Involvement of autophagic protein DEF8 in Lewy bodies.

Dysregulation of autophagy, one of the major processes through which abnormal proteins are degraded, is a cardinal feature of synucleinopathies, including Lewy body diseases [Parkinson's disease (PD) and dementia with Lewy bodies (DLB)] and multiple system atrophy (MSA), which are characterized by the presence of abnormal α-synuclein in neurons and glial cells. Although several research groups have reported that Rubicon family proteins can regulate autophagosome-lysosome fusion or positioning, little is known about their involvement in synucleinopathies. In the present study, by studying patients with PD (N = 8), DLB (N = 13), and MSA (N = 5) and controls (N = 16), we explored the involvement of Rubicon family proteins [Rubicon, Pacer and differentially expressed in FDCP8 (DEF8)] in synucleinopathies. Immunohistochemical analysis showed that not only brainstem-type Lewy bodies but also cortical Lewy bodies were immunoreactive for DEF8 in Lewy body diseases, whereas Rubicon and Pacer were detectable in only a few brainstem-type Lewy bodies in PD. Glial cytoplasmic inclusions in patients with MSA were not immunoreactive for Rubicon, Pacer or DEF8. Immunoblotting showed significantly increased protein levels of DEF8 in the substantia nigra and putamen of patients with PD and the temporal cortex of patients with DLB. In addition, the smear band of DEF8 appeared in the insoluble fraction where that of phosphorylated α-synuclein was detected. These findings indicate the involvement of DEF8 in the formation of Lewy bodies. Quantitative and qualitative alterations in DEF8 may reflect the dysregulation of autophagy in Lewy body diseases.

Pathological substrate of memory impairment in multiple system atrophy.

AIMS: Synaptic dysfunction in Parkinson's disease is caused by propagation of pathogenic α-synuclein between neurons. Previously, in multiple system atrophy (MSA), pathologically characterised by ectopic deposition of abnormal α-synuclein predominantly in oligodendrocytes, we demonstrated that the occurrence of memory impairment was associated with the number of α-synuclein-positive neuronal cytoplasmic inclusions (NCIs) in the hippocampus. In the present study, we aimed to investigate how abnormal α-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 α-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. α-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 α-synuclein oligomers than those without. CONCLUSIONS: Our results provide new insights into the role of α-synuclein oligomers as a possible pathological cause of memory impairment in MSA.

Neuropathology of Multiple System Atrophy, a Glioneuronal Degenerative Disease.

Multiple system atrophy (MSA) is a fatal disease characterized pathologically by the widespread occurrence of aggregated α-synuclein in the oligodendrocytes referred to as glial cytoplasmic inclusions (GCIs). α-Synuclein aggregates are also found in the oligodendroglial nuclei and neuronal cytoplasm and nuclei. It is uncertain whether the primary source of α-synuclein in GCIs is originated from neurons or oligodendrocytes. Accumulating evidence suggests that there are two degenerative processes in this disease. One possibility is that numerous GCIs are associated with the impairment of oligo-myelin-axon-neuron complex, and the other is that neuronal inclusion pathology is also a primary event from the early stage. Both oligodendrocytes and neurons may be primarily affected in MSA, and the damage of one cell type contributes to the degeneration of the other. Vesicle-mediated transport plays a key role in the nuclear translocation of α-synuclein as well as in the formation of glial and neuronal α-synuclein inclusions. Recent studies have shown that impairment of autophagy can occur along with or as a result of α-synuclein accumulation in the brain of MSA and Lewy body disease. Activated autophagy may be implicated in the therapeutic approach for α-synucleinopathies.

The clinical and neuropathological picture of adult neuronal intranuclear inclusion disease with no radiological abnormality.

