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1.
Int J Mol Sci ; 25(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38891841

RESUMO

Ailanthus altissima, an invasive plant species, exhibits pharmacological properties, but also some allergic effects on humans. This study aimed to evaluate the potential toxicity of A. altissima leaves, using a complex approach towards different organisms. The ecotoxic impact of a crude extract was investigated on seeds germination and brine shrimp lethality. Cytotoxicity was studied in vitro using non-target (haemolysis, liposomal model, fibroblast), and target (cancer cells) assays. Leaf extract at 1000 µg/mL significantly inhibited wheat and tomato germination, while no significant effects were found on parsley germination. A slight stimulatory effect on wheat and tomato germination was found at 125 µg/mL. In a brine shrimp-test, the extract showed a low toxicity at 24 h post-exposure (LC50 = 951.04 ± 28.26 µg/mL), the toxic effects increasing with the exposure time and extract concentration. Leaf extract caused low hematotoxicity. The extract was biocompatible with human gingival fibroblasts. No anti-proliferative effect was found within the concentration range of 10-500 µg/mL on malignant melanoma (MeWo) and hepatocellular carcinoma (HepG2). In a liposomal model-test, the extract proved to possess low capability to alter the eukaryotic cell-mimicking membranes within the tested concentration range. Given the low to moderate toxicity on tested organisms/cells, the A. altissima autumn leaves may find useful applications.


Assuntos
Ailanthus , Artemia , Extratos Vegetais , Folhas de Planta , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ailanthus/química , Animais , Folhas de Planta/química , Humanos , Artemia/efeitos dos fármacos , Germinação/efeitos dos fármacos , Células Hep G2 , Sementes/química , Fibroblastos/efeitos dos fármacos , Linhagem Celular Tumoral
2.
Molecules ; 29(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398524

RESUMO

6-Iodo-substituted carboxy-quinolines were obtained using a one-pot, three-component method with trifluoroacetic acid as a catalyst under acidic conditions. Iodo-aniline, pyruvic acid and 22 phenyl-substituted aldehydes (we varied the type and number of radicals) or O-heterocycles, resulting in different electronic effects, were the starting components. This approach offers advantages such as rapid response times, cost-effective catalysts, high product yields and efficient purification procedures. A comprehensive investigation was conducted to examine the impact of aldehyde structure on the synthesis pathway. A library of compounds was obtained and characterized by FT-IR, MS, 1H NMR and 13C NMR spectroscopy and single-ray crystal diffractometry. Their antimicrobial activity against S. epidermidis, K. pneumonie and C. parapsilosis was tested in vitro. The effect of iodo-quinoline derivatives on microbial adhesion, the initial stage of microbial biofilm development, was also investigated. This study suggests that carboxy-quinoline derivatives bearing an iodine atom are interesting scaffolds for the development of novel antimicrobial agents.


Assuntos
Anti-Infecciosos , Iodo , Quinolinas , Espectroscopia de Infravermelho com Transformada de Fourier , Anti-Infecciosos/química , Quinolinas/química
3.
Int J Mol Sci ; 23(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35682618

RESUMO

Zoledronic acid (ZA) is used in the treatment of various bone pathologies, but it forms complexes with calcium ions present in body fluids, decreasing ZA bioavailability. Thereby, the study first describes the identification of ZA-calcium complexes that form in calcium-rich environments, in order to establish the bioavailable ZA concentration. Then, a new method for quantification of low ZA amounts in milieus that mimics in vivo conditions by using simulated body fluid and calcium sulfate hemihydrate was described. Almost all analytical methods of ZA quantification described in the literature require compound derivatization. At very low concentrations, derivatization is prone to analyte loss, therefore compromising the analytical results. In our study, we avoided ZA derivatization by using a high-performance liquid chromatography and electrospray ionization mass spectrometry (HPLC-ESI-MS) system, conducting the investigation based on the fragmentation mass extracted ion chromatograms specific to the ZA protonated form. The method was validated by selectivity, precision, accuracy, linearity, signal to noise ratio, and limit of detection and limit of quantification calculation. Experimentally, this method can detect ranges of 0.1-0.5 ng/mL and precisely quantify ZA concentrations as low as 0.1 ng/mL. This method could provide the basis for quantifying low amounts of ZA in the blood during long-term administration.


