Androgens Modulate Keratinocyte Differentiation Indirectly Through Enhancing Growth Factor Production From Dermal Fibroblasts

The study from March 1, 2019, investigated the role of androgens in the abnormal keratinization of the hair infundibulum, a key factor in the pathogenesis of acne vulgaris. The researchers hypothesized that androgens affect dermal fibroblasts, leading to changes in keratinocyte differentiation through the production of growth factors. They conducted in vitro experiments on human fibroblasts and keratinocytes, both separately and in co-culture, and in vivo studies on acne lesions and normal facial skin. The results showed that androgens significantly increased the expression of amphiregulin (AREG), epiregulin (EREG), fibroblast growth factor (FGF) 10, and insulin-like growth factor binding protein (IGFBP) 5 in human fibroblasts but not in keratinocytes. In acne lesions, these growth factors were more abundant compared to normal skin. FGF10, in particular, was found to suppress the expression of cytokeratin 1 and 10 in keratinocytes, which was consistent with the decreased ratio of these proteins in acne lesions. The study concluded that androgens modulate keratinocyte differentiation indirectly by enhancing growth factor production from dermal fibroblasts, which then affects the keratinocytes.