Efficacy and safety of tacrolimus as long-term monotherapy for myasthenia gravis.

The objective was to evaluate the long-term efficacy and safety of tacrolimus monotherapy in myasthenia gravis (MG) patients. Immunosuppressive drug-naïve MG patients were administered tacrolimus, followed by thymectomy in some of the cases according to the clinical guideline for MG. Additional aggressive immunosuppressive therapies were allowed if the patients without thymectomy did not achieve minimal manifestation (MM) or better status after 3 weeks of tacrolimus administration or in the thymectomized patients by 1-2 weeks after the operation (i.e., 1st evaluation). Of all 14 patients included in this study, 8 of them (57%) achieved MM or better status at the 1st evaluation, and the remaining 6 (43%), who had failed to gain MM or better status at the 1st evaluation, also achieved MM or better status with 1 course of aggressive immunosuppressive therapy. The quantitative MG (QMG) scores, MG-Activities of Daily Living (ADL) scales, and anti-acetylcholine receptor (AchR) antibody levels were significantly decreased at 6 months and maintained thereafter. At the end of the follow-up period (41-70 months), all patients were in MM or better status. None of the patients experienced severe adverse effects. Our small preliminary study indicates that long-term tacrolimus monotherapy is possibly effective and safe for MG patients.

Multiple Proteinopathies in Familial ALS Cases With Optineurin Mutations.

Optineurin (OPTN) is a causative gene in familial amyotrophic lateral sclerosis (ALS) with transactivation response element DNA-binding protein of 43 kDa (TDP-43) protein pathology. Here, we report multiple proteinopathies in familial ALS cases with OPTN mutations. We examined the TDP-43, tau, and α-synuclein pathology of ALS cases with OPTN mutations including 2 previously reported cases (Cases 1 and 2) and 1 newly autopsied case (Case 3) that was clinically diagnosed as ALS and Parkinson disease with a heterozygous E478G OPTN mutation. Pathologic examination of Case 3 showed motor neuron degeneration and depigmentation of the substantia nigra. Neurofibrillary tangles (NFTs) were seen in the hippocampus, pontine tegmentum, and spinal cord. Accumulation of multiple proteins including phosphorylated TDP-43-positive neuronal cytoplasmic inclusions, phosphorylated tau (AT8)-positive NFTs, and α-synuclein-positive Lewy bodies were observed in the substantia nigra. The other 2 cases had a similar distribution of tau pathology, but lacked synuclein pathology. Consecutive sections of Case 3 revealed pTDP-43, AT8, and α-synuclein-positive inclusions in the same neuron and double immunofluorescence staining showed aggregation of different proteins (tau and α-synuclein, or tau and TDP-43) in the same neuron. Our results support the notion that OPTN mutations may lead to multiple proteins aggregation and neuronal degeneration.

Zonisamide ameliorates levodopa-induced dyskinesia and reduces expression of striatal genes in Parkinson model rats.

To investigate the difference in results according to the mode of levodopa administration and the effect of zonisamide (ZNS), we analyzed the mRNA expression of dopaminergic and non-dopaminergic receptors in the striatum of Parkinson model rats in relation to the development of levodopa-induced dyskinesia (LID). Unilateral Parkinson model rats were subdivided into 4 groups and treated as follows: no medication (group N), continuous levodopa infusion (group C), intermittent levodopa injection (group I), and intermittent levodopa and ZNS injection (group Z). Two weeks after the treatment, LID was observed in group I and Z, but less severe in group Z. The level of both D1 and D2 receptor mRNAs was elevated in groups I and Z, but only D2 receptor mRNA expression was elevated in group C. Adenosine A2A receptor mRNA showed increased expression only in group I. The level of endocannabinoid CB1 receptor mRNA was elevated in groups N, C, and I, but not in group Z. Intermittent injection of levodopa caused LID, in association with elevated expression of D1 and A2A receptors. ZNS ameliorated the development of LID and inhibited up-regulation of A2A and CB1 receptors. Modulation of these receptors may lead to therapeutic approaches for dyskinesia.

Weight loss in the early stage of progressive supranuclear palsy.