Assuntos
Cálcio , Espectrometria de Massas por Ionização por Electrospray , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Ácido Zoledrônico
4.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361832

RESUMO

In recent times, researchers have aimed for new strategies to combat cancer by the implementation of nanotechnologies in biomedical applications. This work focuses on developing protein-based nanoparticles loaded with a newly synthesized NIR emitting and absorbing phthalocyanine dye, with photodynamic and photothermal properties. More precisely, we synthesized highly reproducible bovine serum albumin-based nanoparticles (75% particle yield) through a two-step protocol and successfully encapsulated the NIR active photosensitizer agent, achieving a good loading efficiency of 91%. Making use of molecular docking simulations, we confirm that the NIR photosensitizer is well protected within the nanoparticles, docked in site I of the albumin molecule. Encouraging results were obtained for our nanoparticles towards biomedical use, thanks to their negatively charged surface (-13.6 ± 0.5 mV) and hydrodynamic diameter (25.06 ± 0.62 nm), favorable for benefitting from the enhanced permeability and retention effect; moreover, the MTT viability assay upholds the good biocompatibility of our NIR active nanoparticles. Finally, upon irradiation with an NIR 785 nm laser, the dual phototherapeutic effect of our NIR fluorescent nanoparticles was highlighted by their excellent light-to-heat conversion performance (photothermal conversion efficiency 20%) and good photothermal and size stability, supporting their further implementation as fluorescent therapeutic agents in biomedical applications.


Assuntos
Indóis/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Soroalbumina Bovina/química , Proliferação de Células , Feminino , Humanos , Indóis/química , Isoindóis , Luz , Simulação de Acoplamento Molecular , Nanopartículas/química , Neoplasias Ovarianas/patologia , Fármacos Fotossensibilizantes/química , Espectroscopia de Luz Próxima ao Infravermelho , Células Tumorais Cultivadas
5.
Molecules ; 25(19)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987884

RESUMO

We have designed and synthesized a series of novel, supramolecular, long-lived fluorescent probes based on the host-guest inclusion complexes formation between fluorescent indolizinyl-pyridinium salts and ß-cyclodextrin. Fluorescence and electrospray ionisation mass spectrometry experiments, supported by theoretical molecular docking studies, were utilized in the monitoring of the inclusion complexes formation, evidencing the appearance of corresponding 1:1 and 1:2 species. Additionally, the influence of the guest molecule over the aggregation processes of the cyclodextrin inclusion complexes was investigated by transmission electron microscopy. The absence of cytotoxicity, cellular permeability, long-lived intracellular fluorescence, and in time specific accumulation within acidic organelles identified the investigated supramolecular entities as remarkable candidates for intracellular fluorescence probes. Co-staining experiments using specific organelle markers revealed the fact that, after a 24-h incubation period, the inclusion complexes accumulate predominantly in lysosomes rather than in mitochondria. This study opens new possibilities for a broad range of fluorescent dyes with solubility and high toxicity issues, able to form inclusion complexes with ß-cyclodextrin, to be tested as intracellular fluorescence probes.


Assuntos
Ciclodextrinas/química , Corantes Fluorescentes/química , Simulação de Acoplamento Molecular , Espectrometria de Fluorescência
6.
Adv Exp Med Biol ; 1140: 685-701, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347079

RESUMO

An important and well-designed solution to overcome some of the problems associated with new drugs is provided by the molecular encapsulation of the drugs in the cyclodextrins (CDs) cavity, yielding corresponding inclusion complexes (ICs). These types of non-covalent complexes are of current interest to the pharmaceutical industry, as they improve the solubility, stability and bioavailability of the guest molecules. This review highlights several methods for cyclodextrin ICs preparation and characterization, focusing mostly on the mass spectrometry (MS) studies that have been used for the detection of noncovalent interactions of CDs inclusion complexes and binding selectivity of guest molecules with CDs. Furthermore, the MS investigations of several ICs of the CD with antifungal, antioxidants or fluorescent dyes are presented in greater details, pointing out the difficulties overcome in the analysis of this type of compounds.


