Inhibitory effect of some new uracil and thiouracil derivatives on cercarial penetration enzymes
作者:O. A. Fathalla、M. E. Haiba、M. M. Anwar、Maha S. Almutairi、A. S. Maghraby、M. M. Bahgat
DOI:10.1007/s11164-012-0748-x
日期:2013.5
Some uracil- and thiouracil-5-sulfonohydrazide derivatives have been synthesized to be evaluated as antischistosomal agents. N-[2-(1,5-Dimethyl-3-oxo-2-phenylpyrazolin-4-yl)-4-oxo-1,3-thiazolidin-3-yl]-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-sulfonamide (3c) was formulated in jojoba oil and used to paint mice tails before infection with Schistosoma mansoni cercariae. Using Boc-Val-Leu-Gly-Arg-PNA, a specific substrate for trypsin-like serine proteinases, compound 3c inhibited cercarial serine protease activity with 50 % inhibition concentration (IC50) of 160 μg. Upon topical application on mice tails before infection with S. mansoni cercariae, it caused a 20 % reduction in worm burden compared with untreated infected mice. Using soluble crude cercarial antigen in enzyme-linked immunosorbent assay (ELISA), no significant changes were observed in the levels of immunoglobulin M (IgM) and IgG in sera from treated infected mice at 2, 4, and 6 weeks postinfection (WPI) compared with the level in sera from infected untreated mice. At 4 WPI, sera from treated infected mice showed significantly low (P < 0.05) IgM reactivity to crude soluble worm antigen compared with infected nontreated ones. IgG levels in sera from treated infected mice at 2 and 4 WPI were significantly lower (P < 0.05) than in sera from infected nontreated mice. At 6 WPI, the IgG response showed no significant differences in sera from both mice groups. Sera from treated infected mice at 2, 4, and 6 WPI had generally lower IgM reactivity to soluble egg antigen when compared with the level in sera from nontreated infected mice. At all time points postinfection, sera collected from treated infected mice showed significantly low IgG reactivity (P < 0.05) compared with infected nontreated mice.
一些尿嘧啶和硫尿嘧啶-5-磺酸肼衍生物已被合成,并被评估为抗血吸虫剂。N-[2-(1,5-二甲基-3-氧代-2-苯基吡唑啉-4-基)-4-氧代-1,3-噻唑烷-3-基]-4-氧代-2-硫代-1,2,3,4-四氢嘧啶-5-磺酰胺(3c)被配制在荷荷巴油中,并用于感染血吸虫幼虫前涂抹小鼠尾巴。利用Boc-Val-Leu-Gly-Arg-PNA,这是一种特异性基质用于类胰蛋白酶的丝氨酸蛋白酶,化合物3c对幼虫丝氨酸蛋白酶活性产生了50%的抑制浓度(IC50)为160μg。 在感染S. mansoni幼虫前的局部涂抹中,与未处理的感染小鼠相比,它使虫体负担降低了20%。 使用溶解的粗幼虫抗原进行酶联免疫吸附试验(ELISA),在感染后2、4和6周,与未处理感染小鼠的血清水平相比,未观察到治疗感染小鼠IgM和IgG水平的显著变化。 在4周时,治疗感染小鼠的血清对粗溶解虫抗原表现出明显低(P < 0.05)的IgM反应,与未处理的感染小鼠相比。 在2和4周时,治疗感染小鼠的血清IgG水平明显低(P < 0.05)于未处理感染小鼠的血清。 在6周时,两个小鼠组的血清IgG反应没有显著差异。 与未处理感染小鼠的血清水平相比,治疗感染小鼠在2、4和6周时对可溶性卵抗原的IgM反应普遍较低。 在感染后所有时间点,治疗感染小鼠收集的血清与未处理感染小鼠相比,IgG反应显著低(P < 0.05)。