OBJECTIVES: To clarify whether weight change in patients with Parkinson's disease (PD) or progressive supranuclear palsy (PSP) is caused by the disease itself or secondarily by other factors. MATERIALS AND METHODS: We conducted a retrospective analysis of 51 patients with PD and 14 patients with PSP, especially during the early stage of their diseases. All patients were independent in terms of their activities of daily living and did not have any feeding difficulty. RESULTS: The body mass index measured within 3 years after the disease onset did not show a significant difference between the two diseases. However, the subsequent weight was stable in patients with PD and significantly decreased in patients with PSP. CONCLUSIONS: Weight loss begins in the early stage of PSP, whereas dopaminergic treatment may contribute to keep weight in the early stage of PD through reduction of energy expenditure and/or improvement in appetite.

Early-onset Parkinson's Disease Associated with Chromosome 22q11.2 Deletion Syndrome.

We herein report the case of a 43-year-old man with a 4-year history of resting tremor and akinesia. His resting tremor and rigidity were more prominent on the left side. He also presented retropulsion. His symptoms responded to the administration of levodopa. The patient also had a cleft lip and palate, cavum vergae, and hypoparathyroidism. A chromosome analysis disclosed a hemizygous deletion in 22q11.2, and he was diagnosed with early-onset Parkinson's disease associated with 22q11.2 deletion syndrome. However, the patient lacked autonomic nerve dysfunction, and his cardiac uptake of (123)I-metaiodobenzylguanidine was normal, indicating an underlying pathological mechanism that differed to that of sporadic Parkinson's disease.

Successful treatment of paroxysmal tonic spasms with topiramate in a patient with neuromyelitis optica.

A 49-year-old woman with neuromyelitis optica (NMO) developed severe quadriplegia and frequent paroxysmal tonic spasms (PTS). Carbamazepine, although initially effective against PTS, caused drug eruption and she was unable to continue. PTS re-emerged after discontinuation of carbamazepine and hindered rehabilitation. Then topiramate was started, and PTS promptly disappeared. The patient became able to resume rehabilitation and her activity of daily life improved significantly. Carbamazepine and topiramate have a common pharmacological action to block voltage-gated sodium channels. The action may have contributed to inhibition of ephaptic transmission in the demyelinating lesions by NMO and eventually improved PTS.

An autopsy case of sporadic amyotrophic lateral sclerosis associated with the I113T SOD1 mutation.

A 64-year-old man noticed weakness in his arms and dyspnea upon exertion. Four months later he was admitted to our hospital, where muscle atrophy and hyperactive deep tendon reflexes in the arms were observed upon examination. A needle electromyograph study revealed acute and chronic denervation in the extremities, and he was diagnosed as having amyotrophic lateral sclerosis (ALS). Seven months after onset of the disease, he died of respiratory failure. Neuropathologically, neuronal cell loss was observed in the motor cortex, hypoglossal nuclei, cervical and lumbar anterior horns and Clarke's nuclei. Some of the remaining neurons contained neurofilamentous conglomerate inclusions (CIs). A small number of Lewy body-like hyaline inclusions (LBHIs) were also observed. No the Bunina bodies, skein-like inclusions or basophilic inclusions were detectable. Tract degeneration was moderate in the dorsal and ventral spinocerebellar tracts, mild in the pyramidal tract, but not discerned in the posterior column. Immunohistochemical examinations revealed that the CIs were strongly positive for phosphorylated neurofilament and moderately positive for ubiquitin and Cu/Zn superoxide dismutase 1 (SOD1). Moreover, a number of phosphorylated tau protein-positive globose neurofibrillary tangles (NFTs) and threads were observed in the periaqueductal gray matter, oculomotor nuclei and trochlear nuclei. Although the family history was negative for neuromuscular diseases, the neuropathological findings indicated features of familial ALS with a SOD1 mutation. In fact, DNA analysis of frozen-brain tissue revealed the presence of the I113T SOD1 mutation. This case represents the first one of this mutation in a patient who showed CIs as well as LBHIs in the motor neurons at the same time, in addition to the NFTs in the mesencephalic tegmentum.

Activation of transforming growth factor-ß/Smad signaling reduces aggregate formation of mislocalized TAR DNA-binding protein-43.

