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1.
Biosens Bioelectron ; 226: 115141, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796307

RESUMO

To date, it is still a challenge for high-performance photoelectrochemical (PEC) assay of low-abundance adenosine deaminase (ADA) in fundamental research and clinical diagnosis. Herein, phosphate-functionalized Pt/TiO2 (termed PO43-/Pt/TiO2) was prepared as ideal photoactive material to develop a split-typed PEC aptasensor for detection of ADA activity, coupled by a Ru(bpy)32+ sensitization strategy. We critically studied the effects of the PO43- and Ru(bpy)32+ on the detection signals, and discussed the signal-amplified mechanism. Specifically, hairpin-structured adenosine (AD) aptamer was splited into single chain via ADA-induced catalytic reaction, and subsequently hybridized with complementary DNA (cDNA, initially coating on magnetic beads). The in-situ formed double-stranded DNA (dsDNA) was further intercalated by more Ru(bpy)32+ to amplify the photocurrents. The resultant PEC biosensor showed a broader linear range of 0.05-100 U L-1 and a lower limit of detection (0.019 U L-1), which can fill the blank for analysis of ADA activity. This research would provide some valuable insights for building advanced PEC aptasensors in ADA-related research and clinical diagnosis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Adenosina Desaminase , Fosfatos , Titânio , Técnicas Eletroquímicas , Limite de Detecção
2.
Biosens Bioelectron ; 203: 114048, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121445

RESUMO

Enzyme-mediated signal amplification strategies have gained substantial attention in photoelectrochemical (PEC) biosensing, while natural enzyme on the photoelectrode inevitably obstructs the interfacial electron transfer, in turn deteriorating the photocurrent responses. Herein, Au nanoparticles and Cu2+-modified boron nitride nanosheets (AuNPs/Cu2+-BNNS) behaved as nanozyme to achieve remarkable magnification in the PEC signals from a novel signal-off aptasensor for ultra-sensitive assay of telomerase (TE) activity based on Ag2S/Ag nanoparticles decorated ZnIn2S4/C3N4 Z-scheme heterostructures (termed as Ag2S/Ag/ZnIn2S4/C3N4, synthesized by hydrothermal treatment). Specifically, telomerase primer sequences (TS) were extended by TE in the presence of deoxyribonucleoside triphosphates (dNTPs), which was directly bond with the thiol modified complementary DNA (cDNA), achieving efficient linkage with the nanozyme via Au-S bond. The immobilized nanoenzyme catalyzed the oxidation between 4-chloro-1-naphthol (4-CN) and H2O2 to generate insoluble precipitation on the photo-electrode. By virtue of the inhibited PEC signals with the TE-enabled TS extension, an aptasensor for assay of TE activity was developed, showing the wide linear range of 50-5×105 cell mL-1 and a low detection limit of 19 cell mL-1. This work provides some valuable guidelines for developing advanced nanozyme-based PEC bioanalysis of diverse cancer cells.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Telomerase , Boro , Compostos de Boro , Técnicas Eletroquímicas , Ouro/química , Peróxido de Hidrogênio , Limite de Detecção , Nanopartículas Metálicas/química , Prata
3.
Dis Model Mech ; 15(3)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35023548

RESUMO

Parkinson's disease (PD) is associated with α-synuclein-based Lewy body pathology, which has been difficult to observe in conventional two-dimensional (2D) cell culture and even in animal models. We herein aimed to develop a three-dimensional (3D) cellular model of PD to recapitulate the α-synuclein pathologies. All-trans-retinoic acid-differentiated human SH-SY5Y cells and Matrigel were optimized for 3D construction. The 3D cultured cells displayed higher tyrosine hydroxylase expression than 2D cells and improved dopaminergic-like phenotypes, as suggested by RNA-sequencing analyses. Multiple forms of α-synuclein, including monomer, and low- and high-molecular mass oligomers, were differentially present in the 2D and 3D cells, but mostly remained unchanged upon N-methyl-4-phenyl pyridine or rotenone treatment. Phosphorylated α-synuclein was accumulated, and detergent-insoluble α-synuclein fraction was observed, in the neurotoxin-treated 3D cells. Importantly, Lewy body-like inclusions were captured in the 3D system, including proteinase K-resistant α-synuclein aggregates, ubiquitin aggregation, and ß-amyloid and ß-sheet protein deposition. The study provides a unique and convenient 3D model of PD that recapitulates critical α-synuclein pathologies and should be useful in multiple PD-associated applications.


