The revolutionary advances in biology have armed scientists with powerful new tools to learn and understand the body’s complex chemical changes: including the development of new treatments of hair loss. George Cotsarelis, MD—director of the Hair and Scalp Clinic at the University of Pennsylvania—reports that the last 5 to 7 years has seen “a boom in the understanding of hair loss.” Because scientists and researchers have made huge strides in basic research, they are now attempting to convert those findings into clinical benefits.
A closer look at the hair follicle illuminates its most unusual feature: it is self-regenerating. Hair follicles live below the top layer of the skin; at the base of the follicle is the hair bulb, where rapidly growing matrix cells become hair. The bulge—located further up the follicle—is where follicle stem cells live: self-renewing cells that divide upon receiving the correct set of chemical signals. Yet these stem cells do not divide like other, normal cells, in which both halves become new cells that continuously split and divide. Only one half of the follicle stem cells operates in this way; the other half becomes a new stem cells that stays for future regeneration.
The hair growth cycle is comprised of phases of growth (anagen), regression (catagen), rest (telogen) and shedding (exogen). While losing hair is a normal physiological part of growth and replacement, as hair follicles go through the growth and resting cycles in a non-synchronized fashion, there can be common problems:
• Androgenetic Alopecia: Commonly known as male pattern baldness, and caused by a byproduct of testosterone called DHT, androgenetic alopecia occurs when hair follicles get smaller: resulting in thin, very short hairs—and many follicles lacking hair shafts.
• Telogen Effluvium: This process involves increased hair shedding; many—if not most—of the hair follicles entering the exogen stage at once.
• Chemotherapy-Induced Alopecia: Chemotherapy forces growing hair follicles into the catagen stage. Because the hair shaft does not develop properly, the hair breaks and subsequently falls out. Yet once chemotherapy concludes, the follicles are able to regenerate.
• Alopecia Areata: When a person’s immune system attacks the cells of the growing hair bulb, this autoimmune condition forces hair follicles into the catagen phase. Hair breaks and falls out, often in patches scattered along the scalp. This condition is unrelated to a more severe condition known as cicatricial alopecia, in which the immune system attacks the stem cells in the bulge of the follicle—resulting in permanent hair loss.
Hair restoration, a symptom largely associated with aging, is also dictated by the decline of mitochondrial function within cells. In a paper published in the journal Nature, researchers recently reversed both wrinkled skin and hair loss in mice by restoring mitochondrial function. Keshav Singh, from the University of Alabama at Birmingham, and colleagues experimented with ways to reverse a DNA mutation that leads to mitochondrial dysfunction: in working with their mouse model, the researchers were successful in restoring mitochondrial function—thereby reversing the wrinkles and hair loss observed in the rodents.
Many other researchers are investigating future hair loss treatments, including studies that involve getting shutdown follicles to regenerate. Other drugs for hair-loss treatments involve specific shampoos, topical treatments, and scientific supplements. The SBS recently announced Hair Restoration track, taking place on Saturday, February 9th, will be spearheaded by Glynis Ablon, MD: featuring live demonstrations, an interactive panel discussion, and the latest updates in hair restoration and clinical treatments. Matt Leavitt, DO, FAOCD will additionally co-chair a session focused on hair loss at the track. Dr. Leavitt is recognized both nationally and internationally for his work in hair restoration, and has been interviewed by Forbes, Men’s Vogue, International Herald Tribune, Healthy Aging, Playboy, Men’s Health, and numerous other publications.
SOURCES
https://www.sciencedirect.com/science/article/pii/S0022202X15417737
https://www.nature.com/articles/s41419-018-0765-9
https://www.medicalnewstoday.com/articles/322558.php
https://www.webmd.com/skin-problems-and-treatments/hair-loss/features/sweet-hair-after#1
