Search

Aims: Synaptic dysfunction in Parkinson's disease is caused by propagation of pathogenic alpha-synuclein between neurons. Previously, in multiple system atrophy (MSA), pathologically characterised by ectopic deposition of abnormal alpha-synuclein predominantly in oligodendrocytes, we demonstrated that the occurrence of memory impairment was associated with the number of alpha-synuclein-positive neuronal cytoplasmic inclusions (NCIs) in the hippocampus. In the present study, we aimed to investigate how abnormal alpha-synuclein in the hippocampus can lead to memory impairment., Methods: We performed pathological and biochemical analyses using a mouse model of adult-onset MSA and human cases (MSA, N = 25; Parkinson's disease, N = 3; Alzheimer's disease, N = 2; normal controls, N = 11). In addition, the MSA model mice were examined behaviourally and physiologically., Results: In the MSA model, inducible human alpha-synuclein was first expressed in oligodendrocytes and subsequently accumulated in the cytoplasm of excitatory hippocampal neurons (NCI-like structures) and their presynaptic nerve terminals with the development of memory impairment. alpha-Synuclein oligomers increased simultaneously in the hippocampus of the MSA model. Hippocampal dendritic spines also decreased in number, followed by suppression of long-term potentiation. Consistent with these findings obtained in the MSA model, post-mortem analysis of human MSA brain tissues showed that cases of MSA with memory impairment developed more NCIs in excitatory hippocampal neurons along with alpha-synuclein oligomers than those without., Conclusions: Our results provide new insights into the role of alpha-synuclein oligomers as a possible pathological cause of memory impairment in MSA.

Posttranslational modifications by phosphorylation, ubiquitination, neddylation and other pathways have emerged as major regulators of cellular functions. NEDD8 ultimate buster 1, NUB1, is an adaptor protein, which negatively regulates the levels of the ubiquitin‐like protein NEDD8 as well as neddylated proteins through proteasomal degradation. We previously reported that NUB1 is highly involved in the pathogenesis of synucleinopathy including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). In general, since phosphorylation is strongly related to the alteration of protein propensity, we examined if the fundamental function of NUB1 can be modulated by its phosphorylation. We created a series of phosphomimic mutants of NUB1. Among them, we found that phosphorylation of NUB1 at S46 (P‐NUB46) efficiently degrades aggregates using a cell‐based assay. Immunohistochemical studies have shown that specific antibodies against P‐NUB46 reacted with Lewy bodies in PD and DLB but not with glial cytoplasmic inclusions in MSA. Moreover, P‐NUB46 levels were significantly higher in the brains of patients with DLB than in control brains, and P‐NUB46 was extracted in an insoluble fraction of DLB. These findings suggest that the phosphorylation of NUB1 is modulated during the pathological process of Lewy body disease.

Phosphorylated transactivation response DNA-binding protein 43 kDa (p-TDP-43)-immunoreactive neuronal and glial cytoplasmic inclusions are a histopathological hallmark of sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with TDP-43. We report an autopsy case of lower motor neuron-predominant ALS in a 47-year-old Japanese man who committed suicide 5 months after onset. Histopathologically, neuronal loss was restricted to the anterior horn of the spinal cord, and no obvious neuronal loss was noted in the motor cortex or brainstem motor nuclei. Bunina bodies were found in the spinal anterior horn cells and the facial and hypoglossal nuclei. Immunohistochemically, p-TDP-43-immunoreactive neuronal, but not glial, cytoplasmic inclusions were frequently found in the spinal anterior horn and facial and hypoglossal nuclei, and rarely in the motor cortex. We considered the present case to be an example of lower motor neuron-predominant ALS. p-TDP-43-immunoreactive aggregates in neurons, but not in glial cells, may be an early-stage pathology of ALS.

AIMS: There are regional differences in the patient characteristics, management, and outcomes of hospitalized patients with heart failure (HF). The aim of this study was to evaluate the clinical characteristics and outcomes of Japanese patients who are hospitalized with HF on the basis of the left ventricular ejection fraction (LVEF) stratum. METHODS AND RESULTS: We retrospectively conducted a multicentre cohort study of 1245 hospitalized patients with decompensated HF between 2013 and 2014. Of these patients, 36% had an LVEF < 40% [HF with reduced ejection fraction (HFrEF), median age 72 years, 71% male], 21% had an LVEF 40-49% [HF with mid-range EF (HFmrEF), 77 years, 56% male], and 43% had an LVEF ≥ 50% [HF with preserved EF (HFpEF), 81 years, 44% male]. The primary outcome was death from any cause, and the secondary outcomes were cardiac death and re-hospitalization due to worsened HF after hospital discharge. There were high proportions of non-ischaemic cardiomyopathy (32%) in HFrEF patients, coronary artery disease (44%) in HFmrEF patients, and valvular disease (39%) in HFpEF patients. The frequencies of intravenous diuretic and natriuretic peptide administration during hospitalization were 66% and 30%, respectively. The median hospital stay for the overall population was 19 days, and the length of stay was >7 days for >90% of patients. In-hospital mortality was 7%, but was not different among the LVEF groups (HFrEF 7%, HFmrEF 6%, and HFpEF 8%). After a median follow-up of 19 months (range, 3-26 months), 192 (17%) of the 1156 patients who were discharged alive died, and 534 (46%) were re-hospitalized after hospital discharge. There were no significant differences in mortality after hospital discharge among the three LVEF groups (HFrEF 18%, HFmrEF 16%, and HFpEF 16%). There were no differences in cardiac death or re-hospitalization due to worsened HF after hospital discharge among the LVEF groups (cardiac death: HFrEF 8%, HFmrEF 7%, and HFpEF 7%; re-hospitalization due to worsened HF: HFrEF 19%, HFmrEF 16%, and HFpEF 17%). Multivariable-adjusted analyses showed that the HFmrEF and HFrEF groups, compared with the HFpEF group, were not associated with an increased risk for in-hospital death or death after hospital discharge. Non-cardiac causes of death and re-hospitalization after hospital discharge accounted for 35% and 38%, respectively. CONCLUSIONS: Our results revealed different clinical characteristics but similar mortality rates in the HFrEF, HFmrEF, and HFpEF groups. The most common cause of death and re-hospitalization after hospital discharge was HF, but non-cardiac causes also contributed to their prognosis. Integrated management approaches will be required for HF patients. peerReviewed

