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1.
Biosens Bioelectron ; 257: 116319, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38669845

RESUMO

This research presents a selective and sensitive electrochemical biosensor for the detection of the mesenchymal-epithelial transition factor (c-MET). The biosensing is based on a modification of the SPCE (screen-printed carbon electrode) with the electrospun nanofiber containing eudragit (EU), hydroxypropyl methylcellulose (HPMC), and Zeolite imidazolate frameworks (ZIF-8) nanoparticles. EU/HPMC/ZIF-8 nanofibers have presented a high capability of electron transfer, and more active surface area than bare SPCE due to synergistic effects between EU, HPMC, and ZIF-8. On the other hand, EU/HPMC nanofibers provided high porosity, flexible structures, high specific surface area, and good mechanical strength. The presence of ZIF-8 nanoparticles improved the immobilization of anti-c-MET on the modified SPCE and also resulted in increasing the conductivity. By c-MET incubation on the modified SPCE, c-MET was connected to anti-c-MET, and consequently the electrochemical signal of [Fe(CN)6]3-/4- as the anion redox probe was reduced. In order to investigate the structural and morphological characteristics and elemental composition of electrospun nanofibers, various characterization methods including FE-SEM, XRD, FTIR, and EDS were used. Under optimum conditions with a working potential range -0.3-0.6 V (vs. Ag/AgCl), linear range (LR), correlation coefficient (R2), sensitivity, and limit of detection (LOD) were acquired at 100 fg/mL-100 ng/mL, 0.9985, 53.28 µA/cm2.dec, and 1.28 fg/mL, respectively. Moreover, the mentioned biosensor was investigated in a human plasma sample to determine c-MET and showed ideal results including reproducibility, stability, and good selectivity against other proteins.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Técnicas Eletroquímicas , Nanofibras , Proteínas Proto-Oncogênicas c-met , Humanos , Biomarcadores Tumorais/sangue , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Imidazóis , Limite de Detecção , Estruturas Metalorgânicas/química , Nanofibras/química , Nanopartículas/química , Neoplasias/sangue , Proteínas Proto-Oncogênicas c-met/sangue , Zeolitas/química
2.
Bioimpacts ; 13(5): 405-413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736340

RESUMO

Introduction: The inhibition of vascularization into tumor stroma as well as dynamic cell growth is the center of attention. Here, we aimed to examine the role of vandetanib on angiogenesis capacity of breast cancer stem cell (CSCs). Methods: MDA-MB-231 cells were exposed to different doses of vandetanib and survival rate was monitored. Stimulatory effects of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and epidermal growth factor (EGF) were evaluated in vandetanib-treated MDA-MB-231 cells. In vitro tubulogenesis capacity was studied on the Matrigel surface. The synergistic effects of vandetanib on cell survival were also assessed after PI3K and/or Wnt3a inhibition. Vascular endothelial (VE)-cadherin, matrix metalloproteinase-2 (MMP-2), -9, Wnt3a, and p-Akt/Akt ratio were measured using western blotting. Results: Vandetanib reduced survival rate in a dose-dependent manner (P<0.05). Proliferative effects associated with VEGF, FGF, and EGF were blunted in these cells pre-exposed to vandetanib (P<0.05). The microcirculation pattern's triple-negative breast cancer (TNBC) was suppressed by 1, 5 µM of vandetanib (P<0.05). Hence 1, 5 µM of vandetanib potentially decreased the population of CD24- cells. 1 and 5 µM of vandetanib inhibited cell proliferation by blocking PI3K and Wnt3a pathways and decreased the p-Akt/Akt ratio, Wnta3 protein levels (P<0.05). 1 and 5 µM vandetanib combined with PI3K inhibitor diminished metastatic markers including, MMP-2, and MMP-9. The concurrent treatment (PI3K, inhibitor+ 1, 5 µM vandetanib) also considerably reduced epithelial-mesenchymal transition (EMT) markers such as VE-cadherin (P<0.05). Conclusion: Vandetanib suppressed vasculogenic mimicry (VM) networking through blunting stemness properties, coincided with suppression of VE-cadherin in CSCs.

