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1.
Anal Biochem ; 661: 114981, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36400147

RESUMO

Biomarkers-based QCM-biosensors are suitable tools for the label-free detection of infectious diseases. In the current study, a QCM-biosensor was developed for the detection of HBsAg. Briefly, anti-HBsAg antibodies were covalently bound to the primary amines after PEI and thiolated-PEI surface modifications of gold-electrode. After RSM optimization, the statistical analysis revealed no significant difference between the immobilization yields of modified layers. Therefore, the PEI-modified QCM-biosensor was selected for further analysis. The PEI-surface was evaluated by FESEM, AFM, ATR-FTIR, and CA measurement. The surface hydrophilicity and its roughness were increased after PEI-coating. Also, FTIR confirmed the PEI-layering on the gold-surface. RSM optimization increased the antibody immobilization yield up to 80%. The QCM-biosensor showed noteworthy results with a wide dynamic range of 1-1 × 103 ng/mL, LOD of 3.14 ng/mL, LOQ of 9.52 ng/mL, and detection capability in human-sera, which were comparable with the ELISA. The mean accuracy of the QCM-biosensor was obtained at 91% when measured by the spike recovery test using human-sera. The biosensor was completely regenerated using 50 mM NaOH and 1% SDS. The benefits provided by the developed biosensor such as broad dynamic range, sensitivity, selectivity, stability, regenerate ability, and low cost suggest its potential application for the non-invasive and timely monitoring of HBV-biomarker.


Assuntos
Ouro , Hepatite B , Humanos , Polietilenoimina , Hepatite B/diagnóstico
2.
Biotechnol Appl Biochem ; 69(6): 2496-2506, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34894353

RESUMO

Targeted drug therapy against cancer has been introduced as a smart strategy to combat the unwanted side effects due to systemic administration of chemotherapeutics. A human serum albumin (HSA)-based nanocarrier was fabricated with the aim to target reductive media and acidic pH of the tumor tissues. α-Lipoic acid (LA) was applied to increase the number of disulfide bonds in the nanocarrier to target higher glutathione concentrations present in tumor tissues and polyethylene glycol was used to target the acidic pH of tumors. UV illumination, ethanol desolvation, oxygen bubbling, and a mixture of redox buffers were employed to prepare doxorubicin-loaded HSA-LA nanoparticles. The nanocarrier was supposed to release the loaded doxorubicin in reductive and acidic pH media. Fourier-transform infrared spectroscopy and energy dispersive X-ray analysis indicated successful attachment of LA to HSA. The prepared nanoplatform presented improved doxorubicin loading efficiency and content and successfully released the loaded doxorubicin in the expected conditions. Protein corona study indicated that positively charged plasma proteins with molecular weights of nearly 80 kDa are absorbed to the surface of the nanoparticles. Furthermore, it showed desirable UV and storage stability, which implied its robustness and improved shelf life if applied in nanomedicine.


Assuntos
Nanopartículas , Neoplasias , Humanos , Albumina Sérica Humana , Doxorrubicina , Nanopartículas/química , Polietilenoglicóis/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos
3.
MAGMA ; 35(1): 3-15, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34878619

RESUMO

OBJECTIVES: We demonstrated a novel metabolic method based on sequential administration of 5-aminolevulinic acid (ALA) and iron supplement, and ferric ammonium citrate (FAC), for glioblastoma multiforme (GBM) detection using R2' and quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: Intra-cellular iron accumulation in glioblastoma cells treated with ALA and/or FAC was measured. Cell phantoms containing glioblastoma cells and Wistar rats bearing C6 glioblastoma were imaged using a 3 T MRI scanner after sequential administration of ALA and FAC. The relaxivity and QSM analysis were performed on the images. RESULTS: The intra-cellular iron deposition was significantly higher in the glioma cells with sequential treatment of ALA and FAC for 6 h compared to those treated with the controls. The relaxivity and magnetic susceptibility values of the glioblastoma cells and rat brain tumors treated with ALA + FAC (115 ± 5 s-1 for R2', and 0.1 ± 0.02 ppm for magnetic susceptibility) were significantly higher than those treated with the controls (55 ± 18 (FAC), 45 ± 15 (ALA) s-1 for R2', p < 0.05, and 0.03 ± 0.03 (FAC), 0.02 ± 0.02 (ALA) ppm for magnetic susceptibility, p < 0.05). DISCUSSION: Sequential administration of ALA and iron supplements increases the iron deposition in glioblastoma cells, enabling clinical 3 T MRI to detect GBM using R2' or QSM.


