Exploratory investigation on antibodies to GluN1 and cognitive dysfunction in patients with chronic autoimmune psychosis.

INTRODUCTION: Mild cognitive dysfunction has been implicated in a number of psychiatric diseases and affects social functioning. Although clinical criteria were recently proposed for autoimmune psychosis (AP), biomarkers have not yet been established for the severity and prognosis of cognitive dysfunction. We herein investigated the relationships between 3 types of serum antibodies and cognitive dysfunction in chronic psychiatric patients suspected of AP. METHODS: We included 31 patients suspected of AP and obtained information on their clinical characteristics. Three types of autoantibodies (the anti-N-methyl-D-aspartate receptor (anti-NMDAR Ab), anti-N-terminal of GluN1 (anti-GluN1-NT Ab), and anti-thyroid antibodies) were evaluated in serum. Cognitive function was assessed using Wechsler Adult Intelligence Scale-III. We examined the relationships between serum autoantibodies and cognitive dysfunction in patients using multiple regression models. RESULTS: Serum titers of anti-GluN1-NT Ab significantly contributed to the estimated score of working memory (B= -55.85, ß= -0.46, p= 0.01), while no correlation was observed between the other 2 types of antibodies and cognitive function. CONCLUSIONS: The present results indicate the potential of serum anti-GluN1-NT Ab as a biomarker for the severity and prognosis of cognitive dysfunction underlying various psychiatric symptoms in patients with AP. The pathological significance of anti-GluN1-NT Ab needs to be verified in future studies.

An exploratory investigation of antibodies to NMDA-type glutamate receptor subunits in serum and cerebrospinal fluid among psychiatric patients with anti-thyroid antibodies.

INTRODUCTION: Hashimoto's thyroiditis, which is characterized by anti-thyroid antibodies such as the anti-thyroglobulin (Tg) antibody and anti-thyroid peroxidase (TPO) antibody, is one of the autoimmune diseases associated with psychiatric illnesses. We previously reported a high prevalence of antibodies to N-terminals of N-methyl-D-aspartate (NMDA) type glutamate receptor (GluR) subunits (GluN1-NT and GluN2B-NT2) among psychiatric patients with anti-thyroid antibodies. However, it remains unclear whether the presence of anti-thyroid antibodies influences antibodies to GluN1-NT or GluN2B-NT2 among psychiatric patients. The present study aims to examine antibodies to GluN1-NT and GluN2B-NT2 in psychiatric patients with anti-thyroid antibodies (PPATs) and in those without (non-PPATs). MATERIAL AND METHODS: We recruited psychiatric inpatients aged 20-60 years. Patients were excluded if they had a history of neurological diseases, dementia, developmental disorders, tumors, or autoimmune diseases except autoimmune thyroiditis. The rest of the participants were divided into two groups according to the presence of serum anti-Tg and anti-TPO antibodies. We investigated serum and cerebrospinal fluid (CSF) antibodies to GluN1-NT and GluN2B-NT2 using an enzyme-linked immunosorbent assay (ELISA). RESULTS: We initially recruited seventy-three psychiatric inpatients. Forty-six patients were excluded because of the exclusion criteria. Eighteen PPATs and nine non-PPATs were ultimately enrolled. We also collected stored sera of eighteen healthy controls (HCs) who were age- and sex-matched with PPATs. The optical densities (ODs) of serum antibodies to GluN1-NT (p = 0.0020) and GluN2B-NT2 (p = 0.039) were significantly higher in PPATs than in HCs. The ODs of CSF antibodies to GluN1-NT (p = 0.030) and GluN2B-NT2 (p = 0.017) as well as the positive ratios of those antibodies were significantly higher in PPATs than in non-PPATs. CONCLUSION: Our finding indicates that detecting anti-thyroid antibodies in psychiatric patients would be a clue to consider psychiatric conditions related to antibodies to GluN1-NT/GluN2B-NT2. Further studies focusing on the relationship between PPATs and antibodies to GluN1-NT/GluN2B-NT2 are needed.

Influence of plasma matrix metalloproteinase levels on longitudinal changes in Alzheimer's disease (AD) biomarkers and cognitive function in patients with mild cognitive impairment due to AD registered in the Alzheimer's Disease Neuroimaging Initiative database.

