Hoyu Takahashi

NACP/α-synuclein-positive filamentous inclusions in astrocytes and oligodendrocytes of Parkinson's disease brains

Abstract The precursor of the non-Aβ component of Alzheimer’s disease amyloid (NACP), also called α-synuclein, is a major component of Lewy bodies in Parkinson’s disease (PD) as well as of neuronal and oligodendroglial cytoplasmic inclusions in multiple system atrophy. We previously reported argyrophilic, tau-negative glial inclusions in the midbrains of patients with PD and have now conducted immunocytochemical and ultrastructural examinations. The PD glial inclusions also are immunoreactive for NACP/α-synuclein, but not for β-synuclein, and ultrastructurally are composed of filamentous structures about 25–40 nm in diameter. Double immunolabeling showed that the inclusions were present in both astrocytic and oligodendroglial cells. They were located within the substantia nigra in 13 of 30 patients with PD and outside the nigra in 24. The number of inclusions was correlated with the severity of nigral neuronal loss. These findings indicate that abnormal accumulation of NACP/α-synuclein in glial cells is a pathological feature of PD related to its progression.

Different histopathology accounting for a decrease in myocardial MIBG uptake in PD and MSA

Differential diagnosis between PD and multiple-system atrophy (MSA) is often difficult, especially in early disease stages. Recent studies have shown that [123I]metaiodobenzylguanidine (MIBG) myocardial scintigraphy is useful to separate PD from MSA; MIBG uptake in PD is significantly lower than in MSA.1-3⇓⇓ However, a pathophysiologic mechanism for the decrease in myocardial MIBG uptake in PD and MSA remains to be elucidated. We describe a patient with PD and a patient with MSA. Postmortem examination revealed a severe loss of myocardial sympathetic nerve fibers in the former but not in the latter. ### Patient 1. An 80-year-old woman developed bradykinesia and gait disturbance, followed by right dominant resting hand tremor and rigidity, postural instability, severe constipation, and orthostatic hypotension. Dopaminergic therapy such as levodopa/carbidopa was given and effective for bradykinesia, rigidity, and tremor. She was diagnosed as having PD at the age of 82 years. Her condition deteriorated; she occasionally experienced syncope. She died of bronchopneumonia at 84 years old. MIBG myocardial scintigraphy, at the age of 83 years, showed …

Accumulation of NEDD8 in neuronal and glial inclusions of neurodegenerative disorders

NEDD8 (neural precursor cell expressed, developmentally down‐regulated 8) is a ubiquitin‐like protein that controls vital biological events through its conjugation to members of the cullin family, which are components of certain ubiquitin E3  ligases.  Recent  studies  have  shown  that  NEDD8 is incorporated into Lewy bodies (LBs) in Parkinsons disease, Mallory bodies in alcoholic liver disease and Rosenthal fibres in astrocytoma. In order to examine whether NEDD8 plays a role in the formation of ubiquitinated inclusions, we performed immunohistochemical staining of brain tissue from patients with various neurodegenerative disorders, using an affinity‐purified polyclonal antibody raised against NEDD8 that did not cross‐react with ubiquitin. In LB disease, NEDD8 immunoreactivity was present in almost all of the LBs and Lewy neurites. Moreover, NEDD8 immunoreactivity was found in a variety of ubiquitinated inclusions, including neuronal and oligodendroglial inclusions in multiple system atrophy, neurofibrillary tangles in Alzheimers disease, ubiquitinated inclusions in motor neurone disease, and intranuclear inclusions in triplet repeat diseases. These findings suggest that NEDD8 is involved in the formation of various ubiquitinated inclusions via the ubiquitin‐proteasome system.

