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2.
Acta Neuropathol ; 145(5): 573-595, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939875

RESUMO

Lipid interaction with α-synuclein (αSyn) has been long implicated in the pathogenesis of Parkinson's disease (PD). However, it has not been fully determined which lipids are involved in the initiation of αSyn aggregation in PD. Here exploiting genetic understanding associating the loss-of-function mutation in Synaptojanin 1 (SYNJ1), a phosphoinositide phosphatase, with familial PD and analysis of postmortem PD brains, we identified a novel lipid molecule involved in the toxic conversion of αSyn and its relation to PD. We first established a SYNJ1 knockout cell model and found SYNJ1 depletion increases the accumulation of pathological αSyn. Lipidomic analysis revealed SYNJ1 depletion elevates the level of its substrate phosphatidylinositol-3,4,5-trisphosphate (PIP3). We then employed Caenorhabditis elegans model to examine the effect of SYNJ1 defect on the neurotoxicity of αSyn. Mutations in SYNJ1 accelerated the accumulation of αSyn aggregation and induced locomotory defects in the nematodes. These results indicate that functional loss of SYNJ1 promotes the pathological aggregation of αSyn via the dysregulation of its substrate PIP3, leading to the aggravation of αSyn-mediated neurodegeneration. Treatment of cultured cell line and primary neurons with PIP3 itself or with PIP3 phosphatase inhibitor resulted in intracellular formation of αSyn inclusions. Indeed, in vitro protein-lipid overlay assay validated that phosphoinositides, especially PIP3, strongly interact with αSyn. Furthermore, the aggregation assay revealed that PIP3 not only accelerates the fibrillation of αSyn, but also induces the formation of fibrils sharing conformational and biochemical characteristics similar to the fibrils amplified from the brains of PD patients. Notably, the immunohistochemical and lipidomic analyses on postmortem brain of patients with sporadic PD showed increased PIP3 level and its colocalization with αSyn. Taken together, PIP3 dysregulation promotes the pathological aggregation of αSyn and increases the risk of developing PD, and PIP3 represents a potent target for intervention in PD.


Assuntos
Doença de Parkinson , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Encéfalo/patologia , Lipídeos , Neurônios/patologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo
3.
Front Med (Lausanne) ; 9: 708188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355603

RESUMO

Purpose: To evaluate hyperopia-correcting phototherapeutic keratectomy (HC-PTK) and to compare the visual and refractive outcomes of HC-PTK and conventional PTK. Methods: This study comprised a total of 72 eyes of 72 consecutive patients who underwent HC-PTK and conventional PTK for granular corneal dystrophy or band-shaped keratopathy. Preoperatively and 6 months postoperatively, we assessed visual acuity, manifest refraction, and mean keratometry, as well as postoperative corneal higher-order aberrations and adverse events in each PTK group, and compared these metrics between the two groups. Results: LogMAR BSCVA significantly improved from 0.43 ± 0.47 preoperatively to 0.21 ± 0.38 postoperatively in the HC-PTK group (Wilcoxon signed-rank test, p < 0.001). It was also significantly improved from 0.22 ± 0.21 preoperatively to 0.15 ± 0.12 postoperatively in the conventional PTK group (p = 0.031). Mean refraction significantly changed from 0.27 ± 1.55 diopter (D) preoperatively to 0.50 ± 1.77 D postoperatively, in the HC-PTK group (p = 0.313). By contrast, it was significantly hyperopic from -0.15 ± 2.41 D preoperatively to 1.45 ± 2.46 D postoperatively, in the conventional PTK group (p < 0.001). No significant complications occurred in any case during the follow-up period. Conclusion: Both HC-PTK and conventional PTK showed a significant improvement of BSCVA and no vision-threatening complications at any time in this series. HC-PTK significantly reduced a hyperopic shift in refraction compared with conventional PTK, suggesting its viability for patients requiring PTK, especially in consideration of preventing this hyperopic issue.