Assuntos
Glioblastoma , Ácido Aminolevulínico , Animais , Glioblastoma/diagnóstico por imagem , Ferro , Imageamento por Ressonância Magnética/métodos , Ratos , Ratos Wistar
4.
Bioorg Med Chem ; 30: 115944, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33352388

RESUMO

In an attempt to find new potent cytotoxic compounds, several mono- and bis-pyrazolophthalazines 4a-m and 6a-h were synthesized through an efficient, one-pot, three- and pseudo five-component synthetic approach. All derivatives were evaluated for their in vitro cytotoxic activities against four human cancer cell lines of A549, HepG2, MCF-7, and HT29. Compound 4e showed low toxicity against normal cell lines (MRC-5 and MCF 10A, IC50 > 200 µM) and excellent cytotoxic activity against A549 cell line with IC50 value of 1.25 ± 0.19 µM, which was 1.8 times more potent than doxorubicin (IC50 = 2.31 ± 0.13 µM). In addition, compound 6c exhibited remarkable cytotoxic activity against A549 and MCF-7 cell lines (IC50 = 1.35 ± 0.12 and 0.49 ± 0.01 µM, respectively), more than two-fold higher than that of doxorubicin. The binding properties of the best active mono- and bis-pyrazolophthalazine (4e and 6c) with HSA and DNA were fully evaluated by various techniques including UV-Vis absorption, circular dichroism (CD), Zeta potential and dynamic light scattering analyses indicating interaction of the compounds with the secondary structure of HSA and significant change of DNA conformation, presumably via a groove binding mechanism. Additionally, molecular docking and site-selective binding studies confirmed the fundamental interaction of compounds 4e and 6c with base pairs of DNA. Compounds 4e and 6c showed promising features to be considered as potential lead structures for further studies in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , DNA/química , Desenho de Fármacos , Simulação de Acoplamento Molecular , Ftalazinas/farmacologia , Albumina Sérica Humana/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Bovinos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Ftalazinas/síntese química , Ftalazinas/química , Relação Estrutura-Atividade
5.
Bioorg Chem ; 110: 104750, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33691251

RESUMO

A new serise of 7-hydroxy-chromone derivatives bearing pyridine moiety were synthesized, and evaluated as multifunctional agents against Alzheimer's disease (AD). Most of the compounds were good AChE inhibitors (IC50 = 9.8-0.71 µM) and showed remarkable BuChE inhibition activity (IC50 = 1.9-0.006 µM) compared with donepezil as the standard drug (IC50 = 0.023 and 3.4 µM). Compounds 14 and 10 showed the best inhibitory activity toward AChE (IC50 = 0.71 µM) and BuChE (IC50 = 0.006 µM), respectively. The ligand-protein docking simulations and kinetic studies revealed that compound 14 and 10 could bind effectively to the peripheral anionic binding site (PAS) of the AChE and BuChE through mixed-type inhibition. In addition, the most potent compounds showed acceptable neuroprotective activity on H2O2- and Aß-induced .neurotoxicity in PC12 cells, more than standard drugs. The compounds could block effectively self- and AChE-induced Aß aggregation. All the results suggest that compounds 14 and 10 could be considered as promising multi-target-directed ligands against AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cromonas/farmacologia , Desenho de Fármacos , Compostos de Piridínio/farmacologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Cromonas/síntese química , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Células PC12 , Farmacocinética , Conformação Proteica , Compostos de Piridínio/química , Ratos
6.
Bioorg Chem ; 91: 103164, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31398601

RESUMO

Multi-Target approach is particularly promising way to drug discovery against Alzheimer's disease. In the present study, we synthesized a series of compounds comprising the carbazole backbone linked to the benzyl piperazine, benzyl piperidine, pyridine, quinoline, or isoquinoline moiety through an aliphatic linker and evaluated as cholinesterase inhibitors. The synthesized compounds showed IC50 values of 0.11-36.5 µM and 0.02-98.6 µM against acetyl- and butyrylcholinesterase (AChE and BuChE), respectively. The ligand-protein docking simulations and kinetic studies revealed that compound 3s could bind effectively to the peripheral anionic binding site (PAS) and anionic site of the enzyme with mixed-type inhibition. Compound 3s was the most potent compound against AChE and BuChE and showed acceptable inhibition potency for self- and AChE-induced Aß1-42 aggregation. Moreover, compound 3s could significantly protect PC12 cells against H2O2-induced toxicity. The results suggested that the compounds 3s could be considered as a promising multi-functional agent for further drug discovery development against Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/química , Antioxidantes/farmacologia , Carbazóis/química , Inibidores da Colinesterase/farmacologia , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/química , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Antioxidantes/química , Inibidores da Colinesterase/química , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/química , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos
7.
Bioorg Chem ; 83: 559-568, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30471578

