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1.
Dalton Trans ; 53(26): 10928-10937, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38888155

RESUMO

Multifunctional materials that combine antimicrobial properties with the ability to stimulate bone formation are needed to overcome the problem of infected bone defects. As a novel approach, a new composite based on bioactive glass nanoparticles in a simple system of SiO2-CaO (BG) coated with NH4[Cu3(µ3-OH)(µ3-4-carboxypyrazolato)3] (Cu-MOF) with additionally anchored silver nanoparticles (AgNPs) was proposed. Ag@Cu-MOF@BG obtained by the spin coating approach in the form of a disc was characterized using PXRD, ATR-FTIR, XPS, ICP-OES, and TEM. Importantly, the material retained its bioactivity, although ion exchange in the bioactive glass administered as a disc is limited. Hydroxyapatite (HA) formation was identified in TEM images after 7 days of immersion of the composite in a physiological-like buffer (pH 7.4, 37 °C). The Cu and Ag contents of Ag@Cu-MOF@BG were as low as 0.013 and 0.018 wt% respectively, but the slow release of the AgNPs ensured its antibacterial nature. Ag@Cu-MOF@BG exhibited antibacterial activity against all tested bacteria (E. coli, S. aureus, P. aeruginosa, and K. pneumoniae) with the diameter of the inhibition zones of their growth between 8 and 10 mm and the reduction index determined to be ≥3. Moreover, the biocompatibility of the new composite has been demonstrated, as shown by cell culture assays with human dermal fibroblasts (HDFs). The results from the migration test also proved that the HDF cell's phenotypic properties were not changed, and the cell adhesion and migration ability were the same as in control indirect assays.


Assuntos
Antibacterianos , Materiais Biocompatíveis , Vidro , Nanopartículas Metálicas , Estruturas Metalorgânicas , Testes de Sensibilidade Microbiana , Prata , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Vidro/química , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Cobre/química , Cobre/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos
2.
Biomedicines ; 12(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38927517

RESUMO

The prevalence of autism spectrum disorder (ASD) is still increasing, which means that this neurodevelopmental lifelong pathology requires special scientific attention and efforts focused on developing novel therapeutic approaches. It has become increasingly evident that neuroinflammation and dysregulation of neuro-immune cross-talk are specific hallmarks of ASD, offering the possibility to treat these disorders by factors modulating neuro-immunological interactions. Mesenchymal stem cell-based therapy has already been postulated as one of the therapeutic approaches for ASD; however, less is known about the molecular mechanisms of stem cell influence. One of the possibilities, although still underestimated, is the paracrine purinergic activity of MSCs, by which stem cells ameliorate inflammatory reactions. Modulation of adenosine signaling may help restore neurotransmitter balance, reduce neuroinflammation, and improve overall brain function in individuals with ASD. In our review article, we present a novel insight into purinergic signaling, including but not limited to the adenosinergic pathway and its role in neuroinflammation and neuro-immune cross-talk modulation. We anticipate that by achieving a greater understanding of the purinergic signaling contribution to ASD and related disorders, novel therapeutic strategies may be devised for patients with autism in the near future.

3.
RSC Adv ; 13(43): 30108-30117, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849700

RESUMO

Multi-wall carbon nanotube (MWCNT) coatings are gaining increasing interest because of their special properties used in many science fields. The titania coatings are known for their improvement of osteoblast adhesion, thus changing the surface architecture. Bi-layer coatings comprising 0.25 wt% of the MWCNTs and 0.30 wt% of titania (anatase structure) were synthesized in a two-stage procedure using the electrophoretic deposition method (EPD). The MWCNT and TiO2 coatings were deposited with voltage and time parameters, respectively, of 20 V and 0.5 min, and 50 V and 4 min. EDS, AFM, SEM, Raman spectroscopy, nano-scratch test, potentiodynamic corrosion tests, wettability studies, and cytotoxicity determined with MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test on human dermal fibroblasts (HDF) and mouse osteoblast precursors (MC3T3), and lactate dehydrogenase (LDH) activity test were carried out on examined surfaces. The prepared MWCNT/TiO2 coating is uniformly distributed by MWCNTs and agglomerated by TiO2 particles of size ranging from 0.1 to 3 µm. Raman spectroscopy confirmed the anatase structure of the TiO2 addition and showed typical peaks of the MWCNTs. The MWCNT/TiO2 coating had higher roughness, higher adhesion strength, and improved corrosion resistance compared to the MWCNT basic coating. The results of biological tests proved that physicochemical properties of the surface, such as high porosity and wettability of MWCNT/TiO2-coated material, would support cell adhesion, but toxic species could be released to the culture medium, thus resulting in a decrease in proliferation.