BACKGROUND: TAR DNA-binding protein of 43 kDa (TDP-43) is naturally located in the nucleus and has been identified as the major component of cytoplasmic ubiquitinated inclusions in patients with amyotrophic lateral sclerosis (ALS). We have reported that TDP-43 and phosphorylated Smad2 (pSmad2), an intracellular mediator protein of transforming growth factor-ß (TGFß) signaling, are co-localized within cytoplasmic inclusions in the anterior horn cells of sporadic ALS patients. OBJECTIVE: To investigate the possible pathophysiological linkage between pathologic cytoplasmic inclusions containing TDP-43 and TGFß/Smad signaling. METHODS: We replicated cytoplasmic aggregates of TDP-43 in HEK293T cells by transfecting the cells with a nuclear localization signal deletion mutant of TDP-43 and inhibiting proteasome activity, and assessed the effect of TGFß/Smad signaling on the cytoplasmic aggregate formation. RESULTS: The aggregates contained ubiquitinated, phosphorylated, and fragmented TDP-43, consistent with the essential features of the human pathology. Moreover, the aggregates were co-localized with pSmad2 under continuous TGFß stimulation. Overexpression of Smad2 reduced the amount of cytoplasmic aggregates in HEK293T cells, and TGFß stimulation augmented this reduction effect in a dose-dependent manner. CONCLUSION: Activation of the TGFß/Smad signaling system is protective against aggregate formation of cytoplasmically mislocalized TDP-43 and may be a potential therapeutic approach to delay progression of ALS.

Clinicopathologic study on an ALS family with a heterozygous E478G optineurin mutation.

We investigated a family manifesting amyotrophic lateral sclerosis (ALS) with a heterozygous E478G mutation in the optineurin (OPTN) gene. Clinically, slow deterioration of motor function, mood and personality changes, temporal lobe atrophy on neuroimaging, and bizarre finger deformity were noted. Neuropathologically, TAR DNA-binding protein 43 (TDP-43)-positive neuronal intracytoplasmic inclusions were observed in the spinal and medullary motor neurons. In these cells, the immunoreactivity of nuclear TDP-43 was reduced. Consecutive sections revealed that the inclusions were also reactive with anti-ubiquitin and anti-p62 antibodies, but noticeably negative for OPTN. In addition, TDP-43/p62-positive glial cytoplasmic inclusions (GCIs) were scattered throughout the spinal cord and the medullary motor nuclei. Furthermore, Golgi fragmentation was identified in 70% of the anterior horn cells (AHCs). The presence of AHCs with preserved nuclear TDP-43 and a fragmented Golgi apparatus, which are unrecognizable in sporadic ALS, indicates that patients with the E4787G OPTN mutation would manifest Golgi fragmentation before loss of nuclear TDP-43. In the neocortex, GCIs were sparsely scattered among the primary motor and temporal cortices, but no neuronal TDP-43-positive inclusions were detected. In the amygdala and the ambient gyrus, argyrophilic grains and ballooned neurons were seen. The thorough neuropathologic investigations performed in this work demonstrated that OPTN-positive inclusion bodies, if any, were not prominent. We postulate that optineurinopathy is closely linked with TDP-proteinopathy and speculate that this heterozygous E478G mutation would cause ALS by acting through a dominant-negative mechanism.

Myonuclear breakdown in sporadic inclusion body myositis is accompanied by DNA double strand breaks.

Rimmed vacuoles in sporadic inclusion body myositis (s-IBM) contain nuclear remnants. We sought to determine if the nuclear degeneration seen in s-IBM is associated with DNA damage. In muscle biopsy specimens from ten patients with s-IBM and 50 controls, we immunolocalized 1) phosphorylated histone H2AX (γ-H2AX), which is a sensitive immunocytochemical marker of DNA double-strand breaks and 2) DNA-PK, which is an enzyme involved in double-strand break repair. In s-IBM, vacuolar peripheries often showed strong immunoreactivity to γ-H2AX and the three components of DNA-PK (DNA-PKcs, Ku70, and Ku80). A triple fluorescence study of Ku70, emerin, and DNA displayed nuclear breakdown and it suggested impaired nuclear incorporation of Ku70. The percentage of positive nuclei for γ-H2AX was significantly higher in vacuolated fibers than non-vacuolated fibers in s-IBM, or fibers in polymyosits. We hypothesize that a dysfunction of nuclear envelope may cause nuclear fragility, double-strand breaks and impaired nuclear transport in s-IBM.

