β-Glucan ameliorates anxiety-like behavior in mice chronically infected with the Toxoplasma gondii Wh6 strain.

Chronic Toxoplasma gondii (T. gondii) infection has been revealed to be a risk factor for neuropsychiatric diseases, including anxiety. However, there is no intervention strategy. The present study aimed to investigate the protective effect of β-glucan on T. gondii Wh6 strain-induced anxiety-like behavior in mice. The anxiety mouse model was established by infection with 10 cysts of the T. gondii Wh6 strain. β-Glucan was intraperitoneally administered 2 weeks before infection. Open field and elevated plus maze tests were performed to assess anxiety-like behavior. In the open field test, Wh6-infected mice spent less time in the central zone and had fewer entries into the central zone. In the elevated plus maze test, the infection reduced the frequency and time of head entries in the open arms. These results showed that Wh6 causes anxiety-like behavior in mice. Interestingly, the administration of β-glucan significantly ameliorated anxiety-like behavioral performance. The present study shows that β-glucan can alleviate the anxiety-like behavior induced by chronic T. gondii infection in mice, which indicates that β-glucan may be a potential drug candidate for treating T. gondii-related mental disorders, including anxiety.