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1.
Adv Sci (Weinh) ; 10(7): e2204643, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36638276

RESUMO

The characteristics of global prevalence and high recurrence of bladder cancer has led numerous efforts to develop new treatments. The spontaneous voiding and degradation of the chemodrug hamper the efficacy and effectiveness of intravesical chemotherapy following tumor resection. Herein, the externally thiolated hollow mesoporous silica nanoparticles (MSN-SH(E)) is fabricated to serve as a platform for improved bladder intravesical therapy. Enhanced mucoadhesive effect of the thiolated nanovector is confirmed with porcine bladder. The permeation-enhancing effect is also verified, and a fragmented distribution pattern of a tight junction protein, claudin-4, indicates the opening of tight junction. Moreover, MSN-SH(E)-associated reprogramming of M2 macrophages to M1-like phenotype is observed in vitro. The antitumor activity of the mitomycin C (MMC)-loaded nanovector (MMC@MSN-SH(E)) is more effective than that of MMC alone in both in vitro and in vivo. In addition, IHC staining is used to analyze IFN-γ, TGF-ß1, and TNF-α. These observations substantiated the significance of MMC@MSN-SH(E) in promoting anticancer activity, holding the great potential for being used in intravesical therapy for non-muscle invasive bladder cancer (NMIBC) due to its mucoadhesivity, enhanced permeation, immunomodulation, and prolonged and very efficient drug exposure.


Assuntos
Nanopartículas , Neoplasias da Bexiga Urinária , Animais , Suínos , Antibióticos Antineoplásicos , Adjuvantes Imunológicos/uso terapêutico , Dióxido de Silício , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Mitomicina/uso terapêutico
2.
Anal Bioanal Chem ; 414(18): 5595-5607, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35359181

RESUMO

Apolipoprotein E containing high-density lipoprotein (apoE-HDL) and apoE-HDL cholesterol (apoE-HDL-C) are recently recognized as potential biomarkers for coronary heart disease (CHD). We herein developed a two-stage, enzyme-assisted, dual-signal aptasensor that enables a useful electrochemical sensing platform for simultaneous determination of apoE-HDL, apoE-HDL-C, and total HDL-C presented in the sample. The detection scheme consists of two subsystems. In subsystem (I), the level of apoE-HDL is evaluated upon the binding of apoE-specific aptamer and subsequently methylene blue (MB)-labeled DNA displacement occurs on the electrode surface, resulting in electrochemical reduction of methylene blue. In subsystem (II), two kinds of cholesterol levels (apoE-HDL-C and total HDL-C) can be measured. For apoE-HDL-C, the amount of cholesterol in apoE-HDL captured by the aptamer in the first step can be further determined with the aid of surfactant, cholesterol esterase, cholesterol oxidase, and p-aminophenol-mediated electrochemical signal amplification. As for total HDL-C, the amount of cholesterol is determined by the same approach as that used for apoE-HDL-C determination, but without washing (separation). The linear dynamic range for apoE-HDL determination is from 1 to 100 mg/dL (R2 = 1.00). For cholesterol standards, the linear dynamic range is determined to be 0-250 mg/dL (R2 = 0.98). Finally, serial dilutions of purified human HDL preparations were examined using the newly developed aptasensor; the percentage of apoE-HDL-C to HDL-C was found to be ~10%, which correlated well with previously reported values. In conclusion, we successfully developed an electrochemical aptasensor that allows concurrent quantification of apoE-HDL, apoE-HDL-C, and HDL-C on the same platform, offering an efficient, convenient, and purification-free sensing strategy for predictive CHD biomarkers.


Assuntos
Apolipoproteínas E , HDL-Colesterol , Doença das Coronárias , Fatores de Risco de Doenças Cardíacas , Doença das Coronárias/diagnóstico , Humanos , Azul de Metileno
3.
J Nanobiotechnology ; 19(1): 89, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781277

RESUMO

BACKGROUND: Areas of hypoxia are often found in triple-negative breast cancer (TNBC), it is thus more difficult to treat than other types of breast cancer, and may require combination therapies. A new strategy that combined bioreductive therapy with photodynamic therapy (PDT) was developed herein to improve the efficacy of cancer treatment. Our design utilized the characteristics of protoporphyrin IX (PpIX) molecules that reacted and consumed O2 at the tumor site, which led to the production of cytotoxic reactive oxygen species (ROS). The low microenvironmental oxygen levels enabled activation of a bioreductive prodrug, tirapazamine (TPZ), to become a toxic radical. The TPZ radical not only eradicated hypoxic tumor cells, but it also promoted therapeutic efficacy of PDT. RESULTS: To achieve the co-delivery of PpIX and TPZ for advanced breast cancer therapy, thin-shell hollow mesoporous Ia3d silica nanoparticles, designated as MMT-2, was employed herein. This nanocarrier designed to target the human breast cancer cell MDA-MB-231 was functionalized with PpIX and DNA aptamer (LXL-1), and loaded with TPZ, resulting in the formation of TPZ@LXL-1-PpIX-MMT-2 nanoVector. A series of studies confirmed that our nanoVectors (TPZ@LXL-1-PpIX-MMT-2) facilitated in vitro and in vivo targeting, and significantly reduced tumor volume in a xenograft mouse model. Histological analysis also revealed that this nanoVector killed tumor cells in hypoxic regions efficiently. CONCLUSIONS: Taken together, the synergism and efficacy of this new therapeutic design was confirmed. Therefore, we concluded that this new therapeutic strategy, which exploited a complementary combination of PpIX and TPZ, functioned well in both normoxia and hypoxia, and is a promising medical procedure for effective treatment of TNBC.


