Features of NeuN Expression in the Cingulate Cortex of the Cerebral Hemispheres of Mice After Administration of Escherichia Coli Lipopolysaccharide

Abstract

The aim was to observe changes in NeuN expression in the cingulate cortex of the cerebral hemispheres of mice after intraperitoneal administration of various doses of bacterial lipopolysaccharide (LPS). Material and methods. The study was conducted on 12 C57Bl/6 mice, which were injected intraperitoneally at the same time for 4 days with saline (control group) or E. coli LPS in one of the following doses: 0.5 mg/kg/day (1st group), 1 mg/kg/day (2nd group) or 2 mg/kg/day (3rd group). Brain sampling was performed in animals and histological preparations with a 5 µm thickness were made and stained with antibodies to the NeuN. The number of NeuN-expressing cells in the cingulate cortex of the cerebral hemispheres, in the Cg1 area/dorsal anterior cingulate cortex, was counted. The data were also statistically processed. Results. In immunohistochemical study, the number of neurons expressing NeuN in the 1st group (LPS at a dose of 0.5 mg/kg/day) was 8226.9±336.94 cells per 1 mm2, in the 2nd group (LPS at a dose of 1 mg/kg/day) – 7889.4±211.83 cells per 1 mm2, in the 3rd group (LPS at a dose of 2 mg/kg/day) – 7039.7±580.42 cells per 1 mm2, in the control group – 9985.6±576.75 cells per 1 mm2. Immunofluorescent study revealed no difference between the samples. Conclusion. When LPS is administered intraperitoneally to mice for 4 days at doses of 0.5–2 mg/kg/day, the expression of NeuN, a marker of mature neurons, decreases. The data obtained can be used to create a model of age-related neurodegeneration.