کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6382480 | 1625962 | 2013 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Oxidative damage and apoptosis induced by microcystin-LR in the liver of Rana nigromaculata in vivo
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
علوم آبزیان
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
Microcystins (MCs) are hepatotoxins with potent inhibitor activity of protein phosphatases PP1 and PP2A. The present study shows that MC-LR can induce severe oxidative damage and apoptosis in the livers of frogs (Rana nigromaculata) exposed to 1 μg/L MC-LR for 7 and 14 d in vivo. Ultrastructural observation showed the apoptotic morphology of perinuclear chromatin margination and swollen mitochondria, indicating that MC-LR can significantly damage frog liver. Reactive oxygen species (ROS) production and malondialdehyde (MDA) content were positively correlated with exposure time. Meanwhile, reduced glutathione (GSH) content and GSH peroxidase (GPx) activity rapidly decreased after prolonged exposure to 1 μg/L MC-LR in a time-dependent manner. These results imply that the antioxidant defense systems of the liver were damaged. Enhanced apoptosis of cells in the livers of MC-treated frogs was detected by terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling (TUNEL) associated with up-regulation of the mitochondrial system. MC-LR significantly stimulated the livers to release cytochrome c, which improved the protein expressions of Bax, caspase-3, and caspase-9 (p < 0.01) and inhibited the protein expression of Bcl-2 with prolonged exposure (p < 0.01) via the mitochondrial pathway. These results imply that the mitochondrial pathway has a key function in toxin-induced liver cell apoptosis. The expression of caspase-8 was induced significantly (p < 0.01), which illustrates the mechanism that the death receptor pathway is also involved in apoptosis. The present findings show that MC-LR can induce apoptosis in frog liver, which may be related with the decline of amphibian populations. The World Health Organization-recommended drinking water limit for MC-LR in water may be not safe for amphibians.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Aquatic Toxicology - Volumes 140â141, 15 September 2013, Pages 11-18
Journal: Aquatic Toxicology - Volumes 140â141, 15 September 2013, Pages 11-18
نویسندگان
Hangjun Zhang, Chenchen Cai, Wendi Fang, Jia Wang, Yue Zhang, Jiayu Liu, Xiuying Jia,