4.
PLoS One ; 17(2): e0263506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35134078

RESUMO

Aspherical- and multi-curve rigid gas-permeable hard contact lenses (HCLs) have a flattened curve in the peripheral zone and are mostly used for patients with keratoconus who cannot wear glasses, soft contact lenses, or spherical HCLs. In this retrospective study, a total of 95 eyes of 77 patients who used aspherical- or multi-curve HCLs (mean age: 40.0 ± 11.0 years) were evaluated. This study examined the types of aspherical- and multi-curve HCLs, best-corrected visual acuity (BCVA) values before and after wearing HCLs, the association with the Amsler-Krumeich classification, duration of wear, corneal/conjunctival disorder, and the frequency of changing HCLs. There were 78 eyes that used aspherical-curve HCLs and 17 that used multi-curve HCLs. BCVA significantly improved from 0.42 logMAR to 0.06 logMAR after wearing either form of HCL. The Amsler-Krumeich classification showed that aspherical-curve HCLs were commonly used for patients with stage 2 keratoconus, and multi-curve HCLs were commonly used for stage 4 patients. The BCVA values were worse when the disease stage was more severe (stages 3 and 4) regardless of HCL type. The mean base curve of the lenses was steeper in multi-curve HCLs than in aspherical-curve HCLs. The more severe the disease stage, the steeper the base curve in both aspherical- and multi-curve HCLs. The duration of wear significantly improved from 2.1 h to 10.2 h, and corneal/conjunctival disorder similarly improved. The mean frequency of changing HCL types was 1.1 times. This study suggests that a flat peripheral curve design with aspherical- and multi-curve HCLs is useful for patients with keratoconus.


Assuntos
Lentes de Contato/tendências , Ceratocone/terapia , Adulto , Córnea/fisiologia , Topografia da Córnea/métodos , Feminino , Humanos , Ceratocone/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acuidade Visual/fisiologia
5.
Ophthalmol Ther ; 11(2): 701-710, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35119584

RESUMO

INTRODUCTION: To assess the 1-year outcomes of vertically fixated posterior chamber phakic intraocular lens implantation through a superior corneal incision. METHODS: This pilot study comprised 78 eyes of 53 consecutive patients undergoing vertically fixated implantable collamer lens (ICL) implantation through a superior corneal incision to correct moderate to high myopia and myopic astigmatism. We prospectively determined the safety, efficacy, predictability, stability, and adverse events preoperatively, and at 1 week and 1, 3, and 12 months postoperatively. RESULTS: The mean follow-up period was 10.4 ± 5.4 months. Uncorrected and corrected visual acuity were -0.20 ± 0.10 and -0.25 ± 0.07 logMAR, respectively, at 1 year postoperatively. At 1 year postoperatively, 98% and 100% of eyes were within 0.5 and 1.0 D, respectively, of the targeted correction. A nonsignificant change in manifest refraction of -0.01 ± 0.08 D occurred from 1 week to 1 year. The manifest astigmatism decreased significantly, from 0.69 ± 0.73 D preoperatively to 0.21 ± 0.27 D at 1 year postoperatively (Mann-Whitney U test, p < 0.001). No vision-threatening complications occurred at any time in this series. CONCLUSIONS: According to our experience, the vertically fixated ICL through a superior incision achieved good results, without significant complications. Considering that younger patients requiring ICL surgery tend to have with-the-rule astigmatism, this surgical technique may be a viable option for reducing astigmatism without using toric ICLs.

6.
Front Med (Lausanne) ; 8: 799078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34977099

RESUMO

Purpose: To assess the 8-year clinical outcomes of implantation of an implantable collamer lens (ICL) with a central port (KS-Aquaport; EVO-ICL) for moderate to high myopia and myopic astigmatism. Methods: This retrospective study comprised a total of 177 eyes of 106 patients with spherical equivalents of -7.99 ± 3.33 D [mean ± standard deviation], who underwent EVO-ICL implantation. We evaluated the safety, efficacy, predictability, stability, and adverse events of the surgery, at 1 month, and 1, 2, 4, 6, and 8 years postoperatively. Results: The logarithm of the minimal angle of resolution (LogMAR) uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were -0.07 ± 0.17 and -0.20 ± 0.09, respectively, at 8 years postoperatively. The safety and efficacy indices were 1.18 ± 0.24 and 0.89 ± 0.28, respectively. At 8 years, 83 and 93% eyes were within ± 0.5 D and ± 1.0 D of the targeted correction, respectively. Change in manifest refraction from 1 month to 8 years postoperatively was -0.13 ± 0.30 D. Three eyes (1.7%) that developed cataracts had a slight pre-existing peripheral anterior subcapsular cataract formation required simultaneous ICL extraction and cataract surgery at 2 or 3 years or ICL size change (1 size up) at 7 years postoperatively. We found that neither significant intraocular pressure (IOP) rise (including pupillary block) nor significant endothelial cell loss occurred in any case throughout the 8-year observation period. Conclusions: Current ICL implantation with central port technology offered good continuous outcomes for all measures of safety, efficacy, predictability, and stability for correcting moderate to high myopic errors over a long period, thereby suggesting its long-term viability as a surgical approach for the treatment of such eyes.