The pathological hallmark of multiple system atrophy (MSA) is fibrillary aggregates of α‐synuclein (α‐Syn) in the cytoplasm and nucleus of both oligodendrocytes and neurons. In neurons, α‐Syn localizes to the cytosolic and membrane compartments, including the synaptic vesicles, mitochondria, and endoplasmic reticulum (ER). α‐Syn binds to vesicle‐associated membrane protein‐binding protein B (VAPB) in the ER membrane. Overexpression of wild‐type and familial Parkinson's disease mutant α‐Syn perturbs the association between the ER and mitochondria, leading to ER stress and ultimately neurodegeneration. We examined brains from MSA patients (n = 7) and control subjects (n = 5) using immunohistochemistry and immunoelectron microscopy with antibodies against VAPB and phosphorylated α‐Syn. In controls, the cytoplasm of neurons and glial cells was positive for VAPB, whereas in MSA lesions VAPB immunoreactivity was decreased. The proportion of VAPB‐negative neurons in the pontine nucleus was significantly higher in MSA (13.6%) than in controls (0.6%). The incidence of cytoplasmic inclusions in VAPB‐negative neurons was significantly higher (42.2%) than that in VAPB‐positive neurons (3.6%); 67.2% of inclusion‐bearing oligodendrocytes and 51.1% of inclusion‐containing neurons were negative for VAPB. Immunoelectron microscopy revealed that α‐Syn and VAPB were localized to granulofilamentous structures in the cytoplasm of oligodendrocytes and neurons. Many vesicular structures labeled with anti‐α‐Syn were also observed within the granulofilamentous structures in the cytoplasm and nucleus of both oligodendrocytes and neurons. These findings suggest that, in MSA, reduction of VAPB is involved in the disease process and that vesicular structures are associated with inclusion formation., Reduction of VAPB is involved in the disease process of MSA. Vesicular structures are associated with inclusion formation in MSA.

Globular glial tauopathy (GGT) is a group of 4-repeat tauopathies characterized by widespread globular glial inclusions (GGIs). GGT is now classified into three subtypes based on the distribution and morphology of the GGIs. We report an autopsy case of GGT in an 85-year-old woman who presented with semantic dementia, a rare phenotype in GGT. Postmortem examination revealed marked atrophy of the frontotemporal and motor cortices and corticospinal tract degeneration with widespread occurrence of globular neurofibrillary tangles and GGIs. The distribution of the pathology was similar to that seen in GGT type III. However, the morphology of astrocytic inclusions in the present case differed from that in type III. Moreover, the tau burden in the primary motor area was more severe in the gray than in the white matter, and globular oligodendroglial inclusions were more numerous than astrocytic inclusions, corresponding to GGT type II. By contrast, the tau pathology in the temporal lobe was chiefly globular oligodendroglial inclusions in the white matter, corresponding to GGT type I. Thus, the present case exhibited a combination of GGT types I and II pathology. Our findings appear to extend the pathological heterogeneity of GGT.

Sporadic amyotrophic lateral sclerosis (sALS) is characterized pathologically by loss of upper and lower motor neurons with occurrence of transactivation response DNA-binding protein 43 kDa (TDP-43)-immunoreactive skein-like and round hyaline inclusions. Lewy body-like hyaline inclusions (LBHIs) are also found in a small proportion of sALS cases as well as in individuals with familial ALS with mutations in the Cu/Zu superoxide dismutase (SOD1) gene. LBHIs in sALS are immunopositive for TDP-43, but not for SOD1. The occurrence of Bunina bodies (BBs) is another key pathological feature of sALS. BBs are immunonegative for TDP-43 but immunopositive for cystatin C, transferrin, peripherin and sortilin-related receptor CNS expressed 2 (SorCS2). Despite differences between BBs and TDP-43 inclusions in terms of protein constituents and ultrastructure, the two inclusions are known to be linked. We recently encountered a case of sALS of 10 months duration in which many round hyaline inclusions, LBHIs and BBs were found in the anterior horn cells of the spinal cord. Our immunohistochemical and ultrastructural examinations revealed the presence of BBs within the skein-like and round hyaline inclusions, and in the LBHIs. Colocalization of BB-related proteins (cystatin C, transferrin and SorCS2) and TDP-43 was also confirmed in the halo of LBHIs as well as in the marginal portion of the skein-like and round hyaline inclusions. These findings suggest that there is some relationship between BBs and TDP-43-immunoreactive inclusions in terms of their formation processes.

The accumulation of abnormal α-synuclein is the major histopathological feature of Lewy body disease and multiple system atrophy (MSA), which are referred to as synucleinopathies. Cytoplasmic degradation systems, such as the autophagy-lysosome and proteasome pathways, are involved in their pathogenesis. Autophagy is tightly regulated by several upstream proteins including UNC-51-like kinase 1/2, beclin1, vacuolar protein sorting-associated protein 34 and autophagy/beclin1 regulator 1 (AMBRA1). Recently, we revealed that both cortical and brainstem-type Lewy bodies were immunopositive for several upstream proteins of autophagy. Therefore, we conducted the present study to elucidate the role of upstream proteins of autophagy in the pathogenesis of MSA. Pathological and biochemical analyses using human brain samples revealed that AMBRA1 is a component of the pathological hallmarks of MSA and upstream proteins of autophagy are impaired in the MSA brain. In vitro and in vivo analyses revealed a ninefold stronger affinity of AMBRA1 with α-synuclein phosphorylated at serine 129 compared with non-phosphorylated α-synuclein. Furthermore, a weak but significant correlation between AMBRA1 overexpression and reduction of abnormal α-synuclein was observed. Silencing AMBRA1 function caused aggregates of α-synuclein in the cytoplasm of mouse primary cultured neurons, which was simulated by the treatment of Bafilomycin, an autophagy inhibitor. Our results demonstrated for the first time that AMBRA1 is a novel hub binding protein of α-synuclein and plays a central role in the pathogenesis of MSA through the degradative dynamics of α-synuclein. These results raise the possibility that molecular modulation targeting AMBRA1 can be a promising candidate for the treatment of synucleinopathies.

