title: Aged keratinocyte phenotyping: morphology, biochemical markers and effects of Dead Sea minerals.
abstract: The aging process and its characterization in keratinocytes have not been studied in depth until now. We have assessed the cellular and molecular characteristics of aged epidermal keratinocytes in monolayer cultures and in skin by measuring their morphological, fluorometric and biochemical properties. Light and electron microscopy, as well as flow cytometry, revealed increase in cell size, changes in cell shape, alterations in mitochondrial structure and cytoplasmic content with aging. We showed that the expression of 16 biochemical markers was altered in aged cultured cells and in tissues, including caspases 1 and 3 and beta-galactosidase activities, immunoreactivities of p16, Ki67, 20S proteasome and effectors of the Fas-dependent apoptotic pathway. Aged cells diversity, and individual variability of aging markers, call for a multifunctional assessment of the aging phenomenon, and of its modulation by drugs. As a test case, we have measured the effects of Dead Sea minerals on keratinocyte cultures and human skin, and found that they stimulate proliferation and mitochondrial activity, decrease the expression of some aging markers, and limit apoptotic damage after UVB irradiation.
authors.affiliation: Myers Laboratory of Skin Biology and Biochemistry, Department of Biological Chemistry, The Hebrew University of Jerusalem at Givat Ram, Jerusalem 91904, Israel.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Soroka
authors.forename: Zeev
authors.initials: Z
authors.lastname: Ma'or
authors.forename: Yael
authors.initials: Y
authors.lastname: Leshem
authors.forename: Lilian
authors.initials: L
authors.lastname: Verochovsky
authors.forename: Rami
authors.initials: R
authors.lastname: Neuman
authors.forename: François Menahem
authors.initials: FM
authors.lastname: Brégégère
authors.forename: Yoram
authors.initials: Y
authors.lastname: Milner