In typical adult neuronal intranuclear inclusion disease (NIID) with predilection for the basal ganglia or cerebral cortex, not only neurons but also glial cells harbor intranuclear inclusions. In addition, these inclusions are present in the peripheral autonomic nervous system, visceral organs and skin. In NIID cases with an expansion of GGC repeats in the 5'-untranslated region (5'-UTR) of the Notch 2 N-terminal like C (NOTCH2NLC) gene, these repeats are located in an upstream open reading frame (uN2C) and result in the production of a polyglycine-containing protein called uN2CpolyG. Typically, patients with adult NIID show high-intensity signals at the corticomedullary junction on diffusion-weighted brain magnetic resonance imaging. We report a case of adult NIID in a 78-year-old Japanese male, who suffered from mild, non-progressive tremor during life but showed no radiographic abnormalities suggestive of adult NIID. Pathologically, ubiquitin-, p62- and uN2CpolyG-positive neuronal intranuclear inclusions were particularly frequent in the hippocampal formation, but were also seen in the enteric plexuses, kidney and cardiac muscles. By contrast, glial intranuclear inclusions were barely evident in the affected regions. The present case also had an immunohistochemical profile differing from that of typical adult NIID. The findings in this case suggest that adult NIID can show clinical, radiographic and pathological heterogeneity.

An autopsy case of amyotrophic lateral sclerosis with striatonigral and pallidoluysian degeneration and cat's-eye-shaped neuronal nuclear inclusions.

We report the case of a Japanese woman with sporadic amyotrophic lateral sclerosis (ALS) of 28 months' duration who died at the age of 66 years. Postmortem examination revealed moderate loss of neurons and phosphorylated TDP-43 (p-TDP-43)-immunoreactive neuronal and glial cytoplasmic inclusions in the upper and lower motor neurons. Additionally, marked neuronal loss was observed in the neostriatum, globus pallidum, subthalamic nucleus, and substantia nigra. p-TDP-43-immunoreactive inclusions were frequently found in these areas. Neuronal loss and TDP-43 pathology in the motor, striatonigral, and pallidoluysian systems were predominant on the right side. Moreover, p-TDP-43-immunoreactive cat's-eye-shaped neuronal nuclear inclusions (NNIs) were observed in the affected lesions. NNIs in the striatonigral system were also positive for valosin-containing protein (VCP). We diagnosed the patient as having ALS with striatonigral and pallidoluysian degeneration. Patients with ALS rarely experience pallido-nigro-luysian degeneration. To our best knowledge, only one case of ALS combined with striatonigral and pallidoluysian degeneration has been reported. Neuronal loss in the striatonigral and/or pallidoluysian systems has also been reported in patients with ALS with multisystem degeneration accompanied by long-term use of an artificial respirator. Based on these findings, a possibility of an extremely rare subtype of ALS demonstrating selective loss of neurons in the striatonigral and pallidoluysian systems exists; another possibility is that this type could be an early stage or forme fruste of ALS with multisystem degeneration. Although VCP-positive cat's-eye-shaped NNIs have been reported in spinocerebellar ataxia type-2 cases, our case report presents VCP-positive NNIs in a patient with ALS for the first time.

Novel tankyrase inhibitors suppress TDP-43 aggregate formation.

Transactive response DNA-binding protein of 43 kDa (TDP-43) abnormally forms aggregates in certain subtypes of frontotemporal lobar degeneration (FTLD) and in amyotrophic lateral sclerosis (ALS). The pathological forms of TDP-43 have reported to be associated with poly(ADP-ribose) (PAR), which regulates the properties of these aggregates. A recent study has indicated that tankyrase, a member of the PAR polymerase (PARP) family, regulates pathological TDP-43 formation under conditions of stress, and tankyrase inhibitors suppress TDP-43 aggregate formation and cytotoxicity. Since we reported the development of tankyrase inhibitors that are more specific than conventional inhibitors, in this study, we examined their effects on the formation of TDP-43 aggregates in cultured cells. Time-lapse imaging showed that TDP-43 aggregates appeared in the nucleus within 30 min of treatment with sodium arsenite. Several tankyrase inhibitors suppressed the formation of aggregates and decreased the levels of the tankyrase protein. Immunohistochemical studies demonstrated that tankyrase was localized to neuronal cytoplasmic inclusions in the spinal cords of patients with ALS. Moreover, the tankyrase protein levels were significantly higher in the brains of patients with FTLD than in the brains of control subjects. These findings suggest that the inhibition of tankyrase activity protects against TDP-43 toxicity. Tankyrase inhibitors may be a potential treatment to suppress the progression of TDP-43 proteinopathies.