4.
Int J Mol Sci ; 24(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37628848

RESUMO

Non-thermal plasma (NTP) application in medicine is a dynamically developing interdisciplinary field. Despite the fact that basics of the plasma phenomenon have been known since the 19th century, growing scientific attention has been paid in recent years to the use of plasma in medicine. Three most important plasma-based effects are pivotal for medical applications: (i) inactivation of a broad spectrum of microorganisms, (ii) stimulation of cell proliferation and angiogenesis with lower plasma treatment intensity, and (iii) inactivation of cells by initialization of cell death with higher plasma intensity. In this review, we explain the underlying chemical processes and reactive species involvement during NTP in human (or animal) tissues, as well as in bacteria inactivation, which leads to sterilization and indirectly supports wound healing. In addition, plasma-mediated modifications of medical surfaces, such as surgical instruments or implants, are described. This review focuses on the existing knowledge on NTP-based in vitro and in vivo studies and highlights potential opportunities for the development of novel therapeutic methods. A full understanding of the NTP mechanisms of action is urgently needed for the further development of modern plasma-based medicine.


Assuntos
Medicina , Gases em Plasma , Animais , Humanos , Morte Celular , Proliferação de Células , Estudos Interdisciplinares , Plasma , Gases em Plasma/farmacologia , Gases em Plasma/uso terapêutico
5.
ACS Biomater Sci Eng ; 9(8): 4646-4653, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37526989

RESUMO

A novel composite based on biocompatible hydroxyapatite (HA) nanoparticles and Cu-HKUST-1 (Cu-HKUST-1@HA) has been prepared following a layer-by-layer strategy. Cu-HKUST-1 was carefully selected from a group of four Cu-based metal-organic frameworks as the material with the most promising antimicrobial activity. The formation of a colloidal Cu-HKUST-1 layer on HA nanoparticles was confirmed by various techniques, e.g., infrared spectroscopy, powder X-ray diffraction, N2 sorption, transmission electron microscopy imaging, electron paramagnetic resonance, and X-ray absorption spectroscopy. Importantly, such a Cu-HKUST-1 layer significantly improved the nanomechanical properties of the composite, with Young's modulus equal to that of human cortical bone (13.76 GPa). At the same time, Cu-HKUST-1@HA has maintained the negative zeta potential (-16.3 mV in pH 7.4) and revealed biocompatibility toward human dermal fibroblasts up to a concentration of 1000 µg/mL, without inducing ex vivo hemolysis. Chemical stability studies of the composite over 21 days in a buffer-simulated physiological fluid allowed a detailed understanding of the transformations that the Cu-HKUST-1@HA undergoes over time. Finally, it has been confirmed that the Cu-HKUST-1 layer provides antibacterial properties to HA, and the synergism reached in this way makes it promising for bone tissue regeneration.


Assuntos
Durapatita , Estruturas Metalorgânicas , Humanos , Durapatita/farmacologia , Durapatita/química , Estruturas Metalorgânicas/química , Osso e Ossos , Regeneração Óssea
6.
J Biomed Mater Res A ; 111(10): 1565-1576, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37162101

