title: Relationship between NMF (lactate and potassium) content and the physical properties of the stratum corneum in healthy subjects.
abstract: Natural moisturizing factor (NMF) of the stratum corneum (SC) has been established to play important roles in the physical properties of the SC. Few studies, however, have investigated the specific influences of NMF components other than the amino acids. In this study, therefore, we focus on the relationship between the ion content and physical properties of the SC in 40 healthy subjects. Changes in the physical properties of the SC induced by the extraction of NMF were equivalent to the changes that took place from summer to winter, demonstrating the important role of NMF in the physical properties of the SC in healthy subjects. The seasonal changes in the physical properties of the SC from summer to winter were accompanied by significant decreases in the levels of lactate, potassium, sodium, and chloride in the SC. Lactate and potassium were the only components found to correlate significantly with the state of hydration, stiffness, and pH in the SC. Interestingly, the levels of lactate and potassium in the SC were also significantly correlated. Moreover, potassium lactate restored the SC hydration state decreased by extraction of NMF. These results suggest that lactate and potassium may play roles in maintaining the physical properties of the SC in healthy subjects.
authors.affiliation: Basic Research Laboratory, Kanagawa-ken, Japan. noriaki@oda.cos.kanebo.co.jp
authors.forename: Noriaki
authors.initials: N
authors.lastname: Nakagawa
authors.forename: Shingo
authors.initials: S
authors.lastname: Sakai
authors.forename: Masayuki
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yamada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nagano
authors.forename: Takuo
authors.initials: T
authors.lastname: Yuki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sumida
authors.forename: Hideyo
authors.initials: H
authors.lastname: Uchiwa
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000032:analysis; D004817:Epidermis / Q000737:chemistry*; D006801:Humans; D019344:Lactic Acid / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000032:analysis* / Q000502:physiology; D012621:Seasons; D012964:Sodium / Q000032:analysis; D013542:Sweat / Q000737:chemistry; D014867:Water
chemical_list: D000596:Amino Acids; D014867:Water; D019344:Lactic Acid; D012964:Sodium; D011188:Potassium