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1.
Pharmaceutics ; 15(6)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37376150

RESUMO

Glioblastoma (GBM) is the most common primary brain cancer in adults. Despite the remarkable advancements in recent years in the realm of cancer diagnosis and therapy, regrettably, GBM remains the most lethal form of brain cancer. In this view, the fascinating area of nanotechnology has emerged as an innovative strategy for developing novel nanomaterials for cancer nanomedicine, such as artificial enzymes, termed nanozymes, with intrinsic enzyme-like activities. Therefore, this study reports for the first time the design, synthesis, and extensive characterization of innovative colloidal nanostructures made of cobalt-doped iron oxide nanoparticles chemically stabilized by a carboxymethylcellulose capping ligand (i.e., Co-MION), creating a peroxidase-like (POD) nanozyme for biocatalytically killing GBM cancer cells. These nanoconjugates were produced using a strictly green aqueous process under mild conditions to create non-toxic bioengineered nanotherapeutics against GBM cells. The nanozyme (Co-MION) showed a magnetite inorganic crystalline core with a uniform spherical morphology (diameter, 2R = 6-7 nm) stabilized by the CMC biopolymer, producing a hydrodynamic diameter (HD) of 41-52 nm and a negatively charged surface (ZP~-50 mV). Thus, we created supramolecular water-dispersible colloidal nanostructures composed of an inorganic core (Cox-MION) and a surrounding biopolymer shell (CMC). The nanozymes confirmed the cytotoxicity evaluated by an MTT bioassay using a 2D culture in vitro of U87 brain cancer cells, which was concentration-dependent and boosted by increasing the cobalt-doping content in the nanosystems. Additionally, the results confirmed that the lethality of U87 brain cancer cells was predominantly caused by the production of toxic cell-damaging reactive oxygen species (ROS) through the in situ generation of hydroxyl radicals (·OH) by the peroxidase-like activity displayed by nanozymes. Thus, the nanozymes induced apoptosis (i.e., programmed cell death) and ferroptosis (i.e., lipid peroxidation) pathways by intracellular biocatalytic enzyme-like activity. More importantly, based on the 3D spheroids model, these nanozymes inhibited tumor growth and remarkably reduced the malignant tumor volume after the nanotherapeutic treatment (ΔV~40%). The kinetics of the anticancer activity of these novel nanotherapeutic agents decreased with the time of incubation of the GBM 3D models, indicating a similar trend commonly observed in tumor microenvironments (TMEs). Furthermore, the results demonstrated that the 2D in vitro model overestimated the relative efficiency of the anticancer agents (i.e., nanozymes and the DOX drug) compared to the 3D spheroid models. These findings are notable as they evidenced that the 3D spheroid model resembles more precisely the TME of "real" brain cancer tumors in patients than 2D cell cultures. Thus, based on our groundwork, 3D tumor spheroid models might be able to offer transitional systems between conventional 2D cell cultures and complex biological in vivo models for evaluating anticancer agents more precisely. These nanotherapeutics offer a wide avenue of opportunities to develop innovative nanomedicines for fighting against cancerous tumors and reducing the frequency of severe side effects in conventionally applied chemotherapy-based treatments.

2.
Int J Biol Macromol ; 231: 123363, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36690232

RESUMO

The contamination and pollution of wastewater with a wide diversity of chemical, microbiological, and hazardous substances is a field of raising environmental concern. In this study, we developed, for the first time, new hybrid multifunctional nanoplexes composed of ZnS semiconductor quantum dots (ZnS QDs) chemically biofunctionalized with epsilon-poly-l-lysine (ɛPL) and coupled with magnetic iron oxide nanoparticles (MION, Fe3O4) stabilized by carboxymethylcellulose (CMC) for the photodegradation (ZnS) of organic molecules and antibacterial activity (ɛPL) with a potential of recovery by an external magnetic field (Fe3O4). These nanosystems, which were synthesized entirely through a green aqueous process, were comprehensively characterized regarding their physicochemical properties combined with spectroscopic and morphological features. The results demonstrated that supramolecular colloidal nanoplexes were formed owing to the strong cationic/anionic electrostatic interactions between the biomacromolecule capping ligands of the two nanoconjugates (i.e., polypeptide in ZnS@ɛPL and polysaccharide in Fe3O4@CMC). Moreover, these nanosystems showed photocatalytic degradation of methylene blue (MB) used as a model dye pollutant in water. Besides MB, methyl orange, congo red, and rhodamine dyes were also tested for selectivity investigation of the photodegradation by the nanoplexes. The antibacterial activity ascribed to the ɛPL biomolecule was confirmed against Gram-positive and Gram-negative bacteria, including drug-resistance field strains. Hence, it is envisioned that these novel green nanoplexes offer a new avenue of alternatives to be employed for reducing organic pollutants and inactivating pathogenic bacteria in water and wastewater treatment, benefiting from easy magnetic recovery.