OBJECTIVE: The present study investigated the effects of plasma matrix metalloproteinases (MMPs) on longitudinal changes in Alzheimer's disease (AD)-related biomarkers in cerebrospinal fluid (CSF), brain atrophy, and cognitive function in patients with mild cognitive impairment due to AD (MCI-AD). METHODS: We used data from the Alzheimer's Disease Neuroimaging Initiative database. We included 95 ApoE4-positive patients with MCI-AD who were confirmed to have low Aß42 and/or high phosphorylated-tau (p-tau) in CSF. We obtained baseline demographic data, plasma MMP levels, including MMP-1, -2, -7, -9, -10, and tissue inhibitor of MMP-1 (TIMP-1), longitudinal annual data on Aß42, total tau, and p-tau in CSF, MRI-measured hippocampal volumes, and cognitive function evaluated by the Mini-Mental State Examination (MMSE) and AD Assessment Scale-11 (ADAS-11) over 4 years. We examined the effects of baseline MMP levels on longitudinal changes in CSF AD biomarkers, hippocampal volumes, and cognitive function using a linear mixed regression analysis. RESULTS: No significant differences were observed in baseline plasma MMP levels between MCI-AD patients and control subjects, except for MMP-10, which was significantly lower in MCI-AD than in controls. The baseline levels of MMPs did not correlate with longitudinal changes in CSF biomarkers. Declines in hippocampal volumes and cognitive function evaluated by MMSE and ADAS-11 were significantly faster in MCI-AD patients with high-MMP-9 levels at baseline than in those with middle and low MMP-9 levels at baseline. CONCLUSION: High plasma MMP-9 levels in MCI-AD patients might enhance neurodegeneration and cognitive decline.

Regional cerebral glucose metabolism in systemic lupus erythematosus patients with major depressive disorder.

OBJECTIVES: Depression is frequently observed in patients with systemic lupus erythematosus (SLE). Neuropsychiatric SLE (NPSLE) patients often exhibit cerebral hypometabolism, but the association between cerebral metabolism and depression remains unclear. To elucidate the features of cerebral metabolism in SLE patients with depression, we performed brain 18F-fluoro-d-glucose positron emission tomography (FDG-PET) on SLE patients with and without major depressive disorder. METHODS: We performed brain FDG-PET on 20 SLE subjects (5 male, 15 female). The subjects were divided into two groups: subjects with major depressive disorder (DSLE) and subjects without major depressive disorder (non-DSLE). Cerebral glucose metabolism was analyzed using the three-dimensional stereotactic surface projection (3D-SSP) program. Regional metabolism was evaluated by stereotactic extraction estimation (SEE), in which the whole brain was divided into segments. RESULTS: Every SLE subject exhibited cerebral hypometabolism, in contrast to the normal healthy subjects. Regional analysis revealed a significantly lower ER in the left medial frontal gyrus (p=0.0055) and the right medial frontal gyrus (p=0.0022) in the DSLE group than in the non-DSLE group. CONCLUSION: Hypometabolism in the medial frontal gyrus may be related to major depressive disorder in SLE. Larger studies are needed to clarify this relationship.

Voxel-wise correlations between cognition and cerebral blood flow using arterial spin-labeled perfusion MRI in patients with Alzheimer's disease: a cross-sectional study.

BACKGROUND: To analyze voxel-wise correlation between cerebral blood flow (CBF) measured using ASL-MRI and cognition in patients with Alzheimer's disease (AD). METHODS: Forty-one patients diagnosed with AD or mild cognitive impairment due to AD were recruited for this study. CBF images were obtained using ASL-MRI (n = 41) with a post-labeling delay (PLD) of 1.5 and 2.5 s (PLD1.5 and PLD2.5, respectively) using a 3 T scanner, in addition to brain perfusion SPECT with N-isopropyl-4-[I-123]iodoamphetamine (n = 28). Voxel-based analyses were performed for ASL-MRI and SPECT using Mini-Mental State Examination (MMSE) scores as covariates. Differences in CBF between PLD1.5 and PLD2.5 were assessed using a paired t-test with SPM12. RESULTS: Significant positive correlations were observed between MMSE scores and CBF at PLD1.5 in the right posterior cingulate cortex (PCC), and both temporo-parietal association cortexes. At PLD2.5, significant positive correlations were determined for MMSE scores and CBF in the superior parietal lobule and the right temporo-parietal association cortex. SPECT showed significant positive correlations in the PCC and both temporo-parietal association cortexes (right-side dominant). PLD1.5 showed significantly higher CBF than PLD2.5 in the proximal areas of vascular territories of the anterior, middle, and posterior cerebral arteries. CONCLUSIONS: Significant positive correlations in CBF, measured with both ASL-MRI and SPECT, with cognition were found in the PCC and temporo-parietal association cortexes. PLD1.5 and PLD2.5 showed similar correlations with cognition, although the CBF images had significant differences.