RESUMO

Purinergic signaling, the oldest evolutionary transmitter system, has been increasingly studied as a pivotal target for novel anti-cancer therapies. In the present work, the developed nanobiocatalytic system consisting of adenylate kinase immobilized on graphene oxide (AK-GO) was characterized in terms of its physicochemical and biochemical properties. We put special emphasis on the AK-GO influence on purinergic signaling components, that is, ecto-nucleotides concentration and ecto-enzymes expression and activity in human lung carcinoma epithelial (A549) cells. The immobilization-dependent modification of AK kinetic parameters allowed for the removal of ATP excess while maintaining low ATP concentrations, efficient decrease in adenosine concentration, and control of the nucleotide balance in carcinoma cells. The cyto- and hemocompatibility of developed AK-GO nanobiocatalytic system indicates that it can be successfully harnessed for biomedical applications. In A549 cells treated with AK-GO nanobiocatalytic system, the significantly decreased adenosinergic signaling results in reduction of the proliferation and migration capability of cancer cells. This finding is particularly relevant in regard to AK-GO prospective anti-cancer applications.


Assuntos
Adenilato Quinase , Carcinoma , Humanos , Adenilato Quinase/metabolismo , Células Epiteliais/metabolismo , Trifosfato de Adenosina/metabolismo , Pulmão/metabolismo
7.
Cell Signal ; 106: 110641, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36858191

RESUMO

The purinergic signaling pathway is the oldest evolutionary transmitter system that regulates a wide array of physiological and pathophysiological processes in central nervous system. However, the question of how the purinergic compounds interact with administrated drugs is rarely addressed. We aimed to clarify the interplay between purinergic signaling and chemotherapeutic drug temozolomide (TMZ) in human glioma cell line. We applied an initial retinoic acid-induced differentiation of A172 glioma cells and tested the P2X7 receptor expression in undifferentiated and differentiated gliomas. We compared the P2X7 receptor agonists/antagonists influence and their co-action with TMZ in both cell types through assessment of cell proliferation, viability and migrative properties. Molecular docking allowed to indicate the potential binding site for TMZ in the structure of hP2X7 receptor. Differentiated cells turned out to be more susceptible to ATP and TMZ alone but also to the concerted action of TMZ and ATP. Enhanced effects triggered by ATP and TMZ treatment include the decreased by 70% viability, and reduced migration ability of differentiated A172 glioma cells. Noteworthy, these results can be achieved already at low non-toxic ATP concentration and at reduced to 125 µM effective concentration of TMZ. Therefore, ATP molecules must be present and maintained at appropriate concentration in glioma cells microenvironment to achieve their co-action with TMZ and enhanced anti-cancer activity. All that, in turn, could shorten the therapy, increase its efficacy and limit the side effects for the patient. Our purinergic approach creates a promising perspective for developing novel combined oncological therapies.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Receptores Purinérgicos P2X7/uso terapêutico , Simulação de Acoplamento Molecular , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Trifosfato de Adenosina , Linhagem Celular Tumoral , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Apoptose , Microambiente Tumoral
8.
J Funct Biomater ; 13(4)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36547531

RESUMO

Hydroxyapatite (HA) layers are appropriate biomaterials for use in the modification of the surface of implants produced inter alia from a Ti6Al4V alloy. The issue that must be solved is to provide implants with appropriate biointegration properties, enabling the permanent link between them and bone tissues, which is not so easy with the HA layer. Our proposition is the use of the intermediate layer ((IL) = TiO2, and titanate layers) to successfully link the HA coating to a metal substrate (Ti6Al4V). The morphology, structure, and chemical composition of Ti6Al4V/IL/HA systems were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectrometry (EDS). We evaluated the apatite-forming ability on the surface of the layer in simulated body fluid. We investigated the effects of the obtained systems on the viability and growth of human MG-63 osteoblast-like cells, mouse L929 fibroblasts, and adipose-derived human mesenchymal stem cells (ADSCs) in vitro, as well as on their osteogenic properties. Based on the obtained results, we can conclude that both investigated systems reflect the physiological environment of bone tissue and create a biocompatible surface supporting cell growth. However, the nanoporous TiO2 intermediate layer with osteogenesis-supportive activity seems most promising for the practical application of Ti6Al4V/TiO2/HA as a system of bone tissue regeneration.