RESUMO

A novel series of benzylpyridinium-based benzoheterocycles (benzimidazole, benzoxazole or benzothiazole) were designed as potent acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors. The title compounds 4a-q were conveniently synthesized via condensation reaction of 1,2-phenylenediamine, 2-aminophenol or 2-aminothiophenol with pyridin-4-carbalehyde, followed by N-benzylation using various benzyl halides. The results of in vitro biological assays revealed that most of them, especially 4c and 4g, had potent anticholinesterase activity comparable or more potent than reference drug, donepezil. The kinetic study demonstrated that the representative compound 4c inhibits AChE in competitive manner. According to the ligand-enzyme docking simulation, compound 4c occupied the active site at the vicinity of catalytic triad. The compounds 4c and 4g were found to be inhibitors of Aß self-aggregation as well as AChE-induced Aß aggregation. Meanwhile, these compounds could significantly protect PC12 cells against H2O2-induced injury and showed no toxicity against HepG2 cells. As multi-targeted structures, compounds 4c and 4g could be considered as promising candidate for further lead developments to treat Alzheimer's disease.


Assuntos
Compostos Heterocíclicos com 2 Anéis/farmacologia , Fármacos Neuroprotetores/farmacologia , Compostos de Piridínio/farmacologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Butirilcolinesterase/metabolismo , Linhagem Celular Tumoral , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/toxicidade , Desenho de Fármacos , Electrophorus , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/metabolismo , Compostos Heterocíclicos com 2 Anéis/toxicidade , Cavalos , Humanos , Peróxido de Hidrogênio/farmacologia , Cinética , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Compostos de Piridínio/síntese química , Compostos de Piridínio/metabolismo , Compostos de Piridínio/toxicidade , Ratos , Torpedo
8.
J Nanosci Nanotechnol ; 19(2): 655-663, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360137

RESUMO

In this work, a new magnetic nanocomposite was prepared for the specific isolation of CD45 positive cells. Acrolein (AC) and acrylated ß-cyclodextrin (ACD) were used as monomers in order to polymerize on the surface of Fe3O4 magnetic nanoparticles (MNPs) via surface initiated radical polymerization. Polyacrolein-ß-CD (PACD) functionalized Fe3O4 MNPs (Fe3O4@PACD) was achieved and subsequently, fluorescein conjugated IgG anti-human CD45 was immobilized onto Fe3O4@PACD. Antibody conjugation onto the latter nanocomposite was accomplished according to IgG encapsulation in cyclodextrin cavity and Schiff base formation between aldehyde groups of MNPs and primary amines of antibody. The characterization analysis of the bare Fe3O4, Fe3O4@PACD nanocomposite, and Fe3O4@PACD-Ab were investigated using XRD, VSM, FT-IR, H-NMR, TGA, SEM, TEM, and flow cytometry techniques. The results showed that the antibody has been successfully immobilized onto Fe3O4@PACD. Moreover, the fabricated nanocomposite was used for selective capturing of CD45+ cells among other peripheral blood mononuclear cells (PBMCs). The results of TEM and fluorescence microscopy confirmed the ability of the conjugated system for efficient cell capturing.


Assuntos
Nanopartículas de Magnetita , beta-Ciclodextrinas , Acroleína , Leucócitos Mononucleares , Espectroscopia de Infravermelho com Transformada de Fourier
9.
MAGMA ; 32(4): 487-500, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30730021

