Intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies in myotonic dystrophy: a quantitative morphological study

Abstract

Intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies have been studied in four patients with myotonic dystrophy (MyD), eight patients with other neurological diseases (control A), and eight patients without neurological diseases (control B). The percentages of the affected cells were calculated by dividing the number of neurons including intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies, by the total cell count in these respective regions. Statistical analyses were performed with regard to the frequency of these bodies by using Student's t test. There was a significantly higher incidence of intracytoplasmic inclusion bodies of the thalamus (13.2% versus 0.7%, P less than 0.001) and the substantia nigra (20.4% versus 2.7%, P less than 0.001), and Marinesco bodies (37.4% versus 4.1%, P less than 0.001) in patients with MyD than in controls A and B. From our observations, it is suggested that the presence with a high frequency, in combination, of these bodies is not an incidental finding but may have an intimate and important relationship with the pathogenesis of MyD, and may be a conspicuous and diagnostically important feature of MyD.

Cerebral involvement in myotonic dystrophies

“…Neuronal eosinophilic inclusion bodies have been described in early studies 80 in a relatively large proportion of the thalamic nuclei (up to 30%) of patients with DM1, similar to findings in primary progressive neurodegenerative disorders. These observations were confirmed by other authors, 86 although their clinical significance is still unclear.…”

“…These observations were confirmed by other authors, 86 although their clinical significance is still unclear. Not only the thalamus but also the substantia nigra 80 and caudate nucleus 86 may be involved. More recently, immunostaining of the inclusions has demonstrated that they are composed of ubiquitin and microtubule-associated proteins, thus creating the neuropathological substrate for including myotonic dystrophies amongst the neurodegenerative disorders.…”

Functional MRI changes in the central motor system in myotonic dystrophy type 1

“…Brain changes in DM1 both in the adult (mild and classic) and congenital form have been documented by neuropathological, neuroradiological and neurophysiological studies [11][12][13][14][15][16][17][18][19][20][21][22][23][24], which have shown changes in cortical and subcortical structures. Most of these changes are similar to those seen in normal aging, and they have contributed to the classification of DM1 among the progeric diseases.…”

Muscleblind-Like 1 Knockout Mice Reveal Novel Splicing Defects in the Myotonic Dystrophy Brain

“…CNS involvement in adult-onset DM1 includes visual spatial and attention deficits, dysexecutive syndrome, apathy, avoidant behavior and excessive daytime sleepiness (review [1]). Although neuropathological studies have revealed several morphological changes [2], [3], [4], whether these changes contribute to the clinical symptoms observed in DM1 remains to be determined.…”