Assuntos
Doença de Parkinson , Linhagem Celular Tumoral , Colágeno , Combinação de Medicamentos , Humanos , Laminina/metabolismo , Corpos de Lewy/metabolismo , Doença de Parkinson/patologia , Proteoglicanas , alfa-Sinucleína/metabolismo
4.
Mikrochim Acta ; 189(2): 56, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006398

RESUMO

Carbon-coated cadmium sulfide rose-like nanostructures (CdS@C NRs) were prepared via a facile solvothermal approach and used as the photoelectrochemical (PEC) sensing platform for the integration of functional biomolecules. Based on this, a novel "signal-off" PEC aptasensor mediated by enzymatic amplification was proposed for the sensitive and selective detection of 17ß-estradiol (E2). In the presence of E2, alkaline phosphatase-modified aptamer (ALP-apta) were released from the electrode surface through the specific recognition with E2, which caused the negative effect on PEC response due to the decrease of ascorbic acid (AA) produced by the ALP in situ enzymatic catalysis. The developed PEC aptasensor for detection of E2 exhibited a wide linear range of 1.0-250 nM, with the low detection limit of 0.37 nM. This work provides novel insight into the design of potential phoelectroactive materials and the application of signal amplification strategy in environmental analysis field.


Assuntos
Compostos de Cádmio/química , Carbono , Enzimas/metabolismo , Estradiol/química , Nanoestruturas/química , Processos Fotoquímicos , Sulfetos/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Enzimas/química , Microscopia Eletrônica de Varredura
5.
J Neuroinflammation ; 18(1): 47, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602262

RESUMO

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are commonly used new-generation drugs for depression. Depressive symptoms are thought to be closely related to neuroinflammation. In this study, we used up-to-date protocols of culture and stimulation and aimed to understand how astrocytes respond to the antidepressants. METHODS: Primary astrocytes were isolated and cultured using neurobasal-based serum-free medium. The cells were treated with a cytokine mixture comprising complement component 1q, tumor necrosis factor α, and interleukin 1α with or without pretreatments of antidepressants. Cell viability, phenotypes, inflammatory responses, and the underlying mechanisms were analyzed. RESULTS: All the SSRIs, including paroxetine, fluoxetine, sertraline, citalopram, and fluvoxamine, show a visible cytotoxicity within the range of applied doses, and a paradoxical effect on astrocytic inflammatory responses as manifested by the promotion of inducible nitric oxide synthase (iNOS) and/or nitric oxide (NO) and the inhibition of interleukin 6 (IL-6) and/or interleukin 1ß (IL-1ß). The SNRI venlafaxine was the least toxic to astrocytes and inhibited the production of IL-6 and IL-1ß but with no impact on iNOS and NO. All the drugs had no regulation on the polarization of astrocytic A1 and A2 types. Mechanisms associated with the antidepressants in astrocytic inflammation route via inhibition of JNK1 activation and STAT3 basal activity. CONCLUSIONS: The study demonstrated that the antidepressants possess differential cytotoxicity to astrocytes and function differently, also paradoxically for the SSRIs, to astrocytic inflammation. Our results provide novel pieces into understanding the differential efficacy and tolerability of the antidepressants in treating patients in the context of astrocytes.


Assuntos
Antidepressivos/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Animais Recém-Nascidos , Antidepressivos/toxicidade , Astrócitos/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Ratos , Ratos Sprague-Dawley , Inibidores Seletivos de Recaptação de Serotonina/toxicidade
6.
Mol Neurobiol ; 58(6): 2620-2633, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33483902

