Papers by Noriyuki Nishida
Bioengineering
Stem cell therapy for ischemic stroke holds great promise for the treatment of neurological impai... more Stem cell therapy for ischemic stroke holds great promise for the treatment of neurological impairment and has moved from the laboratory into early clinical trials. The mechanism of action of stem cell therapy includes the bystander effect and cell replacement. The bystander effect plays an important role in the acute to subacute phase, and cell replacement plays an important role in the subacute to chronic phase. Intraarterial (IA) transplantation is less invasive than intraparenchymal transplantation and can provide more cells in the affected brain region than intravenous transplantation. However, transplanted cell migration was reported to be insufficient, and few transplanted cells were retained in the brain for an extended period. Therefore, the bystander effect was considered the main mechanism of action of IA stem cell transplantation. In most clinical trials, IA transplantation was performed during the acute and subacute phases. Although clinical trials of IA transplantation...
Prions are unconventional pathogens that encode the pathogenic information in conformations of th... more Prions are unconventional pathogens that encode the pathogenic information in conformations of the constituent abnormal isoform of prion protein (PrPSc), independently of the nucleotide genome. Therefore, conformational diversity of PrPSc underlies the existence of many prion strains and species barriers of prions, although the conformational information is extremely limited. Interestingly, differences between polymorphic or species-specific residues responsible for the species/strain barriers are often caused by conservative replacements between hydrophobic amino acids. This implies that subtle differences among hydrophobic amino acids are significant for PrPSc structures. Here, we analyzed the influence of different hydrophobic residues on the structures of an in-register parallel β-sheet amyloid of α-synuclein (αSyn) using molecular dynamics (MD) simulation, and applied the knowledge from the αSyn amyloid to modeling a local structure of human PrPSc encompassing residues 107–143....
Nuclear Medicine and Biology, 2020
Introduction: Prion diseases are fatal neurodegenerative disorders caused by the deposition of ab... more Introduction: Prion diseases are fatal neurodegenerative disorders caused by the deposition of abnormal prion protein aggregates (PrP Sc ) in the central nervous system. This study aimed to evaluate the use of iodinated pyridyl benzofuran (IPBF) derivatives as single-photon emission computed tomography (SPECT) probes for the detection of cerebral PrP Sc deposits. Methods: In vitro binding assays of IPBF derivatives were carried out in the recombinant mouse prion protein (rMoPrP) and brain sections of mouse-adapted bovine spongiform encephalopathy (mBSE)-infected mice. SPECT imaging of 5-(5-[ 123 I]iodobenzofuran-2yl)-N-methylpyridin-2-amine ([ 123 I]IPBF-NHMe) was performed on mBSE-infected and mock-infected mice. Results: Fluorescence microscopy results showed that fluorescence signals of IPBF derivatives corresponded to the thioflavin-T positive amyloid deposits of PrP Sc in the Fuchigami et al. Page 4/38 brain sections of mouse-adapted bovine spongiform encephalopathy (mBSE)-infected mice. Among the IPBF derivatives, 5-(5-iodobenzofuran-2-yl)-N-methylpyridin-2-amine (IPBF-NHMe) exhibited the highest binding affinity to the recombinant mouse prion protein (rMoPrP) aggregates with a Ki of 14.3 nM. SPECT/computed tomography (CT) imaging and ex vivo autoradiography demonstrated that the [ 123 I]IPBF-NHMe distribution in brain tissues of mBSE-infected mice co-localized with PrP Sc deposits. Conclusion: [ 123 I]IPBF-NHMe appears to be a prospective SPECT tracer for monitoring prion deposits in living brain tissues.
Stroke, 2013
Background and Purpose— Intra-arterial cell transplantation offers a novel therapeutic strategy f... more Background and Purpose— Intra-arterial cell transplantation offers a novel therapeutic strategy for stroke; however, it remains unclear how the timing of cell administration affects cell distribution, brain repair processes and functional recovery. Here, we investigate the hypothesis that the timing of cell transplantation changes the behavior of the cell graft and the host environment in a way that affects functional recovery. Methods— Rats received human mesenchymal stem cells (hMSCs) via the internal carotid artery at 1, 4 or 7 days (D1, D4 or D7) after middle cerebral artery occlusion and reperfusion. Animals were sacrificed at various time points to assess cell distribution in correlation with the host cerebral hemodynamics, serum levels of matrix metallopeptidase-9 (MMP-9), infiltration of activated microglia, expression of brain derived neurotrophic factor (BDNF), angiogenesis, presence of reactive astrocytes, and neurological recovery. Results— hMSCs were widely distributed ...