Assuntos
Poluentes Ambientais , Pontos Quânticos , Purificação da Água , Pontos Quânticos/química , Corantes/química , Carboximetilcelulose Sódica/química , Polilisina , Antibacterianos , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Nanopartículas Magnéticas de Óxido de Ferro , Água
3.
Polymers (Basel) ; 15(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38231902

RESUMO

Diabetic foot ulcers (DFUs) are considered one of the most severe chronic complications of diabetes and can lead to amputation in severe cases. In addition, bacterial infections in diabetic chronic wounds aggravate this scenario by threatening human health. Wound dressings made of polymer matrices with embedded metal nanoparticles can inhibit microorganism growth and promote wound healing, although the current clinical treatments for diabetic chronic wounds remain unsatisfactory. In this view, this research reports the synthesis and characterization of innovative hybrid hydrogels made of carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) chemically crosslinked by citric acid (CA) functionalized with silver nanoparticles (AgNPs) generated in situ using an eco-friendly aqueous process. The results assessed through comprehensive in vitro and in vivo assays demonstrated that these hybrid polymer hydrogels functionalized with AgNPs possess physicochemical properties, cytocompatibility, hemocompatibility, bioadhesion, antibacterial activity, and biocompatibility suitable for wound dressings to support chronic wound healing process as well as preventing and treating bacterial infections. Hence, it can be envisioned that, with further research and development, these polymer-based hybrid nanoplatforms hold great potential as an important tool for creating a new generation of smart dressings for treating chronic diabetic wounds and opportunistic bacterial infections.

4.
Pharmaceutics ; 14(10)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36297660

RESUMO

Glioblastoma remains the most lethal form of brain cancer, where hybrid nanomaterials biofunctionalized with polysaccharide peptides offer disruptive strategies relying on passive/active targeting and multimodal therapy for killing cancer cells. Thus, in this research, we report for the first time the rational design and synthesis of novel hybrid colloidal nanostructures composed of gold nanoparticles stabilized by trisodium citrate (AuNP@TSC) as the oxidase-like nanozyme, coupled with cobalt-doped superparamagnetic iron oxide nanoparticles stabilized by carboxymethylcellulose ligands (Co-MION@CMC) as the peroxidase-like nanozyme. They formed inorganic-inorganic dual-nanozyme systems functionalized by a carboxymethylcellulose biopolymer organic shell, which can trigger a biocatalytic cascade reaction in the cancer tumor microenvironment for the combination of magnetothermal-chemodynamic therapy. These nanoassemblies were produced through a green aqueous process under mild conditions and chemically biofunctionalized with integrin-targeting peptide (iRDG), creating bioengineered nanocarriers. The results demonstrated that the oxidase-like nanozyme (AuNP) was produced with a crystalline face-centered cubic nanostructure, spherical morphology (diameter = 16 ± 3 nm), zeta potential (ZP) of -50 ± 5 mV, and hydrodynamic diameter (DH) of 15 ± 1 nm. The peroxide-like nanostructure (POD, Co-MION@CMC) contained an inorganic crystalline core of magnetite and had a uniform spherical shape (2R = 7 ± 1 nm) which, summed to the contribution of the CMC shell, rendered a hydrodynamic diameter of 45 ± 4 nm and a negative surface charge (ZP = -41 ± 5 mV). Upon coupling both nanozymes, water-dispersible colloidal supramolecular vesicle-like organic-inorganic nanostructures were produced (AuNP//Co-MION@CMC, ZP = -45 ± 4 mV and DH = 28 ± 3 nm). They confirmed dual-nanozyme cascade biocatalytic activity targeted by polymer-peptide conjugates (AuNP//Co-MION@CMC_iRGD, ZP = -29 ± 3 mV and DH = 60 ± 4 nm) to kill brain cancer cells (i.e., bioenergy "starvation" by glucose deprivation and oxidative stress through reactive oxygen species generation), which was boosted by the magneto-hyperthermotherapy effect when submitted to the alternating magnetic field (i.e., induced local thermal stress by "nanoheaters"). This groundwork offers a wide avenue of opportunities to develop innovative theranostic nanoplatforms with multiple integrated functionalities for fighting cancer and reducing the harsh side effects of conventional chemotherapy.

