Investigating of the role of Toxoplasma gondii infection in the pathophysiology of Alzheimer's disease

Alzheimer's Disease (AD) is the most common type of dementia whose etiology and pathogenesis are not fully understood and is increasing worldwide. Toxoplasma gondii (T. gondii) is a zoonotic disease that is common in humans and animals all over the world and can infect all organs, including the brain. This work; It was conducted to investigate the risk of AD in the offspring of female rats infected with T. gondii. 2-4 months old Wistar Albino female rats were used in the study. The animals are divided into five groups of seven. Some groups of these animals were infected intraperitoneally by preparing Aβ1-42 solution 4µg/1µL/side bilaterally intrahippocampally and T. gondii RH strain 1.5x10⁶ parasite inoculum, and then mated with healthy male rats. 8 puppies were randomly selected from each mother group. Barnes maze behavior test was applied to all study groups. The differential diagnosis of the presence of Aβ clusters in the brain tissues of all animals was examined by Congo Red staining methods. All results were evaluated statistically via SPSS. Median(IQR) time for hatchlings to find the nest: control 5.75(3.55-9.02)sec., Alzheimer's 32.70(21.0-40.0)sec., T. gondii 60(16.3-60) sec., T. gondii1+Alzheimer2 50.10(33-60)sec, Alzheimer1+T. gondii2 6.10(3.3-10.07)sec. found. While there was a statistically significant difference in the detection times of the control and Alzheimer, T.gondii and T. gondii1+Alzheimer2 groups, no difference was found with the Alzheimer1+T.gondii2 group. The mother and offspring Alzheimer1+T.gondii2 group were similar to the control group. Aβ plaques were observed in the brain of offspring with congo red in 5 of 21 (23.8%) of the offspring of mothers treated with Aβ42. T.gondii infection after AH model may cause resistance of the host body against AH. KEYWORDS: Toxoplasma gondii, Alzheimer's Disease, Rat, Behavioral Test, Congo Red Staining