Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
Vet Parasitol. 2011 Aug 25;180(3-4):209-14. doi: 10.1016/j.vetpar.2011.03.011. Epub 2011 Mar 17.
In order to investigate the alterations of erythrocyte protective antioxidant mechanisms, lipid peroxidation and trace elements associated with anemia in bovine tropical theileriosis, an infected group comprised of 50 crossbred Holstein cattle, about 1-2 years old, naturally infected with Theileria annulata, were divided into 4 subgroups according to their parasitemia rates (<1%, 1-3%, 3-5%, >5%) and also 10 healthy cattle as control were selected. Blood samples were taken and hematological parameters, the activities of antioxidant enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase and serum concentrations of some antioxidant trace elements (copper, iron, zinc, manganese and selenium) were measured. As an index of lipid peroxidation, the level of Malondialdehyde (MDA) was also determined. The results showed a conspicuous decrease in the activities of SOD, GPX and catalase (P<0.01), and a significant decrease in the serum concentrations of Cu, Zn, Mn and Se in cattle with higher than 1% parasitemia (P<0.05) compared to the control. In addition, remarkable elevations in the MDA level (P<0.01) and serum concentration of iron (P<0.05) were observed in the infected animals. These findings pointed to the occurrence of exacerbating oxidative injuries to erythrocytes during parasitemia. Furthermore, it can be concluded that infection with T. annulata can interfere with protective antioxidant mechanisms of RBCs against oxidative damages, which promote the development of anemia.
为了研究红细胞保护抗氧化机制的改变、脂类过氧化作用以及与贫血相关的微量元素在牛热带泰勒虫病中的变化，将 50 头大约 1-2 岁的杂交荷斯坦奶牛分为 4 个亚组，根据它们的寄生虫血症率（<1%、1-3%、3-5%、>5%），并且选择 10 头健康的牛作为对照。采集血液样本并测量血液学参数、抗氧化酶（超氧化物歧化酶[SOD]、谷胱甘肽过氧化物酶[GPX]和过氧化氢酶）的活性以及一些抗氧化微量元素（铜、铁、锌、锰和硒）的血清浓度。作为脂质过氧化作用的指标，还测定了丙二醛（MDA）的水平。结果表明，在寄生虫血症高于 1%的牛中，SOD、GPX 和过氧化氢酶的活性显著降低（P<0.01），并且 Cu、Zn、Mn 和 Se 的血清浓度显著降低（P<0.05），与对照组相比。此外，感染动物的 MDA 水平（P<0.01）和铁血清浓度（P<0.05）显著升高。这些发现表明在寄生虫血症期间红细胞发生了加剧的氧化损伤。此外，可以得出结论，感染 T. annulata 会干扰 RBC 对氧化损伤的保护抗氧化机制，从而促进贫血的发展。
