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1.
Int J Mol Sci ; 25(7)2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38612448

RESUMEN

The mechanisms of neuronal cell death in neurodegenerative disease remain incompletely understood, although recent studies have made significant advances. Apoptosis was previously considered to be the only mechanism of neuronal cell death in neurodegenerative diseases. However, recent findings have challenged this dogma, identifying new subtypes of necrotic neuronal cell death. The present review provides an updated summary of necrosis subtypes and discusses their potential roles in neurodegenerative cell death. Among numerous necrosis subtypes, including necroptosis, paraptosis, ferroptosis, and pyroptosis, transcriptional repression-induced atypical cell death (TRIAD) has been identified as a potential mechanism of neuronal cell death. TRIAD is induced by functional deficiency of TEAD-YAP and self-amplifies via the release of HMGB1. TRIAD is a feasible potential mechanism of neuronal cell death in Alzheimer's disease and other neurodegenerative diseases. In addition to induction of cell death, HMGB1 released during TRIAD activates brain inflammatory responses, which is a potential link between neurodegeneration and neuroinflammation.


Asunto(s)
Proteína HMGB1 , Enfermedades Neurodegenerativas , Humanos , Enfermedades Neuroinflamatorias , Necrosis , Muerte Celular
2.
Commun Biol ; 7(1): 413, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594382

RESUMEN

Better understanding of the earliest molecular pathologies of all neurodegenerative diseases is expected to improve human therapeutics. We investigated the earliest molecular pathology of spinocerebellar ataxia type 1 (SCA1), a rare familial neurodegenerative disease that primarily induces death and dysfunction of cerebellum Purkinje cells. Extensive prior studies have identified involvement of transcription or RNA-splicing factors in the molecular pathology of SCA1. However, the regulatory network of SCA1 pathology, especially central regulators of the earliest developmental stages and inflammatory events, remains incompletely understood. Here, we elucidated the earliest developmental pathology of SCA1 using originally developed dynamic molecular network analyses of sequentially acquired RNA-seq data during differentiation of SCA1 patient-derived induced pluripotent stem cells (iPSCs) to Purkinje cells. Dynamic molecular network analysis implicated histone genes and cytokine-relevant immune response genes at the earliest stages of development, and revealed relevance of ISG15 to the following degradation and accumulation of mutant ataxin-1 in Purkinje cells of SCA1 model mice and human patients.


Asunto(s)
Células Madre Pluripotentes Inducidas , Ataxias Espinocerebelosas , Animales , Humanos , Ratones , Citocinas , Células Madre Pluripotentes Inducidas/patología , Ratones Transgénicos , Células de Purkinje/fisiología , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/patología , Ubiquitinas
3.
Commun Med (Lond) ; 3(1): 170, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017287

RESUMEN

BACKGROUND: Charcot-Marie-Tooth disease type 1A (CMT1A) is one of the most common hereditary peripheral neuropathies caused by duplication of 1.5 Mb genome region including PMP22 gene. We aimed to correct the duplication in human CMT1A patient-derived iPS cells (CMT1A-iPSCs) by genome editing and intended to analyze the effect on Schwann cells differentiated from CMT1A-iPSCs. METHODS: We designed multiple gRNAs targeting a unique sequence present at two sites that sandwich only a single copy of duplicated peripheral myelin protein 22 (PMP22) genes, and selected one of them (gRNA3) from screening their efficiencies by T7E1 mismatch detection assay. AAV2-hSaCas9-gRNAedit was generated by subcloning gRNA3 into pX601-AAV-CMV plasmid, and the genome editing AAV vector was infected to CMT1A-iPSCs or CMT1A-iPSC-derived Schwann cell precursors. The effect of the genome editing AAV vector on myelination was evaluated by co-immunostaining of myelin basic protein (MBP), a marker of mature myelin, and microtubule-associated protein  2(MAP2), a marker of neurites or by electron microscopy. RESULTS: Here we show that infection of CMT1A-iPS cells (iPSCs) with AAV2-hSaCas9-gRNAedit expressing both hSaCas9 and gRNA targeting the tandem repeat sequence decreased PMP22 gene duplication by 20-40%. Infection of CMT1A-iPSC-derived Schwann cell precursors with AAV2-hSaCas9-gRNAedit normalized PMP22 mRNA and PMP22 protein expression levels, and also ameliorated increased apoptosis and impaired myelination in CMT1A-iPSC-derived Schwann cells. CONCLUSIONS: In vivo transfer of AAV2-hSaCas9-gRNAedit to peripheral nerves could be a potential therapeutic modality for CMT1A patient after careful examinations of toxicity including off-target mutations.


