Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 191
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Am J Pathol ; 193(9): 1208-1222, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37328100

RESUMO

Oral submucous fibrosis (OSF) is a potentially malignant disorder of the oral mucosa; however, whether and how the fibrotic matrix of OSF is involved in the malignant transformation of epithelial cells remains unknown. Herein, oral mucosa tissue from patients with OSF, OSF rat models, and their controls were used to observe the extracellular matrix changes and epithelial-mesenchymal transformation (EMT) in fibrotic lesions. Compared with controls, oral mucous tissues from patients with OSF showed an increased number of myofibroblasts, a decreased number of blood vessels, and increased type I and type III collagen levels. In addition, the oral mucous tissues from humans and OSF rats showed increased stiffness, accompanied by increased EMT activities of epithelial cells. The EMT activities of stiff construct-cultured epithelial cells were increased significantly by exogenous piezo-type mechanosensitive ion channel component 1 (Piezo1) activation, and decreased by yes-associated protein (YAP) inhibition. During ex vivo implantation, oral mucosal epithelial cells of the stiff group showed increased EMT activities and increased levels of Piezo1 and YAP compared with those in the sham and soft groups. These results indicate that increased stiffness of the fibrotic matrix in OSF led to increased proliferation and EMT of mucosal epithelial cells, in which the Piezo1-YAP signal transduction is important.


Assuntos
Fibrose Oral Submucosa , Humanos , Ratos , Animais , Fibrose Oral Submucosa/metabolismo , Fibrose Oral Submucosa/patologia , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Transição Epitelial-Mesenquimal , Miofibroblastos/metabolismo , Células Epiteliais/metabolismo
2.
Brain ; 146(8): 3373-3391, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36825461

RESUMO

GGC repeat expansion in the 5' untranslated region (UTR) of NOTCH2NLC is associated with a broad spectrum of neurological disorders, especially neuronal intranuclear inclusion disease (NIID). Studies have found that GGC repeat expansion in NOTCH2NLC induces the formation of polyglycine (polyG)-containing protein, which is involved in the formation of neuronal intranuclear inclusions. However, the mechanism of neurotoxicity induced by NOTCH2NLC GGC repeats is unclear. Here, we used NIID patient-specific induced pluripotent stem cell (iPSC)-derived 3D cerebral organoids (3DCOs) and cellular models to investigate the pathophysiological mechanisms of NOTCH2NLC GGC repeat expansion. IPSC-derived 3DCOs and cellular models showed the deposition of polyG-containing intranuclear inclusions. The NOTCH2NLC GGC repeats could induce the upregulation of autophagic flux, enhance integrated stress response and activate EIF2α phosphorylation. Bulk RNA sequencing for iPSC-derived neurons and single-cell RNA sequencing (scRNA-seq) for iPSC-derived 3DCOs revealed that NOTCH2NLC GGC repeats may be associated with dysfunctions in ribosome biogenesis and translation. Moreover, NOTCH2NLC GGC repeats could induce the NPM1 nucleoplasm translocation, increase nucleolar stress, impair ribosome biogenesis and induce ribosomal RNA sequestration, suggesting dysfunction of membraneless organelles in the NIID cellular model. Dysfunctions in ribosome biogenesis and phosphorylated EIF2α and the resulting increase in the formation of G3BP1-positive stress granules may together lead to whole-cell translational inhibition, which may eventually cause cell death. Interestingly, scRNA-seq revealed that NOTCH2NLC GGC repeats may be associated with a significantly decreased proportion of immature neurons while 3DCOs were developing. Together, our results underscore the value of patient-specific iPSC-derived 3DCOs in investigating the mechanisms of polyG diseases, especially those caused by repeats in human-specific genes.


