Background: Toxoplasmosis treatment with the current gold standard combination of pyrimethamine
and sulfadiazine or triple sulphonamides, is associated with adverse side effects. There is an urgent need
to investigate new natural products with high efficacy and minimum side effects.
Objective: To evaluate the therapeutic potential of neem oil against experimental acute toxoplasmosis.
Material and Methods: Four hours after infection with T. gondii (RH strain) tachyzoites, mice were treated
with neem oil extract, and its efficacy was compared versus Septrin (trimethoprim-sulfamethoxazole).
Parasitological evaluation included tachyzoite counts in the peritoneal fluid, splenic and hepatic tissue,
as well as survival time. Tachyzoites ultrastructural alterations were recorded using both scanning
and transmission electron microscope (SEM, and TEM). Immunological study was also conducted by
assessment of serum IFN-ɣ level.
Results: Treatment improved the outcome of infection as the mice survival time reached 9.7±1.4 days
with reduction in tachyzoites load and viability reaching 77.6% and 44.4%, respectively. Histopathological
examination of hepatic and splenic tissue sections showed less lymphocyte infiltration, less necrosis with
scanty free tachyzoite in the section. Compared to Septrin-treated mice, IFN-ɣ level showed significant
rise.
Conclusion: Neem oil extract is a potential therapeutic agent against acute toxoplasmosis.