Assuntos
Química Farmacêutica/métodos , Ciclodextrinas/análise , Espectrometria de Massas , Solubilidade
7.
Chemistry ; 20(22): 6678-83, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24756773

RESUMO

Herein, we consider Müller's spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42[{(Mo(VI))Mo(VI)5O21(H2O)6}12{Mo(V)2O4(CH3COO)}30]⋅10 CH3COONH4⋅300 H2O≡(NH4)42⋅1 a⋅crystal ingredients≡1, {Mo132}, as an effective sugar-decorated nanoplatform for multivalent lectin recognition. The ion-exchange of NH4(+) ions of 1 with cationic-sugars, D-mannose-ammonium chloride (2) or D-glucose-ammonium chloride (3) results in the formation of glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a. The Mannose (NH4)(42-n)2n⋅1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of K(a)(multi)=4.6×10(4) M(-1) and an enhancement factor of ß=K(a)(multi)/K(ass)(mono)=21.9, reminiscent of the formation of "glycoside clusters" on the external surface of glyconanocapsule. The glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a self-assemble in "hybrid multilayers" by successive layer-by-layer deposition of (NH4)(42-n)2n⋅1 a or (NH4)(42-m)3m⋅1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The "biomimetic hybrid multilayers" described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage-delivery devices.


Assuntos
Materiais Biocompatíveis/química , Concanavalina A/química , Molibdênio/química , Nanocápsulas/química , Cloreto de Amônio/química , Glucose/química , Cinética , Manose/química , Ligação Proteica , Técnicas de Microbalança de Cristal de Quartzo , Compostos de Tungstênio/química
8.
Antioxidants (Basel) ; 13(7)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39061893

RESUMO

Ailanthus altissima, a highly invasive species, contains valuable compounds in different plant parts, indicating great practical potential. This paper proposes the use of non-polar (n-hexane) and polar (ethanol) solvents for the extraction of antioxidant compounds from A. altissima (family Simaroubaceae) leaves in a sequential two-step process. Fresh and dried leaves were examined for their microstructure by scanning electron microscopy, and for color changes in the CIELAB color space co-ordinates. An investigation of the harvesting season, processing (freezing and drying), and solvent indicates ethanol can be used for the highly efficient extraction of phenolics, flavonoids, tannins, and carotenoids. Statistically significant differences were found between the autumn and summer samples for phenolic content, and between dried and frozen samples for tannin content. The HPLC phenolic profile indicates more phenolics (nine polyphenols) in dried leaves harvested in both seasons compared to those in frozen ones (five to six polyphenols). Frozen leaves showed a higher antioxidant activity in a ferric-reducing antioxidant power assay than that of the dried samples, which exhibited a higher antioxidant activity using the 1, 1-diphenyl-2-picryl-hydrazyl assay, but it was not statistically significant. The phenolic, flavonoid, and carotenoid contents significantly influenced the antioxidant activities. Among the ethanolic extracts, those from dried leaves showed better antibacterial activity, in particular, on Staphylococcus aureus and Enterococcus faecalis. The high bioactive content and activity of A. altissima leaves make them suitable natural raw materials for various applications.

9.
J Med Chem ; 67(4): 3018-3038, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38301036

RESUMO

New dihydro-pyrrol-2-one compounds, featuring dual sulfonamide groups, were synthesized through a one-pot, three-component approach utilizing trifluoroacetic acid as a catalyst. Computational analysis using density functional theory (DFT) and condensed Fukui function explored the structure-reactivity relationship. Evaluation against human carbonic anhydrase isoforms (hCA I, II, IX, XII) revealed potent inhibition. The widely expressed cytosolic hCA I was inhibited across a range of concentrations (KI 3.9-870.9 nM). hCA II, also cytosolic, exhibited good inhibition as well. Notably, all compounds effectively inhibited tumor-associated hCA IX (KI 1.9-211.2 nM) and hCA XII (low nanomolar). Biological assessments on MCF7 cancer cells highlighted the compounds' ability, in conjunction with doxorubicin, to significantly impact tumor cell viability. These findings underscore the potential therapeutic relevance of the synthesized compounds in cancer treatment.


Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Inibidores da Anidrase Carbônica/farmacologia , Anidrase Carbônica IX , Relação Estrutura-Atividade , Anidrases Carbônicas/metabolismo , Isoformas de Proteínas , Estrutura Molecular , Antígenos de Neoplasias
10.
Beilstein J Org Chem ; 9: 1285-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23843924

RESUMO

Full characterization of fullerenol C60(OH)24 by HPLC ESI-MS in negative and positive ionization modes was achieved. Fragmentor voltage and capillary voltage were optimized in order to obtain a good signal stability and the best peak intensity distribution for the fullerenol C60(OH)24 in both negative and positive modes. While the predominant base peak observed for C60(OH)24 in the negative ionization mode was [M - H](-) at m/z 1127, those observed in the positive mode were multiply charged [M - H2O + 4H](4+) at m/z 279 and [M - 12H2O + 2NH3 + 6H](6+) at m/z 158.

11.
Polymers (Basel) ; 15(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37836077

RESUMO

The present work is focused on polyester resins obtained from the diglycidyl ether of bisphenol A and anthracene modified 5-maleimidoisophthalic acid. Because the maleimide-anthracene Diels-Alder (DA) adduct is stable at high temperatures, it is considered a good option for high performance polymers. However, the information related to the retroDA reaction for this type of adduct is sometimes incoherent. A detailed thermal study (conventional TGA, HiRes TGA, MTGA, DSC, MDSC) was performed in order to establish whether the rDA reaction can be revealed for this type of anthracene modified polyester resins. The TGA method confirmed the cleavage of the anthracene-maleimide DA adduct, while the DSC demonstrated the presence of anthracene in the system. At high temperatures, unprotected maleimide homopolymerizes and/or reacts with allyl groups according to the -ene reaction. Therefore, the thermal DA reaction is not displayed anymore upon the subsequent cooling, and the glass transition region is registered at a higher temperature range during the second heating. The use of sample-controlled thermal analysis (HiRes TGA) and MTGA improved the TGA result; however, it was not possible to separate the very complex degradation processes that are interconnected.

12.
Biomater Adv ; 144: 213201, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36436432

RESUMO

Cargocomplexes play a vital role in non-viral delivery methods due to their capacity to target certain cells (or cells through the cell-division cycle) and inject their (macro)molecular "cargo" into them. The development of gene carriers that can efficiently transport and deliver genetic material into human-targeted cells with minimal toxicity is an important challenge in the field. The present study reports the straightforward preparation and testing of a modular non-viral gene carrier based on AuNPs. The design, synthesis, and in vitro evaluation of multilayer gold nanoparticles (AuNPs) as non-viral gene carriers with high transfection efficiency, reduced cytotoxicity for targeted therapeutic delivery of nucleic acids to MCF-7 cancer cells are presented. The developed non-viral vector is based on supramolecular "host-guest" inclusion complexes of ß-cyclodextrin, positioned on the AuNPs surface over a layer of polyethyleneimine, and adamantyl moiety from polyethylene glycol conjugated decapeptide (WXEAAYQRFL). First, the ß-CD functionalized PEI was utilized as the template for the synthesis of AuNPs of controlled sizes. The reaction produced small AuNPs with a cationic layer which is known for efficient condensation of genetic material and ß-CD suitable for the decoration of the carrier with targeting moieties using "host-guest" inclusion complexation. Subsequently, adamantine-polyethylene glycol conjugated decapeptide was attached to the AuNPs. The in vitro results have validated the ability of the proposed systems to selectively target tumor cells with high efficacy and low toxicity due to the unique affinity of the aptamer-functionalized nanoparticles toward breast cancer cells. The findings of this work demonstrated that the proposed modular system may represent a very promising platform for the AuNP-based non-viral vectors mainly due to the versatility of the system, which allows for the facile exchange of several types of ligands for improving the targeting properties and transfection efficiency, or for providing better protection from the endocytotic systems.