Assuntos
DNA Helicases , RNA Helicases , Humanos , Proteínas de Ligação a Poli-ADP-Ribose , Proteínas com Motivo de Reconhecimento de RNA , Regiões 5' não Traduzidas , Corpos de Inclusão Intranuclear , Ribossomos , Expansão das Repetições de Trinucleotídeos/genética
3.
Molecules ; 29(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675549

RESUMO

Derived from hazelnuts, hazel leaf has been utilized in traditional folk medicine for centuries in countries such as Portugal, Sweden, and Iran. In our previous investigations, we conducted a preliminary assessment of the hazel leaf polyphenol extract (referred to as ZP) and identified nine compounds, such as kaempferol and chlorogenic acid, in its composition. ZP has shown promising properties as an antioxidant and anti-inflammatory agent. Our research has revealed that ZP has protective effects against cisplatin-induced acute kidney injury (AKI). We conducted a comprehensive examination of both the pathological and ultrastructural aspects and found that ZP effectively ameliorated renal tissue lesions and mitigated mitochondrial damage. Moreover, ZP significantly suppressed malondialdehyde levels while increasing glutathione and catalase concentrations in the kidneys of AKI-induced mice. ZP decreased the number of apoptotic cells and decreased pro-apoptotic protein expression in the kidneys of mice and human renal tubular epithelial cells (HK-2). Furthermore, treatment with ZP increased the levels of proteins marking anti-ferroptosis, such as GPX4, FTH1, and FSP1, in experiments both in vivo and in vitro. We elucidated the underlying mechanisms of ZP's actions, revealing its inhibitory effect on Yap phosphorylation and its regulation of Lats expression, which exert a protective influence on the kidneys. Furthermore, we found that inhibiting the Hippo pathway compromised ZP's nephroprotective effects in both in vitro and in vivo studies. In summary, this research shows that ZP exhibits renoprotective properties, effectively reducing oxidative damage, apoptosis, and ferroptosis in the kidneys by targeting the Hippo pathway.


Assuntos
Injúria Renal Aguda , Cisplatino , Ferroptose , Via de Sinalização Hippo , Extratos Vegetais , Folhas de Planta , Polifenóis , Transdução de Sinais , Animais , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/induzido quimicamente , Ferroptose/efeitos dos fármacos , Cisplatino/efeitos adversos , Polifenóis/farmacologia , Polifenóis/química , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Folhas de Planta/química , Proteínas Serina-Treonina Quinases/metabolismo , Masculino , Linhagem Celular , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(3): 244-249, 2024 Mar 15.
Artigo em Zh | MEDLINE | ID: mdl-38557375

RESUMO

OBJECTIVES: To investigate the effects of antenatal corticosteroid (ACS) therapy in pregnant women on the brain development of preterm infants using amplitude-integrated electroencephalography (aEEG). METHODS: A retrospective analysis was conducted on 211 preterm infants with a gestational age of 28 to 34+6 weeks. The infants were divided into an ACS group (131 cases) and a control group (80 cases) based on whether antenatal dexamethasone was given for promoting fetal lung maturity. The first aEEG monitoring (referred to as aEEG1) was performed within 24 hours after birth, and the second aEEG monitoring (referred to as aEEG2) was performed between 5 to 7 days after birth. The aEEG results were compared between the two groups. RESULTS: In preterm infants with a gestational age of 28 to 31+6 weeks, the ACS group showed a more mature periodic pattern and higher lower amplitude boundary in aEEG1 compared to the control group (P<0.05). In preterm infants with a gestational age of 32 to 33+6 weeks and 34 to 34+6 weeks, the ACS group showed a higher proportion of continuous patterns, more mature periodic patterns and higher Burdjalov scores in aEEG1 (P<0.05). And the ACS group exhibited a higher proportion of continuous patterns, more mature periodic patterns, higher lower amplitude boundaries, narrower bandwidths, and higher Burdjalov scores in aEEG2 (P<0.05). CONCLUSIONS: ACS-treated preterm infants have more mature aEEG patterns compared to those not treated with ACS, suggesting a beneficial effect of ACS on the brain development of preterm infants.


Assuntos
Recém-Nascido Prematuro , Gestantes , Lactente , Recém-Nascido , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Eletroencefalografia/métodos , Idade Gestacional , Encéfalo
5.
Mov Disord ; 38(12): 2258-2268, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37990409

RESUMO

BACKGROUND: Patients with Parkinson's disease (PD) have consistently demonstrated brain structure abnormalities, indicating the presence of shared etiological and pathological processes between PD and brain structures; however, the genetic relationship remains poorly understood. OBJECTIVE: The aim of this study was to investigate the extent of shared genetic architecture between PD and brain structural phenotypes (BSPs) and to identify shared genomic loci. METHODS: We used the summary statistics from genome-wide association studies to conduct MiXeR and conditional/conjunctional false discovery rate analyses to investigate the shared genetic signatures between PD and BSPs. Subsequent expression quantitative trait loci mapping in the human brain and enrichment analyses were also performed. RESULTS: MiXeR analysis identified genetic overlap between PD and various BSPs, including total cortical surface area, average cortical thickness, and specific brain volumetric structures. Further analysis using conditional false discovery rate (FDR) identified 21 novel PD risk loci on associations with BSPs at conditional FDR < 0.01, and the conjunctional FDR analysis demonstrated that PD shared several genomic loci with certain BSPs at conjunctional FDR < 0.05. Among the shared loci, 16 credible mapped genes showed high expression in the brain tissues and were primarily associated with immune function-related biological processes. CONCLUSIONS: We confirmed the polygenic overlap with mixed directions of allelic effects between PD and BSPs and identified multiple shared genomic loci and risk genes, which are likely related to immune-related biological processes. These findings provide insight into the complex genetic architecture associated with PD. © 2023 International Parkinson and Movement Disorder Society.


Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/genética , Predisposição Genética para Doença/genética , Fenótipo , Encéfalo/diagnóstico por imagem , Polimorfismo de Nucleotídeo Único/genética , Loci Gênicos
6.
EMBO Rep ; 22(5): e52141, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33764618

RESUMO

Tyrosine phosphorylation of secretion machinery proteins is a crucial regulatory mechanism for exocytosis. However, the participation of protein tyrosine phosphatases (PTPs) in different exocytosis stages has not been defined. Here we demonstrate that PTP-MEG2 controls multiple steps of catecholamine secretion. Biochemical and crystallographic analyses reveal key residues that govern the interaction between PTP-MEG2 and its substrate, a peptide containing the phosphorylated NSF-pY83 site, specify PTP-MEG2 substrate selectivity, and modulate the fusion of catecholamine-containing vesicles. Unexpectedly, delineation of PTP-MEG2 mutants along with the NSF binding interface reveals that PTP-MEG2 controls the fusion pore opening through NSF independent mechanisms. Utilizing bioinformatics search and biochemical and electrochemical screening approaches, we uncover that PTP-MEG2 regulates the opening and extension of the fusion pore by dephosphorylating the DYNAMIN2-pY125 and MUNC18-1-pY145 sites. Further structural and biochemical analyses confirmed the interaction of PTP-MEG2 with MUNC18-1-pY145 or DYNAMIN2-pY125 through a distinct structural basis compared with that of the NSF-pY83 site. Our studies thus provide mechanistic insights in complex exocytosis processes.


Assuntos
Proteínas Tirosina Fosfatases não Receptoras , Proteínas Tirosina Fosfatases , Peptídeos , Fosforilação , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo
7.
J Headache Pain ; 24(1): 111, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592229

RESUMO

BACKGROUND: While previous genome-wide association studies (GWAS) have identified multiple risk variants for migraine, there is a lack of evidence about how these variants contribute to the development of migraine. We employed an integrative pipeline to efficiently transform genetic associations to identify causal genes for migraine. METHODS: We conducted a proteome-wide association study (PWAS) by combining data from the migraine GWAS data with proteomic data from the human brain and plasma to identify proteins that may play a role in the risk of developing migraine. We also combined data from GWAS of migraine with a novel joint-tissue imputation (JTI) prediction model of 17 migraine-related human tissues to conduct transcriptome-wide association studies (TWAS) together with the fine mapping method FOCUS to identify disease-associated genes. RESULTS: We identified 13 genes in the human brain and plasma proteome that modulate migraine risk by regulating protein abundance. In addition, 62 associated genes not reported in previous migraine TWAS studies were identified by our analysis of migraine using TWAS and fine mapping. Five genes including ICA1L, TREX1, STAT6, UFL1, and B3GNT8 showed significant associations with migraine at both the proteome and transcriptome, these genes are mainly expressed in ependymal cells, neurons, and glial cells, and are potential target genes for prevention of neuronal signaling and inflammatory responses in the pathogenesis of migraine. CONCLUSIONS: Our proteomic and transcriptome findings have identified disease-associated genes that may give new insights into the pathogenesis and potential therapeutic targets for migraine.


Assuntos
Transtornos de Enxaqueca , Proteoma , Humanos , Proteoma/genética , Estudo de Associação Genômica Ampla , Proteômica , Transcriptoma , Transtornos de Enxaqueca/genética
8.
BMC Genomics ; 23(1): 822, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36510145

RESUMO

BACKGROUND: A loss-of-function mutation in ATPase phospholipid transporting 11-B (putative) (ATP11B) gene causing cerebral small vessel disease (SVD) in vivo, and a single intronic nucleotide polymorphism in ATP11B: rs148771930 that was associated with white matter hyperintensities burden in European patients with SVD, was recently identified. Our results suggest that ATP11B may not play an essential role in SVD in the Chinese population. RESULTS: We performed target region sequencing including ATP11B gene in 182 patients with sporadic SVD, and identified five rare variants and two novel variants of ATP11B. A case-control study was then performed in 524 patients and matched 550 controls to investigate the relationship between ATP11B and sporadic SVD in the Chinese Han population. Although none of these variants were significantly associated with SVD in our samples, it is important to mention that we identified a novel variant, p. G238W, which was predicted to be pathogenic in silico. This variant was present in our cohort of patients with an extremely low frequency and was absent in the controls. CONCLUSION: Our results suggest that ATP11B may not play an essential role in SVD in the Chinese population.


Assuntos
Adenosina Trifosfatases , Doenças de Pequenos Vasos Cerebrais , População do Leste Asiático , Humanos , Estudos de Casos e Controles , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/patologia , Polimorfismo de Nucleotídeo Único , Adenosina Trifosfatases/genética
9.
Ann Neurol ; 89(1): 182-187, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33016348

RESUMO

NOTCH2NLC GGC repeat expansions were recently identified in neuronal intranuclear inclusion disease (NIID); however, it remains unclear whether they occur in other neurodegenerative disorders. This study aimed to investigate the role of intermediate-length NOTCH2NLC GGC repeat expansions in Parkinson disease (PD). We screened for GGC repeat expansions in a cohort of 1,011 PD patients and identified 11 patients with intermediate-length repeat expansions ranging from 41 to 52 repeats, with no repeat expansions in 1,134 controls. Skin biopsy revealed phospho-alpha-synuclein deposition, confirming the PD diagnosis in 2 patients harboring intermediate-length repeat expansions instead of NIID or essential tremor. Fibroblasts from PD patients harboring intermediate-length repeat expansions revealed NOTCH2NLC upregulation and autophagic dysfunction. Our results suggest that intermediate-length repeat expansions in NOTCH2NLC are potentially associated with PD. ANN NEUROL 2021;89:182-187.


Assuntos
Doenças Neurodegenerativas/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Adulto , Idoso , Biópsia , Encéfalo/patologia , Estudos de Coortes , Feminino , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Linhagem , Receptor Notch2/metabolismo
10.
Molecules ; 27(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36235001

RESUMO

In this paper, a new aqueous two-phase extraction system(ATPES) consisting of UCON (poly(ethylene glycol-ran-propylene glycol) monobutyl ether)-NaH2PO4 was established, and four trace polycyclic aromatic hydrocarbons (PAHs: fluorene, anthracene, pyrene and phenanthrene) in water and soil were analyzed by high-performance liquid chromatography (HPLC)-ultraviolet detection. In the multi-factor experiment, the central composite design (CCD) was used to determine the optimum technological conditions. The final optimal conditions were as follows: the concentration of UCON was 0.45 g·mL-1, the concentration of NaH2PO4 was 3.5 mol·L-1, and the temperature was 30 °C. The recovery of the four targets was 98.91-99.84% with a relative standard deviation of 0.3-2.1%. Then UCON recycling and cyclic tests were designed in the experiment, and the results showed that the recovery of PAHs gradually increased in the three extractions because of the remaining PAHs in the salt phase of last extraction. The recovery of PAHs in the UCON recycling test was less than that in the extraction test due to the wastage of UCON. In addition, a two-phase aqueous extraction model was established based on the random forest (RF) model. The results obtained were compared with the experimental data, and the root mean square error (RMSE) was 0.0371-0.0514 and the correlation coefficient R2 was 96.20-98.53%, proving that the model is robust and reliable.


Assuntos
Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Antracenos/análise , Cromatografia Líquida de Alta Pressão/métodos , Éteres , Etilenoglicóis , Fluorenos , Fenantrenos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Propilenoglicóis , Pirenos , Solo , Extração em Fase Sólida/métodos , Água/química , Poluentes Químicos da Água/química
11.
Medicina (Kaunas) ; 58(4)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35454378

RESUMO

This prospective comparative case series aims to compare best-corrected visual acuity (BCVA), retinal microvasculature, and retinal structural changes in patients treated with either ranibizumab or aflibercept for macular edema (ME) secondary to treatment-naïve branch retinal vein occlusion (BRVO) by optical coherence tomography angiography (OCTA). Ten patients were enrolled with macular capillary density of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) and foveal avascular zone (FAZ) measured in both eyes before and after treatment. Final central retinal thickness and BCVA improved significantly (p < 0.05), and densities of SCP and DCP of BRVO sectors were significantly lower at baseline than fellow eye counterparts and remained persistently lower during treatment, particularly in the aflibercept group (p < 0.05). SCP density, DCP density of both BRVO sectors (p = 0.0001, p < 0.0001), and non-BRVO sectors (p < 0.0001, p < 0.0001) were significantly correlated with final BCVA for diseased eyes. Using multivariate general linear model analysis, and including OCTA parameters only, but not all of the available clinical data, DCP density of BRVO sectors in both eyes was the most predictive factor for final visual outcome (probability p < 0.0001). OCTA offered further qualitative and quantitative evaluation of treatment-naïve BRVO. Judging by OCTA parameters, not only in the diseased eye but also in the fellow eye, DCP density of BRVO sectors was the most predictive factor of final visual outcome.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Edema Macular/complicações , Edema Macular/etiologia , Estudos Prospectivos , Ranibizumab/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/tratamento farmacológico , Vasos Retinianos , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual
12.
Nanotechnology ; 33(10)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34844227

RESUMO

In order to evaluate the effect of precursors and synthesis strategies on catalytic ability of Mo2C in the hydrogen evolution reaction (HER), four kinds of Mo2C were synthesized using two kinds of MoO3by two strategies. Compared with the one-step direct carbonization strategy, Mo2C with a large special surface area and a better performance could be synthesized by the two-step strategy composed of a nitridation reaction and a carbonization reaction. Additionally, the as-prepared porous Mo2C nanobelts (NBs) exhibit good electrocatalytic performance with a small overpotential of 165 mV (0.5 M H2SO4) and 124 mV (1 M KOH) at 10 mA cm-2, as well as a Tafel slope of 58 mV dec-1(0.5 M H2SO4) and 59 mV dec-1(1 M KOH). The excellent catalytic activity is ascribed to the nano crystallites and porous structure. What's more, the belt structure also facilitates the charge transport in the materials during the electrocatalytic HER process. Therefore, the two-step strategy provides a new insight into the structural design with superior performance for electrocatalytic HER.

13.
Exp Cell Res ; 395(1): 112169, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32653410

RESUMO

It has been reported that cholesterol-lowing agents can ameliorate severity of myocarditis. However, the beneficial effect of the agents has been claimed to be independent of cholesterol reduction as there is no significant change in the plasma cholesterol level in myocarditis. In the present study, using experimental autoimmune myocarditis (EAM) rats as an animal model, we demonstrated that EAM induced elevation of cholesterol level and impaired cholesterol efflux capacity in the cardiac tissue. Moreover, serum high-density lipoprotein (HDL) content was reduced and HDL function associated protein Paraoxonase 1 (PON1) activity was decreased. Besides, the major structural protein within HDL, Apolipoprotein A1 (ApoA1) expression in the cardiac tissues was significantly reduced while the level of serum ApoA1 was not significantly altered. Importantly, cholesterol depleting agent methyl-ß-cyclodextrin (MßCD) alleviated the development of EAM, as monitored by decreased ratio of heart weight to body weight (HW/BW), decreased infiltration of inflammatory cells and collagen deposition, improved cardiac function, reduced expression of apoptosis-related protein Bax, Fas, FasL and caspase-3 and increased level of anti-apoptotic protein Bcl-2. These results suggest that reduction of cholesterol level in cardiac tissue could suppress EAM-induced cardiac apoptosis through both intrinsic and extrinsic apoptotic pathways.


Assuntos
Apoptose/fisiologia , Doenças Autoimunes/imunologia , Colesterol/metabolismo , Hipercolesterolemia/metabolismo , Miocardite/metabolismo , Animais , Caspase 3/metabolismo , Colesterol/imunologia , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Masculino , Miocardite/imunologia , Miocárdio/metabolismo , Ratos
14.
PLoS Genet ; 14(9): e1007664, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30222779

RESUMO

CHIP (carboxyl terminus of heat shock 70-interacting protein) has long been recognized as an active member of the cellular protein quality control system given the ability of CHIP to function as both a co-chaperone and ubiquitin ligase. We discovered a genetic disease, now known as spinocerebellar autosomal recessive 16 (SCAR16), resulting from a coding mutation that caused a loss of CHIP ubiquitin ligase function. The initial mutation describing SCAR16 was a missense mutation in the ubiquitin ligase domain of CHIP (p.T246M). Using multiple biophysical and cellular approaches, we demonstrated that T246M mutation results in structural disorganization and misfolding of the CHIP U-box domain, promoting oligomerization, and increased proteasome-dependent turnover. CHIP-T246M has no ligase activity, but maintains interactions with chaperones and chaperone-related functions. To establish preclinical models of SCAR16, we engineered T246M at the endogenous locus in both mice and rats. Animals homozygous for T246M had both cognitive and motor cerebellar dysfunction distinct from those observed in the CHIP null animal model, as well as deficits in learning and memory, reflective of the cognitive deficits reported in SCAR16 patients. We conclude that the T246M mutation is not equivalent to the total loss of CHIP, supporting the concept that disease-causing CHIP mutations have different biophysical and functional repercussions on CHIP function that may directly correlate to the spectrum of clinical phenotypes observed in SCAR16 patients. Our findings both further expand our basic understanding of CHIP biology and provide meaningful mechanistic insight underlying the molecular drivers of SCAR16 disease pathology, which may be used to inform the development of novel therapeutics for this devastating disease.


Assuntos
Cognição , Atividade Motora/genética , Domínios Proteicos/genética , Ataxias Espinocerebelares/genética , Ubiquitina-Proteína Ligases/genética , Animais , Comportamento Animal , Sistemas CRISPR-Cas/genética , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Mutagênese Sítio-Dirigida , Fenótipo , Mutação Puntual , Multimerização Proteica/genética , Ratos , Ratos Sprague-Dawley , Ataxias Espinocerebelares/congênito , Ubiquitina-Proteína Ligases/metabolismo
15.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4187-4192, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34467731

RESUMO

The present study aimed to explore the effect of nuclear factor erythroid 2 related factor 2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway in intestinal protection by Sishen Pills against ulcerative colitis(UC). After the UC model was induced by 3% dextran sodium sulfate(DSS), experimental animals were randomly divided into control group, model group, salazosulfapyridine(SASP) group, and low-and high-dose Sishen Pills groups. Drug intervention(ig) was performed for seven consecutive days during modeling. On the 7 th day, the mice were euthanized. The body weight and colon length were recorded, and the histopathological changes of the colon were observed by HE staining. Serum interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), total antioxidant capacity(T-AOC), malondialdehyde(MDA), and reactive oxygen species(ROS) were detected by ELISA. The protein and mRNA expression of Nrf2, HO-1, and NADPH quinine oxidoreductase-1(NQO-1) was determined by Western blot and reverse transcription-polymerase chain reaction(RT-PCR). Compared with the normal group, the model group exhibited reduced body weight, colon length, and T-AOC, increased IL-6, TNF-α, MDA, and ROS, and diminished protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. Compared with the model group, the SASP group and high-dose Sishen Pills group showed elevated body weight, colon length, and T-AOC, lowered IL-6, TNF-α, MDA, and ROS levels, and increased protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. As assessed by HE staining, Sishen Pills could improve the pathological changes of the colon. The findings suggested that Sishen Pills could protect the colon against UC induced by 3% DSS. The specific mechanism of action may be related to the anti-inflammatory and anti-oxidative stress effects by the activation of the Nrf2/HO-1 signaling pathway.


Assuntos
Colite Ulcerativa , Fator 2 Relacionado a NF-E2 , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Sulfato de Dextrana , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais
16.
J Cell Mol Med ; 24(17): 10223-10232, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32720739

RESUMO

The rs619586 polymorphism has been shown to alter the expression of MALAT1, which act as a competing endogenous RNA (ceRNA) against miR-145. And miR-145 was found to target COL5A1, the interaction between which was shown to be involved in the pathogenesis of invasive meningioma. In this study, we aimed to explore the effect of rs619586 polymorphism and its underlying molecular mechanism in invasive meningioma. Real-time PCR and Western Blot analysis were used to study the differentiated expression of miR-145, MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) and COL5A1 (collagen alpha-1(V) chain) in tumour/serum samples genotyped as rs619586 AA, AG and GG. Computational analysis and luciferase reporter assay were also conducted to identify the regulatory relationship between miR-145 and MALAT1/COL5A1. Meanwhile, expression of miR-145 and COL5A1 in different cell treatment groups was measured to validate the results obtained from earlier experiments. As shown by the results and in tumour/serum samples genotyped as AA, AG and GG, the expression of both MALAT1 and COL5A1 was down-regulated in a stepwise fashion, while the expression of miR-145 was increased, suggesting a potential negative relationship between MALAT1/COL5A1 and miR-145. Meanwhile, miR-145 was shown to bind to MALAT1, while COL5A1 was identified as a virtual target gene of miR-145. As a consequence, a MALAT1/miR-145/COL5A1 molecular pathway was established based on the above results. In particular, with the presence of rs619586 A>G polymorphism, the expression of MALAT1 and COL5A1 was both reduced, leading to reduced invasiveness of meningioma.


Assuntos
Colágeno Tipo V/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Invasividade Neoplásica/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Alelos , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Cultivadas , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
17.
J Biol Chem ; 294(50): 19236-19245, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31619515

RESUMO

Monogenetic disorders that cause cerebellar ataxia are characterized by defects in gait and atrophy of the cerebellum; however, patients often suffer from a spectrum of disease, complicating treatment options. Spinocerebellar ataxia autosomal recessive 16 (SCAR16) is caused by coding mutations in STUB1, a gene that encodes the multifunctional enzyme CHIP (C terminus of HSC70-interacting protein). The disease spectrum of SCAR16 includes a varying age of disease onset, cognitive dysfunction, increased tendon reflex, and hypogonadism. Although SCAR16 mutations span the multiple functional domains of CHIP, it is unclear whether the location of the mutation and the change in the biochemical properties of CHIP contributes to the clinical spectrum of SCAR16. In this study, we examined relationships between the clinical phenotypes of SCAR16 patients and the changes in biophysical, biochemical, and functional properties of the corresponding mutated protein. We found that the severity of ataxia did not correlate with age of onset; however, cognitive dysfunction, increased tendon reflex, and ancestry were able to predict 54% of the variation in ataxia severity. We further identified domain-specific relationships between biochemical changes in CHIP and clinical phenotypes and specific biochemical activities that associate selectively with either increased tendon reflex or cognitive dysfunction, suggesting that specific changes to CHIP-HSC70 dynamics contribute to the clinical spectrum of SCAR16. Finally, linear models of SCAR16 as a function of the biochemical properties of CHIP support the concept that further inhibiting mutant CHIP activity lessens disease severity and may be useful in the design of patient-specific targeted approaches to treat SCAR16.


Assuntos
Proteínas de Choque Térmico HSC70/metabolismo , Transtornos do Neurodesenvolvimento/metabolismo , Ataxias Espinocerebelares/metabolismo , Proteínas de Choque Térmico HSC70/genética , Humanos , Método de Monte Carlo , Análise Multivariada , Mutação , Transtornos do Neurodesenvolvimento/genética , Fenótipo , Ataxias Espinocerebelares/genética
18.
Opt Express ; 28(18): 26218-26227, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32906898

RESUMO

We propose and theoretically demonstrate a highly sensitive optofluidic refractive index (RI) sensor based on a spectral filter formed by a segment of liquid-filled seven-hole Teflon-cladding fiber sandwiched by two standard single mode fibers (SMFs). When liquid flows through the air hole channels of the seven-hole Teflon-cladding fiber, it forms a seven-liquid-core fiber (SLCF) and the lightwaves are well guided by the liquid cores owing to total inner reflection. When the input SMF is aligned to the central core of the SLCF, the light excited in the central core will couple to outer cores periodically along the length of the SCLF. At the detection port, the output SMF is also aligned to the central core of the SLCF. Since the coupling coefficient depends on wavelength, the coupling efficiency is also wavelength dependent, leading to a filter spectrum for a given length of the SLCF. The spectral response of the filter to the change in RI of the liquid cores is numerically simulated based on the coupled-mode theory through finite-element method. The dependence of the RI sensitivity on the diameter and pitch of air holes of the SLCF are studied, respectively. Finally, a very high sensitivity of 25,300 nm/RIU for RI around 1.333 is achieved.

19.
Exp Cell Res ; 375(1): 22-30, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557558

RESUMO

Family members of peroxisome proliferator-activated receptors (PPARs), such as PPARγ, have been shown to be effective in regulating T helper 17 (Th17) cell differentiation. However, whether PPARα, another important family member of PPARs, contributes to Th17 cell differentiation remains controversial. In the present study, we show that PPARα may be a negative regulator of Th17 cell differentiation. In CD4+ T cells from PPARα knockout mice, PPARα deficiency enhances IL-17 and IL-6 levels and promotes Th17 cell differentiation. In contrast, in CD4+ T cells from wild type mice, PPARα activation suppresses Th17 cell differentiation. Furthermore, IL-6 neutralizing antibody dose-dependently reduces the activity of STAT3 and down-regulates the protein expression of RORγt in CD4+ T cells from PPARα knockout mice but has no effect on that of wild type mice. On the other hand, in isolated CD4+ T cells from experimental autoimmune myocarditis (EAM) rats, PPARα agonist Fenofibrate decreased the expression of IL-17 and RORγt, increased the expression of Foxp3, while PPARα antagonist MK886 reversed these effects. Importantly, in vivo activation of PPARα ameliorates EAM by suppressing Th17 cell differentiation through reducing the expression of RORγt and phosphorylated STAT3 that are upregulated in EAM hearts. These results imply that PPARα suppresses Th17 cell differentiation through IL-6/STAT3/RORγt signaling pathway and suggest that PPARα may become a molecular target for treating autoimmune myocarditis.


Assuntos
Diferenciação Celular/genética , Miocardite/genética , PPAR alfa/genética , Células Th17/imunologia , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Modelos Animais de Doenças , Humanos , Interleucina-17/genética , Interleucina-6/genética , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Miocardite/imunologia , Miocardite/patologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética , Células Th17/metabolismo
20.
Microb Pathog ; 126: 351-356, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471433

RESUMO

Mycobacterium tuberculosis biofilms harbour drug-tolerant bacteria. Identification of drugs that inhibit biofilm formation could enable the dramatic shortening of tuberculosis treatments using standard antibiotics. Arisaema sinii Krause is used to treat pulmonary and lymphatic tuberculosis by Dong People of China. Current study was aimed to purify the active components against M. tuberculosis biofilms from Arisaema sinii extract by using bioassay-guided isolation. (E)-2-(methyl (phenyl) amino) ethyl 2-(2-hydroxyundecanamido)-7, 11-dimethyl-3-oxotetradec-4-enoate, compound 1, was identified as the active component. It could inhibit mycobacterial biofilm formation, disperse the preformed biofilms, and disrupt the mature biofilms at concentration of 4, 8, and 32 µg/ml, respectively. At the dose of 32 µg/ml, it could potentiate the bactericidal activity of isoniazid against M. tuberculosis in mature biofilms. The results of this study indicate that compound 1 might be a novel lead compound against mycobacterial biofilm formation.


Assuntos
Antituberculosos/farmacologia , Arisaema/química , Biofilmes/efeitos dos fármacos , Bioensaio/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Antituberculosos/química , Antituberculosos/isolamento & purificação , China , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Tolerância a Medicamentos , Isoniazida/farmacologia , Medicina Tradicional Chinesa , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células Vero/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa