{"title":"Bystander effect of ultraviolet A radiation protects A375 melanoma cells by induction of antioxidant defense.","authors":"Surajit Hansda, Rita Ghosh","doi":"10.1080/26896583.2021.1994820","DOIUrl":null,"url":null,"abstract":"<p><p>Ultraviolet (UV) irradiated cells release factors that result in varied responses by non-irradiated cells via bystander effects (BE). The UV-BE is dependent on the cell types involved and on the wavelength of the radiation. Using conditioned medium from UVA-irradiated A375 human melanoma cells (UVA-CM), UVA-bystander response was evaluated on the viability of naïve A375 cells. UVA-CM treatment itself did not alter cell viability; however, UVA-CM treated bystander cells were more resistant to the lethal action of UVA, UVB, UVC or H<sub>2</sub>O<sub>2</sub>. Effects of UVA-CM on cell proliferation, mechanism of cell death, DNA damage, malondialdehyde formation, generation of reactive oxygen species (ROS) and antioxidant status were studied in A375 cells. We observed that UVA-CM triggered antioxidant defenses to elicit protective responses through elevation of antioxidant enzyme activities in cells, which persisted until 5 h after exposure to UVA-CM. This was possibly responsible for decreased generation of ROS and diminished DNA and membrane damage in cells. These bystander cells were resistant to killing when exposed to different genotoxic agents. Damaged nuclei, induction of apoptosis and autophagic death were also lowered in these cells. The influence of UVA-CM on cancer stem cells side population was assessed.Highlights:UVA radiation induced bystander effects in A375 cellsDamage by genotoxicants is suppressed due to lower ROS generation on UVA-CM treatmentUVA-CM exposure enhanced higher activities of CAT and GPxResistance to genotoxic agents in such cells was due to elevated antioxidant defenceUVA-bystander phenomenon was a protective response.</p>","PeriodicalId":53200,"journal":{"name":"Journal of Environmental Science and Health Part C-Toxicology and Carcinogenesis","volume":"40 1","pages":"46-67"},"PeriodicalIF":1.2000,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Environmental Science and Health Part C-Toxicology and Carcinogenesis","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1080/26896583.2021.1994820","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2021/12/13 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 3
Abstract
Ultraviolet (UV) irradiated cells release factors that result in varied responses by non-irradiated cells via bystander effects (BE). The UV-BE is dependent on the cell types involved and on the wavelength of the radiation. Using conditioned medium from UVA-irradiated A375 human melanoma cells (UVA-CM), UVA-bystander response was evaluated on the viability of naïve A375 cells. UVA-CM treatment itself did not alter cell viability; however, UVA-CM treated bystander cells were more resistant to the lethal action of UVA, UVB, UVC or H2O2. Effects of UVA-CM on cell proliferation, mechanism of cell death, DNA damage, malondialdehyde formation, generation of reactive oxygen species (ROS) and antioxidant status were studied in A375 cells. We observed that UVA-CM triggered antioxidant defenses to elicit protective responses through elevation of antioxidant enzyme activities in cells, which persisted until 5 h after exposure to UVA-CM. This was possibly responsible for decreased generation of ROS and diminished DNA and membrane damage in cells. These bystander cells were resistant to killing when exposed to different genotoxic agents. Damaged nuclei, induction of apoptosis and autophagic death were also lowered in these cells. The influence of UVA-CM on cancer stem cells side population was assessed.Highlights:UVA radiation induced bystander effects in A375 cellsDamage by genotoxicants is suppressed due to lower ROS generation on UVA-CM treatmentUVA-CM exposure enhanced higher activities of CAT and GPxResistance to genotoxic agents in such cells was due to elevated antioxidant defenceUVA-bystander phenomenon was a protective response.