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Photodecomposition and phototoxicity of natural retinoids.

Tolleson WH, Cherng SH, Xia Q, Boudreau M, Yin JJ, Wamer WG, Howard PC, Yu H, Fu PP - Int J Environ Res Public Health (2005)

Bottom Line: 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.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).

View Article: PubMed Central - PubMed

Affiliation: National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA.

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 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).

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Related in: MedlinePlus

Photodecomposition of RP and ROH.
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f3-ijerph-02-00147: Photodecomposition of RP and ROH.

Mentions: It has been shown that RP is much less stable under photoirradiation conditions than is retinol (6). The results shown in Figure 3 confirm that RP (1% in oil-in-water cream) photodecomposed faster than ROH under differing doses of UVA radiation. Boehnlein et al. (9) reported that after RP was topically applied in acetone to human skin, about 18% of RP penetrated the skin in 30 hrs. In addition, approximately 44% of the absorbed RP was hydrolyzed to retinol by skin esterases. As a result, this suggests that the RP and retinol present during a subsequent irradiation would be subject to photodecomposition. Indeed, we have demonstrated that photoirradiation of RP in ethanol under solar simulated light at an irradiance equivalent to terrestrial sunlight resulted in the formation of multiple photodecomposition products (Figure 4). Furthermore, sunlight-induced photodegradation of retinyl esters proceeds much faster than that of retinol, and it has been suggested that cellular retinol binding protein (CRBP) protects retinol from photodegradation (9, 10).


Photodecomposition and phototoxicity of natural retinoids.

Tolleson WH, Cherng SH, Xia Q, Boudreau M, Yin JJ, Wamer WG, Howard PC, Yu H, Fu PP - Int J Environ Res Public Health (2005)

Photodecomposition of RP and ROH.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814709&req=5

f3-ijerph-02-00147: Photodecomposition of RP and ROH.
Mentions: It has been shown that RP is much less stable under photoirradiation conditions than is retinol (6). The results shown in Figure 3 confirm that RP (1% in oil-in-water cream) photodecomposed faster than ROH under differing doses of UVA radiation. Boehnlein et al. (9) reported that after RP was topically applied in acetone to human skin, about 18% of RP penetrated the skin in 30 hrs. In addition, approximately 44% of the absorbed RP was hydrolyzed to retinol by skin esterases. As a result, this suggests that the RP and retinol present during a subsequent irradiation would be subject to photodecomposition. Indeed, we have demonstrated that photoirradiation of RP in ethanol under solar simulated light at an irradiance equivalent to terrestrial sunlight resulted in the formation of multiple photodecomposition products (Figure 4). Furthermore, sunlight-induced photodegradation of retinyl esters proceeds much faster than that of retinol, and it has been suggested that cellular retinol binding protein (CRBP) protects retinol from photodegradation (9, 10).

Bottom Line: 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.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).

View Article: PubMed Central - PubMed

Affiliation: National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA.

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 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).

Show MeSH
Related in: MedlinePlus