3.
Sci Rep ; 13(1): 16163, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37758805

RESUMO

Alzheimer's disease (AD) is a progressive brain disorder characterized by the ongoing decline of brain functions. Studies have revealed the detrimental effects of hyperphosphorylated tau (p-tau) protein fibrils in AD pathogenesis, highlighting the importance of this factor in the early-stage detection of AD conditions. We designed an electrochemical immunosensor for quantitative detection of the cis conformation of the p-tau protein (cis-p-tau) employing platinum nanoparticles (Pt NPs) supported on zeolitic imidazolate frameworks (ZIF) for modifying the glassy carbon electrode (GCE) surface. Under optimum conditions, the immunosensor selectively and sensitively detected cis-p-tau within the broad linear range of 1 fg mL-1 to 10 ng mL-1 and the low limit of detection (LOD) of 1 fg mL-1 with desired reproducibility and stability. Furthermore, the fabricated immunosensor's performance was examined for the cis-p-tau analysis in the serum of AD patients, indicating its accuracy and feasibility for real-sample analysis. Notably, this is the first application of Pt@ZIF-8 nanocomposite in fabricating a valid immunosensor for selective cis-p-tau detection, even in the presence of trans-p-tau. It is worth mentioning that the enzyme-linked immunosorbent assay (ELISA) reference technique is not able to evaluate pico- or femtomolar concentrations of cis-p-tau, making the fabricated immunosensor superior for early-stage measurement and screening of AD.


Assuntos
Doença de Alzheimer , Técnicas Biossensoriais , Nanopartículas Metálicas , Nanocompostos , Zeolitas , Humanos , Doença de Alzheimer/diagnóstico , Proteínas tau , Zeolitas/química , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Imunoensaio , Platina/química , Nanocompostos/química , Técnicas Eletroquímicas , Limite de Detecção , Ouro/química
4.
Mikrochim Acta ; 190(10): 418, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770707

RESUMO

An electrochemical immunosensing platform was developed for the detection of receptor tyrosine kinase-orphan receptor-2 (ROR2) at a glassy carbon electrode (GCE) modified with the electrospun nanofiber containing polyvinylpyrrolidone (PVP), soy, and Au nanoparticles (AuNPs). The PVP/soy/AuNP nanofiber exhibited good electrochemical behavior due to synergistic effects between PVP, soy, and AuNPs. The PVP/soy in the modified film provided good mechanical strength, high porosity, flexible structures, and high specific surface area. On the other hand, the presence of AuNPs effectively improved conductivity, as well as the immobilization of anti-ROR2 on the modified GCE, leading to enhanced sensitivity. Various characterization approaches such as FE-SEM, FTIR, and EDS were used for investigating the morphological and structural features, and the elemental composition. The designed immunosensor performance was investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). Under optimum conditions with a working potential range from -0.2 to 0.6 V (vs. SCE), sensitivity, linear range (LR), limit of detection (LOD), and correlation coefficient (R2) were acquired at 122.26 µA/cm2 dec, 0.01-1000 pg/mL, 3.39 fg/mL, and 0.9974, respectively. Furthermore, the determination of ROR2 in human plasma samples using the designed immunosensing platform was examined and exhibited satisfactory results including good selectivity against other proteins, reproducibility, and cyclic stability.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanofibras , Humanos , Ouro/química , Povidona , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes , Imunoensaio , Carbono , Proteínas Tirosina Quinases
5.
Talanta ; 265: 124844, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37352780