RESUMO

OBJECTIVES: In this study, a novel targeted MRI contrast agent was developed by coating gadolinium oxide nanoparticles (Gd2O3 NPs) with ß-cyclodextrin (CD)-based polyester and targeted by folic acid (FA). MATERIALS AND METHODS: The developed Gd2O3@PCD-FA MRI contrast agent was characterized and evaluated in relaxivity, in vitro cell targeting, cell toxicity, blood compatibility and in vivo tumor MR contrast enhancement. RESULTS: In vitro cytotoxicity and hemolysis assays revealed that Gd2O3@PCD-FA NPs have no significant cytotoxicity after 24 and 48 h against normal human breast cell line (MCF-10A) at concentration of up to 50 µg Gd+3/mL and have high blood compatibility at concentration of up to 500 µg Gd+3/mL. In vitro MR imaging experiments showed that Gd2O3@PCD-FA NPs enable targeted contrast T1- and T2-weighted MR imaging of M109 as overexpressing folate receptor cells. Besides, the in vivo analysis indicated that the maximum contrast-to-noise ratio (CNR) of tumor in mice increased after injection of Gd2O3@PCD-FA up to 5.89 ± 1.3 within 1 h under T1-weighted imaging mode and reduced to 1.45 ± 0.44 after 12 h. While CNR increased up to maximum value of 1.98 ± 0.28 after injection of Gd2O3@PCD within 6 h and reduced to 1.12 ± 0.13 within 12 h. CONCLUSION: The results indicate the potential of Gd2O3@PCD-FA to serve as a novel targeted nano-contrast agent in MRI.


Assuntos
Meios de Contraste/farmacologia , Ciclodextrinas/química , Ácido Fólico/química , Gadolínio/química , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Ácido Pentético/química , Animais , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis , Relação Dose-Resposta a Droga , Hemólise , Humanos , Imageamento por Ressonância Magnética , Camundongos , Transplante de Neoplasias , Termogravimetria
10.
Chem Biodivers ; 16(5): e1800436, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30957958

RESUMO

Two series of novel coumarin derivatives, substituted at 3 and 7 positions with aminoalkoxy groups, are synthesized, characterized, and screened. The effect of amine substituents and the length of cross-linker are investigated in acetyl- and butyrylcholinesterase (AChE and BuChE) inhibition. Target compounds show moderate to potent inhibitory activities against AChE and BuChE. 3-(3,4-Dichlorophenyl)-7-[4-(diethylamino)butoxy]-2H-chromen-2-one (4y) is identified as the most potent compound against AChE (IC50 =0.27 µm). Kinetic and molecular modeling studies affirmed that compound 4y works in a mixed-type way and interacts simultaneously with the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. In addition, compound 4y blocks ß-amyloid (Aß) self-aggregation with a ratio of 44.11 % at 100 µm and significantly protects PC12 cells from H2 O2 -damage in a dose-dependent manner.


Assuntos
Cumarínicos/química , Ligantes , Fármacos Neuroprotetores/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Cumarínicos/farmacologia , Cumarínicos/uso terapêutico , Humanos , Peróxido de Hidrogênio/toxicidade , Concentração Inibidora 50 , Cinética , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Ratos , Relação Estrutura-Atividade
11.
Bioorg Chem ; 79: 223-234, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29775948

RESUMO

New series of triazole-containing 3-phenylcoumarin-lipoic acid conjugates were designed as multi-functional agents for treatment of Alzheimer's disease. The target compounds 4a-o were synthesized via the azide-alkyne cycloaddition reaction and their biological activities were primarily evaluated in terms of neuroprotection against H2O2-induced cell death in PC12 cells and AChE/BuChE inhibition. The promising compounds 4j and 4i containing four carbons spacer were selected for further biological evaluations. Based on the obtained results, the benzocoumarin derivative 4j with IC50 value of 7.3 µM was the most potent AChE inhibitor and displayed good inhibition toward intracellular reactive oxygen species (ROS). This compound with antioxidant and metal chelating ability showed also protective effect on cell injury induced by Aß1-42 in SH-SY5Y cells. Although the 8-methoxycoumarin analog 4i was slightly less active than 4j against AChE, but displayed higher protection ability against H2O2-induced cell death in PC12 and could significantly block Aß-aggregation. The results suggested that the prototype compounds 4i and 4j might be promising multi-functional agents for the further development of the disease-modifying treatments of Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cumarínicos/farmacologia , Fármacos Neuroprotetores/farmacologia , Ácido Tióctico/farmacologia , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Linhagem Celular Tumoral , Cumarínicos/síntese química , Cumarínicos/química , Cumarínicos/uso terapêutico , Relação Dose-Resposta a Droga , Humanos , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Ácido Tióctico/síntese química , Ácido Tióctico/química , Ácido Tióctico/uso terapêutico
12.
Water Sci Technol ; 77(5-6): 1558-1569, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29595158

