Inducible Nitric Oxide Synthase is required for parasite restriction and inflammatory modulation during Neospora caninum infection

Publication date: Available online 16 November 2019Source: Veterinary ParasitologyAuthor(s): Patrício da Silva Cardoso Barros, Caroline Martins Mota, Vanessa dos Santos Miranda, Flávia Batista Ferreira, Eliézer Lucas Pires Ramos, Silas Silva Santana, Lourenço Faria Costa, Ana Cláudia Arantes Marques Pajuaba, José Roberto Mineo, Tiago Wilson Patriarca MineoAbstractNeospora caninum infection is an important cause of neuromuscular disease in dogs and abortion in cattle, leading to significant economic losses in beef and dairy industries. The protective immunity against apicomplexan parasites, specifically Toxoplasma gondii and N. caninum, is typically achieved by inducing an IL-12-driven Th1 immune response. IL-12 stimulates IFN-γ production, which activates Inducible Nitric Oxide Synthase (iNOS) and promotes consequent Nitric Oxide (NO) synthesis, classically described as one of the main effector mechanisms for parasite elimination. Here, we aimed to evaluate the role played by iNOS during N. caninum infection. Our results show that N. caninum infection in C57BL/6 wild type (WT) mice induce NO production in vivo and in vitro. In agreement, iNOS deficient mice, as well as WT mice treated with iNOS inhibitor aminoguanidine, succumbed during acute infection with a dose lethal to 50% of the WT mice, and presented significant increase in parasite load when submitted to sub-lethal infection protocols. Interestingly, the lack of control of parasite proliferation observed in iNO...
Source: Veterinary Parasitology - Category: Veterinary Research Source Type: research