Localization and quantification of dystrophin in epileptic rats

Abstract

Aim: In Duchenne muscular dystrophy (DMD) populations, a higher prevalence of epilepsy has been found compared with control groups. We hypothesized that epilepsy/seizures causes loss of dystrophin in the brain. Our aim was to localize dystrophin in cerebellum and hippocampus and to develop a reliable method for quantification of dystrophin. Methods: Male adult Spraque-Dawley rats were used in a amygdala kindled model (N=24). Cerebellar and hippocampal tissue were stained immunohistochemically with anti-dystrophin, anti-calbindin, anti-GFAP and Hoechst. Anti-NeuN was only applied in hippocampal tissue. Under fluorescent microscope, pictures were taken for quantification in ImageJ. Results: Glia cells and Purkinje cells colocalized with dystrophin, however, hippocampal neuronal cells did not show a colocalization with dystrophin. Statistical analysis of the quantification of dystrophin around the Purkinje neuron, showed a high intra-observer correlation (Mean grey value: Pearson correlation (r=1,000, P<0,0001) and ICC (r=1,000, P<0,0001); Intensity density: Pearson correlation (r=0,986, P<0,000) and ICC (r=0,984, P<0,0001)). Conclusion: Dystrophin is ubiquitously expressed in the cerebellum and hippocampus, but the exact distribution of the dystrophin isoforms in these areas are not clear yet. We have developed a reliable quantification method of dystrophin around the cerebellar Purkinje cells, but not for glia cells and hippocampal neurons. Future studies should therefore not only be aimed at the distribution of the dystrophin isoforms, but also at the quantification of glia cells and hippocampal neurons.