The Molecular Biology Society of Japan, 2016
Neurotherapeutics, 2020
The accumulation of abnormal prion protein (PrP Sc) produced by the structure conversion of PrP (... more The accumulation of abnormal prion protein (PrP Sc) produced by the structure conversion of PrP (PrP C) in the brain induces prion disease. Although the conversion process of the protein is still not fully elucidated, it has been known that the intramolecular chemical bridging in the most fragile pocket of PrP, known as the "hot spot," stabilizes the structure of PrP C and inhibits the conversion process. Using our original structure-based drug discovery algorithm, we identified the low molecular weight compounds that predicted binding to the hot spot. NPR-130 and NPR-162 strongly bound to recombinant PrP in vitro, and fragment molecular orbital (FMO) analysis indicated that the high affinity of those candidates to the PrP is largely dependent on nonpolar interactions, such as van der Waals interactions. Those NPRs showed not only significant reduction of the PrP Sc levels but also remarkable decrease of the number of aggresomes in persistently prion-infected cells. Intriguingly, treatment with those candidate compounds significantly prolonged the survival period of prion-infected mice and suppressed prion disease-specific pathological damage, such as vacuole degeneration, PrP Sc accumulation, microgliosis, and astrogliosis in the brain, suggesting their possible clinical use. Our results indicate that in silico drug discovery using NUDE/DEGIMA may be widely useful to identify candidate compounds that effectively stabilize the protein.
Cellular and Molecular Neurobiology, 2020
Diversity of prion strains is one of the most mysterious traits of prions because they are mere a... more Diversity of prion strains is one of the most mysterious traits of prions because they are mere aggregates of abnormally-folded forms of single protein species, prion protein (PrPSc), without genome. Although the strain-specific properties are hypothesized to be enciphered in the strain-specific structures of PrPSc instead of nucleotide genome, specifically what structure can code the information remains an enigma due to the incompatibility of PrPSc with structural analyses. Although the strain diversity was regarded as unique to prions, recently other disease-associated amyloids of α-synuclein (αSyn) or tau are also reported to have “strains”. As detailed structures of αSyn amyloid are already identified and the properties of mutant αSyn associated with familial Parkinson’s diseases, e.g. A53T, H50Q, and G51D, have been characterized, structure-phenotype relations of this type of amyloid could be investigated by using the αSyn amyloid as a model. Here we intensively investigated th...
The Journal of biological chemistry, Jan 21, 2018
A funding source was inadvertently omitted. The Takeda Science Foundation should have been acknow... more A funding source was inadvertently omitted. The Takeda Science Foundation should have been acknowledged in the grant footnote.
The Journal of Nuclear Medicine, 2014
Biochemical and Biophysical Research Communications, 2020
Cellular prion protein (PrP) is a membrane protein that is highly conserved among mammals and mai... more Cellular prion protein (PrP) is a membrane protein that is highly conserved among mammals and mainly expressed on the cell surface of neurons. Despite its reported interactions with various membrane proteins, no functional studies have so far been carried out on it, and its physiological functions remain unclear. Neuronal cell death has been observed in a PrP-knockout mouse model expressing Doppel protein, suggesting that PrP might be involved in Ca 2þ signaling. In this study, we evaluated the binding of PrP to metabotropic glutamate receptor 1 (mGluR1) and found that wild-type PrP (PrP-wt) and mGluR1 co-immunoprecipitated in dual-transfected Neuro-2a (N2a) cells. Fluorescence resonance energy transfer analysis revealed an energy transfer between mGluR1-Cerulean and PrP-Venus. In order to determine whether PrP can modulate mGluR1 signaling, we performed Ca 2þ imaging analyses following repetitive exposure to an mGluR1 agonist. Agonist stimulation induced synchronized Ca 2þ oscillations in cells coexpressing PrP-wt and mGluR1. In contrast, N2a cells expressing PrP-DN failed to show liganddependent regulation of mGluR1-Ca 2þ signaling, indicating that PrP can bind to mGluR1 and modulate its function to prevent irregular Ca 2þ signaling and that its N-terminal region functions as a molecular switch during Ca 2þ signaling.