We report the occurrence of neuronal cytoplasmic inclusions (NCIs) in the external cuneate nucleus of humans. The NCIs appeared as accumulations of eosinophilic rod-like structures in the neuronal somata in 20 (9.5%) of 211 consecutive autopsy cases. Histochemically, the NCIs were stained bright red with Gomori trichrome, Azan-Mallory and methyl green-pyronin, indicating that they contain protein and RNA. Immunohistochemically, the NCIs were positive for stress granule marker proteins, including Hu-antigen R, eukaryotic translation initiation factor 3 and poly(A)-binding protein 1, but negative for ubiquitin- and autophagy-related proteins. Ultrastructurally, the NCIs were composed of randomly oriented arrays of parallel fibrillar crystalline material with a well-defined substructure consisting of longitudinal striations, and were often associated with ribosome-like granules. These NCIs are morphologically, immunohistochemically and topographically distinct from any other inclusions previously described. Their incidence was found to increase with age. A high incidence was also observed in individuals with noninfectious inflammatory disease. These findings suggest that eosinophilic NCIs in the external cuneate nucleus are novel inclusions and might be formed under stress conditions.

Accumulation of phosphorylated α-synuclein in neurons and glial cells is a histological hallmark of Lewy body disease (LBD) and multiple system atrophy (MSA). Recently, filamentous aggregations of phosphorylated α-synuclein have been reported in the cytoplasm of Schwann cells, but not in axons, in the peripheral nervous system in MSA, mainly in the cranial and spinal nerve roots. Here we conducted an immunohistochemical investigation of the cranial and spinal nerves and dorsal root ganglia of patients with LBD. Lewy axons were found in the oculomotor, trigeminal and glossopharyngeal-vagus nerves, but not in the hypoglossal nerve. The glossopharyngeal-vagus nerves were most frequently affected, with involvement in all of 20 subjects. In the spinal nerve roots, Lewy axons were found in all of the cases examined. Lewy axons in the anterior nerves were more frequent and numerous in the thoracic and sacral segments than in the cervical and lumbar segments. On the other hand, axonal lesions in the posterior spinal nerve roots appeared to increase along a cervical-to-sacral gradient. Although Schwann cell cytoplasmic inclusions were found in the spinal nerves, they were only minimal. In the dorsal root ganglia, axonal lesions were seldom evident. These findings indicate that α-synuclein pathology in the peripheral nerves is axonal-predominant in LBD, whereas it is restricted to glial cells in MSA.

Autophagy is associated with the pathogenesis of Lewy body disease, including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). It is known that several downstream autophagosomal proteins are incorporated into Lewy bodies (LBs). We performed immunostaining and Western blot analysis using a cellular model of PD and human brain samples to investigate the involvement of upstream autophagosomal proteins (ULK1, ULK2, Beclin1, VPS34 and AMBRA1), which initiate autophagy and form autophagosomes. Time course analysis of cultured cells transfected with flag-α-synuclein and synphilin-1 revealed upregulation of these upstream proteins with accumulation of LB-like inclusions. In human specimens, only mature LBs were positive for upstream autophagosomal proteins. Western blotting of fractionated brain lysates showed that upstream autophagosomal proteins were detected in the soluble and insoluble fraction in DLB, corresponding to the bands of phosphorylated α-synuclein. However, Western blot analysis of total brain lysates in PD and DLB showed that the increase of upstream autophagosomal proteins was only partial. The quantitative, qualitative and locational alteration of upstream autophagosomal proteins in the present study indicates their involvement in the pathogenesis of LB disease. Our data also suggest that misinduction or impairment of upstream autophagy might occur in the disease process of LB disease.

The histological hallmark of multiple system atrophy (MSA) is accumulation of phosphorylated α-synuclein in oligodendrocytes. However, it is uncertain whether phosphorylated α-synuclein accumulates in astrocytes of MSA patients. We immunohistochemically examined the frontal and temporal lobes, basal ganglia, cerebellum, brainstem and spinal cord of patients with MSA (n = 15) and Lewy body disease (n = 20), and also in control subjects (n = 20). Accumulation of abnormally phosphorylated and aggregated α-synuclein was found in subpial and periventricular astrocytes in six of the 15 patients with MSA (40%). The structures were confined to the subpial surface of the ventro-lateral part of the spinal cord and brainstem, as well as the subependymal region of the lateral ventricles. They were not visualized by Gallyas-Braak staining, and were immunonegative for ubiquitin and p62. Immunoelectron microscopy revealed that the phosphorylated α-synuclein-immunoreactive structures in astrocytes were non-fibrillar and associated with granular and vesicular structures. The extent of phosphorylated α-synuclein-immunoreactive astrocytes was correlated with disease duration. No such structures were found in Lewy body disease or controls. Accumulation of phosphorylated α-synuclein can occur in subpial and periventricular astrocytes in patients with MSA, especially in those with a long disease duration.

G protein-coupled receptor 26 (GPR26) is one of the G-protein-coupled receptors (GPCRs), which comprise the largest family of membrane proteins and mediate most of the physiological responses to hormones, neurotransmitters and environmental stimulants. Although GPCRs are considered to play an important role in the pathophysiology of neurodegenerative disorders, it is uncertain whether GPR26 is involved in the pathogenesis of polyglutamine and intranuclear inclusion body diseases. We immunohistochemically examined the brain tissues of patients with four polyglutamine diseases (Huntington's disease, dentatorubral-pallidoluysian atrophy, and spinocerebellar ataxia types 1 and 3) and intranuclear inclusion body disease, and normal control subjects. In controls, anti-GPR26 antibody immunolabeled the neuronal cytoplasm in a diffuse granular pattern. Neuronal nuclear inclusions in polyglutamine diseases were immunopositive for GPR26. In intranuclear inclusion body disease, GPR26-positive nuclear inclusions were found in both neurons and glial cells. Marinesco bodies in aged control subjects were also positive for GPR26. Double immunofluorescence analysis revealed co-localization of GPR26 with polyglutamine or ubiquitin in these nuclear inclusions. These findings suggest that GPR26 may have a common role in the formation or degradation of intranuclear inclusions in several neurodegenerative diseases.