5.
Int J Biol Macromol ; 210: 530-544, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35513094

RESUMO

Among the most lethal forms of cancer, malignant brain tumors persist as one of the greatest challenges faced by oncologists, where nanotechnology-driven theranostics can play a critical role in developing novel polymer-based supramolecular nanoarchitectures with multifunctional and multi-modal characteristics to fight cancer. However, it is virtually a consensus that, besides the complexity of active delivering anticancer drugs by the nanocarriers to the tumor site, the current evaluation methods primarily relying on in vitro assays and in vivo animal models have been accounted for the low translational effectiveness to clinical applications. In this view, the chick chorioallantoic membrane (CAM) assay has been increasingly recognized as one of the best preclinical models to study the effects of anticancer drugs on the tumor microenvironment (TME). Thus, in this study, we designed, characterized, and developed novel hybrid nanostructures encompassing chemically functionalized carboxymethylcellulose (CMC) with mitochondria-targeting pro-apoptotic peptide (KLA) and cell-penetrating moiety (cysteine, CYS) with fluorescent inorganic semiconductor (Ag-In-S, AIS) for simultaneously bioimaging and inducing glioblastoma cancer cell (U-87 MG, GBM) death. The results demonstrated that the CMC-peptide macromolecules produced supramolecular vesicle-like nanostructures with aqueous colloidal stability suitable as nanocarriers for passive and active targeting of cancer tumors. The optical properties and physicochemical features of the nanoconjugates confirmed their suitability as photoluminescent nanoprobes for cell bioimaging and intracellular tracking. Moreover, the results in vitro demonstrated a notable killing activity towards GBM cells of cysteine-bearing CMC conjugates coupled with pro-apoptotic KLA peptides. More importantly, compared to doxorubicin (DOX), a model anticancer drug in chemotherapy that is highly toxic, these innovative nanohybrids nanoconjugates displayed higher lethality against U-87 MG cancer cells. In vivo CAM assays validated these findings where the nanohybrids demonstrated a significant reduction of GBM tumor progression (41% area) and evidenced an antiangiogenic activity. These results pave the way for developing polymer-based hybrid nanoarchitectonics applied as targeted multifunctional theranostics for simultaneous imaging and therapy against glioblastoma while possibly reducing the systemic toxicity and side-effects of conventional anticancer chemotherapeutic agents.


Assuntos
Antineoplásicos , Neoplasias Encefálicas , Glioblastoma , Pontos Quânticos , Animais , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Carboximetilcelulose Sódica/química , Linhagem Celular Tumoral , Cisteína , Doxorrubicina/química , Glioblastoma/tratamento farmacológico , Nanoconjugados/uso terapêutico , Polímeros/uso terapêutico , Pontos Quânticos/química , Nanomedicina Teranóstica , Microambiente Tumoral
6.
Int J Biol Macromol ; 182: 1091-1111, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33892028

