Laboratório de Fitotecnologia, Departamento de Farmácia, Universidade Federal de Ouro Preto, Campus Morro Do Cruzeiro, Ouro Preto, Minas Gerais, CEP 35400-000, Brazil.
Laboratório de Substâncias Antitumorais, Departamento de Farmacologia, Universidade Federal de Minas Gerais, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil.
Free Radic Biol Med. 2020 Nov 1;159:54-65. doi: 10.1016/j.freeradbiomed.2020.07.022. Epub 2020 Jul 31.
Recently, there has been a demand for the replacement of chemical sunscreens with natural compounds that could prevent or restore UV-induced skin damage. Here, we investigated the photoprotective influence of the Melaleuca leucadendron ethanolic flower extract (EEMec) on factors involved in cellular and molecular UVB-induced oxidative stress in human skin keratinocytes (HaCaT). The phytochemical constituents, antioxidant potential by DPPH assay, content of total phenolic and flavonoid compounds in EEMec were evaluated. HaCaT cells were treated with EEMec followed by irradiation with UVB. CAT activity; GSH and ROS levels; and SOD1, GPx, CAT and COX-2 expression assays were employed to verify the oxidative stress, as well as EEMec effect on transmembrane transport, and pro-inflammatory and pro-apoptotic protein expression. EEMec reverted the viability loss of HaCaT cells after irradiation with UVB, exhibited significant antioxidant capacity and free radical scavenging activity in vitro, inhibited COX-2 expression and ensure protection of DNA-damage. EEMec shown a great photoprotective property to prevent keratinocytes damage induced by UV radiation and, thus a candidate potential to application as an adjuvant in sunscreen formulations as a strategy to reduce risk of sunburn and prevent skin diseases associated with UV-induced inflammation and cancer.
最近，人们要求用可以预防或修复紫外线引起的皮肤损伤的天然化合物替代化学防晒霜。在这里，我们研究了桃金娘醇花提取物（EEMec）对人皮肤角质形成细胞（HaCaT）中细胞和分子 UVB 诱导氧化应激相关因素的光保护作用。评估了 EEMec 的植物化学成分、DPPH 测定法的抗氧化潜力、总酚和类黄酮化合物的含量。用 EEMec 处理 HaCaT 细胞，然后用 UVB 照射。采用 CAT 活性；GSH 和 ROS 水平；以及 SOD1、GPx、CAT 和 COX-2 表达测定法来验证氧化应激，以及 EEMec 对跨膜转运以及促炎和促凋亡蛋白表达的影响。EEMec 逆转了 HaCaT 细胞经 UVB 照射后的活力损失，在体外表现出显著的抗氧化能力和自由基清除活性，抑制了 COX-2 的表达，并确保了对 DNA 损伤的保护。EEMec 具有很好的光保护性能，可防止紫外线辐射引起的角质形成细胞损伤，因此有望作为防晒配方中的辅助剂，以降低晒伤风险并预防与紫外线引起的炎症和癌症相关的皮肤疾病。
