ABSTRACT
BACKGROUND Behavioral and neurochemical alterations associated with toxoplasmosis may be influenced by the persistence of tissue cysts and activation of an immune response in the brain of Toxoplasma gondii-infected hosts. The cerebral extracellular matrix is organised as perineuronal nets (PNNs) that are both released and ensheath by some neurons and glial cells. There is evidences to suggest that PNNs impairment is a pathophysiological mechanism associated with neuropsychiatric conditions. However, there is a lack of information regarding the impact of parasitic infections on the PNNs integrity and how this could affect the host's behavior. OBJECTIVES In this context, we aimed to analyse the impact of T. gondii infection on cyst burden, PNNs integrity, and possible effects in the locomotor activity of chronically infected mice. METHODS We infected mice with T. gondii ME-49 strain. After thirty days, we assessed locomotor performance of animals using the open field test, followed by evaluation of cysts burden and PNNs integrity in four brain regions (primary and secondary motor cortices, prefrontal and somesthetic cortex) to assess the PNNs integrity using Wisteria floribunda agglutinin (WFA) labeling by immunohistochemical analyses. FINDINGS AND MAIN CONCLUSIONS Our findings revealed a random distribution of cysts in the brain, the disruption of PNNs surrounding neurons in four areas of the cerebral cortex and hyperlocomotor behavior in T. gondii-infected mice. These results can contribute to elucidate the link toxoplasmosis with the establishment of neuroinflammatory response in neuropsychiatric disorders and to raise a discussion about the mechanisms related to changes in brain connectivity, with possible behavioral repercussions during chronic T. gondii infection.
Subject(s)
Animals , Mice , Cerebellum/metabolism , Toxoplasmosis/pathology , Toxoplasmosis, Animal , Extracellular Matrix/metabolism , Motor Neurons/cytology , Neurons/pathology , Toxoplasma , Cerebellum/cytology , Toxoplasmosis/metabolism , Disease Models, Animal , Motor Neurons/metabolism , Neurons/metabolismABSTRACT
BACKGROUND: Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA-M2BP) is a protein with altered glycosylation that reacts with lectin, and was recently identified as a useful non-invasive biomarker for the diagnosis of liver fibrosis in patients with hepatitis C virus infection.This study aimed to evaluate the diagnostic efficacy of WFA-M2BP for liver fibrosis in the context of hepatitis B virus (HBV). METHODS: We enrolled 151 patients infected with HBV. Liver biopsy and elastography (Fibroscan) were performed during the initial visit. Fibrosis was graded according to the Knodell histologic activity index (F0–3). WFA-M2BP levels were determined with an automated immunoassay analyzer (M2BPGi, HISCL-5000, Sysmex, Japan). The diagnostic efficacy of WFA-M2BP was compared with those of various conventional or composite biomarkers, including enhanced liver fibrosis (ELF) score, Fibroscan, aspartate transaminase (AST)-to-platelet ratio index (APRI), and FIB-4, based on the area under the ROC curve (AUC) value. RESULTS: The majority of patients were at fibrosis stages F1 and F2. The F2 and F3 AUC values for WFA-M2BP were similar to those for FIB-4, APRI, ELF, and Fibroscan, although the latter showed the best diagnostic efficacy. The diagnostic accuracy of all tested biomarkers for F2 and F3 was 60–70%. In multivariate analysis, WFA-M2BP, ELF, and platelet count significantly predicted stage ≥F2, whereas only platelet count significantly predicted F3. CONCLUSIONS: WFA-M2BP can support a diagnosis of liver fibrosis with similar diagnostic efficacy to other biomarkers, and predicted liver fibrosis stage ≥2 among patients with chronic hepatitis B.