GABA storage and release in the medial globus pallidus in L-DOPA-induced dyskinesia priming.

Levo-dihydroxyphenylalanine (L-DOPA) is the most effective treatment for Parkinson's disease; however, most patients develop uncontrollable abnormal involuntary movements known as L-DOPA-induced dyskinesia. L-DOPA-induced dyskinesia can be reduced by pallidotomy of the medial globus pallidus or pallidal deep brain stimulation, suggesting that the medial globus pallidus plays a significant role in the development of L-DOPA-induced dyskinesia. In the present study, the pathological changes of the medial globus pallidus in L-DOPA-induced dyskinesia were studied in rat models of Parkinson's disease (unilateral 6-hydroxydopamine lesioning) and L-DOPA-induced dyskinesia (L-DOPA injection in Parkinson's disease-model rats twice daily for 2 weeks, confirmed by display of dyskinesia-like abnormal involuntary movements). L-DOPA-induced dyskinesia-model rats displayed medial globus pallidus hypertrophy, enlarged axon terminals surrounding the dendrites of medial globus pallidus neurons, and increased density of synaptic vesicles in enlarged axon terminals on the lesioned side. Synaptic terminal enlargement reversed after discontinuation of L-DOPA. Histological studies revealed the enlarged synaptic terminals were those of GABAergic striatal (direct pathway) neurons. A single injection of L-DOPA enhanced GABA release in the medial globus pallidus on the lesioned side in L-DOPA-induced dyskinesia-model rats compared to Parkinson's disease-model rats. In addition, microinjection of muscimol, a GABAA receptor agonist, into the medial globus pallidus on the lesioned side of Parkinson's disease-model rats induced dyskinesia-like abnormal involuntary movements. Microinjection of bicuculline, a GABAA receptor antagonist, into the medial globus pallidus on the lesioned side alleviated L-DOPA-induced dyskinesia in Parkinson's disease-model rats that had received L-DOPA prior to the microinjection. These results indicate that priming for L-DOPA-induced dyskinesia comprises excessive GABA storage in axon terminals of the direct pathway and that expression of L-DOPA-induced dyskinesia is associated with enhanced GABA release into the medial globus pallidus after L-DOPA dosing and the resultant excessive stimulation of GABAA receptors.

Semi-urgent pulmonary vein isolation using cryoballoon for haemodynamically unstable atrial fibrillation storm in a patient with low cardiac output syndrome: a case report.

BACKGROUND: Atrial fibrillation and heart failure are common coexisting conditions requiring hospitalisation for heart failure and death. Pulmonary vein isolation is a well-established option for symptomatic atrial fibrillation and for atrial fibrillation concomitant with heart failure with reduced left ventricular ejection fraction. Recently, pulmonary vein isolation using cryoballoon showed non-inferiority to radiofrequency ablation with respect to the treatment of patients with drug-refractory paroxysmal atrial fibrillation. However, the effectiveness of acute-phase rhythm control by semi-urgent pulmonary vein isolation using cryoballoon in patients with haemodynamically unstable atrial fibrillation storm accompanied with low cardiac output syndrome is unclear. Herein, we present a case in which semi-urgent pulmonary vein isolation using cryoballoon was effective for acute-phase rhythm control against drug-resistant and haemodynamically unstable repetitive atrial fibrillation tachycardia accompanied with low cardiac output syndrome. CASE PRESENTATION: A 57-year-old man was hospitalised for New York Heart Association functional class 4 heart failure with atrial fibrillation tachycardia and reduced left ventricular ejection fraction of 20% accompanied with low cardiac output syndrome-induced liver damage. The haemodynamics collapsed during atrial fibrillation tachycardia, which had become resistant to intravenous amiodarone and repeated electrical cardioversions. In addition to atrial fibrillation, atrial tachycardia and common-type atrial flutter appeared on day 3. Multiple organ failure progressed gradually due to haemodynamically unstable atrial fibrillation tachycardia storm accompanied with low cardiac output syndrome. On day 4, to focus on treatment of heart failure and multiple organ failure, semi-urgent rescue pulmonary vein isolation using cryoballoon to atrial fibrillation and cavotricuspid isthmus ablation to common-type atrial flutter were performed for acute-phase rhythm control. Soon after the ablation procedure, atrial fibrillation and common-type atrial flutter were lessened, and sinus rhythm was restored. A stable haemodynamics was successfully achieved with the improvement of hepatorenal function. The patient was discharged on day 77 without complications. CONCLUSIONS: This case demonstrates that acute-phase rhythm control by semi-urgent pulmonary vein isolation using cryoballoon could be a treatment option in patients with haemodynamically unstable atrial fibrillation tachycardia storm accompanied with low cardiac output syndrome, which is refractory to cardioversion and drug therapy.