9.
Colloids Surf B Biointerfaces ; 220: 112919, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36252539

RESUMO

Rapid growth in the mass production of nanomaterials together with their abundant use in consumer products, progressively increases the potential risks of living organisms exposure. Some unique properties of nanomaterials and nanoparticles facilitate their interactions with biomolecules (nano-bio interactions). The purinergic signalling system is one of the oldest evolutionary and widespread transmitter system that utilizes extracellular purine nucleotides and nucleosides as chemical messengers. However, interactions between nanomaterials and components of purinergic signalling pathway have not been fully recognized so far. In view of the emerging data, we summarize the current state-of-art and present the perspectives of nanomaterials influence on the functions of purinergic signaling pathway in different types of cells. The described nano-bio interactions include inter alia direct interplay with purinergic receptors or altering receptor genes expression, activation of inflammatory processes, and induction of cell death. However, the precise mechanisms are yet still to be disentangled. Due to the fact that majority of the effects ascribed to nanomaterials seems to induce disordered signalling, these interactions cannot stay neglected. A better understanding of signalling modulations induced by nanomaterials is not only essential for the accurate assessment of their toxicity, but also for synthesis and design of novel, safer nanomaterials.


Assuntos
Nanopartículas , Nanoestruturas , Receptores Purinérgicos/metabolismo , Purinas/metabolismo , Nanoestruturas/química , Transdução de Sinais , Nanopartículas/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-35696424

RESUMO

Increasing interest has been shown in phenolic compounds for enhancing food quality, but their hydrophilicity restricts application in lipophilic systems. Therefore, in this study, twelve hydroxycinnamates derivatives (alkyl and steryl esters of sinapic acid (SA), caffeic acid (CA), and ferulic acid [FA]) were synthesised and evaluated for antioxidant and cytotoxic characteristics. CA esters had the highest radical scavenging activity (RSA) analysed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. Values of inhibitory concentration (IC50) of synthesised compounds were related to their structure and lipophilicity. The effect of these hydroxycinnamic acid esters on the antioxidant potential of real samples (rapeseed oil, margarine and mayonnaise) was estimated. None of the investigated derivatives significantly affected the viability of the model intestinal cells Caco2, while the octyl esters demonstrated a toxic effect at low concentrations. The synthesised esters exerted cytotoxic and anti-proliferative effects against transformed cell lines (HeLa and A549). Octyl esters were potent anticancer compounds on two human cancer cell lines. The synthesised phenolipids, as valuable and safe antioxidant additives, can find broader applications in the production of fat-based products to prevent oxidation processes, extend their shelf life and improve quality.


Assuntos
Antioxidantes , Aditivos Alimentares , Antioxidantes/química , Antioxidantes/farmacologia , Células CACO-2 , Ésteres/química , Aditivos Alimentares/análise , Aditivos Alimentares/farmacologia , Humanos , Oxirredução , Fenóis/análise
11.
Int J Mol Sci ; 23(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35269599

RESUMO

Titanium dioxide is one of the best described photosensitive materials used in photocatalysis, solar cells, self-cleaning coatings, and sunscreens. The scientific and industrial attention has been focused on the highly photoactive crystalline phase of titanium dioxide (TiO2). It is commonly accepted that the smaller TiO2 particles, the higher photoactivity they present. Therefore, titanium dioxide nanoparticles are massively produced and widely used in everyday products. The amorphous phase of titanium dioxide has been treated with neglect, as the lack of its photocatalytic properties is assumed in advance. In this work, the complex experimental proof of the UV-protective properties of the nano-sized amorphous TiO2 phase is reported. Amorphous n-TiO2 is characterized by photocatalytic inactivity and, as a consequence, low cytotoxicity to fibroblast cells. When exposed to UV radiation, cells with amorphous TiO2 better survive under stress conditions. Thus, we postulate that amorphous n-TiO2 will be more beneficial and completely safe for cosmetic applications. Moreover, the results from in situ FTIR studies let us correlate the low toxicity of amorphous samples with low ability to form hydroperoxo surface species.


