Regeneration of Hair Follicles Is Modulated by Flightless I (Flii) in a Rodent Vibrissa Model

In the 2011 study, researchers found that Flightless I (Flii), known as a negative regulator of wound healing, plays a positive role in hair follicle regeneration in a rodent vibrissa model. The study compared hair follicle regeneration in rats and mice with low (Flii+/-), normal (Flii+/+), and high (FLIITT) Flii expression levels. Results showed that Flii deficiency (Flii+/-) led to impaired or delayed hair follicle regeneration, while overexpression (FLIITT) resulted in significantly longer terminal hair fibers. The study involved 22 Flii+/- mice, 14 Flii+/+ mice, and 10 FLIITT mice in regeneration rate experiments, and 15 hair follicles from 5 FLIITT mice, 18 hair follicles from 4 Flii+/- mice, and 7 hair follicles from 3 wild-type mice for analyzing hair fiber lengths. The findings suggest that Flii has a complex role in tissue regeneration, with potential implications for regenerative medicine and scar reduction, although the exact mechanisms remain to be clarified.