A mouse model of adult-onset multiple system atrophy.

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder clinically characterized by autonomic failure in addition to various combinations of symptoms of parkinsonism, cerebellar ataxia, and pyramidal dysfunction. Despite extensive research, the mechanisms underlying the progression of MSA remain unknown. Animal models of human diseases that recapitulate their clinical, biochemical and pathological features are indispensable for increasing our understanding of their underlying molecular mechanisms, which allows preclinical studies to be advanced. Because the onset of MSA occurs in middle age, an animal model that first manifests abnormal protein aggregates in adulthood would be most appropriate. We therefore used the Cre-loxP system to express inducible α-synuclein (Syn), a major component of the pathological hallmark of MSA, to generate a mouse model of MSA. Beginning in adulthood, these MSA model mice express excessive levels of Syn in oligodendrocytes, resulting in abnormal Syn accumulation and modifications similar to those observed in human MSA pathology. Additionally, MSA model mice exhibit some clinical features of MSA, including decreased motor activity. These findings suggest that this new mouse model of MSA represents a useful tool for analyzing the pathophysiological alterations that underlie the progression of this disease.

Trehalose intake and exercise upregulate a glucose transporter, GLUT8, in the brain.

Physical exercise influences cognitive function through a cascade of cellular processes that promote angiogenesis and neurogenesis. Autophagy is a cellular degradation system that is capable of producing energy in response to various conditions such as starvation, physical exercise and several treatments. Our previous report demonstrated that a disaccharide, trehalose, induced autophagy in the brain and reduced the levels of potentially toxic proteins. To achieve more efficient induction of autophagy in the brain, in this study, we examined the effect of disaccharide intake combined with exercise on autophagy in vivo. Consistent with the results of previous studies, our biochemical analyses demonstrated that trehalose increased the level of lipidated LC3 (LC3II) in the brain and liver of adult mice. However, contrary to our expectation, treadmill exercise reduced the level of LC3II in the brain and liver. Interestingly, glycogen storage was preserved in the liver of trehalose-intake mice even after exercise. Moreover, the trehalose transporter GLUT8 was increased in the liver by trehalose or in the brain by trehalose together with exercise. In contrast, the level of GLUT4 remained stable in the liver and brain even after exercise. These findings suggest that trehalose and GLUT8 coordinately contribute to energy supply in the brain.

Safety and Efficacy of Low-Dose Prasugrel as Part of Triple Therapy With Aspirin and Oral Anticoagulants in Patients With Atrial Fibrillation Undergoing Percutaneous Coronary Intervention　- From the TWMU-AF PCI Registry.

BACKGROUND: Using the standard maintenance dose of prasugrel (10 mg/day) as part of triple therapy with aspirin and an oral anticoagulant (OAC) is not recommended in the current guidelines because it increases the risk of bleeding compared with clopidogrel. However, the safety and efficacy of low-dose prasugrel (3.75 mg/day) as part of triple therapy has not been reported. Methods and Results: We registered 816 consecutive patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) from January 2011 to June 2016 at 8 hospitals in Japan. We examined the clinical outcomes of patients who received either low-dose prasugrel (n=57) or clopidogrel (n=451) as part of triple therapy after PCI. The incidences of bleeding (TIMI major and minor) and major adverse cerebrocardiovascular events (MACCE; all-cause death, nonfatal myocardial infarction, stent thrombosis, unplanned revascularization, and stroke) were evaluated. The cumulative 1-year incidence of bleeding was not significantly different (prasugrel 5.6% vs. clopidogrel 8.1%, log-rank P=0.55). In addition, the cumulative 1-year incidence of MACCE was also not significantly different (prasugrel 11.5% vs. clopidogrel 12.3%, log-rank P=0.88). CONCLUSIONS: Low-dose prasugrel, as part of triple therapy, did not increase the risk of bleeding compared with clopidogrel. Therefore, it can be an alternative to clopidogrel for patients with AF undergoing PCI.