RESUMO

A novel electrochemical immunosensor was developed for ultrasensitive determination of the hormone insulin-like growth factor 1 (IGF-1) based on immobilization of a specific monoclonal antibody on the electrospun nanofibers of Polyacrylonitrile (PAN)/Zein-reduced graphene oxide (rGO) nanoparticle. The nanofibers deposited on glassy carbon electrode (GCE) showed good electrochemical behaviors with synergistic effects between PAN, Zein, and rGO. PAN/Zein nanofibers were used due to flexibility, high porosity, good mechanical strength, high specific surface area, and flexible structures, while rGO nanoparticles were used to improve the detection sensitivity and anti-IGF-1 immobilizing. Different characterization techniques were applied consisting of FE-SEM, FT-IR, and EDS for the investigation of morphological features and nanofiber size. The redox reactions of [Fe(CN)6]4-/3- on the modified electrode surface were probed for studying the immobilization and determination processes, using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Under optimal conditions, LOD (limit of detection) and LOQ (limit of quantification) were obtained as 55.72 fg/mL and 185.73 fg/mL respectively, and sensitivity was acquired 136.29 µA/cm2.dec. Moreover, a wide linear range was obtained ranging from 1 pg/mL to 10 ng/mL for IGF-1. Furthermore, the proposed method was applied for the analysis of IGF-1 in several human plasma samples with acceptable results, and it also exhibited high selectivity, stability, and reproducibility.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanofibras , Zeína , Humanos , Fator de Crescimento Insulin-Like I , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Imunoensaio/métodos , Grafite/química , Eletrodos , Nanopartículas Metálicas/química
6.
J Biomater Sci Polym Ed ; 34(5): 695-714, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36745508

RESUMO

Due to a lack of sufficient blood supply and unique physicochemical properties, the treatment of injured cartilage is laborious and needs an efficient strategy. Unfortunately, most of the current therapeutic approaches are, but not completely, unable to restore the function of injured cartilage. Tissue engineering-based modalities are an alternative option to reconstruct the injured tissue. Considering the unique structure and consistency of cartilage tissue (osteochondral junction), it is mandatory to apply distinct biomaterials with unique properties slightly different from scaffolds used for soft tissues. PCL is extensively used for the fabrication of fine therapeutic scaffolds to accelerate the restorative process. Thermosensitive PCL hydrogels with distinct chemical compositions have paved the way for sophisticated cartilage regeneration. This review aimed to collect recent findings regarding the application of PCL in hydrogels blended with natural, synthetic materials in the context of cartilage healing.


Assuntos
Hidrogéis , Engenharia Tecidual , Hidrogéis/química , Cartilagem , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Alicerces Teciduais/química
7.
Mikrochim Acta ; 190(3): 90, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36786882

RESUMO

A green, environmentally friendly protocol was developed for ultrasensitive and highly specific recognition of prostate-specific antigen (PSA) based on the ECL effect of luminol supported by chitosan-silver nanoparticles (CS/AgNPs) nanocomposites. The transducing surface was fabricated through two consecutive electrodeposition steps of gold nanoparticles (AuNPs) and chitosan (CS)-AgNPs-luminol electrochemiluminophore onto the glassy carbon electrode. In addition to an appropriate desirable biocompatibility, the electrochemical synthesis presents low-cost preparation and ultrafast determination opportunity. AgNPs play a linking role to attach luminol, as an ECL agent to the CS support via donor-acceptor bonds between Ag atoms with NH groups of luminol and CS. Also, AgNPs can amplify the ECL intensity as a consequence of their excellent specific surface area and conductivity. To enhance the performance of the nanobiosensor, AuNPs were also used due to their high-specific surface area and excellent affinity toward amine groups of CS. Based on this high-performance analysis strategy, ultrasensitive screening of PSA was attained with a desirable limit of detection of 0.6 ng mL-1 and a broad linear range between 1 pg mL-1 and 10 ng⋅mL-1 (R2=0.994). Approximately, the same results were recorded for the analysis of the unprocessed serum samples of patients with prostate cancer at different stages. This research provided significant insight into electrografting methods to construct ECL transducers for clinical monitoring of PSA and other tumor biomarkers in the clinical setting.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Humanos , Masculino , Quitosana/química , Ouro/química , Medições Luminescentes/métodos , Luminol/química , Nanopartículas Metálicas/química , Nanocompostos/química , Antígeno Prostático Específico , Prata , Técnicas Eletroquímicas
8.
Biosensors (Basel) ; 12(10)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36290911