RESUMO

Acute or chronic brain injuries promote deaths and the life-long debilitating neurological status where, despite advances in therapeutic strategies, clinical outcome hardly achieves total patient recovery. In recent decades, brain tissue engineering emerged as an encouraging area of research for helping in damaged central nervous system (CNS) recovery. Polysaccharides are abundant naturally occurring biomacromolecules with a great potential enhancement of advanced technologies in brain tissue repair and regeneration (BTRR). Besides carrying rich biological information, polysaccharides can interact and communicate with biomolecules, including glycosaminoglycans present in cell membranes and many signaling moieties, growth factors, chemokines, and axon guidance molecules. This review includes a comprehensive investigation of the current progress on designing and developing polysaccharide-based soft matter biomaterials for BTRR. Although few interesting reviews concerning BTRR have been reported, this is the first report specifically focusing on covering multiple polysaccharides and polysaccharide-based functionalized biomacromolecules in this emerging and intriguing field of multidisciplinary knowledge. This review aims to cover the state of art challenges and prospects of this fascinating field while presenting the richness of possibilities of using these natural biomacromolecules for advanced biomaterials in prospective neural tissue engineering applications.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Engenharia Biomédica/métodos , Humanos
7.
Nanotheranostics ; 5(2): 213-239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614399

RESUMO

Overview: Malignant brain tumors remain one of the greatest challenges faced by health professionals and scientists among the utmost lethal forms of cancer. Nanotheranostics can play a pivotal role in developing revolutionary nanoarchitectures with multifunctional and multimodal capabilities to fight cancer. Mitochondria are vital organelles to eukaryotic cells, which have been recognized as a significant target in cancer therapy where, by damaging the mitochondria, it will cause irreparable cell death or apoptosis. Methods: We designed and produced novel hybrid nanostructures comprising a fluorescent semiconductor core (AgInS2, AIS) and cysteine-modified carboxymethylcellulose (termed thiomer, CMC_Cys) conjugated with mitochondria-targeting peptides (KLA) forming a macromolecular shell for combining bioimaging and for inducing brain cancer cell (U-87 MG) death. Results: The optical and physicochemical properties of the nanoconjugates demonstrated suitability as photoluminescent nanostructures for cell bioimaging and intracellular tracking. Additionally, the results proved a remarkable killing activity towards glioblastoma cells of cysteine-bearing CMC conjugates coupled with KLA peptides through the half-maximal effective concentration values, approximately 70-fold higher compared to the conjugate analogs without Cys residues. Moreover, these thiomer-based pro-apoptotic drug nanoconjugates displayed higher lethality against U-87 MG cancer cells than doxorubicin, a model drug in chemotherapy, although extremely toxic. Remarkably, these peptidomimetic nanohybrids demonstrated a relative "protective effect" regarding healthy cells while maintaining high killing activity towards malignant brain cells. Conclusion: These findings pave the way for developing hybrid nanoarchitectures applied as targeted multifunctional platforms for simultaneous imaging and therapy against cancer while minimizing the high systemic toxicity and side-effects of conventional drugs in anticancer chemotherapy.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Corantes Fluorescentes/química , Mitocôndrias/efeitos dos fármacos , Nanotecnologia , Peptidomiméticos , Medicina de Precisão/métodos , Linhagem Celular Tumoral , Humanos
8.
Environ Technol ; 42(13): 2046-2066, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31743650

RESUMO

In this work, it was developed three-dimensional (3D) porous hydrogel sponges produced by the freeze-dried process using chitosan polymer functionalized by 11-mercaptoundecanoic acid (MUA). These chitosan-based sponges were used as cationic adsorbents for the removal of anionic methyl orange (MO) dye, simulating a model organic pollutant in aqueous medium. Moreover, these porous 3D constructs were also evaluated as 'antibiotic-free' antibacterial materials against gram-negative and gram-positive bacteria, Pseudomonas aeruginosa and Staphylococcus aureus, respectively, which were used as model pathogens possibly found in contaminated hospital discharges. These 3D hydrogels were comprehensively characterized through morphological methods such as scanning electron microscopy and X-ray micro-computed tomography techniques, combined with FTIR, Raman, and UV-visible spectroscopy analyses. Additionally, the surface area, the degree of swelling, and the adsorption profiles and kinetics of these scaffolds were systematically investigated. The chemically thiolated chitosan (CHI-MUA) hydrogels were successfully produced with a supramolecular polymeric network based on hydrogen bonds, disulfide bonds, and hydrophobic interactions that resulted in higher stability in aqueous medium than hydrogels of pristine chitosan. CHI-MUA exhibited sponge-like three-dimensional structures, with highly interconnected and hierarchical pore size distribution with high porosity and surface area. These architectural aspects of the 3D sponges favoured the high adsorption capacity for MO dye (∼388 mg.g-1) in water with removal efficiency greater than 90% for MO solutions (from 20 mg.L-1-1200 mg.L-1). The adsorption data followed a pseudo-second-order kinetic model and adsorption isotherm analysis and spectroscopy studies suggested a multilayer behaviour with coexistence of adsorbent-adsorbate and adsorbate-adsorbate interactions. Additionally, the in vitro evaluation of toxicity (MTT and LIVE-DEAD® assays) of 3D-sponges revealed a non-toxic response and preliminary suitability for bio-related applications. Importantly, the 3D-sponges composed of chitosan-thiolated derivative proved high antibacterial activity, specificity against P. aeruginosa (model hazardous pathogen), equivalent to conventional antibiotic drugs, while no lethality against S. aureus (reference commensal bacteria) was observed.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Antibacterianos/farmacologia , Concentração de Íons de Hidrogênio , Cinética , Staphylococcus aureus , Microtomografia por Raio-X
9.
Mater Lett ; 277: 128279, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32834256

