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Evidence for Involvement of Nonclassical Pathways in the Protection From UV-Induced DNA Damage by Vitamin D-Related
Warusavithana Gunawardena Manori De Silva1, Jeremy Zhuo Ru Han1, Chen Yang1
1Physiology, School of Medical Sciences and Bosch Institute University of Sydney Sydney NSW Australia.
JBMR Plus
|December 24, 2021
Summary
Vitamin D compounds protect skin from UV damage by reducing DNA lesions. This photoprotective effect requires the vitamin D receptor and impacts cellular respiration and CREB phosphorylation, suggesting an anti-cancer role.
Area of Science:
- Dermatology
- Endocrinology
- Molecular Biology
Background:
- The hormone 1,25dihydroxyvitamin D3 (1,25(OH)2D3) and related compounds protect skin from UV-induced DNA damage.
- These protective effects involve reducing cyclobutane pyrimidine dimers (CPD) and oxidative damage (8-oxo-7,8-dihydro-2'-deoxyguanosine).
Purpose of the Study:
- To investigate the role of the vitamin D receptor (VDR) and ERp57 in the photoprotective mechanisms of vitamin D-related compounds.
- To explore the cellular effects of 1,25(OH)2D3, including oxygen consumption and CREB phosphorylation, in human keratinocytes exposed to UV radiation.
Main Methods:
- Small interfering RNA (siRNA) was used to knockdown the vitamin D receptor and ERp57.
- Human keratinocytes were treated with vitamin D compounds and exposed to UV irradiation.
- Oxygen consumption rates and CREB phosphorylation were measured.
Main Results:
- Knockdown of VDR or ERp57 abolished the reduction in UV-induced DNA damage by 20-hydroxyvitamin D3 or 24-hydroxylumisterol3.
- 1,25(OH)2D3 treatment reduced oxygen consumption and CREB phosphorylation in UV-exposed keratinocytes.
- These cellular changes are known to inhibit skin carcinogenesis.
Conclusions:
- The vitamin D receptor is essential for the photoprotective effects of 1,25(OH)2D3 and CYP11A1-derived vitamin D compounds.
- The observed cellular effects of 1,25(OH)2D3 are consistent with its previously established anticarcinogenic activity.
- VDR's role in photoprotection may explain differential susceptibility to UV-induced skin cancers in mice lacking VDR or 1α-hydroxylase.
Keywords:
1α,25‐DIHYDROXYVITAMIN D3CREB PHOSPHORYLATIONERp57LUMISTEROLOXIDATIVE PHOSPHORYLATIONUV‐INDUCED DNA DAMAGEVITAMIN D RECEPTORMore Related Videos
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