[A case of cerebellar syndrome associated with HIV infection].

A 36-year-old man was hospitalized because of subacutely progressive gait disturbance. Neurological examination disclosed severe ataxia of gait and trunk and moderate ataxia of the four limbs, without signs of cognitive impairment. There were no manifestations of systemic infections. Brain MRI showed mild atrophy of the cerebellar vermis and hemispheres. Extensive laboratory search failed to disclose the cause of subacute ataxia. Cerebellar ataxia progressed, leading to the patient becoming wheelchair-bound two months after admission, when PCR analysis of the cerebrospinal fluid was positive for Epstein-Barr, JC, and hepatitis B viruses. In addition, the quantity of serum HIV1-RNA was 2.9 x 10(4) copies, the absolute count of CD4+ lymphocyte was 28/mm3, and the CD4/CD8 ratio was 0.04, despite clear denials by both the patient and his wife regarding any apparent infectious opportunities. Accordingly thereafter, highly active antiretroviral therapy was initiated. Several weeks after the initiation of therapy, ataxia stabilized with disappearance of serum HIV and cerebrospinal fluid JCV viral load. He returned to his occupation 20 months after disease onset without progression of ataxia or development of other neurological dysfunctions including dementia. We could not establish the exact pathogenesis of ataxia in this patient It could have been primary cerebellar degeneration caused by HIV, or the other viruses detected (EBV, JCV) or autoimmune mechanisms caused by these viruses. However, HIV infection should be considered as an etiology in clinical setting of subacute ataxia, particularly in a young or immunocompromised patient.

Nuclear contour irregularity and abnormal transporter protein distribution in anterior horn cells in amyotrophic lateral sclerosis.

The nucleocytoplasmic transport system is essential for maintaining cell viability; transport of proteins and nucleic acids between the nucleus and the cytoplasm occurs through nuclear pore complexes (NPCs). In this study, we examined the immunohistochemical distribution of the major protein components of NPCs, Nup62, Nup88, and Nup153, in spinal cords from controls and patients with sporadic or familial amyotrophic lateral sclerosis (SALS or FALS) and its mouse model. In control subjects, immunolabeling on the nuclear envelopes of anterior horn cells (AHCs) was invariably smooth and continuous, whereas in SALS and FALS patients, the AHCs predominantly showed irregular nuclear contours. Double immunofluorescence staining demonstrated that in SALS patients, importin-beta immunoreactivity was absent in the nuclei in a subset of AHCs; in these cells, Nup62 immunolabeling of nuclear membrane was invariably irregular, suggesting that there was dysfunctional nucleocytoplasmic transport in those AHCs. In the mouse model, Nup62-immunolabeled AHCs with irregular nuclear contours were predominant as early as the presymptomatic stage and the contours became progressively discontinuous along with disease development. Together, these observations suggest that dysfunctional nucleocytoplasmic transport may underlie the pathogenesis of ALS.

Intra-bone marrow-bone marrow transplantation slows disease progression and prolongs survival in G93A mutant SOD1 transgenic mice, an animal model mouse for amyotrophic lateral sclerosis.

It has been reported that bone marrow transplantation (BMT) has clinical effects on not only hematopoietic diseases and autoimmune diseases but also solid malignant tumors and metabolic diseases. We have found that intra-bone marrow-bone marrow transplantation (IBM-BMT) is superior to conventional intravenous BMT, since IBM-BMT enables rapid recovery of donor hematopoiesis and reduces the extent of graft-versus-host disease (GVHD). In this experiment, we examined the effects of IBM-BMT on symptomatic G93A mutant SOD1 transgenic mice (mSOD1 Tg mice), a model mouse line for amyotrophic lateral sclerosis (ALS). Symptomatic mSOD1 Tg mice (12 weeks old) were irradiated with 6Gyx2 at a 4-hour interval, one day before IBM-BMT. The mice were transplanted with bone marrow cells (BMCs) from 12-wk-old eGFP-transgenic C57BL/6 mice (eGFP Tg mice) or BMCs from 12-wk-old mSOD1 Tg mice. The ALS model mice transplanted with BMCs from eGFP Tg mice showed longer survival and slower disease progression than those transplanted with BMCs from mSOD1 Tg mice or untreated mSOD1 Tg mice. There was a significantly high number of eGFP(+) cells in the anterior horn of the spinal cord of the mSOD1 Tg mice transplanted with BMCs of eGFP Tg mice, some of which expressed Iba-1, a marker of microglia, although they did not differentiate into neural cells. These results suggest that the replacement with normal hematopoietic cells improved the neural cell environment, thereby slowing the progression of the disease.

