Your browser doesn't support javascript.
loading
Langat virus infection affects hippocampal neuron morphology and function in mice without disease signs.
Cornelius, Angela D A; Hosseini, Shirin; Schreier, Sarah; Fritzsch, David; Weichert, Loreen; Michaelsen-Preusse, Kristin; Fendt, Markus; Kröger, Andrea.
Afiliação
  • Cornelius ADA; Innate Immunity and Infection, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany.
  • Hosseini S; Present Address: Institute of Virology, Hannover Medical School, 30625, Hannover, Germany.
  • Schreier S; Department of Cellular Neurobiology, Zoological Institute, TU Braunschweig, 38106, Braunschweig, Germany.
  • Fritzsch D; Neuroinflammation and Neurodegeneration Group, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany.
  • Weichert L; Institute of Medical Microbiology and Hospital Hygiene, Otto-von-Guericke University, Leipziger Strasse 44, D-39120, Magdeburg, Germany.
  • Michaelsen-Preusse K; Institute of Medical Microbiology and Hospital Hygiene, Otto-von-Guericke University, Leipziger Strasse 44, D-39120, Magdeburg, Germany.
  • Fendt M; Innate Immunity and Infection, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany.
  • Kröger A; Institute of Medical Microbiology and Hospital Hygiene, Otto-von-Guericke University, Leipziger Strasse 44, D-39120, Magdeburg, Germany.
J Neuroinflammation ; 17(1): 278, 2020 Sep 20.
Article em En | MEDLINE | ID: mdl-32951602
ABSTRACT

BACKGROUND:

Tick-borne encephalitis virus (TBEV) is an important human pathogen that can cause the serious illness tick-borne encephalitis (TBE). Patients with clinical symptoms can suffer from severe meningoencephalitis with sequelae that include cognitive disorders and paralysis. While less than 30% of patients with clinical symptoms develop meningoencephalitis, the number of seropositive individuals in some regions indicates a much higher prevalence of TBEV infections, either with no or subclinical symptoms. The functional relevance of these subclinical TBEV infections and their influence on brain functions, such as learning and memory, has not been investigated so far.

METHODS:

To compare the effect of low and high viral replication in the brain, wildtype and Irf-7-/- mice were infected with Langat virus (LGTV), which belongs to the TBEV-serogroup. The viral burden was analyzed in the olfactory bulb and the hippocampus. Open field, elevated plus maze, and Morris water maze experiments were performed to determine the impact on anxiety-like behavior, learning, and memory formation. Spine density of hippocampal neurons and activation of microglia and astrocytes were analyzed.

RESULTS:

In contrast to susceptible Irf-7-/- mice, wildtype mice showed no disease signs upon LGTV infection. Detection of viral RNA in the olfactory bulb revealed CNS infections in wildtype and Irf-7-/- mice. Very low levels of viral replication were detectable in the hippocampus of wildtype mice. Although wildtype mice develop no disease signs, they showed reduced anxiety-like behavior and impaired memory formation, whereas Irf-7-/- mice were not affected. This impairment was associated with a significant decrease in spine density of neurons in the hippocampal CA1 region of wildtype mice. Microglia activation and astrogliosis were detected in the hippocampus.

CONCLUSION:

In this study, we demonstrate that subclinical infections by viruses from the TBEV-serogroup affected anxiety-like behavior. Virus replication in the olfactory bulb induced far-reaching effects on hippocampal neuron morphology and impaired hippocampus-dependent learning and memory formation.
Assuntos
Palavras-chave

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Encefalite Transmitida por Carrapatos / Vírus da Encefalite Transmitidos por Carrapatos / Hipocampo / Neurônios Idioma: En Ano de publicação: 2020 Tipo de documento: Article

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Encefalite Transmitida por Carrapatos / Vírus da Encefalite Transmitidos por Carrapatos / Hipocampo / Neurônios Idioma: En Ano de publicação: 2020 Tipo de documento: Article