Assuntos
Cosméticos , Nanopartículas , Nanopartículas/química , Titânio/química , Raios Ultravioleta
12.
Nanoscale ; 14(14): 5514-5528, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35343556

RESUMO

A highly bioactive glass solvBG76 in a binary system 76SiO2-24CaO (wt%) was prepared following a solvothermal path of the synthesis. The facile synthesis, in terms of the steps and reagents needed, enabled the achievement of a mesoporous material. Many factors such as nano-size (<50 nm), different morphology (non-spherical), use of an unconventional network modifier (calcium hydroxide) during the synthesis, a structure free of crystalline impurities, and textural properties greatly enhanced the kinetic deposition process of hydroxyapatite (HA) when contacting with physiological fluids. The formation of a HA layer on the glass was analyzed by various techniques, namely XRD, IR-ATR, Raman, XPS, EDS analyses, SEM, and HR-TEM imaging. The results obtained were compared to the 45S5 glass tested as a reference biomaterial as well as 70S30C-a glass with similar size and composition to reported solvBG76 but obtained by the conventional sol-gel method. For the first time, superior apatite-mineralization ability in less than 1 h in a physiological-like buffer was achieved. This unique bioactivity is accompanied by biocompatibility and hemocompatibility, which was indicated by a set of various assays in human dermal fibroblasts and MC3T3 mouse osteoblast precursor cells, as well as hemolytic activity determination.


Assuntos
Durapatita , Vidro , Animais , Apatitas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Durapatita/química , Vidro/química , Camundongos
13.
Molecules ; 27(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209155

RESUMO

Chemotherapy is one of the most commonly used methods of cancer disease treatment. Due to the acquisition of drug resistance and the possibility of cancer recurrence, there is an urgent need to search for new molecules that would be more effective in destroying cancer cells. In this study, 1-(benzofuran-2-yl)ethan-1-one oxime and 26 oxime ethers containing heterocyclic, alicyclic or aromatic moiety were screened for their cytotoxicity against HeLa cancer cell line. The most promising derivatives with potential antitumor activity were 2-(cyclohexylideneaminoxy)acetic acid (18) and (E)-acetophenone O-2-morpholinoethyl oxime (22), which reduced the viability of HeLa cells below 20% of control at concentrations of 100-250 µg/mL. Some oxime ethers, namely thiazole and benzothiophene derivatives (24-27), also reduced HeLa cell viability at similar concentrations but with lower efficiency. Further cytotoxicity evaluation confirmed the specific toxicity of (E)-acetophenone O-2-morpholinoethyl oxime (22) against A-549, Caco-2, and HeLa cancer cells, with an EC50 around 7 µg/mL (30 µM). The most potent and specific compound was (E)-1-(benzothiophene-2-yl)ethanone O-4-methoxybenzyl oxime (27), which was selective for Caco-2 (with EC50 116 µg/mL) and HeLa (with EC50 28 µg/mL) cells. Considering the bioavailability parameters, the tested derivatives meet the criteria for good absorption and permeation. The presented results allow us to conclude that oxime ethers deserve more scientific attention and further research on their chemotherapeutic activity.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Éteres/química , Oximas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Análise Espectral , Relação Estrutura-Atividade
14.
J Phys Chem B ; 126(4): 928-933, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35077166

RESUMO

The interaction between graphene oxide (GO) and lysozyme (LYZ) in aqueous solution was investigated for GO specific surface area determination and for the thermodynamic description of the process. It was experimentally proved that LYZ is a much better adsorbate than the most common methylene blue, allowing the determination of genuine GO surface area. Our fluorescence spectroscopy results indicate that LYZ molecules interact with GO at high- and low-affinity sites depending on the surface coverage, reflecting the protein mono- and multilayer formation, respectively. The lack of the secondary structure changes confirms LYZ usability as a model adsorbate. The calculated values of thermodynamic parameters (Δ(ΔH0) = -195.0 kJ/mol and Δ(ΔS0) = -621.3 J/molK) indicate that the interactions are exothermic, enthalpy-driven. All the reported results reveal the physical nature of the LYZ-GO interaction at the studied concentration ratios.


