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Since the start of dawn, the phenomenon of hair loss has perplexed humanity. Over thousands of years of attempts to permanently reverse the problem, the quest to finding a cure is almost coming to an end. Many aspects of the molecular mechanism of androgenic alopecia have finally been unraveled. However, particular sequences of the events are still a mystery, creating an obstacle towards a permanent solution. Below, we will discuss the molecular mechanism of androgenic alopecia and current solutions to the problem.
Molecular mechanism of androgenic alopecia:
According to a study conducted by NCBI, various events take place in the cell that eventually leads to the premature dormancy of follicular units. The condition is often simplified into a matter of androgen-sensitivity and androgen resistance that varies between follicular units which are genetically predisposed. The varying properties of androgen-sensitivity are what creates the notorious distinct pattern of hair loss in androgenic alopecia.
It was found that balding scalp tends to have higher numbers of DHT receptors than the non-balding scalp. In addition, an increase in the 5-alpha-reductase enzyme activity miniaturization in areas of hair loss. 5-alpha-reductase is the enzyme that catalysis the conversion of testosterone to DHT (a stronger version of the hormone testosterone). The binding of DHT to androgen receptors found in follicular units triggers a signal transduction pathway that eventually stimulates the genes responsible for the mini their closing. The exact mechanism of how particular follicular units are androgen resistant based on their location on the body is not yet understood.
How hair loss is inherited:
For decades, we collectively decided to blame mothers for baldness, but the matter was merely a misunderstanding. The reality of hereditary hair loss is more complicated than to be determined with the presence or absence of a single gene. With that being said, there is some truth to the statement. The gene responsible for DHT receptors is X-linked, meaning the information relating to DHT receptors is inherited from the mother. However, hair loss is not entirely dependent on this single gene, but a collection of factors that co-function to result in baldness. A versatile range of sex-independent genes is involved that together could trigger the miniaturization of follicular units.
A permanent solution to hair loss:
Hair transplantation is currently the single permanent solution to hair loss in androgenic alopecia. In order for hair transplants to successfully reverse hair loss the patient has to have a region of stable hair growth. Androgenic alopecia, along with traumatic alopecia, mechanical alopecia, and traction alopecia meet the requirements.
The procedure operates on the different qualities of androgen sensitivity between follicular units to reverse balding. Hair transplants extract follicular units from areas of hair growth and relocating them to areas of hair loss. The characteristics of the harvested follicular units are predisposed, which prevents their loss in the process. In other words, if specific follicular units are androgen resistant and were relocated to areas of hair loss; the properties of the grafts will not be altered by mere re-positioning. Consequently, the grafts will adapt to the new position and continue to grow hair in the area.
Hair transplants can be performed in two methods, FUE and FUT. The remaining methods are variants of the FUE.
FUT (Follicular unit extraction)
Follicular unit extraction is the first method of hair transplantation created. The technique adopts an invasive procedure where follicular units are harvested through the excision of a region of the scalp and later dissecting the strip. The wound that occurs as a result of graft extraction requires stitching leaving a linear scar on the scalp and possibility of permanent nerve damage in the area.
The extracted grafts are then preserved in a solution of Hypothermosol until channel-opening on recipient site is conducted which marks the beginning of the implantation phase.
FUE (follicular unit extraction)
Follicular unit extraction is what revolutionized the hair transplant field. The technique follows an immaculate approach in the extraction phase as opposed to FUT. A micro-punch is utilized to isolate individual grafts and later extract them leaving behind minuscule scars that cannot be seen with the naked eye. The remaining steps are a replica of the FUT technique.
DHI Choi FUE
Direct hair implantation (DHI) Choi is a technique that follows the same mechanism as the regular FUE up to the preservation of grafts. Once the grafts are extracted with micro-punch and forceps and preserved in a Hypothermosol solution, DHI Choi first loads the grafts in a pen-like needle that simultaneously opens channels on the recipient site and implants the grafts.
Sapphire FUE differs from traditional FUE in the material of the equipment used. The blades used in the channel opening in sapphire FUE are made of sapphire. Given the properties of the stone, the blades are transparent and with a sharper tip that helps surgeons be precise with incision making.
Not every case of androgenic alopecia can be reversed with hair transplants. Since the success of the surgery depends entirely on stable hair growth regions to extract follicular units and relocate to the balding scalp, patients need to have a sufficient supply of donor grafts. It is not up to patients to determine whether their donor regions could cover their hair loss regions. Instead, hair transplant centers like the Vera Clinic offer virtual consultation free of charge. During the online consultation, a medical specialist will request pictures of your scalp from various angles to assess your case.
Alternative treatments to hair transplants
In case a patient is not interested in hair transplants or isn't a suitable candidate for the surgery, an array of non-surgical solutions can reverse hair loss.
PRP (platelet-rich plasma) therapy works on extracting growth factors from the patient's blood and injecting it into the scalp. Growth factors are proteins that act as extracellular signaling to trigger a cascade of events within the cell that lead to proliferation.
Since PRP uses the patient's own cells, there is no risk of side-effects. As for the treatment schedule, PRP is taken once per month, and a patient may need anywhere between one to eight sessions per year depending on their degree of hair loss. For patients with high hair loss areas, PRP therapy may not be effective.
Minoxidil is a solution applied to the scalp that restores hair loss through an unknown mechanism. In order for the spray to work effectively, patients must use it twice daily. Hair loss will re-occur once the medication stops. Side effects of minoxidil include increased body hair growth.
Finasteride is a pill that patients have to take daily to reverse hair loss through inhibiting the enzymatic activity of 5-alpha-reductase responsible for the conversion of testosterone to the stronger version DHT. If the patient stops using Finasteride, hair loss will presume.
Hair loss is a phenomenon that emotionally daunts the ones suffering from it. For years, we have progressively been getting closer to a permanent cure. The more we understand the condition, the easier it is to combat it. Thus far, we realize that follicular units can either be androgen-sensitive or androgen resistant. The androgen resistance and sensitivity are genetically predisposed. However, contrary to popular belief, mothers aren't entirely to blame for hair loss. Instead, a combination of sex-independent genes is involved
The polarizing differences in androgen sensitivity are what produces the notorious pattern of hair loss in androgenic alopecia. In addition, areas of hair loss tend to have higher numbers of DHT receptors and increased activity of the 5-alpha-reductase enzyme. What remains a mystery, however, is how DHT has contradicting effects on follicular units based on their location on the body. While the picture is almost complete, the remaining gaps are hindering the quest to discovering a permanent cure.
A non-surgical cure may be coming in the future, but for now, hair transplants are the only permanent solution to androgenic alopecia — the procedure functions on the different characteristics of androgen sensitivity between follicular units. Grafts are extracted from areas of stable growth and relocated to areas of hair loss. The relocation of follicular units does not affect their properties, and the grafts continue to initiate hair growth in the area.
Alternative treatments like minoxidil and finasteride are not permanent and require daily use to maintain their effects. PRP-therapy, on the other hand, is split into monthly sessions and patients may need anywhere between one to eight sessions.