National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan.
Am J Trop Med Hyg. 2012 Oct;87(4):681-8. doi: 10.4269/ajtmh.2012.12-0218. Epub 2012 Aug 13.
We evaluated the inhibitory effects of pepstatin A and mefloquine on the in vitro and in vivo growths of Babesia parasites. The in vitro growth of Babesia bovis, B. bigemina, B. caballi, and B. equi was significantly inhibited (P < 0.05) by micromolar concentrations of pepstatin A (50% inhibitory concentrations = 38.5, 36.5, 17.6, and 18.1 μM, respectively) and mefloquine (50% inhibitory concentrations = 59.7, 56.7, 20.7, and 4 μM, respectively). Furthermore, both reagents either alone at a concentration of 5 mg/kg or in combinations (2.5/2.5 and 5/5 mg/kg) for 10 days significantly inhibited the in vivo growth of B. microti in mice. Mefloquine treatment was highly effective and the combination treatments were less effective than other treatments. Therefore, mefloquine may antagonize the actions of pepstatin A against babesiosis and aspartic proteases may play an important role in the asexual growth cycle of Babesia parasites.
我们评估了胃抑素 A 和甲氟喹对巴贝斯虫寄生虫体外和体内生长的抑制作用。微摩尔浓度的胃抑素 A（50%抑制浓度分别为 38.5、36.5、17.6 和 18.1 μM）和甲氟喹（50%抑制浓度分别为 59.7、56.7、20.7 和 4 μM）显著抑制了牛巴贝斯虫、双芽巴贝斯虫、马巴贝斯虫和犬巴贝斯虫的体外生长。此外，两种试剂单独以 5 mg/kg 的浓度或在 10 天内以组合（2.5/2.5 和 5/5 mg/kg）的方式使用均显著抑制了小鼠体内微小巴贝斯虫的生长。甲氟喹治疗非常有效，联合治疗不如其他治疗有效。因此，甲氟喹可能拮抗胃抑素 A 对巴贝斯虫病的作用，天冬氨酸蛋白酶可能在巴贝斯虫寄生虫的无性生长周期中发挥重要作用。
