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1.
Anal Chem ; 96(1): 127-136, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38126724

RESUMO

In vitro/in vivo detection of copper ions is a challenging task but one which is important in the development of new approaches to the diagnosis and treatment of cancer and hereditary diseases such as Alzheimer's, Wilson's, etc. In this paper, we present a nanopipette sensor capable of measuring Cu2+ ions with a linear range from 0.1 to 10 µM in vitro and in vivo. Using the gold-modified nanopipette sensor with a copper chelating ligand, we evaluated the accumulation ability of the liposomal form of an anticancer Cu-containing complex at three levels of biological organization. First, we detected Cu2+ ions in a single cell model of human breast adenocarcinoma MCF-7 and in murine melanoma B16 cells. The insertion of the nanoelectrode did not result in leakage of the cell membrane. We then evaluated the distribution of the Cu-complex in MCF-7 tumor spheroids and found that the diffusion-limited accumulation was a function of the depth, typical for 3D culture. Finally, we demonstrated the use of the sensor for Cu2+ ion detection in the brain of an APP/PS1 transgenic mouse model of Alzheimer's disease and tumor-bearing mice in response to injection (2 mg kg-1) of the liposomal form of the anticancer Cu-containing complex. Enhanced stability and selectivity, as well as distinct copper oxidation peaks, confirmed that the developed sensor is a promising tool for testing various types of biological systems. In summary, this research has demonstrated a minimally invasive electrochemical technique with high temporal resolution that can be used for the study of metabolism of copper or copper-based drugs in vitro and in vivo.


Assuntos
Doença de Alzheimer , Neoplasias , Camundongos , Humanos , Animais , Cobre , Doença de Alzheimer/diagnóstico , Íons , Técnicas Eletroquímicas
2.
Biomacromolecules ; 24(11): 4532-4552, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37812143

RESUMO

Efficient cellular alignment in biomaterials presents a considerable challenge, demanding the refinement of appropriate material morphologies, while ensuring effective cell-surface interactions. To address this, biomaterials are continuously researched with diverse coatings, hydrogels, and polymeric surfaces. In this context, we investigate the influence of physicochemical parameters on the architecture of fibrillar hydrogels that significantly orient the topography of flexible hydrogel substrates, thereby fostering cellular adhesion and spatial organization. Our Review comprehensively assesses various techniques for aligning polymer fibrils within hydrogels, specifically interventions applied during and after the cross-linking process. These methodologies include mechanical strains, precise temperature modulation, controlled fluidic dynamics, and chemical modulators, as well as the use of magnetic and electric fields. We highlight the intrinsic appeal of these methodologies in fabricating cell-aligning interfaces and discuss their potential implications within the fields of biomaterials and tissue engineering, particularly concerning the pursuit of optimal cellular alignment.


Assuntos
Hidrogéis , Engenharia Tecidual , Engenharia Tecidual/métodos , Hidrogéis/farmacologia , Materiais Biocompatíveis/farmacologia , Polímeros/farmacologia , Adesão Celular
3.
Int J Mol Sci ; 24(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37445751

RESUMO

Frontiers in theranostics are driving the demand for multifunctional nanoagents. Upconversion nanoparticle (UCNP)-based systems activated by near-infrared (NIR) light deeply penetrating biotissue are a powerful tool for the simultaneous diagnosis and therapy of cancer. The intercalation into large polymer micelles of poly(maleic anhydride-alt-1-octadecene) provided the creation of biocompatible UCNPs. The intrinsic properties of UCNPs (core@shell structure NaYF4:Yb3+/Tm3+@NaYF4) embedded in micelles delivered NIR-to-NIR visualization, photothermal therapy, and high drug capacity. Further surface modification of micelles with a thermosensitive polymer (poly-N-vinylcaprolactam) exhibiting a conformation transition provided gradual drug (doxorubicin) release. In addition, the decoration of UCNP micelles with Ag nanoparticles (Ag NPs) synthesized in situ by silver ion reduction enhanced the cytotoxicity of micelles at cell growth temperature. Cell viability assessment on Sk-Br-3, MDA-MB-231, and WI-26 cell lines confirmed this effect. The efficiency of the prepared UCNP complex was evaluated in vivo by Sk-Br-3 xenograft regression in mice for 25 days after peritumoral injection and photoactivation of the lesions with NIR light. The designed polymer micelles hold promise as a photoactivated theranostic agent with quattro-functionalities (NIR absorption, photothermal effect, Ag NP cytotoxicity, and Dox loading) that provides imaging along with chemo- and photothermal therapy enhanced with Ag NPs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Animais , Camundongos , Micelas , Terapia Fototérmica , Prata , Nanopartículas/química , Polímeros/química , Doxorrubicina/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
4.
Anal Chem ; 94(12): 4901-4905, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35285614