Stroke, 2017
Background and purpose: Cell transplantation therapy holds great potential to improve impairments... more Background and purpose: Cell transplantation therapy holds great potential to improve impairments after stroke. However, the importance of donor age on therapeutic efficacy is uncertain. We investigate regenerative capacity of transplanted cells focusing on donor age (young vs. old) for ischemic stroke. Methods: The value of platelet-derived growth factor (PDGF)-BB secreted from human mesenchymal stem cells (hMSC) was analyzed regarding in two age groups; young (20-30 years) and old (57-65 years) in vitro. Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion, and received young or old hMSC trans-arterially at 24 h after stroke. Functional recovery was assessed with modified neurological severity score (mNSS). Structural recovery was assessed on neovascularization and endogenous cell migration as well as trophic factor secretion. Results: The value of PDGF-BB was significantly higher in young hMSC (40.47±4.29 pg/ml/10 4 cells) than that in old hMSC (2...
Neuropathology, 2021
We report the general autopsy findings of abnormal prion protein (PrP) deposits with their seedin... more We report the general autopsy findings of abnormal prion protein (PrP) deposits with their seeding activities, as assessed by the real‐time quaking‐induced conversion (RT‐QuIC) method, in a 72‐year‐old female patient with sporadic Creutzfeldt–Jakob disease (sCJD). At 68 years of age, she presented with gait disturbance and visual disorders. Electroencephalography showed periodic synchronous discharge. Myoclonus was also observed. A genetic test revealed that PRNP codon 129 was methionine/methionine (MM). She died of pneumonia three years and four months after disease onset, and a general autopsy was performed. The brain weighed 650 g and appeared markedly atrophic. Immunohistochemistry for PrP revealed synaptic PrP deposits and coarse PrP deposits in the cerebral cortices, basal ganglia, cerebellum, and brainstem. Western blot analysis identified type 1 proteinase‐K‐resistant PrP in frontal cortex samples. PrP deposits were also observed in systemic organs, including the femoral nerve, psoas major muscle, abdominal skin, adrenal medulla, zona reticularis of the adrenal gland, islet cells of the pancreas, and thyroid gland. The RT‐QuIC method revealed positive seeding activities in all examined organs, including the frontal cortex, femoral nerve, psoas major muscle, scalp, abdominal skin, adrenal gland, pancreas, and thyroid gland. The following 50% seeding dose (SD50) values were 9.5 (frontal cortex); 8 ± 0.53 (femoral nerve); 7 ± 0.53 (psoas major muscle); and 7.88 ± 0.17 (scalp). The SD50 values for the adrenal gland, dermis, pancreas, and thyroid gland were 6.12 ± 0.53, 5.25, 4.75, and 4.5, respectively. PrP deposits in general organs may be associated with long‐term disease duration. This case indicated the necessity for general autopsies in sCJD cases to establish strict infection control procedures for surgical treatment and to examine certain organs.
