The effect of Nigella sativa oil- and wheat germ oil-loaded metal organic frameworks on chronic murine toxoplasmosis

Abstract

Treatment of chronic toxoplasmosis is challenging as the available drugs are effective only in the acute stage. Therefore, the current study aimed to investigate Nigella sativa oil (NSO) and wheat germ oil (WGO) loaded on copper-benzene tricarboxylic acid metal organic framework (Cu-BTC MOF) for treating chronic toxoplasmosis in a murine model. Eighty mice were divided into 8 groups (G); uninfected untreated negative control (GI), infected untreated positive control (GII), infected and treated with: Spiramycin (GIII), Spiramycin@Cu-BTC (GIV), Cu-BTC (GV), WGO@Cu-BTC (GVI), NSO@Cu-BTC (GVII) and combined WGO+NSO@Cu-BTC (GVIII). The infected groups were orally inoculated with 10 Toxoplasma gondii Me49 strain cysts/mouse. All drugs were orally administered for 14 consecutive days starting 8 weeks post-infection (wpi). The therapeutic efficacy was evaluated by parasitological (survival rate of mice and brain cyst burden) and histopathological (brain, liver, kidney, eye) parameters. At the end of 2-weeks therapy, the highest therapeutic outcome was achieved with GVII and GVIII exhibiting 100% survival, 64.3% and 51.4% reduction of brain cysts, and an apparent amendment of pathological insults. In the next place was GVI with 90% survival, 49.5% reduction of cysts and marked amelioration of pathological lesions. Meanwhile, GIII and GIV showed 80% survival, 42.4% and 41.8% reduction of cysts as well as minimal to moderate alleviation of tissue damage. The lowest effect was obtained with GV resulting in 70% survival and 24.4% reduction of cysts. The current results support the assertion that the new metal-based nanocomposites can be promising remedies of chronic toxoplasmosis particularly if conjugated with natural herbal extracts as NSO and WGO.

Keywords: Metal organic frameworks; Nanocomposites; Nigella sativa; Spiramycin; Toxoplasma gondii; Wheat germ.