Screening for TARDBP mutations in Japanese familial amyotrophic lateral sclerosis.

TAR-DNA-binding protein 43 (TDP-43), encoded by the TARDBP gene on chromosome 1p36.22, has been identified as the major pathological protein in abnormal inclusions in neurons and glial cells in sporadic amyotrophic lateral sclerosis (SALS), SOD1-negative familial ALS (FALS) and frontotemporal lobar dementia (FTLD). Twenty mutations of TARDBP in SOD1-negative FALS and SALS cases have been reported so far. To investigate the presence and frequency of TARDBP mutations in Japanese SOD1-negative FALS patients, we performed mutational screening of TARDBP in 30 SOD1-negative FALS patients. An N352S mutation was found in one case of FALS, but no TARDBP mutations were found in cases of SALS. It was thought that this mutation increases TDP-43 phosphorylation. This might lead to impaired nuclear cytoplasmic transport or protein-protein interaction, thereby leading to TDP-43 accumulation.

The first Japanese patient with variant Creutzfeldt-Jakob disease (vCJD).

Eleven years after a brief visit to some European countries, a 48-year-old Japanese man developed writing difficulty, irritability and general fatigue. Then he complained of dysesthetic pains in his legs, for which benzodiazepines were prescribed. However, at the time pulvinar sign was retrospectively confirmed on brain MRI. Eighteen months after the onset, his gait became ataxic with rapid deterioration of mental status over the following several months. Thirty-one months after the onset, he became akinetic and mute with periodic synchronous discharges on EEG, and died at the age of 51. The total clinical course was approximately 43 months. Pathological examination revealed the characteristic alterations of spongiform encephalopathy, severe in the thalamus, moderate but widely spread in the cerebral cortices, and moderate in the cerebellum. Abundant amyloid plaques were easily identified in the cerebral cortex and the cerebellum on HE staining. Immunohistochemistry for abnormal prion protein (PrP(sc)) confirmed amyloid plaques in several forms, such as florid, uni- and multi-centric plaques as well as perineuronal and periaxonal deposits in the basal ganglia and synaptic patterns in the thalami. A Western blotting study identified type 2B protease-resistant PrP. This is the first Japanese patient who was definitely diagnosed as variant Creutzfeldt-Jakob disease (vCJD). The pathological findings were similar to those of previous reports of vCJD in the UK. However, the changes were much more severe both in degree and distribution, probably due to a longer duration of the illness than those in the UK.

Treatment with edaravone, initiated at symptom onset, slows motor decline and decreases SOD1 deposition in ALS mice.

Edaravone is a free-radical scavenger, an agent being widely used for cerebral ischemia in Japan. To evaluate its efficacy for possible treatment of amyotrophic lateral sclerosis (ALS), we performed a randomized blind trial in ALS model mice. After identification of the clinical onset in each female G93A mutant SOD1 transgenic mouse, we intraperitoneally administered multiple doses of edaravone to the mice and observed their motor symptoms. We also counted the number of lumbar motoneurons, determined the 3-nitrotyrosine/tyrosine ratio, and evaluated the abnormal SOD1 aggregation in the spinal cord at the 10th day after the edaravone injection. Edaravone significantly slowed the motor decline of the transgenic mice. The remaining motoneurons were significantly preserved in the higher-dose edaravone-administered group, and the 3-nitrotyrosine/tyrosine ratios were reduced dose-dependently. Intriguingly, the area of abnormal SOD1 deposition in the spinal cord was significantly decreased in the higher-dose edaravone-administered group. Our results indicate that edaravone was effective to slow symptom progression and motor neuron degeneration in the ALS model mice. These favorable actions might be attributable to the yet unidentified mechanism responsible for reducing the deposition of mutant SOD1.

