Female pattern hair loss (FPHL) is a non-scarring form of alopecia, resulting from premature catagen induction leading to telogen effluvium and progressive transformation of terminal (t) scalp hair follicles (HFs) into intermediate/miniaturized (i/m) HFs. Currently available treatment strategies, are often combined with nutritional supplements. However, data supporting nutrient deficiency in FPHL HFs are lacking.Therefore, we attempted to investigate this by asking whether any changes can be seen in perifollicular vascularization in FPHL and by examining HF nutritional status and metabolism in affected and non-affected HFs. CD31 quantification revealed significantly reduced numbers of perifollicular blood vessels in the relatively unaffected (occipital) but most prominently in the affected (parietal) scalp from FPHL patients compared to occipital scalp from healthy donors. This was accompanied by changes in the interfollicular expression of angiogenesis-associated growth factors VEGF and thrombospondin-1. Metabolic analyses showed that nutrients important for adequate hair growth such as biotin, pantothenic acid, L-cysteine, and L-glutamic acid were decreased in iHFs compared to tHFs in affected FPHL scalp skin. iHFs also displayed a more quiescent metabolic phenotype, characterized by a lower rate of aerobic glycolysis and glutaminolysis during organ culture. Yet, lesional t or i/m FPHL HFs were capable of taking up labelled exogenous nutrients when these were added in excess into the organ culture medium.Taken together, our data suggest that t and i/m HFs in FPHL affected scalp skin are poorly vascularized which likely compromises nutrient delivery to the HFs and that nutrient supplementation may be capable in principle to correct this deficiency.

ESDR333 - Poor perifollicular vascularization is associated with nutrient insufficiency and a quiescent metabolic phenotype in intermediate hair follicles from patients with female pattern hair loss

50th Annual Meeting of the European Society for Dermatological Research. VIRTUAL MEETING