Charcot-Marie-Tooth disease type 1A (CMT1A) is a common heritable form of the condition that develops when nerves in the body's extremities, such as the hands, feet and arms, are damaged due to an extra copy of PMP22 gene being incorrectly produced. Currently, no known therapies exist. Here, we developed a method to delete the additional copy of PMP22 gene by 20­40% to prevent overproduction. Our results show that this method can reduce PMP22 protein production, leading to near normal production in patient's nerve cells. Further safety assessments should now be undertaken. If the treatment is safe for patients it could become a therapeutic option for CMT1A patients.

4.
Cell ; 186(22): 4898-4919.e25, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37827155

RESUMEN

Expansions of repeat DNA tracts cause >70 diseases, and ongoing expansions in brains exacerbate disease. During expansion mutations, single-stranded DNAs (ssDNAs) form slipped-DNAs. We find the ssDNA-binding complexes canonical replication protein A (RPA1, RPA2, and RPA3) and Alternative-RPA (RPA1, RPA3, and primate-specific RPA4) are upregulated in Huntington disease and spinocerebellar ataxia type 1 (SCA1) patient brains. Protein interactomes of RPA and Alt-RPA reveal unique and shared partners, including modifiers of CAG instability and disease presentation. RPA enhances in vitro melting, FAN1 excision, and repair of slipped-CAGs and protects against CAG expansions in human cells. RPA overexpression in SCA1 mouse brains ablates expansions, coincident with decreased ATXN1 aggregation, reduced brain DNA damage, improved neuron morphology, and rescued motor phenotypes. In contrast, Alt-RPA inhibits melting, FAN1 excision, and repair of slipped-CAGs and promotes CAG expansions. These findings suggest a functional interplay between the two RPAs where Alt-RPA may antagonistically offset RPA's suppression of disease-associated repeat expansions, which may extend to other DNA processes.


Asunto(s)
Proteína de Replicación A , Expansión de Repetición de Trinucleótido , Animales , Humanos , Ratones , ADN/genética , Reparación de la Incompatibilidad de ADN , Enfermedad de Huntington/genética , Proteínas/genética , Ataxias Espinocerebelosas/genética , Proteína de Replicación A/metabolismo
5.
Cell Rep ; 42(8): 112962, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37591248

RESUMEN

Prion-like protein propagation is considered a common pathogenic mechanism in neurodegenerative diseases. Here we investigate the in vivo propagation pattern and aggregation state of mutant α-synuclein by injecting adeno-associated viral (AAV)-α-synuclein-A53T-EGFP into the mouse olfactory cortex. Comparison of aggregation states in various brain regions at multiple time points after injection using western blot analyses shows that the monomeric state of the mutant/misfolded protein propagates to remote brain regions by 2 weeks and that the propagated proteins aggregate in situ after being incorporated into neurons. Moreover, injection of Alexa 488-labeled α-synuclein-A53T confirms the monomeric propagation at 2 weeks. Super-resolution microscopy shows that both α-synuclein-A53T proteins propagate via the lymphatic system, penetrate perineuronal nets, and reach the surface of neurons. Electron microscopy shows that the propagated mutant/misfolded monomer forms fibrils characteristic of Parkinson's disease after its incorporation into neurons. These findings suggest a mode of propagation different from that of aggregate-dependent propagation.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Animales , Ratones , alfa-Sinucleína/genética , Encéfalo , Sistema Linfático , Western Blotting , Proteínas Mutantes
6.
Nat Commun ; 14(1): 9, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36599853