RESUMO

The aim of this study was to investigate membrane synthesis by interfacial polymerization methods, the application of synthesized nano-composite membrane for natural organic matters (NOMs) removal from water, evaluation of fouling mechanism and antifouling properties. Polysulfone (PSf) was selected as a porous ultrafiltration membrane support and interfacial polymerization was done using tannic acid (TA) and Trimesoyl chloride (TMC) with central composite design (CCD). The effects of TA and TMC monomer concentrations, reaction time and post treatment temperature was evaluated. The synthesized membrane was characterized by field emission scanning electron microscope (FESEM), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and water contact angle. Based on the results, the optimum conditions for synthesizing nano-composite were: TA concentration of 0.27 g/L, TMC concentration of 0.22 g/L, reaction time of 68.29 min and temperature of 25.23 °C. The predicted optimum operational conditions were a NOM concentration of 6.429 mg/L; time of 10.931 min and applied pressure of 1.039 bar. The potential applications of the synthesized nano-composite membranes with interfacial polymerization can enhance water treatment.


Assuntos
Membranas Artificiais , Nanocompostos , Polímeros/química , Sulfonas/química , Microscopia de Força Atômica , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Ultrafiltração , Água , Poluentes Químicos da Água , Purificação da Água
13.
J Fluoresc ; 27(2): 529-536, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27858297

RESUMO

This study was designed to develop a highly selective and sensitive method towards fluorimetric sensing of cysteine (Cys) in water and human serum by using copper nanocluster. The Cys-CuNCs were characterized by scanning electron microscopy (SEM), FTIR, fluorescence and UV-Vis analysis. Spectroscopic evidences showed different intensities that were attributed to the different size of Cys-CuNCs. Enhancement in fluorescence intensity of copper nanoclusters with an increase in concentration of cysteine may enable them to be good candidates in detection systems. Selective recognition of cysteine in aqueous and serum samples was achieved during the formation of various copper nanoclusters (Cys-CuNCs) with different size. Under the optimized conditions, two linear range of the nanobiosensor for cysteine were between the 5 µM to 50 µM with detection limit of 2.4 µM and between 60 µM to 500 µM with detection limit of 55 µM. Fluorescence intensity increased with addition of cysteine concentration from 5 to 50 µM. The proposed low-cost nanobiosensor exhibited high reproducibility and good selectivity. It has been used also for the determination of cysteine in human serum samples with recoveries of 97-103 % and RSDs of 1.8-3.6.

14.
Phys Chem Chem Phys ; 19(15): 10099-10115, 2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28367545

RESUMO

Ligand binding studies on human serum albumin (HSA) are crucial in determining the pharmacological properties of drug candidates. Here, two representatives of coumarin-chalcone hybrids were selected and their binding mechanism was identified via thermodynamics techniques, curve resolution analysis and computational methods at molecular levels. The binding parameters were derived using spectroscopic approaches and the results point to only one pocket located near the Trp214 residue in subdomain IIA of HSA. The protein tertiary structure was altered during ligand binding and formed an intermediate structure to create stronger ligand binding interactions. The best binding mode of the ligand was initially estimated by docking on an ensemble of HSA crystallographic structures and by molecular dynamics (MD) simulations. Per residue interaction energies were calculated over the MD trajectories as well. Reasonable agreement was found between experimental and theoretical results about the nature of binding, which was dominated by hydrogen bonding and van der Waals contributions.


Assuntos
Cumarínicos/metabolismo , Albumina Sérica Humana/metabolismo , Sítios de Ligação , Calorimetria , Chalcona/química , Dicroísmo Circular , Cumarínicos/química , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Albumina Sérica Humana/química , Espectrometria de Fluorescência , Eletricidade Estática , Termodinâmica
15.
Luminescence ; 32(6): 1045-1050, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28220689

RESUMO

A remarkable method for the highly sensitive detection of phenylalanine and tryptophan based on a chemiluminescence (CL) assay was reported. It was found that fluorescent copper nanoclusters capped with cysteine (Cys-CuNCs) strongly enhance the weak CL signal resulting from the reaction between luminol and H2 O2 . Of the amino acids tested, phenylalanine and tryptophan could enhance the above CL system sensitively. Under optimum conditions, this method was satisfactorily described by a linear calibration curve over a range of 1.0 × 10-6 to 2.7 × 10-5  M for phenylalanine and 1.0 × 10-7 to 3.0 × 10-5  M for tryptophan, respectively. The effect of various parameters such as Cys-CuNC concentration, H2 O2 concentration and pH on the intensity of the CL system were also studied. The main experimental advantage of the proposed method was its selectivity for two amino acids compared with others. To evaluate the applicability of the method to the analysis of a real biological sample it was used to determine tryptophan and phenylalanine in human serum and remarkable results were obtained.


