Masanori Tomonaga

Apolipoprotein E immunoreactivity in cerebral amyloid deposits and neurofibrillary tangles in Alzheimer's disease and kuru plaque amyloid in Creutzfeldt-Jakob disease

During the course of our immunohistochemical studies on the change of lipids in Alzheimers disease brains by using antibody to apolipoprotein E, a protein having a special relevance to nervous tissue, we unexpectedly found that apo E immunoreactivity was associated with amyloid in both senile plaques and cerebral vessels and neurofibrillary tangles. The immunoreactivity was also found in amyloid of kuru plaques in Creutzfeldt-Jakob disease. Pretreatment of the sections with formic acid greatly enhanced immunoreactivity of senile and kuru plaques to antibody to apo E.

The growth inhibitory factor that is deficient in the Alzheimer's disease brain is a 68 amino acid metallothionein-like protein

We have purified and characterized the growth inhibitory factor (GIF) that is abundant in the normal human brain, but greatly reduced in the Alzheimers disease (AD) brain. GIF inhibited survival and neurite formation of cortical neurons in vitro. Purified GIF is a 68 amino acid small protein, and its amino acid sequence is 70% identical to that of human metallothionein II with a 1 amino acid insert and a unique 6 amino acid insert in the NH2-terminal and the COOH-terminal portions, respectively. The antibodies to the unique sequence of GIF revealed a distinct subset of astrocytes in the gray matter that appears to be closely associated with neuronal perikarya and dendrites. In the AD cortex, the number of GIF-positive astrocytes was drastically reduced, suggesting that GIF is down-regulated in the subset of astrocytes during AD.

Rapid appearance of β-amyloid precursor protein immunoreactivity in damaged axons and reactive glial cells in rat brain following needle stab injury

Brains of rats that had received needle stab wounds were examined sequentially for 72 h by immunohistochemistry using antibodies to beta-amyloid precursor protein (APP). Immunoreactivity appeared 0.5 h after the injury in axons adjacent to the needle tract, becoming stronger over 15 h in neighboring swollen axons. APP-immunoreactive glial cells appeared 6 h after the injury around the needle tract and persisted throughout the experiment. Morphologically, these cells were thought to be mainly astrocytes.

Neurotrophic action of Alzheimer's disease brain extract is due to the loss of inhibitory factors for survival and neurite formation of cerebral cortical neurons.

Cell cultures of neonatal rat cerebral cortex in a serum-free medium were used to investigate whether specific neurotrophic factors are accumulated or inhibitory factors for neuronal survival and neurite formation decrease in AD brain extract. Neurotrophic activity in brain extract was quantified by using the ELISA for microtubule-associated protein 2 (MAP2). Inhibitory factors, which blocked neurotrophic activity, were present in normal brain extract. In AD brain extract, loss of the inhibitory factors resulted in a relative increase in neurotrophic activity. The inhibitory factors in normal brain extract were retained on the ultrafiltration membrane with molecular weight cutoff of 10 kDa.

Alzheimer's disease brain extract stimulates the survival of cerebral cortical neurons from neonatal rats.

Cell cultures of neonatal rat cerebral cortex in a serum-free medium were used to investigate a lack of neuronotrophic factors in Alzheimers disease (AD) brain. A few neurons survived in the absence of brain extract. The addition of normal brain extract resulted in a 2.5-fold increase in neuronal survival. AD brain extract contained 4-fold neuronotrophic activity of normal brain extract. These findings are in contrary to the previous hypothesis of a lacking neuronotrophic factors in AD brain. These new results may change the concept of mechanism of neuronal death in AD.

Clinicopathologic study of progressive subcortical vascular encephalopathy (Binswanger type) in the elderly.

A clinicopathologic study was made of 45 elderly persons whose autopsied brains showed the pathologic changes of progressive subcortical vascular encephalopathy (Binswanger type). Progressive subcortical vascular encephalopathy (PSVE) was observed in 3.8 per cent of all autopsied brains of elderly persons and in 6.7 per cent of the brains of those with cerebrovascular diseases. White matter lesions were graded from I to III (slight to severe). Small infarcts in the basal ganglia, thalamus, and pons were common, but the cerebral cortex was usually preserved. Neuropsychiatric symptoms included dementia, urinary incontinence, hemiplegia, pseudobulbar palsy, psychosis, parkinsonism, and mutism. In the Grade III group there was a high incidence of pseudobulbar palsy, parkinsonism, and mutism. Pathologic study showed marked cerebral arteriosclerosis in almost all cases. Angionecrosis was observed in 60 to 80 per cent. Fibrotic and stenotic changes of the blood vessels in the deep white matter were also noted, particularly in 90 per cent of the Grade III cases. A suggested explanation for the pathogenesis of PSVE is based on the effects of various complications such as hypertension, cardiac disease and malnutrition which may play an important role in PSVE when they occur in elderly persons with a history of longstanding hypertension, marked cerebral arteriosclerosis, and arteriolar changes in the cerebral white matter.

