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Berlin, Germany

Meinke M.C.,Charite - Medical University of Berlin | Friedrich A.,Charite - Medical University of Berlin | Tscherch K.,University of Hamburg | Haag S.F.,Charite - Medical University of Berlin | And 5 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2013

Nutrition rich in carotenoids is well known to prevent cell damage, premature skin aging, and skin cancer. Cutaneous carotenoids can be enriched in the skin by nutrition and topically applied antioxidants have shown an increase in radical protection after VIS/NIR irradiation. In this paper, it was investigated whether orally administered carotenoids increase the radical scavenging activity and the radical protection of the skin using in vivo electron paramagnetic resonance spectroscopy and the skin lipid profile was investigated applying HPTLC on skin lipid extracts. Furthermore, in vivo Raman resonance spectroscopy was used to measure the cutaneous carotenoid concentration. A double blind placebo controlled clinical study was performed with 24 healthy volunteers, who have shown a slow but significant and effective increase in cutaneous carotenoids in the verum group. The enhancement in carotenoids increases the radical scavenging activity of the skin and provides a significant protection against stress induced radical formation. Furthermore, the skin lipids in the verum group increased compared to the placebo group but only significantly for ceramide [NS]. These results indicate that a supplementation with dietary products containing carotenoids in physiological concentrations can protect the skin against reactive oxygen species and could avoid premature skin aging and other radical associated skin diseases. © 2013 Elsevier B.V. All rights reserved. Source

Meinke M.C.,Charite - Medical University of Berlin | Haag S.F.,Free University of Berlin | Schanzer S.,Charite - Medical University of Berlin | Groth N.,Privatinstitut Galenus GmbH | And 2 more authors.
Photochemistry and Photobiology | Year: 2011

One essential reason for skin ageing is the formation of free radicals by excessive or unprotected sun exposure. Recently, free radical generation in skin has been shown to appear not only after irradiation in the UV wavelength range but also in the infrared (IR) spectral range. Sunscreens are known to protect against radicals generated by UV radiation; however, no data exist for those generated by IR radiation. This paper has investigated four different, commercially available sunscreens and one COLIPA standard with regard to radical formation in the skin after IR irradiation, using electron paramagnetic resonance spectroscopy. The use of sunscreens has led to reduced amounts of radicals compared to untreated skin. Furthermore, absorption and scattering properties and the radical protection factor of the formulations were determined to investigate their influence on the radical protection of the skin. None of these formulations contained an optical absorber in the IR range. The protection efficiency of the sunscreens was shown as being induced by the high scattering properties of the sunscreens, as well as the antioxidants contained in the formulations. © 2010 The American Society of Photobiology. Source

Haag S.F.,Free University of Berlin | Haag S.F.,Charite - Medical University of Berlin | Taskoparan B.,Charite - Medical University of Berlin | Darvin M.E.,Charite - Medical University of Berlin | And 4 more authors.
Experimental Dermatology | Year: 2011

Background: Non-invasive measurements are of major interest for investigating the effects of stress, nutrition, diseases or pharmaceuticals on the antioxidative capacity of the human skin. However, only a few non-invasive methods are available. Material and Methods: The resonance Raman spectroscopy is well established to monitor carotenoids in the skin, but correlations with other antioxidants have not yet been described. Electron paramagnetic resonance spectroscopy used for measurements of free radicals has already been used elsewhere to investigate the reduction of applied long-living nitroxide radicals, caused by skin antioxidants and UV irradiation, but only a single or up to four volunteers were included in these studies. Therefore, in this study, the two methods were applied in parallel on 17 volunteers, and the rate constant of the nitroxide decrease was correlated with the cutaneous carotenoid concentration. Results and Discussion: A correlation with R=0.65 was found, supporting the thesis that different antioxidants protect each other and build an antioxidative network in the skin. The results also give first indications that the carotenoids serve as marker substances for the antioxidative capacity, if the nutrition is well balanced. © 2011 John Wiley & Sons A/S. Source

Meinke M.C.,Charite - Medical University of Berlin | Lauer A.-C.,Charite - Medical University of Berlin | Haag S.F.,Charite - Medical University of Berlin | Darvin M.E.,Charite - Medical University of Berlin | And 2 more authors.
e-SPEN Journal | Year: 2012

Background and aims: The intake of nutritional supplements such as vitamins and antioxidants is popular but still controversially discussed. For effective prevention in premature skin ageing and skin cancer, cutaneous radical scavenging activity should increase after the intake of antioxidants. So far, a non-invasive evaluation procedure for the radical scavenging capacity was not at our disposal. Therefore, electron paramagnetic resonance (EPR) spectroscopy was utilized in vivo to determine the radical scavenging capacity of the skin. Methods: 33 volunteers were investigated, before and after the intake of placebo, vitamin C or a chokeberry peel extract (Aronia) for 28 days. Both experimental products were provided with the same radical scavenging activity. The amount of product corresponded to 125 mg (0.29 mmol) calcium ascorbate per day or 800 mg Aronia combined with 40 mg calcium ascorbate. Results: Oral supplementation with vitamin C and Aronia significantly increase the radical scavenging capacity of the skin by 22% and 23%, respectively using the test radical TEMPO. No uptake was observed within the placebo group. Conclusion: In vivo EPR technique offers a medical evaluation of orally consumed antioxidants regarding the radical scavenging capacity and could demonstrate that a natural product including phenolic compounds has the same effect as vitamin C in the skin if TEMPO is used as a test radical. © 2012 European Society for Clinical Nutrition and Metabolism. Source

Lauer A.-C.,Charite - Medical University of Berlin | Groth N.,Privatinstitut Galenus GmbH | Haag S.F.,Charite - Medical University of Berlin | Darvin M.E.,Charite - Medical University of Berlin | And 2 more authors.
Skin Pharmacology and Physiology | Year: 2013

Vitamin C is a potent radical scavenger and a physiological part of the antioxidant system in human skin. The aim of this study was to measure changes in the radical-scavenging activity of human skin in vivo due to supplementation with different doses of vitamin C and at different time points. Therefore, 33 volunteers were supplemented with vitamin C or placebo for 4 weeks. The skin radical-scavenging activity was measured with electron paramagnetic resonance spectroscopy. After 4 weeks, the intake of 100 mg vitamin C/day resulted in a significant increase in the radical-scavenging activity by 22%. Intake of 180 mg/day even resulted in a significant increase of 37%. No changes were found in the placebo group. A part of the study population was additionally measured after 2 weeks: in this group radical scavenging had already reached maximal activity after 2 weeks. In conclusion, orally administered vitamin C increases the radical-scavenging activity of the skin. The effect occurs fast and is enhanced with higher doses of vitamin C. © 2013 S. Karger AG, Basel. Source

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