Assuntos
Grafite , Muramidase , Adsorção , Grafite/química , Muramidase/química , Termodinâmica
15.
Materials (Basel) ; 14(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34771955

RESUMO

Chitosan is a valuable, functional, and biodegradable polysaccharide that can be modified to expand its applications. This work aimed to obtain chitosan derivatives with fluorescent properties. Three heterocyclic aromatic dyes (based on benzimidazole, benzoxazole, and benzothiazole) were synthesized and used for the chemical modification of chitosan. Emission spectroscopy revealed the strong fluorescent properties of the obtained chitosan derivatives even at a low N-substitution degree of the dye. The effect of high-energy ultraviolet radiation (UV-C) on modified chitosan samples was studied in solution with UV-Vis spectroscopy and in the solid state with FTIR spectroscopy. Moreover, cytotoxicity towards three different cell types was evaluated to estimate the possibilities of biomedical applications of such fluorescent chitosan-based materials. It was found that the three new derivatives of chitosan were characterized by good resistance to UV-C, which suggests the possibility of using these materials in medicine and various industrial sectors.

16.
Int J Mol Sci ; 22(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34681820

RESUMO

The existing clinical protocols of hepatoma treatment require improvement of drug efficacy that can be achieved by harnessing nanomedicine. Porphyrin-based, paddle-wheel framework (PPF) structures were obtained and tested as dual-kinetic Sorafenib (SOR) nanocarriers against hepatoma. We experimentally proved that sloughing of PPF structures combined with gradual dissolving are effective mechanisms for releasing the drug from the nanocarrier. By controlling the PPF degradation and size of adsorbed SOR deposits, we were able to augment SOR anticancer effects, both in vitro and in vivo, due to the dual kinetic behavior of SOR@PPF. Obtained drug delivery systems with slow and fast release of SOR influenced effectively, although in a different way, the cancer cells proliferation (reflected with EC50 and ERK 1/2 phosphorylation level). The in vivo studies proved that fast-released SOR@PPF reduces the tumor size considerably, while the slow-released SOR@PPF much better prevents from lymph nodes involvement and distant metastases.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Hepáticas/tratamento farmacológico , Estruturas Metalorgânicas/uso terapêutico , Porfirinas/uso terapêutico , Sorafenibe/uso terapêutico , Animais , Antineoplásicos/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Liberação Controlada de Fármacos , Humanos , Sistema de Sinalização das MAP Quinases , Nanomedicina , Fosforilação , Ratos , Ratos Sprague-Dawley
17.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360901

RESUMO

The oxidative properties of nanomaterials arouse legitimate concerns about oxidative damage in biological systems. On the other hand, the undisputable benefits of nanomaterials promote them for biomedical applications; thus, the strategies to reduce oxidative potential are urgently needed. We aimed at analysis of nitrogen-containing carbon quantum dots (N-CQDs) in terms of their biocompatibility and internalization by different cells. Surprisingly, N-CQD uptake does not contribute to the increased oxidative stress inside cells and lacks cytotoxic influence even at high concentrations, primarily through protein corona formation. We proved experimentally that the protein coating effectively limits the oxidative capacity of N-CQDs. Thus, N-CQDs served as an immobilization support for three different enzymes with the potential to be used as therapeutics. Various kinetic parameters of immobilized enzymes were analyzed. Regardless of the enzyme structure and type of reaction catalyzed, adsorption on the nanocarrier resulted in increased catalytic efficiency. The enzymatic-protein-to-nanomaterial ratio is the pivotal factor determining the course of kinetic parameter changes that can be tailored for enzyme application. We conclude that the above properties of N-CQDs make them an ideal support for enzymatic drugs required for multiple biomedical applications, including personalized medical therapies.


