title: The thinning top: why old people have less hair.
abstract: Changes in the hair cycle underlie age-related alopecia, but the causative mechanisms have remained unclear. Chen et al. point to an imbalance between stem cell-activating and -inhibitory signals as the key determinant of age-related regenerative decline. Further, they identify a secreted protein, follistatin, that may be able to shift the balance toward renewal.
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Department of Plastic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Sashank K
authors.initials: SK
authors.lastname: Reddy
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. Electronic address: LAG@jhmi.edu.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Garza
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D038681:Follistatin / Q000502:physiology*; D018859:Hair Follicle / Q000502:physiology*; D036341:Intercellular Signaling Peptides and Proteins / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D012038:Regeneration / Q000502:physiology*; D000094742:Secreted Frizzled-Related Proteins
chemical_list: D038681:Follistatin; D036341:Intercellular Signaling Peptides and Proteins; D011518:Proto-Oncogene Proteins; C501127:Dkk1 protein, mouse; C498454:Sfrp4 protein, mouse; D000094742:Secreted Frizzled-Related Proteins