RESUMEN

Polyglutamine binding protein 5 (PQBP5), also called nucleolar protein 10 (NOL10), binds to polyglutamine tract sequences and is expressed in the nucleolus. Using dynamic imaging of high-speed atomic force microscopy, we show that PQBP5/NOL10 is an intrinsically disordered protein. Super-resolution microscopy and correlative light and electron microscopy method show that PQBP5/NOL10 makes up the skeletal structure of the nucleolus, constituting the granule meshwork in the granular component area, which is distinct from other nucleolar substructures, such as the fibrillar center and dense fibrillar component. In contrast to other nucleolar proteins, which disperse to the nucleoplasm under osmotic stress conditions, PQBP5/NOL10 remains in the nucleolus and functions as an anchor for reassembly of other nucleolar proteins. Droplet and thermal shift assays show that the biophysical features of PQBP5/NOL10 remain stable under stress conditions, explaining the spatial role of this protein. PQBP5/NOL10 can be functionally depleted by sequestration with polyglutamine disease proteins in vitro and in vivo, leading to the pathological deformity or disappearance of the nucleolus. Taken together, these findings indicate that PQBP5/NOL10 is an essential protein needed to maintain the structure of the nucleolus.


Asunto(s)
Nucléolo Celular , Núcleo Celular , Proteínas Nucleares , Humanos , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Presión Osmótica/fisiología
7.
Commun Biol ; 5(1): 1404, 2022 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-36572749

RESUMEN

The recent whole-genome duplication (WGD) in goldfish (Carassius auratus) approximately 14 million years ago makes it a valuable model for studying gene evolution during the early stages after WGD. We analyzed the transcriptome of the goldfish retina at the level of single-cell (scRNA-seq) and open chromatin regions (scATAC-seq). We identified a group of genes that have undergone dosage selection, accounting for 5% of the total 11,444 ohnolog pairs. We also identified 306 putative sub/neo-functionalized ohnolog pairs that are likely to be under cell-type-specific genetic variation at single-cell resolution. Diversification in the expression patterns of several ohnolog pairs was observed in the retinal cell subpopulations. The single-cell level transcriptome analysis in this study uncovered the early stages of evolution in retinal cell of goldfish after WGD. Our results provide clues for understanding the relationship between the early stages of gene evolution after WGD and the evolution of diverse vertebrate retinal functions.


Asunto(s)
Carpa Dorada , Transcriptoma , Animales , Carpa Dorada/genética , Genoma , Evolución Molecular , Perfilación de la Expresión Génica
8.
Artículo en Inglés | MEDLINE | ID: mdl-36276857

RESUMEN

Kamishoyosan (KSS) is a traditional Japanese Kampo medicine that is prescribed for hormonal change-induced mood disorders including premenstrual syndrome (PMS). In clinical studies, KSS exhibited ameliorative effects on mood symptoms of PMS, such as anxiety and irritability. However, the mechanism underlying the beneficial effects of KSS is unclear. In the present study, we investigated the involvement of serotonergic machinery in the anxiolytic effects of KSS on hormonally-induced anxiety-like behavior in progesterone withdrawal (PWD) rats, which were used as a model of PMS. Female rats were injected with progesterone daily for 21 days. At 48 h after the final progesterone injection, anxiety-like behavior was evaluated using the elevated plus maze. KSS was administered orally to PWD rats 1 h prior to the test and significantly attenuated PWD-induced anxiety-like behavior. This ameliorative effect of KSS was reversed by WAY-100635, a serotonin (5-HT)1A receptor antagonist. The effect of KSS on serotonergic transmission in the prefrontal cortex of PWD rats was also evaluated using an in vivo microdialysis procedure. KSS significantly increased the extracellular 5-HT level in the prefrontal cortex of PWD rats. In conclusion, our results suggest that KSS alleviates PWD-induced anxiety-like behavior at least partly by activating 5-HT1A receptors and enhancing serotonergic transmission.

