2022 Volume 13 Issue 2 Pages 87-93
Background: The hair cycle is key to understanding the onset of alopecia. We investigated the effects of culturing human hair follicle-derived keratinocytes (HFK) and human follicle dermal papilla cells (HFDPC) under specific conditions to determine the effects of products secreted by the former on hair-related gene expression in the latter to clarify intercellular signal transduction between the tissues that make up the hair root.
Methods: We measured HFDPC gene expression after addition of cultured HFK supernatant and after co-culture with HFK. We also performed experiments using cultured HFK supernatant from which the exosomes had been removed.
Results: A significant increase in the expression of Wnt gene family member 5A (WNT5A), fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor (VEGF) was observed in the HFDPC cultures to which cultured HFK supernatant was added. Meanwhile, co-culture of HFK and HFDPC revealed a less intense increase in WNT5A and FGF2 expression but a more significant increase in VEGF expression. When we removed the exosomes from the cultured HFK supernatant, we observed decreased expression of WNT5A and FGF2, with increased expression of bone morphogenetic protein-2 (BMP2) and VEGF.
Conclusion: These results suggest that the HFDPC hair cycle-related genes are affected by multiple HFK-derived factors. One of these factors may be the exosomes themselves, which increase expression of genes that promote hair loss. Going forward, it may be possible to develop new therapies for alopecia if we can identify these signal transduction factors and verify their presence and function in animals.