7.
Autophagy ; 17(10): 2962-2974, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33218272

RESUMO

Mitochondrial quality control, which is crucial for maintaining cellular homeostasis, has been considered to be achieved exclusively through mitophagy. Here we report an alternative mitochondrial quality control pathway mediated by extracellular mitochondria release. By performing time-lapse confocal imaging on a stable cell line with fluorescent-labeled mitochondria, we observed release of mitochondria from cells into the extracellular space. Correlative light-electron microscopy revealed that majority of the extracellular mitochondria are in free form and, on rare occasions, some are enclosed in membrane-surrounded vesicles. Rotenone- and carbonyl cyanide m-chlorophenylhydrazone-induced mitochondrial quality impairment promotes the extracellular release of depolarized mitochondria. Overexpression of PRKN (parkin RBR E3 ubiquitin protein ligase), which has a pivotal role in mitophagy regulation, suppresses the extracellular mitochondria release under basal and stress condition, whereas its knockdown exacerbates it. Correspondingly, overexpression of PRKN-independent mitophagy regulators, BNIP3 (BCL2 interacting protein 3) and BNIP3L/NIX (BCL2 interacting protein 3 like), suppress extracellular mitochondria release. Autophagy-deficient cell lines show elevated extracellular mitochondria release. These results imply that perturbation of mitophagy pathway prompts mitochondria expulsion. Presence of mitochondrial protein can also be detected in mouse sera. Sera of PRKN-deficient mice contain higher level of mitochondrial protein compared to that of wild-type mice. More importantly, fibroblasts and cerebrospinal fluid samples from Parkinson disease patients carrying loss-of-function PRKN mutations show increased extracellular mitochondria compared to control subjects, providing evidence in a clinical context. Taken together, our findings suggest that extracellular mitochondria release is a comparable yet distinct quality control pathway from conventional mitophagy.Abbreviations: ACTB: actin beta; ANXA5: annexin A5; ATP5F1A/ATP5A: ATP synthase F1 subunit alpha; ATG: autophagy related; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; CCCP: carbonyl cyanide m-chlorophenylhydrazone; CM: conditioned media; CSF: cerebrospinal fluid; DMSO: dimethyl sulfoxide; EM: electron microscopy; HSPD1/Hsp60: heat shock protein family D (Hsp60) member 1; KD: knockdown; KO: knockout; MAP1LC3A/LC3: microtubule associated protein 1 light chain 3 alpha; MT-CO1: mitochondrially encoded cytochrome c oxidase I; NDUFB8: NADH:ubiquinone oxidoreductase subunit B8; OE: overexpression; OPA1: OPA1 mitochondrial dynamin like GTPase; OXPHOS: oxidative phosphorylation; PBS: phosphate-buffered saline; PB: phosphate buffer; PD: Parkinson disease; PINK1: PTEN induced kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; RB1CC1/FIP200: RB1 inducible coiled-coil 1; SDHB: succinate dehydrogenase complex iron sulfur subunit B; TOMM20: translocase of outer mitochondrial membrane 20; TOMM40: translocase of outer mitochondrial membrane 40; UQCRC2: ubiquinol-cytochrome c reductase core protein 2; WT: wild-type.