9.
Int J Mol Sci ; 23(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35682906

RESUMEN

The idea that a common pathology underlies various neurodegenerative diseases and dementias has attracted considerable attention in the basic and medical sciences. Polyglutamine binding protein-1 (PQBP1) was identified in 1998 after a molecule was predicted to bind to polyglutamine tract amino acid sequences, which are associated with a family of neurodegenerative disorders called polyglutamine diseases. Hereditary gene mutations of PQBP1 cause intellectual disability, whereas acquired loss of function of PQBP1 contributes to dementia pathology. PQBP1 functions in innate immune cells as an intracellular receptor that recognizes pathogens and neurodegenerative proteins. It is an intrinsically disordered protein that generates intracellular foci, similar to other neurodegenerative disease proteins such as TDP43, FUS, and hnRNPs. The knowledge accumulated over more than 20 years has given rise to a new concept that shifts in the equilibrium between physiological and pathological processes have their basis in the dysregulation of common protein structure-linked molecular mechanisms.


Asunto(s)
Discapacidad Intelectual , Enfermedades Neurodegenerativas , Proteínas Portadoras/metabolismo , Proteínas de Unión al ADN/metabolismo , Humanos , Inmunidad Innata , Discapacidad Intelectual/genética , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/metabolismo , Proteínas Nucleares/genética
10.
Cell Rep Med ; 3(4): 100597, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35492247

RESUMEN

From genetic and etiological studies, autoimmune mechanisms underlying schizophrenia are suspected; however, the details remain unclear. In this study, we describe autoantibodies against neural cell adhesion molecule (NCAM1) in patients with schizophrenia (5.4%, cell-based assay; 6.7%, ELISA) in a Japanese cohort (n = 223). Anti-NCAM1 autoantibody disrupts both NCAM1-NCAM1 and NCAM1-glial cell line-derived neurotrophic factor (GDNF) interactions. Furthermore, the anti-NCAM1 antibody purified from patients with schizophrenia interrupts NCAM1-Fyn interaction and inhibits phosphorylation of FAK, MEK1, and ERK1 when introduced into the cerebrospinal fluid of mice and also reduces the number of spines and synapses in frontal cortex. In addition, it induces schizophrenia-related behavior in mice, including deficient pre-pulse inhibition and cognitive impairment. In conclusion, anti-NCAM1 autoantibodies in patients with schizophrenia cause schizophrenia-related behavior and changes in synapses in mice. These antibodies may be a potential therapeutic target and serve as a biomarker to distinguish a small but treatable subgroup in heterogeneous patients with schizophrenia.


Asunto(s)
Moléculas de Adhesión de Célula Nerviosa , Esquizofrenia , Autoanticuerpos , Antígeno CD56/genética , Humanos , Moléculas de Adhesión de Célula Nerviosa/genética , Esquizofrenia/genética , Sinapsis/metabolismo
11.
Nat Commun ; 12(1): 6565, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34782623

RESUMEN

Brain inflammation generally accompanies and accelerates neurodegeneration. Here we report a microglial mechanism in which polyglutamine binding protein 1 (PQBP1) senses extrinsic tau 3R/4R proteins by direct interaction and triggers an innate immune response by activating a cyclic GMP-AMP synthase (cGAS)-Stimulator of interferon genes (STING) pathway. Tamoxifen-inducible and microglia-specific depletion of PQBP1 in primary culture in vitro and mouse brain in vivo shows that PQBP1 is essential for sensing-tau to induce nuclear translocation of nuclear factor κB (NFκB), NFκB-dependent transcription of inflammation genes, brain inflammation in vivo, and eventually mouse cognitive impairment. Collectively, PQBP1 is an intracellular receptor in the cGAS-STING pathway not only for cDNA of human immunodeficiency virus (HIV) but also for the transmissible neurodegenerative disease protein tau. This study characterises a mechanism of brain inflammation that is common to virus infection and neurodegenerative disorders.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Encefalitis/metabolismo , Proteínas de la Membrana/metabolismo , Microglía/metabolismo , Nucleotidiltransferasas/metabolismo , Animales , Encéfalo , Proteínas de Unión al ADN/genética , Encefalitis/inmunología , Femenino , VIH , Humanos , Inmunidad Innata , Masculino , Glicoproteínas de Membrana , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/efectos de los fármacos , FN-kappa B/metabolismo , Enfermedades Neurodegenerativas , Nucleotidiltransferasas/genética , Tamoxifeno/farmacología
12.
Commun Biol ; 4(1): 1175, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34635772

