Clinical Patterns of Hair Loss in Men Is DHT the Only Culprit?

[madman]

INTRODUCTION

The pathophysiology of male androgenetic alopecia (AGA) has focused on the role of androgens, mainly dihydrotestosterone (DHT) and its production by 5a-reductase. Inhibitors of 5a-reductase have been developed and studied for male AGA including finasteride, which was approved by the US Food and Drug Administration for the treatment of male AGA in 1998. Overall, the important role of DHT in the pathophysiology of male AGA and as a therapeutic target has been well-established. However, there is increasing evidence of other important pathways and factors in the development and pathophysiology of male AGA, which are discussed herein.




*OXIDATIVE STRESS

*INFLAMMATION

*PROSTAGLANDINS

*VASCULOGENESIS

*WNT/b-CATENIN AND TRANSFORMING GROWTH FACTOR-b PATHWAYS

*AGING

*LIFESTYLE FACTORS AND COMORBIDITIES




SUMMARY

The role of 5a-reductase activity and DHT and its usefulness as a therapeutic target for male AGA has been well-established. Additionally, a number of other contributing factors and pathways have been investigated and shown to be involved in AGA in men. Further studies of these pathways in how they relate to AGA and how these translate to potential therapeutic options are still needed.

 

[madman]

KEY POINTS

*Pathways and factors, including oxidative stress, inflammation, prostaglandins, vasculogenesis, Wnt/b-catenin, and transforming growth factor-b, have increasingly been shown to be important in the pathophysiology of androgenetic alopecia in men

*There is limited but increasing evidence of the potential safety and efficacy of treatments targeting these pathways for androgenetic alopecia

*Lifestyle factors and comorbidities including cardiovascular risk factors have been shown to be associated with male androgenetic alopecia

*Changes in hair characteristics related to aging, termed senescent alopecia, often coexist with male androgenetic alopecia with advancing age

*Further study of these pathways, risk factors, and comorbidities is important to better understand the pathophysiology, find potentially useful therapeutic targets and ensure a comprehensive approach to the management of androgenetic alopecia in men