Assuntos
Autofagia , Mitofagia , Animais , Autofagia/fisiologia , Humanos , Camundongos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/genética , Ubiquitina-Proteína Ligases/metabolismo
8.
Neurotherapeutics ; 18(1): 460-473, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33083995

RESUMO

Go-sha-jinki-Gan (GJG) is a traditional Japanese herbal medicine. In clinical practice, GJG is effective against neuropathic pain and hypersensitivity induced by chemotherapy or diabetes. In our previous study using a chronic constriction injury mouse model, we showed that GJG inhibited microglia activation by suppressing the expression of tumor necrosis factor-α (TNF-α) and p38 mitogen-activated protein kinase (p38 MAPK) in the peripheral nervous system. To investigate whether GJG can suppress inflammation in the central nervous system (CNS) in the context of neurological disorders, we examined the effect of GJG on the activation of resident glial cells and on p38-TNF signaling in two mouse models of neurological disorders: the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinson's disease. GJG administration relieved the severity of clinical EAE symptoms and MPTP-induced inflammation by decreasing the number of microglia and the production of TNF-α in the spinal cord of EAE mice and the substantia nigra of MPTP-treated mice. Accordingly, GJG suppressed the phosphorylation of p38 in glial cells of these two mouse models. We conclude that GJG attenuates inflammation of the CNS by suppressing glial cell activation, followed by a decrease in the production of TNF-α via p38-TNF signaling.


Assuntos
Sistema Nervoso Central/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Transtornos Parkinsonianos/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Sistema Nervoso Central/efeitos dos fármacos , Feminino , Medicina Herbária/métodos , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
9.
Sci Rep ; 10(1): 21686, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303807

RESUMO

This study was aimed to review the etiology and the outcomes of current posterior chamber phakic intraocular lens (Visian ICL, STAAR Surgical) extraction. This review comprised 770 eyes of 403 consecutive patients undergoing ICL extraction. We evaluated prevalence, etiology, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), predictability, and patient satisfaction. ICL extraction was required in 8 of 770 (1.0%) eyes. The most common reason was the progression of the pre-existing cataract formation in 5 eyes (63%), followed by residual refractive errors in 3 eyes (38%). Of the 7 eyes targeted for emmetropia, 7 (100%) and 6 (86%) achieved UDVAs of 20/40 and 20/20 or better, respectively. Three eyes (38%) showed no change in CDVA, 3 eyes (38%) gained 1 line, 2 eyes (25%) gained 3 or more lines. 88% and 100% were within ± 0.5 and 1.0 diopter (D), respectively, of the targeted correction. Patient satisfaction improved significantly, from 3.0 ± 1.4 preoperatively, to 8.0 ± 2.4 postoperatively. No vision-threatening complications occurred. ICL extraction was required in approximately 1% of ICL-implanted eyes. Visual and refractive outcomes were good, and patient satisfaction was overall high, even in ICL-extracted eyes.


Assuntos
Astigmatismo/cirurgia , Catarata/etiologia , Remoção de Dispositivo/métodos , Implante de Lente Intraocular/métodos , Miopia/cirurgia , Satisfação do Paciente , Lentes Intraoculares Fácicas/efeitos adversos , Adulto , Astigmatismo/fisiopatologia , Progressão da Doença , Feminino , Humanos , Implante de Lente Intraocular/efeitos adversos , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Erros de Refração/etiologia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual
10.
J Clin Med ; 9(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352917

RESUMO

This study aimed to compare the achieved vault using a manufacturer's nomogram and the predicted vault using the currently available prediction formulas after posterior chamber phakic intraocular lens (EVO Implantable Collamer Lens; ICL, STAAR Surgical) implantation. We included 200 eyes of 100 consecutive patients (mean age ± standard deviation, 34.3 ± 7.8 years) undergoing ICL implantation with a central hole. Three months postoperatively, we quantitatively measured the actual vault, and we compared it with the predicted vault using anterior segment optical coherence tomography (CASIA 2, Tomey). The agreement rate of the recommended ICL size using the manufacturer's nomogram, the NK formula, and the KS formula was 50.0%. The achieved vault was 477.1 ± 263.7 µm, which was significantly smaller than the predicted vaults of 551.2 ± 335.1 and 606.4 ± 212.2 µm, using the NK and KS formulas, respectively (Dunnett test, p = 0.014, p < 0.001). The achieved vault was not significantly different from the predicted vault using the NK or KS formula (p = 0.386, p = 0.157) when selecting a 12.1 mm ICL size. It was not significantly different from the predicted vault using the NK formula (p = 0.962), but it was significantly smaller than that using the KS formula (p = 0.033) when selecting a 12.6 mm size. It was significantly smaller than the predicted vault using the NK and KS formulas (p < 0.001) when selecting 13.2 mm size. The total agreement rate of the recommended ICL size was approximately 50%. The predicted ICL vault tended to overestimate the actual ICL vault, especially when selecting a larger ICL size.

11.
Sci Rep ; 10(1): 19423, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173082

RESUMO

Lewy bodies (LBs) and glial cytoplasmic inclusions (GCIs) are specific aggregates found in Parkinson's disease (PD) and multiple system atrophy (MSA), respectively. These aggregates mainly consist of α-synuclein (α-syn) and have been reported to propagate in the brain. In animal experiments, the fibrils of α-syn propagate similarly to prions but there is still insufficient evidence to establish this finding in humans. Here, we analysed the protein structure of these aggregates in the autopsy brains of patients by synchrotron Fourier-transform infrared micro-spectroscopy (FTIRM) analysis without extracting or artificially amplifying the aggregates. As a result, we found that the content of the ß-sheet structure in LBs in patients with PD was significantly higher than that in GCIs in patients with MSA (52.6 ± 1.9% in PD vs. 38.1 ± 0.9% in MSA, P < 0.001). These structural differences may provide clues to the differences in phenotypes of PD and MSA.


Assuntos
Citoplasma/metabolismo , Corpos de Inclusão/química , Corpos de Lewy/química , Neuroglia/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Idoso , Idoso de 80 Anos ou mais , Autopsia , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/metabolismo , Doença de Parkinson/metabolismo
12.
Nat Genet ; 52(2): 146-159, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32060489

RESUMO

In many repeat diseases, such as Huntington's disease (HD), ongoing repeat expansions in affected tissues contribute to disease onset, progression and severity. Inducing contractions of expanded repeats by exogenous agents is not yet possible. Traditional approaches would target proteins driving repeat mutations. Here we report a compound, naphthyridine-azaquinolone (NA), that specifically binds slipped-CAG DNA intermediates of expansion mutations, a previously unsuspected target. NA efficiently induces repeat contractions in HD patient cells as well as en masse contractions in medium spiny neurons of HD mouse striatum. Contractions are specific for the expanded allele, independently of DNA replication, require transcription across the coding CTG strand and arise by blocking repair of CAG slip-outs. NA-induced contractions depend on active expansions driven by MutSß. NA injections in HD mouse striatum reduce mutant HTT protein aggregates, a biomarker of HD pathogenesis and severity. Repeat-structure-specific DNA ligands are a novel avenue to contract expanded repeats.


Assuntos
Proteína Huntingtina/genética , Doença de Huntington/genética , Naftiridinas/farmacologia , Quinolonas/farmacologia , Expansão das Repetições de Trinucleotídeos/efeitos dos fármacos , Animais , Corpo Estriado/efeitos dos fármacos , DNA/metabolismo , Reparo de Erro de Pareamento de DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Proteína Huntingtina/metabolismo , Doença de Huntington/tratamento farmacológico , Doença de Huntington/patologia , Masculino , Camundongos , Camundongos Transgênicos , Instabilidade de Microssatélites , Mutação , Ribonucleases/metabolismo , Proteína de Ligação a TATA-Box/genética , Transcrição Gênica
13.
Mov Disord ; 35(2): 256-267, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31643109

RESUMO

OBJECTIVE: Alpha-synuclein (α-syn) is a major component of Lewy bodies, which are the pathological hallmark in Parkinson's disease, and its genetic mutations cause familial forms of Parkinson's disease. Patients with α-syn G51D mutation exhibit severe clinical symptoms. However, in vitro studies showed low propensity for α-syn with the G51D mutation. We studied the mechanisms associated with severe neurotoxicity of α-syn G51D mutation using a murine model generated by G51D α-syn fibril injection into the brain. METHODS: Structural analysis of wild-type and G51D α-syn-fibrils were performed using Fourier transform infrared spectroscopy. The ability of α-syn fibrils forming aggregates was first assessed in in vitro mammalian cells. An in vivo mouse model with an intranigral injection of α-syn fibrils was then used to evaluate the propagation pattern of α-syn and related cellular changes. RESULTS: We found that G51D α-syn fibrils have higher ß-sheet contents than wild-type α-syn fibrils. The addition of G51D α-syn fibrils to mammalian cells overexpressing α-syn resulted in the formation of phosphorylated α-syn inclusions at a higher rate. Similarly, an injection of G51D α-syn fibrils into the substantia nigra of a mouse brain induced more widespread phosphorylated α-syn pathology. Notably, the mice injected with G51D α-syn fibrils exhibited progressive nigral neuronal loss accompanied with mitochondrial abnormalities and motor impairment. CONCLUSION: Our findings indicate that the structural difference of G51D α-syn fibrils plays an important role in the rapidly developed and more severe neurotoxicity of G51D mutation-linked Parkinson's disease. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Corpos de Lewy/patologia , Doença de Parkinson/patologia , Substância Negra/patologia , alfa-Sinucleína/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Humanos , Corpos de Inclusão/metabolismo , Corpos de Lewy/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mutação/genética , Doença de Parkinson/genética , Fosforilação , Substância Negra/metabolismo
14.
Proc Natl Acad Sci U S A ; 116(36): 17963-17969, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427526