Nuclear receptor subfamily 4, group A, member 3 (NR4A3), also known as neuron-derived orphan receptor-1, is a nuclear receptor which plays key roles in cell cycle, neuronal differentiation, apoptosis and metabolism. These processes may be involved in the pathogenesis of certain neurodegenerative diseases. Previous studies have shown that there are high levels of NR4A3 mRNA in the CNS. Moreover, NR4A2, a transcription factor with homology to NR4A3, has been reported to contribute to the pathogenesis of Parkinson's disease. However, it is uncertain whether NR4A3 is also involved in diseases such as dementia with Lewy bodies, multiple system atrophy, and other neurodegenerative disorders such as tauopathies, TDP-43 proteinopathies and polyglutamine diseases. In the present study we used immunohistochemistry to examine the brain and spinal cord from patients with various neurodegenerative diseases and normal control subjects using two polyclonal anti-NR4A3 antibodies. In controls, the cytoplasm of neurons and glial cells was faintly immunostained with anti-NR4A3 antibodies. In tissues from patients with neurodegenerative diseases, immunoreactivity for NR4A3 was observed in cortical and brainstem-type Lewy bodies in Parkinson's disease and in dementia with Lewy bodies, as well as in neuronal and glial cytoplasmic inclusions in multiple system atrophy. A double-labeled immunofluorescence study showed co-localization of NR4A3 and phosphorylated α-synuclein in these inclusions. Neuronal and glial inclusions in other neurodegenerative disorders were NR4A3 negative. These findings suggest that accumulation of NR4A3 is specific to α-synucleinopathy.

Polymicrogyria (PMG) is a complex malformation accompanied with abnormal cortical laminations (two-, four- or six-layered cortex), and horizontally oriented myelinated fiber layer is evident in four-layered PMG in older individuals. Here we report a 65-year-old man with refractory epilepsy, in whom postmortem examination revealed four-layered PMG in the left hemisphere. We carried out a histological and immunohistochemical study to clarify the nature of the myelinated band in four-layered PMG cortex. The myelinated band contained no or only few neurons. GFAP- and aquaporin-1-immunoreactive astrocytes were found in the subcortical white matter as well as in the myelinated band. By contrast, GFAP- and aquaporin-1-immunoreactive astrocytes were not found in the band of Baillarger. These findings suggest that the myelinated band in PMG cortex is not the band of Baillarger and that the immunohistochemical characteristics of astrocytes in the myelinated band in PMG cortex are similar to those of the subcortical white matter. Previous studies suggest that PMG is not a cell migration disorder but a post-migration malformation. Taken together, it is likely that the myelinated band in PMG cortex represents abnormality of axonal growth or myelination after migration has terminated.

Isopentenyl diphosphate isomerase (IDI) is a cytoplasmic enzyme involved in the biosynthesis of isoprenoids including cholesterols. IDI has two isoforms in humans: IDI1 and IDI2. Since lipids are known to be a component of Lewy bodies (LBs), we investigated the immunohistochemical localization of IDI1 and IDI2 in the brain of patients with LB disease and multiple system atrophy (MSA) and normal control subjects. In normal controls, the cytoplasm of neurons was weakly immunostained with anti-IDI1 and anti-IDI2 antibodies throughout the nervous system. In LB disease, brainstem-type LBs were strongly positive for IDI1 and IDI2, and cortical LBs were unstained or barely immunolabeled. Double immunofluorescence staining revealed co-localization of phosphorylated α-synuclein with IDI1 or IDI2. Glial cytoplasmic inclusions in MSA were unstained. Previous studies have shown that levels of cholesterol metabolites are increased in the cerebral cortex of patients with LB disease, and that these metabolites accelerate α-synuclein aggregation. The present findings suggest that IDI1 and IDI2 may be associated with the production of cholesterol metabolites in neurons, leading to α-synuclein aggregation during the process of LB formation.

In Lewy body disease (LBD) such as dementia with LBs and Parkinson's disease, several lines of evidence show that disrupted proteolysis occurs. p62/SQSTM1 (p62) is highly involved with intracellular proteolysis and is a component of ubiquitin-positive inclusions in various neurodegenerative disorders. However, it is not clear whether p62 deficiency affects inclusion formation and abnormal protein accumulation. To answer this question, we used a mouse model of LBD that lacks p62, and found that LB-like inclusions were observed in transgenic mice that overexpressed α-synuclein (Tg mice) with or without the p62 protein. p62 deficiency enhanced α-synuclein pathology with regard to the number of inclusions and staining intensity compared with Tg mice that expressed p62. To further investigate the molecular mechanisms associated with the loss of p62 in Tg mice, we assessed the mRNA and protein levels of several molecules, and found that the neighbor of the brca1 gene (NBr1), which is functionally and structurally similar to p62, is increased in Tg mice without p62 compared with control Tg mice. These findings suggest that p62 and NBR1 affect the pathogenesis of neurodegenerative diseases through the cooperative modulation of α-synuclein aggregation.

The sigma-1 receptor (SIGMAR1) is now known to be one of the endoplasmic reticulum (ER) chaperones, which participate in the degradation of misfolded proteins in cells via the ER-related degradation machinery linked to the ubiquitin-proteasome pathway. Mutations of the SIGMAR1 gene are implicated in the pathogenesis of familial frontotemporal lobar degeneration and motor neuron disease. Involvement of ER dysfunction in the formation of inclusion bodies in various neurodegenerative diseases has also become evident. We performed immunohistochemical staining to clarify the localization of SIGMAR1 in the brains of patients with neurodegenerative disorders, including trans-activation response DNA protein 43 (TDP-43) proteinopathy, tauopathy, α-synucleinopathy, polyglutamine disease and intranuclear inclusion body disease (INIBD). Double-immunocytofluorescence and Western blot analyses of cultured cells were also performed to investigate the role of SIGMAR1 using a specific exportin 1 inhibitor, leptomycin B and an ER stress inducer, thapsigargin. SIGMAR1 was consistently shown to be co-localized with neuronal nuclear inclusions in TDP-43 proteinopathy, five polyglutamine diseases and INIBD, as well as in intranuclear Marinesco bodies in aged normal controls. Cytoplasmic inclusions in neurons and glial cells were unreactive for SIGMAR1. In cultured cells, immunocytofluorescent study showed that leptomycin B and thapsigargin were shown to sequester SIGMAR1 within the nucleus, acting together with p62. This finding was also supported by immunoblot analysis. These results indicate that SIGMAR1 might shuttle between the nucleus and the cytoplasm. Neurodegenerative diseases characterized by neuronal nuclear inclusions might utilize the ER-related degradation machinery as a common pathway for the degradation of aberrant proteins.

