The aged epidermal permeability barrier: basis for functional abnormalities.
Aged epidermis develops an abnormality in permeability barrier homeostasis, which is accentuated further in photoaged skin. The biochemical basis is a global reduction in stratum corneum lipids and profound abnormality in cholesterol synthesis. Various cytokine/growth factor signaling pathways are abnormal in aged skin, particularly in the interleukin-1 family. Barrier repair therapy can be effective in restoring normal function if a cholesterol-dominant mixture of the three key physiologic lipids, including ceramides and free fatty acids, is emphasized.
Elias
Peter M
PM
Department of Dermatology, University of California, San Francisco, USA. eliaspm@itsa.ucsf.edu
Ghadially
Ruby
R
D000368:Aged; D000375:Aging / Q000502:physiology; D022762:CCAAT-Enhancer-Binding Proteins / Q000502:physiology; D002463:Cell Membrane Permeability; D004268:DNA-Binding Proteins / Q000502:physiology; D004815:Epidermal Growth Factor / Q000502:physiology; D004817:Epidermis / Q000502:physiology*; D006801:Humans; D007375:Interleukin-1 / Q000502:physiology; D015595:Skin Aging / Q000502:physiology; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors / Q000502:physiology
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D007375:Interleukin-1; C497387:SREBF1 protein, human; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors; D004815:Epidermal Growth Factor