RESUMO

Many neurodegenerative diseases are characterized by the accumulation of abnormal protein aggregates in the brain. In Parkinson's disease (PD), α-synuclein (α-syn) forms such aggregates called Lewy bodies (LBs). Recently, it has been reported that aggregates of α-syn with a cross-ß structure are capable of propagating within the brain in a prionlike manner. However, the presence of cross-ß sheet-rich aggregates in LBs has not been experimentally demonstrated so far. Here, we examined LBs in thin sections of autopsy brains of patients with PD using microbeam X-ray diffraction (XRD) and found that some of them gave a diffraction pattern typical of a cross-ß structure. This result confirms that LBs in the brain of PD patients contain amyloid fibrils with a cross-ß structure and supports the validity of in vitro propagation experiments using artificially formed amyloid fibrils of α-syn. Notably, our finding supports the concept that PD is a type of amyloidosis, a disease featuring the accumulation of amyloid fibrils of α-syn.


Assuntos
Amiloide/metabolismo , Amiloidose/metabolismo , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Amiloide/química , Amiloidose/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Corpos de Lewy/metabolismo , Camundongos , Doença de Parkinson/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Difração de Raios X
15.
J Neurosci ; 39(38): 7615-7627, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31346030

RESUMO

Neuropathic pain is a chronic condition that occurs frequently after nerve injury and induces hypersensitivity or allodynia characterized by aberrant neuronal excitability in the spinal cord dorsal horn. Fibronectin leucine-rich transmembrane protein 3 (FLRT3) is a modulator of neurite outgrowth, axon pathfinding, and cell adhesion, which is upregulated in the dorsal horn following peripheral nerve injury. However, the function of FLRT3 in adults remains unknown. Therefore, we aimed to investigate the involvement of spinal FLRT3 in neuropathic pain using rodent models. In the dorsal horns of male rats, FLRT3 protein levels increased at day 4 after peripheral nerve injury. In the DRG, FLRT3 was expressed in activating transcription factor 3-positive, injured sensory neurons. Peripheral nerve injury stimulated Flrt3 transcription in the DRG but not in the spinal cord. Intrathecal administration of FLRT3 protein to naive rats induced mechanical allodynia and GluN2B phosphorylation in the spinal cord. DRG-specific FLRT3 overexpression using adeno-associated virus also produced mechanical allodynia. Conversely, a function-blocking FLRT3 antibody attenuated mechanical allodynia after partial sciatic nerve ligation. Therefore, FLRT3 derived from injured DRG neurons increases dorsal horn excitability and induces mechanical allodynia.SIGNIFICANCE STATEMENT Neuropathic pain occurs frequently after nerve injury and is associated with abnormal neuronal excitability in the spinal cord. Fibronectin leucine-rich transmembrane protein 3 (FLRT3) regulates neurite outgrowth and cell adhesion. Here, nerve injury increased FLRT3 protein levels in the spinal cord dorsal root, despite the fact that Flrt3 transcripts were only induced in the DRG. FLRT3 protein injection into the rat spinal cord induced mechanical hypersensitivity, as did virus-mediated FLRT3 overexpression in DRG. Conversely, FLRT3 inhibition with antibodies attenuated mechanically induced pain after nerve damage. These findings suggest that FLRT3 is produced by injured DRG neurons and increases neuronal excitability in the dorsal horn, leading to pain sensitization. Neuropathic pain induction is a novel function of FLRT3.


