Traore-Leroux T, Fumoux F, Chaize J, Roelants G E
Centre de Recherches sur les Trypanosomoses Animales (C.R.T.A.), Burkina Faso, West Africa.
Exp Parasitol. 1987 Dec;64(3):401-9. doi: 10.1016/0014-4894(87)90053-1.
Trypanosoma brucei brucei are lysed when incubated in vitro in a mixture of bovine serum and polyamine. Normal bovine serum alone or polyamine alone does not show any trypanocidal activity. The bovine serum in the mixture can be replaced by purified polyamine oxidase, and addition of polyamine oxidase inhibitors blocks trypanolysis. Using this in vitro lysis test, it is shown that West African cattle which are resistant naturally to trypanosomiasis have a higher trypanolytic activity in their serum than do trypanosensitive cattle (P less than 10(-5]. Seric trypanolytic activity of individual animals remains stable when tested over a period of 18 months; moreover, it is not modified by trypanosome infection. Higher levels of seric polyamine oxidase in resistant cattle were demonstrated also by enzymatic analysis. The factors responsible for trypanolysis have been analyzed. Oxidation of spermidine by polyamine oxidase leads to the production of unstable aldehydes, acrolein, ammonia, O2-, HO, and H2O2. Acrolein and H2O2 show strong trypanolytic activity while the other products do not appear to be toxic for trypanosomes. The physiological importance of polyamine oxidase mediated trypanolysis is unclear; even at peak parasitemia in cattle (10(7) organisms/ml) it can be calculated that trypanosomes would not release enough spermidine for the generation of sufficient quantities of toxic degradation products. Additional polyamines could be released in serum from tissues damaged as a result of the infection.
布氏布氏锥虫在体外与牛血清和多胺混合孵育时会被裂解。单独的正常牛血清或单独的多胺均不显示任何杀锥虫活性。混合物中的牛血清可用纯化的多胺氧化酶替代，添加多胺氧化酶抑制剂可阻断锥虫溶解。通过这种体外裂解试验表明，对锥虫病具有天然抗性的西非牛血清中的锥虫溶解活性高于对锥虫敏感的牛（P小于10^(-5)）。对个体动物进行18个月的血清锥虫溶解活性检测，其活性保持稳定；此外，锥虫感染不会改变其活性。酶分析还表明，抗性牛血清中的多胺氧化酶水平更高。对导致锥虫溶解的因素进行了分析。多胺氧化酶将亚精胺氧化会产生不稳定的醛、丙烯醛、氨、超氧阴离子、羟基自由基和过氧化氢。丙烯醛和过氧化氢显示出很强的杀锥虫活性，而其他产物似乎对锥虫无毒。多胺氧化酶介导的锥虫溶解的生理重要性尚不清楚；即使在牛的寄生虫血症高峰期（每毫升10^7个虫体），据计算锥虫释放的亚精胺也不足以产生足够量的有毒降解产物。感染可能导致组织受损，血清中可能会释放额外的多胺。