A Comparative Double-Blind Randomized Trial of Activated Protein C and Unfractionated Heparin in the Treatment of Disseminated Intravascular Coagulation

A randomized prospective double-blind trial was performed to compare the safety and efficacy of human activated protein C (APC) and unfractionated heparin for the treatment of disseminated intravascular coagulation (DIC). One hundred thirty-two patients with DIC were enrolled in this study: 63 patients received APC (12.5 U [2.5 μg]/kg body wt per hour) and 69 patients received heparin (8 U/kg body wt per hour) by intravenous infusion for 6 days. Forty-nine APC-treated patients and 55 heparintreated patients were evaluated for efficacy, and 52 APC-treated patients and 55 heparin-treated patients were evaluated for safety. The 2 groups were similar with respect to sex, age, body weight, underlying diseases, and coagulation/fibrinolysis parameters before treatment. Aggravation of bleeding was seen after treatment in 8 patients receiving heparin, but in none of the patients receiving APC. The number of patients who showed alleviation of bleeding was significantly higher in the APC group than the heparin group (P = .009). The effects on DIC-related organ dysfunction were not significantly different between the 2 groups. Fibrinogen-fibrin degradation products, D-dimer, thrombin-antithrombin complex (TAT), and plasmin-plasmin inhibitor complex (PIC) were all significantly decreased by treatment in both groups. Fibrinogen, protein C, and antithrombin were significantly increased in the APC group, whereas only protein C was significantly increased in the heparin group. Platelet count in the nonleukemic group was significantly increased in those patients receiving APC but not increased in those patients receiving heparin. Improvement of coagulation/ fibrinolysis was assessed by scoring 4 parameters (soluble fibrin monomers, D-dimer, TAT, and PIC), and the results indicated that the APC group showed significantly greater improvement than the heparin group (P = .046). There was, however, no significant difference in the rate of complete recovery from DIC between the 2 groups. The rate of death from any cause within 28 days after treatment was 20.4% in the APC group, significantly lower than the 40% death rate observed in the heparin group (P < .05). There were no severe adverse events in either group. These results suggest that APC in a relatively small dosage can improve DIC more efficiently than can heparin, without increasing bleeding, and may be a better alternative.

Juvenile-onset generalized neuroaxonal dystrophy (Hallervorden-Spatz disease) with diffuse neurofibrillary and lewy body pathology.

Abstract We describe an unusual case of Hallervorden-Spatz disease (HSD). After presenting with limb rigidospasticity at the age of 9 years, our patient developed progressive dementia, spastic tetraparesis and myoclonic movements, leading to akinetic mutism. He died of pneumonia at the age of 39 years. Autopsy revealed a severely atrophic brain, weighing 510 g. Histologically, there were iron deposits in the globus pallidus and substantia nigra pars reticulata, and numerous axonal spheroids throughout the brain and spinal cord. Neurofibrillary tangles were abundant in the hippocampus, cerebral neocortex, basal ganglia and brain stem. Neuritic plaques and amyloid deposits were absent. Lewy bodies and Lewy neurites, which were immunolabeled by anti-α-synuclein, were found in the brain stem, cerebral cortex and spinal gray matter. Sarkosyl-insoluble tau extracted from the temporal cortex resolved on immunoblots into three major bands of 60, 64 and 68 kDa and a minor band of 72 kDa, as reported for Alzheimer’s disease. The present case, together with a few similar cases reported previously, may represent a particular subset of neuroaxonal dystrophy, i.e., HSD associated with extensive accumulation of both tau and α-synuclein.

A quantitative investigation of neuronal cytoplasmic and intranuclear inclusions in the pontine and inferior olivary nuclei in multiple system atrophy

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease characterized by the presence of neuronal and oligodendroglial α‐synuclein aggregates. To investigate the relationship between the occurrence of neuronal cytoplasmic and intranuclear inclusions (NCIs and NNIs, respectively) and the progression of neuronal degeneration, we performed a quantitative analysis of the pontine and inferior olivary nuclei based on 14 cases of MSA. α‐Synuclein immunohistochemistry revealed that NCIs and NNIs were present in both brain nuclei in all the cases. The average incidence of NCIs in the pontine and inferior olivary nuclei was 9.1% and 25.8%, respectively, and that of NNIs was 9.2% and 9.0%, respectively. The number of NNIs was strongly correlated with that of neurones in the pontine and inferior olivary nuclei. Although the number of NCIs was not correlated with the neuronal population in both nuclei, the NCI count in patients with moderate MSA was higher than in patients with mild MSA. The NNI count was much higher than the NCI count in the pontine nucleus in four patients, and was the same in the olivary nucleus in three of the four patients. Moreover, the neuronal population in the NNI‐predominant cases was significantly higher than in the NCI‐predominant cases. These findings suggest that NCI formation is accelerated by the progression of the disease process, and that in MSA, NNI formation is an earlier phenomenon than NCI formation.