RESUMO

Aberrant DNA methylation is closely associated with the pathogenesis of Parkinson's disease (PD). DNA methyltransferases (DNMTs) are the enzymes for establishment and maintenance of DNA methylation patterns. It has not been clearly defined how DNMTs respond in PD and what mechanisms are associated. Models of PD were established by treatment of five different neurotoxins in cells and intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice. Plasma samples of PD patients were also used. Western blot, real-time PCR, immunostaining, and/or luciferase reporter were employed. DNA methylation was analyzed by the bisulfite sequencing analysis. Protein expression of DNMT1, but not of DNMT3A and DNMT3B, was reduced in the cellular and mouse models of PD. Paradoxically, mRNA levels of DNMT1 were increased in these models. After ruling out the possibility of protein degradation, we screened a set of miRNAs that potentially targeted DNMT1 3'-UTR by luciferase reporters and expression abundancies. miR-17 was identified for further investigation with miR-19a of low expression as a parallel comparison. Although exogenous transfection of either miR-17 or miR-19a mimics could inhibit DNMT1 expression, results of miRNA inhibitors showed that miR-17, but not miR-19a, endogenously regulated DNMT1 and the subsequent DNA methylation. Furthermore, levels of miR-17 were elevated in the neurotoxin-induced PD models and the plasma of PD patients. This study demonstrates that the miR-17-mediated DNMT1 downregulation underlies the aberrant DNA methylation in PD. Our results provide a link bridging environmental insults and epigenetic changes and implicate miR-17 in therapeutical modulation of DNA methylation in PD.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/metabolismo , MicroRNAs/metabolismo , Doença de Parkinson/enzimologia , Doença de Parkinson/genética , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Modelos Biológicos , Neurotoxinas/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
7.
World J Gastrointest Oncol ; 12(10): 1167-1176, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33133384

RESUMO

BACKGROUND: Numerous studies have demonstrated that human epididymis protein 4 (HE4) is overexpressed in various malignant tissues including ovarian, endometrial, lung, breast, pancreatic, and gastric cancers. However, no study has examined the diagnostic impact of HE4 in patient with esophageal squamous cell carcinoma (ESCC) until now. AIM: To analyze the value of four serum tumor markers for the diagnosis of ESCC, and examine the associations of serum levels of HE4 with ESCC patients' clinicopathological characteristics. METHODS: The case group consisted of 80 ESCC patients, which were compared to a control group of 56 patients with benign esophageal disease. Serum levels of HE4, carcinoma embryonic antigen (CEA), alpha fetal protein, and carbohydrate antigen 19-9 (CA19-9) were detected by ELISA. The associations of serum HE4 levels with ESCC patients' clinicopathological characteristics such as gender, tumor location, and pathological stage were also examined after operation. RESULTS: The result of ELISA showed that serum HE4 level was significantly higher in the patients with ESCC than in the controls, and the staining intensity was inversely correlated with the pathological T and N stages. Serum HE4 levels had a sensitivity of 66.2% and specificity of 78.6% when the cutoff value was set at 3.9 ng/mL. Moreover, the combined HE4 and CA19-9 increased the sensitivity to 83.33%, and interestingly, the combination of HE4 with CEA led to the most powerful sensitivity of 87.5%. Furthermore, A positive correlation was observed between HE4 serum levels and pathological T and N stages (P = 0.0002 and 0.0017, respectively), but there was no correlation between HE4 serum levels and ESCC patient gender (P = 0.4395) or tumor location (P = 0.6777). CONCLUSION: The results of this study suggest that detection of serum HE4 levels may be useful in auxiliary diagnosis and evaluation of the progression of ESCC.

8.
J Neuroinflammation ; 17(1): 50, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024542

RESUMO

BACKGROUND: Astrocytes are the most abundant glial cells in a brain that mediate inflammatory responses and provide trophic support for neurons. We have previously disclosed that paroxetine, a common selective serotonin reuptake inhibitor, ameliorates LPS-induced microglia activation. However, it remains elusive for the role of paroxetine in astrocytic responses. METHODS: Isolated primary astrocytes were pretreated with paroxetine and stimulated with different stimuli, lipopolysaccharide (LPS) or microglia conditioned medium pre-activated with LPS (M/Lps). Inflammatory and neurotrophic responses, underlying mechanisms and the impact on neuronal survival were assessed. RESULTS: Paroxetine had no impact on LPS-stimulated iNOS, TNF-α, and IL-1ß expression, but inhibited M/Lps-induced TNF-α and IL-1ß expression in primary astrocytes. Paroxetine suppressed M/Lps- but not LPS-induced activation of NF-κB and had no impact on the activation of MAPKs and STAT3. Incubation with the resulted astrocyte conditioned media caused no change in the viability of SH-SY5Y cells. BDNF and MANF mRNA expressions were upregulated by M/Lps and paroxetine, respectively. However, M/Lps- or LPS-induced extracellular releases of NO, TNF-α, and/or BDNF in astrocytes were in minor amount compared to those by microglia. CONCLUSIONS: Paroxetine ameliorates the reactive microglia-mediated inflammatory responses in astrocytes partially via inhibition of the NF-κB pathway but has no impact on LPS-stimulated astrocyte activation. While the effects of paroxetine on secondary astrocytic responses are not robust compared to its effect on the innate immune responses of microglia, the results together may implicate a therapeutic potential of paroxetine against neuroinflammation-associated neurological disorders such as Parkinson's disease.


