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Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin
Published on: July 14, 2017
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Calcitriol modulates epidermal tight junction barrier function in human keratinocytes
Juan Valentin Trujillo-Paez1, Ge Peng2, Hai Le Thanh Nguyen2
1Atopy (Allergy) Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
Journal of Dermatological Science
|March 6, 2024
Summary
Calcitriol enhances skin barrier function by increasing tight junction proteins in keratinocytes. This vitamin D metabolite supports skin homeostasis and may help treat barrier-impaired diseases.
Area of Science:
- Dermatology
- Cell Biology
- Molecular Biology
Background:
- Aberrant expression of tight junction (TJ) proteins is linked to skin barrier diseases like atopic dermatitis and psoriasis.
- Calcitriol is known to play a role in skin homeostasis, but its effect on skin barrier function is unclear.
Purpose of the Study:
- To investigate the impact of calcitriol on TJ barrier function in human primary keratinocytes.
Main Methods:
- Human primary keratinocytes were treated with calcitriol.
- TJ protein expression was analyzed using real-time PCR and Western blotting.
- Immunofluorescence and transepithelial electrical resistance (TER) assays assessed TJ distribution and barrier function.
Main Results:
- Calcitriol significantly increased the expression of TJ proteins (claudin-4, claudin-7, occludin, ZO-1).
- It improved TJ protein distribution at cell borders and activated key signaling pathways (aPKC, Rac1, PI3K, Akt).
- Calcitriol treatment enhanced TER in keratinocyte monolayers, indicating improved barrier function.
Conclusions:
- Calcitriol modulates the expression of keratinocyte TJ proteins.
- This action contributes to maintaining normal skin barrier function.
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