Immunocytochemical and ultrastructural study of Lewy body-like hyaline inclusions in familial amyotrophic lateral sclerosis

SummaryLewy body-like hyaline inclusion (LI) in the neuronal soma and swollen cord-like processes is a characteristic feature in the anterior horn cells and neurons in thoracic nucleus (Clarke) of familial amyotrophic lateral sclerosis (ALS) with posterior column involvement. We have studied the LI in the case of two sisters with this disorders. Microscopically the LI consists of an eosinophilic “core” surrounded by a basophilic “halo”. Ultrastructurally the core consists of granule-associated filaments, while the halo consists of normal-looking neurofilament. Immunocytochemistry with anti-ubiquitin antibody shows that these granule-associated filaments in the core are highly ubiquitinated, while the normal-looking neurofilaments in the halo are not recognized by antiubiquitin antibody. Our study proves that LI consists of an aggregation of ubiquitinated filaments among a neurofilamentous accumulation, possibly representing a form of neuronal cytoskeletal disorganization in familial ALS.

Presenile appearance of abundant Alzheimer's neurofibrillary tangles without senile plaques in the brain in myotonic dystrophy.

SummaryIn 7 myotonic dystrophy (MyD) cases of 35-to 56-year old and 18 non-neurological age-matched controls paraffin-embedded temporal lobe sections were stained by the modified Bielschowsky method to count neurofibrillary tangles (NFTs) and senile plaques (SPs). In the parahippocampal gyrus, NFTs were observed in all the MyD cases; a few in the youngest, with an increase in number with age to the abundant appearance in the 4 cases in their 50s. The eldest also had many NFTs in the hippocampus. By contrast, the control subjects had, if any, only a few NFTs in the hippocampus and the parahippocampal gyrus. No SPs were observed in any NFTs appear, unaccompanied by SPs, at an abnormally early age in the parahippocampal gyrus, with a rapid age-related increase in their number. This neuronal change may belong to the progeric features observed in this condition.

Ultrastructure of the Bunina bodies in anterior horn cells of amyotrophic lateral sclerosis.

SummaryLight and electron microscopic studies were made on the anterior horn cells in a case of amyotrophic lateral sclerosis. Eosinophilic inclusions of Bunina type were observed almost selectively in the motor neurons of spinal cord, as well as of brain stem, at the light microscopic level. Fine structural study revealed the presence of two types of cytoplasmic inclusions. The first, mainly corresponding to the light microscopic inclusions, were homogeneous, electron-dense, round- or oval-shaped bodies with vesicular or tubular rims and ribosome particles, about 2–5 μ in diameter, which contained filaments or other cytoplasmic components in the clear areas within them. The second were lamellar structures (laminated cytoplasmic bodies, Morales) which appeared to be originating from endoplasmic reticulum. There was no distinct transition in these two types of inclusions and the relationship to each other is not clear. The significance of Bunina body is unknown, but some manifestation of a primary disorder, e.g., protein metabolism, rather than a secondary degenerative change in the motor neurons in amyotorophic lateral sclerosis.

Neuropathology of the locus ceruleus: a semi-quantitative study

SummaryThe locus ceruleus was studied in 86 brains of the elderly, with or without degenerative disease. Parkinsons disease, multiple system atrophy, progressive supranuclear palsy and senile dementia were among the diseases studied. Nerve cell loss, the appearance of neurofibrillary changes and Lewy bodies were examined semi-quantiatively. The number of nerve cells diminished in old age, especially over 90 years. The decrease of nerve cells was greater in cases with Lewy bodies. A marked loss of nerve cell was observed in multiple system atrophies, including Shy-Drager syndrome, olivopontocerebellar atrophy and striatonigral degeneration, and in some cases of Parkinsons disease and senile dementia. The number of nerve cells did not decrease in cases of progressive supranuclear palsy. Lewy bodies and neurofibrillary tangles appeared increasingly in old age. However, the incidence of both changes in the same neuron was rare, and in such cases their structures appeared not to be related.ZusammenfassungEs wurden 24 Hirne von Individuen von über 60 Jahren untersucht sowie 22 Gehirne von Patienten mit Parkinsonscher Krankheit, multipler Systematrophie, seniler Demenz, progressiver supranukleärer Lähmung etc. Es wurden semiquantitative Untersuchungen über die Anzahl der Nervenzellen und das Auftreten der Neurofibrillenveränderungen und Lewyschen Körperchen im Locus ceruleus angestellt.1. Die Durchschnittszahl der Nervenzellen im Locus ceruleus bei 60 Individuen von über 60 Jahren war geringer als jene bei 12 jüngeren Fällen. Besonders deutlich waren die zahlenmäßige Abnahme in den Fällen von über 90 Jahren. Das Volumen der Nervenzellen an Serienschnitten zeigte in den Fällen von über 80 Jahren einen Verlust von ca. 40%.2. Der Verlust an Nervenzellen war besonders ausgeprägt bei jenen Fällen, die auch Lewy-Körperchen zeigten.3. Ein besonders hochgradiger Verlust an Nervenzellen wurde in den Fällen mit multiplen Systematrophien, zum Beispiel Shy-Drager-Syndrom, olivo-ponto-cerebelläre Atrophie und striato-nigraler Degeneration sowie in einigen Fällen der Parkinsonschen Krankheit und senilen Demenz festgestellt. Andererseits war die Zahl der Nervenzellen in drei Fällen von progressiver supranukleärer Lähmung nicht vermindert.4. Im hohen Alter waren die Lewyschen Körperchen und die Veränderungen der Neurofibrillen besonders ausgeprägt. Hingegen war das gleichzeitige Vorhandensein beider Veränderungen in ein und derselben Nervenzelle sehr selten und wenn dies einmal zusammen vorhanden war, war keine strukturelle Beziehung zwischen den zwei Veränderungen vorhanden.