Assuntos
Antineoplásicos/farmacologia , Nanopartículas/uso terapêutico , Fotoquimioterapia/métodos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Aptâmeros de Nucleotídeos , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Humanos , Camundongos , Oxigênio , Pró-Fármacos , Espécies Reativas de Oxigênio , Dióxido de Silício , Tirapazamina , Carga Tumoral , Hipóxia Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Biomed Res Int ; 2020: 6936879, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32382565

RESUMO

BACKGROUND: Grip-force performance can be affected by aging, and hand-grip weakness is associated with functional limitations of dasily living. However, using an appropriate digital hand-held dynamometer with continuous hand-grip force data collection shows age-related changes in the quality of hand-grip force control may provide more valuable information for clinical diagnoses rather than merely recording instantaneous maximal hand-grip force in frail elderly adults or people with a disability. Therefore, the purpose of this study was to indicate the construct validity of the digital MicroFET3 dynamometer with Jamar values for maximal grip-force assessments in elderly and young adults and confirmed age-related changes in the maximal and the quality of grip-force performance using the MicroFET3 dynamometer in elderly people. METHODS: Sixty-five healthy young (23.3 ± 4.5 years) and 50 elderly (69.5 ± 5.8 years) adults were recruited and asked to perform a validity test of the grip-force maximum voluntary contraction (MVC) using both the dominant and nondominant hands with a Jamar dynamometer and a MicroFET3 dynamometer. RESULTS: A strong correlation of maximal grip-force measurements was found between the MicroFET3 dynamometer and Jamar standard dynamometer for both hands in all participants (p < 0.05). Although, the results showed that a lower grip force was measured in both hands by the MicroFET3 dynamometer than with the Jamar dynamometer by 49.9%~57% (p < 0.05), but confidently conversion formulae were also developed to convert MicroFET3 dynamometer values to equivalent Jamar values for both hands. Both dynamometers indicated age-related declines in the maximum grip-force performance by 36.7%~44.3% (p < 0.05). We also found that the maximal hand-grip force values generated in both hand by the elderly adults were slower and more inconsistent than those of the young adults when using the MicroFET3 dynamometer. CONCLUSIONS: This study demonstrated that the digital MicroFET3 dynamometer has good validity when used to measure the maximal grip force of both hands, and conversion formulae were also developed to convert MicroFET3 dynamometer force values to Jamar values in both hands. Comparing with the Jamar dynamometer for measuring grip force, the MicroFET3 dynamometer not only indicated age-related declines in the maximum grip-force performance but also showed slower and more inconsistent maximal hand-grip strength generation by the elderly.


Assuntos
Envelhecimento/fisiologia , Força da Mão/fisiologia , Dinamômetro de Força Muscular , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Talanta ; 200: 450-457, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036208

RESUMO

Non enzymatic detection of NADH and H2O2 is of practical significance for both environmental and biological prospective. However, there is no simple, straight forward electrochemical sensor available for sensing of them in real samples. Addressing this challenge, we report a simple stimuli responsive aminophenol, pre-anodized screen printed carbon electrode (SPCE*/AP) based electrochemical probes for dual detection of NADH and H2O2. Aminophenol prepared and adsorbed on the electrode from aminophenylboronic acid via boronic acid deprotection with H2O2. The SPCE*/AP fabricated with this process was characterized by cyclic voltammetry (CV), scanning electron microscope (SEM), Raman spectroscopy, UV-visible spectroscopy, and X-ray photoelectron spectroscopy (XPS). Amperometric detection results showed that SPCE*/AP electrodes exhibited linearity from 50 µM to 500 µM and from 200 µM to 2 mM with a detection limit (S/N = 3) of 4.2 µM and 28.9 µM for NADH and H2O2, respectively. Excellent reproducibility and selectivity for NADH and H2O2 were observed for this electrochemical platform. In addition, the matrix effect was investigated further using the same technique to analyze NADH and H2O2 in human urine samples, human serum samples, cell culture medium (containing 10% fetal bovine serum, FBS), and environmental water samples (tap water and rain water). Also, the present sensor demonstrated promising outcomes with living cells (normal cells and cancer cells).


