Curnow Alison, Owen Sara J
Clinical Photobiology, European Centre for Environment and Human Health, University of Exeter Medical School, Knowledge Spa, Royal Cornwall Hospital, Truro, Cornwall TR1 3HD, UK.
Oxid Med Cell Longev. 2016;2016:7053897. doi: 10.1155/2016/7053897. Epub 2016 Feb 3.
As lifetime exposure to ultraviolet (UV) radiation has risen, the deleterious effects have also become more apparent. Numerous sunscreen and skincare products have therefore been developed to help reduce the occurrence of sunburn, photoageing, and skin carcinogenesis. This has stimulated research into identifying new natural sources of effective skin protecting compounds. Alkaline single-cell gel electrophoresis (comet assay) was employed to assess aqueous extracts derived from soil or hydroponically glasshouse-grown roots of Althea officinalis (Marshmallow) and Astragalus membranaceus, compared with commercial, field-grown roots. Hydroponically grown root extracts from both plant species were found to significantly reduce UVA-induced DNA damage in cultured human lung and skin fibroblasts, although initial Astragalus experimentation detected some genotoxic effects, indicating that Althea root extracts may be better suited as potential constituents of dermatological formulations. Glasshouse-grown soil and hydroponic Althea root extracts afforded lung fibroblasts with statistically significant protection against UVA irradiation for a greater period of time than the commercial field-grown roots. No significant reduction in DNA damage was observed when total ultraviolet irradiation (including UVB) was employed (data not shown), indicating that the extracted phytochemicals predominantly protected against indirect UVA-induced oxidative stress. Althea phytochemical root extracts may therefore be useful components in dermatological formulations.
随着紫外线（UV）辐射的终生暴露量增加，其有害影响也变得更加明显。因此，人们开发了许多防晒和护肤产品，以帮助减少晒伤、光老化和皮肤癌发生的几率。这激发了对寻找有效皮肤保护化合物新天然来源的研究。采用碱性单细胞凝胶电泳（彗星试验）来评估药用蜀葵（锦葵）和黄芪的土壤水提取物或温室水培根提取物，并与商业化种植的田间根进行比较。结果发现，两种植物的水培根提取物均能显著减少培养的人肺和皮肤成纤维细胞中UVA诱导的DNA损伤，不过黄芪的初步实验检测到了一些遗传毒性效应，这表明蜀葵根提取物可能更适合作为皮肤科制剂的潜在成分。温室种植的土壤和水培蜀葵根提取物为肺成纤维细胞提供的抗UVA辐射的保护作用在统计学上比商业化种植的田间根更显著，且持续时间更长。当采用总紫外线辐射（包括UVB）时，未观察到DNA损伤有显著减少（数据未显示），这表明提取的植物化学物质主要是针对间接UVA诱导的氧化应激起保护作用。因此，蜀葵植物化学根提取物可能是皮肤科制剂中的有用成分。