RESUMO

For the first time, a novel aptamer was designed and utilized for the selective detection of rivaroxaban (RIV) using the integration of bioinformatics with biosensing technology. The selected aptamer with the sequence 5'-TAG GGA AGA GAA GGA CAT ATG ATG ACT CAC AAC TGG ACG AAC GTA CTT ATC CCC CCC AAT CAC TAG TGA ATT-3' displayed a high binding affinity to RIV and had an efficient ability to discriminate RIV from similar molecular structures. A novel label-free electrochemical aptasensor was designed and fabricated through the conjugation of a thiolated aptamer with Au nanoparticles (Au-NPs). Then, the aptasensor was successfully applied for the quantitative determination of RIV in human plasma and exhaled breath condensate (EBC) samples with limits of detection (LODs) of 14.08 and 6.03 nM, respectively. These valuable results provide ample evidence of the green electrogeneration of AuNPs on the surface of electrodes and their interaction with loaded aptamers (based on Au-S binding) towards the sensitive and selective monitoring of RIV in human plasma and EBC samples. This bio-assay is an alternative approach for the clinical analysis of RIV and has improved specificity and affinity. As far as we know, this is the first time that an electrochemical aptasensor has been verified for the recognition of RIV and that allows for the easy, fast, and precise screening of RIV in biological samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Ouro/química , Aptâmeros de Nucleotídeos/química , Rivaroxabana , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Limite de Detecção , Eletrodos
9.
J Tissue Eng Regen Med ; 16(7): 605-620, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35511799

RESUMO

Recently, tissue engineering and regenerative medicine have received significant attention with outstanding advances. The main scope of this technology is to recover the damaged tissues and organs or to maintain and improve their function. One of the essential fields in tissue engineering is scaffold designing and construction, playing an integral role in damaged tissues reconstruction and repair. However, premature ovarian failure (POF) is a disorder causing many medical and psychological problems in women. POF treatment using tissue engineering and various scaffold has recently made tremendous and promising progress. Due to the importance of the subject, we have summarized the recently examined scaffolds in the treatment of POF in this review.


Assuntos
Insuficiência Ovariana Primária , Feminino , Humanos , Insuficiência Ovariana Primária/etiologia , Insuficiência Ovariana Primária/terapia , Medicina Regenerativa , Engenharia Tecidual
10.
Molecules ; 27(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35056745

RESUMO

Human Tau protein is the most reliable biomarker for the prediction of Alzheimer's disease (AD). However, the assay to detect low concentrations of tau protein in serum is a great challenge for the early diagnosis of AD. This paper reports an electrochemiluminescence (ECL) immunosensor for Tau protein in serum samples. Gold nanostars (AuNSs) decorated on carbon nitride nanosheets (AuNS@g-CN nanostructure) show highly strong and stable ECL activity compared to pristine CN nanosheets due to the electrocatalytic and surface plasmon effects of AuNSs. As a result of the strong electromagnetic field at branches, AuNSs showed a better ECL enhancement effect than their spherical counterpart. For the fabrication of a specific immunosensor, immobilized AuNSs were functionalized with a monoclonal antibody specific for Tau protein. In the presence of Tau protein, the ECL intensity of the immunosensor decreased considerably. Under the optimal conditions, this ECL based immunosensor exhibits a dynamic linear range from 0.1 to 100 ng mL-1 with a low limit of detection of 0.034 ng mL-1. The LOD is less than the Tau level in human serum; thus, this study provides a useful method for the determination of Tau. The fabricated ECL immunosensor was successfully applied to the detection of Tau, the biomarker in serum samples. Therefore, the present approach is very promising for application in diagnosing AD within the early stages of the disease.