Neurobiology of Disease, 2021
BACKGROUND The neuropathology of sporadic Creutzfeldt-Jakob disease (sCJD) is usually investigate... more BACKGROUND The neuropathology of sporadic Creutzfeldt-Jakob disease (sCJD) is usually investigated using formalin-fixed and formic acid-treated brain tissue. However, formalin and formic acid treatment can interfere with immunostaining of abnormal prion protein. Therefore, there is a need for biochemical methods other than immunostaining to investigate abnormal prion protein in postmortem tissue. We developed RT-QuIC to quantitate the seeding activity (SD50) of sCJD brain tissue treated with formalin and formic acid. METHODS We used endpoint RT-QuIC assays to analyze SD50 in formalin-fixed brain tissue from 19 sCJD patients (14 MM1 cases, 3 MM2-thalamic form [MM2T] cases and 2 MM2-cortical form [MM2C] cases) diagnosed according to Parchi's classification. We assessed SD50 in brains after incubation in formalin solution for over 1 month, and after treating formalin-fixed brain tissue with formic acid. We also examined how the SD50 values from formalin-fixed brain samples compared with neuropathological and immunohistochemical findings. RESULTS The SD50 values of formalin-fixed brain samples from 14 MM1 cases, 2 MM2C cases, and 2 MM2T cases were 107.77±0.57/g tissue, 107.44±0.24/g tissue and 106.00±0.77/g tissue, respectively. The average SD50 value in MM1 unfixed brains decreased by 102.04 after formalin fixation for 1 month. In MM1 cases, after combined formalin and formic acid treatment, the SD50 value was reduced by approximately 105.16 compared with that of unfixed tissue. The SD50 values of formalin-fixed tissue showed a consistent pattern with the neuropathological findings in most brain regions examined. CONCLUSION RT-QuIC enables the study of formalin-fixed brain tissue from sCJD patients that has not previously been amenable to analysis.
Brain, 2019
Infectious prions comprising abnormal prion protein, which is produced by structural conversion o... more Infectious prions comprising abnormal prion protein, which is produced by structural conversion of normal prion protein, are responsible for transmissible spongiform encephalopathies including Creutzfeldt-Jakob disease in humans. Prions are infectious agents that do not possess a genome and the pathogenic protein was not thought to evoke any immune response. Although we previously reported that interferon regulatory factor 3 (IRF3) was likely to be involved in the pathogenesis of prion diseases, suggesting the protective role of host innate immune responses mediated by IRF3 signalling, this remained to be clarified. Here, we investigated the reciprocal interactions of type I interferon evoked by IRF3 activation and prion infection and found that infecting prions cause the suppression of endogenous interferon expression. Conversely, treatment with recombinant interferons in an ex vivo model was able to inhibit prion infection. In addition, cells and mice deficient in type I interferon receptor (subunit interferon alpha/beta receptor 1), exhibited higher susceptibility to 22L-prion infection. Moreover, in in vivo and ex vivo prion-infected models, treatment with RO8191, a selective type I interferon receptor agonist, inhibited prion invasion and prolonged the survival period of infected mice. Taken together, these data indicated that the interferon signalling interferes with prion propagation and some interferon-stimulated genes might play protective roles in the brain. These findings may allow for the development of new strategies to combat fatal diseases.
Social Science Research Network, 2021
Background: Neuropathology in sporadic Creutzfeldt–Jakob disease (sCJD) brains is usually investi... more Background: Neuropathology in sporadic Creutzfeldt–Jakob disease (sCJD) brains is usually investigated using formalin-fixed brains and formic acid-treated brains. However, brain tissues prepared in these ways are not amenable to biochemical analyses. We therefore developed RT-QuIC to quantitate the seeding activity (SD50) of sCJD brains. Methods: We used endpoint RT-QuIC assays to analyse SD50 in formalin-fixed brain tissue from 19 sCJD patients (14 MM1 cases, 3 MM2T cases and 2 MM2C cases) according to Parchi’s classification. We estimated SD50 in brains after incubation in formalin solution for over 1 month, and checked SD50 after treating formalin-fixed brain samples with formic acid. We also compared the neuropathological findings with SD50 from formalin-fixed brain samples from MM1, MM2T, and MM2C patients. Findings: RT-QuIC enables the study of formalin-fixed brains in sCJD patients that have not previously been amenable to analysis. Interpretation: The SD50 values of formalin...
Viruses, 2020
The emergence of resistance to currently available anti-influenza drugs has heightened the need f... more The emergence of resistance to currently available anti-influenza drugs has heightened the need for antivirals with novel mechanisms of action. The influenza A virus (IAV) nucleoprotein (NP) is highly conserved and essential for the formation of viral ribonucleoprotein (vRNP), which serves as the template for replication and transcription. Recently, using in silico screening, we identified an antiviral compound designated NUD-1 (a 4-hydroxyquinolinone derivative) as a potential inhibitor of NP. In this study, we further analyzed the interaction between NUD-1 and NP and found that the compound interferes with the oligomerization of NP, which is required for vRNP formation, leading to the suppression of viral transcription, protein synthesis, and nuclear export of NP. We further assessed the selection of resistant variants by serially passaging a clinical isolate of the 2009 H1N1 pandemic influenza virus in the presence of NUD-1 or oseltamivir. NUD-1 did not select for resistant varia...
