggish, and hair loss becomes an eventual part of daily life.
Men
Women
Men | Women | |
|---|---|---|
110,000 Hair | Average no. of hairs on a global surface of 600cm2 in the human scalp | Average no. of hairs on a global surface of 600cm2 in the human scalp |
50-100 Hair | Scalp hair lost each day | Scalp hair lost each day |
25% | - | Percentage of women has thinned hair |
40% | Percentage of men with noticeable hair loss by age 35 (this reaches 65% by age 60!) | During menopause, 4 out of 10 women suffer from thinning hair |
95% | - | Percentage of female hair loss results from hormonal changes, as in pregnancy or menopause |
Men
Scalp hair lost each day
Percentage of men with noticeable hair loss by age 35
(this reaches 65% by age 60!)
Women
Scalp hair lost each day
Percentage of women has thinned hair
Percentage of female hair loss results from hormonal changes, as in pregnancy or menopause
During menopause, 4 out of 10 women suffer from thinning hair
