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It has been reported that the development of TDP-43 pathology in cases of Lewy body disease (LBD) might be associated with the severity of tau pathology. However, the impact of α-synuclein pathology on TDP-43 accumulation in LBD remains unclear. To clarify whether α-synuclein pathology has an effect on TDP-43 accumulation, independent of tau pathology, we examined by immunohistochemistry 56 cases of LBD using a phosphorylation-dependent TDP-43 antibody. The frequency of TDP-43 pathology in all LBD cases was 18% (10/56). In 37 LBD cases with no or low tau burden (LBD-Ltau; Braak NFT stages 0-II), the frequency of TDP-43 pathology was 19% (7/37). The frequency of TDP-43 pathology in diffuse neocortical type LBD-Ltau cases was 36% (4/11), which was higher than those in limbic and brain stem-predominant types (11-14%). The amygdala and entorhinal cortex were the most frequently affected sites of TDP-43 pathology in LBD-Ltau cases. In LBD-Ltau cases, the proportion of diffuse neocortical type LBD was higher in the TDP-43-positive cases, than that in TDP-43-negative cases (57 vs. 23%). In all LBD cases, α-synuclein pathology in the temporal cortex was significantly more severe in TDP-43-positive cases, and significantly correlated with the severity of TDP-43 pathology in the amygdala. In a multivariate model, the presence of severe α-synuclein pathology was significantly associated with the development of TDP-43 pathology independent of age at death and tau pathology. In the amygdala, TDP-43 was often colocalized with α-synuclein or tau. Given these findings, we suggest that α-synuclein pathology is associated with TDP-43 accumulation in LBD cases.

TDP-43 is characteristically accumulated in TDP-43 proteinopathies such as frontotemporal lobar degeneration and motor neurone disease, but is also present in some tauopathies, including Alzheimer's disease, argyrophilic grain disease, and corticobasal degeneration (CBD). However, several studies have suggested that cases of progressive supranuclear palsy (PSP) lack TDP-43 pathology. We have therefore examined limbic regions of the brain in 19 PSP cases, as well as in 12 CBD cases, using phosphorylation-dependent anti-TDP-43 antibodies. We observed TDP-43-positive inclusions in five PSP cases (26%), as well as in two CBD cases (17%). The amygdala and hippocampal dentate gyrus were most frequently affected in PSP. Regional tau burden tended to be higher in TDP-43-positive PSP cases, and a significant correlation between tau and TDP-43 burden was noted in the occipitotemporal gyrus. Hippocampal sclerosis (HS) was found in 3/5 TDP-43-positive PSP cases, but HS was significantly more frequent in TDP-43-positive than TDP-43 negative PSP cases. Dementia was present in 13/19 (58%) of the PSP cases, in 4/5 TDP-43-positive cases, in all 3 TDP-43-positive cases with HS, in 1/2 TDP-43-positive cases without HS, and 7/14 cases lacking both. TDP-43 and tau were frequently colocalized in the amygdala, but not in the hippocampal dentate gyrus. Immunoblotting demonstrated the characteristic (for TDP-43 proteinopathies) 45 and 25 kDa bands and high molecular weight smear in the TDP-43-positive PSP case. These findings suggest that (1) although PSP is nominally a tauopathy, pathological TDP-43 can accumulate in the limbic system in some cases, and (2) TDP-43 pathology may be concurrent with HS.

Although frontotemporal lobar degeneration with ubiquitin/TDP-43-positive inclusions (FTLD-TDP) and Pick's disease are common pathological substrates in sporadic FTLD, clinical differentiation of these diseases is difficult. We performed a retrospective review of medical records and semiquantitative examination of neuronal loss of 20 sporadic FTLD-TDP and 19 Pick's disease cases. Semantic dementia as the first syndrome developed only in FTLD-TDP patients. Impaired speech output in the early stage was five times more frequent in Pick's disease than in FTLD-TDP. The total frequency of asymmetric motor disturbances (e.g., parkinsonism, pyramidal signs, and contracture) during the course was significantly more frequent in FTLD-TDP (78%) than in Pick's disease cases (14%). Asymmetric pyramidal signs were found in 7 of 13 FTLD-TDP cases with corticospinal tract degeneration similar to primary lateral sclerosis. Frontotemporal dementia as the first syndrome was noted in both FTLD-TDP (28%) and Pick's disease cases (64%); however, only FTLD-TDP cases subsequently developed asymmetric motor disturbances, and some of the cases further exhibited hemineglect. Concordant with these clinical findings, degeneration in the temporal cortex, caudate nucleus, putamen, globus pallidus, substantia nigra, and corticospinal tract was significantly more severe in FTLD-TDP, and degeneration in the frontal cortex tended to be more severe in Pick's disease. Given these findings, the initial impairment of semantic memory or comprehension and subsequent asymmetric motor disturbances in sporadic FTLD patients predict sporadic FTLD-TDP rather than Pick's disease, while initial behavioral symptoms or non-fluent aphasia without subsequent asymmetric motor disturbances predict Pick's disease rather than sporadic FTLD-TDP.