RESUMO

The earliest possible diagnosis and understanding of the infection mechanisms play a crucial role in the outcome of fighting viral diseases. Thus, we designed and developed for the first time, novel bioconjugates made of Ag-In-S@ZnS (ZAIS) fluorescent quantum dots coupled with ZIKA virus via covalent amide bond with carboxymethylcellulose (CMC) biopolymer for labeling and bioimaging the virus-host cell interactions mechanisms through confocal laser scanning microscopy. This work offers relevant insights regarding the profile of the ZIKA virus-nanoparticle conjugates interactions with VERO cells, which can be applied as a nanoplatform to elucidate the infection mechanisms caused by this viral disease.

10.
J Mater Chem B ; 8(32): 7166-7188, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32614035

RESUMO

Despite the undeniable advances in recent decades, cancer remains one of the deadliest diseases of the current millennium, where the triple-negative breast cancer (TNBC) is very aggressive, extremely metastatic, and resistant to conventional chemotherapy. The nanotheranostic approach focusing on targeting membrane receptors often expressed at abnormal levels by cancer cells can be a strategic weapon for fighting malignant tumors. Herein, we introduced a novel "all-in-one nanosoldier" made of colloidal hybrid nanostructures, which were designed for simultaneously targeting, imaging, and killing TNBC cells. These nanohybrids comprised four distinct components: (a) superparamagnetic iron oxide nanoparticles, as bi-functional nanomaterials for inducing ferroptosis via inorganic nanozyme-mediated catalysis and magnetotherapy by hyperthermia treatment; (b) carboxymethyl cellulose biopolymer, as a water-soluble capping macromolecule; (c) folic acid, as the membranotopic vector for targeting folate receptors; (d) and doxorubicin (DOX) drug for chemotherapy. The results demonstrated that this novel strategy was highly effective for targeting and killing TNBC cells in vitro, expressing high levels of folate membrane-receptors. The results evidenced that three integrated mechanisms triggered the deaths of the cancer cells in vitro: (a) ferroptosis, by magnetite nanoparticles inducing a Fenton-like reaction; (b) magneto-hyperthermia effect by generating heat under an alternate magnetic field; and (c) chemotherapy, through the DOX intracellular release causing DNA dysfunction. This "all-in-one nanosoldier" strategy offers a vast realm of prospective alternatives for attacking cancer cells, combining multimodal therapy and the delivery of therapeutic agents to diseased sites and preserving healthy cells, which is one of the most critical clinical challenges faced in fighting drug-resistant breast cancers.


Assuntos
Antineoplásicos/química , Doxorrubicina/química , Corantes Fluorescentes/química , Nanopartículas de Magnetita/química , Nanocápsulas/química , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/terapia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Terapia Combinada , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Humanos , Hipertermia Induzida/efeitos adversos , Campos Magnéticos , Nanopartículas de Magnetita/uso terapêutico , Terapia de Alvo Molecular , Imagem Óptica , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica
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