dihydrotestosteroon

Dihydrotestosterone, commonly abbreviated as DHT, is a potent androgen hormone produced from testosterone by the enzyme 5α-reductase. Although some DHT circulates in the bloodstream, most of its biological effects arise from local production in tissues such as the prostate, skin, and hair follicles, where different 5α-reductase isoforms operate.

DHT binds to the androgen receptor with higher affinity than testosterone, leading to the activation of androgen-responsive genes. This makes DHT particularly influential in tissue-specific development and function. The conversion of testosterone to DHT amplifies androgen signaling in certain organs, contributing to both normal physiology and disease if signaling becomes excessive.

Physiological roles of DHT include fetal development of male external genitalia, initiation of male puberty, and maintenance of certain tissues such as the prostate and sebaceous glands. In adults, DHT helps regulate hair and skin biology. However, elevated DHT signaling in the scalp is associated with androgenetic alopecia, while in the prostate it can contribute to benign prostatic hyperplasia.

Clinical relevance and therapeutics focus on modulating DHT levels. Inhibitors of 5α-reductase, such as finasteride and dutasteride, reduce DHT synthesis and are used to treat benign prostatic hyperplasia and male pattern baldness. Side effects can include sexual dysfunction and mood changes, reflecting the hormone’s broad role in male physiology. In individuals with 5α-reductase deficiency, reduced DHT production can result in undervirilization or ambiguous genitalia.