Assuntos
Doença de Alzheimer/sangue , Técnicas Biossensoriais/métodos , Nanoestruturas/química , Proteínas tau/sangue , Área Sob a Curva , Técnicas Biossensoriais/instrumentação , Ouro/química , Humanos , Limite de Detecção , Medições Luminescentes , Microscopia Eletrônica de Varredura , Nitrilas/química , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Proteínas tau/imunologia
11.
Breast Cancer ; 29(2): 260-273, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34725795

RESUMO

BACKGROUND AND AIM: Vasculogenic mimicry (VM) is one of the most important causes of breast cancer metastasis and resistance against drugs. The cancer stem cells (CSCs) are known as essential factors for VM formation. In this study, the effects of melatonin, Apatinib, and a combination of Apatinib/melatonin on VM formation were investigated by breast CSCs from breast cancer cell line. MATERIALS AND METHODS: The percentage of CSCs was determined in two breast cancer cell lines (MCF-7 and MDA-MB-231) by flow cytometry. The effects of Apatinib, melatonin, and a combination of Apatinib/melatonin were evaluated on proliferation and viability, migration and invasion, apoptosis, and VM formation in MDA-MB-231 cells. Moreover, expression levels of the involved proteins in cancer cell proliferation and viability, CSCs, migration and invasion, and VM formation were evaluated by real-time polymerase chain reaction (RT-PCR) and western blotting methods. RESULTS: Results of the present study showed that melatonin and Apatinib reduced survival rate of CSCs in a dose- and time-dependent manner. Apatinib, melatonin, and a combination of Apatinib/melatonin inhibited proliferation of breast CSCs (P ≤ 0.001). Formation of VM was decreased in the MDA-MB-231 cancer cell line treated with Apatinib and combination of Apatinib/melatonin. Apatinib and combination of Apatinib/melatonin reduced invasion of breast CSCs (P ≤ 0.0001). Expression of vascular endothelial VE-cadherin, ephrinA2 receptor (EPHA2), p-PI3K/phosphoinositide-3 kinase (PI3K) and phospho-AKT (p-AKT)/AKT ratios was decreased under the influence of Apatinib and a combination of Apatinib/melatonin (P ≤ 0.01). CONCLUSION: Apatinib or a combination of Apatinib/melatonin may be used to manage patients with breast cancer. However, further studies are needed to identify anti-cancer mechanisms of melatonin and Apatinib for better management of the patients with breast cancer.


Assuntos
Neoplasias da Mama , Melatonina , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Células MCF-7 , Melatonina/farmacologia , Melatonina/uso terapêutico , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Piridinas
12.
Sci Rep ; 11(1): 23994, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907220

RESUMO

Biopolymer films have drawn growing demand for their application in the point of care domain owing to their biocompatibility, eco-friendly, and eligibility for in vivo analyses. However, their poor conductivity restricts their sensitivity in diagnostics. For high-quality electrochemical biosensor monitoring, two vital factors to be greatly paid attention are the effective merge of amplification modifiers with transducing surface and the superior linking across the recognition interface. Here, we introduce an enzyme-free electrochemical biosensor based on electrosynthesized biocompatible WO3/poly glutamic acid nano-biocomposites to address the hardships specific to the analysis of circulating proteins clinical samples. In addition to its green synthesis route, the poor tendency of both components of the prepared nano-biocomposite to amine groups makes it excellent working in untreated biological samples with high contents of proteins. Several electrochemical and morphological investigations (SEM, EDX, and dot mapping) were fulfilled to gain a reliable and trustful standpoint of the framework. By using this nanobiosensor, the concentration of HER-2 was detectable as low as 1 fg mL-1 with a wide linear response between 1 ng mL-1 and 1 fg mL-1. Meanwhile, the protocol depicted ideal specificity, stability, and reproducibility for the detection of HER-2 protein in untreated serum samples of breast cancer patients.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama/sangue , Técnicas Eletroquímicas , Ácido Glutâmico/química , Nanopartículas Metálicas/química , Nanocompostos/química , Óxidos/química , Receptor ErbB-2/sangue , Tungstênio/química , Feminino , Química Verde , Humanos
14.
Sci Rep ; 11(1): 14921, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290319