Identification of the proteinaceous components of the pathological inclusions is an important step in understanding the associated disease mechanisms. We immunohistochemically examined two previously reported cases with eosinophilic neuronal cytoplasmic inclusions (NCIs)(case 1, Mori et al. Neuropathology 2010; 30: 648–53; case 2, Kojima et al. Acta Pathol Jpn 1990; 40: 785–91) using 67 antibodies against proteins related to cytoskeletal constituents, ubiquitin-proteasome system, autophagy-lysosome pathway and stress granule formation. Regional distribution pattern of eosinophilic NCIs in case 1 was substantially different from that in case 2. However, NCIs in both cases were immunonegative for ubiquitin and p62 and were immunopositive for stress granule markers as well as autophagy-related proteins, including valosin-containing protein. Considering that eukaryotic stress granules are cleared by autophagy and valosin-containing protein function, our findings suggest that eosinophilic NCIs in the present two cases may represent the process of autophagic clearance of stress granules.

FIG4 is a phosphatase that regulates intracellular vesicle trafficking along the endosomal-lysosomal pathway. Mutations of FIG4 lead to the development of Charcot-Marie-Tooth disease type 4J and amyotrophic lateral sclerosis (ALS). Moreover, ALS-associated proteins (transactivation response DNA protein 43 (TDP-43), fused in sarcoma (FUS), optineurin, ubiquilin-2, charged mutivesicular body protein 2b (CHMP2B) and valosin-containing protein) are involved in inclusion body formation in several neurodegenerative diseases. Using immunohistochemistry, we examined the brains and spinal cords of patients with various neurodegenerative diseases, including sporadic TDP-43 proteinopathy (ALS and frontotemporal lobar degeneration). TDP-43 proteinopathy demonstrated no FIG4 immunoreactivity in neuronal inclusions. However, FIG4 immunoreactivity was present in Pick bodies in Pick's disease, Lewy bodies in Parkinson's disease and dementia with Lewy bodies, neuronal nuclear inclusions in polyglutamine and intranuclear inclusion body diseases, and Marinesco and Hirano bodies in aged control subjects. These findings suggest that FIG4 is not incorporated in TDP-43 inclusions and that it may have a common role in the formation or degradation of neuronal cytoplasmic and nuclear inclusions in several neurodegenerative diseases.

Valosin-containing protein (VCP) is associated with multiple cellular functions, including ubiquitin-dependent protein degradation. Mutations in VCP are known to cause inclusion body myopathy with Paget's disease and frontotemporal dementia and familial amyotrophic lateral sclerosis (fALS; ALS14), both of which are characterized by trans-activation response DNA protein 43 (TDP-43)-positive neuronal cytoplasmic and nuclear inclusions. Recently, immunoreactivity for fALS-associated proteins (TDP-43, fused in sarcoma (FUS), optineurin and ubiquilin-2) were reported to be present in cytoplasmic and nuclear inclusions in various neurodegenerative diseases. However, the extent and frequency of VCP-immunoreactive structures in these neurodegenerative diseases are uncertain. We immunohistochemically examined the brains of 72 cases with neurodegenerative diseases and five control cases. VCP immunoreactivity was present in Lewy bodies in Parkinson's disease and dementia with Lewy bodies, and neuronal nuclear inclusions in five polyglutamine diseases and intranuclear inclusion body disease, as well as in Marinesco bodies in aged control subjects. However, other neuronal and glial cytoplasmic inclusions in tauopathies and TDP-43 proteinopathies were unstained. These findings suggest that VCP may have common mechanisms in the formation or degradation of cytoplasmic and nuclear inclusions of neurons, but not of glial cells, in several neurodegenerative conditions.

Amyotrophic lateral sclerosis (ALS) is characterized by motor neuron involvement with Bunina bodies (BBs) and transactivation response DNA protein 43 (TDP-43) inclusions. We examined the spinal cord (n = 20), hypoglossal nucleus (n = 6) and facial nucleus (n = 5) from ALS patients to elucidate the relationship between BBs and TDP-43 inclusions. BBs were found in the anterior horn in 16 of 20 cases, in the hypoglossal nucleus in all six cases and in the facial nucleus in four out of five cases. TDP-43 inclusions were found in each region of all the cases. Co-localization of BBs and TDP-43 inclusions was found in 15.2% of total neurons in the anterior horn, 29.2% in the hypoglossal nucleus and 17.3% in the facial nucleus. The frequency of TDP-43 inclusions was significantly higher in neurons with BBs than in those without in each region. Ultrastructurally, TDP-43-positive filamentous structures were intermingled with BBs. These findings suggest that there is a close relationship in the occurrence between BBs and TDP-43 inclusions.

Multiple system atrophy (MSA) is divided into two clinical subtypes: MSA with predominant parkinsonian features (MSA-P) and MSA with predominant cerebellar dysfunction (MSA-C). We report a 71-year-old Japanese man without clinical signs of MSA, in whom post mortem examination revealed only slight gliosis in the pontine base and widespread occurrence of glial cytoplasmic inclusions in the central nervous system, with the greatest abundance in the pontine base and cerebellar white matter. Neuronal cytoplasmic inclusions (NCIs) and neuronal nuclear inclusions (NNIs) were almost restricted to the pontine and inferior olivary nuclei. It was noteworthy that most NCIs were located in the perinuclear area, and the majority of NNIs were observed adjacent to the inner surface of the nuclear membrane. To our knowledge, only four autopsy cases of preclinical MSA have been reported previously, in which neuronal loss was almost entirely restricted to the substantia nigra and/or putamen. Therefore, the present autopsy case of preclinical MSA-C is considered to be the first of its kind to have been reported. The histopathological features observed in preclinical MSA may represent the early pattern of MSA pathology.