Recent biochemical studies demonstrated that astrocytic differentiation and growth regulation are impaired in neurofibromatosis type 1 (NF1). However, non-neoplastic morphological abnormalities of glial cells in the NF1 brain have been hardly explored. We describe here characteristic glial lesions in the basal ganglia in three NF1 cases (age at death in cases 1-3: 77, 6.5, and 11 years). Clusters of 3-10 dysplastic cells similar to reactive astrocytes were observed in the amygdala, caudate nucleus, putamen, thalamus in cases 1 and 2. Gigantic astrocyte-like glial cells were noted in case 2. Perineuronal glial satellitosis was observed in the amygdala in case 1. Many glial clusters were encountered in case 3 as well, but the round nuclei of the glial cells were more hyperchromatic and showed more remarkable variation in size than those in the other cases. Glial clusters in all cases were glial fibrillary acidic protein- and/or vimentin-positive, but synaptophysin-, myelin basic protein-, and olig2-negative. The glial lesions in cases 1 and 3 were excitatory amino acid transporters 1 (EAAT1)- and EAAT2-negative, and those in case 2 EAAT1- and EAAT2-weakly positive. Proliferation markers Ki-67, proliferation cell nuclear antigen, and cyclin D1 were not expressed in any lesion. Glial clusters in case 3 showed weak to intense immunoreactivity to nestin, a stem cell marker protein. The brains of 19 cases including 14 with various degenerative diseases and five normal brains used as controls lacked the glial lesions observed in NF1 cases. Given these findings, glial clusters and perineuronal glial satellitosis may be histopathological features of the NF1 brain and are probably associated with altered regulation of astrocyte growth in NF1.

While both neuronal intermediate filament inclusion disease (NIFID) and basophilic inclusion body disease (BIBD) show frontotemporal lobar degeneration and/or motor neuron disease, it remains unclear whether, and how, these diseases differ from each other. Here, we compared the clinicopathological characteristics of four BIBD and two NIFID cases. Atypical initial symptoms included weakness, dysarthria, and memory impairment in BIBD, and dysarthria in NIFID. Dementia developed more than 1 year after the onset in some BIBD and NIFID cases. Upper and lower motor neuron signs, parkinsonism, and parietal symptoms were noted in both diseases, and involuntary movements in BIBD. Pathologically, severe caudate atrophy was consistently found in both diseases. Cerebral atrophy was distributed in the convexity of the fronto-parietal region in NIFID cases. In both BIBD and NIFID, the frontotemporal cortex including the precentral gyrus, caudate nucleus, putamen, globus pallidus, thalamus, amygdala, hippocampus including the dentate gyrus, substantia nigra, and pyramidal tract were severely affected, whereas lower motor neuron degeneration was minimal. While alpha-internexin-positive inclusions without cores were found in both NIFID cases, one NIFID case also had alpha-internexin- and neurofilament-negative, but p62-positive, cytoplasmic spherical inclusions with eosinophilic p62-negative cores. These two types of inclusions frequently coexisted in the same neuron. In three BIBD cases, inclusions were tau-, alpha-synuclein-, alpha-internexin-, and neurofilament-negative, but occasionally p62-positive. These findings suggest that: (1) the clinical features and distribution of neuronal loss are similar in BIBD and NIFID, and (2) an unknown protein besides alpha-internexin and neurofilament may play a pivotal pathogenetic role in at least some NIFID cases.

