Study uncovers new data on how hair regeneration occurs

Los Angeles - The findings of a University of Southern California (USC) stem cell research team may lead to new ways to regulate hair and, ultimately, organ regeneration, Newswise.com reports.

The researchers identified cyclic signaling in the dermis that coordinates stem cell activity and regulates regeneration in the hair of mice. According to the study, published in the Jan. 17 issue of the journal Nature, the signaling switch involves bone morphogenetic protein (Bmp) pathways.

Newswise.com quotes Cheng-Ming Chuong, M.D., Ph.D, principal investigator and professor of pathology at USC’s Keck School of Medicine, as saying, “Conceptually, the findings have important implications for stem cell research and in understanding how stem cell activity is regulated during regeneration. The research presents a new dimension for the regulation of hair regrowth and, ultimately, organ regeneration.”

The study notes that while recent studies have found that hair cycling is one of the mainstream models for organ regeneration, most research focuses on the cyclic regeneration of one hair follicle. The USC researcher team found that hairs in normal mice regenerate in waves, rather than individually, which suggests that hair stem cells are regulated not only by the micro-environment within a single hair follicle - as has previously been thought - but also by adjacent follicles, other skin compartments and systemic hormones.

The findings also suggest that periodic expression of Bmp in the skin macro-environment is at the center of the mechanism for coordinated hair stem cell activation. When many hairs regenerate, they must communicate activation signals among themselves. At different points in time, the study says, the macro-environment can be either permissive or suppressive for stem cell activation.

The study was funded by the National Institutes of Arthritis, Musculoskeletal and Skin Diseases, the National Institute of Aging, the California Institute for Regenerative Medicine and the Research Councils U.K.