Transcranial Magnetic Stimulation with the Maximum Voluntary Muscle Contraction Facilitates Motor Neuron Excitability and Muscle Force

Three trials of transcranial magnetic stimulation (TMS) during the maximum voluntary muscle contraction (MVC) were repeated at 15-minute intervals for 1 hour to examine the effects on motor evoked potentials (MEPs) in the digital muscles and pinching muscle force before and after 4 high-intensity TMSs (test 1 condition) or sham TMS (test 2 condition) with MVC. Under the placebo condition, real TMS with MVC was administered only before and 1 hour after the sham TMS with MVC. Magnetic stimulation at the foramen magnum level (FMS) with MVC was performed by the same protocol as that for the test 2 condition. As a result, MEP sizes in the digital muscles significantly increased after TMS with MVC under test conditions compared with the placebo conditions (P < 0.05). Pinching muscle force was significantly larger 45 minutes and 1 hour after TMS with MVC under the test conditions than under the placebo condition (P < 0.05). FMS significantly decreased MEP amplitudes 60 minutes after the sham TMS with MVC (P < 0.005). The present results suggest that intermittently repeated TMS with MVC facilitates motor neuron excitabilities and muscle force. However, further studies are needed to confirm the effects of TMS with MVC and its mechanism

Genetic screening for malignant hyperthermia and comparison of clinical symptoms in Japan

Malignant hyperthermia (MH) is an anaesthetic complication that causes an abnormal hypermetabolic state. RYR1 encoding ryanodine receptors of the sarcoplasmic reticulum and CACNA1S encoding α subunits of dihydropyridine receptors are known to be associated with MH pathogenicity. We performed genetic screening using next-generation sequencing to evaluate the prevalence of genes associated with MH pathogenicity and clinical symptoms. This was a retrospective cohort study wherein next-generation sequencing data of 77 families diagnosed with MH predisposition by calcium-induced calcium release (CICR) tests from 1995 to 2019 was used to search for RYR1 and CACNA1S variants. Furthermore, the clinical symptoms and predisposition tests in participants with RYR1 and CACNA1S variants were compared. In the 77 families, 44.2%, 7.8%, and 48.1% individuals had RYR1, CACNA1S, and neither RYR1 nor CACNA1S variants, respectively. Clinically significant differences were found in the maximum body temperature, maximum elevated body temperature for 15 min, creatinine kinase level, and CICR rate between the RYR1 and CACNA1S groups. The prevalence of pathogenic CACNA1S variants appears to be prominent in Japan. The severity of clinical symptoms and the CICR rate were greater in individuals with RYR1 variants than in those with CACNA1S variants, likely due to more direct regulation of calcium levels by ryanodine receptors than by dihydropyridine receptors. Genetic analysis of MH in future studies may help identify other genes associated with MH, which will further clarify the relationship between genotypes and MH symptoms and contribute to safer anaesthesia practice.This study was supported by a Grant-in-Aid for Young Scientists (grant number: 17K16733 to Y.N. and 20K17783 to R.K.) from the Japan Society for the Promotion of Science and by the Takeda Science Foundation (H.K.)

Co-morbidity of progressive supranuclear palsy and amyotrophic lateral sclerosis : a clinical-pathological case report

Background: The coexistence of distinct neurodegenerative diseases in single cases has recently attracted greater attention. The phenotypic co-occurrence of progressive supranuclear palsy (PSP) and amyotrophic lateral sclerosis (ALS) has been documented in several cases. That said, the clinicopathological comorbidity of these two diseases has not been demonstrated. Case presentation: A 77-year-old man presented with gait disturbance for 2 years, consistent with PSP with progressive gait freezing. At 79 years old, he developed muscle weakness compatible with ALS. The disease duration was 5 years after the onset of PSP and 5months after the onset of ALS. Neuropathological findings demonstrated the coexistence of PSP and ALS. Immunohistochemical examination confirmed 4-repeat tauopathy, including globose-type neurofibrillary tangles, tufted astrocytes, and oligodendroglial coiled bodies as well as TAR DNA-binding protein 43 kDa pathology in association with upper and lower motor neuron degeneration. Immunoblotting showed hyperphosphorylated full-length 4-repeat tau bands (64 and 68 kDa) and C-terminal fragments (33 kDa), supporting the diagnosis of PSP and excluding other parkinsonian disorders, such as corticobasal degeneration. Genetic studies showed no abnormalities in genes currently known to be related to ALS or PSP. Conclusions: Our case demonstrates the clinicopathological comorbidity of PSP and ALS in a sporadic patient. The possibility of multiple proteinopathies should be considered when distinct symptoms develop during the disease course

