What is androgenetic alopecia?
Androgenetic alopecia is non-scarring androgen-dependent hair loss. It affects both women and men of all ages. The disease can start already in the teenage years, but it can also occur, for example, after menopause.
There are two types of androgenetic alopecia:
- Male androgenetic alopecia /MAGA/also called AGA (androgenetic alopecia)
- Female androgenetic alopecia /FAGA/also called FHLP (female hair loss pattern)
The following scales are used to determine the stage of hair shedding:
- Norwood Hamilton (Fig. 1) – for AGA (MAGA) evaluation
- Sinclair (Fig. 2) – for FHLP evaluation
Sometimes, however, baldness develops in women according to the pattern typical for men, on the temples and crown of the head.
Fig. 1. Norwood Hamilton scale
Fig. 2. Sinclair scale
Why do women and men experience androgenetic alopecia?
Androgenetic alopecia has a genetic basis. The risk of AGA increases with a positive family history.
There are specific genes that are responsible for the development of AGA, including:
- androgen receptor (AR) and estrogen receptor (ERs) genes
- 5α-reductase genes
- Y chromosome genes
- Growth factor genes.
The cause of alopecia is hyperandrogenism, i.e., an excess of androgenic hormones.
Hyperandrogenism in men is associated with endocrine disorders or the use of androgens (e.g., very often to my office come bodybuilders who use testosterone).
In women, hyperandrogenism may be due to systemic disease (e.g., pituitary gland disease, PCOS, androgen-producing ovarian tumors, adrenal tumors, and obesity) or idiopathic hyperandrogenism.
However, not always in women with alopecia, the level of androgens is elevated. Most women are not found to have high levels in laboratory tests. This may indicate the role of other mechanisms unrelated to androgens’ influence. They are not fully understood, but in such cases, increased sensitivity of androgen receptors to the correct level of androgens in a woman’s body is suggested.
Another issue is post-menopausal women. In these women, alopecia is caused by a decrease in the concentration of estrogens and a disturbance in their proportions to androgens.
What is hair follicle miniaturization?
Hormones circulate in the human blood. The primary androgenic hormone is testosterone. The enzyme 5α-reductase (located in the hair papilla) metabolizes testosterone to DHT 5α-dihydrotestosterone, which binds to the androgen receptor (Fig. 3). Although testosterone also binds to the same receptor, DHT has a five times greater affinity for the AR. After attaching to the receptor, DHT triggers specific physiological processes in the hair follicle. The hair growth phase (anagen) is shortened from 4-7 years to several months or even weeks, and the telogen phase is extended to over three months. The percentage of telogen hair increases from 5-10% to even 20%. Hair falls out and becomes thin and short. Terminal hair miniaturizes into vellus hair (Fig. 4).
Fig. 3. Conversion of testosterone in scalp hair follicle
Fig. 4. Miniaturization of scalp hair follicles
How are AGA and FHLP treated?
There is no effective cure for androgenetic alopecia. Androgenetic alopecia is treatable. In this disease, slowing down the progressing changes and stimulating hair regrowth is possible.
Antiandrogens are a wide group of drugs and compounds that reduce the level or activity of androgen hormones in the human body in diseases such as androgenetic alopecia.
In this article, I present a group of plant extracts with study evidence of positive effects on the processes in the hair follicle in androgenetic alopecia.
