Evaluation of the prophylactic and therapeutic effects of selenium and vitamin E on the muscular phase of experimental Trichinella spiralis infection in mice.

Abstract

Trichinellosis is a foodborne parasitic infection, where the Trichinella spiralis larvae invade, grow and dwell in muscle cells, transforming them into nurse cells for nutrient supply and protective shelter. The present study evaluated the prophylactic and therapeutic impact of the antioxidants selenium (Se) and vitamin E (Vit E), alone and in combinations with albendazole (ALB), on muscular phase of experimental Trichinella spiralis infection in mice. Forty-eight Swiss albino mice were divided into 3 main groups: control, prophylactic, and therapeutic groups, with further subgrouping according to the received treatment. Larval count, inflammation around the encapsulated larvae, and oxidative stress markers were assessed. All groups receiving treatment showed a significant reduction in larvae count/gm muscle compared to the infected control group. In the prophylactic group, combined VitE-Se achieved the highest reduction, 58.4% and 51% in the diaphragm and intercostals, respectively. Whereas in the therapeutic group combined VitE-Se-ALB showed the maximum reduction rates of 90.4% and 84.4% in the diaphragm and intercostals, respectively. Varying grades of cellular inflammatory infiltration were detected around the capsule in various groups, with marked reduction in degree of inflammation in all combination groups containing ALB. Oxidative stress markers malondialdehyde (MDA) and superoxide dismutase (SOD) levels showed a significant decrease in treated muscle tissues, the lowermost level was detected in the VitE-Se-ALB combination group. In conclusion, combined Vit E-Se reduced muscle larval burden in the prophylactic group, potentiated the antiparasitic action of ALB in the therapeutic group, and demonstrated anti-inflammatory and antioxidant effects.