University of Tirana, Faculty of Natural Sciences, Department of Biology, Tirana, Albania.
University of Tirana, Faculty of Natural Sciences, Department of Biology, Tirana, Albania.
Fish Shellfish Immunol. 2018 May;76:101-109. doi: 10.1016/j.fsi.2018.02.042. Epub 2018 Feb 24.
The manganese contamination has become a global problem, recently, because it is perceived as a real threat to the human health and the environment. It is well-known that overexposure to Mn may have negative physiological effects on fish and other organisms inhabiting heavy metal polluted waters. To the best of our knowledge, studies relating with manganese effects on fish antioxidant enzyme response in the blood, immunocompetence and erythron profile alteration, are scarce. In this study, the acute sub-lethal effects of manganese on blood antioxidant response, immune status and erythron profile were determined by exposing the freshwater model organism, Carassius auratus, to two doses of this metal (3.88 ± 0.193 mg/L and 7.52 ± 0.234 mg/L Mn) for 96 h. Significant increases in blood antioxidant enzyme activity like superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST), were observed in fish exposed to manganese. Furthermore, plasmatic glucose and cortisol levels increased, while total protein decreased significantly. White blood cell differential count revealed a significant increase in monocyte and neutrophil number and a significant decrease of lymphocyte's number in fish exposed to manganese compared with those of control group. That can be considered as a clear evidence of altered immune system. Measured of erythron profile revealed a significant increasing of cellular and nuclear alteration of red blood cells, with karryorhectic, dividing and micronucleated erythrocytes in exposed fish, indicating the cytotoxic and genotoxic effects Mn ions. Our data shown also that manganese could trigger antioxidant response, modulate immune response and induce erythron profile modification leading to eryptosis, compromising the blood oxygen carrying capacity, and overall health status in fish. This may suggest those parameters consider as useful biomarkers for monitoring effects of sub-lethal metal exposure on fish.
锰污染已成为一个全球性问题，因为它被认为是对人类健康和环境的真正威胁。众所周知，鱼类和其他生活在重金属污染水域中的生物过度暴露于锰可能会产生负面的生理影响。据我们所知，关于锰对鱼类血液抗氧化酶反应、免疫能力和红细胞谱改变的影响的研究很少。在这项研究中，通过将淡水模式生物鲫鱼暴露于两种剂量的锰（3.88±0.193mg/L 和 7.52±0.234mg/L Mn）96 小时，确定了锰对血液抗氧化反应、免疫状态和红细胞谱的急性亚致死影响。暴露于锰的鱼血液中抗氧化酶活性（如超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽-S-转移酶（GST））显著增加。此外，血浆葡萄糖和皮质醇水平显著升高，而总蛋白显著降低。白细胞分类计数显示，暴露于锰的鱼单核细胞和中性粒细胞数量显著增加，淋巴细胞数量显著减少，表明免疫系统发生改变。红细胞谱的测量显示，暴露于锰的鱼的红细胞发生了明显的细胞和核改变，出现了核碎裂、分裂和微核红细胞，表明 Mn 离子具有细胞毒性和遗传毒性作用。我们的数据还表明，锰可以触发抗氧化反应、调节免疫反应并诱导红细胞谱改变，导致红细胞发生皱缩，从而降低鱼类的血液携氧能力和整体健康状况。这可能表明这些参数可以作为监测亚致死金属暴露对鱼类影响的有用生物标志物。
