Topical retinoids and cutaneous biology

In vivo long‐term effects of retinoic acid exposure in utero on induced hyperplastic epidermal foci in murine skin

“…Retinoic acid (RA), the most biologically active natural metabolite of circulating vitamin A, 1 plays an important role in embryogenesis 1 and is fundamental to maintenance of the differentiation pathway of epithelial tissues 2 . Previous studies have demonstrated that prenatal RA exposure induces earlier epidermal differentiation 3 and a stimulatory effect on cell proliferation of the developing epidermis 3 and hair follicles 4 .…”

In vivo long‐term effects of retinoic acid exposure in utero on induced tumours in adult mouse skin

“…All‐ trans ‐retinoic acid (RA), a natural metabolite of circulating vitamin A (retinol), and its analogues (retinoids), are fundamental in maintaining the normal differentiation pathway of epithelial tissues . They are promising agents in skin cancer prevention, as has already been shown in different animal models, following either topical application or oral administration .…”

“…2 All-trans-retinoic acid (RA), a natural metabolite of circulating vitamin A (retinol), and its analogues (retinoids), are fundamental in maintaining the normal differentiation pathway of epithelial tissues. 3 They are promising agents in skin cancer prevention, as has already been shown in different animal models, following either topical application [4][5][6][7] or oral administration. 8,9 Moreover, studies have shown that RA administered to pregnant mice produces an in vivo effect on the developing skin of the fetus 10,11 and long-term effects on hyperplastic epidermal foci induced by the two-stage chemical carcinogenesis protocol in the adult skin of these offspring.…”

N-retinoyl-D-glucosamine, a new retinoic acid agonist, mediates topical retinoid efficacy with no irritation on photoaged skin

“…[21][22][23][24] Retinoids exert these effects by regulating the expression of tar-get genes in a cell and tissue-context-dependent manner. [25][26][27] At the molecular level, retinoids exert their effects through two families of nuclear receptors, RARs and RXRs. RARs and RXRs, as ligand-dependent transcription factors, regulate gene expression by binding to their promoter regions as RAR-RXR heterodimers or RXR homodimers.…”