We report a case of a right-handed 74-year-old man who showed semantic dementia with a disease duration of 19 years. He initially presented with excessive use of pronouns and semantic paraphasia at the age of 55 years. Impairment of object recognition developed 5 years after the onset. Face recognition impairment and stereotypic behaviors developed 11 years after onset, and pyramidal signs 2 years before death. Pathological examination disclosed circumscribed severe atrophy in not only the bilateral temporal tips but also in the left precentral gyrus and pars opercularis in a motor speech field. Pyramidal tract involvement and loss of Betz cells were also evident. On the other hand, neurons in the anterior horns and hypoglossal nuclei were spared in number, although astrocytes were mildly proliferated. Ubiquitin-positive lesions were observed in the hippocampus, and frontal and temporal cortices. Neither Bunina bodies nor Pick bodies were present. These features clinically fit the international diagnostic criteria of semantic dementia and, histopathologically, frontotemporal lobar degeneration with motor neuron disease (FTLD-MND). This case suggests that (1) the distribution of cortical lesions associated with language disturbance is not uniform in FTLD-MND. It may be that only some cases of FTLD with ubiquitin pathology develop semantic dementia despite the high incidence of language disturbance, and (2) the precentral gyrus can be severely affected in FTLD-MND. After reviewing previous cases of FTLD-MND with a clinical course of more than 10 years, we also noticed that (3) FTLD-MND cases with a long disease duration often show upper motor neuron-predominant involvement.

We report the case of a 54-year-old woman with mental retardation who developed frontotemporal dementia and amyotrophic lateral sclerosis (ALS) in the presenium. She presented with dementia at age 48, and motor neuron signs developed at age 53. She had no family history of dementia or ALS. Postmortem examination disclosed histopathological features of ALS, including pyramidal tract degeneration, mild loss of motor neurons, and many Bunina bodies immunoreactive for cystatin C, but not ubiquitin-positive inclusions. Unusual features of this case included severe neuronal loss in the substantia nigra and medial globus pallidus. The subthalamic nucleus, limbic system, and cerebral cortex were well preserved. In addition, neurofibrillary tangles (NFTs) were found in the frontal, temporal, insular, and cingulate cortices, nucleus basalis of Meynert, and locus coeruleus, and to a lesser degree, in the dentate nucleus, cerebellum, hippocampus, and amygdala. No ballooned neurons, tufted astrocytes, or astrocytic plaques were found. Tau immunostaining demonstrated many pretangles rather than NFTs and glial lesions resembling astrocytic plaques in the frontal and temporal cortices. This glial tau pathology predominantly developed in the middle to deep layers in the primary motor cortex, and was frequently associated with the walls of blood vessels. NFTs were immunolabeled with 3-repeat and 4-repeat specific antibodies against tau, respectively. Although the pathophysiological relationship between tau pathology and the selective involvement of motor neurons, substantia nigra, and globus pallidus was unclear, we considered that it might be more than coincidental.

Alcoholic cerebellar degeneration (ACD) is a pivotal neurological complication in alcoholics. However, although there are a few autopsy reports and some data on its frequency, it is considered very rare in Japan. The aims of this study were (1) to estimate the frequency of the disease in Japanese autopsy cases, and (2) to examine the clinicopathological features of symptomatic and asymptomatic cases of ACD. We reviewed the records of 1,509 Japanese autopsies obtained from three autopsy series in Japan, and selected all 55 cases (3.6%) with alcoholism. On neuropathological reexamination, ACD was confirmed in six male alcoholics [0.4% of all subjects; 10.9% of all alcoholics; mean age at death 59.3+/-13.4 years (+/- SD)], including three asymptomatic cases. These frequencies were much lower than some previous Western findings, but more common than that has been expected in Japan. The frequencies of memory impairment and ataxia in ACD cases were significantly higher than those in alcoholics without any alcohol-related pathologies. In ACD cases, loss of Purkinje cells, narrowing of the width of the molecular layer, and tissue rarefaction in the granular layer were observed in the anterior and superior portions of the vermis of the cerebellum. In adjacent regions, the Purkinje cell and molecular layers were more mildly affected. The distribution of severely affected regions was more restricted in the asymptomatic cases than in the symptomatic cases. This study confirmed the frequency of asymptomatic cerebellar degeneration in alcoholics, suggesting that early intervention in alcoholism in the subclinical phase is important to prevent the development of cerebellar symptoms.