Assuntos
Aminofenóis/química , Técnicas Eletroquímicas , Corantes Fluorescentes/química , Peróxido de Hidrogênio/análise , NAD/análise , Células 3T3 , Animais , Carbono/química , Linhagem Celular Tumoral , Eletrodos , Humanos , Camundongos
6.
JCI Insight ; 4(7)2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944254

RESUMO

Hypoxic tumor niches are chief causes of treatment resistance and tumor recurrence. Sickle erythrocytes' (SSRBCs') intrinsic oxygen-sensing functionality empowers them to access such hypoxic niches wherein they form microaggregates that induce focal vessel closure. In search of measures to augment the scale of SSRBC-mediated tumor vaso-occlusion, we turned to the vascular disrupting agent, combretastatin A-4 (CA-4). CA-4 induces selective tumor endothelial injury, blood stasis, and hypoxia but fails to eliminate peripheral tumor foci. In this article, we show that introducing deoxygenated SSRBCs into tumor microvessels treated with CA-4 and sublethal radiation (SR) produces a massive surge of tumor vaso-occlusion and broadly propagated tumor infarctions that engulfs treatment-resistant hypoxic niches and eradicates established lung tumors. Tumor regression was histologically corroborated by significant treatment effect. Treated tumors displayed disseminated microvessels occluded by tightly packed SSRBCs along with widely distributed pimidazole-positive hypoxic tumor cells. Humanized HbS-knockin mice (SSKI) but not HbA-knockin mice (AAKI) showed a similar treatment response underscoring SSRBCs as the paramount tumoricidal effectors. Thus, CA-4-SR-remodeled tumor vessels license SSRBCs to produce an unprecedented surge of tumor vaso-occlusion and infarction that envelops treatment-resistant tumor niches resulting in complete tumor regression. Strategically deployed, these innovative tools constitute a major conceptual advance with compelling translational potential.


Assuntos
Anemia Falciforme/sangue , Antineoplásicos Fitogênicos/administração & dosagem , Eritrócitos Anormais/transplante , Neoplasias Pulmonares/terapia , Recidiva Local de Neoplasia/terapia , Animais , Adesão Celular , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Terapia Combinada/métodos , Feminino , Técnicas de Introdução de Genes , Hemoglobina Falciforme/genética , Humanos , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Transgênicos , Microvasos/citologia , Microvasos/efeitos dos fármacos , Microvasos/patologia , Recidiva Local de Neoplasia/irrigação sanguínea , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estilbenos/administração & dosagem , Transplante Heterólogo/métodos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Biol Blood Marrow Transplant ; 24(8): 1554-1562, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29684562

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) can be curative for patients with sickle cell disease (SCD). However, morbidity associated with myeloablative conditioning and graft-versus-host disease has limited its utility. To this end, autologous HSCT for SCD using lentiviral gene-modified bone marrow (BM) or peripheral blood stem cells has been undertaken, although toxicities of fully ablative conditioning with busulfan and incomplete engraftment have been encountered. Treosulfan, a busulfan analog with a low extramedullary toxicity profile, has been used successfully as part of a myeloablative conditioning regimen in the allogeneic setting in SCD. To further minimize toxicity of conditioning, noncytotoxic monoclonal antibodies that clear stem cells from the marrow niche, such as anti-c-Kit (ACK2), have been considered. Using a murine model of SCD, we sought to determine whether nonmyeloablative conditioning followed by transplantation with syngeneic BM cells could ameliorate the disease phenotype. Treosulfan and ACK2, in a dose-dependent manner, decreased BM cellularity and induced cytopenia in SCD mice. Conditioning with treosulfan alone at nonmyeloablative dosing (3.6 g/kg), followed by transplantation with syngeneic BM donor cells, permitted long-term mixed-donor chimerism. Level of chimerism correlated with improvement in hematologic parameters, normalization of urine osmolality, and improvement in liver and spleen pathology. Addition of ACK2 to treosulfan conditioning did not enhance engraftment. Our data suggests that pretransplant conditioning with treosulfan alone may allow sufficient erythroid engraftment to reverse manifestations of SCD, with clinical application as a preparative regimen in SCD patients undergoing gene-modified autologous HSCT.


Assuntos
Anemia Falciforme/terapia , Transplante de Medula Óssea/métodos , Bussulfano/análogos & derivados , Condicionamento Pré-Transplante/métodos , Animais , Anticorpos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Bussulfano/uso terapêutico , Modelos Animais de Doenças , Sobrevivência de Enxerto , Camundongos , Proteínas Proto-Oncogênicas c-kit/imunologia , Resultado do Tratamento
8.
Nutrients ; 9(9)2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-28846663

