Preliminary study on the role of toll-like receptor-4 antagonist in treatment of Trichinella spiralis infection

Abstract

Background Trichinella spiralis is one of the most widespread zoonotic parasitic nematodes in the world. There is an increasing interest in developing new antihelminthic drugs for Trichinella. Toll-like receptor-4 (TLR4) is closely related to T. spiralis infection, and its deficiency is associated with rapid expulsion of T. spiralis worms. Aim The aim of this study was to explore the effect of TLR4 antagonist (curcumin) on the course of experimental trichinellosis. Materials and methods Mice were divided into two main groups. Group I was the control group (90 mice), which was subdivided into the following: subgroup Ia (10 mice), with noninfected nontreated mice (negative control); subgroup Ib (40 mice), with infected nontreated mice (positive control); and subgroup Ic (40 mice), with noninfected treated with curcumin. Group II was the infected and treated group (50 mice), where infected mice received curcumin starting 2 h after infection and continued for 10 successive days after infection. For each group, total adult and muscle larval count were estimated, and the small intestines and muscles were removed for further studies. Results This results showed a significant decrease in the mean number of adults and larvae in the infected treated group compared with the infected control mice, with an extremely significant percentage of reduction of 53%. Regarding the histopathological changes, there was a marked increase in the inflammatory reaction surrounding the adult worms in the small intestines and the encysted larvae in muscles of the infected treated group compared with the infected nontreated group. Curcumin leads to degeneration of the capsule around the larvae in the skeletal muscles of the infected treated group. There was a significant increase in nuclear factor-κB expression by small intestinal tissues in T. spiralis infected treated group (group II) as compared with the infected nontreated group (group Ib). Conclusion This study revealed that curcumin has an antiparasitic activity against both stages of T. spiralis. Thus, it could be a promising drug for treatment of T. spiralis infection.