Accumulated α-synuclein affects the progression of GM2 gangliosidoses.

The accumulation of α-synuclein (ASyn) has been observed in several lysosomal storage diseases (LSDs) but it remains unclear if ASyn accumulation contributes to LSD pathology. ASyn also accumulates in the neurons of Sandhoff disease (SD) patients and SD model mice (Hexb-/- ASyn+/+ mice). SD is a lysosomal storage disorder caused by the absence of a functional ß-subunit on the ß-hexosaminidase A and B enzymes, which leads to the accumulation of ganglioside in the central nervous system. Here, we explored the role of accumulated ASyn in the progression of Hexb-/- mice by creating a Hexb-/- ASyn-/- double-knockout mice. Our results show that Hexb-/- ASyn-/- mice demonstrated active microglia levels and less dopaminergic neuron loss, without altering the neuronal storage of ganglioside. The autophagy and ubiquitin proteasome pathways are defective in the neurons of Hexb-/- ASyn+/+ mice. In ultrastructural physiological studies, the mitochondria structures look degenerated and dysfunctional. As a result, expression of manganese superoxide dismutase 2 are reduced, and reactive oxygen species-mediated oxidative damage in the neurons of Hexb-/- ASyn+/+ mice. Interestingly, these dysfunctions improved in Hexb-/- ASyn-/- mice. But any clinical improvement were hardly observed in Hexb-/- ASyn-/- mice. Taken together, these findings suggest that ASyn accumulation plays an important role in the pathogenesis of neuropathy in SD and other LSDs, and is therefore a target for novel therapies.

Evaluation of titers of antibodies against peptides of subunits NR1 and NR2B of glutamate receptor by enzyme-linked immunosorbent assay in psychiatric patients with anti-thyroid antibodies.

BACKGROUND: Patients with anti-thyroid antibodies (ATAs) are reported to exhibit atypical psychiatric symptoms. We have been reported that psychiatric patients with ATAs (PPATs) have anti-N-methyl-Daspartate (NMDA) type glutamate receptor (NMDA-R) antibodies by western blot analysis. NMDA-R forms a tetramer with the subunit glutamate receptors (GluR) GluRζ1 (NR1) and GluRε2 (NR2B). However, the possible etiological role of anti-NR1 and anti-NR2B antibodies in PPATs remains unclear. METHODS: First, we evaluated titers of anti-NR1 and anti-NR2B antibodies in PPATs by enzyme-linked immunosorbent assay (ELISA). Next, we investigated the relationships among titers of anti-NR1 and anti-NR2B antibodies. Finally, we investigated the relationship between anti-NMDAR antibodies and the psychiatric symptoms in the PPATs. RESULTS: There was a strong correlation between anti-NR1 antibodies and anti-NR2B antibodies in the CSF, and some correlation between these antibodies in the serum. High titers of anti-NR2B antibodies in the serum of PPATs contributed to development of hallucinations and high titers of anti-NR1 antibodies in the serum contributed to development of anxiety by logistic regression. CONCLUSION: High titers of anti-NR2B antibodies in the serum is a risk factor for hallucinations and high titers of anti-NR1 antibodies in the serum is a risk factor for anxiety in PPATs.

Chorea as a clinical feature of the basophilic inclusion body disease subtype of fused-in-sarcoma-associated frontotemporal lobar degeneration.

