title: Regulation of nodularin-induced apoptosis by epigallocatechin-3-gallate on fish lymphocytes in vitro.
abstract: Nodularin is one of the most conspicuous and widespread pollutants that elicit water ecological hazards to fish, causing serious damage on the immune system and physiological functions. Nodularin can cause oxidative stress-induced apoptosis on fish lymphocytes. The regulatory effects of epigallocatechin-3-gallate (EGCG) at 10, 100, and 1000 μg/L levels on the antioxidant defense system and apoptosis of Carassius auratus lymphocytes exposed to a high dose of nodularin (100 μg/L) were quantified in vitro. EGCG reduced nodularin-induced oxidative damage on fish immune cells. This compound significantly increased the activities of superoxide dismutase and catalase and the level of glutathione but decreased the levels of intracellular reactive oxygen species and malondialdehyde. Flow cytometry results showed that the percentages of apoptotic cells after treatment with 10, 100, and 1000 μg/L EGCG for 12 h reached 27.9%, 19.1%, and 13.7%, respectively. By contrast, the nodularin alone-induced group showed a high percentage of apoptosis (44.2%). Western blot analysis showed the increased expression of bcl-2 and the decreased expression of bax and caspase-3 in EGCG-treated fish lymphocytes. EGCG also inhibited the potential collapse of the mitochondrial membrane. Overall, EGCG can inhibit nodularin-induced apoptosis and protect the normal immunity of fish by regulating bax/bcl-2 and blocking the downstream of mitochondrial apoptosis pathway with increased intracellular antioxidant enzyme activity.
authors: Department of Environmental Sciences, Hangzhou Normal University, Xuelin Road 16#, Xiasha Gaojiao Dongqu, Hangzhou, Zhejiang Province 310036, China. zhanghangjun@gmail.com
authors: Hangjun
authors: H
authors: Zhang
authors: Dandan
authors: D
authors: Shao
authors: Yingzhu
authors: Y
authors: Wu
authors: Bingru
authors: B
authors: Dai
authors: Chenchen
authors: C
authors: Cai
authors: Wendi
authors: W
authors: Fang
authors: Binhui
authors: B
authors: Ye
authors: Yue
authors: Y
authors: Zhang
authors: Jiayu
authors: J
authors: liu
authors: Xiuying
authors: X
authors: Jia
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western / Q000662:veterinary; D002392:Catechin / Q000031:analogs & derivatives* / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D006054:Goldfish / Q000378:metabolism*; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008387:Marine Toxins / Q000633:toxicity; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D046932:Nodularia / Q000737:chemistry; D018384:Oxidative Stress / Q000187:drug effects; D010456:Peptides, Cyclic / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D008387:Marine Toxins; D010456:Peptides, Cyclic; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; C063998:nodularin; D002392:Catechin; C045651:epigallocatechin gallate