Fasciola gigantica: Evaluation of the effect of phenyl vinyl sulfone in vitro

Evaluation of the ovicidal activity and fasciolicidal activity of the extract of ethyl acetate from Artemisia ludoviciana Nutt. spp. mexicana and of artemisinin against adult parasites of Fasciola hepatica

The objective of this work was to evaluate the effect of the ethyl acetate extract from A. ludoviciana (EALM) and artemisinin against adult parasites and eggs of F. hepatica. For the ovicidal assay, cell culture plates with 24 wells were used, and 90 to 110 F. hepatica eggs were placed in each well. The eggs were exposed to concentrations of 100, 200, 300, 400, and 500 mg/L EALM and incubated for 16 days. Additionally, triclabendazole (TCBZ) was used as a reference drug at concentrations of 10 and 50 mg, and the response of artemisinin at concentrations of 10 and 20 mg was simultaneously assessed. Adult flukes were exposed to concentrations of 125, 250, 375, and 500 mg/L EALM. The results of the ovicidal action of EALM on the eggs showed that concentrations greater than 300 mg/L were significant, with ovicidal percentages greater than 60% observed on day 16 of incubation (p < 0.05). The maximum efficiency of EALM on adult flukes was reached 72 h post-exposure at a concentration of 125 mg/L (p < 0.05).

Effect of phenyl vinyl sulphone cysteine protease inhibitor on Schistosoma mansoni: in vitro and in vivo experimental studies

The present work aimed to study the effect of phenyl vinyl sulphone (PVS), a CPI, on different stages of Schistosoma (S.) mansoni in an in vitro culture study and in experimentally infected mice, compared to PZQ. As regards the in vitro study, different concentrations of PVS (1, 2, 4, 6, 8 and 10 µg/ml) and PZQ (1 µg/ml) were assessed by % worm mortality for schistosomula and adults, and hemoglobin degradation by schistosomula. In vivo study included 8 groups of mice. Intraperitoneal PVS, subgroup (a), and oral PZQ, subgroup (b), were assessed at different durations post infection (pi); at 1, 3, 5 and 7 weeks pi (groups I, II, III and IV, respectively). Infection, PVS, PZQ, and normal control groups (groups V-VIII) were included. The anti-schistosomal effects of PVS were assessed by parasitological, histopathological and haematological parameters. In in vitro study, PVS had a schistosomicidal effect in a concentration and time dependent manner, PVS showed 100% schistosomula mortality at day 2 and 92% adult worm mortality at day 5. Furthermore, PVS decreased hemoglobin degradation by schistosomula. In in vivo study, PVS showed a decrease in total worm burden and tissue egg load in intestine and liver with an increase in number of dead ova in intestine of mice. Furthermore, PVS resulted in a decrease in number, size and cellularity of hepatic granulomas and an increase in hemoglobin concentration.PVS was better than PZQ in reducing each of tissue egg count in intestine at 5 and 7 weeks pi, and hepatic granuloma size at 3, 5 and 7 weeks pi. These results suggest that PVS can be a promising chemotherapeutic agent in Schistosoma mansoni infection.

Regioselective synthesis and ab initio calculations of fused heterocycles thermally and under microwave irradiation

Pyrazolo[1,5-a]pyrimidine, triazolo[1,5-a]pyrimidine, and pyrimido[1,2-a]benzimidazole, pyrido[1,2-a]benzimidazole ring systems incorporating phenylsulfonyl moiety were synthesized via the reaction of 3-(N,N-dimethylamino)-1-(thiophen-2-yl)-2-(phenylsulfonyl)prop-2-en-1-one derivatives with the appropriate aminoazoles as 1,3-binucleophiles and 1H-benzimidazol-2-ylacetonitrile using conventional methods as well as microwave irradiation. The regioselectivity of the cyclocondensation reactions was confirmed both experimentally by alternative synthesis of reaction products and theoretically using ab initio quantum chemical calculations namely the Density Functional Theory (DFT). The theoretical work was carried out using the Becke, three parameter, Lee-Yang-Parr hybrid functional (B3LYP) combined with the 6-311++G(d,p) basis set. It was found that the final cyclocondensation reaction product depends mainly on the initial addition to the activated double bond by the nitrogen atom of the 1,3-binucleophiles that has the higher electron density.