Assuntos
Astrócitos/efeitos dos fármacos , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Microglia/efeitos dos fármacos , Paroxetina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Astrócitos/metabolismo , Linhagem Celular , Humanos , Interleucina-1beta/metabolismo , Camundongos , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
J Nutr ; 149(12): 2110-2119, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504723

RESUMO

BACKGROUND: Selenium is prioritized to the brain mainly for selenoprotein expression. Selenoprotein T (SELENOT) protects dopaminergic, postmitotic neurons in a mouse model of Parkinson's disease (PD). OBJECTIVE: We hypothesized a proliferative role of SELENOT in neural cells. METHODS: To assess SELENOT status in PD, sedated male C57BL/6 mice at 10-12 wk of age were injected with 6-hydroxydopamine in neurons, and human peripheral blood mononuclear cells were isolated from 9 healthy subjects (56% men, 68-y-old) and 11 subjects with PD (64% men, 63-y-old). Dopaminergic neural progenitor-like SK-N-SH cells with transient SELENOT overexpression or knockdown were maintained in the presence or absence of the antioxidant N-acetyl-l-cysteine and the calcium channel blocker nimodipine. Cell cycle, proliferation, and signaling parameters were determined by immunoblotting, qPCR, and flow cytometry. RESULTS: SELENOT mRNA abundance was increased (P < 0.05) in SK-N-SH cells treated with 1-methyl-4-phenylpyridinium iodide (3.5-fold) and peripheral blood mononuclear cells from PD patients (1.6-fold). Likewise, SELENOT was expressed in tyrosine hydroxylase-positive dopaminergic neurons of 6-hydroxydopamine-injected mice. Knockdown of SELENOT in SK-N-SH cells suppressed (54%; P < 0.05) 5-ethynyl-2'-deoxyuridine incorporation but induced (17-47%; P < 0.05) annexin V-positive cells, CASPASE-3 cleavage, and G1/S cell cycle arrest. SELENOT knockdown and overexpression increased (88-120%; P < 0.05) and reduced (37-42%; P < 0.05) both forkhead box O3 and p27, but reduced (51%; P < 0.05) and increased (1.2-fold; P < 0.05) cyclin-dependent kinase 4 protein abundance, respectively. These protein changes were diminished by nimodipine or N-acetyl-l-cysteine treatment (24 h) at steady-state levels. While the N-acetyl-l-cysteine treatment did not influence the reduction in the amount of calcium (13%; P < 0.05) by SELENOT knockdown, the nimodipine treatment reversed the decreased amount of reactive oxygen species (33%; P < 0.05) by SELENOT overexpression. CONCLUSIONS: These cellular and mouse data link SELENOT to neural proliferation, expanding our understanding of selenium protection in PD.


Assuntos
Proliferação de Células/fisiologia , Fase G1/fisiologia , Doença de Parkinson/patologia , Fase S/fisiologia , Selenoproteínas/fisiologia , Idoso , Animais , Cálcio/metabolismo , Linhagem Celular , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Doença de Parkinson/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
10.
Biol Trace Elem Res ; 188(1): 189-195, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30229511

