Abstract

A REVIEW ARTICAL ON MALE ANDROGENETIC ALOPECIA (MAA) & ANDROGENS ATTACK ON HAIR.

Praveen Kumar Paswan*, Nidhi Patel, Bhumika Parmar, Devanshi Sharma and Abhi Depani

ABSTRACT

Different hormones have a significant impact on the hair cycle and the development of the hair follicle. The main contributors to terminal hair development are androgens like testosterone (T), dihydrotestosterone (DHT), an their prohormones dehydroepiandrosterone sulphate (DHEAS) and androstendione (A). Small, straight, fair vellus hairs on sex-specific body parts are transformed into larger, darker terminal hairs by their action. They bind to intracellular androgen receptors found in the hair follicle's dermal papilla cells. The intracellular enzyme 5-alpha reductase is also necessary for the majority of hair follicles to convert testosterone into DHT. The effect of other hormones, besides androgens, is also currently being studied. Male androgenetic alopecia (MAA) is the most common form of hair loss in men, affecting 30-50% of men by age 50. MAA occurs in a highly reproducible pattern, preferentially affecting the temples, vertex and mid frontal scalp. Although MAA is often regarded as a relatively minor dermatological condition, hair loss impacts self-image and is a great cause of anxiety and depression in some men. MAA is increasingly identified as a risk factor for arterial stiffness and cardiovascular disease. A familial tendency to MAA and racial variation in the prevalence is well recognized, with heredity accounting for approximately 80% of predisposition. Normal levels of androgens are sufficient to cause hair loss in genetically susceptible individuals. The key pathophysiological features of MAA are alteration in hair cycle development, follicular miniaturization, and inflammation. In MAA, the anagen phase decreases with each cycle, while the length of telogen remains constant or is prolonged. Ultimately, anagen duration becomes so short that the growing hair fails to achieve sufficient length to reach the surface of the skin, leaving an empty follicular pore. Hair follicle miniaturization is the histological hallmark of androgenetic alopecia. Once the arrector pili muscle, that attaches circumferentially around the primary follicle, has detached from all secondary follicles and primary follicles have undergone miniaturization and detachment, hair loss is likely irreversible. While many men choose not to undergo treatment, topical minoxidil and oral finasteride are approved by the Food and Drug Administration (USA) for the treatment of MAA.

Keywords: hormones, hair follicle, hair growth, Male androgenetic alopecia (MAA).