Choreoathetoid involuntary movements are rarely reported in patients with frontotemporal lobar degeneration (FTLD), suggesting their exclusion as a supportive feature in clinical diagnostic criteria for FTLD. Here, we identified three cases of the behavioral variant of frontotemporal dementia (bvFTD) that display chorea with fused in sarcoma (FUS)-positive inclusions (FTLD-FUS) and the basophilic inclusion body disease (BIBD) subtype. We determined the behavioral and cognitive features in this group that were distinct from other FTLD-FUS cases. We also reviewed the clinical records of 72 FTLD cases, and clarified additional clinical features that are predictive of the BIBD pathology. Symptom onset in the three patients with chorea was at 44.0 years of age (±12.0 years), and occurred in the absence of a family history of dementia. The cases were consistent with a clinical form of FTD known as bvFTD, as well as reduced neurological muscle tone in addition to chorea. The three patients showed no or mild parkinsonism, which by contrast, increased substantially in the other FTLD cases until a later stage of disease. The three patients exhibited severe caudate atrophy, which has previously been reported as a histological feature distinguishing FTLD-FUS from FTLD-tau or FTLD-TAR DNA-binding protein 43. Thus, our findings suggest that the clinical feature of choreoathetosis in bvFTD might be associated with FTLD-FUS, and in particular, with the BIBD subtype.

A Case of Parkinson Disease With Both Visual Hallucination and Pain Improved by Gabapentin.

OBJECTIVES: Visual hallucinations (VHs) and pain are common non-motor symptoms in Parkinson disease (PD). Although dopaminergic dysfunction has traditionally been considered as the principal cause of these symptoms, the detail mechanisms are still unclear. Conventional treatment for VH, decrease of dopamine agonists, and use of antipsychotic medications often lead to an exacerbation of motor symptoms and excessive sedation. Gabapentin (GPT) is an antiepilepsy drug, which affects the glutamic acid neuron system and the γ-amino butyric acid neuron system. It is also known to have an analgesic effect. Here, we report a case of PD in which GPT improved both VH and pain without any adverse effects. METHODS: This study is a case report. RESULTS: The subject is an 81-year-old Japanese man who was diagnosed with PD at the age of 67 years. His Hoehn and Yahr staging scale was IV. He developed VH of insects and also experienced pain, which is, as he described, caused by these insects invading his body. Despite the general treatments, VH and pain persisted. Moreover, exacerbation of motor symptoms and excessive sedation hindered a further attempt. Gabapentin was administered to ease his pain. After that, not only pain but also VH disappeared without any adverse effects. CONCLUSIONS: The positive outcomes of GPT on VH and pain without any adverse effects may offer us a useful alternative treatment for PD. Further experience and study are needed to prove the efficacy of this agent.

[A Patient with Probable Dementia with Lewy Bodies and Positive Autoantibodies against the Anti-NH2-terminal of α-Enolase].

Dementia with Lewy bodies (DLB) is clinically characterized by progressive dementia that is frequently accompanied by neurological and psychiatric manifestations. Hashimoto's encephalopathy (HE) is a rare autoimmune disease with neurological and psychiatric manifestations that is not well understood. However, this disease has attracted growing attention as a treatable dementia. Although autoimmune mechanisms are thought to play a pathogenic role in HE, the etiology of the disease remains unclear. Recently, it was reported that the serum in patients with HE is frequency positive for autoantibodies against the anti-NH2-terminal of α-enolase (anti-NAE), indicating a useful serological diagnostic marker for HE. We report the case of an 81-year-old Japanese woman with probable DLB and hypothyroidism. In her serum, elevated anti-thyroid antibodies and positive autoantibodies against anti-NAE were observed. Elevated levels of anti-glutamate receptor ε2 subunit (GluRε2) antibodies were also detected in her cerebrospinal fluid. Because her clinical condition became stable after treatment with cholinesterase inhibitor, levodopa, and levothyroxine, immunotherapy was not performed. Although the relationship between autoimmunity and cognitive decline in this patient was unclear, the present observations suggest the coexistence of neurodegeneration and autoimmunity as the underlying pathogenic mechanism.

Neuropathological investigation of hypocretin expression in brains of dementia with Lewy bodies.

