Hormonal regulation in male androgenetic alopecia—Sex hormones and beyond: Evidence from recent genetic studies

Abstract

Male-pattern hair loss, also termed androgenetic alopecia (AGA), is a highly prevalent age-related condition that is characterized by a distinct pattern of hair loss from the frontotemporal and vertex regions of the scalp. The phenotype is highly heritable and hormone dependent, with androgens being the recognized critical hormonal factor. Numerous molecular genetic studies have focused on genetic variation in and around the gene that encodes the androgen receptor. More recently, however, the availability of high-throughput molecular genetic methods, novel methods of data analysis and sufficiently large sample sizes have rendered possible the systematic investigation of the contribution of other components of the androgen receptor pathway or hormonal pathways beyond the androgen receptor signalling pathways. Over the past decade, genome-wide association studies of increasingly large cohorts have enabled the genome-wide identification of genetic risk factors for AGA, and yielded unprecedented insights into the underlying pathobiology. The present review discusses some of the most intriguing genetic findings on the relevance of (sex)hormonal signalling in AGA.

Cardiovascular Disease-Associated Skin Conditions

“…Its central etiopathogenic feature is an increased sensitivity of the follicle to dihydrotestosterone; however, both inflammatory and environmental factors have contributed. 82 In the last 20 years, several studies have shown a correlation between MAG and CVR. 83 Early on, small case-control studies showed a higher prevalence of traditional and non-traditional CVR factors like obesity, diabetes, low HDL cholesterol, and cIMT.…”

Telomere Dynamics and Telomerase in the Biology of Hair Follicles and their Stem Cells as a Model for Aging Research

“…The role of androgens in AGA has been extensively studied. Each HF is developmentally programmed to respond to identically secreted and locally synthesized sex steroid signals in a differential, location-dependent manner (Heilmann-Heimbach et al, 2020Pantelireis and Higgins, 2018;Williams et al, 2020). Whereas AGA has not been specifically examined in the context of TL dynamics, the promoter region of the catalytic subunit of human telomerase, that is, hTERT, contains an estrogen response element, and hTERT transcript levels vary in response to estrogen as well as progesterone exposure in a time-dependent manner (Misiti et al, 2000;Wang et al, 2000).…”

Platelet Rich Plasma Hybridized Adipose Transplant (PHAT) for the Treatment of Hair Loss: A Case Series

“…Hair restoration is one of the most technologically developed facets of anti-aging [1]. It combines knowledge of hormonal modulation for hair follicle stimulation [2,3], with genetic factors and novel therapeutics including small molecules, peptides transferosomes and exosomes [4][5][6]. Topical formulations, natural products and oral supplements abound as interventions with mixed data on their usage [4].…”