Assuntos
Nanopartículas Metálicas , Neoplasias , Humanos , Células MCF-7 , Ouro/química , Nanopartículas Metálicas/química , Transfecção , Polietilenoglicóis/química
13.
Pharmaceutics ; 15(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37376122

RESUMO

The therapeutic efficiency of plant extracts has been limited by their poor pharmaceutical availability. Hydrogels have promising potential to be applied as wound dressings due to their high capacity to absorb exudates and their enhanced performance in loading and releasing plant extracts. In this work, pullulan/poly (vinyl alcohol) (P/PVA) hydrogels were first prepared using an eco-friendly method based on both a covalent and physical cross-linking approach. Then, the hydrogels were loaded with the hydroalcoholic extract of Calendula officinalis by a simple post-loading immersion method. Different loading capacities were investigated in terms of the physico-chemical properties, chemical composition, mechanical properties, and water absorption. The hydrogels exhibited high loading efficiency due to the hydrogen bonding interactions between polymer and extract. The water retention capacity as well as the mechanical properties decreased with the increase in the extract amount in hydrogel. However, higher amounts of extract in the hydrogel improved the bioadhesiveness. The release of extract from hydrogels was controlled by the Fickian diffusion mechanism. Extract-loaded hydrogels expressed high antioxidant activity, reaching 70% DPPH radical scavenging after 15 min immersion in buffer solution at pH 5.5. Additionally, loaded hydrogels showed a high antibacterial activity against Gram-positive and Gram-negative bacteria and were non-cytotoxic against HDFa cells.

14.
Future Med Chem ; 15(15): 1369-1391, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37577781

RESUMO

Aim: A series of new hybrid molecules with two iodine atoms on the sides were synthesized. Methods: A one-pot, two-component method with trifluoroacetic acid as an effective catalyst to obtain dihydro-pyrrol-2-one compounds was developed. Short reaction times, a cheap catalyst, high yields and clean work-up are benefits of this method. Results: The chemical structures of the newly synthesized compounds were verified through spectroscopic techniques. Their antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans was tested in vitro. Conclusion: NC- and OH- radicals confer broad-spectrum antimicrobial activity, including against Gram-positive and Gram-negative bacteria and yeasts. Compounds 3g >7 and >9 were most active on the two bacterial species, while 3l >9 and >3i were most active against the fungal strain.

15.
Antioxidants (Basel) ; 10(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067035

RESUMO

This study aimed to obtain and characterize extracted hemp oil enriched in cannabidiol (CBD) by decarboxylation of cannabidiolic acid (CBDA) and to give new insights into its antioxidant and anticancer effects. Optimization of CBDA decarboxylation in hemp oil was performed, and CBD and CBDA contents and purities were determined by flash chromatography, 1H- and 13C-NMR. The antioxidant properties of CBD-enriched oil were investigated by Fe2+ chelating activity, Fe3+ reducing antioxidant power assay, O2●- scavenging activity, HO● scavenging ability and lipid peroxidation inhibitory assay, and its cytotoxicity, apoptosis- and oxidative stress-inducing effects on NHDF, MeWo, HeLa, HepG2 and HOS cells were determined. The CBD concentration in hemp oil was increased by CBDA soft decarboxylation optimized at 90 °C, for 1 h and the resulting oil was capable of reducing iron, scavenging free radicals and inhibiting lipid peroxidation in cell-free oxidative conditions. CBD-enriched oil promoted NHDF proliferation at up to 15 µg CBD/mL, while inducing apoptosis and ROS production and modulating antioxidant enzymes' gene expression in cancer cells, being selective for osteosarcoma cells, and induced apoptosis by p53- and ROS-independent mechanisms. CBD-enriched hemp oil demonstrated antioxidant properties in oxidative conditions and promoted normal fibroblasts' proliferation, while inducing apoptosis and ROS production in cancer cells.

