Abstract | BACKGROUND:
Skin cancer is a major public health concern, and the majority of cases are caused by solar ultraviolet radiation (UVR) exposure, which suppresses skin immunity. Omega-3 (n-3) PUFAs protect against photoimmunosuppression and skin cancer in mice, but the impact in humans is unknown. OBJECTIVES: We hypothesized that EPA-rich n-3 PUFA would abrogate photoimmunosuppression in humans. Therefore, a nutritional study was performed to assess the effect on UVR suppression of cutaneous cell-mediated immunity (CMI) reflected by nickel contact hypersensitivity (CHS). DESIGN: In a double-blind, randomized controlled study, 79 volunteers ( nickel-allergic women, 22-60 y old, with phototype I or II) took 5 g n-3 PUFA-containing lipid (70% EPA plus 10% DHA) or a control lipid daily for 3 mo. After supplementation, nickel was applied to 3 skin sites preexposed on 3 consecutive days to 1.9, 3.8, or 7.6 J/cm(2) of solar-simulated radiation (SSR) and to 3 unexposed control sites. Nickel CHS responses were quantified after 72 h and the percentage of immunosuppression by SSR was calculated. Erythrocyte [red blood cell (RBC)] EPA was measured by using gas chromatography. RESULTS: SSR dose-related suppression of the nickel CHS response was observed in both groups. Photoimmunosuppression appeared less in the n-3 PUFA group than in the control group (not statistically significant [mean difference (95% CI): 6.9% (-2.1%, 15.9%)]). The difference was greatest at 3.8 J/cm(2) SSR [mean difference: 11% (95% CI: 0.5%, 21.4%)]. Postsupplementation RBC EPA was 4-fold higher in the n-3 PUFA group than in the control group (mean difference: 2.69% (95% CI: 2.23%, 3.14%), which confirmed the EPA bioavailability. CONCLUSION: Oral n-3 PUFAs appear to abrogate photoimmunosuppression in human skin, providing additional support for their chemopreventive role; verification of study findings is required. This trial was registered at clinicaltrials.gov as NCT01032343.
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Authors | Suzanne M Pilkington, Karen A Massey, Susan P Bennett, Naser Mi Al-Aasswad, Khaled Roshdy, Neil K Gibbs, Peter S Friedmann, Anna Nicolaou, Lesley E Rhodes |
Journal | The American journal of clinical nutrition
(Am J Clin Nutr)
Vol. 97
Issue 3
Pg. 646-52
(Mar 2013)
ISSN: 1938-3207 [Electronic] United States |
PMID | 23364005
(Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
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Chemical References |
- Fatty Acids, Omega-3
- Nickel
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Topics |
- Adult
- Dermatitis, Contact
(immunology, prevention & control)
- Dietary Supplements
- Double-Blind Method
- Erythrocytes
(drug effects, immunology)
- Fatty Acids, Omega-3
(administration & dosage, blood)
- Female
- Humans
- Immune Tolerance
(immunology, radiation effects)
- Immunity, Cellular
(drug effects)
- Middle Aged
- Nickel
(adverse effects, metabolism)
- Skin
(drug effects, immunology, radiation effects)
- Solar Energy
- Ultraviolet Rays
(adverse effects)
- Young Adult
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