title: Aging of human epidermis: reversal of aging changes correlates with reversal of keratinocyte fas expression and apoptosis.
abstract: The goal of this study was to determine the role of Fas-mediated apoptosis in human epidermal aging. Epidermal Fas expression and apoptosis are increased in aged human skin. Aging changes of human epidermis, including decreased epidermal thickness and proliferation, are reversed following grafting of human skin to SCID (severe combined immunodeficiency) mice. Skin from aged participants (n = 14; mean 70.7 years), and young participants (n = 14; mean 23.4 years) was grafted to beige SCID mice, and epidermal thickness, proliferation (Ki-67 expression), apoptosis (TUNEL [Tdt-mediated dUTP nick end labeling] reaction below granular layer), and expression of Fas and FasL were determined by histology and immunochemical staining. Aged skin was associated with thinning of the epidermis, decreased epidermal proliferation, a significant increase in apoptosis below the granular layer, and epidermal Fas expression. Engraftment significantly reversed these aging changes, including apoptosis, and Fas expression. Correlation of reversal of aging changes, with decreased epidermal Fas expression and apoptosis, supports a role for Fas-mediated apoptosis in aging of human epidermis.
authors.affiliation: Skin Research Laboratory, The B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, and Flieman Medical Center, Haifa, Israel. gilhar@techunix.technion.ac.il
authors.forename: Amos
authors.initials: A
authors.lastname: Gilhar
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Ullmann
authors.forename: Rachel
authors.initials: R
authors.lastname: Karry
authors.forename: Raya
authors.initials: R
authors.lastname: Shalaginov
authors.forename: Bedia
authors.initials: B
authors.lastname: Assy
authors.forename: Sima
authors.initials: S
authors.lastname: Serafimovich
authors.forename: Richard S
authors.initials: RS
authors.lastname: Kalish
mesh_terms: D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism*; D051379:Mice; D016513:Mice, SCID; D008875:Middle Aged; D012879:Skin Physiological Phenomena; D014183:Transplantation, Heterologous; D019014:fas Receptor / Q000096:biosynthesis* / Q000502:physiology
chemical_list: D019014:fas Receptor