16.
J Mater Sci Mater Med ; 21(11): 3009-18, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20820886

RESUMO

Ketoprofen (Ket) was intercalated into layered double hydroxides (ZnAlLDH and MgAlLDH) using the ionic exchange method. The drug intercalation was confirmed by X-ray diffraction (XRD) and FTIR spectroscopy. Ket release from the inorganic matrix was studied at pH 7.4 in continuous regime with a flow rate of 0.5 and respectively 1.0 ml/min. The kinetical data were interpreted using the Ritger and Peppas model. The data prove that the release kinetics and mechanism depend on the eluent flow rate. Quantification of gastric tolerance shows that the ulcerogenic effect of the intercalated drug is lower than the one of the raw Ket. The antinociceptive effect of both formulations was studied by the hot-plate method performed on mice. The MgAlLDH_Ket formulation shows a tendency towards a stronger antinociceptive effect than its ZnAlLDH_Ket counterpart during the 210 min recorded period.


Assuntos
Química Farmacêutica/métodos , Portadores de Fármacos/química , Hidróxidos/química , Cetoprofeno/farmacocinética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacocinética , Portadores de Fármacos/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Hidróxidos/metabolismo , Cetoprofeno/administração & dosagem , Cetoprofeno/efeitos adversos , Masculino , Camundongos , Medição da Dor , Polímeros/química , Polímeros/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/epidemiologia , Resultado do Tratamento , Difração de Raios X
17.
J Ethnopharmacol ; 252: 112559, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31935497

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Crataegus leaves, flowers and fruits have been traditionally used to improve blood circulation, numerous preclinical and clinical studies supporting the cardiovascular benefits of Crataegus preparations. In this respect, there is very limited data on Crataegus pentagyna; in addition, the chemical profile of this species is still incompletely elucidated. AIM OF THE STUDY: The objective of this study was to examine the cardiovascular benefits of Crataegus pentagyna Waldst. et Kit. ex Willd. (small-flowered black hawthorn, Rosaceae) extracts (leaf, flower and fruit ethyl acetate extracts) and the underlying mechanisms. We hypothesized that C. pentagyna extracts might exert vasodilatory effects and inhibit arginase activity due, in large part, to their polyphenolic constituents. MATERIALS AND METHODS: C. pentagyna extracts induced-relaxation and the mechanisms involved were studied ex vivo in isolated aortic rings from Sprague-Dawley rats. The inhibitory effects on bovine liver arginase I were assessed by an in vitro assay. Metabolite profiling of C. pentagyna extracts was performed and the most endothelium- and nitric oxide synthase-dependent; flower extract additionally reduced Ca2+ entry and, to a lesser extent, Ca2+ release from the sarcoplasmic reticulum. C. pentagyna proved to be an important source of arginase inhibitors with potential benefits in endothelial dysfunction that remains to be explored.


Assuntos
Aorta Torácica/efeitos dos fármacos , Arginase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta Torácica/fisiologia , Cálcio/fisiologia , Crataegus , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Flores , Frutas , Masculino , Folhas de Planta , Canais de Potássio/fisiologia , Ratos Sprague-Dawley
18.
Sci Rep ; 10(1): 6591, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313258

RESUMO

The paper aims to investigate the cytotoxic effect on tumor cells of irradiated AuNPs in green light and subsequently functionalized with HS-PEG-NH2. The toxicity level of gold conjugates after their functionalization with DOX and TAT peptide was also evaluated. The AuNPs were prepared using the modified Turkevich method and exposed to visible light at a wavelength of 520 nm prior their PEGylation. The optical properties were analyzed by UV-vis spectroscopy, the surface modification was investigated using FTIR and XPS spectroscopies and their sizes and morphologies were evaluated by TEM and DLS techniques. DOX and TAT peptide were linked to the surface of PEGylated AuNPs by reacting their amino groups with glycidyloxypropyl of PEGylated DOX or TAT conjugates under mild conditions at room temperature and in the presence of ethanol as catalyst. The conjugates containing DOX or DOX and TAT have been characterized by fluorescence and FTIR techniques. The changes of electrochemical features were observed using cyclic voltammetry, suggesting a better stability of irradiated nanoparticles. By mass spectrometry it was confirmed that the compounds of interest were obtained. The cell viability test showed that irradiated and non-irradiated nanoparticles coated with PEG are not toxic in normal cells. Tumor cell viability analysis showed that the PEGylated nanoparticles modified with DOX and TAT peptide were more effective than pristine DOX, indicating cytotoxicity up to 10% higher than non-irradiated ones.


