title: Toxoplasma gondii Infection Potentiates Cognitive Impairments of Alzheimer's Disease in the BALB/c Mice.
abstract: This study tests the hypothesis that in chronic Toxoplasma gondii infection communication among immune cells promotes neuroinflammation through cytokine networks and potentiate cognitive impairments in BALB/c mice with Alzheimer's disease (AD). The animal model of Toxoplasma infection was established by the intraperitoneal inoculation of 20-25 tissue cysts from the Tehran strain of T. gondii . We injected amyloid-beta 1-42 peptide (Aβ1-42, 1 and 2 μl) into the hippocampus of BALB/c mice to establish an animal model of AD. The behavioral experiments such as spatial learning and memory were performed using the Morris water maze test. The mRNA levels of TNF-α, IL-1β, IFN-γ, and inducible nitric oxide synthase (iNOS) were examined by real-time PCR. We found that T. gondii infection caused AD-like symptoms and impaired learning and memory functions of the infected BALB/c mice. We also found that in Toxoplasma infection + Aβ1-42(1 μl) group, T. gondii infection could potentiate AD in infected mice receiving subdoses of Aβ1-42(1 μl) and caused considerable impairment in learning and memory functions similar to AD group. Comparison of the results demonstrated that mRNA levels of IL-1β, TNF-α, IFN-γ, and iNOS significantly (P < 0.001) increased in T. gondii + Aβ1-42(1 μl) in comparison with the other tested groups. The obtained results showed that chronic T. gondii infection communication among immune cells promotes neuroinflammation through cytokine networks and induces pathological progression of AD in the mice brain, whereas the presence of neuroanatomical Toxoplasma tissue cysts in the brain could also affect the behavioral functions in T. gondii -infected mice.
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Hossein
authors: H
authors: Mahmoudvand
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Vahid
authors: V
authors: Sheibani
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Saeideh
authors: S
authors: Shojaee
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Seyed Reza
authors: SR
authors: Mirbadie
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Hossein
authors: H
authors: Keshavarz
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Khadijeh
authors: K
authors: Esmaeelpour
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Ali Reza
authors: AR
authors: Keyhani
authors: Department of Medical Parasitology and Mycology, Lorestan University of Medical Sciences, Khorramabad, Iran.
authors: Naser
authors: N
authors: Ziaali
mesh_terms: D000544:Alzheimer Disease / Q000209:etiology*; D016229:Amyloid beta-Peptides / Q000008:administration & dosage / Q000009:adverse effects; D000818:Animals; D001921:Brain / Q000473:pathology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D006624:Hippocampus / Q000187:drug effects / Q000469:parasitology; D008297:Male; D018782:Maze Learning; D008568:Memory; D051379:Mice; D008807:Mice, Inbred BALB C; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction; D065853:Spatial Learning; D065852:Spatial Memory; D013550:Swimming; D014124:Toxoplasmosis, Animal / Q000150:complications*
chemical_list: D016229:Amyloid beta-Peptides; D016207:Cytokines; D012333:RNA, Messenger; D052247:Nitric Oxide Synthase Type II