Assuntos
Gânglios Espinais/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuralgia/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , Animais , Humanos , Hiperalgesia/metabolismo , Ligadura , Masculino , Glicoproteínas de Membrana/farmacologia , Ratos , Ratos Wistar , Nervo Isquiático/lesões , Nervo Isquiático/cirurgia , Corno Dorsal da Medula Espinal/efeitos dos fármacos
16.
PLoS One ; 14(6): e0218261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242217

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, which is characterized by progressive motor dysfunction as well as non-motor symptoms. Pathological and genetic studies have demonstrated that α-synuclein (αSyn) plays key roles in the pathogenesis of PD. Although several missense mutations in the αSyn gene have been identified as causes of familial PD, the mechanisms underlying the variance in the clinical phenotypes of familial PD caused by different mutations remain elusive. Here, we established novel Drosophila models expressing either wild-type (WT) αSyn or one of five αSyn mutants (A30P, E46K, H50Q, G51D, and A53T) using site-specific transgenesis, which express transgenes at equivalent levels. Expression of either WT or mutant αSyn in the compound eyes by the GMR-GAL4 driver caused mild rough eye phenotypes with no obvious difference among the mutants. Upon pan-neuronal expression by the nSyb-GAL4 driver, these αSyn-expressing flies showed a progressive decline in locomotor function. Notably, we found that E46K, H50Q, G51D, and A53T αSyn-expressing flies showed earlier onset of locomotor dysfunction than WT αSyn-expressing flies, suggesting their enhanced toxic effects. Whereas mRNA levels of WT and mutant αSyn were almost equivalent, we found that protein expression levels of E46K αSyn were higher than those of WT αSyn. In vivo chase experiments using the drug-inducible GMR-GeneSwitch driver demonstrated that degradation of E46K αSyn protein was significantly slower than WT αSyn protein, indicating that the E46K αSyn mutant gains resistance to degradation in vivo. We therefore conclude that our novel site-specific transgenic fly models expressing either WT or mutant αSyn are useful to explore the mechanisms by which different αSyn mutants gain toxic functions in vivo.


Assuntos
Mutação de Sentido Incorreto , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Drosophila , Humanos , Doença de Parkinson/patologia , Proteólise , alfa-Sinucleína/genética
17.
Sci Rep ; 9(1): 7567, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31110191

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease caused by the loss of dopaminergic neurons in the substantia nigra. A characteristic pathological feature of PD is cytoplasmic accumulation of α-synuclein (SNCA) protein. Multiplication of the SNCA gene in familial PD and pathological accumulation of SNCA protein during progression of sporadic PD suggest that increased SNCA protein levels increase the risk of PD. Thus, reducing SNCA expression levels could delay PD onset or modify the disease course. For efficient knock down, we designed and synthesized an amido-bridged nucleic acids (AmNA)-modified antisense oligonucleotide (ASO) that targeted SNCA with improved stability and cellular uptake in vivo. AmNA-ASO efficiently downregulated SNCA at both the mRNA and protein level in vitro and in vivo. Notably, AmNA-ASO was efficiently delivered into the mouse brain by intracerebroventricular injection without the aid of additional chemicals. Furthermore, administration of AmNA-ASO ameliorated neurological defects in PD model mice expressing human wild type SNCA. Taken together, these findings suggest that AmNA-ASO is a promising therapeutic strategy for SNCA-associated pathology in PD.


Assuntos
Doença de Parkinson/terapia , RNA Antissenso/genética , Terapêutica com RNAi/métodos , alfa-Sinucleína/genética , Animais , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Oligonucleotídeos/genética , RNA Antissenso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , alfa-Sinucleína/metabolismo
18.
Adv Healthc Mater ; 8(10): e1900130, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30946540