Hypocretin (Hcrt) is a neuropeptide synthesized in the lateral hypothalamus (LHT) that plays a key role in maintaining arousal state. In Parkinson's disease (PD), a narcolepsy-like syndrome is commonly seen, and a previous study showed substantial Hcrt neuronal loss in accordance with PD severity. In the present study, we quantitatively examined Hcrt immunoreactivity and α-synuclein and tau pathologies in the LHT and locus coeruleus (LC) in dementia with Lewy bodies (DLB) (n=15), Alzheimer's disease (AD) (n=14), and controls (n=7). In the LHT, substantial Hcrt-positive neurons were detected in controls. In contrast, in DLB and AD, the numbers of both total neurons and Hcrt-positive neurons were significantly reduced. The reduction of the latter was significantly severer in DLB than in AD. In the LC of controls, many Hcrt-positive axonal terminals were found. In contrast, the amount of Hcrt immunoreactivity was significantly reduced both in DLB and AD. In DLB, some Lewy body (LB)-bearing neurons were detected in the LHT, but the Hcrt-positive neurons did not have any LBs. Meanwhile, some tau-positive neurofibrillary tangle (NFT)-bearing neurons were detected in the LHT, and Hcrt-positive neurons occasionally contained NFTs. We observed a significant negative correlation between the number of Hcrt-positive neurons in the LHT and the neurofibrillary stage (r=-0.67, p=0.0067), whereas no significant correlation was found between the number of Hcrt-positive neurons and the Lewy stage (r=-0.47, p=0.077). This is the first report clarifying the substantial loss of Hcrt neurons in the LHT and of Hcrt axonal terminals in the LC in DLB and the correlation between the severity of Hcrt neuronal loss and progression of neurofibrillary pathology.

Autopsy case of concurrent Huntington's disease and neurofibromatosis type 1.

We report here an autopsy case of concurrent Huntington's disease (HD) and neurofibromatosis type 1 (NF1), also known as von Recklinghausen's disease. The patient was a Japanese woman with a significant hereditary burden: seven of her family members within four generations were affected by either NF1 or concurrent HD and NF1. She was diagnosed as having NF1 at age 24. At age 40, she showed signs of irritability, aggressive and childish behaviour, which became progressively worse. At age 48, rigidity and spastic gait were observed. One year later, choreoathetoid involuntary movements became apparent. Diagnosis of HD was made by identification of the abnormally expanded cytosine-adenine-guanine repeats in the Huntington's disease gene. Her condition deteriorated gradually to an apallic state and she died at age 60. Post-mortem examination revealed extensive brain atrophy, which was particularly severe in the frontal and temporal cortices and the striatum. The degree of neurodegenerative change seemed to correspond to grade IV. Polyglutamine positive inclusions were seen frequently in all layers of the cerebral cortex and in the amygdala and hippocampus. Inclusions were also present in the striatum, but there were fewer than in the cortex. Remarkably, neuronal intranuclear inclusions were present in the cerebellum, although they are usually not seen in HD. Features associated with the central nervous system involvement of NF1 were not found in the brain, but HD pathology might have been accelerated by the concurrence of NF1. This is the third report of a case with concurrent HD and NF1 in the world, and the first study in which occurrence of polyglutamine inclusions was confirmed on post-mortem examination.

Anti-glutamate receptor ɛ2 antibodies in psychiatric patients with anti-thyroid autoantibodies--a prevalence study in Japan.

Patients with anti-thyroid antibodies (ATAs) present various kinds of psychiatric conditions. When these psychiatric patients with ATAs (PPATs) show responsiveness to immunotherapy, they are frequently diagnosed with a diffuse progressive type of Hashimoto's encephalopathy (HE). Anti-glutamate receptor ɛ2 subunit (GluRɛ2) antibodies have previously been reported in HE patients. However, it is unclear whether there is any relationship between PPATs, including HE patients, and anti-GluRɛ2 antibodies. We investigated anti-GluRɛ2 antibodies in the serum and cerebrospinal fluid (CSF) of 15 PPATs, and we compared the results with those of 11 patients with neuropsychiatric systemic lupus erythematosus (NPSLE), an anti-glutamate receptor antibody-related disease. We then compared the neuropsychiatric symptoms between the PPATs with and without anti-GluRɛ2 antibodies. The prevalence of anti-GluRɛ2 antibodies was significantly higher in the CSF than in the serum of PPATs (41.7% versus 6.7%; p=0.040). The prevalence of anti-GluRɛ2 antibodies was slightly higher in the CSF of PPATs than NPSLE patients. PPAT-GluR(+)s showed a significantly higher prevalence of emotional instability (100% versus 33.3%; p=0.03) and also showed a significantly lower prevalence of delusions (0% versus 100%; p=0.001) and hallucinations (17% versus 83%; p=0.038) than PPAT-GluR(-)s. Our results suggest that anti-GluRɛ2 antibodies may be associated with the neuropsychiatric manifestation of PPATs.