RESUMO

The biodistribution of chemotherapy compounds within tumor tissue is one of the main challenges in the development of antineoplastic drugs, and techniques for simple, inexpensive, sensitive, and selective detection of various analytes in tumors are of great importance. In this paper we propose the use of platinized carbon nanoelectrodes (PtNEs) for the electrochemical detection of platinum-based drugs in various biological models, including single cells and tumor spheroids in vitro and inside solid tumors in vivo. We have demonstrated the quantitative direct detection of Pt(II) in breast adenocarcinoma MCF-7 cells treated with cisplatin and a cisplatin-based DNP prodrug. To realize the potential of this technique in advanced tumor models, we measured Pt(II) in 3D tumor spheroids in vitro and in tumor-bearing mice in vivo. The concentration gradient of Pt(II) species correlated with the distance from the sample surface in MCF-7 tumor spheroids. We then performed the detection of Pt(II) species in tumor-bearing mice treated intravenously with cisplatin and DNP. We found that there was deeper penetration of DNP in comparison to cisplatin. This research demonstrates a minimally invasive, real-time electrochemical technique for the study of platinum-based drugs.


Assuntos
Antineoplásicos , Pró-Fármacos , Animais , Cisplatino/química , Cisplatino/farmacologia , Humanos , Células MCF-7 , Camundongos , Pró-Fármacos/química , Distribuição Tecidual
5.
Inorg Chem ; 61(37): 14705-14717, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36047922

RESUMO

We report herein a Pt(IV) prodrug with metronidazole in axial positions Pt-Mnz. The nitroaromatic axial ligand was conjugated with a cisplatin scaffold to irreversibly reduce under hypoxic conditions, thereby retaining the Pt(IV) prodrug in the area of hypoxia. X-ray near-edge adsorption spectroscopy (XANES) on dried drug-preincubated tumor cell samples revealed a gradual release of cisplatin from the Pt-Mnz prodrug instead of rapid intracellular degradation. The ability of the prodrug to penetrate into three-dimensional (3D) spheroid cellular cultures was evaluated by a novel electrochemical assay via a platinum-coated carbon nanoelectrode, capable of single-cell measurements. Using a unique technique of electrochemical measurements in single tumor spheroids, we were able to both detect the real-time response of the axial ligand to hypoxia and establish the depth of penetration of the drug into the tumor model.


Assuntos
Antineoplásicos , Pró-Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbono , Linhagem Celular Tumoral , Cisplatino/química , Humanos , Hipóxia , Ligantes , Metronidazol/farmacologia , Platina/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia
6.
Molecules ; 27(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35566114

RESUMO

Upconverting nanoparticles have unique spectral and photophysical properties that make them suitable for development of theranostics for imaging and treating large and deep-seated tumors. Nanoparticles based on NaYF4 crystals doped with lanthanides Yb3+ and Er3+ were obtained by the high-temperature decomposition of trifluoroacetates in oleic acid and 1-octadecene. Such particles have pronounced hydrophobic properties. Therefore, to obtain stable dispersions in aqueous media for the study of their properties in vivo and in vitro, the polyethylene glycol (PEG)-glycerolipids of various structures were obtained. To increase the circulation time of PEG-lipid coated nanoparticles in the bloodstream, long-chain substituents are needed to be attached to the glycerol backbone using ether bonds. To prevent nanoparticle aggregation, an L-cysteine-derived negatively charged carboxy group should be included in the lipid molecule.