Microtubule-associated protein tau is the major component of the filamentous neurofibrillary lesions of Alzheimer's disease (AD) and other tauopathies. Recently, it has been reported that tau isoforms lacking both N-terminal exon 2 and exon 3 do not form straight filament- or paired helical filament-like filaments in vitro, and that the N-terminal exons facilitate assembly of full-length tau. However, neuropathological and biological studies on the N-terminal region of tau protein in human tissue have been limited. We performed a biochemical study on the abnormally phosphorylated tau in brains affected by AD and corticobasal degeneration (CBD), and an immunohistochemical study on tau-positive structures in neurodegenerative diseases, to clarify whether tau with the exon 3 insert was present in abnormal tau-positive structures. On immunoblots of sarkosyl-insoluble tau, anti-exon 3 antibody (anti-E3 Ab) recognized two bands of 68 and 72 kDa in AD and only one band of 72 kDa in CBD. Immunohistochemically, anti-E3 Ab recognized most parts of the neurofibrillary tangles (NFT) in AD and Pick bodies in Pick's disease. In progressive supranuclear palsy (PSP) and CBD, most NFT and pretangles were positive for anti-E3 Ab, as were a small number of glial inclusions. These results indicate that abnormally phosphorylated tau containing the exon 3 insert is present in both PSP and CBD brain, and that CBD cannot be distinguished from PSP by immunoreactivity for anti-E3 Ab. Although most intraglial inclusions were negative for anti-E3 Ab, a few were positive. Therefore, tau isoforms containing the exon 3 insert are expressed at low levels in glial cells.

We report here a case of orthochromatic leukodystrophy with spheroids. A 40-year-old woman developed forgetfulness. About 1 year after the onset, clinical examination confirmed global intellectual deterioration with amnesia, spatiotemporal disorientation, and impairment of judgment. At age 43, she experienced tonic-clonic convulsions several times, and died of pneumonia at the age of 44. Alzheimer's disease was suspected clinically. Pathologically, there was severe diffuse demyelination of the deep white matter of the frontal, parietal and occipital lobes with relative preservation of the subcortical U fibers. In the central demyelinated areas, myelin loss was severe with diffuse gliosis, moderate loss of axons, and many axonal spheroids. At the periphery of the severely degenerated regions, there were a lot of macrophages and most had non-metachromatic lipid granules. The cerebral cortex was intact. The neuropathological findings of this case are consistent with hereditary diffuse leukoencephalopathy with spheroids (HDLS). Ten cases of HDLS were reviewed and presented many findings in common. The gray matter was intact and U fibers were well preserved in most cases. In white matter lesions, severe loss of myelin, moderate to severe axonal loss, much axonal swelling, and the presence of macrophages and hypertrophic astrocytes were common findings. In some cases with HDLS, dementia appeared without obvious neurological manifestations in the early stage. We should remember that some cases with HDLS show clinical symptoms similar to Alzheimer's disease, especially in the early stage.

The pathophysiological basis of cognitive dysfunction, including frontotemporal dementia (FTD), in patients with amyotrophic lateral sclerosis (ALS) and ALS with dementia (ALSD) remains unclear. On the other hand, increased expression of cyclooxygenase-2 (COX-2) in the spinal cord is thought to play a pivotal role in motor neuron degeneration in ALS. In this study, to assess the relationship between the neuronal COX-2 expression in the cerebrum, the formation of tau- and alpha-synuclein-negative but ubiquitin-positive neuronal inclusions (UPIs), and dementia in motor neuron disease (MND), we examined neuronal COX-2 immunoreactivity in the frontal cortex and hippocampus of patients with non-demented ALS without UPIs ( n=11), ALSD with UPIs ( n=6), and normal controls ( n=24) using a quantitative immunohistochemical technique. Neuronal COX-2 expression in all CA1-4 in the hippocampus was significantly up-regulated in the ALSD group, and, to lesser degree but significantly, in the ALS group. Neuronal COX-2 expression in the frontal cortex was also significantly up-regulated in the ALSD group but not in the ALS group. These findings suggest that (1) the frontal cortex and hippocampus of MND are involved in the same pathogenic process associated with COX-2 induction that has been observed in spinal anterior horn cells, (2) COX-2 induction in the cerebrum is a pathogenic process that can occur even in the absence of UPI formation in MND, and (3) COX-2 expression in the cerebrum may be associated with cognitive dysfunction in MND.