Optineurin regulates osteoblastogenesis through STAT1

A sophisticated and delicate balance between bone resorption by osteoclasts and bone formation by osteoblasts regulates bone metabolism. Optineurin (OPTN) is a gene involved in primary open-angle glaucoma and amyotrophic lateral sclerosis. Although its function has been widely studied in ophthalmology and neurology, recent reports have shown its possible involvement in bone metabolism through negative regulation of osteoclast differentiation. However, little is known about the role of OPTN in osteoblast function. Here, we demonstrated that OPTN controls not only osteoclast but also osteoblast differentiation. Different parameters involved in osteoblastogenesis and osteoclastogenesis were assessed in Optn−/- mice. The results showed that osteoblasts from Optn−/- mice had impaired alkaline phosphatase activity, defective mineralized nodules, and inability to support osteoclast differentiation. Moreover, OPTN could bind to signal transducer and activator of transcription 1 (STAT1) and regulate runt-related transcription factor 2 (RUNX2) nuclear localization by modulating STAT1 levels in osteoblasts. These data suggest that OPTN is involved in bone metabolism not only by regulating osteoclast function but also by regulating osteoblast function by mediating RUNX2 nuclear translocation via STAT1

Serum microRNA expression profiling in patients with multiple system atrophy

Abstract Multiple system atrophy (MSA) is a sporadic neurodegenerative disease that is pathologically characterized by α‑synuclein positive glial cytoplasmic inclusions in oligodendrocytes. The clinical diagnosis of MSA is often challenging as there are no established biomarkers and diagnoses are now based on clinical findings alone. At present, the etiology and pathogenesis of MSA are unclear. It has been reported that dysregulation of microRNA (miRNA/miR) serves an important role in neurodegenerative disorders including Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. The miRNA profile of patients with MSA remains to be established. The present study investigated the serum miRNA expression level of 10 patients with MSA, using microarray chips including 668 miRNAs. It was identified that 50 miRNAs were significantly upregulated and 17 miRNAs were significantly downregulated in the serum of the patients with MSA. The most upregulated miRNA was miR‑16, which may induce the accumulation of α‑synuclein. The target genes of some miRNAs upregulated in MSA (including miR‑17, 20a, 24, 25, 30d and 451) were associated with autophagy‑associated molecules. The present study concluded that the expression pattern of miRNAs may be a clinical biomarker for MSA and targeting these miRNAs may provide a novel treatment for MSA

Transfection of T-Box Transcription Factor <i>BRACHYURY</i> and <i>SOX2</i> Synergistically Promote Self-Renewal and Invasive Phenotype in Oral Cancer Cells

Recent studies suggest that epithelial&#8315;mesenchymal transition (EMT) correlates with cancer metastasis. In addition, there is growing evidence of the association of EMT with cancer stem cells (CSCs). Recently, we showed that the T-box transcription factor BRACHYURY could be a strong regulator of EMT and the CSC phenotype, which were effectively suppressed by a BRACHYURY knockdown in an adenoid cystic carcinoma cell line. In this study, we further tested whether BRACHYURY is a regulator of cancer stemness by means of forced expression of BRACHYURY in oral cancer cell lines. BRACHYURY, SOX2, or both were stably transfected into oral carcinoma cell lines. We analysed these transfectants with respect to self-renewal phenotypes using a sphere-formation assay, and we assessed the expression levels of EMT markers and stem cell markers using real-time reverse transcription-polymerase chain reaction (RT-PCR). Cell migration and invasiveness in vitro were evaluated using a wound healing assay and a tumour cell dissemination assay, respectively. Forced expression of BRACHYURY or SOX2 slightly increased expression of EMT and stem cell markers and the self-renewal phenotype. The expression levels, however, were much lower compared to those of cancer stem cell-like cells. Forced co-expression of BRACHYURY and SOX2 strongly upregulated EMT and stem cell markers and the self-renewal phenotype. Cell migration and invasiveness in vitro were also remarkably enhanced. These synergistic effects increased expression levels of FIBRONECTIN, SNAIL, SLUG, ZEB1, and TGF-&#946;2. In particular, the effects on FIBRONECTIN and TGF-&#946;2 were significant. We found that BRACHYURY and SOX2 synergistically promote cancer stemness in oral cancer cells. This finding points to the importance of gene or protein networks associated with BRACHYURY and SOX2 in the development and maintenance of the CSC phenotype

Inhibition of neuronal nitric-oxide synthase by phosphorylation at Threonine1296 in NG108-15 neuronal cells

AbstractWe demonstrate that neuronal nitric-oxide synthase (nNOS) is directly inhibited through the phosphorylation of Thr1296 in NG108-15 neuronal cells. Treatment of NG108-15 cells expressing nNOS with calyculin A, an inhibitor of protein phosphatase 1 and 2A, revealed a dose-dependent inhibition of nNOS enzyme activity with concomitant phosphorylation of Thr1296 residue. Cells expressing a phosphorylation-deficient mutant in which Thr1296 was changed to Ala proved resistant to phosphorylation and suppression of NOS activity. Mimicking phosphorylation mutant of nNOS in which Thr1296 is changed to Asp showed a significant decrease in nNOS enzyme activity, being competitive with NADPH, relative to the wild-type enzyme. These data suggest that phosphorylation of nNOS at Thr1296 may involve the attenuation of nitric oxide production in neuronal cells through the decrease of NADPH-binding to the enzyme