Assuntos
Cobre/química , Medições Luminescentes/métodos , Luminol/química , Fenilalanina/sangue , Triptofano/sangue , Humanos , Luminescência , Medições Luminescentes/instrumentação , Sensibilidade e Especificidade
16.
J Enzyme Inhib Med Chem ; 30(3): 389-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26095345

RESUMO

A series of 5-benzylidenerhodanine-3-acetamides bearing morpholino-, 4-arylpiperazinyl-, or 4-benzylpiperidinyl- moieties were synthesized and their inhibitory activities against acetylcholinesterase (AChE) were evaluated. Alteration of amide part and substitution on the benzylidene moiety resulted in change of anti-AChE activity. The most active compound was the 1-benzylpiperidinyl derivative containing 4-(dimethylamino)benzylidene scaffold. Notably, the intermediate compounds, namely 5-arylidene-rhodanine-3-acetic acids (3), showed mild inhibitory activity against 15-lipoxygenase (15-LOX), while the final compound 4 showed no activity against 15-LOX.


Assuntos
Acetatos/farmacologia , Acetilcolinesterase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Rodanina/análogos & derivados , Acetatos/síntese química , Acetatos/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Rodanina/síntese química , Rodanina/química , Rodanina/farmacologia , Relação Estrutura-Atividade
17.
Arch Pharm (Weinheim) ; 348(5): 366-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25820388

RESUMO

A series of triazole-containing carbazole derivatives were designed as new anti-acetylcholinesterase (AChE) agents. The target compounds 6a-q were simply prepared via a one-pot three-component click reaction of N-propargyl-9H-carbazole, sodium azide, and an appropriate benzyl halide. The in vitro anti-cholinesterase assay showed that the unsubstituted benzyl derivative 6p along with the 2-F, 2-Me, 3-Me, 3-MeO, and 3-F analogs (6a, 6c, and 6g-i) had significant anti-AChE activity (IC50s ≤ 3.8 µM). Among them, the 2-methylbenzyl derivative 6c with an IC50 value of 1.9 µM was the most active compound. The SAR studies revealed that small halogen atoms such as the fluorine atom or electron-donating groups such as methyl or methoxy at the ortho or meta positions of the benzyl pendent group could be tolerated or improved the anti-AChE activity.


Assuntos
Carbazóis/farmacologia , Inibidores da Colinesterase/farmacologia , Triazóis/farmacologia , Acetilcolinesterase/metabolismo , Sítios de Ligação , Carbazóis/síntese química , Carbazóis/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/metabolismo , Desenho de Fármacos , Cinética , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/metabolismo
18.
Daru ; 22(1): 9, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24398032

RESUMO

BACKGROUND: Coumarins are an important class of widely distributed heterocyclic natural products exhibiting a broad pharmacological profile. In this work, a new series of coumarins bearing substituted 3,4-dihydro-2H-benzothiazines were described as potential analgesic agents. The clinical use of NSAIDs as traditional analgesics is associated with side effects such as gastrointestinal lesions and nephrotoxicity. Therefore, the discovery of new safer drugs represents a challenging goal for such a research area. RESULTS: The target compounds 3-(3-methyl-3,4-dihydro-2H-benzo[b][1,4]thiazin-3-yl)-2H-chromen-2-ones 2a-u were synthesized and characterized by spectral data. The antinociceptive properties of target compounds were determined by formalin-induced test and acetic acid-induced writhing test in mice. Among the tested compounds, compound 2u bearing 2-(4-(methylsulfonyl)benzoyl)- moiety on benzothiazine ring and 4-(methylsulfonyl)phenacyloxy- group on the 7 position of coumarin nucleus showed better profile of antinocecieption in both models. It was more effective than mefenamic acid during the late phase of formalin-induced test as well as in the acetic acid-induced writhing test. CONCLUSION: Considering the significant antinoceciptive action of phenacyloxycoumarin derivatives, compound 2u prototype might be further used as model to obtain new more potent analgesic drugs.

