title: Changes in neurotransmitter levels and expression of immediate early genes in brain of mice infected with Neospora caninum.
abstract: Neospora caninum is an obligate intracellular parasite that causes neurological disorders in dogs and cattle. The majority of host animals are asymptomatic at the chronic stage of infection. However, it remains unclear whether cerebral function is normal in asymptomatic animals. In this study, mice were infected with N. caninum (strain Nc-1) and their brains were examined to understand changes in cerebral function at the chronic stage of infection. Mice infected with N. caninum showed impaired locomotor activity, but no differences in clinical symptoms were observed. In the brains of infected mice, parasites were distributed throughout the brain and histological lesions were observed everywhere except for the cerebellum. Expression levels of proinflammatory cytokines, interferon-gamma and tumour necrosis factor-alpha, were highly upregulated in several brain regions of infected mice. Additionally, the level of neurotransmitters glutamate, glycine, gamma-aminobutyric acid, dopamine and 5-hydroxytryptamine, were altered in infected mice compared with those of uninfected mice. Interestingly, the expression levels of immediately early genes, c-Fos and Arc, in the brain of infected mice were lower than those of in uninfected mice. Our findings may provide insight into neurological disorders associated with N. caninum infection.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Ihara
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Nishimura
authors.affiliation: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Yoshikage
authors.initials: Y
authors.lastname: Muroi
authors.affiliation: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Furuoka
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yokoyama
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Nishikawa
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D002522:Chlorocebus aethiops; D002851:Chromatography, High Pressure Liquid; D003048:Coccidiosis / Q000235:genetics / Q000378:metabolism* / Q000469:parasitology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006790:Host-Parasite Interactions; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism*; D018836:Inflammation Mediators / Q000378:metabolism; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000235:genetics / Q000502:physiology; D018688:Neospora / Q000502:physiology; D018377:Neurotransmitter Agents / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D014709:Vero Cells
chemical_list: D016207:Cytokines; D017874:Immediate-Early Proteins; D018836:Inflammation Mediators; D018377:Neurotransmitter Agents; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma