Desquesnes Marc, Yangtara Sarawut, Kunphukhieo Pawinee, Chalermwong Piangjai, Jittapalapong Sathaporn, Herder Stéphane
CIRAD, UMR InterTryp, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, F-34000, France; Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand.
Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand.
Exp Parasitol. 2016 Jun;165:35-42. doi: 10.1016/j.exppara.2016.03.009. Epub 2016 Mar 14.
A growing number of atypical human infections due to the livestock parasite Trypanosoma evansi, or to the rat parasite Trypanosoma lewisi, are reported in humans in Asia. In some cases, clinical evolutions request treatments, however, so far, there were very few attempts to control T. lewisi using trypanocidal drugs. In a study published elsewhere, the efficacy of human trypanocides is evaluated in laboratory rats, and it concludes that none of them is able to cure rats experimentally infected with T. lewisi. Control of T. lewisi in rat would be a step for identification of drugs against this parasite. In the present study, 4 veterinary drugs: diminazene aceturate, isometamidium chloride, melarsomine hydrochloride and quinapyramine sulfate and chloride, were evaluated at low and high doses, in intra-muscular injections to normal rats experimentally infected with a stock of T. lewisi from Thailand. None of these treatments being efficient, a trial was also made using melarsomine hydrochloride in T. evansi infected rats and in mixed T. lewisi and T. evansi infected rats, in order to demonstrate the efficacy of the drugs under the present protocol. T. evansi was cleared from the rat's blood the day after the treatment, while, T. lewisi remained unaffected until the end of the experiment. These observations clearly demonstrated the efficacy of melarsomine hydrochloride against T. evansi and its inefficacy against T. lewisi. In conclusion none of the veterinary drugs was efficient against this stock of T. lewisi. Other protocols using higher doses or other drugs and T. lewisi stocks should be investigated in further studies. The control of T. lewisi infection in Wistar rats, using veterinary trypanocidal drugs, remains so far unsuccessful.
在亚洲，越来越多由家畜寄生虫伊氏锥虫或鼠寄生虫刘易斯锥虫引起的非典型人类感染病例被报道。在某些情况下，临床进展需要进行治疗，然而，到目前为止，使用杀锥虫药物控制刘易斯锥虫的尝试非常少。在其他地方发表的一项研究中，对人体杀锥虫药在实验室大鼠中的疗效进行了评估，得出的结论是，这些药物都无法治愈实验感染刘易斯锥虫的大鼠。控制大鼠体内的刘易斯锥虫将是鉴定针对这种寄生虫药物的一个步骤。在本研究中，对4种兽药：乙酰氨基阿维菌素、氯异喹胺、盐酸美拉索明和硫酸喹嘧胺进行了低剂量和高剂量评估，通过肌肉注射给予实验感染来自泰国的刘易斯锥虫毒株的正常大鼠。这些治疗方法均无效，还对盐酸美拉索明在感染伊氏锥虫的大鼠以及同时感染刘易斯锥虫和伊氏锥虫的大鼠中进行了试验，以证明在本方案下这些药物的疗效。治疗后一天，伊氏锥虫从大鼠血液中清除，而刘易斯锥虫在实验结束前一直未受影响。这些观察结果清楚地证明了盐酸美拉索明对伊氏锥虫有效，而对刘易斯锥虫无效。总之，没有一种兽药对这种刘易斯锥虫毒株有效。在进一步的研究中，应该研究使用更高剂量或其他药物以及不同刘易斯锥虫毒株的其他方案。到目前为止，使用兽用杀锥虫药物控制Wistar大鼠体内的刘易斯锥虫感染仍然没有成功。