RESUMO

The thioredoxin-like (Rdx) family proteins contain four selenoproteins (selenoprotein H, SELENOH; selenoprotein T, SELENOT; selenoprotein V, SELENOV; selenoprotein W, SELENOW) and a nonselenoprotein Rdx12. They share a CxxU or a CxxC (C, cysteine; x, any amino acid; U, selenocysteine) motif and a stretch of eGxFEI(V) sequence. From the evolutionary perspective, SELENOW and SELENOV are clustered together and SELENOH and SELENOT are in another branch. Selenoproteins in the Rdx family exhibit tissue- and organelle-specific distribution and are differentially influenced in response to selenium deficiency. While SELENOH is nucleus-exclusive, SELENOT resides mainly in endoplasmic reticulum and SELENOW in cytosol. SELENOV is expressed essentially only in the testes with unknown cellular localization. SELENOH and SELENOW are more sensitive than SELENOT and SELENOV to selenium deficiency. While physiological functions of the Rdx family of selenoproteins are not fully understand, results from animal models demonstrated that (1) brain-specific SELENOT knockout mice are susceptible to 1-methyl-4-phenylpyridinium-induced Parkinson's disease in association with redox imbalance and (2) adult zebrafishes with heterozygous SELENOH knockout are prone to dimethylbenzanthracene-induced tumorigenesis together with increased DNA damage and oxidative stress. Further animal and human studies are needed to fully understand physiological roles of the Rdx family of selenoproteins in redox regulation, genome maintenance, aging, and age-related degeneration.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Selênio/deficiência , Selênio/metabolismo , Selenoproteínas/fisiologia , Tiorredoxinas/fisiologia , Animais , Humanos , Selenoproteínas/genética , Tiorredoxinas/genética
11.
Int Immunopharmacol ; 50: 14-21, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28622577

RESUMO

Hyperoside (quercetin-3-O-ß-d-galactoside) is an active compound isolated from herbs. Neuroinflammation is a key mechanism involved in neurodegenerative disorders including Parkinson's disease. In this study, we aimed to investigate the potentiality of hyperoside in inhibiting microglia-mediated neuroinflammation. BV2 microglial cells were pretreated with hyperoside and stimulated with lipopolysaccharide (LPS). The results showed that hyperoside significantly inhibited LPS-induced production of nitric oxide and pro-inflammatory cytokines including IL-1ß and TNF-α, as well as the expression of inducible nitric oxide synthase. Similar results were observed in primary microglial cells isolated from neonatal mice. Analyses in MAPK and NFκB signaling combined with specific inhibitors suggested that hyperoside attenuated the LPS-induced inflammatory responses via p38 and NFκB pathways. Furthermore, hyperoside suppressed reactive microglia-mediated neurotoxicity as evidenced by conditioned media culture, but had no direct impact on MPP+-induced toxicity in SH-SY5Y neuroblastoma cells. Collectively, our data suggest that hyperoside may serve as a protective agent by alleviating microglia activation in disorders such as Parkinson's disease.


Assuntos
Anti-Inflamatórios/farmacologia , Microglia/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Inflamação Neurogênica/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Quercetina/análogos & derivados , Animais , Linhagem Celular Tumoral , Interleucina-1beta/metabolismo , Lipopolissacarídeos/imunologia , Camundongos , Microglia/imunologia , Neuroblastoma/imunologia , Doenças Neurodegenerativas/imunologia , Inflamação Neurogênica/imunologia , Óxido Nítrico/metabolismo , Doença de Parkinson/imunologia , Quercetina/farmacologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Sci Rep ; 6: 36669, 2016 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-27827408

RESUMO

Brain iron levels in patients of Parkinson's disease (PD) are usually measured in postmortem samples or by MRI imaging including R2* and SWI. In this study we performed a meta-analysis to understand PD-associated iron changes in various brain regions, and to evaluate the accuracy of MRI detections comparing with postmortem results. Databases including Medline, Web of Science, CENTRAL and Embase were searched up to 19th November 2015. Ten brain regions were identified for analysis based on data extracted from thirty-three-articles. An increase in iron levels in substantia nigra of PD patients by postmortem, R2* or SWI measurements was observed. The postmortem and SWI measurements also suggested significant iron accumulation in putamen. Increased iron deposition was found in red nucleus as determined by both R2* and SWI, whereas no data were available in postmortem samples. Based on SWI, iron levels were increased significantly in the nucleus caudatus and globus pallidus. Of note, the analysis might be biased towards advanced disease and that the precise stage at which regions become involved could not be ascertained. Our analysis provides an overview of iron deposition in multiple brain regions of PD patients, and a comparison of outcomes from different methods detecting levels of iron.