Assuntos
Nanopartículas , Polietilenoglicóis , Cisteína , Fluoretos/química , Nanopartículas/química , Ácido Oleico , Polietilenoglicóis/química , Ítrio/química
7.
Molecules ; 27(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36235084

RESUMO

Modern biocompatible materials of both natural and synthetic origin, in combination with advanced techniques for their processing and functionalization, provide the basis for tissue engineering constructs (TECs) for the effective replacement of specific body defects and guided tissue regeneration. Here we describe TECs fabricated using electrospinning and 3D printing techniques on a base of synthetic (polylactic-co-glycolic acids, PLGA) and natural (collagen, COL, and hyaluronic acid, HA) polymers impregnated with core/shell ß-NaYF4:Yb3+,Er3+/NaYF4 upconversion nanoparticles (UCNPs) for in vitro control of the tissue/scaffold interaction. Polymeric structures impregnated with core/shell ß-NaYF4:Yb3+,Er3+/NaYF4 nanoparticles were visualized with high optical contrast using laser irradiation at 976 nm. We found that the photoluminescence spectra of impregnated scaffolds differ from the spectrum of free UCNPs that could be used to control the scaffold microenvironment, polymer biodegradation, and cargo release. We proved the absence of UCNP-impregnated scaffold cytotoxicity and demonstrated their high efficiency for cell attachment, proliferation, and colonization. We also modified the COL-based scaffold fabrication technology to increase their tensile strength and structural stability within the living body. The proposed approach is a technological platform for "smart scaffold" development and fabrication based on bioresorbable polymer structures impregnated with UCNPs, providing the desired photoluminescent, biochemical, and mechanical properties for intravital visualization and monitoring of their behavior and tissue/scaffold interaction in real time.


Assuntos
Nanopartículas , Engenharia Tecidual , Materiais Biocompatíveis/farmacologia , Colágeno/química , Ácido Hialurônico , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Alicerces Teciduais/química
8.
Bioconjug Chem ; 32(4): 763-781, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33691403

RESUMO

Herein, we describe the design, synthesis, and biological evaluation of novel betulin and N-acetyl-d-galactosamine (GalNAc) glycoconjugates and suggest them as targeted agents against hepatocellular carcinoma. We prepared six conjugates derived via the C-3 and C-28 positions of betulin with one or two saccharide ligands. These molecules demonstrate high affinity to the asialoglycoprotein receptor (ASGPR) of hepatocytes assessed by in silico modeling and surface plasmon resonance tests. Cytotoxicity studies in vitro revealed a bivalent conjugate with moderate activity, selectivity of action, and cytostatic properties against hepatocellular carcinoma cells HepG2. An additional investigation confirmed the specific engagement with HepG2 cells by the enhanced generation of reactive oxygen species. Stability tests demonstrated its lability to acidic media and to intracellular enzymes. Therefore, the selected bivalent conjugate represents a new potential agent targeted against hepatocellular carcinoma. Further extensive studies of the cellular uptake in vitro and the real-time microdistribution in the murine liver in vivo for fluorescent dye-labeled analogue showed its selective internalization into hepatocytes due to the presence of GalNAc ligand in comparison with reference compounds. The betulin and GalNAc glycoconjugates can therefore be considered as a new strategy for developing therapeutic agents based on natural triterpenoids.


Assuntos
Acetilgalactosamina/química , Antineoplásicos/farmacologia , Receptor de Asialoglicoproteína/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Triterpenos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Corantes Fluorescentes/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Ressonância de Plasmônio de Superfície
9.
Anal Chem ; 92(12): 8010-8014, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32441506

RESUMO

In vivo monitoring of reactive oxygen species (ROS) in tumors during treatment with anticancer therapy is important for understanding the mechanism of action and in the design of new anticancer drugs. In this work, a platinized nanoelectrode is placed into a single cell for detection of the ROS signal, and drug-induced ROS production is then recorded. The main advantages of this method are the short incubation time with the drug and its high sensitivity which allows the detection of low intracellular ROS concentrations. We have shown that our new method can measure the ROS response to chemotherapy in tumor-bearing mice in real-time. ROS levels were measured in vivo inside the tumor at different depths in response to doxorubicin. This work provides an effective new approach for the measurement of intracellular ROS by platinized nanoelectrodes.


