Bernd A, Simon S, Ramirez Bosca A, Kippenberger S, Diaz Alperi J, Miquel J, Villalba Garcia J F, Pamies Mira D, Kaufmann R
Department of Dermatology, Clinical Hospital of the J. W. Goethe University, Frankfurt, Germany.
Photochem Photobiol. 1999 Feb;69(2):218-21. doi: 10.1562/0031-8655(1999)069<0218:peoeic>2.3.co;2.
Extracts of Hypericum perforatum (St. John's wort) are used in the treatment of depression. They contain the plant pigment hypericin and hypericin derivates. These compounds have light-dependent activities. In order to estimate the potential risk of phototoxic skin damage during antidepressive therapy, we investigated the phototoxic activity of hypericin extract using cultures of human keratinocytes and compared it with the effect of the well-known phototoxic agent psoralen. The absorbance spectrum of our Hypericum extract revealed maxima in the whole UV range and in parts of the visible range. We cultivated human keratinocytes in the presence of different Hypericum concentrations and irradiated the cells with 150 mJ/cm2 UVB, 1 J/cm2 UVA or 3 h with a white light of photon flux density 2.6 mumol m-2 s-1. The determination of the bromodeoxyuridine incorporation rate showed a concentration- and light-dependent decrease in DNA synthesis with high hypericin concentrations (> or = 50 micrograms/mL) combined with UVA or visible light radiation. In the case of UVB irradiation a clear phototoxic cell reaction was not detected. We found phototoxic effects even with 10 ng/mL psoralen using UVA with the same study design as in the case of the Hypericum extract. These results confirm the phototoxic activity of Hypericum extract on human keratinocytes. However, the blood levels that are to be expected during antidepressive therapy are presumably too low to induce phototoxic skin reactions.
贯叶连翘提取物用于治疗抑郁症。它们含有植物色素金丝桃素及其衍生物。这些化合物具有光依赖性活性。为了评估抗抑郁治疗期间光毒性皮肤损伤的潜在风险，我们使用人角质形成细胞培养物研究了金丝桃素提取物的光毒性活性，并将其与著名的光毒性剂补骨脂素的作用进行了比较。我们的贯叶连翘提取物的吸收光谱在整个紫外范围内以及部分可见光范围内显示出最大值。我们在不同浓度的贯叶连翘存在下培养人角质形成细胞，并用150 mJ/cm² 的UVB、1 J/cm² 的UVA或光子通量密度为2.6 μmol m⁻² s⁻¹ 的白光照射细胞3小时。溴脱氧尿苷掺入率的测定表明，在高浓度金丝桃素（≥50微克/毫升）与UVA或可见光辐射结合的情况下，DNA合成呈浓度和光依赖性下降。在UVB照射的情况下，未检测到明显的光毒性细胞反应。在与贯叶连翘提取物相同的研究设计中，使用UVA时，即使补骨脂素浓度为10纳克/毫升，我们也发现了光毒性作用。这些结果证实了贯叶连翘提取物对人角质形成细胞的光毒性活性。然而，抗抑郁治疗期间预期的血药浓度可能过低，不足以引起光毒性皮肤反应。