We describe three cases of early- (cases 1-3, 28-39 years) and one of late-onset (case 4, 76 years) Alzheimer's disease (AD) with 'cotton wool' plaques (CWPs) but without a family history indicating autosomal dominant inheritance. The early-onset cases, but not the late-onset case, showed remarkable aggression, disinhibition, and impulsiveness. Spastic paraparesis was observed in only one early-onset case. Hematoxylin-eosin-stained sections showed numerous CWPs, especially in the temporal cortex, in all cases. Bielschowsky-stained sections showed neurofibrillary tangles and minor neuritic changes surrounding the CWPs in three cases, but not in case 2. Gallyas-Braak-stained sections showed weak argyrophilia in homogeneous material of the CWPs in cases 2 and 4. Quantitative analysis demonstrated that Abeta42 was deposited more predominantly than Abeta40 in three cases. However, in case 2, approximately twice as much Abeta40 as Abeta42 was deposited. Tau immunostaining demonstrated neuritic changes in three cases, but not in case 2. alpha-Synuclein-positive Lewy bodies (LBs) and astrocytic lesions containing non-Abeta component of AD amyloid (NAC), a central fragment of alpha-synuclein, were found in case 3. In conclusion, (1) a frontal lobe syndrome-like personality change may be one of the characteristic clinical features of early-onset CWP-AD, (2) the deposition pattern of Abeta40 and Abeta42 in CWP-AD is more variable than that of presenilin-1-linked cases, (3) Abeta deposition can result in development of dementia without tau pathology, and (4) CWP-AD with LBs and several other neurodegenerative disorders with LBs share a common process involving alpha-synuclein and NAC deposition.

Fahr-type calcification is a relatively common finding in the elderly, and in younger patients with Alzheimer's disease, calcification in the basal ganglia is not uncommon. However, as far as we know, an immunohistochemical study of intracranial calcification in neurodegenerative diseases has not been performed. In this study, we examined intracranial calcification of the basal ganglia and cerebellum with antibodies against noncollagenous bone matrix proteins. Nineteen brains were employed. The diagnoses were diffuse neurofibrillary tangles with calcification in five, Alzheimer's disease in five, Pick's disease in one, progressive supranuclear palsy in one, Parkinson's disease in one, and six controls. By conventional histology, three patterns of calcium (Ca) deposition were recognized: diffuse deposition within the tunica media of small and medium-sized vessels (type 1 deposition), free spherical or lobulated concretions (type 2 deposition) in the parenchyma, and rows of small calcospherites lying along capillaries (type 3 deposition). Type 3 deposition is relatively rare, and may be a hallmark of severe intracranial calcification. Immunohistochemistry demonstrated that osteopontin was present diffusely in all Ca deposition types. Osteocalcin was present chiefly in the peripheral region of type 2 and 3 depositions, as well as in only the rims of type 1 deposition. Bone sialoprotein and osteonectin were found only in the core portions of type 2 and 3 depositions. In brief, type 1 deposition shows a different staining pattern from type 2 and 3. Different Ca deposition patterns of noncollagenous bone matrix proteins may suggest their separate roles in the pathogenesis of intracranial calcification.

Diffuse Lewy body disease (DLBD) is characterized by the presence of Lewy bodies (LB) in the neurons and neurites of cortical, subcortical, and brain stem structures. Recently, alpha-synuclein (alphaS) has been found to be a central constituent of LB. In DLBD, abnormal accumulation of alphaS has been reported in both neurons and glia, but studies on glial lesions in DLBD have been limited. We examined in detail the constituents and distribution of glial lesions in eight patients with DLBD and report the pathogenesis of the glial lesions. alphaS-positive neuronal cytoplasmic inclusions (NI), neuropil threads (NT), and coiled bodies (CB) showed similar immunostaining profiles. Without pretreatment, NI, NT, and CB were detected by all antibodies against alphaS. The immunostaining profile of star-like astrocytes (SLA) was quite different from those of NI, NT, and CB. A few SLA were stained by an antibody against the non-Abeta component portion of alphaS without pretreatment, but formic acid pretreatment dramatically enhanced SLA immunoreactivity. SLA and CB were found in all eight brains with DLBD. SLA were scarce in the brain stem, but there were hundreds of SLA per visual field at x100 magnification in the temporal cortex of most cases, while CB were found diffusely in both the cerebral cortex and brain stem, similar to NI. This suggests that the pathogenesis of SLA is different from those of NI and CB.