RESUMO

Luobuma (Apocynum venetum L. (AVL)) is a popular beverage in Asia and has been reportedly to be associated with the bioactivities such as cardiotonic, diuretic, antioxidative, and antihypertensive. However, its biofunction as chemoprevention activity is seldom addressed. Herein, we aimed to characterize the anti-androgen-insensitive-prostate-cancer (anti-AIPC) bioactive compounds of Luobuma, and to investigate the associated molecular mechanisms. Activity-guided-fractionation (antioxidative activity and cell survivability) of Luobuma ethanolic extracts was performed to isolate and characterize the major bioactive compounds using Ultra Performance Liquid Chromatography (UPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR). Plant sterols (lupeol, stigamasterol and ß-sitosterol) and polyphenolics (isorhamnetin, kaempferol, and quercetin) were identified. Lupeol, a triterpene found in the fraction (F8) eluted by 10% ethyl acetate/90% hexane and accounted for 19.3% (w/w) of F8, inhibited the proliferation of PC3 cells. Both lupeol and F8 induced G2/M arrest, inhibition of ß-catenin signaling, regulation of apoptotic signal molecules (cytochrome c, Bcl-2, P53, and caspase 3 and 8), and suppression DNA repair enzyme expression (Uracil-DNA glycosylase (UNG)). To our knowledge, our study is the first report that lupeol inhibited the expression of UNG to elicit the cytotoxicity against androgen-insensitive-prostate-cancer cells. Collectively, Luobuma, which contains several antitumor bioactive compounds, holds the potential to be a dietary chemopreventive agent for prostate cancer.


Assuntos
Anticarcinógenos/metabolismo , Apocynum/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Neoplasias de Próstata Resistentes à Castração/prevenção & controle , Anticarcinógenos/química , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Suplementos Nutricionais , Etnofarmacologia , Fase G2 , Humanos , Masculino , Estrutura Molecular , Proteínas de Neoplasias/metabolismo , Triterpenos Pentacíclicos/análise , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/farmacologia , Extratos Vegetais/análise , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Taiwan , Uracila-DNA Glicosidase/antagonistas & inibidores , Uracila-DNA Glicosidase/metabolismo , Via de Sinalização Wnt , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismo
9.
Am J Hematol ; 92(10): 981-988, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28646491

RESUMO

Sickle erythrocytes' (SSRBCs) unique physical adaptation to hypoxic conditions renders them able to home to hypoxic tumor niches in vivo, shut down tumor blood flow and induce tumoricidal responses. SSRBCs are also useful vehicles for transport of encapsulated drugs and oncolytic virus into hypoxic tumors with enhanced anti-tumor effects. In search of additional modes for arming sickle cells with cytotoxics, we turned to a lentiviral ß-globin vector with optimized Locus Control Region/ß-globin coding region/promoter/enhancers. We partially replaced the ß-globin coding region of this vector with genes encoding T cell cytolytics, perforin and granzyme or immune modulating superantigens SEG and SEI. These modified vectors efficiently transduced Sca+ ckit- Lin- hematopoietic stem cells (HSCs) from humanized sickle cell knockin mice. Irradiated mice reconstituted with these HSCs displayed robust expression of transgenic RNAs and proteins in host sickle cells that was sustained for more than 10 months. SSRBCs from reconstituted mice harboring SEG/SEI transgenes induced robust proliferation and a prototypical superantigen-induced cytokine reaction when exposed to human CD4+/CD8+ cells. The ß-globin lentiviral vector therefore produces a high level of functional, erythroid-specific immune modulators and cytotoxics that circulate without toxicity. Coupled with their unique ability to target and occlude hypoxic tumor vessels these armed SSRBCs constitute a potentially useful tool for treatment of solid tumors.


Assuntos
Anemia Falciforme , Citotoxicidade Imunológica , Eritrócitos Anormais/imunologia , Neoplasias Experimentais/imunologia , Neovascularização Patológica/imunologia , Globinas beta/genética , Anemia Falciforme/sangue , Animais , Citotoxicidade Imunológica/genética , Sistemas de Liberação de Medicamentos , Eritrócitos Anormais/metabolismo , Eritrócitos Anormais/transplante , Técnicas de Introdução de Genes , Vetores Genéticos , Transplante de Células-Tronco Hematopoéticas , Hipóxia , Lentivirus/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/terapia , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia
10.
Stem Cells Transl Med ; 6(4): 1168-1177, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28233474

RESUMO

Recruitment of neutrophils and monocytes/macrophages to the site of vascular injury is mediated by binding of chemoattractants to interleukin (IL) 8 receptors RA and RB (IL8RA/B) C-C chemokine receptors (CCR) 2 and 5 expressed on neutrophil and monocyte/macrophage membranes. Endothelial cells (ECs) derived from rat-induced pluripotent stem cells (RiPS) were transduced with adenovirus containing cDNA of IL8RA/B and/or CCR2/5. We hypothesized that RiPS-ECs overexpressing IL8RA/B (RiPS-IL8RA/B-ECs), CCR2/5 (RiPS-CCR2/5-ECs), or both receptors (RiPS-IL8RA/B+CCR2/5-ECs) will inhibit inflammatory responses and neointima formation in balloon-injured rat carotid artery. Twelve-week-old male Sprague-Dawley rats underwent balloon injury of the right carotid artery and intravenous infusion of (a) saline vehicle, (b) control RiPS-Null-ECs (ECs transduced with empty virus), (c) RiPS-IL8RA/B-ECs, (d) RiPS-CCR2/5-ECs, or (e) RiPS-IL8RA/B+CCR2/5-ECs. Inflammatory mediator expression and leukocyte infiltration were measured in injured and uninjured arteries at 24 hours postinjury by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, respectively. Neointima formation was assessed at 14 days postinjury. RiPS-ECs expressing the IL8RA/B or CCR2/5 homing device targeted the injured arteries and decreased injury-induced inflammatory cytokine expression, neutrophil/macrophage infiltration, and neointima formation. Transfused RiPS-ECs overexpressing IL8RA/B and/or CCR2/5 prevented inflammatory responses and neointima formation after vascular injury. Targeted delivery of iPS-ECs with a homing device to inflammatory mediators in injured arteries provides a novel strategy for the treatment of cardiovascular diseases. Stem Cells Translational Medicine 2017;6:1168-1177.