Assuntos
Antineoplásicos/farmacologia , Técnicas Biossensoriais , Doxorrubicina/farmacologia , Técnicas Eletroquímicas , Espécies Reativas de Oxigênio/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias Experimentais/diagnóstico , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Células PC-3 , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
10.
Biochim Biophys Acta Gen Subj ; 1868(5): 130582, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38340879

RESUMO

BACKGROUND: Riboflavin (vitamin B2) is one of the most important water-soluble vitamins and a coenzyme involved in many biochemical processes. It has previously been shown that adjuvant therapy with flavin mononucleotide (a water-soluble form of riboflavin) correlates with normalization of clinically relevant immune markers in patients with COVID-19, but the mechanism of this effect remains unclear. Here, the antiviral and anti-inflammatory effects of riboflavin were investigated to elucidate the molecular mechanisms underlying the riboflavin-induced effects. METHODS: Riboflavin was evaluated for recombinant SARS-CoV-2 PLpro inhibition in an enzyme kinetic assay and for direct inhibition of SARS-CoV-2 replication in Vero E6 cells, as well as for anti-inflammatory activity in polysaccharide-induced inflammation models, including endothelial cells in vitro and acute lung inflammation in vivo. RESULTS: For the first time, the ability of riboflavin at high concentrations (above 50 µM) to inhibit SARS-CoV-2 PLpro protease in vitro was demonstrated; however, no inhibition of viral replication in Vero E6 cells in vitro was found. At the same time, riboflavin exerted a pronounced anti-inflammatory effect in the polysaccharide-induced inflammation model, both in vitro, preventing polysaccharide-induced cell death, and in vivo, reducing inflammatory markers (IL-1ß, IL-6, and TNF-α) and normalizing lung histology. CONCLUSIONS: It is concluded that riboflavin reveals anti-inflammatory rather than antiviral activity for SARS-CoV-2 infection. GENERAL SIGNIFICANCE: Riboflavin could be suggested as a promising compound for the therapy of inflammatory diseases of broad origin.


Assuntos
COVID-19 , Células Endoteliais , Humanos , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Antivirais/farmacologia , Riboflavina/farmacologia , Polissacarídeos , Água
11.
ACS Appl Mater Interfaces ; 15(10): 12882-12894, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854172

RESUMO

Controlled photoreduction of Pt(IV) prodrugs is a challenging task due to the possibility of targeted light-controlled activation of anticancer agents without affecting healthy tissues. Also, a conjugation of photosensitizers and clinically used platinum drugs into one Pt(IV) prodrug allows combining photodynamic therapy and chemotherapy approaches into one molecule. Herein, we designed the cisplatin-based Pt(IV) prodrug Riboplatin with tetraacetylriboflavin in the axial position. A novel Pt(IV) prodrug is able to act both as a photodynamic therapy (PDT) agent through the conversion of ground-state 3O2 to excited-state 1O2 and as an agent of photoactivated chemotherapy (PACT) through releasing of cisplatin under gentle blue light irradiation, without the requirement of a reducing agent. The light-induced behavior of Riboplatin was investigated using an electrochemical sensor in MCF-7 tumor spheroids. Photocontrolled cisplatin release and ROS generation were detected electrochemically in real time. This appears to be the first confirmation of simultaneous photoactivated release of anticancer drug cisplatin and ROS from a dual-action Pt(IV) prodrug observed from the inside of living tumor spheroids.


Assuntos
Antineoplásicos , Pró-Fármacos , Cisplatino/farmacologia , Cisplatino/química , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Espécies Reativas de Oxigênio , Antineoplásicos/farmacologia , Antineoplásicos/química , Platina/química , Linhagem Celular Tumoral
12.
Int J Biol Macromol ; 215: 501-511, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35716792