Aim Matrix metalloproteinase-3 (MMP-3), MMP-9 and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) play roles in remodeling and repairing tissue. The aim of the present study was to investigate correlations between plasma levels of these proteins and clinical severity of multiple system atrophy (MSA). Methods MMP-3, MMP-9 and TIMP-1 levels were measured by enzyme-linked immunosorbent assay (ELISA) in 72 MSA patients and 48 adult controls. Clinical severity was rated with the scale for assessing and rating ataxia (SARA) and the unified MSA rating scale (UMSARS). Immunohistochemistry and immunoblotting were used to assess MMP-3 expression in post-mortem brain tissue. Results Plasma MMP-3 was significantly lower in females than males, but MMP-9 and TIMP-1 showed no sex difference. Compared with age-matched controls (age ≥40 years), male MSA patients had significantly lower plasma MMP-3, but no difference was detected in female MSA patients versus controls. We observed significant correlations with rating scales in male, but not female, patients; plasma TIMP-1 positively correlated with SARA and UMSARS, whereas plasma MMP-3 showed an inverse correlation with the rating scales. These correlations became more evident when the MMP-3/TIMP-1 ratio was used as an index. Plasma MMP-9 did not correlate with any scales in male patients, but was positively correlated with UMSARS in female patients. Immunohistochemical studies of post-mortem brain tissues showed that total cerebellar MMP-3 expression was not significantly different between MSA patients and controls, but glial cytoplasmic inclusions were intensely immunoreactive for MMP-3. Conclusion MMP-3 and TIMP-1 are possible biomarker candidates for MSA. However, it is unclear whether they accurately reflect clinical progression.

Levodopa-induced dyskinesia has been suggested to result from maladaptive plasticity at corticostriatal synapses. Synaptic plasticity is based upon morphologic changes of dendritic spines. To elucidate whether the morphologic changes of spines occur in the striatum of rat models of levodopa-induced dyskinesia, we examined immunoreactivity of drebrin, an actin-binding protein localized in dendritic spines of excitatory synapses, using 6-hydroxydopamine-lesioned rats repeatedly treated with levodopa. The cross-sectional area of drebrin-immunoreactive organelles, putative spines, in the dopamine-denervated striatum of the levodopa-induced dyskinesia model was greater than that of the Parkinson's disease model. Immunoelectron microscopic examinations confirmed that drebrin-immunoreactive spines became enlarged in the dopamine-denervated striatum of the levodopa-induced dyskinesia model, but not in the Parkinson's disease model. These results suggest that the development of levodopa-induced dyskinesia is associated with enlargement of dendritic spines at corticostriatal excitatory synapses.

We describe an unusual case of myasthenia gravis. Our patient had been diagnosed as having myasthenia gravis with thymoma at the age of 64 years, and died of acute respiratory failure at the age of 80 years. Post mortem examination revealed CD8-positive lymphocytic infiltration with numerous giant cells in the skeletal muscles and myocardium. Immunohistochemical and ultrastructural studies revealed that there were two types of giant cells: histiocytic and myocytic in origin. Furthermore, both types of giant cells were immunopositive for proteins implicated in the late endosome and lysosome-protease systems, suggesting that endocytosis may be the key mechanism in the formation of giant cells. The present case, together with a few similar cases reported previously, may represent a particular subset of polymyositis, that is, giant cell polymyositis and myocarditis associated with myasthenia gravis and thymoma.

Ubiquitin-positive cytoplasmic inclusions are consistently found in various neurodegenerative diseases. As with ubiquitin, anti-p62/SQSTM1 (referred to as p62) antibody clearly immunostains these inclusions. p62 has a ubiquitin-associated domain at the carboxyl terminus and thereby interacts with ubiquitinated and misfolded proteins. Here we immunoprecipitated endogenous p62 in the cerebral cortex from patients with frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP) and found that p62 coimmunoprecipitated several proteins, including TDP-43, which is a major disease protein in FTLD-TDP. Unexpectedly, p62 immunoprecipitated a smaller amount of TDP-43 in FTLD-TDP compared with controls. Further analyses showed that p62 physiologically binds to TDP-43 and likely is involved in degradation of TDP-43 with 35-kDa, but not full-length TDP-43. Our results suggest that the interaction of TDP-43 and p62 is disrupted and may participate in the pathogenesis of TDP-43 proteinopathy.

F. Mori, K. Tanji, T. Kon, S. Odagiri, M. Hattori, Y. Hoshikawa, C. Kono, K. Yasui, S. Yokoi, Y. Hasegawa, M. Yoshida and K. Wakabayashi (2012) Neuropathology and Applied Neurobiology38, 322–328 FUS immunoreactivity of neuronal and glial intranuclear inclusions in intranuclear inclusion body disease Aims: Recent studies have shown that fused-in-sarcoma (FUS) protein is a component of ‘neuronal’ intranuclear inclusion bodies (INIBs) in the brains of patients with intranuclear inclusion body disease (INIBD). However, the extent and frequency of FUS-immunoreactive structures in INIBD are uncertain. Methods: We immunohistochemically examined the brain, spinal cord and peripheral ganglia from five patients with INIBD and five control subjects, using anti-FUS antibodies. Results: In controls, the nuclei of both neurones and glial cells were intensely immunolabelled with anti-FUS and neuronal cytoplasm was weakly positive for FUS. In INIBD, neuronal and glial INIBs in the brain and spinal cord were positive for FUS. FUS-positive INIBs were also found in the peripheral ganglia. The proportion of FUS-positive neuronal INIBs relative to the total number of inclusion-bearing neurones ranged from 55.6% to 83.3% (average 73.2%) and that of FUS-positive glial INIBs ranged from 45.9% to 85.7% (average 62.7%). The nucleus and cytoplasm of inclusion-bearing neurones and glial cells showed no FUS immunoreactivity. Conclusions: These findings suggest that FUS is incorporated into INIBs in both neurones and glial cells and that loss of normal FUS immunoreactivity may result from reduced protein expression and/or sequestration within inclusions.

Recent studies have shown that eosinophilic intranuclear inclusions (INI) in the brain of patients with intranuclear inclusion body disease (INIBD) are immunopositive for ubiquitin and ubiquitin-related proteins (URP). However, the extent and frequency of URP-immunoreactive inclusions in INIBD are uncertain. We immunohistochemically examined the brain, spinal cord and dorsal root ganglia from five patients with INIBD, using a virtual slide system with sequential staining of the same sections with hematoxylin and eosin and by immunolabeling with antibodies against ubiquitin and URP (NEDD8, NUB1, SUMO-1 and SUMO-2). Intranuclear inclusions were widely distributed in neurons and glial cells in all the cases. Sequential staining revealed that 100% of INI in neurons and glial cells were positive for ubiquitin. Moreover, the majority or a significant proportion of INI were positive for NEDD8, NUB1, SUMO-1 and SUMO-2. However, the proportions of NEDD8-, NUB1- and SUMO-1-positive inclusions were significantly higher in neurons than in glial cells (P < 0.05). These findings suggest that proteins related to ubiquitination and proteasomal degradation are involved in the formation of INI in INIBD.

