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Updated: May 11, 2026

Cultivating a Three-dimensional Reconstructed Human Epidermis at a Large Scale
Published on: May 28, 2021
[Epidermal thickness and keratinocyte proliferation after cutaneous application of vitamin D]
S A Zhuchkov1, T A Belousova, V I Nosdrin
1Medical Institute of Oryol State University, Oryol, Russia
Abstract:
Using light microscopy, morphometry and immunohistochemistry, the epidermis of 72 male and female rats was examined 1 day and 1 month after the completion of daily cutaneous applications of vitamin D3-containing composition lasting for two weeks. It was found that vitamin D3 causes a statistically significant reduction in the thickness of interfollicular epidermis and in the number of Ki-67 positive keratinocytes. The identified effects persisted for 1 month after the last application of the preparation. Modifying influence of vitamin D3 on the morphogenetic processes in the epidermis, which were manifested, in particular, by a decreased proliferative activity of keratinocytes, is discussed in the light of the data on the possibility of the formation of its active metabolite--calcitriol--directly in the skin.
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