An autopsy case of early-stage amyotrophic lateral sclerosis with TDP-43 immunoreactive neuronal, but not glial, inclusions.

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.

Immunoreactivity of myelin-associated oligodendrocytic basic protein in Lewy bodies.

Myelin-associated oligodendrocytic basic protein (MOBP) plays a role in structural maintenance of the myelin sheath in the central nervous system. Recent genome analyses have revealed that mutation in MOBP is a risk factor for various neurodegenerative diseases, including Alzheimer's disease (AD), tauopathies and transactivation response DNA-binding protein 43 kDa proteinopathies. Proteomics analysis has shown that MOBP is a component of cortical Lewy bodies (LBs). However, the immunohistochemical localization of MOBP in the human brain is not known. Using immunohistochemistry, we examined the brain, spinal cord and peripheral ganglia from patients with various neurodegenerative diseases and control subjects. In normal controls, MOBP immunoreactivity was evident in the myelin in the central and peripheral nervous systems (PNS), and neuronal cytoplasm in both the central and PNS. In Parkinson's disease and dementia with LBs, MOBP immunoreactivity was found in the core of LBs in the brainstem, cingulate cortex and sympathetic ganglia. No MOBP immunoreactivity was found in a variety of other neuronal or glial inclusions in other disorders, including multiple system atrophy, AD, Pick's disease, progressive supranuclear palsy, corticobasal degeneration, argyrophilic grain disease, amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Considering that up-regulation of MOBP has been reported in neurotoxic conditions, accumulation of MOBP in LBs may imply a cytoprotective mechanism in LB disease.

Atypical globular glial tauopathy with a combination of types I and II pathology.

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.

YOD1 attenuates neurogenic proteotoxicity through its deubiquitinating activity.

Ubiquitination, a fundamental post-translational modification of intracellular proteins, is enzymatically reversed by deubiquitinase enzymes (deubiquitinases). >90 deubiquitinases have been identified. One of these enzymes, YOD1, possesses deubiquitinase activity and is similar to ovarian tumor domain-containing protein 1, which is associated with regulation of the endoplasmic reticulum (ER)-associated degradation pathway. Indeed, YOD1 is reported to be involved in the ER stress response induced by mislocalization of unfolded proteins in mammalian cells. However, it has remained unclear whether YOD1 is associated with pathophysiological conditions such as mitochondrial damage, impaired proteostasis, and neurodegeneration. We demonstrated that YOD1 possesses deubiquitinating activity and exhibits preference for K48- and K63-linked ubiquitin. Furthermore, YOD1 expression levels increased as a result of various stress conditions. We demonstrated that the neurogenic proteins that cause Huntington disease and Parkinson's disease induced upregulation of YOD1 level. We observed that YOD1 reduced disease cytotoxicity through efficient degradation of mutant proteins, whereas this activity was abolished by catalytically inactive YOD1. Additionally, YOD1 localized to Lewy bodies in Parkinson's disease patients. Collectively, these data suggest that the deubiquitinase YOD1 contributes to pathogenesis of neurodegenerative disease by decreasing ubiquitination of abnormal proteins and their subsequent degradation.

Colocalization of Bunina bodies and TDP-43 inclusions in a case of sporadic amyotrophic lateral sclerosis with Lewy body-like hyaline inclusions.

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.

Alteration of mitochondrial protein PDHA1 in Lewy body disease and PARK14.