Marinesco bodies (MBs) are spherical eosinophilic intranuclear inclusions in pigmented neurons in the substantia nigra and locus ceruleus. Previous immunohistochemical studies have shown that MBs are positive for ubiquitin, p62 and SUMO-1, suggesting the involvement of ubiquitination and related proteins in the formation or disaggregation of MBs. However, the involvement is not thoroughly understood. Therefore, we immunohistochemically examined the midbrain from five control subjects ranged from 53 to 84 years old. MBs were positive for various proteins implicated in the ubiquitin-proteasome system (ubiquitin, p62, EDD1, NEDD8, NUB1, SUMO-1 and SUMO-2), aggresome formation (HDAC6) and autophagy (ubiquitin, p62, LC3, GABARAP and GATE-16). These findings suggest that proteins related to ubiquitination, proteasomal degradation and autophagy are involved in the formation or disaggregation of MBs.

We report an autopsy case of arteriovenous malformation (AVM) of the right frontal lobe in a 50-year-old man, in whom post mortem examination revealed massive tau deposition in the affected cerebral cortex. The patient was diagnosed as having AVM at the age of 21 years, and died of unknown cause at the age of 50 years. Immunostaining with anti-phosphorylated tau antibody (AT8) revealed many NFTs and neuropil threads, but not glial tau accumulation, in the right frontal cortex surrounding the AVM. The NFTs and neuropil threads contained both 3-repeat and 4-repeat tau. Ultrastructurally, the NFTs consisted of paired helical filaments. In the other brain areas, a few NFTs were found in the parahippocampal gyrus. There was no amyloid deposition in the brain. A variety of disease conditions, including brain tumor, viral encephalitis, angioma and cervical spondylotic myelopathy, have been reported to show Alzheimer-type NFTs. The present findings indicate that abnormal tau deposition can occur in neurons, but not in glial cells, of the affected cerebral cortex surrounding AVM.

We report an incipient case of intranuclear inclusion body disease (INIBD) in a 78-year-old woman. No apparent neurological symptoms were noticed during the clinical course. Post mortem examination revealed widespread occurrence of eosinophilic intranuclear inclusions in neuronal and glial cells of the central and peripheral nervous systems, as well as in parenchymal cells of the visceral organs. The inclusions were observed more frequently in glial cells than in neuronal cells. Ultrastructurally, the inclusions consisted of granular and filamentous material. Immunohistochemically, the inclusions were positive for ubiquitin, ubiquitin-related proteins (NEDD8 ultimate buster 1, small ubiquitin modifier-1, small ubiquitin modifier-2 and p62), promyelocytic leukemia protein and abnormally expanded polyglutamine. Consistent with previous studies, the vast majority of inclusion-bearing glial cells were astrocytes. Furthermore, p25α-positive oligodendrocytes rarely contained intranuclear inclusions. These findings suggest that INIBD may occur in non-demented elderly individuals and that oligodendrocyte is also involved in the disease process of INIBD.

Histone deacetylase 6 (HDAC6) plays a crucial role in aggresome formation, resulting in the clearance of misfolded proteins. Previous studies have shown that HDAC6 is concentrated in Lewy bodies (LBs) in Parkinson's disease (PD) and dementia with LBs (DLB) (Cell 115: 727-738, 2003). We performed immunohistochemical and ultrastructural investigations on the brains of patients with various neurodegenerative disorders. Anti-HDAC6 antibody faintly immunostained the cytoplasm of neuronal and glial cells in control subjects. In PD and DLB, almost all of the cortical, brainstem-type and peripheral LBs were intensely immunolabeled with anti-HDAC6. In multiple system atrophy (MSA), the vast majority of glial cytoplasmic inclusions (GCIs) were also positive for HDAC6. Immunoelectron microscopy revealed that the reaction product was localized to the filamentous structures in LBs and GCIs. Various neuronal and glial inclusions in neurodegenerative disorders other than LB disease and MSA were HDAC6-negative. These findings suggest that accumulation of HDAC6 is specific to α-synucleinopathy and that both LBs and GCIs may represent cytoprotective responses to sequester toxic proteins.

TDP-43 is a major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with TDP-43 (FTLD-TDP). To evaluate the effectiveness of proteinase K (PK) treatment in antigen retrieval for native and phosphorylated TDP-43 protein, we examined the temporal cortex and spinal cord from patients with sporadic ALS and FTLD-TDP and control subjects. PK treatment following heat retrieval enhanced the immunoreactivity for native TDP-43 in controls as well as for native and phosphorylated TDP-43 in ALS and FTLD-TDP. A significant number of TDP-43-positive neuropil threads were demonstrated in lesions, in which routine immunohistochemistry revealed that the predominant inclusions are cytoplasmic. This retrieval method is the best of immunohistochemical techniques for demonstrating TDP-43 pathology, especially in the neuropil.

F. Mori, K. Tanji, Y. Miki, A. Kakita, H. Takahashi and K. Wakabayashi (2010) Neuropathology and Applied Neurobiology36, 345–352 Relationship between Bunina bodies and TDP-43 inclusions in spinal anterior horn in amyotrophic lateral sclerosis Aims: Amyotrophic lateral sclerosis (ALS) is characterized by upper and lower motor neurone involvement with Bunina bodies (BBs) and TDP-43 inclusions. To elucidate the relationship between BBs and TDP-43 inclusions, we examined the spinal cord from 18 patients with ALS. Methods: Five serial sections from lumbar cord were first stained with haematoxylin and eosin to detect BBs and subsequently immunostained with anti-TDP-43 antibody. Immunoelectron microscopy was performed on vibratome sections from two cases of ALS. Results: BBs were found in 15 out of 18 cases. TDP-43 inclusions were found in all the cases. The average incidence of anterior horn cells with BBs and TDP-43 inclusions relative to the total number of neurones was 17.1% and 46.4%, respectively. The concurrence of both inclusions in the same neurones was found in 15 cases. The incidence of co-localization of BBs and TDP-43 inclusions was 15.7% of total neurones. The frequency of TDP-43 inclusions was significantly higher in neurones with BBs than in those without. Ultrastructurally, TDP-43-immunoreactive filamentous structures were intermingled with early-stage BBs, but not associated with advanced-stage BBs. Conclusion: These findings suggest that there is a close relationship in the occurrence between BBs and TDP-43 inclusions.

