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Updated: Aug 9, 2026
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Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin
Published on: July 14, 2017
PUVA downregulates whn expression in primary mouse keratinocytes
C Alge1, R M Baxter, M E Doyle
1Wellman Laboratories of Photomedicine, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, WEL 224, 55 Fruit Street, Boston, MA 02114, USA.
Journal of Photochemistry and Photobiology. B, Biology
|November 14, 2001
Summary
Psoralen photochemotherapy (PUVA) effectively treats psoriasis by down-regulating the whn gene in skin cells. This gene suppression may explain PUVA's anti-proliferative effects on keratinocytes.
Area of Science:
- Dermatology
- Molecular Biology
- Photobiology
Background:
- Psoralen photochemotherapy (PUVA) is a primary treatment for psoriasis.
- The whn gene (nude gene) is crucial for epidermal homeostasis.
- Overexpression of whn in epidermis can lead to a psoriasis-like phenotype.
Purpose of the Study:
- To investigate the specific effects of PUVA on keratinocyte whn expression.
- To determine if whn suppression mediates PUVA's therapeutic action.
Main Methods:
- Treatment of animals with PUVA and UVA alone.
- Analysis of whn mRNA levels and promoter activity.
- Assessment of DNA synthesis in whn-null and wild-type keratinocytes.
Main Results:
- PUVA, but not UVA alone, caused persistent down-regulation of whn mRNA 48-72 hours post-treatment.
- A dose-dependent down-regulation of whn promoter activity was observed with PUVA.
- whn-null keratinocytes showed increased resistance to PUVA-induced suppression of DNA synthesis compared to wild-type cells.
Conclusions:
- PUVA treatment leads to sustained suppression of whn expression in keratinocytes.
- whn suppression is implicated in the anti-proliferative effects of PUVA on skin cells.
- Findings suggest a molecular mechanism for PUVA's efficacy in treating skin conditions like psoriasis.
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