Assuntos
Biocatálise , Carbono/química , Carbono/farmacologia , Nitrogênio/química , Nitrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Coroa de Proteína/metabolismo , Pontos Quânticos/química , Pontos Quânticos/metabolismo , Células A549 , Animais , Apirase/química , Apirase/farmacologia , Catalase/química , Catalase/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia , Células HeLa , Humanos , Ratos , Espécies Reativas de Oxigênio/metabolismo , beta-Galactosidase/química , beta-Galactosidase/farmacologia
18.
Materials (Basel) ; 14(9)2021 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-34065161

RESUMO

Carbon-based quantum dots are widely suggested as fluorescent carriers of drugs, genes or other bioactive molecules. In this work, we thoroughly examine the easy-to-obtain, biocompatible, nitrogen-containing carbonaceous quantum dots (N-CQDs) with stable fluorescent properties that are resistant to wide-range pH changes. Moreover, we explain the mechanism of fluorescence quenching at extreme pH conditions. Our in vitro results indicate that N-CQDs penetrate the cell membrane; however, fluorescence intensity measured inside the cells was lower than expected from carbonaceous dots extracellular concentration decrease. We studied the mechanism of quenching and identified reduced form of ß-nicotinamide adenine dinucleotide (NADH) as one of the intracellular quenchers. We proved it experimentally that the elucidated redox process triggers the efficient reduction of amide functionalities to non-fluorescent amines on carbonaceous dots surface. We determined the 5 nm-wide reactive redox zone around the N-CQD surface. The better understanding of fluorescence quenching will help to accurately quantify and dose the internalized carbonaceous quantum dots for biomedical applications.

19.
Materials (Basel) ; 14(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801874

RESUMO

Graphene oxide (GO) is one of the most exciting and widely used materials. A new method of nanographene oxide (n-GO) formation is presented. The described unique sequence of ultrasonication in dimethyl sulfoxide solution allows us to obtain different sizes of n-GO sheets by controlling the timing of the cutting and re-aggregation processes. The obtained n-GO exhibits only minor spectral changes, mainly due to the formation of S-containing surface groups; thus, it can be concluded that the material is not reduced during the process. Maintaining the initial oxygen functionalities together with the required nano-size (down to 200 nm) and high homogeneity are beneficial for extensive applications of n-GO. Moreover, we prove that the obtained material is evidently biocompatible. The calculated half-maximal effective concentration (EC50) increases by 5-fold, i.e., from 50 to 250 µg/mL, when GO is converted to n-GO. As a consequence, the new n-GO neither disturbs blood flow even in the narrowest capillaries nor triggers a toxic influence in surrounding cells. Thus, it can be a serious candidate for drugs and biomolecule carriers administered systemically.

20.
Med Res Rev ; 41(4): 2316-2349, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33645857

RESUMO

Mesenchymal stem cells (MSCs) play an important role in tissue homeostasis and damage repair through their ability to differentiate into cells of different tissues, trophic support, and immunomodulation. These properties made them attractive for clinical applications in regenerative medicine, immune disorders, and cell transplantation. However, despite multiple preclinical and clinical studies demonstrating beneficial effects of MSCs, their native identity and mechanisms of action remain inconclusive. Since its discovery, the CD73/ecto-5'-nucleotidase is known as a classic marker for MSCs, but its role goes far beyond a phenotypic characterization antigen. CD73 contributes to adenosine production, therefore, is an essential component of purinergic signaling, a pathway composed of different nucleotides and nucleosides, which concentrations are finely regulated by the ectoenzymes and receptors. Thus, purinergic signaling controls pathophysiological functions such as proliferation, migration, cell fate, and immune responses. Despite the remarkable progress already achieved in considering adenosinergic pathway as a therapeutic target in different pathologies, its role is not fully explored in the context of the therapeutic functions of MSCs. Therefore, in this review, we provide an overview of the role of CD73 and adenosine-mediated signaling in the functions ascribed to MSCs, such as homing and proliferation, cell differentiation, and immunomodulation. Additionally, we will discuss the pathophysiological role of MSCs, via CD73 and adenosine, in different diseases, as well as in tumor development and progression. A better understanding of the adenosinergic pathway in the regulation of MSCs functions will help to provide improved therapeutic strategies applicable in regenerative medicine.


Assuntos
Células-Tronco Mesenquimais , 5'-Nucleotidase/metabolismo , Adenosina , Diferenciação Celular , Imunomodulação , Transdução de Sinais
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