title: Dietary selenium protect against redox-mediated immune suppression induced by methylmercury exposure.
abstract: The antagonism between selenium (Se) and mercury (Hg) has been widely recognized, however, the protective role of Se against methylmercury (MeHg) induced immunotoxicity and the underlying mechanism is still unclear. In the current study, MeHg exposure (0.01 mM via drinking water) significantly inhibited the lymphoproliferation and NK cells functions of the female Balb/c mice, while dietary Se supplementation (as Se-rich yeast) partly or fully recovered the observed immunotoxicity, indicating the protective role of Se against MeHg-induced immune suppression in mice. Besides, MeHg exposure promoted the generation of the reactive oxygen species (ROS), reduced the levels of nonenzymic and enzymic antioxidants in target organs, while dietary Se administration significantly diminished the MeHg-induced oxidative stress and subsequent cellular dysfunctions (lipid peroxidation and protein oxidation). Two possible mechanisms of Se's protective effects were further revealed. Firstly, the reduction of mercury concentrations (less than 25%, modulated by Se supplementation) in the target organs might contribute, but not fully explain the alleviated immune suppression. Secondly and more importantly, Se could help to maintain/or elevate the activities of several key antioxidants, therefore protect the immune cells against MeHg-induced oxidative damage.
authors: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
authors: Xuan
authors: X
authors: Li
authors: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
authors: Daqiang
authors: D
authors: Yin
authors: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
authors: Jiaoyang
authors: J
authors: Yin
authors: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
authors: Qiqing
authors: Q
authors: Chen
authors: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: wangr@tongji.edu.cn.
authors: Rui
authors: R
authors: Wang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D019587:Dietary Supplements; D060766:Drinking Water / Q000032:analysis; D005260:Female; D007107:Immune System / Q000187:drug effects* / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008767:Methylmercury Compounds / Q000633:toxicity*; D051379:Mice; D008807:Mice, Inbred BALB C; D010084:Oxidation-Reduction / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects; D020011:Protective Agents / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012643:Selenium / Q000494:pharmacology*; D013154:Spleen / Q000187:drug effects / Q000378:metabolism; D013950:Thymus Gland / Q000187:drug effects / Q000378:metabolism
chemical_list: D000975:Antioxidants; D060766:Drinking Water; D008767:Methylmercury Compounds; D020011:Protective Agents; D017382:Reactive Oxygen Species; D012643:Selenium; C004925:methylmercuric chloride
keywords: Antagonism; Immunotoxic effects; Methylmercury; Oxidative stress; Selenium