Prophylactic effect of the anti-inflammatory drug diclofenac in experimental schistosomiasis mansoni.

OBJECTIVES: This study was a trial to demonstrate the prophylactic effect of diclofenac, a widely used anti-inflammatory drug (diclofenac potassium, CAS-15307-81-0, Ciba Geigy, 334.2) in experimental schistosomiasis mansoni. Two different dose regimens were used to explore the effects upon worm load, tissue egg load, and hepatic granuloma size. METHODS: In this study, a group of 50 Swiss albino mice was used. This group was divided into five subgroups: subgroup I constituted infected untreated control mice; subgroup II, infected mice given 0.5 mg diclofenac orally 24 h post infection, then sacrificed three weeks later; subgroup III, infected mice given 0.5 mg diclofenac orally six weeks post infection and sacrificed one week later; subgroup IV, infected mice administered 1mg diclofenac orally 24 h post infection and sacrificed three weeks later; and subgroup V, infected mice given 1mg of the drug orally six weeks post infection and sacrificed one week later. RESULTS: Mice given the high dose regimen (1mg orally/mouse) 24 h post infection, then sacrificed three weeks later, demonstrated a significant reduction in the immature worms recovered, compared to the untreated controls. Animals receiving the high dose of the drug six weeks post infection, then sacrificed one week later, revealed a drop in the number of mature worms and in the tissue egg load (hepatic and intestinal), and the smallest hepatic granuloma measurement compared to the untreated controls. These findings were less conspicuous in animals given the low dose regimen. CONCLUSION: Diclofenac could be used successfully as a preventive agent against schistosomiasis mansoni infection in endemic areas.

Effect of simultaneous and/or consecutive administration of the broad spectrum anthelmintic flubendazole together with praziquantel in experimental Schistosoma mansoni infection.

This study is a trial to demonstrate the effect of the broad spectrum anthelmintic drug flubendazole (methyl 5-(p-fluoro-benzoyl)-2-benzimidazolecarbamate, CAS 31430-15-6), a mebendazole derivative, together with praziquantel (CAS 55268-74-1, EMBAY 8440, Biltricide) in murine schistosomiasis mansoni. Moreover, the relationship between the posttreatment worm burden, oogram pattern, tissue egg load and hepatic granuloma volume was also investigated. Three main groups of Swiss albino mice infected with Schistosoma mansoni cercariae were used in the experiment. Group I included infected untreated control mice. Group II: Subgroup II (a): Animals received 1/3 the dose of praziquantel 25 days post infection. Subgroup II (b): Mice were given 1/3 dose of flubendazole 25 days post infection. Subgroup II (c): Animals received the combination (1/3 dose of flubendazole + 1/3 the dose of praziquantel 25 days post infection. Group III: Subgroup III (a): Mice were given 1/3 the dose of praziquantel 7 weeks post infection. Subgroup III (b): Mice received 1/3 dose of flubendazole 25 days post infection. 24 days later, 1/3 the dose of praziquantel was given. Mice given the consecutive drug regimen (flubendazole 1/3 single oral dose 25 days post infection, then praziquantel 1/3 oral dose for two successive days 24 days later, revealed a significant reduction in the recovery of adult schistosomes after portal perfusion (95.9%), absence of immature stages of ova development, a higher level of dead ova in the oogram and the smallest granuloma mean diameter. These data were less conspicuous in mice given the simultaneous drug regimen.

Treatment of acute schistosomiasis mansoni with praziquantel and an antifibrotic agent in mice. Maintenance of resistance to infection.

This work is a trial to evaluate the effect of the combination of the anthelmintic drug praziquantel (CAS 55268-74-1, PZQ, EMBAY 8440, Biltricide) with the antifibrotic agent beta-aminopropionitrile-monofumarate salt (BAPN, CAS 2079-89-2). It is also a trial to elucidate the repercussions of this drug combination upon worm and tissue egg loads and oogram pattern. Moreover, it aims to study their effects on the hepatic granuloma size and the resistance to reinfection in experimental murine schistosomiasis mansoni. A group of 120 Swiss albino mice was used. This group was further subdivided into six small subgroups. Subgroup I comprised infected untreated control mice. Subgroup II comprised infected untreated challenged control mice. Subgroup III comprised challenged control mice. Subgroup IV comprised infected mice treated with PZQ 500 mg/kg b. w. orally for two successive days. Subgroup V comprised infected mice given BAPN daily as 5 mg powder in 0.5 ml saline for 14 successive days. Subgroup VI comprised mice given both PZQ + BAPN. Animals were sacrificed 12 weeks post primary infection. Mice given the combination regimen PZQ + BAPN, compared to those given each drug solely, revealed absence of worm recovery at perfusion and only dead ova in the oogram (99.2 + 0.6). Inspite of the marked reduction in the hepatic and intestinal tissue egg loads recorded, this drug combination revealed the highest score of percent resistance to reinfection (91.2 + 0.5%). The data were less salient in mice given PZQ or BAPN alone.