title: Kinetin Improves Barrier Function of the Skin by Modulating Keratinocyte Differentiation Markers.
abstract: BACKGROUND
  Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier.
  
  
  OBJECTIVE
  We examined whether kinetin induces skin barrier functionsin vitroandin vivo.
  
  
  METHODS
  To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers was assessed. Moreover, we examined the clinical efficacy of kinetin by evaluating skin moisture, transepidermal water loss (TEWL), and skin surface roughness in patients who used kinetin-containing cream. We performed quantitative real-time polymerase chain reaction to measure the expression of keratinocyte differentiation markers in HaCaT cells following treatment. A clinical trial was performed to assess skin moisture, TEWL, and evenness of skin texture in subjects who used kinetin-containing cream for 4 weeks.
  
  
  RESULTS
  Kinetin increased involucrin, and keratin 1 mRNA in HaCaT cells. Moreover, use of a kinetin-containing cream improved skin moisture and TEWL while decreasing roughness of skin texture.
  
  
  CONCLUSIONS
  Kinetin induced the expression of keratinocyte differentiation markers, suggesting that it may affect differentiation to improve skin moisture content, TEWL, and other signs of skin aging. Therefore, kinetin is a potential new component for use in cosmetics as an anti-aging agent that improves the barrier function of skin.
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Sungkwan
authors.initials: S
authors.lastname: An
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Hwa Jun
authors.initials: HJ
authors.lastname: Cha
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Ko
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Hyunjoo
authors.initials: H
authors.lastname: Han
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Su Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Kyung-Suk
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Song Jeong
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: KISCS Incorporated, Cheongju, Korea.
authors.forename: In-Sook
authors.initials: IS
authors.lastname: An
authors.affiliation: Orangewood Christian School, Maitland, FL, USA.
authors.forename: Sangwon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Dermatology, Konkuk University School of Medicine, Seoul, Korea.
authors.forename: Hae Jeong
authors.initials: HJ
authors.lastname: Youn
authors.affiliation: Department of Dermatology, Konkuk University School of Medicine, Seoul, Korea.
authors.forename: Kyu Joong
authors.initials: KJ
authors.lastname: Ahn
authors.affiliation: Korea Institute for Skin and Clinical Sciences, Konkuk University, Seoul, Korea.
authors.forename: Soo-Yeon
authors.initials: SY
authors.lastname: Kim
keywords: Cell culture techniques; Differentiation; Keratinocytes; Kinetin; Skin barrier