In vitro effect of praziquantel and albendazole combination therapy on the larval stage of Echinococcus granulosus

Abstract

Protoscolices of Echinococcus granulosus were incubated in vitro with praziquantel (PZ), albendazole (ABZ), or a combination of both (PZ + ABZ). PZ and ABZ displayed slower protoscolicidal activity when applied separately than when used in combination. Despite the low PZ + ABZ concentrations used, protoscolex viability dropped rapidly (within 15 days). At this time, cysts did not develop following their inoculation into mice. The ultrastructural changes induced in the protoscolices by PZ + ABZ were (a) the loss of sucker concavity, (b tegumental contraction of the soma region, (c) the formation of digitiform tegumental extensions, (d) destruction of the tegument, and (e) the degeneration of parenchyma cells as reflected by the presence of numerous lamellar bodies. The PZ + ABZ treatment was effective only against small cysts, which had collapsed at 10 days postinoculation (p.i.). This treatment caused the following alterations: (a) loss of cyst turgidity at 6 days p.i.; (b) separation of the laminated and germinal layers; (c) loss of microtriches; (d) the appearance of numerous lipid droplets in the inner region of the germinal layer, (e) vacuolation of the cyton cytoplasm; and (f) the formation of abundant autophagosomes, which finally led to loss of the integrity of the germinal layer.

Efficacy of Cyperus Rotundus Rhizomes-Tubers Extracts Against Protoscoleces of Echinococcus Granulosus

“…The present results agree with Xing et al, [55] whom mentioned that the tegument of the protoscolecs was the primary site of damage and showed ultrastructural alterations when it treated with sodium arsenite in vitro and reasoned it as stress responses. In comparition to treatment with benzimidazole-methylcarbamate compounds which bind to parasite B-tubulin and this disrupts the tubulin microtubule dynamic equilibrium which lead to reduction in [59] which generate metabolic and structural alteration in the parasite leading to its death.…”

“…In addition large number of important enzymes is anchored in the tegument. [53] The change in the protoscoleces included tegumental alteration, rostellar disorganization, loss of rostellum hooks, followed by the formation of numerous blebs on the tegument, previously the same finding was observed in the protoscoleces cultured in the presence of various chemical substances Praziquantel and albendazole combination [54] , flubendazole [40] , thymol [22] nitazoxanide [5] , sodium arsenite [55] and carvacrol. [56] It would appear logical to assume that loss of hooks and formation of blebs are "stress response" brought about in protoscoleces by any harmful condition.…”

“…[55] In addition, Singh et al, [64] concluded that the ethanolic extract of C.rotundus rhizomes was safe and no mortality occurred in the Albino mice up to dose 2000mg/kg without any toxicity. Beside the confirmation that C. rotundus is believed safe for human use.…”

Viability loss and ultrastructural changes on protoscolices of human hydatid cysts induced by retinoic acid

“…This was confirmed by morphological and ultrastructural deformities induced by the two effective atRA doses at different incubation periods. Such atRA-induced morphological and ultrastructural changes that included contraction in soma region, formation of blebs on the tegument, rosteller disorganization, loss of hooks, and destruction of microtriches were consistent with that observed with several established protoscolicidal compounds including praziquantel (Urrea-Parıis et al, 1999, 2000, benzimidazole (Pe´rez-Serrano et al, 2001), albendazole (Ceballos et al, 2011) and ivermectin (Casado et al, 1989;Elissondo et al, 2009).…”

Osmoregulatory and tegumental ultrastructural damages to protoscoleces of hydatid cysts Echinococcus granulosus induced by fungal endophytes

“…3 The tegumental digitiform extensions observed at the outer tegument of protoscoleces treated by fungal (Eupenicillium) extract observed by the treatment with extract of Eupenicillium sp. shows contraction in soma region, abnormality in sucker areas, formation of blebs on the tegument, rosteller cone disorganization, shedding of hooks and microtriches, very similar to synthetic drugs such as praziquantel Urrea-París et al 1999, 2000, benzimidazole Pérez-Serrano et al 2001), and ivermectin .…”