RESUMO

In the present article, we developed a highly sensitive label-free electrochemical immunosensor based on NiFe-layered double hydroxides (LDH)/reduced graphene oxide (rGO)/gold nanoparticles modified glassy carbon electrode for the determination of receptor tyrosine kinase-like orphan receptor (ROR)-1. In this electrochemical immunoassay platform, NiFe-LDH/rGO was used due to great electron mobility, high specific surface area and flexible structures, while Au nanoparticles were prepared and coated on the modified electrodes to improve the detection sensitivity and ROR1 antibody immobilizing (ROR1Ab). The modification procedure was approved by using cyclic voltammetry and differential pulse voltammetry based on the response of peak current to the step by step modifications. Under optimum conditions, the experimental results showed that the immunosensor revealed a sensitive response to ROR1 in the range of 0.01-1 pg mL-1, and with a lower limit of quantification of 10 attogram/mL (10 ag mL-1). Furthermore, the designed immunosensor was applied for the analysis of ROR1 in several serum samples of chronic lymphocytic leukemia suffering patients with acceptable results, and it also exhibited good selectivity, reproducibility and stability.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Compostos Férricos , Ouro , Grafite , Hidróxidos , Imunoensaio/métodos , Nanopartículas Metálicas , Nanocompostos , Níquel , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/sangue , Biomarcadores/sangue , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Limite de Detecção , Masculino , Reprodutibilidade dos Testes
15.
Eur J Med Chem ; 222: 113559, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119831

RESUMO

The importance of aldehyde oxidase (AOX) in drug metabolism necessitates the development and application of the in silico rational drug design methods as an integral part of drug discovery projects for the early prediction and modulation of AOX-mediated metabolism. The current study represents an up-to-date and thorough review of in silico studies of AOX-mediated metabolism and modulation methods. In addition, the challenges and the knowledge gap that should be covered have been discussed. The importance of aldehyde oxidase (AOX) in drug metabolism is a hot topic in drug discovery. Different strategies are available for the modulation of the AOX-mediated metabolism of drugs. Application of the rational drug design methods as an integral part of drug discovery projects is necessary for the early prediction of AOX-mediated metabolism. The current study represents a comprehensive review of AOX molecular structure, AOX-mediated reactions, AOX substrates, AOX inhibition, approaches to modify AOX-mediated metabolism, prediction of AOX metabolism/substrates/inhibitors, and the AOX related structure-activity relationship (SAR) studies. Furthermore, an up-to-date and thorough review of in silico studies of AOX metabolism has been carried out. In addition, the challenges and the knowledge gap that should be covered in the scientific literature have been discussed in the current review.


Assuntos
Aldeído Oxidase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Aldeído Oxidase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
16.
Biophys Chem ; 275: 106612, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33984664

RESUMO

Amyloid-ß 1-42 (Aß1-42) aggregation is considered as an important process in the pathology of Alzheimer's disease (AD). Astaxanthin (ATX), a xanthophyll carotenoid, has a broad range of biological activities such as neuroprotective one. The present study aimed to elucidate the interaction of ATX with Aß1-42, as well as its effect on Aß1-42 aggregates under different conditions. Based on the surface plasmon resonance (SPR) results, ATX possessed a high affinity towards Aß1-42 and the binding process was spontaneous, endothermic, and entropy-driven. Additionally, the binding affinity of ATX to Aß1-42 was glucose and insulin concentration-dependent. Hydrophobic interactions may play an important role in the interaction between ATX and Aß1-42. The results of SPR, thioflavin T (ThT), and transmission electron microscopy (TEM) analyses represented the dependency of the anti-amyloid activity of ATX on glucose, insulin, and ATX concentrations. Further, molecular docking results indicated the presence of some same binding sites on Aß1-42 for ATX and glucose, as well as ATX and insulin, which suggests the possible competition between the molecules for Aß1-42 binding. Furthermore, the MTT results confirmed that ATX effect on the viability of Aß1-42-treated PC12 cells was dependent on glucose, insulin, and ATX concentrations. In general, the results provided further insights into the interaction between Aß1-42 and ATX, as well as the effect of ATX on Aß1-42 aggregates under various conditions.