Assuntos
Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Receptores CCR2/metabolismo , Receptores CCR5/metabolismo , Receptores de Interleucina-8/metabolismo , Lesões do Sistema Vascular/metabolismo , Lesões do Sistema Vascular/terapia , Animais , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco Pluripotentes Induzidas/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Masculino , Neutrófilos/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Biosens Bioelectron ; 87: 142-149, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27543858

RESUMO

Tyramine (4-hydroxyphenethylamine), which is a monoamine metabolized by monoamine oxidase (MAO), exists widely in plants, animals, fermented foods, and salted foods. The incidence of hypertension, or "cheese effect", which is associated with a large dietary intake of tyramine while taking MAO inhibitors has been reported; therefore, the measurement of tyramine is an urgent concern. Herein, an efficient approach that integrates a molecular imprinting polymer for solid phase extraction (MISPE) technique with a sensitive electrochemical sensing platform (SPCE/PEDOT: PSS/AuNP/1-m-4-MP) for the quantification of tyramine is presented. Enhanced electrode conductivity was achieved sequentially by constructing a conductive polymer (PEDOT: PSS) on a screen-printed carbon electrode (SPCE), followed by electrodeposition with gold nanoparticles (AuNPs) and, finally, by modification with positively charged 1-methyl-4-mercaptopyridine (1-m-4-MP) using an Au-S bond. Tyramine was isolated selectively and pre-concentrated by the MISPE technique; electroanalysis that used differential pulse voltammetry (DPV) in NaOH (0.1M, pH 13) was conducted successively. Experimental parameters (such as modes of electrode modification, ratio of PEDOT: PSS, pH of electrolyte, time required for AuNP deposition, and 1-m-4-MP concentrations) that were associated with optimal detection conditions were evaluated also. We obtained a linear concentration range (5-100nM, R2=0.9939) with LOD and sensitivity at 2.31nM, and 3.11µAnM-1cm-2, respectively. The applicability of our technique was demonstrated by analyzing tyramine in spiked serum and milk. The feature of our newly developed analytical methods that coupled sample pre-treatment (sample clean-up and pre-concentration) with sensitive detection makes it a promising tool for quantifying of tyramine.


Assuntos
Técnicas Eletroquímicas/métodos , Leite/química , Impressão Molecular/métodos , Poliestirenos/química , Extração em Fase Sólida/métodos , Tiofenos/química , Tiramina/análise , Tiramina/sangue , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Carbono/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Ouro/química , Humanos , Nanopartículas Metálicas/química , Impressão Molecular/instrumentação , Piridinas/química , Extração em Fase Sólida/instrumentação
12.
Artigo em Inglês | MEDLINE | ID: mdl-28029125

RESUMO

In this study, we developed curcumin-encapsulated hyaluronic acid-polylactide nanoparticles (CEHPNPs) to be used for liver fibrosis amelioration. CD44, the hyaluronic acid (HA) receptor, is upregulated on the surface of cancer cells and on activated hepatic stellate cells (aHSCs) rather than normal cells. CEHPNPs could bind to CD44 and be internalized effectively through endocytosis to release curcumin, a poor water-soluble liver protective agent. Thus, CEHPNPs were potentially not only improving drug efficiency, but also targeting aHSCs. HA and polylactide (PLA) were crosslinked by adipic acid dihydrazide (ADH). The synthesis of HA-PLA was monitored by Fourier-transform infrared (FTIR) and Nuclear Magnetic Resonance (NMR). The average particle size was approximately 60-70 nm as determined by dynamic light scattering (DLS) and scanning electron microscope (SEM). Zeta potential was around -30 mV, which suggested a good stability of the particles. This drug delivery system induced significant aHSC cell death without affecting quiescent HSCs, hepatic epithelial, and parenchymal cells. This system reduced drug dosage without sacrificing therapeutic efficacy. The cytotoxicity IC50 (inhibitory concentration at 50%) value of CEHPNPs was approximately 1/30 to that of the free drug treated group in vitro. Additionally, the therapeutic effects of CEHPNPs were as effective as the group treated with the same curcumin dose intensity in vivo. CEHPNPs significantly reduced serum aspartate transaminase/alanine transaminase (ALT/AST) significantly, and attenuated tissue collagen production and cell proliferation as revealed by liver biopsy. Conclusively, the advantages of superior biosafety and satisfactory therapeutic effect mean that CEHPNPs hold great potential for treating hepatic fibrosis.