19.
Magn Reson Imaging ; 107: 120-129, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38215955

RESUMO

The use of conventional gadolinium(Gd)-based contrast agents in magnetic resonance imaging (MRI) poses a significant risk of Nephrogenic Systemic Fibrosis (NSF) syndrome in patients with impaired renal function (grades 4 and 5). To address this issue, a new study has introduced a novel metabolic Gadolinium oxide nanoparticle (Gd2O3 NPs) coated with ß-cyclodextrin (ßCD). The study aims to investigate NSF syndrome by quantifying tissue Gd deposition biodistribution in renal impairment rats using MR molecular imaging. This is the first study of its kind to use this approach. A group of 20 rats were divided into four groups, each containing five rats that underwent 5/6 nephrectomy. The rats received 12 intravenous injections of a novel homemade synthesized gadolinium oxide polycyclodextrin (Gd2O3@PCD) at a dose of 0.1 mmol/kg, conventional contrast agents (CAs) drugs of Omniscan (Gd-DTPA-BMA) and Dotarem (Gd-DOTA), at a dose of 2.5 mmol/kg, and 250 µl saline for two injections per week during six weeks. T1-weighted MR imaging was performed before the injections and once a week for six weeks to quantify Gd deposition in four different organs (skin, liver, heart, and lung) in rats using inductively coupled plasma mass spectrometry (ICP-MS). The relationship between Signal-to-Noise Ratio (SNR) and biodistribution of Gd deposition due to NSF-induced syndrome was also calculated. The results of the study showed that the Gd concentrations in tissues were significantly higher in the Gd2O3@PCD group compared to the other groups, without any significant histopathological changes (P < 0.05). In the Gd2O3@PCD group, Gd was mainly deposited in the skin, followed by the liver, lung, and heart, without any symptoms of thickening or hardening of the skin. The Gd concentrations in the skin, liver, lung, and heart were significantly lower in the Dotarem group than in the Omniscan group (P < 0.05). In the histopathological examinations, the Omniscan group showed increased cellularity in the dermis. A significant hyperintensity was observed in the Gd2O3@PCD-treated rats compared to the Dotarem and Omniscan groups in the liver, heart, and lung. Compared to conventional Gd-based CAs, the novel metabolically Gd2O3@PCD with increased SNR, biosafety, and a considerably lower probability of developing NSF, has potential applicability for diagnosing patients with renal diseases in clinical MR Molecular Imaging (MRMI).


Assuntos
Meglumina , Nanopartículas , Dermopatia Fibrosante Nefrogênica , Compostos Organometálicos , Insuficiência Renal , beta-Ciclodextrinas , Humanos , Ratos , Animais , Meios de Contraste/efeitos adversos , Dermopatia Fibrosante Nefrogênica/induzido quimicamente , Gadolínio/efeitos adversos , Ratos Wistar , Distribuição Tecidual , Gadolínio DTPA , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/metabolismo , Insuficiência Renal/patologia , beta-Ciclodextrinas/efeitos adversos , Imageamento por Ressonância Magnética , Imagem Molecular
20.
Heliyon ; 10(7): e28355, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571593

RESUMO

Purpose: Gadolinium-enhancing necrosis in glioblastoma multiforme (GBM), as an occasionally occurring false positive in contrast enhancement (CE) imaging, leads to trouble for segmentation of GBM and treatment. Therefore, the investigation of complementary detection way to identify the metabolically active volume of the tumor with high reliability is very worth to be addressed. Here, we reported on a case of GBM with gadolinium-enhancing necrosis in an experimental CE imaging study in mice and evaluated the discrimination of the necrosis and metabolically active parts of the GBM using conventional and state-of-the-art susceptibility-based MRI. Methods: In this study, following 5-aminolevulinic acid (ALA) and iron supplements (FAC, 6 h after ALA, intra-tumoral injection) to animal, T2*-W imaging and quantitative susceptibility mapping (QSM) were performed, and compared with CE imaging. Results: The signal intensity (SI) of the active and necrosis areas of the case in the CE image demonstrated no significant difference while the SI on the T2*-W images and susceptibility value in QSM changed 24 and 150%, respectively. Conclusion: The preclinical case report provides valuable insights into the potential of susceptibility-based MRI using ALA + FAC to apply as a robust discriminator between necrotic and viable tumors.

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