Androgenic alopecia (AGA), the most common type of hair loss, is a progressive hair loss disorder that begins in adolescence or late adolescence. The prevalence of males in my country is about 21.3%, and the prevalence of females is about 6.0%. Although some scholars have proposed guidelines for the diagnosis and treatment of androgenetic alopecia in China in the past, they mainly focus on the diagnosis and medical treatment of AGA, and other treatment options are relatively lacking. In recent years, with the emphasis on AGA treatment, some new treatment options have emerged.
Etiology and Pathogenesis
AGA is a genetically predisposed polygenic recessive disorder. Domestic epidemiological surveys show that 53.3%-63.9% of AGA patients have a family history, and the paternal line is significantly higher than the maternal line. Current whole-genome sequencing and mapping studies have identified several susceptibility genes, but their pathogenic genes have not yet been identified. Current research shows that androgens play a decisive role in the pathogenesis of AGA; other factors including inflammation around the hair follicle, increased life pressure, tension and anxiety, and poor living and eating habits can aggravate the symptoms of AGA. Androgens in men mainly come from testosterone secreted by the testes; androgens in women mainly come from the synthesis of adrenal cortex and a small amount of secretion from ovaries, androgen is mainly androstenediol, which can be metabolized into testosterone and dihydrotestosterone . Although androgens are a key factor in the pathogenesis of AGA, the circulating androgen levels in almost all AGA patients are maintained at normal levels. Studies have shown that the effect of androgens on susceptible hair follicles is increased due to increased androgen receptor gene expression and/or increased expression of type II 5α reductase gene in hair follicles in the alopecia area. For AGA, the dermal component cells of susceptible hair follicles contain a specific type II 5α reductase, which can convert the androgen testosterone circulating to the area in the blood to dihydrotestosterone by binding to the intracellular androgen receptor. Initiating a series of reactions leading to progressive miniaturization of hair follicles and hair loss to baldness.
Clinical Manifestations and Treatment Recommendations
AGA is a type of non-scarring alopecia that usually begins during adolescence and is characterized by progressive thinning of hair diameter, loss of hair density, and alopecia until varying degrees of baldness, usually accompanied by symptoms of increased scalp oil secretion.
PRP Application
The platelet concentration is equivalent to a concentrate of 4-6 times the platelet concentration in whole blood. Once PRP is activated, α granules in platelets will release a large number of growth factors, including platelet-derived growth factor, transforming growth factor-β, insulin-like growth factor, epidermal growth factor and vascular endothelial growth factor, etc. The role of promoting hair follicle growth, but the specific mechanism of action is not fully clear. The usage is to inject PRP locally into the dermis layer of the scalp in the alopecia area, once a month, and continuous injections 3 to 6 times can see a certain effect. Although various clinical studies at home and abroad have preliminarily confirmed that PRP has a certain effect on AGA, there is no uniform standard for the preparation of PRP, so the effective rate of PRP treatment is not uniform, and it can be used as an auxiliary means for AGA treatment at this stage.
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Post time: Aug-02-2022