Assuntos
Curcumina/administração & dosagem , Sistemas de Liberação de Medicamentos , Ácido Hialurônico/administração & dosagem , Cirrose Hepática/tratamento farmacológico , Nanopartículas/administração & dosagem , Poliésteres/administração & dosagem , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Curcumina/química , Curcumina/uso terapêutico , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/química , Ácido Hialurônico/uso terapêutico , Cirrose Hepática/sangue , Cirrose Hepática/induzido quimicamente , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Poliésteres/química , Poliésteres/uso terapêutico , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Ratos , Tioacetamida
13.
PLoS Negl Trop Dis ; 10(9): e0004974, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27622634

RESUMO

The coagulation system provides a primitive but effective defense against hemorrhage. Soluble fibrinogen (Fg) monomers, composed of α, ß and γ chains, are recruited to provide structural support for the formation of a hemostatic plug. Fg binds to platelets and is processed into a cross-linked fibrin polymer by the enzymatic clotting factors, thrombin and Factor XIII (FXIII). The newly formed fibrin-platelet clot can act as barrier to protect against pathogens from entering the bloodstream. Further, injuries caused by bacterial infections can be confined to the initial wound site. Many pathogenic bacteria have Fg-binding adhesins that can circumvent the coagulation pathway and allow the bacteria to sidestep containment. Fg expression is upregulated during lung infection providing an attachment surface for bacteria with the ability to produce Fg-binding adhesins. Fg binding by leptospira might play a crucial factor in Leptospira-associated pulmonary hemorrhage, the main factor contributing to lethality in severe cases of leptospirosis. The 12th domain of Leptospira immunoglobulin-like protein B (LigB12), a leptospiral adhesin, interacts with the C-terminus of FgαC (FgαCC). In this study, the binding site for LigB12 was mapped to the final 23 amino acids at the C-terminal end of FgαCC (FgαCC8). The association of FgαCC8 with LigB12 (ELISA, KD = 0.76 µM; SPR, KD = 0.96 µM) was reduced by mutations of both charged residues (R608, R611 and H614 from FgαCC8; D1061 from LigB12) and hydrophobic residues (I613 from FgαCC8; F1054 and A1065 from LigB12). Additionally, LigB12 bound strongly to FXIII and also inhibited fibrin formation, suggesting that LigB can disrupt coagulation by suppressing FXIII activity. Here, the detailed binding mechanism of a leptospiral adhesin to a host hemostatic factor is characterized for the first time and should provide better insight into the pathogenesis of leptospirosis.


Assuntos
Antígenos de Bactérias/metabolismo , Fator XIII/metabolismo , Fibrinogênio/metabolismo , Interações Hospedeiro-Patógeno , Leptospira/patogenicidade , Leptospirose/microbiologia , Fragmentos de Peptídeos/metabolismo , Adesinas Bacterianas/metabolismo , Sítios de Ligação , Coagulação Sanguínea , Humanos , Ligação Proteica , Trombina/metabolismo
14.
Sci Rep ; 6: 30422, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27460639

RESUMO

CRISPR/Cas enhanced correction of the sickle cell disease (SCD) genetic defect in patient-specific induced Pluripotent Stem Cells (iPSCs) provides a potential gene therapy for this debilitating disease. An advantage of this approach is that corrected iPSCs that are free of off-target modifications can be identified before differentiating the cells into hematopoietic progenitors for transplantation. In order for this approach to be practical, iPSC generation must be rapid and efficient. Therefore, we developed a novel helper-dependent adenovirus/Epstein-Barr virus (HDAd/EBV) hybrid reprogramming vector, rCLAE-R6, that delivers six reprogramming factors episomally. HDAd/EBV transduction of keratinocytes from SCD patients resulted in footprint-free iPSCs with high efficiency. Subsequently, the sickle mutation was corrected by delivering CRISPR/Cas9 with adenovirus followed by nucleoporation with a 70 nt single-stranded oligodeoxynucleotide (ssODN) correction template. Correction efficiencies of up to 67.9% (ß(A)/[ß(S)+ß(A)]) were obtained. Whole-genome sequencing (WGS) of corrected iPSC lines demonstrated no CRISPR/Cas modifications in 1467 potential off-target sites and no modifications in tumor suppressor genes or other genes associated with pathologies. These results demonstrate that adenoviral delivery of reprogramming factors and CRISPR/Cas provides a rapid and efficient method of deriving gene-corrected, patient-specific iPSCs for therapeutic applications.


