Background: This study examined the acute and sub-acute toxic effects of Terminalia chebula and Achillea wilhelmsii extracts on the murine model. Methods: In both phases, mice were assigned to intervention and control groups. At the end of study, the liver, kidney, and heart tissues were collected for histopathological studies. Results: In the acute phase of the study, the safe dose was ≤5000 mg/kg for both extracts. In sub-acute phase, LD50 (95% CI) of Achillea wilhelmsii extract was determined ≥5000 mg/kg and that of Terminalia chebula extract 2754.436 (2438-3114) mg/kg. The highest dose of T. chebula extract induced few histopathological changes. Conclusion: It will be useful to gain information on the minimum lethal doses of T. chebula and A. wilhelmsii to adopt safe doses of the two plants.

Background: We examined anti-Toxoplasma effect of hydroalcoholic extract of Terminalia chebula Retz (T. chebula) in cell culture and murine model. Methods: The study was conducted in Shahrekord University of Medical Sciences, Iran in 2017. Half maximal effective (concentration (EC50) of T. chebula extract and pyrimethamine was determined in infected Hela cells by using 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) method. In the animal model, BALB/c mice were injected with tachyzoites (104) of T. RH strain intraperitoneally. 24h after the injection, the test groups were orally treated with 100, 200, 400 and 800 mg/kg of T. chebula extract for 7 days. The survival rate of the mice was determined and blood samples were collected to determine the amount of serum Malondialdehyde (MDA) and antioxidant capacity. Then peritoneal fluid of the mice was collected to count the number of tachyzoites and after necropsy, the pathologic changes, including the weight of liver, spleen and kidneys were investigated. The analysis of data was accomplished using SPSS. Results: EC50 values were 94.7μg/mL and 290.50μg/mL for T. chebula and pyrimethamine respectively. In the animal model, the extract of T. chebula in concentration of 100 mg/kg showed the same anti-Toxoplasma effect as pyrimethamine. This concentration of the extract decreased number of intraperitoneal tachyzoites and increased the survival rate of the mice. This extract reduced the levels of serum MDA and tissue inflammation and increased serum antioxidant capacity. Conclusion: Regarding the positive effect of extract, after more clinical trials in the animal model and standardization of the extract, it can be used as an alternative or complementary therapy for toxoplasmosis.