RESUMEN

DNA damage is increased in Alzheimer's disease (AD), while the underlying mechanisms are unknown. Here, we employ comprehensive phosphoproteome analysis, and identify abnormal phosphorylation of 70 kDa subunit of Ku antigen (Ku70) at Ser77/78, which prevents Ku70-DNA interaction, in human AD postmortem brains. The abnormal phosphorylation inhibits accumulation of Ku70 to the foci of DNA double strand break (DSB), impairs DNA damage repair and eventually causes transcriptional repression-induced atypical cell death (TRIAD). Cells under TRIAD necrosis reveal senescence phenotypes. Extracellular high mobility group box 1 (HMGB1) protein, which is released from necrotic or hyper-activated neurons in AD, binds to toll-like receptor 4 (TLR4) of neighboring neurons, and activates protein kinase C alpha (PKCα) that executes Ku70 phosphorylation at Ser77/78. Administration of human monoclonal anti-HMGB1 antibody to post-symptomatic AD model mice decreases neuronal DSBs, suppresses secondary TRIAD necrosis of neurons, prevents escalation of neurodegeneration, and ameliorates cognitive symptoms. TRIAD shares multiple features with senescence. These results discover the HMGB1-Ku70 axis that accounts for the increase of neuronal DNA damage and secondary enhancement of TRIAD, the cell death phenotype of senescence, in AD.


Asunto(s)
Enfermedad de Alzheimer/patología , Daño del ADN , Reparación del ADN , Proteína HMGB1/fisiología , Autoantígeno Ku/metabolismo , Transducción de Señal/genética , Animales , Proteína HMGB1/genética , Ratones , Ratones Transgénicos , Fosforilación
13.
Commun Biol ; 4(1): 961, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-34385591

RESUMEN

Multiple gene mutations cause familial frontotemporal lobar degeneration (FTLD) while no single gene mutations exists in sporadic FTLD. Various proteins aggregate in variable regions of the brain, leading to multiple pathological and clinical prototypes. The heterogeneity of FTLD could be one of the reasons preventing development of disease-modifying therapy. We newly develop a mathematical method to analyze chronological changes of PPI networks with sequential big data from comprehensive phosphoproteome of four FTLD knock-in (KI) mouse models (PGRNR504X-KI, TDP43N267S-KI, VCPT262A-KI and CHMP2BQ165X-KI mice) together with four transgenic mouse models of Alzheimer's disease (AD) and with APPKM670/671NL-KI mice at multiple time points. The new method reveals the common core pathological network across FTLD and AD, which is shared by mouse models and human postmortem brains. Based on the prediction, we performed therapeutic intervention of the FTLD models, and confirmed amelioration of pathologies and symptoms of four FTLD mouse models by interruption of the core molecule HMGB1, verifying the new mathematical method to predict dynamic molecular networks.


Asunto(s)
Enfermedad de Alzheimer/etiología , Modelos Animales de Enfermedad , Degeneración Lobar Frontotemporal/etiología , Enfermedad de Alzheimer/patología , Animales , Degeneración Lobar Frontotemporal/patología , Humanos , Ratones , Ratones Transgénicos , Modelos Teóricos
14.
ACS Chem Neurosci ; 12(16): 3015-3027, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34319089

RESUMEN

Tau aggregation is a central hallmark of tauopathies such as frontotemporal lobar degeneration and progressive supranuclear palsy as well as of Alzheimer's disease, and it has been a target for therapeutic development. Herein, we unexpectedly found that hepta-histidine (7H), an inhibitor of the interaction between Ku70 and Huntingtin proteins, suppresses aggregation of Tau-R3 peptides in vitro. Addition of the trans-activator of transcription (TAT) sequence (YGRKKRRQRRR) derived from the TAT protein to 7H increased its permeability into cells, and TAT-7H treatment of iPS cell-derived neurons carrying Tau or APP mutations suppressed Tau phosphorylation. These results indicate that 7H is a promising lead compound for developing anti-aggregation drugs against Tau-related neurodegenerative diseases including Alzheimer's disease (AD).