RESUMO

Neural interfaces enabling light transmittance rely on optogenetics to control and monitor specific neural activity, thereby facilitating deeper understanding of intractable diseases. This study reports the material strategy underlying an optogenetic neural interface comprising stretchable and transparent conductive tracks and capable of demonstrating high biocompatibility after long-term (5-month) implantation. Ag/Au core-shell nanowires contribute toward improving track performance in terms of stretchability (<60% strain), transparency (<83%), and electrical resistance (15 Ω sq-1 ). The neural interface integrated with gel-coated exterior microelectrodes preserves low impedance (1.1-3.2 Ω cm2 ) in a saline solution over the evaluated 5-month period. Besides the use of efficient conductive materials, surface treatment using antithrombogenic polymer tends to prevent the growth of granulation tissue, thereby facilitating clear monitoring of electrocorticograms (ECoG) in a rodent during chronic implantation. The flexible and transparent neural interface pathologically exhibits noncytotoxicity and low inflammatory response while efficiently recording evoked ECoG in a nonhuman primate via optogenetic stimulation. The proposed highly reliable interface can be employed in multifaceted approaches for translational research based on chronic implants.


Assuntos
Córtex Cerebral/fisiologia , Ouro/química , Nanofios/química , Optogenética/métodos , Prata/química , Animais , Impedância Elétrica , Eletrocorticografia , Eletrodos Implantados , Potenciais Somatossensoriais Evocados/fisiologia , Álcool de Polivinil/química , Ratos
19.
J Neurosci Methods ; 322: 23-33, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30946879

RESUMO

BACKGROUND: Callithrix jacchus, generally known as the common marmoset, has recently garnered interest as an experimental primate model for better understanding the basis of human social behavior, architecture and function. Modelling human neurological and psychological diseases in marmosets can enhance the knowledge obtained from rodent research for future pre-clinical studies. Hence, comprehensive and quantitative assessments of marmoset behaviors are crucial. However, systems for monitoring and analyzing marmoset behaviors have yet to be established. NEW METHOD: In this paper, we present a novel multimodal system, MarmoDetector, for the automated 3D analysis of marmoset behavior under freely moving conditions. MarmoDetector allows the quantitative assessment of marmoset behaviors using computerised tracking analysis techniques that are based on a Kinect system equipped with video recordings, infrared images and depth analysis. RESULTS: Using MarmoDetector, we assessed behavioral circadian rhythms continuously over several days in home cages. In addition, MarmoDetector detected acute, transient complex behaviors of alcohol injected marmosets. COMPARISON TO EXISTING METHOD: Compared to 2D recording, MarmoDetector detects activities more precisely and is very sensitive as we could detect behavioral defects specifically induced by alcohol administration. CONCLUSION: MarmoDetector facilitates the rapid and accurate analysis of marmoset behavior and will enhance research on the neural basis of brain disorders.


Assuntos
Comportamento Animal , Callithrix , Reconhecimento Automatizado de Padrão/métodos , Animais , Ritmo Circadiano , Feminino , Processamento de Imagem Assistida por Computador , Masculino , Atividade Motora , Gravação em Vídeo
20.
Biol Pharm Bull ; 41(10): 1615-1619, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30270333

RESUMO

In recent times, oncolytic viruses expressing an extraneous gene have attracted great interest; in fact, they have been engaged in multiple applications, such as medicine for cancer. Our group made an oncolytic adenovirus, namely, OBP-301, for use in treating solid cancers and press clinical trial to get approval for a pharmaceutical product. In this study, we applied a flow cytometry-based method to determine the titer of adenoviruses expressing an extraneous gene as well as assess their quality. We considered using the green fluorescent protein (GFP)50 titer as a measure of viral quality. The GFP50 titer (GFP50/mL) is the viral load required to render the HeLa S3 cell line 50% GFP-positive by analysing flow cytometry data. We measured the GFP50 titers for three types of recombinant adenoviruses (OBP-401, OBP-1101, and OBP-1106). We compared GFP50/mL and tissue culture infectious dose (TCID50/mL), a conventional titration index, and found that these titers showed a linear correlation, with a correlation coefficient of >0.9. Moreover, GFP50/mL showed high repetitive accuracy. We expect this flow cytometry-based method to be useful in case of clinically relevant viruses expressing an extraneous gene, in particular, to control viral quality.


Assuntos
Adenoviridae/genética , Proteínas de Fluorescência Verde/genética , Vírus Oncolíticos/genética , Infecções por Adenoviridae/virologia , Linhagem Celular Tumoral , Citometria de Fluxo/métodos , Células HeLa , Humanos , Microrganismos Geneticamente Modificados , Carga Viral
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