Assuntos
Peptídeos beta-Amiloides/química , Fragmentos de Peptídeos/química , Peptídeos beta-Amiloides/metabolismo , Animais , Simulação de Acoplamento Molecular , Células PC12 , Fragmentos de Peptídeos/metabolismo , Ratos , Ressonância de Plasmônio de Superfície
17.
Turk J Chem ; 45(1): 42-49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679151

RESUMO

Dipyrromethanes are useful mediator structures which can be used as a part of other molecules such as bis-porphyrins and their derivations. Various methods have been developed for their synthesis. This study presents the synthesis of a new bis-dipyrromethane, 7,12-bis(4-(di(1H-pyrrol-2-yl)methyl)phenyl)benzo[k]fluoranthene, using the Lewis acid catalyzed reaction between a new dialdehyde and pyrrole at room temperature. The UV spectroscopic and fluorometric properties of the final product and precursors were determined. The newly synthesized product with desirable UV spectroscopic and fluorometric properties has the potential to be applied as a part of bis-porphyrins or it can be used for other purposes in future studies.

18.
BMC Complement Med Ther ; 21(1): 83, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33663486

RESUMO

BACKGROUND: Vasculogenic mimicry (VM) is characterized by the formation of tubular structure inside the tumor stroma. It has been shown that a small fraction of cancer cells, namely cancer stem cells (CSCs), could stimulate the development of vascular units in the tumor niche, leading to enhanced metastasis to the remote sites. This study aimed to study the inhibitory effect of phytocompound, Thymoquinone (TQ), on human breast MDA-MB-231 cell line via monitoring Wnt/PI3K signaling pathway. METHODS: MDA-MB-231 CSCs were incubated with different concentrations of TQ for 48 h. The viability of CSCs was determined using the MTT assay. The combination of TQ and PI3K and Wnt3a inhibitors was examined in CSCs. By using the Matrigel assay, we measured the tubulogenesis capacity. The percent of CD24- CSCs and Rhodamine 123 efflux capacity was studied using flow cytometry analysis. Protein levels of Akt, p-Akt, Wnt3a, vascular endothelial-cadherin (VE-cadherin), and matrix metalloproteinases-2 and -9 (MMP-2 and -9) were detected by western blotting. RESULTS: TQ decreased the viability of CSCs in a dose-dependent manner. The combination of TQ with PI3K and Wnt3a inhibitors reduced significantly the survival rate compared to the control group (p < 0.05). TQ could blunt the stimulatory effect of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), fibroblast growth factor (FGF) on CSCs (p < 0.05). The vasculogenic capacity of CSCs was reduced after being-exposed to TQ (p < 0.05). Western blotting revealed the decrease of CSCs metastasis by suppressing MMP-2 and -9. The protein level of VE-cadherin was also diminished in TQ-treated CSCs as compared to the control cell (p < 0.05), indicating inhibition of mesenchymal-endothelial transition (MendT). TQ could suppress Wnt3a and PI3K, which coincided with the reduction of the p-Akt/Akt ratio. TQ had the potential to decrease the number of CD24- CSCs and Rhodamine 123 efflux capacity after 48 h. CONCLUSION: TQ could alter the vasculogenic capacity and mesenchymal-epithelial transition of human breast CSCs in vitro. Thus TQ together with anti-angiogenic therapies may be a novel therapeutic agent in the suppression of VM in breast cancer.