The histopathological hallmark of Parkinson's disease (PD) and dementia with Lewy bodies (DLB) is the occurrence of insoluble fibrillary aggregates known as Lewy bodies. Mitochondria play a vital role in energy production, and the pathogenesis of PD is associated with altered cellular metabolism due to mitochondrial dysfunction. The pyruvate dehydrogenase (PDH) complex provides a primary step in aerobic glucose metabolism by catalyzing the oxidative decarboxylation of pyruvate to acetyl CoA. Pyruvate dehydrogenase alpha 1 (PDHA1) forms the core structure of the PDH complex. Dysfunction of the PDH complex leads to energy production failure, resulting in various neurological disorders. However, no study has investigated the involvement of PDHA1 in the pathogenesis of PD. In the present study, we performed immunohistochemistry and immunoblotting to clarify the involvement of PDHA1 in idiopathic PD, DLB, PARK14-linked parkinsonism (PARK14; a familial form of PD), and multiple system atrophy, in comparison with normal controls. Here we report PDHA1 as a new component of brainstem-type Lewy bodies in idiopathic PD, DLB and PARK14, the level of PDHA1 protein being significantly decreased in the putamen and substantia nigra of patients with idiopathic PD. Our findings suggest that alteration of glucose metabolism through dysfunction of the PDH complex might occur in the pathogenesis of Lewy body disease and PARK14.

Multiple focal and macroreentrant left atrial tachycardias originating from a spontaneous scar at the contiguous aorta-left atrium area in a patient with hypertrophic cardiomyopathy: a case report.

BACKGROUND: Spontaneous scar-related left atrial tachycardia (AT) is a rare arrhythmia. We describe a patient with hypertrophic cardiomyopathy (HCM) who developed multiple, both focal and macroreentrant left ATs associated with a spontaneous scar located at the aorta-left atrium (LA) contiguous area. CASE PRESENTATION: A 65-year-old man with HCM complained of palpitations. Twelve-lead electrocardiogram showed narrow QRS tachycardia with 2:1 atrioventricular conduction. Two sessions of radiofrequency ablation (RFA) were required to eliminate all left ATs. In the first session, 3-dimensional electroanatomical mapping fused with the image constructed by multi-detector computed tomography showed a clockwise macroreentrant AT (AT1) associated with a low-voltage or dense scar area located along the aorta-LA contiguous area. AT1 was eliminated by RFA to the narrow isthmus with slow conduction velocity within the scar. Additional ATs (AT2-AT4) occurred 1 month after the first ablation. In the second session, AT2 and AT3 were identified as focal ATs with centrifugal propagation and few accompanying fragmentations, and AT4 as a macroreentrant AT with features similar to AT1. AT2 and AT3 were successfully eliminated by performing RFA to the earliest activation site, and AT4 was terminated by performing RFA to the narrow isthmus with slow conduction velocity. No ATs have recurred for 11 months after these RFAs. Interestingly, the substrate for all left ATs was associated with the aorta-LA contiguous area. CONCLUSION: To our knowledge, this is the first case of multiple, both focal and macroreentrant left ATs associated with a contiguous aorta-LA spontaneous scar area in a patient with HCM.

The role of NUB1 in α-synuclein degradation in Lewy body disease model mice.

Abnormal α-synuclein is deposited in neuronal cytoplasmic inclusions and presynapses in Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Previously we have shown that NUB1 is accumulated in these specific regions together with abnormal α-synuclein and that NUB1 is able to inhibit α-synuclein aggregation in cultured cells. We therefore created transgenic (Tg) mice expressing both NUB1 and abnormal α-synuclein to investigate the role of NUB1 on degradation of abnormal α-synuclein in vivo. Immunohistochemical and biochemical studies confirmed that NUB1 was over-expressed in neurons of mice expressing NUB1 (NUB1 Tg), and both NUB1 and abnormal α-synuclein (double Tg). NUB1 levels were increased by 4.7-fold in NUB1 Tg mice compared with wild type mice. Unexpectedly, normal and abnormal α-synuclein levels were unchanged between abnormal α-synuclein Tg mice (Lewy body disease model mice) and double Tg mice, and pathological observations were almost similar between them. Finally, we found that the levels of insoluble α-synuclein were lower and those of some chaperone molecules were higher in double Tg mice compared with abnormal α-synuclein Tg mice. These results suggest that increased levels of NUB1 play a potential role in degradation of detergent-insoluble α-synuclein in vivo, although it is insufficient to degrade abnormal α-synuclein in Lewy body disease model mice.

Novel eosinophilic neuronal cytoplasmic inclusions in the external cuneate nucleus of humans.

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.