RESUMO

Wide application of chitosan in modern technologies is limited by the lack of reliable and low-cost techniques to prepare size-tuned constructs with a complex surface morphology, improved optical and mechanical properties. We report a new simple method for preparation of transparent thermoreversible chitosan alcogels from chitosan/H2O/ethanol ternary systems. This method, termed "low temperature thermally induced phase separation under non-freezing conditions" (LT-TIPS-NF), fine tunes gelation by adjusting only temperature (from 5 to -25 °C) and varying the initial content of chitosan (from 0.5 to 2.0 wt%) and ethanol (from 28.5 to 47.5 vol%). Transparent non-swelling final constructs of complex shape are prepared by fixing the pre-formed alcogels with a base solution. The size of the gel constructs is limited only by the dimensions of the mold and the cooling chamber. The LT-TIPS-NF is applicable both in injection molding and 3D printing techniques. The in vitro and in vivo experiments show the absence of prominent cytotoxicity and well-defined cell adhesion on the obtained hydrogels. Thus, this facile and scalable technique provides the multifunctional chitosan gel preparation with easily controlled properties exploiting inexpensive, renewable, and environmentally friendly source polysaccharide. These materials have prospects for a variety of uses, especially for biomedical applications.


Assuntos
Quitosana , Etanol , Géis , Hidrogéis , Temperatura , Água
13.
J Med Chem ; 65(12): 8227-8244, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35675651

RESUMO

We report herein the design, synthesis, and biological investigation of a series of novel Pt(IV) prodrugs with non-steroidal anti-inflammatory drugs naproxen, diclofenac, and flurbiprofen, as well as these with stearic acid in the axial position. Six Pt(IV) prodrugs 5-10 were designed, which showed superior antiproliferative activity compared to cisplatin as well as an ability to overcome tumor cell line resistance to cisplatin. By tuning the drug lipophilicity via variation of the axial ligands, the most potent Pt(IV) prodrug 7 was obtained, with an enhanced cellular accumulation of up to 153-fold that of cisplatin and nanomolar cytotoxicity both in 2D and 3D cell cultures. Pt2+ species were detected at different depths of MCF-7 spheroids after incubation with Pt(IV) prodrugs using a Pt-coated carbon nanoelectrode. Cisplatin accumulation in vivo in the murine mammary EMT6 tumor tissue of BALB/c mice after Pt(IV) prodrug injection was proved electrochemically as well. The drug tolerance study on BALB/c mice showed good tolerance of 7 in doses up to 8 mg/kg.


Assuntos
Anti-Inflamatórios não Esteroides , Antineoplásicos , Compostos de Platina , Pró-Fármacos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Desenho de Fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Compostos de Platina/farmacologia , Pró-Fármacos/farmacologia
14.
Front Bioeng Biotechnol ; 9: 783834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926429

RESUMO

Bioprinting emerges as a powerful flexible approach for tissue engineering with prospective capability to produce tissue on demand, including biomimetic hollow-core fiber structures. In spite of significance for tissue engineering, hollow-core structures proved difficult to fabricate, with the existing methods limited to multistage, time-consuming, and cumbersome procedures. Here, we report a versatile cell-friendly photopolymerization approach that enables single-step prototyping of hollow-core as well as solid-core hydrogel fibers initially loaded with living cells. This approach was implemented by extruding cell-laden hyaluronic acid glycidyl methacrylate hydrogel directly into aqueous solution containing free radicals generated by continuous blue light photoexcitation of the flavin mononucleotide/triethanolamine photoinitiator. Diffusion of free radicals from the solution to the extruded structure initiated cross-linking of the hydrogel, progressing from the structure surface inwards. Thus, the cross-linked wall is formed and its thickness is limited by penetration of free radicals in the hydrogel volume. After developing in water, the hollow-core fiber is formed with centimeter range of lengths. Amazingly, HaCaT cells embedded in the hydrogel successfully go through the fabrication procedure. The broad size ranges have been demonstrated: from solid core to 6% wall thickness of the outer diameter, which was variable from sub-millimeter to 6 mm, and Young's modulus ∼1.6 ± 0.4 MPa. This new proof-of-concept fibers photofabrication approach opens lucrative opportunities for facile three-dimensional fabrication of hollow-core biostructures with controllable geometry.