Assuntos
Benzoquinonas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase/metabolismo , Proteína Wnt3A/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células-Tronco Neoplásicas
19.
Biosens Bioelectron ; 178: 113023, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33529862

RESUMO

Ultrasensitive monitoring of cancer cells, especially metastatic ones, has a great interest in human medicine. Despite the early diagnosis of diseases, there is an essential need for any prediction in the severity of side effects for therapeutic outcomes like metastasis. Therefore, the inhibition of cancer cells metastasis to other organs is of utmost importance for cancer suffering patients. In this regard, we developed an electrochemiluminescence (ECL)-based cytosensor for the quantification of metastatic breast cancer cells, namely SKBR-3. Silica-based mesoporous materials have a great potential for application in ECL biosensors due to their high loading capacity and mechanical strength. Herein, a silica-based electrode was prepared via in situ electrosyntheses of mesoporous silica as an environmentally friendly approach. In this protocol, luminol (as luminophore) was combined with chitosan (as attachment biomolecule) to produce a stable lumino-composite film on the electrode surface. At the optimum experimental conditions, the lower limit of quantitation (LLOQ) and linear dynamic range (LDR) were obtained as 20 cells/mL and 20 to 2000 cells/mL, individually. The specificity was desirably examined in the presence of other breast cancer cell lines such as MCF-7 and MDA-MB-231, as a model of early-stage and invasive phases of breast cancer cells. The repeatability was successfully examined for five repetitive measurements and the acceptable relative standard deviation (RSD) was calculated as about 1.6% for 500 cells/mL. As a proof of concept, the presented cytosensor has a high ability to use in clinical laboratories for the detection and separation of metastatic cells via the combination with microfluidic systems.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Neoplasias da Mama/diagnóstico , Técnicas Eletroquímicas , Humanos , Limite de Detecção , Medições Luminescentes , Luminol , Células MCF-7
20.
J Biol Eng ; 15(1): 6, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588910

RESUMO

BACKGROUND: The goal of the present study was to create a new biodegradable hybrid PCL-P (HEMA-NIPAAm) thermosensitive hydrogel scaffold by grafting PNIPAAm-based copolymers with biodegradable polyesters to promote the chondrogenic differentiation of human progenitor cells (adipose-derived stem cells-hASCs) in the presence of the platelet-derived growth factor (PDGF-BB). Different mixture ratios including 50 mmol ε-caprolactone and 10 mmol HEMA (S-1), 30 mmol ε-caprolactone and 10 mmol HEMA (S-2), 10 mmol ε-caprolactone and 30 mmol HEMA (S-3) were copolymerized followed by the addition of NIPAAm. RESULTS: A mild to moderate swelling and wettability rates were found in S-2 group copmpared to the S-1 ans S-3 samples. After 7 weeks, S-2 degradation rate reached ~ 43.78%. According to the LCST values, S-2, reaching 37 °C, was selected for different in vitro assays. SEM imaging showed nanoparticulate structure of the scaffold with particle size dimensions of about 62-85 nm. Compressive strength, Young's modulus, and compressive strain (%) of S-2 were 44.8 MPa, 0.7 MPa, and 75.5%. An evaluation of total proteins showed that the scaffold had the potential to gradually release PDGF-BB. When hASCs were cultured on PCL-P (HEMA-NIPAAm) in the presence of PDGF-BB, the cells effectively attached and flattened on the scaffold surface for a period of at least 14 days, the longest time point evaluated, with increased cell viability rates as measured by performing an MTT assay (p < 0.05). Finally, a real-time RT-PCR analysis demonstrated that the combination of PCL-P (HEMA-NIPAAm) and PDGF-BB promoted the chondrogenesis of hASCs over a period of 14 days by up-regulating the expression of aggrecan, type-II collagen, SOX9, and integrin ß1 compared with the non-treated control group (p < 0.05). CONCLUSION: These results demonstrate that the PCL-P(HEMA-NIPAAm) hydrogel scaffold carrying PDGF-BB as a matrix for hASC cell seeding is a valuable system that may be used in the future as a three-dimensional construct for implantation in cartilage injuries.

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