Asunto(s)
Enfermedad de Alzheimer , Degeneración Lobar Frontotemporal , Tauopatías , Enfermedad de Alzheimer/tratamiento farmacológico , Histidina , Humanos , Proteínas tau
15.
Life Sci Alliance ; 4(7)2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34130995

RESUMEN

The early-stage pathologies of frontotemporal lobal degeneration (FTLD) remain largely unknown. In VCPT262A-KI mice carrying VCP gene mutation linked to FTLD, insufficient DNA damage repair in neural stem/progenitor cells (NSCs) activated DNA-PK and CDK1 that disabled MCM3 essential for the G1/S cell cycle transition. Abnormal neural exit produced neurons carrying over unrepaired DNA damage and induced early-stage transcriptional repression-induced atypical cell death (TRIAD) necrosis accompanied by the specific markers pSer46-MARCKS and YAP. In utero gene therapy expressing normal VCP or non-phosphorylated mutant MCM3 rescued DNA damage, neuronal necrosis, cognitive function, and TDP43 aggregation in adult neurons of VCPT262A-KI mice, whereas similar therapy in adulthood was less effective. The similar early-stage neuronal necrosis was detected in PGRNR504X-KI, CHMP2BQ165X-KI, and TDPN267S-KI mice, and blocked by embryonic treatment with AAV-non-phospho-MCM3. Moreover, YAP-dependent necrosis occurred in neurons of human FTLD patients, and consistently pSer46-MARCKS was increased in cerebrospinal fluid (CSF) and serum of these patients. Collectively, developmental stress followed by early-stage neuronal necrosis is a potential target for therapeutics and one of the earliest general biomarkers for FTLD.


Asunto(s)
Degeneración Lobar Frontotemporal/patología , Células-Madre Neurales/metabolismo , Proteína que Contiene Valosina/metabolismo , Animales , Ciclo Celular , Linaje de la Célula/genética , Células Cultivadas , Daño del ADN/genética , Daño del ADN/fisiología , Proteínas de Unión al ADN/metabolismo , Degeneración Lobar Frontotemporal/líquido cefalorraquídeo , Degeneración Lobar Frontotemporal/genética , Expresión Génica/genética , Regulación de la Expresión Génica/genética , Ratones , Ratones Endogámicos C57BL , Mutación , Necrosis/metabolismo , Necrosis/patología , Células-Madre Neurales/patología , Neuronas/metabolismo , Proteína que Contiene Valosina/genética
16.
J Biol Chem ; 297(1): 100873, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34126070

RESUMEN

Macroautophagy dysregulation is implicated in multiple neurological disorders, such as Parkinson's disease. While autophagy pathways are heavily researched in heterologous cells and neurons, regulation of autophagy in the astrocyte, the most abundant cell type in the mammalian brain, is less well understood. Missense mutations in the Synj1 gene encoding Synaptojanin1 (Synj1), a neuron-enriched lipid phosphatase, have been linked to Parkinsonism with seizures. Our previous study showed that the Synj1 haploinsufficient (Synj1+/-) mouse exhibits age-dependent autophagy impairment in multiple brain regions. Here, we used cultured astrocytes from Synj1-deficient mice to investigate its role in astrocyte autophagy. We report that Synj1 is expressed in low levels in astrocytes and represses basal autophagosome formation. We demonstrate using cellular imaging that Synj1-deficient astrocytes exhibit hyperactive autophagosome formation, represented by an increase in the size and number of GFP-microtubule-associated protein 1A/1B-light chain 3 structures. Interestingly, Synj1 deficiency is also associated with an impairment in stress-induced autophagy clearance. We show, for the first time, that the Parkinsonism-associated R839C mutation impacts autophagy in astrocytes. The impact of this mutation on the phosphatase function of Synj1 resulted in elevated basal autophagosome formation that mimics Synj1 deletion. We found that the membrane expression of the astrocyte-specific glucose transporter GluT-1 was reduced in Synj1-deficient astrocytes. Consistently, AMP-activated protein kinase activity was elevated, suggesting altered glucose sensing in Synj1-deficient astrocytes. Expressing exogenous GluT-1 in Synj1-deficient astrocytes reversed the autophagy impairment, supporting a role for Synj1 in regulating astrocyte autophagy via disrupting glucose-sensing pathways. Thus, our work suggests a novel mechanism for Synj1-related Parkinsonism involving astrocyte dysfunction.