15.
Nanomaterials (Basel) ; 11(9)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34578550

RESUMO

Formulation of promising anticancer herbal drug curcumin as a nanoscale-sized curcumin (nanocurcumin) improved its delivery to cells and organisms both in vitro and in vivo. We report on coupling nanocurcumin with upconversion nanoparticles (UCNPs) using Poly (lactic-co-glycolic Acid) (PLGA) to endow visualisation in the near-infrared transparency window. Nanocurcumin was prepared by solvent-antisolvent method. NaYF4:Yb,Er (UCNP1) and NaYF4:Yb,Tm (UCNP2) nanoparticles were synthesised by reverse microemulsion method and then functionalized it with PLGA to form UCNP-PLGA nanocarrier followed up by loading with the solvent-antisolvent process synthesized herbal nanocurcumin. The UCNP samples were extensively characterised with XRD, Raman, FTIR, DSC, TGA, UV-VIS-NIR spectrophotometer, Upconversion spectrofluorometer, HRSEM, EDAX and Zeta Potential analyses. UCNP1-PLGA-nanocurcumin exhibited emission at 520, 540, 660 nm and UCNP2-PLGA-nanocurmin showed emission at 480 and 800 nm spectral bands. UCNP-PLGA-nanocurcumin incubated with rat glioblastoma cells demonstrated moderate cytotoxicity, 60-80% cell viability at 0.12-0.02 mg/mL marginally suitable for therapeutic applications. The cytotoxicity of UCNPs evaluated in tumour spheroids models confirmed UCNP-PLGA-nanocurcumin therapeutic potential. As-synthesised curcumin-loaded nanocomplexes were administered in tumour-bearing laboratory animals (Lewis lung cancer model) and showed adequate contrast to enable in vivo and ex vivo study of UCNP-PLGA-nanocurcumin bio distribution in organs, with dominant distribution in the liver and lungs. Our studies demonstrate promise of nanocurcumin-loaded upconversion nanoparticles for theranostics applications.

16.
Biomater Sci ; 8(16): 4570-4580, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32780056

RESUMO

Lanthanide-doped upconversion nanoparticles (UCNPs) are promising bioimaging agents that emit light under near infra-red excitation, capable of penetrating deep in biotissues with a high signal-to-noise ratio. Their successful implementation is principally associated with surface functionalization. Here, we report on UCNP surface modification with highly hydrophilic, endogenous, non-toxic, non-immunogenic colominic acid, conferring "stealth" properties. We proposed surface functionalization of UCNPs based on a two-step strategy, which consists of hydrophilization with polyethyleneimine and attachment of colominic acid by electrostatic or covalent bond formation. Analysis revealed that regardless of the nature of the bond, colominic acid acted as a non-cytotoxic UCNP surface coating with low nonspecific blood protein adsorption. UCNP-colominic acid nanocomplexes exhibited low uptake by macrophages in vitro, which plays an active role in inflammatory reactions. We demonstrated the superiority of colominic acid compared to polyethylene glycol coating in terms of the prolonged circulation time in the bloodstream of small animals when injected intravenously. The colominic acid coating made it possible to prolong the UCNP circulation time up to 3 h. This led to the efficient UCNP accumulation in the inflammation site due to microvascular remodeling, accompanied by an enhanced uptake and retention effect. UCNP-assisted imaging of inflammation in the whole-body mode as well as local visualization of blood vessels were acquired in vivo. These collective findings validate the functional significance of UCNP decoration with colominic acid for their application in bioimaging.


Assuntos
Nanopartículas , Animais , Polietilenoglicóis , Polietilenoimina , Polissacarídeos
17.
Front Chem ; 8: 295, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32457866