Assuntos
Doxorrubicina/farmacologia , Produtos do Gene tat/farmacologia , Nanopartículas Metálicas/química , Osteossarcoma/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Produtos do Gene tat/química , Ouro/química , Humanos , Osteossarcoma/genética , Osteossarcoma/patologia , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Int J Biol Macromol ; 131: 134-146, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30857965

RESUMO

Currently, biosorption is considered a leading-edge environmentally-friendly method for the low-cost remediation of wastewaters contaminated with metal ions. However, the safe disposal of metal-loaded biosorbents is still a challenging issue. In this context, our major objective was to explore the possibility of "waste minimization" by reusing the metal-loaded biosorbents in further environmental applications, particularly into the oxidative catalysis of dyes. Thus, the decolourisation efficiency (DE) of Methyl Orange (MO) in aqueous solutions under ambient light using copper-imprinted chitosan-based composites in comparison to non-imprinted ones was investigated in this work. The MO degradation was established first in the absence of any co-catalyst, when a DE value of 95.3% was achieved by the ion-imprinted catalysts within 360 min of reaction, compared to only 67.4% attained by the non-imprinted ones. Under Fenton-like conditions, the apparent degradation rate constant was seventy times higher, the DE increasing within 40 min to about 98.6%, and 70.5% respectively, whereas the content of co-catalyst (H2O2) was significantly lowered compared to other reported studies. The straightforward preparation of copper-loaded composites, along with their excellent stability and high efficiency even after four consecutive reaction runs support our ion-imprinted systems as potential catalysts for dye removal by oxidative decolourisation treatments.


Assuntos
Quitosana/química , Cobre/química , Íons/química , Nanoestruturas/química , Adsorção , Algoritmos , Catálise , Modelos Teóricos , Nanoestruturas/ultraestrutura , Porosidade , Análise Espectral , Poluentes Químicos da Água/química , Purificação da Água
20.
Environ Sci Pollut Res Int ; 26(19): 19684-19696, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31081534

RESUMO

Doxorubicin (DOX) is a chemotherapeutic agent from anthracycline class, which acts unselectively on all cells; thus, it may have genotoxic and/or mutagenic effects and cause serious environmental problems. Herein, the decomposition of a diluted solution of DOX hydrochloride for injection has been investigated under photo-oxidative conditions, in ambient light and without pH modification, using hydrogen peroxide as oxidizing agent and hydrophobic siloxane-based metal-organic frameworks (MOFs) as heterogeneous catalysts. The kinetics of the photodegradation process was followed by UV-Vis spectroscopy and by ESI-MS. According to UV-Vis data, two pseudo-first-order kinetic steps describe the process, with rate constants in the order of 10-3-10-2 min-1 for the rate-determining one. ESI-MS provided more accurate information, with a rate constant of 2.6 · 10-2 min-1 calculated from the variation of DOX ion abundance. Complete decomposition of DOX was achieved after 120 min in the shade and after only 20 min by exposure to sunlight. The analysis of the residual waters by mass spectrometry and 1D and 2D NMR spectroscopy showed complete disappearance of DOX in all cases, excluded any anthracycline species, which are destroyed in the tested conditions, and proved formation of an un-harmful compound-glycerol, while no trace of metal was detected by XRF. Preliminary data also showed decomposition of oxytetracycline in similar conditions. By this study, we bring into attention a less-addressed pollution issue and we propose a mild and effective method for the removal of drug emerging pollutants.


Assuntos
Doxorrubicina/análise , Luz , Estruturas Metalorgânicas/química , Fotólise , Siloxanas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Doxorrubicina/efeitos da radiação , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Oxidantes/química , Oxirredução , Poluentes Químicos da Água/efeitos da radiação
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