| Plant extract | Active ingredients | Clinical/biological effect |
| Saw palmetto /Serenoa repens/ | – beta-sitosterols – fatty acids /lauric (16.5%), myristic (6.2%), oleic (29.8%)/ | – inhibits 5-α-reductase type I and II, – reduces the total amount of DHT by converting it to a weaker metabolite – has a strong anti-inflammatory effect and stimulates metabolism |
| Pygeum /Pygeum africanum/ | – pentacyclic triterpenoid saponins (ursolic acid and oleanolic acid) – triterpenes (β-amyrin) – phenols (ferulic acid, atraric acid and N- butylbenzenesulfonamide (NBBS)) – sterols (β-sitosterol) – fatty acids (lauric acid) | – anti-inflammatory – it is a 5-α-reductase inhibitor |
| Cucurbita pepo (pumpkin) seed oil | – fatty acids – phytosterols | – 5-AR androgen receptor antagonist |
| Green tea /Camellia Sinensis/ | – epigallocatechin gallate (EGCG) | – inhibits the enzyme 5-alpha-reductase, and thus reduce the conversion of testosterone to dihydrotestosterone /DHT/ |
| Coffee /Caffeine/ | – caffeine | – it is a phosphodiesterase inhibitor and increases the level of cyclic adenosine monophosphate (cAMP) and cell metabolism. As a result, it stimulates cell proliferation and stops shedding |
| Rosemary oil /Rosmarinus officinalis/ | – caffeic acid – rosemary acid – camphor – 12-methoxycarnosinic acid | – increases microcapillary perfusion, – increases the production of prostaglandin E2 – reduces the production of leukotriene B4 (produced during inflammation) |
| Grape skin /Vitis vinifera var. Merlot/ | – proanthocyanidins OPC | – they block the androgen receptor 5-AR, with which DHT binds, thus inhibiting hair miniaturization |
| Mint /Mentha spicata [Labiatae]/ | – essential oil containing: menthol, menthone and terpene compounds, and neomenthol – flavonoids – phenolic acids: coffee, chlorogenic, rosemary – triterpenes | – reduces the level of free testosterone, – increases the level of LH, FSH, and estradiol hormones |
| Licorice /Glycyrrhiza glabra/ | – glycyrrhizic acid | – reduces the level of total testosterone – has a strong anti-inflammatory effect |
| Reishi /Ganoderma lucidum/ | – polysaccharides – triterpenes – peptidoglycans | – reduces the activity of the enzyme 5-alpha-reductase – reduces the level of DHT |
| White peony /Paeonia lactiflora/ | – gallic acid – methyl gallate, | – inhibits the production of testosterone – promotes aromatase activity |
| Black cohosh /Actaea racemosa/ | – triterpene glycosides (including actin) – resins (e.g. cimicifugine) – organic acids (caffeic, ferulic, isoferulic and fucinoleic) – cinnamic acid esters – alkaloids (cytisine, methylocytisine) – tannins; isoflavonoids (formononetin) | – stimulates the production of estrogens – anti-inflammatory |
| Nettle /Urtica dioica/ | – flavonoids – tannins – ortho-diphenol – flavonol | – improves the activity of catalase, superoxide dismutase, glutathione peroxidase and malondialdehyde, showing strong antioxidant and anti-inflammatory effects |
| Red ginseng extract /Panax ginseng/ | – ginsenosides | – increasing the proliferation of hair papilla cells by activating: * Wnt/β-catenin, Shh/Gli, AKT/GDP pathways * growth factors VEGF (vascular endothelial growth factor) and EGF (growth factors) – increasing the proliferation of hair papilla cells by inhibiting: * transforming growth factor TGF-β1 * apoptosis (programmed cell death) * the 5-alpha- reductase enzyme |
| Horsetail /Equisetum arvense/ | – silicon | – silicon penetrates the hair follicles, penetrates the hair matrix and thickens the hair fibers. The more silicon in the hair, the less hair loss |
| Chamomile oil /Matricaria chamomilla oil/ | – sesquiterpene compounds, i.e. azulene, bisabolol and farnesene | – supports hair growth by inhibiting the transforming growth factor β1 (TGF-β1), which stimulates the catagen phase in the hair growth cycle – has strong anti-inflammatory properties |
| Pepper /Capsicum annuum L./ | – capsaicin | |
| AnaGain™ organic pea sprouts /Pisum sativum/ | – albumin – polyphenol | – prolongs anagen (the life cycle of hair) – AnaGain™ stimulates specific signal molecules in the dermal papilla required to reactivate hair growth – reduces hair loss – improves hair quality (fuller and thicker hair) |
| NaturSYN™ Beaulixir® complex: linseed oil /Linum usitatissimum/, borage oil /Borago officinalis/, wheat germ oil /Triticum vulgare/, saw palmetto oil /Serenoa repens/, pine phytosterols, rye | – saturated and unsaturated fatty acids – phytosterols – lignans | – inhibits hair follicle miniaturization via inhibiting total 5α-reductase similar to finasteride |
| NcPA extract from soybeans /Glycine max/ | – isoflavones including genistein and daidzein – proteins – vitamins & minerals | – increases hair growth and maintenance via stimulating the proliferation of papilla cells and up-regulating several growth factor mRNA expressions. |
The plant extracts presented above have documented effects in inhibiting miniaturization and/or stimulating hair growth. However, using them on your own can be dangerous. Some of these active ingredients affect the regulation of hormone levels, which means that when used incorrectly, they can interfere with the proper functioning of the endocrine system.
If you are struggling with androgenetic alopecia, the best solution will be to visit a specialist. During such a visit, a trichoscopic analysis is performed, and a detailed interview is conducted. On their basis, a complete therapy is created, which will bring much more benefits than accidentally applied medicals.
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