RESUMO

Local overheating of biotissue is a critical step for biomedical applications, such as photothermal therapy, enhancement of vascular permeability, remote control of drug release, and so on. Overheating of biological tissue when exposed to light is usually realized by utilizing the materials with a high-absorption cross section (gold, silica, carbon nanoparticles, etc.). Here, we demonstrate core/shell NaYF4:Yb3+, Tm3+/NaYF4 upconversion nanoparticles (UCNPs) commonly used for bioimaging as promising near-infrared (NIR) absorbers for local overheating of biotissue. We assume that achievable temperature of tissue labeled with nanoparticles is high enough because of Yb3+ resonance absorption of NIR radiation, whereas the use of auxiliary light-absorbing materials or shells is optional for photothermal therapy. For this purpose, a computational model of tissue heating based on the energy balance equations was developed and verified with the experimentally obtained thermal-graphic maps of a mouse in response to the 975-nm laser irradiation. Labeling of biotissue with UCNPs was found to increase the local temperature up to 2°C compared to that of the non-labeled area under the laser intensity lower than 1 W/cm2. The cellular response to the UCNP-initiated hyperthermia at subcritical ablation temperatures (lower than 42°C) was demonstrated by measuring the heat shock protein overexpression. This indicates that the absorption cross section of Yb3+ in UCNPs is relatively large, and microscopic temperature of nanoparticles exceeds the integral tissue temperature. In summary, a new approach based on the use of UCNP without any additional NIR absorbers was used to demonstrate a simple approach in the development of photoluminescent probes for simultaneous bioimaging and local hyperthermia.

18.
J Med Chem ; 63(21): 13031-13063, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32985193

RESUMO

A series of 73 ligands and 73 of their Cu+2 and Cu+1 copper complexes with different geometries, oxidation states of the metal, and redox activities were synthesized and characterized. The aim of the study was to establish the structure-activity relationship within a series of analogues with different substituents at the N(3) position, which govern the redox potentials of the Cu+2/Cu+1 redox couples, ROS generation ability, and intracellular accumulation. Possible cytotoxicity mechanisms, such as DNA damage, DNA intercalation, telomerase inhibition, and apoptosis induction, have been investigated. ROS formation in MCF-7 cells and three-dimensional (3D) spheroids was proven using the Pt-nanoelectrode. Drug accumulation and ROS formation at 40-60 µm spheroid depths were found to be the key factors for the drug efficacy in the 3D tumor model, governed by the Cu+2/Cu+1 redox potential. A nontoxic in vivo single-dose evaluation for two binuclear mixed-valence Cu+1/Cu+2 redox-active coordination compounds, 72k and 61k, was conducted.


Assuntos
Complexos de Coordenação/química , Cobre/química , Imidazóis/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , Dano ao DNA/efeitos dos fármacos , Humanos , Ligantes , Células MCF-7 , Modelos Biológicos , Conformação Molecular , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Esferoides Celulares/efeitos dos fármacos , Relação Estrutura-Atividade , Telomerase/antagonistas & inibidores , Telomerase/metabolismo
19.
Mater Sci Eng C Mater Biol Appl ; 75: 1075-1082, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28415392

RESUMO

Poly(vinyl alcohol) (PVA) hydrogels are widely employed for various biomedical applications, including tissue engineering, due to their biocompatibility, high water solubility, low protein adsorption, and chemical stability. However, non-charged surface of PVA-based hydrogels is not optimal for cell adhesion and spreading. Here, cross-linked macroporous hydrogels based on low molecular weight acrylated PVA (Acr-PVA) was synthesized by modification of the pendant alcohol groups on the PVA with glycidyl methacrylate (GMA). To enhance cell affinity, charged groups were introduced to the hydrogel composition. For this purpose, Acr-PVA was copolymerized with either negatively charged acrylic acid (AA) or positively charged 2-(diethylamino) ethyl methacrylate (DEAEMA) monomers. A surface charge of the obtained hydrogels was found to be in function of the co-monomer type and content. Confocal microscopy observations confirmed that adhesion and spreading of both mouse fibroblasts (L929) and human mesenchymal stem cells (hMSC) on the modified Acr-PVA-AA and Acr-PVA-DEAEMA hydrogels were better than those on the non-modified Acr-PVA hydrogel. The increase of DEAEMA monomer content from 5 to 15mol% resulted in the enhancement of cell viability which was 1.5-fold higher for Acr-PVA-DEAEMA-15 hydrogel than that of the non-modified Acr-PVA hydrogel sample.


Assuntos
Fibroblastos/metabolismo , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Álcool de Polivinil/química , Engenharia Tecidual , Animais , Adesão Celular , Linhagem Celular , Compostos de Epóxi/química , Fibroblastos/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Metacrilatos/química , Camundongos , Porosidade
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