title: Aging enhances maceration-induced ultrastructural alteration of the epidermis and impairment of skin barrier function.
abstract: BACKGROUND
  Skin maceration is recognized as a risk factor for the development of certain skin lesions. In health care settings, incontinence-associated skin maceration is highly prevalent in the elderly. However, the effect of senescence on maceration has not been fully elucidated.
  
  
  OBJECTIVE
  To reveal the enhancement of the maceration-induced ultrastructural alteration and barrier function of the epidermis by aging.
  
  
  METHODS
  Skin maceration was reproduced by exposure to agarose gel in human and rat. The ultrastructural alterations in human and rat tissue were observed by transmission electron microscopy. The skin barrier function was evaluated by noninvasive methods in human, and by the transdermal penetration of small- and large-fluorescent molecules in rat. In order to reveal the effect of aging on the skin maceration, we compared these parameters between young and aged rats.
  
  
  RESULTS
  In macerated skin, we observed expansion of the interstices of the stratum corneum, spinosum, and basale of the epidermis; disruption of the intercellular lipid structure in the stratum corneum; a decreased number of cell processes in the stratum spinosum and basale. The transdermal penetration test in the rat using two types of fluorescein indicated that maceration disrupted skin barrier function. Furthermore, senescence-enhanced ultrastructural and functional alterations were revealed in the rodent studies.
  
  
  CONCLUSIONS
  This study demonstrates that aging enhances skin maceration. Considering that maceration is a risk factor for the skin damage, the development of technology to promote skin barrier recovery after maceration in the elderly is warranted.
authors.affiliation: Department of Advanced Skin Care, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. tminematsu-tky@umin.ac.jp
authors.forename: Takeo
authors.initials: T
authors.lastname: Minematsu
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagase
authors.forename: Ayumi
authors.initials: A
authors.lastname: Naito
authors.forename: Kimie
authors.initials: K
authors.lastname: Takehara
authors.forename: Shinji
authors.initials: S
authors.lastname: Iizaka
authors.forename: Kazunori
authors.initials: K
authors.lastname: Komagata
authors.forename: Lijuan
authors.initials: L
authors.lastname: Huang
authors.forename: Gojiro
authors.initials: G
authors.lastname: Nakagami
authors.forename: Tomoko
authors.initials: T
authors.lastname: Akase
authors.forename: Makoto
authors.initials: M
authors.lastname: Oe
authors.forename: Kotaro
authors.initials: K
authors.lastname: Yoshimura
authors.forename: Tadao
authors.initials: T
authors.lastname: Ishizuka
authors.forename: Junko
authors.initials: J
authors.lastname: Sugama
authors.forename: Hiromi
authors.initials: H
authors.lastname: Sanada
mesh_terms: D000328:Adult; D000367:Age Factors; D000818:Animals; D016922:Cellular Senescence; D004817:Epidermis / Q000378:metabolism* / Q000648:ultrastructure*; D005260:Female; D019793:Fluorescein / Q000494:pharmacology; D005456:Fluorescent Dyes / Q000494:pharmacology; D006801:Humans; D008055:Lipids / Q000737:chemistry; D008297:Male; D046529:Microscopy, Electron, Transmission / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012307:Risk Factors; D015595:Skin Aging; D012871:Skin Diseases / Q000378:metabolism*; D012879:Skin Physiological Phenomena
chemical_list: D005456:Fluorescent Dyes; D008055:Lipids; D019793:Fluorescein