Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (2)

Search Parameters:
Authors = Wayne G. Wamer

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
6 pages, 280 KiB  
Article
Photoirradiation of Retinyl Palmitate in Ethanol with Ultraviolet Light - Formation of Photodecomposition Products, Reactive Oxygen Species, and Lipid Peroxides
by Qingsu Xia, Jun J. Yin, Wayne G. Wamer, Shu-Hui Cherng, Mary D. Boudreau, Paul C. Howard, Hongtao Yu and Peter P. Fu
Int. J. Environ. Res. Public Health 2006, 3(2), 185-190; https://doi.org/10.3390/ijerph2006030021 - 30 Jun 2006
Cited by 28 | Viewed by 14735
Abstract
We have previously reported that photoirradiation of retinyl palmitate (RP), a storage and ester form of vitamin A (retinol), with UVA light resulted in the formation of photodecomposition products, generation of reactive oxygen species, and induction of lipid peroxidation. In this paper, we [...] Read more.
We have previously reported that photoirradiation of retinyl palmitate (RP), a storage and ester form of vitamin A (retinol), with UVA light resulted in the formation of photodecomposition products, generation of reactive oxygen species, and induction of lipid peroxidation. In this paper, we report our results following the photoirradiation of RP in ethanol by an UV lamp with approximately equal UVA and UVB light. The photodecomposition products were separated by reversed-phase HPLC and characterized spectroscopically by comparison with authentic standards. The identified products include: 4-keto-RP, 11-ethoxy-12-hydroxy-RP, 13-ethoxy-14-hydroxy-RP, anhydroretinol (AR), and trans- and cis-15-ethoxy-AR. Photoirradiation of RP in the presence of a lipid, methyl linoleate, resulted in induction of lipid peroxidation. Lipid peroxidation was inhibited when sodium azide was present during photoirradiation which suggests free radicals were formed. Our results demonstrate that, similar to irradiation with UVA light, RP can act as a photosensitizer leading to free radical formation and induction of lipid peroxidation following irradiation with UVB light. Full article
Show Figures

9 pages, 416 KiB  
Article
Photodecomposition and Phototoxicity of Natural Retinoids
by William H. Tolleson, Shui-Hui Cherng, Qingsu Xia, Mary Boudreau, Jun Jie Yin, Wayne G. Wamer, Paul C. Howard, Hongtao Yu and Peter P. Fu
Int. J. Environ. Res. Public Health 2005, 2(1), 147-155; https://doi.org/10.3390/ijerph2005010147 - 30 Apr 2005
Cited by 63 | Viewed by 18429
Abstract
Sunlight is a known human carcinogen. Many cosmetics contain retinoid-based compounds, such as retinyl palmitate (RP), either to protect the skin or to stimulate skin responses that will correct skin damaged by sunlight. However, little is known about the photodecomposition of some retinoids [...] Read more.
Sunlight is a known human carcinogen. Many cosmetics contain retinoid-based compounds, such as retinyl palmitate (RP), either to protect the skin or to stimulate skin responses that will correct skin damaged by sunlight. However, little is known about the photodecomposition of some retinoids and the toxicity of these retinoids and their sunlight-induced photodecomposition products on skin. Thus, studies are required to test whether topical application of retinoids enhances the phototoxicity and photocarcinogenicity of sunlight and UV light. Mechanistic studies are needed to provide insight into the disposition of retinoids in vitro and on the skin, and to test thoroughly whether genotoxic damage by UV-induced radicals may participate in any toxicity of topically applied retinoids in the presence of UV light. This paper reports the update information and our experimental results on photostability, photoreactions, and phototoxicity of the natural retinoids including retinol (ROH), retinal, retinoid acid (RA), retinyl acetate, and RP (Figure 1). Full article
Show Figures

Back to TopTop