Immunohistochemical identification of messenger RNA-related proteins in basophilic inclusions of adult-onset atypical motor neuron disease.

This report concerns an immunohistochemical investigation on RNA-related proteins in the basophilic inclusions (BIs) from patients with adult-onset atypical motor neuron disease. Formalin-fixed, paraffin-embedded sections of the motor cortex and the lumbar spinal cord were examined. The BIs appeared blue in color with H&E and Nissl stain, and pink with methylgreen-pyronin stain. Ribonuclease pretreatment abolished the methylgreen-pyronin staining, suggesting that the BIs contained RNA. Immunohistochemically, the BIs were distinctly labeled with the antibodies against poly(A)-binding protein 1, T cell intracellular antigen 1, and ribosomal protein S6. These proteins are essential constituents of stress granules. In contrast, the BIs were not immunoreactive for ribosomal protein L28 and decapping enzyme 1, which are core components of transport ribonucleoprotein particles and processing bodies, respectively. Moreover, the BIs were not immunopositive for TDP-43. Our results imply that translation attenuation could be involved in the processes of BI formation in this disorder.

Phosphorylated Smad2/3 immunoreactivity in sporadic and familial amyotrophic lateral sclerosis and its mouse model.

Phosphorylated Smad2/3 (pSmad2/3), the central mediators of transforming growth factor (TGF)-beta signaling, were recently identified in tau-positive inclusions in certain neurodegenerative disorders. To clarify whether the localization of pSmad2/3 is altered in amyotrophic lateral sclerosis (ALS), we immunohistochemically examined spinal cords from sporadic ALS (SALS), from familial ALS (FALS) patients with the A4V mutation in their Cu/Zn superoxide dismutase (SOD1) gene, and from G93A mutant SOD1 transgenic (mSOD1 Tg) mice. In control spinal cords, pSmad2/3 immunoreactivity was observed exclusively in neuronal and glial nuclei. In SALS and FALS patients the nuclei showed increased immunoreactivity for pSmad2/3. Noticeably, round hyaline inclusions (RHIs) and skein-like inclusions of SALS patients were immunoreactive for pSmad2/3. Double immunofluorescence staining for pSmad2/3 and transactive response-DNA-binding protein (TDP)-43 revealed co-localization of these proteins within RHIs. In contrast, Bunina bodies in SALS and Lewy body-like hyaline inclusions (LBHIs) in FALS were devoid of labeling for pSmad2/3. Similarly, in the mSOD1 Tg mice pSmad2/3 immunoreactivity was increased in the nuclei, while LBHIs were not labeled. These findings suggest increased TGF-beta-Smad signaling in SALS, FALS, and mSOD1 Tg mice, as well as impaired TGF-beta signal transduction in RHI-bearing neurons of SALS patients, presumably at the step of pSmad2/3 translocation into the nucleus. The pathomechanisms, including the process of inclusion development, appears to be different between SALS and mSOD1-related FALS or Tg mice.

Diagnostic clues and more from photographs.

During over 50 years of the first author's career in neuropathology at Montefiore Medical Center in New York, we have come across certain interesting neuropathological findings. In this communication, some photographs showing macroscopic, microscopic and electron microscopic significant findings are selected to illustrate usefulness not only for the diagnosis but also for understanding of the nervous system. The six topics presented in this paper are: (i) unattached presynaptic terminals in cerebellar neuroblastoma; (ii) neurofibrillary tangle formation in the nucleus basalis of Meynert ipsilateral to a massive cerebral infarct; (iii) orderly arrangement of tumor cells in leptomeningeal carcinomatosis; (iv) interface between craniopharyngioma and brain tissue; (v) neurofibrillary tangles and Lewy bodies in a single neuron; and (vi) Cu/Zn superoxide dismutase positive Lewy body-like hyaline inclusions in anterior horn cells in familial motor neuron diseases. Analyses of these findings are presented for an educational purpose.