Approximately 60% of familial and sporadic Alzheimer's disease (AD) cases manifest Lewy bodies (LBs), of which a major component is alpha-synuclein. Although the pathogenic role of alpha-synuclein in AD remains unclear, LB formation might be associated with pathological beta-amyloid (Abeta) overproduction. Here, we present the clinical and pathological characteristics of two affected family members from a pedigree with the E184D mutation of presenilin-1. One case presented with typical clinical features of AD, but the other case also developed clinical characteristics of dementia with Lewy bodies (DLB), including visual hallucinations, delusions, and parkinsonism. In both cases, neuropathological examination revealed numerous neurofibrillary tangles and severe Abeta deposition in senile plaques and amyloid angiopathy, in which Abeta42 rather than Abeta40 was predominant. Furthermore, remarkable alpha-synuclein pathology, including LBs and the accumulation of the non-Abeta component of AD amyloid (NAC) in plaques and astrocytes, was detected only in the case that presented with the symptoms of DLB. These findings suggest that (1) LB pathology can influence the clinical features of familial AD, (2) the E184D mutation of presenilin-1 may be associated with the LB formation through Abeta overproduction, although the process of LB formation is strongly affected by other unknown mechanisms, (3) in neurodegenerative disorders with LBs, there is a common pathophysiological background inducing NAC accumulation in neuritic plaques and astrocytes, and (4) the NAC accumulation in neuritic plaques is modulated by the abnormally aggregated tau protein.

Diffuse neurofibrillary tangles with calcification (DNTC) is a rare tangle-predominant dementia, as well as one of the tauopathies lacking Abeta deposition. It is characterized by temporo-frontal lobar atrophy, Fahr-type calcification and, histopathologically, numerous neurofibrillary tangles in the limbic system and neocortex. Recently, accumulation of alpha-synuclein (alphaS), the precursor of the non-beta amyloid component (NAC) of Alzheimer's disease, has been shown in diverse neurodegenerative disorders, including Parkinson's disease, dementia with Lewy bodies, Alzheimer's disease, multiple system atrophy and parkinsonism-dementia complex of Guam. To clarify whether alphaS accumulates in other neurodegenerative disorders, we investigated eight DNTC brains using immunohistochemistry and demonstrated remarkable alphaS deposition in the neurons and astrocytes in many anatomical regions. Abundant Lewy bodies were observed in the amygdala (seven cases) and hippocampus (seven cases), and, to a lesser degree, in the substantia nigra (six cases) and dorsal vagal nucleus (five cases). In the hippocampus, many Lewy neurites were distributed in the stratum oriens and stratum pyramidale in the CA2-3 and the subiculum. Furthermore, numerous NAC-positive astrocytes were detected in the hippocampus and temporal cortex. This investigation reveals that neurons and astrocytes are extensively involved in remarkable alphaS pathology in the DNTC brain, and that the alphaS pathology compounds the cardinal pathological features of tau pathology. These findings suggest that (1) DNTC shares a common pathophysiological background with Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy in which abnormal alphaS aggregation is observed, and (2) there is an interaction between alphaS and tau pathology that does not involve amyloid in DNTC.

To evaluate glial lesions in cases of dementia with Lewy bodies (DLB), we studied the brains of four patients with DLB. Astrocytic star-like inclusions, which resembled tufted astrocytic fibrillary tangles in shape, were found in the cortex of two of these cases. In addition, coiled bodies were found in the white matter of the cerebrum in two cases. The astrocytic star-like inclusions were immunohistochemically negative for tau protein, ubiquitin and alpha-synuclein. The coiled bodies were immunohistochemically negative for tau protein but immunopositive for ubiquitin and alpha-synuclein. These results suggest that in DLB a primary degenerative process takes place in both glial cells and neurons.