We describe a 67-year-old woman without apparent neurological symptoms, in whom postmortem examination revealed widespread occurrence of eosinophilic neuronal cytoplasmic inclusions in the central and peripheral nervous systems. The inclusions were round, oval or rod-like in shape. Immunohistochemically, the inclusions were negative for ubiquitin and not labeled with any other antibodies, except for a partial and weak immunoreactivity with anti-neurofilament occurring rarely. Ultrastructurally, the inclusions revealed two different forms. The common form was entirely composed of bundles of wavy granule-coated filaments (20-30 nm in diameter). The other form consisted of a core containing linear filaments (12-15 nm in diameter) with electron-dense ribosome-like granules and an outer zone with wavy filaments as seen in the former. This inclusion seems to represent a new type of neuronal cytoplasmic inclusion.

The histological hallmark of Parkinson's disease (PD) is the presence of fibrillar aggregates called Lewy bodies (LBs). LB formation has been considered to be a marker for neuronal degeneration, because neuronal loss is found in the predilection sites for LBs. To date, more than 70 molecules have been identified in LBs, in which alpha-synuclein is a major constituent of LB fibrils. Alpha-synuclein immunohistochemistry reveals that diffuse cytoplasmic staining develops into pale bodies via compaction, and that LBs arise from the peripheral portion of pale bodies. This alpha-synuclein abnormality is found in 10% of pigmented neurons in the substantia nigra and more than 50% of those in the locus ceruleus in PD. Recent studies have suggested that oligomers and protofibrils of alpha-synuclein are cytotoxic, and that LBs may represent a cytoprotective mechanism in PD.

Decreased cardiac uptake of meta-iodobenzylguanidine (MIBG) on [(123)I] MIBG myocardial scintigraphy has been reported in the early stages of Parkinson's disease (PD), which suggests involvement of the cardiac sympathetic nerve in the early disease process of PD. For confirmation, we immunohistochemically examined cardiac tissue, sympathetic ganglia and medulla oblongata of 20 patients with incidental Lewy body disease (ILBD), which is thought to be a presymptomatic stage of PD, and 10 control subjects, using antibodies against tyrosine hydroxylase (TH) and neurofilament (NF). Immunoreactive nerve fibers of fascicles in the epicardium were well preserved in 10 of the 20 patients with ILBD and in the control subjects. In contrast, TH-immunoreactive nerve fibers had nearly disappeared in six subjects and were moderately decreased in four of the 20 patients with ILBD. Neuronal cell loss in the dorsal vagal nucleus and the sympathetic ganglia was not detectable in any of the ILBD patients examined. These findings suggest that degeneration of the cardiac sympathetic nerve begins in the early disease process of PD and that it occurs before neuronal cell loss in the dorsal vagal nucleus.

The patient was a 67-year-old female diagnosed with dilated cardiomyopathy. She had chronic atrial fibrillation (AF) with bradycardia and low left ventricular function (left ventricular ejection fraction (LVEF) 40%). She was admitted for congestive heart failure. She remained New York Heart Association (NYHA) functional class III due to AF bradycardia. Pacemaker implantation was necessary for treatment of heart failure and administration of dose intensive β-blockers. As she had normal His-Purkinje activation, we examined the optimal pacing sites. Hemodynamics of His-bundle pacing and biventricular pacing were compared. Pulmonary capillary wedge pressure (PCWP) was significantly lower on Hisbundle pacing than right ventricular (RV) apical pacing and biventricular pacing (13mmHg, 19mmHg, and 19mmHg, respectively) with an almost equal cardiac index. Based on the examination we implanted a permanent pacemaker for Direct His-bundle pacing (DHBP). After the DHBP implantation, the LVEF immediately improved from 40% to 55%, and BNP level decreased from 422 pg/ml to 42 pg/ml. The number of premature ventricular complex (PVC) was decreased, and non sustained ventricular tachycardia (NSVT) disappeared. Pacing threshold for His-bundle pacing has remained at the same level. His-bundle pacing has been maintained during 27 months and her long-term DHBP can improve cardiac function and the NYHA functional class.

We report a 70-year-old woman with sarcoidosis and multiple cranial nerve palsy. The patient suffered from dysarthria, dysphagia and weakness of the upper and lower extremities and died of sepsis. No abnormalities were noted in brain MRI. At autopsy, numerous epithelioid granulomas with Langhans giant cells were present in the bilateral lungs, including the hilar lymph nodes. The brain had a normal external appearance. Histologically, there were brainstem parenchymal lesions consisting of many microgranulomas, lymphocytic infiltration, activated microglias and astrocytosis. Perivascular lympocytic cuffing was also seen. Neither granulomas nor lymphocytic infiltration were seen in the leptomeninges. The present case was considered to be a peculiar type of neurosarcoidosis, that is, "sarcoid brainstem encephalitis".

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 Parkinson's 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 Alzheimer's 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.

The case reported here relates to a male infant with hydranencephaly who was born at 37 weeks of gestation and died immediately after birth. Post-mortem examination revealed that the cerebral hemispheres had been replaced by fluid-filled cavities within a normal-sized cranium. The membranous hemispheric wall was composed of gliosed tissue with multiple foci of necrosis and hemosiderin-laden macrophages. The ependyma was absent. Many necrotic foci containing hemosiderin were also found around the aqueduct and fourth ventricle. These findings suggest that hemorrhagic necrosis had occurred throughout the periventricular region, and more severely in the cerebral hemispheres. Moreover, numerous glioneuronal nests were found throughout the subarachnoid space and ventricles. Glioneuronal nests, if present, are usually minimal in hydranencephaly, whereas it is one of the pathological features of multicystic encephalopathy. The transition of multicystic encephalopathy to hydranencephaly has been demonstrated repeatedly. The former is a condition resulting from a severe circulatory disturbance, most often at the end of gestation or in the perinatal period. These lesions date later than hydranencephaly. Considering that numerous glioneuronal nests were found in the present case, it is likely that the encephaloclastic process developed toward the end of gestation.