Assuntos
Encéfalo , Ferro/metabolismo , Imageamento por Ressonância Magnética , Doença de Parkinson , Mudanças Depois da Morte , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo
13.
Oncotarget ; 7(28): 43731-43745, 2016 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-27248323

RESUMO

Myofibroblastic transformation, characterized by upregulation of α-smooth muscle actin in response to profibrotic agents such as TGF-ß1, is considered as a major event leading to fibrosis. The mechanistic basis linking myofibroblast differentiation to idiopathic pulmonary fibrosis and the disease treatment remain elusive. In this study, we studied roles of MAPK, Notch, and reactive oxygen species (ROS) during the differentiation of IMR-90 lung fibroblasts at basal level and induced by TGF-ß1. Our results demonstrated that ROS-dependent activation of p38, JNK1/2 and Notch3 promoted basal and TGF-ß1-induced differentiation and expression of extracellular matrix proteins. In stark contrast, ERK1/2 was suppressed by ROS and exhibited an inhibitory effect on the differentiation but showed a weak promotion on the expression of extracellular matrix proteins. TGF-ß1-induced Notch3 expression depended on p38 and JNK1/2. Interestingly, Notch3 was also downstream of ERK1/2, suggesting a complex role of ERK1/2 in lung function. Our results suggest a novel ROS-mediated shift of dominance from the inhibitory ERK1/2 to the stimulatory p38, JNK1/2 and Notch3 during the pathological progression of IPF. Thus, targeting ERK1/2 signaling for activation and p38, JNK1/2 and Notch3 for inhibition may be of clinical potential against lung fibrosis.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/metabolismo , Miofibroblastos/patologia , Receptor Notch3/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Fibroblastos/metabolismo , Humanos , Fibrose Pulmonar Idiopática/patologia , Masculino , Camundongos Endogâmicos C57BL , Miofibroblastos/metabolismo , Oxirredução , Transdução de Sinais
14.
Oncotarget ; 7(21): 30855-66, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27102435

RESUMO

Notch3 receptor is expressed in a variety of cancers and the excised active intracellular domain (N3ICD) initiates its signaling cascade. N-acetylcysteine (NAC) as an antioxidant has been implicated in cancer prevention and therapy. In this study, we demonstrated a negative regulation of Notch3 by NAC in cancer cells. HeLa cells treated with NAC exhibited a time- and concentration-dependent decrease in Notch3 levels and its downstream effectors Hes1 and HRT1 in a manner independent of f-secretase or glutathione. In contrast, NAC did not affect protein levels of Notch1, the full length Notch3 precursor, or ectopically expressed N3ICD. Although SOD, catalase and NAC suppressed reactive oxygen species in HeLa cells, the first two antioxidants did not impact on Notch3 levels. While the mRNA expression of Notch3 was not altered by NAC, functional inhibition of lysosome, but not proteasome, blocked the NAC-dependent reduction of Notch3 levels. Furthermore, results from Notch3 silencing and N3ICD overexpression demonstrated that NAC prevented malignant phenotypes through down-regulation of Notch3 protein in multiple cancer cells. In summary, NAC reduces Notch3 levels through lysosome-dependent protein degradation, thereby negatively regulates Notch3 malignant signaling in cancer cells. These results implicate a novel NAC treatment in sensitizing Notch3-expressing tumors.


Assuntos
Acetilcisteína/farmacologia , Lisossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor Notch3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetilcisteína/uso terapêutico , Secretases da Proteína Precursora do Amiloide/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Catalase/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação para Baixo , Técnicas de Silenciamento de Genes , Glutationa/metabolismo , Células HeLa , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios Proteicos , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Receptor Notch1/metabolismo , Receptor Notch3/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição HES-1/metabolismo
15.
IUBMB Life ; 68(1): 5-12, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26614639