Assuntos
Adenoviridae/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/terapia , Sistemas CRISPR-Cas/genética , Terapia Genética , Vetores Genéticos/metabolismo , Vírus Auxiliares/metabolismo , Sequência de Bases , Linhagem Celular , Herpesvirus Humano 4 , Homozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo
15.
Front Oncol ; 6: 166, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27458571

RESUMO

Insights from the study of cancer resistance in animals have led to the discovery of novel anticancer pathways and opened new venues for cancer prevention and treatment. Sickle cells (SSRBCs) from subjects with homozygous sickle cell anemia (SCA) have been shown to target hypoxic tumor niches, induce diffuse vaso-occlusion, and potentiate a tumoricidal response in a heme- and oxidant-dependent manner. These findings spawned the hypothesis that SSRBCs and the vasculopathic microenvironment of subjects with SCA might be inimical to tumor outgrowth and thereby constitute a natural antitumor defense. We therefore implanted the B16F10 melanoma into humanized hemoglobin SS knockin mice which exhibit the hematologic and vasculopathic sequelae of human SCA. Over the 31-day observation period, hemoglobin SS mice showed no significant melanoma outgrowth. By contrast, 68-100% of melanomas implanted in background and hemoglobin AA knockin control mice reached the tumor growth end point (p < 0.0001). SS knockin mice also exhibited established markers of underlying vasculopathy, e.g., chronic hemolysis (anemia, reticulocytosis) and vascular inflammation (leukocytosis) that differed significantly from all control groups. Genetic differences or normal AA gene knockin do not explain the impaired tumor outgrowth in SS knockin mice. These data point instead to the chronic pro-oxidative vasculopathic network in these mice as the predominant cause. In related studies, we demonstrate the ability of the sickle cell component of this system to function as a therapeutic vehicle in potentiating the oncolytic/vasculopathic effect of RNA reovirus. Sickle cells were shown to efficiently adsorb and transfer the virus to melanoma cells where it induced apoptosis even in the presence of anti-reovirus neutralizing antibodies. In vivo, SSRBCs along with their viral cargo rapidly targeted the tumor and initiated a tumoricidal response exceeding that of free virus and similarly loaded normal RBCs without toxicity. Collectively, these data unveil two hitherto unrecognized findings: hemoglobin SS knockin mice appear to present a natural barrier to melanoma tumorigenesis while SSRBCs demonstrate therapeutic function as a vehicle for enhancing the oncolytic effect of free reovirus against established melanoma.

16.
PLoS One ; 10(4): e0121298, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25849560

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the third most common cause of cancer-related death worldwide. Sorafenib is the only drug for patients with advanced-stage hepatocellular carcinoma (HCC) that has been shown to confer a survival benefit to patients with HCC; however, it has many side effects. Thus, alternate therapeutic strategies with improved safety and therapeutic efficacy for the management of HCC should be developed. METHODS AND FINDINGS: We demonstrate that an extract of Graptopetalum paraguayense (GP) down-regulated the expression levels of several onco-proteins, including AURKA, AURKB, and FLJ10540, in HCC cells. To isolate the active components in the GP extracts, we prepared extracts fractions and assessed their effects on the expression of onco-proteins in HCC cells. The fraction designated HH-F3 was enriched in active ingredients, exhibited cytotoxic effects, and suppressed the expression of the onco-proteins in HCC cells. The structure of the main active compound in HH-F3 was found to be similar to that of the proanthocyanidin compounds derived from Rhodiola rosea. In addition, a distinct new compound rich in 3, 4, 5-trihydroxy benzylic moieties was identified in the HH-F3 preparations. Mechanistic studies indicated that HH-F3 induced apoptosis in HCC cells by promoting the loss of mitochondrial membrane potential and the production of reactive oxygen species. HH-F3 also enhanced PTEN expression and decreased AKT phosphorylation at Ser473 in a concentration-dependent manner in HCC cells. Moreover combination of GP or HH-F3 and sorafenib synergistically inhibits the proliferation of Huh7 cells. The treatment of a rat model with diethylnitrosamine (DEN)-induced liver cancer with extracts of GP and HH-F3 decreased hepatic collagen contents and inhibited tumor growth. CONCLUSIONS: These results indicate that GP extracts and HH-F3 can protect the liver by suppressing tumor growth; consequently, these compounds could be considered for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Experimentais , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Saxifragaceae/química , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Neoplasias/biossíntese , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Extratos Vegetais/química , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
17.
PLoS One ; 10(3): e0120713, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25816210

RESUMO

Gallic acid (3, 4, 5-trihydroxybenzoic acid, GA), a natural phenolic acid widely found in gallnuts, tea leaves and various fruits, possesses several bioactivities against inflammation, oxidation, and carcinogenicity. The beneficial effect of GA on the reduction of animal hepatofibrosis has been indicated due to its antioxidative property. However, the cytotoxicity of GA autoxidation causing cell death has also been reported. Herein, we postulated that GA might target activated hepatic stellate cells (aHSCs), the cell type responsible for hepatofibrosis, to mitigate the process of fibrosis. The molecular cytotoxic mechanisms that GA exerted on aHSCs were then analyzed. The results indicated that GA elicited aHSC programmed cell death through TNF-α-mediated necroptosis. GA induced significant oxidative stress through the suppression of catalase activity and the depletion of glutathione (GSH). Elevated oxidative stress triggered the production of TNF-α facilitating the undergoing of necroptosis through the up-regulation of key necroptotic regulatory proteins TRADD and receptor-interacting protein 3 (RIP3), and the inactivation of caspase-8. Calmodulin and calpain-1 activation were engaged, which promoted subsequent lysosomal membrane permeabilization (LMP). The TNF-α antagonist (SPD-304) and the RIP1 inhibitor (necrostatin-1, Nec-1) confirmed GA-induced TNFR1-mediated necroptosis. The inhibition of RIP1 by Nec-1 diverted the cell death from necroptosis to apoptosis, as the activation of caspase 3 and the increase of cytochrome c. Collectively, this is the first report indicating that GA induces TNF signaling-triggered necroptosis in aHSCs, which may offer an alternative strategy for the amelioration of liver fibrosis.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Gálico/farmacologia , Células Estreladas do Fígado/patologia , Necrose/induzido quimicamente , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Western Blotting , Caspases/metabolismo , Ciclo Celular , Proliferação de Células , Células Cultivadas , Cromanos/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Indóis/farmacologia , Peroxidação de Lipídeos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Biomaterials ; 42: 30-41, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25542791

