Phototoxic lysis of erythrocytes from humans is reduced after oral intake of ascorbic acid and d-α-tocopherol
| Autor: | Bernhard Przybilla, Bernadette Eberlein-König, Marianne Placzek |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Adult
Male Erythrocytes Ultraviolet Rays medicine.medical_treatment Immunology Administration Oral Radiation-Protective Agents Ascorbic Acid Dermatology In Vitro Techniques Pharmacology Hemolysis Antioxidants Double-Blind Method Fenofibrate In vivo medicine Humans Vitamin E Immunology and Allergy Radiology Nuclear Medicine and imaging Photosensitizer Tocopherol Photolysis Photosensitizing Agents Vitamin C Chemistry General Medicine Middle Aged medicine.disease Ascorbic acid Biochemistry Female Phototoxicity |
| Zdroj: | Photodermatology, Photoimmunology & Photomedicine. 13:173-177 |
| ISSN: | 0905-4383 |
| DOI: | 10.1111/j.1600-0781.1997.tb00224.x |
| Popis: | Ultraviolet (UV) radiation causes hemolysis of human erythrocytes in the presence of photosensitizers. This can be used as an in vitro model for evaluating photosensitizing properties of substances. Antioxidants such as ascorbic acid (vitamin C) and d-alpha-tocopherol (vitamin E) have been found to be photoprotective in such test systems. We assessed the effect of combined systemic intake of both ascorbic acid and d-alpha-tocopherol by human volunteers on phototoxic in vitro lysis of their erythrocytes. In a double-blind placebo-controlled study, 10 subjects took daily 2 g ascorbic acid combined with 1000 IU d-alpha-tocopherol, and 10 took a placebo. Blood was taken before and after 7 days of treatment, erythrocytes were prepared and then incubated with 10(-3) mol/l fenofibrate, a photosensitizer acting in the UVA and UVB region. The suspensions were exposed to radiation rich in UVA (up to 40 J/cm2 UVA) or to radiation rich in UVB (up to 1.6 J/cm2). Photohemolysis of the samples was calculated as a percentage of complete hemolysis. At the end of the treatment phase, in the placebo group photohemolysis was not significantly reduced compared with the initial values at all irradiation doses except for 1.6 J/cm2 UVB (96% vs 79%; P < 0.01). In the group taking vitamins, photohemolysis was significantly reduced at nearly all UV doses, most impressively after moderate UVA irradiation (20 J/cm2 UVA: 86.5% vs 14.5%; P < 0.01). It is concluded that the results of the photohemolysis test are influenced by the antioxidative status of the cell donor and that ascorbic acid and d-alpha-tocopherol also may protect against phototoxic damage in vivo. |
| Databáze: | OpenAIRE |
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