Control of pelage hair follicle development and cycling by complex interactions between follistatin and activin

The document from 2003 explores the interaction between follistatin and activin, both part of the TGF-ß/BMP family, in the development and cycling of hair follicles (HFs) in mice. It was discovered that follistatin promotes HF development and cycling, while activin inhibits these processes. Follistatin knockout mice and activin ßA transgenic mice both exhibited delayed HF morphogenesis and altered hair cycle phases. In vitro experiments showed that follistatin can stimulate HF development, an effect that is counteracted by activin A. The study also found that activin affects HF cycling by modulating BMP-2 and its inhibitor MGP. These findings suggest that follistatin and activin play crucial roles in HF development and cycling, potentially offering targets for treating hair growth disorders. However, the study did not specify the number of mice used in each experimental group.