Höhn Annika, Hartmann Petra, Gebhart Veronika, Sonntag Johanna, Grune Tilman, Jung Tobias
Department for "Molecular Toxicology", German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Nuthetal, Germany.
Department of Nutritional Toxicology, Friedrich-Schiller-University Jena, Jena, Germany.
Photochem Photobiol. 2015 Jul-Aug;91(4):887-94. doi: 10.1111/php.12439. Epub 2015 Mar 12.
In this study, the athermal effects of water-filtered infrared A (wIRA)-irradiation (780-1400 nm) on human dermal fibroblasts were investigated. For this purpose, cells were exposed to wIRA-irradiation (178 mW cm(-2) for 1 h), while a sophisticated experimental setup prevented warming of the samples exceeding 0.1°C. The investigated parameters were the formation of reactive oxygen species (ROS), mitochondrial membrane potential and superoxide release, protein oxidation, proliferation rate, as well as intracellular Ca(2+) -release in single cells, most of them quantified via fluorescence microscopy and fluorimetric techniques. The existence of actual athermal wIRA-effects is still intensively discussed, since their detection requires a careful experimental setup and both efficient and powerful temperature regulation of the exposed samples. Here, we can definitively show that some of the supposed athermal wIRA-effects may be rather artifacts, since wIRA did not reveal any impact on the above mentioned parameters-as long as the temperature of the exposed cells was carefully maintained. Though, we were able to identify an athermal DNA-protective wIRA-effect, since the induced DNA damage (quantified via 8-Oxo-G-formation) was significantly decreased after a subsequent UVB-exposure. These results suggest that many of the supposed athermal wIRA-effects can be induced by pure warming of the samples, independent from any wIRA-irradiation.
在本研究中，我们研究了水过滤红外A（wIRA）辐射（780 - 1400纳米）对人皮肤成纤维细胞的非热效应。为此，将细胞暴露于wIRA辐射（178毫瓦/平方厘米，持续1小时），同时一个精密的实验装置可防止样品升温超过0.1°C。所研究的参数包括活性氧（ROS）的形成、线粒体膜电位和超氧化物释放、蛋白质氧化、增殖率以及单细胞内的细胞内Ca(2+)释放，其中大部分通过荧光显微镜和荧光技术进行定量。实际的非热wIRA效应的存在仍在激烈讨论中，因为其检测需要精心的实验设置以及对暴露样品进行高效且强大的温度调节。在此，我们可以明确表明，一些所谓的非热wIRA效应可能相当于是假象，因为只要仔细维持暴露细胞温度，wIRA对上述参数并未显示出任何影响。不过，我们能够确定一种非热的DNA保护wIRA效应，因为在随后的UVB暴露后，诱导的DNA损伤（通过8 - Oxo - G形成进行定量）显著降低。这些结果表明，许多所谓的非热wIRA效应可能是由样品单纯升温诱导产生的，与任何wIRA辐射无关。