Prion diseases are characterized by accumulation of amyloid fibrils. The causative agent is an in... more Prion diseases are characterized by accumulation of amyloid fibrils. The causative agent is an infectious amyloid that is comprised solely of misfolded prion protein (PrPSc). Prions can convert PrPC to proteinase-resistant PrP (PrP-res) in vitro; however, the intermediate steps involved in the spontaneous conversion remain unknown. We investigated whether recombinant prion protein (rPrP) can directly convert into PrP-res via liquid-liquid phase separation in the absence of PrPSc. We found that rPrP underwent liquid-liquid phase separation at the interface of the aqueous two-phase system (ATPS) of polyethylene glycol (PEG) and dextran, whereas single-phase conditions were not inducible. Fluorescence recovery assay after photobleaching revealed that the liquid-solid phase transition occurred within a short time. The aged rPrP-gel acquired proteinase-resistant amyloid accompanied by β-sheet conversion, as confirmed by western blotting, Fourier transform infrared spectroscopy, and Congo...
ACS Infectious Diseases, 2019
Abstrak --Penanaman nilai-nilai bela negara sangat diperlukan pada kalangan mahasiswa karena kere... more Abstrak --Penanaman nilai-nilai bela negara sangat diperlukan pada kalangan mahasiswa karena kerentanan dalam terpapar paham radikalisme, paham-paham radikalisme dengan mudah dapat memasuki mahasiswa karena kampus sebagai salah satu mimbar akademik dengan berbagai macam ideologi dapat masuk di dalam kampus. Dengan kerentanan ini sangat dibutuhkan peran sesama mahasiswa untuk melakukan upaya kontra radikal di kalangan mahasiswa. Adapun tujuan dari penelitian ini adalah melihat upaya kontra radikal dengan penginternalisasi nilai-nilai bela negara sebagai pada organisasi pergerakan mahasiswa yakni Kesatuan Aksi Mahasiswa Muslim Indonesia (KAMMI) Jakarta. Teori yang digunakan pada penelitian ini adalah teori strategi, teori internalisasi, konsep bela negara dan konsep kontra radikal. Metode penelitian yang digunakan adalah metode kualitatif dengan pendekatan studi kasus, teknik pengumpulan data dengan studi pustaka, studi dokumen, wawancara mendalam, dan observasi. Dalam pemeriksaan keabsahan data menggunakan metode triangulasi sumber, keikutsertaan peneliti, ketekunan dan keajegan pengamatan serta diskusi teman sejawat. Terdapat 5 strategi dalam internalisasi nilai-nilai bela negara pada organisasi KAMMI yakni melaksanakan sosialisasi syiar kebhinekaan, dalam setiap kegiatan menonjolkan nilai-nilai ke-Indonesiaan, mengadakan kegiatan kebangsaan, menggunakan tagline dan logo cirri khas Indonesia dan mengadakan diskusi serta FGD. Dalam upaya kontra radikal yang dilakukan oleh organisasi KAMMI adalah melalui dua cara yakni internal dan eksternal, untuk internal melalui proses pola pengkaderan, FGD rutin semingu sekali, mengadakan seminar atau diskusi yang bekerjasama dengan tokoh masyarakat dan tokoh agama. Dari eksternal mengadakan Deklarasi anti HOAX, mempublikasikan kegiatan dai KAMMI. Strategi internalisasi nilai-nilai bela negara dapat dilaksanakan dengan sumber daya manusia yang solid serta jaringan yang luas yang dimiliki oleh organisasi KAMMI. Nilai-nilai bela negara yang diinternalisasi baru empat nilai yang dapat diinternalisasi.
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Papers by Noriyuki Nishida