Effect of dehydrotestosterone blockers in androgenic alopecia
Pro Research Analysisby 
Searched over 200M research papers
Consensus Meter
Effect of Dehydrotestosterone Blockers in Androgenic Alopecia
Introduction to Androgenic Alopecia and Dihydrotestosterone
Androgenic alopecia (AGA), commonly known as male pattern baldness, is a prevalent form of hair loss affecting millions worldwide. The primary androgen implicated in AGA is dihydrotestosterone (DHT), which is derived from testosterone through the action of the enzyme 5-alpha reductase (5AR) . Elevated levels of DHT in the scalp lead to the miniaturization of hair follicles, resulting in progressive hair thinning and loss .
Mechanism of Action of DHT in Hair Follicles
DHT exerts its effects by binding to androgen receptors in hair follicles, leading to early hair regression, miniaturization, and density loss. This process has been demonstrated in animal models, where DHT activation of androgen receptors in C57BL/6 mice resulted in significant hair loss, which could be partially reversed by the AR antagonist bicalutamide.
5-Alpha Reductase Inhibitors: Finasteride and Dutasteride
Finasteride
Finasteride is a type II 5-alpha reductase inhibitor that reduces the conversion of testosterone to DHT, thereby lowering DHT levels in the scalp and serum . Clinical trials have shown that finasteride significantly improves hair count and slows hair loss in men with AGA over a period of two years. The drug's efficacy is supported by its ability to decrease scalp DHT levels by up to 69.4% and serum DHT levels by up to 72.2%. Additionally, finasteride has been associated with up-regulation of insulin-like growth factor 1 (IGF-1) in dermal papilla cells, which correlates with clinical improvement in hair growth.
Dutasteride
Dutasteride, a dual 5-alpha reductase inhibitor, blocks both type I and type II isoenzymes, making it more potent than finasteride . Studies have demonstrated that dutasteride significantly increases hair count and width, showing superior efficacy compared to finasteride and placebo. In a randomized trial, dutasteride 0.5 mg daily was found to be particularly effective, with significant improvements in hair growth and restoration observed within 24 weeks. Dutasteride has also shown promise in treating female AGA, with significant clinical improvement noted in a case study.
Alternative Treatments: Botanical 5-Alpha Reductase Inhibitors
Botanically derived 5-alpha reductase inhibitors, such as the liposterolic extract of Serenoa repens (LSESr) and beta-sitosterol, have also been explored for their efficacy in treating AGA. A placebo-controlled, double-blind study reported a positive response in 60% of subjects treated with these botanical compounds, suggesting their potential as alternative treatments for AGA.
Emerging Therapies: Mesenchymal Stromal Cell-Derived Exosomes
Recent research has highlighted the potential of adipose mesenchymal stromal cell-derived exosomes (ADSC-Exos) in counteracting the inhibitory effects of DHT on hair follicles. ADSC-Exos carrying miR-122-5p have been shown to promote hair follicle regeneration by targeting the TGF-β1/SMAD3 signaling pathway, offering a novel therapeutic approach for AGA.
Conclusion
The use of DHT blockers, particularly 5-alpha reductase inhibitors like finasteride and dutasteride, has proven effective in treating androgenic alopecia by reducing DHT levels and promoting hair regrowth. Emerging therapies, including botanical inhibitors and mesenchymal stromal cell-derived exosomes, offer promising alternatives and advancements in the treatment of AGA. Continued research and clinical trials are essential to further understand and enhance these treatment modalities.
Sources and full results
Most relevant research papers on this topic