Can Antibiotic-Induced Changes in the Composition of the Hair Follicle Microbiome Regulate Human Hair Growth?

This document presents preliminary results from a pilot study investigating whether antibiotics can influence human hair growth by altering the hair follicle microbiome. The study involved treating anagen hair follicles with ceftriaxone (CTX) or roxithromycin (RXM) and then culturing them. RXM treatment, but not CTX, tendentially increased hair shaft production and the percentage of hair follicles in the anagen phase, with substantial inter-individual differences. RXM also promoted the growth of certain bacteria like Propionibacteriaceae while reducing others like Staphylococcus. However, there was no significant change in intrafollicular protein expression of the anagen-promoting growth factor IGF-1 or dermal papilla inductivity. The study suggests that antibiotics may impact hair growth and hair matrix proliferation by altering the hair follicle microbiome, but further research is needed to confirm these findings and understand the mechanisms involved. The sample size for the RXM group was n=5 hair follicles, while the PBS and CTX groups had n=8 hair follicles each.