Asunto(s)
Astrocitos/metabolismo , Autofagosomas/metabolismo , Proteínas del Tejido Nervioso/genética , Enfermedad de Parkinson/genética , Monoéster Fosfórico Hidrolasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Autofagia , Células Cultivadas , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Mutación Missense , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/metabolismo , Monoéster Fosfórico Hidrolasas/deficiencia , Monoéster Fosfórico Hidrolasas/metabolismo , Proteínas Quinasas/metabolismo , Regulación hacia Arriba
17.
Sci Rep ; 11(1): 3004, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33542264

RESUMEN

The aim of this study is to evaluate the relationship between retinal structures and visual acuity in diabetic patients using optical coherence tomography (OCT) and OCT angiography (OCTA). This study was a retrospective observational study conducted at a single medical center in Japan. Evaluation of retinal images was analyzed using spectral domain OCT. Twelve factors including central retinal thickness, length of disorganization of retinal inner layer (DRIL), number of inner hyperreflective foci, number of outer hyperreflective foci, height of intraretinal fluid, height of subretinal fluid, length of external limiting membrane disruption, length of external ellipsoid zone (EZ) disruption, vessel density of superficial capillary plexus (SCP), foveal avascular zone (FAZ) area, and FAZ circularity were analyzed based on OCT/OCTA findings. Multivariate analysis was used to investigate the OCT-based factors that could be correlated with poor visual acuity in treatment-naïve diabetic eyes. A total of 183 eyes of 123 diabetic patients with type 2 diabetes (mean age 61.9 ± 12.3 years, 66 men and 57 women) and 62 eyes of 55 control subjects (mean age 64.4 ± 12.5 years, 15 men and 40 women) was enrolled in this study. Multiple regression analysis showed that OCT-based factors correlated with visual acuity were length of DRIL (ß = 0.24, P < 0.01), length of EZ disruption (ß = 0.35, P < 0.001), and FAZ circularity (ß = - 0.14, P < 0.05). The other factors showed no significant correlation. In conclusion, the length of DRIL, length of EZ disruption, and FAZ circularity measured by OCT were identified as related factors for visual impairment in treatment-naïve diabetic eyes.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico por imagen , Retinopatía Diabética/diagnóstico , Edema Macular/diagnóstico por imagen , Trastornos de la Visión/diagnóstico por imagen , Adulto , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patología , Retinopatía Diabética/diagnóstico por imagen , Retinopatía Diabética/etiología , Retinopatía Diabética/patología , Femenino , Angiografía con Fluoresceína , Humanos , Mácula Lútea/diagnóstico por imagen , Mácula Lútea/patología , Edema Macular/diagnóstico , Edema Macular/patología , Masculino , Persona de Mediana Edad , Retina/diagnóstico por imagen , Retina/patología , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Tomografía de Coherencia Óptica , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología , Agudeza Visual/fisiología
18.
Nat Commun ; 11(1): 507, 2020 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-31980612

RESUMEN

The timing and characteristics of neuronal death in Alzheimer's disease (AD) remain largely unknown. Here we examine AD mouse models with an original marker, myristoylated alanine-rich C-kinase substrate phosphorylated at serine 46 (pSer46-MARCKS), and reveal an increase of neuronal necrosis during pre-symptomatic phase and a subsequent decrease during symptomatic phase. Postmortem brains of mild cognitive impairment (MCI) rather than symptomatic AD patients reveal a remarkable increase of necrosis. In vivo imaging reveals instability of endoplasmic reticulum (ER) in mouse AD models and genome-edited human AD iPS cell-derived neurons. The level of nuclear Yes-associated protein (YAP) is remarkably decreased in such neurons under AD pathology due to the sequestration into cytoplasmic amyloid beta (Aß) aggregates, supporting the feature of YAP-dependent necrosis. Suppression of early-stage neuronal death by AAV-YAPdeltaC reduces the later-stage extracellular Aß burden and cognitive impairment, suggesting that preclinical/prodromal YAP-dependent neuronal necrosis represents a target for AD therapeutics.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Proteínas de Ciclo Celular/metabolismo , Factores de Transcripción/metabolismo , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Animales , Núcleo Celular/metabolismo , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/patología , Simulación por Computador , Modelos Animales de Enfermedad , Retículo Endoplásmico/patología , Retículo Endoplásmico/ultraestructura , Femenino , Proteína HMGB1/líquido cefalorraquídeo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Lisofosfolípidos/metabolismo , Masculino , Ratones Transgénicos , Necrosis , Neuronas/metabolismo , Neuronas/patología , Transducción de Señal , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Imagen de Lapso de Tiempo , Proteínas Señalizadoras YAP
19.
Mol Psychiatry ; 23(10): 2090-2110, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30283027

