Morphological characteristics of the myocardium against the background of the altered content of the immune cells in the brain in mice of different strains with experimental parkinsonism

Abstract

The aim – to investigate the features of structural changes in the myocardium in mice of different H-2 genotypes (human HLA analogue) with an experimental toxic model of parkinsonism against the background of changes in the content of lymphocytes and macrophages in the brain.
Materials and methods. Adult (6-7 months of age) male mice of the FVB/N (genotype H-2q) and 129/Sv (genotype H-2b) strains were injected once with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at a dose of 30 mg/kg (research groups) or 0.9 % sodium chloride solution (control groups). In 18 days after injections, histological examination of the myocardium, immunophenotyping of brain cells for markers CD3 and CD11b were performed in mice of all experimental groups as well as the activity of intracellular myeloperoxidase (MPO) as a marker of the brain inflammatory process was assessed.
Results and discussion. After the administration of MPTP in the myocardium of the 129/Sv mice strain we have observed death of the cardiomyocytes with the appearance of adipose tissue and areas of sclerosis, the development of inflammation with signs of lymphocytic and macrophage infiltration as well as activation of fibroblasts and destructive changes in the blood vessel wall with the destruction of the endothelial cell monolayer. After MPTP administration in the myocardium of FVB/N mice strain we have observed cardiomyocyte death, accumulation of lymphocytes and fibroblasts and areas of fat embolism in the blood vessels. In mice of the 129/Sv strain, which were MPTP injected, the content of CD3+CD11b+ cells has been higher than in the control group mice. In research group of the FVB/N mice, the content of not only CD3+CD11b+ cells, but also CD3+ cells has exceeded the values ​​of the indicators in the control animal group. After the injection of MPTP, the activity of MPO in the brain of the 129/Sv mice has been significantly higher than in control animals, but did not change in mice of the FVB/N strain.
Conclusions. In mice with a toxic model of parkinsonism, we have observed the myocardial damage, the manifestations and severity of which largely depended on the H-2 genotype of animals and peculiarities of accumulation of the immune system cells in this organ. We have established the differences in the balance of neuro-inflammatory marker cells (T lymphocytes, macrophages) as well as in the activity of the inflammatory marker MPO in the brain of research mice with different genotypes H-2. The experimental toxic model of parkinsonism may be useful for studying the development of combined myocardial pathology in parkinsonism involving immune system cells.