RESUMO

A combination of various therapeutic approaches has emerged as a promising strategy for cancer treatment. A safe and competent nano-delivery system is thus in urgent demand to facilitate the simultaneous transport of various therapeutic agents to cancer cells and a tumor region to achieve synergistic effect. Gold nanoparticles (GNPs) and mesoporous silica nanoparticle (MSNs) were fabricated herein as potential candidates for drug delivery. Serving as gatekeepers, GNPs (5 nm in diameter) were attached onto the amino-functionalized MSNs (denoted as NMSNs) via a relatively weak gold-nitrogen bonding. The resulting nanohybrids (denoted as GCMSNs) were uptaken by cells, and the detachment of GNPs and subsequent intracellular drug release from NMSNs were achieved by competitive binding of intracellular glutathione to GNPs. In addition to the function of gatekeeping, GNPs also play another role as the oxidative stress elicitor. Our in vitro studies revealed that GCMSNs induced higher oxidative stress in lung cancer cells (A549) than in normal cells (3T3-L1). This growth inhibitory effect found in the cancer cells was likely induced by mitochondria dysfunction originated from the GCMSN-induced, oxidative stress-triggered mitochondria-mediated autophagy. The redox-responsive nanohybrids were further loaded with camptothecin and the intensified synergistic therapeutic effects were observed associated with combined chemotherapy and oxidative stress strategy. The results clearly demonstrate that such unique nanohybrids hold great promise for selective and effective cancer treatments.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Autofagia/efeitos dos fármacos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Células 3T3-L1 , Animais , Camptotecina/farmacologia , Linhagem Celular Tumoral , Metabolismo Energético/efeitos dos fármacos , Glutationa/farmacologia , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Nanopartículas/ultraestrutura , Neoplasias/patologia , Oxirredução/efeitos dos fármacos , Porosidade , Dióxido de Silício/química , Ensaios Antitumorais Modelo de Xenoenxerto
19.
ACS Appl Mater Interfaces ; 6(7): 5168-74, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24598813

RESUMO

The spike-piece-structured Ni(OH)2 multilayer nanoplate arrays on nickel foams are directly synthesized by a facile hydrothermal method at 160 °C for 4 h. A possible mechanism for the growth of those nanostructures is proposed based on the experimental results. It is discovered that the surface of nickel foams could affect the orientation of the Ni(OH)2 nanoplates. This unique multilayer nanoplate array structure significantly enhances the electroactive surface areas of Ni(OH)2, leading to shorter ion-diffusion paths, and displays a capacity of 2.83 F/cm(2) at a current density of 6 mA/cm(2) in 0-0.48 V versus the saturated calomel electrode. It also exhibits a good cycling performance, with 51.5% of its initial capacity after about 3000 cycles at a large current density of 24 mA/cm(2). The present results may provide a new strategy for the synthesis and application of nickel-foam-based composites for energy storage.

20.
Artigo em Inglês | MEDLINE | ID: mdl-24204395

RESUMO

Destruxin B, isolated from entomopathogenic fungus Metarhizium anisopliae, is one of the cyclodepsipeptides with insecticidal and anticancer activities. In this study, destruxin B was extracted and purified by ion-exchange chromatography, silica gel chromatography, and semipreparative high-performance liquid chromatography. The potential anticancer effects and molecular mechanisms of destruxin B in human nonsmall cell lung cancer cell lines were characterized. Our results showed that destruxin B induced apoptotic cell death in A549 cells. This event was accompanied by the activation of caspase-2, -3, and -9. Moreover, destruxin B increased the expression level of proapoptotic molecule, PUMA, while decreased antiapoptotic molecule Mcl-1. Additionally, the translocation of Bax from cytosol to mitochondrial membrane was observed upon destruxin B treatment. Knockdown of Bax by shRNA effectively attenuated destruxin-B-triggered apoptosis in A549 cells. Interestingly, similar toxic effects and underlying mechanisms including caspase activation, upregulation of PUMA, and downregulation of Mcl-1 were also observed in a p53-null lung cancer H1299 cell line upon destruxin B treatment. Taken together, our findings suggest that destruxin-B-induced apoptosis in human nonsmall cell lung cancer cells is via a Bcl-2 family-dependent mitochondrial pathway.

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