Involvement of the cerebral cortex and autonomic ganglia in Machado-Joseph disease

Abstract. Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative disorder caused by expansion of a polyglutamine tract in the disease protein. In this study of brains from four autopsied MJD patients, we have demonstrated immunohistochemically that expanded polyglutamine stretches largely accumulate as inclusions in neuronal nuclei, and less frequently are distributed in the nucleoplasm in a diffuse pattern. These nuclear abnormalities involved many neurons covering a wide range of central and peripheral nervous system regions, including the cerebral cortex, thalamus and autonomic ganglia that have been categorized previously as spared regions by conventional pathological studies. These lesions, newly recognized by polyglutamine immunohistochemistry, may be responsible for the cerebral cortical dysfunctions or autonomic abnormalities pointed out in MJD patients by the recent clinical and neuroradiological studies.

Apolipoprotein E allele-dependent antioxidant activity in brains with Alzheimer's disease.

Article abstract Thiobarbituric acid–reactive substances (TBARS), an index of lipid peroxidation, were assayed in postmortem brain. Basal TBARS levels were increased and oxidative stimulation produced more TBARS in AD relative to control brains. In addition, apolipoprotein E isoforms showed differing antioxidant activities, with E2 > E3 > E4, suggesting that the lowest antioxidant activity of E4 could contribute to its association with AD.

Immunohistochemical distribution of the two isoforms of synaphin/complexin involved in neurotransmitter release: localization at the distinct central nervous system regions and synaptic types.

The cellular and subcellular localization of the two synaphin isoforms, proteins associated with the docking/fusion complex crucial to neurotransmitter release, was studied in the rat central nervous system by using light microscopic and electron microscopic immunohistochemistry with monoclonal antibodies specific to each isoform. Synaphin 1 (complexin II) was predominantly expressed in neurons of the central nervous system regions such as cerebral cortex (the II, III and VI cortical layers), claustrum, hippocampus, entorhinal cortex, amygdaloid nuclei, substantia nigra pars compacta, superior colliculus, pontine reticulotegmental nucleus and inferior olive, whereas synaphin 2 (complexin I) was in the cerebral cortex (the IV cortical layer), thalamus, locus coeruleus, gigantocellular reticular field, cuneate nucleus and cerebellar basket and stellate cells. In some regions, including the caudate-putamen, globus pallidus, pontine reticular nucleus, cerebellar nuclei and spinal gray matter, synaphin 1 was mainly present in small or medium-sized neurons, while synaphin 2 was in large cells. Medial habenular nucleus and cerebellar granule cells showed both immunoreactivities. In the neuropil of the cerebral cortex and hippocampus, synaphin 1 expression was accentuated in the axon terminals of axospinal and axodendritic synapses, while synaphin 2 was predominant in the axon terminals of axosomatic synapses. In the axon terminals, both immunolabelings were associated with synaptic vesicles and the plasma membrane, being accentuated in the vicinity of synaptic contacts. In the cerebral cortex, both immunoreactivities were also present occasionally in dendrites and dendritic spines, associated with microtubules and the plasma membrane including the postsynaptic densities. These results suggest that the two isoforms of synaphin are involved in synaptic function at the distinct presynaptic regions in the central nervous system, and that some dendrites are another functional site for the proteins.

Fragmentation of the Golgi apparatus of the ballooned neurons in patients with corticobasal degeneration and Creutzfeldt-Jakob disease

Abstract We investigated immunohistologically the Golgi apparatus (GA) and the trans-Golgi network (TGN) of the cortical ballooned neurons (BNs) in two patients with corticobasal degeneration and in five with Creutzfeldt-Jakob disease. We observed that the BNs showed fragmentation of the GA and the TGN, accompanied by a reduction in the number of fragmented Golgi elements and by a unique perinuclear distribution. This is the first report of the abnormalities of GA in cortical BNs. These findings suggests that the GA and the TGN may play some roles in the BN formation.