In Vitro and in Vivo Evaluation of the Effect of Egyptian Propolis on Experimental Trichinellosis in Mice

Background Trichinellosis is a widespread zoonosis for which no fully effective treatment is yet available. Propolis is a natural, safe, resinous substance with known pharmacological properties such as anti-inflammatory, antimicrobial, immunomodulatory, antioxidant, antifibrotic, anticancer, antifungal and antiparasitic activities. Objectives: aiming to evaluate the effect of Egyptian propolis ethanolic extract on Trichinella spiralis adult and muscle larva both in vitro and in vivo. Patients and Methods: In vitro study included adult worms and muscle larvae, isolated from mice, and incubated in RPMI-1640 medium. Three groups for both adults (A) and muscle larvae (M); Groups I (Gr.IA & Gr.IM: infection control, solvent control and albendazole-treated), Groups II (Gr.IIA & Gr.IIM: Propolis extract-treated group with different concentrations (0.5 to 20 mg/mL)) and Groups III (Gr.IIIA & Gr.IIIM: Combination of both albendazole and propolis extract-treated group). Mortality rate was calculated, and structural changes of the cuticle was evaluated using SEM. In vivo study (Mice (n=160)) included four groups; GI: (normal healthy, infected control, albendazole-treated), GII: Propolis extract-treated (250mg/kg/d), GIII: treated with a combination of both albendazole and propolis extract, GIV: Propolis extract given as prophylaxis. Total adult and larval burden in intestine and muscles, biochemical, histopathology, and immunohistochemistry assessments were done. Results:_Propolis extract showed potent lethal effect, in a dose and time-dependent manner, on both adult and muscle larva during in vitro culture with LD90 after 24h were 2.58 mg/mL and 58 mg/mL, respectively. SEM showed that propolis extract exerted detrimental changes in the cuticle of the incubated adult worms and larvae. In vivo results showed a statistically significant reduction in the mean adult and larval burden, marked improvement of biochemical parameters, reduced inflammation, and fibrosis in intestinal and muscle specimens with lowered pro-apoptotic BAX protein expression especially when combined with albendazole. Conclusion: Propolis extract is a promising prophylactic and effective anthelminthic alternative.