RESUMO
Objective To investigate the effect of glucose metabolism alteration induced by alloxan intraventricular injection on learning and memory abilities of mice, and its role in the development of AD. Methods Mice were randomly divided into high-dose alloxan intraventricular injection group (n=7, 4 mg/kg) and low-dose alloxan intraventricular injection group (n=7, 1.5 mg/kg)and control group (n=7, physiological saline); intraventricular injection of alloxan, the O-GLcNAc transferase inhibitor, was performed in the high-dose and low-dose alloxan intraventricular injection groups to interfere the brain glucose metabolism. Morris water maze was used to detect the learning and memory abilities of mice. Western blotting and immunohistochemistry were used to analyze the alterations of phosphorylation and O-Glycosylation of neurofilament in mice brain induced by alloxan intraventricular injection. Results In the located navigation tests, the swimming time and distance to find the platform in the mice of alloxan administration were significantly increased as compared with those in the control group (P＜ 0.05); in space exploration experiments, compared with those in the control mice, the number of crossing the hidden platform was decreased and the initial angle of entry to water was increased in the mice of alloxan administration (P＜0.05). Western blotting and immunohistochemistry displayed that phosphorylation was obviously increased and the O-Glycosylation was significantly reduced in the cytoskletal neurofilament of the mice with alloxan administration as compared with those in the control group (P＜0.05), which was similar to the alteration of neurofilament's modification in AD brain. Conclusion The inventricular injection of alloxan could impair the learning and memory of mice, which might have a relation with the dysregulation of phosphorylation and O-Glycosylation in neurofilament caused by the impaired glucose metabolism, which is similar to the alteration of phosphorylation and O-Glycosylation in neurofilament in AD brain.