RESUMO

Selenium is an essential metalloid required for the expression of selenoproteins. While cells are constantly challenged by clastogens of endogenous and exogenous origins, genome integrity is maintained by direct repair of DNA damage, redox balance, and epigenetic regulation. To date, only five selenoproteins are experimentally demonstrated to reside in nucleus, exclusively or partially, including selenoprotein H, methionine-R-sulfoxide reductase 1, glutathione peroxidase-4, thioredoxin reductase-1, and thioredoxin glutathione reductase. All these five selenoproteins have demonstrated or potential roles in redox regulation and genome maintenance. Selenoprotein H is known to transactivate the expression of a couple of genes against oxidative stress. The thioredoxin reductase-1b isoform delivers estrogen receptor-α and -ß to the nucleus. Nuclear glutathione peroxidase-4 epigenetically and globally inhibits gene expression through the maintenance of chromatin compactness in testes. Continued studies on how these and additional nuclear selenoproteins regulate genome stability will have profound impact on advancing our understanding in selenium regulation of optimal health. © 2015 IUBMB Life, 68(1):5-12, 2016.


Assuntos
Núcleo Celular/enzimologia , Epigênese Genética , Selenoproteínas/fisiologia , Sequência de Aminoácidos , Animais , Expressão Gênica , Instabilidade Genômica , Humanos , Dados de Sequência Molecular , Sinais de Localização Nuclear , Oxirredução , Estresse Oxidativo , Selenoproteínas/química
16.
Physiol Rev ; 96(1): 307-64, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26681794

RESUMO

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from aerobic metabolism, as a result of accidental electron leakage as well as regulated enzymatic processes. Because ROS/RNS can induce oxidative injury and act in redox signaling, enzymes metabolizing them will inherently promote either health or disease, depending on the physiological context. It is thus misleading to consider conventionally called antioxidant enzymes to be largely, if not exclusively, health protective. Because such a notion is nonetheless common, we herein attempt to rationalize why this simplistic view should be avoided. First we give an updated summary of physiological phenotypes triggered in mouse models of overexpression or knockout of major antioxidant enzymes. Subsequently, we focus on a series of striking cases that demonstrate "paradoxical" outcomes, i.e., increased fitness upon deletion of antioxidant enzymes or disease triggered by their overexpression. We elaborate mechanisms by which these phenotypes are mediated via chemical, biological, and metabolic interactions of the antioxidant enzymes with their substrates, downstream events, and cellular context. Furthermore, we propose that novel treatments of antioxidant enzyme-related human diseases may be enabled by deliberate targeting of dual roles of the pertaining enzymes. We also discuss the potential of "antioxidant" nutrients and phytochemicals, via regulating the expression or function of antioxidant enzymes, in preventing, treating, or aggravating chronic diseases. We conclude that "paradoxical" roles of antioxidant enzymes in physiology, health, and disease derive from sophisticated molecular mechanisms of redox biology and metabolic homeostasis. Simply viewing antioxidant enzymes as always being beneficial is not only conceptually misleading but also clinically hazardous if such notions underpin medical treatment protocols based on modulation of redox pathways.


Assuntos
Antioxidantes/metabolismo , Enzimas/metabolismo , Nível de Saúde , Estresse Oxidativo , Animais , Modelos Animais de Doenças , Indução Enzimática , Repressão Enzimática , Enzimas/biossíntese , Enzimas/genética , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Humanos , Camundongos Transgênicos , Estado Nutricional , Oxirredução , Fenótipo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco
17.
Artigo em Inglês | MEDLINE | ID: mdl-26557149

RESUMO

Huangqi Sanxian decoction (HQSXD) is routinely used for the treatment of osteoporosis in the Chinese traditional healthcare system. However, the targets and mechanism underlying the effect of HQSXD on osteoporosis have not been documented. In the present study, seropharmacology and proteomic approaches (two-dimensional gel electrophoresis combined with mass spectrometry) were used to investigate the effects and possible target proteins of HQSXD on osteoblast. We found that HQSXD-treated rat serum significantly enhanced osteoblast proliferation, differentiation, and mineralization. In HQSXD-S-treated osteoblasts, there were increases in the expression of N-formyl peptide receptor 2 and heparan sulfate (glucosamine) 3-O-sulfotransferase 3A1 and reduction in the expression of alpha-spectrin, prohibitin, and transcription elongation factor B (SIII), polypeptide 1. The identified proteins are associated with cell proliferation, differentiation, signal transcription, and cell growth. These findings might provide valuable insights into the mechanism of antiosteoporotic effect affected by HQSXD treatment in osteoblasts.

