Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Palackeho tr. 1-3, 61242 Brno, Czech Republic.
Toxicon. 2013 Oct;73:1-8. doi: 10.1016/j.toxicon.2013.06.016. Epub 2013 Jul 4.
Toxic cyanobacteria represent a serious health and ecological problem in drinking and recreational waters worldwide. Some previous toxicological studies investigated effects of isolated microcystins on laboratory rodents including mice and rats. However, much less attention has been paid to more realistic exposure situations such as the effects of MCs accumulated in food. The objectives of the present study were to provide a simple model simulation of the food chain in order to evaluate impacts of microcystins (MCs) on rat immune and haematologicalparameters. Impacts of feeding experimental rats with a diet containing fish meat with and without microcystins and complex toxic biomass have been studied during a 28 day exposure. Red blood cell parameters (RBC counts, haematocrit values, MCH, MCV and MCHC) showed significant differences in experimental groups (p ≤ 0.05, p ≤ 0.01) in comparison with the control group. We also detected an immunomodulatory effect in the experimental groups. NK cells and γδ+ T lymphocytes were significantly increased in peripheral blood in the group exposed to isolated microcystin in the food. Significant change in the ratio of CD4+ and CD8+ cells (increase of CD4+ and a drop in CD8+) was found in the group with added cyanobacterial biomass with low concentration of MCs. The greatest changes in lymphoid organs were observed in the same groups. There was an increase of spleen subpopulations of γδ+ T lymphocytes as well as of IgM+ lymphocytes (B lymphocytes) and CD8+ T lymphocytes. Indeed, the modulation of CD4+ and CD8+ of peripheral lymphocytes was associated with similar changes in thymic lymphocytic subpopulations. In summary, food containing fish meat with considerable doses of microcystins (or toxic cyanobacterial biomass) induces significant changes in RBC parameters and influence preferably innate part of the immune system represented by NK cells and by gamma-delta T cells, which are known to play role as a bridge between adaptive and innate immune response.
有毒蓝藻是全球饮用水和娱乐水中一个严重的健康和生态问题。一些之前的毒理学研究调查了分离的微囊藻毒素对实验啮齿动物（包括小鼠和大鼠）的影响。然而，对于更现实的暴露情况，如积累在食物中的微囊藻毒素的影响，关注较少。本研究的目的是提供一个简单的食物链模型模拟，以评估微囊藻毒素（MCs）对大鼠免疫和血液学参数的影响。在 28 天的暴露期间，研究了用含有微囊藻毒素和复杂毒性生物量的鱼肉喂养实验大鼠以及不含微囊藻毒素的鱼肉对大鼠的影响。与对照组相比，实验组的红细胞参数（RBC 计数、血细胞比容值、MCH、MCV 和 MCHC）有显著差异（p≤0.05，p≤0.01）。我们还检测到实验组的免疫调节作用。在食物中暴露于分离的微囊藻毒素的实验组中，外周血中的 NK 细胞和γδ+T 淋巴细胞显著增加。在添加低浓度微囊藻毒素的蓝藻生物量的实验组中，CD4+和 CD8+细胞的比例发生了显著变化（CD4+增加，CD8+减少）。在同一组中观察到淋巴器官的最大变化。γδ+T 淋巴细胞以及 IgM+淋巴细胞（B 淋巴细胞）和 CD8+T 淋巴细胞的脾脏亚群增加。事实上，外周淋巴细胞 CD4+和 CD8+的调节与胸腺淋巴细胞亚群的类似变化有关。总之，含有大量微囊藻毒素（或有毒蓝藻生物量）的鱼肉会引起 RBC 参数的显著变化，并优先影响 NK 细胞和γδ+T 细胞等先天免疫系统，这些细胞被认为是适应性和先天免疫反应之间的桥梁。