Localization of fused in sarcoma (FUS) protein to the post-synaptic density in the brain.

Mutations in the fused in sarcoma (FUS) gene are linked to a form of familial amyotrophic lateral sclerosis (ALS), ALS6. The FUS protein is a major component of the ubiquitin-positive neuronal cytoplasmic inclusions in both ALS6 and some rare forms of frontotemporal lobar degeneration (FTLD). The latter are now collectively referred to as FTLD-FUS. In the present study, we investigated the localization of FUS in human and mouse brains. FUS was detected by western blot as an approximately 72 kDa protein in both human and mouse brains. Immunohistochemistry using lightly fixed tissue sections of human and mouse brains revealed FUS-positive granular staining in the neuropil, in addition to nuclear staining. Such granules are abundant in the gray matter of the brainstem and spinal cord. They are not frequent in the telencephalon. At the light microscopic level, FUS-positive granules are often co-localized with synaptophysin and present in association with microtubule-associated protein 2-positive dendrites. In the synaptosomal fraction of mouse brain, FUS is detected mainly in the post-synaptic density fraction. Thus, while FUS is primarily a nuclear protein, it may also play a role in dendrites. In the brains of patients with FTLD with TDP-43 deposition (FTLD-TDP), the number of FUS-positive granules in the cortex is increased compared with control cases. The increase in Alzheimer's disease (AD) is less remarkable but still significant. The dendritic localization of FUS and its increase in FTLD-TDP and AD may have some implication for the pathophysiology of neurodegenerative diseases.

Progressive nonfluent aphasia: a rare clinical subtype of FTLD-TDP in Japan.

Progressive nonfluent aphasia (PNFA) is a clinical subtype of frontotemporal lobar degeneration (FTLD). FTLD with tau accumulation (FTLD-tau) and FTLD with TDP-43 accumulation (FTLD-TDP) both cause PNFA. We reviewed clinical records of 29 FTLD-TDP cases in the brain archive of our institute and found only one case of PNFA. The patient was an 81-year-old male at death. There was no family history of dementia or aphasia. He presented with slow, labored and nonfluent speech at age 75. Behavioral abnormality and movement disorders were absent. MRI at age 76 demonstrated atrophy of the perisylvian regions, including the inferior frontal gyrus, insular gyrus and superior temporal gyrus. The atrophy was more severe in the left hemisphere than the right. On post mortem examinations, neuronal loss was evident in these regions as well as in the substantia nigra. There were abundant TDP-43-immunoreactive neuronal cytoplasmic inclusions and round or irregular-shaped structures in the affected cerebral cortices. A few dystrophic neurites and neuronal intranuclear inclusions were also seen. FTLD-TDP showing PNFA seems to be rare but does exist in Japan, similar to that in other countries.

Neuropathological investigation of the hypometabolic regions on positron emission tomography with [18F] fluorodeoxyglucose in patients with dementia with Lewy bodies.

We performed a quantitative neuropathological examination of the hypometabolic regions on FDG PET in dementia with Lewy bodies (DLB), Alzheimer's disease (AD) and control cases. When the DLB cases were divided into two groups according to concomitant AD pathology (ADP), neuronal loss in the temporo-parietal association area was milder in the DLB groups than in the AD group, although there were no differences between the two DLB groups. Tau and Aß immunoreactivities were observed in the AD group and the DLB group with ADP, but were rare in the DLB group without ADP. Tau and Aß immunoreactivities as well as numbers of neurofibrillary tangles (NFTs) and neuritic plaques (NPs) were more common in the AD group than in the DLB group with ADP. There was no difference in neuronal loss in the occipital area among the three groups. α-Synuclein immunoreactivity was observed in the DLB groups but not in the AD group. There were no differences in α-synuclein immunoreactivity and number of Lewy bodies (LBs) between the two DLB groups. These findings indicate that the neuropathological bases of the hypometabolic regions in the temporo-parietal association and occipital area in DLB may be AD pathology and Lewy pathology, respectively.