RESUMEN

Early-phase pathologies of Alzheimer's disease (AD) are attracting much attention after clinical trials of drugs designed to remove beta-amyloid (Aß) aggregates failed to recover memory and cognitive function in symptomatic AD patients. Here, we show that phosphorylation of serine/arginine repetitive matrix 2 (SRRM2) at Ser1068, which is observed in the brains of early phase AD mouse models and postmortem end-stage AD patients, prevents its nuclear translocation by inhibiting interaction with T-complex protein subunit α. SRRM2 deficiency in neurons destabilized polyglutamine binding protein 1 (PQBP1), a causative gene for intellectual disability (ID), greatly affecting the splicing patterns of synapse-related genes, as demonstrated in a newly generated PQBP1-conditional knockout model. PQBP1 and SRRM2 were downregulated in cortical neurons of human AD patients and mouse AD models, and the AAV-PQBP1 vector recovered RNA splicing, the synapse phenotype, and the cognitive decline in the two mouse models. Finally, the kinases responsible for the phosphorylation of SRRM2 at Ser1068 were identified as ERK1/2 (MAPK3/1). These results collectively reveal a new aspect of AD pathology in which a phosphorylation signal affecting RNA splicing and synapse integrity precedes the formation of extracellular Aß aggregates and may progress in parallel with tau phosphorylation.


Asunto(s)
Enfermedad de Alzheimer/genética , Proteínas Portadoras/genética , Proteínas Nucleares/genética , Proteínas de Unión al ARN/genética , Transporte Activo de Núcleo Celular , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Encéfalo/metabolismo , Proteínas Portadoras/metabolismo , Cognición , Proteínas de Unión al ADN , Modelos Animales de Enfermedad , Humanos , Células Madre Pluripotentes Inducidas , Discapacidad Intelectual/genética , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neuronas/metabolismo , Proteínas Nucleares/metabolismo , Fosforilación , Cultivo Primario de Células , Empalme del ARN , Proteínas de Unión al ARN/metabolismo , Proteínas tau/metabolismo
20.
Bioorg Med Chem Lett ; 27(5): 1169-1174, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28169168

RESUMEN

Human glyoxalase I (GLO I), a rate-limiting enzyme for detoxification of methylglyoxal (MG), a by-product of glycolysis, is known to be a potential therapeutic target for cancer. Here, we searched new scaffolds from natural compounds for designing novel GLO I inhibitors and found trans-stilbene scaffold. We examined the inhibitory abilities to human GLO I of commercially available trans-stilbene compounds. Among them, piceatannol was found to have the most potent inhibitory activity against human GLO I. Piceatannol could inhibit the proliferation of human lung cancer NCI-H522 cells, which are dependent on GLO I for survival, in a dose- and time-dependent manner. In addition, piceatannol more significantly inhibited the proliferation of NCI-H522 cells than that of NCI-H460 cells, which are less dependent on GLO I. Importantly, overexpression of GLO I in NCI-H522 cells resulted in less sensitive to the antiproliferative activity of piceatannol. Taken together, this is the first report demonstrating that piceatannol inhibits GLO I activity and the GLO I-dependent proliferation of cancer cells. Furthermore, we determined a pharmacophore for novel inhibitors of human GLO I by computational simulation analyses of the binding mode of piceatannol to the enzyme hot spot in the active site. We suggest that piceatannol is a possible lead compound for the development of novel GLO I inhibitory anticancer drugs.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Lactoilglutatión Liasa/antagonistas & inhibidores , Estilbenos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/patología
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