18.
Biopreserv Biobank ; 13(1): 31-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25686045

RESUMO

Genome-wide sequencing in glioma samples provides comprehensive insights into oncogenesis and malignant transformation. Several distinct biomarkers have been proven to have clinical significance and are being widely applied in routine clinical practice. Standard sample processing lays the foundation for successful molecular testing. In this study, we found intraoperative neuronavigation ensured higher tumor purity during sample collection, and an automated device helped improve DNA quality and increased yields. These two technologies are beneficial for glioma tissue bank construction and provide for accurate molecular testing during routine clinical practice.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Neuronavegação/métodos , Análise de Sequência de DNA/métodos , Bancos de Tecidos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , DNA de Neoplasias/análise , Glioma/genética , Glioma/cirurgia , Humanos , Controle de Qualidade , Manejo de Espécimes/métodos
19.
J Immunol Res ; 2014: 131494, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25126583

RESUMO

A2B5+ glioblastoma (GBM) cells have glioma stem-like cell (GSC) properties that are crucial to chemotherapy resistance and GBM relapse. T-cell-based antigens derived from A2B5+ GBM cells provide important information for immunotherapy. Here, we show that HEAT repeat containing 1 (HEATR1) expression in GBM tissues was significantly higher than that in control brain tissues. Furthermore, HEATR1 expression in A2B5+ U87 cells was higher than that in A2B5-U87 cells (P = 0.016). Six peptides of HEATR1 presented by HLA-A∗02 were selected for testing of their ability to induce T-cell responses in patients with GBM. When peripheral blood mononuclear cells from healthy donors (n = 6) and patients with glioma (n = 33) were stimulated with the peptide mixture, eight patients with malignant gliomas had positive reactivity with a significantly increased number of responding T-cells. The peptides HEATR(1682-690), HEATR(11126-1134), and HEATR(1757-765) had high affinity for binding to HLA-A∗02:01 and a strong capacity to induce CTL response. CTLs against HEATR1 peptides were capable of recognizing and lysing GBM cells and GSCs. These data are the first to demonstrate that HEATR1 could induce specific CTL responses targeting both GBM cells and GSCs, implicating that HEATR1 peptide-based immunotherapy could be a novel promising strategy for treating patients with GBM.


Assuntos
Glioma/genética , Glioma/imunologia , Proteínas de Ligação a RNA/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Adolescente , Adulto , Idoso , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Feminino , Expressão Gênica , Glioma/metabolismo , Glioma/patologia , Antígenos HLA-A/imunologia , Antígenos HLA-A/metabolismo , Humanos , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor , Gradação de Tumores , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica/imunologia , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Adulto Jovem
20.
Neurol Sci ; 35(7): 1115-20, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24514918

RESUMO

Despite dramatic advances in cancer therapy, the overall prognosis of glioblastoma (GBM) remains dismal. Nuclear factor kappa-B (NF-κB) has been previously demonstrated to be constitutively activated in glioblastoma, and it was suggested as a potential therapeutic target. Glycyrrhizic acid (GA) has been proved to have cytotoxic effects in many cancer cell lines. However, its role in glioblastoma has not yet been addressed. Therefore, this study aimed to investigate the effects of GA on human glioblastoma U251 cell line. The effects of GA on proliferation of U251 cells were measured by CCK-8 assay and plate colony-forming test. Cellular apoptosis was detected by Hoechst 33258 fluorescent staining and flow cytometry with annexin V-FITC/PI dual staining. The expression of nuclear p65 protein, the active subunit of NF-κB, was determined by Western blot and immunofluorescence. Our results demonstrated that the survival rate and colony formation of U251 cells significantly decreased in a time- and dose-dependent manner after GA addition, and the apoptotic ratio of GA-treated groups was significantly higher than that of control groups. Furthermore, the expression of NF-κB-p65 in the nucleus was remarkably reduced after GA treatment. In conclusion, our findings suggest that GA treatment can confer inhibitory effects on human glioblastoma U251 cell line including inhibiting proliferation and inducing apoptosis, which is possibly related to the NF-κB mediated pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Proliferação de Células/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Glioblastoma/patologia , Humanos , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos
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