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1.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39065720

RESUMO

The green synthesis of silver nanoparticles (AgNPs) can be developed using safe and environmentally friendly routes, can replace potentially toxic chemical methods, and can increase the scale of production. This study aimed to synthesize AgNPs from aqueous extracts of guarana (Paullinia cupana) leaves and flowers, collected in different seasons of the year, as a source of active biomolecules capable of reducing silver ions (Ag+) and promoting the stabilization of colloidal silver (Ag0). The plant aqueous extracts were characterized regarding their metabolic composition by liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS), phenolic compound content, and antioxidant potential against free radicals. The synthesized AgNPs were characterized by UV/Vis spectrophotometry, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and scanning electron microscopy coupled to energy-dispersive X-ray spectrometry (EDX). The results demonstrated that the chemical characterization indicated the presence of secondary metabolites of many classes of compounds in the studied aqueous extracts studied, but alkaloids and flavonoids were predominant, which are widely recognized for their antioxidant capabilities. It was possible to notice subtle changes in the properties of the nanostructures depending on parameters such as seasonality and the part of the plant used, with the AgNPs showing surface plasmon resonance bands between 410 and 420 nm using the leaf extract and between 440 and 460 nm when prepared using the flower extract. Overall, the average hydrodynamic diameters of the AgNPs were similar among the samples (61.98 to 101.6 nm). Polydispersity index remained in the range of 0.2 to 0.4, indicating that colloidal stability did not change with storage time. Zeta potential was above -30 mV after one month of analysis, which is adequate for biological applications. TEM images showed AgNPs with diameters between 40.72 to 48.85 nm and particles of different morphologies. EDX indicated silver content by weight between 24.06 and 28.81%. The synthesized AgNPs exhibited antimicrobial efficacy against various pathogenic microorganisms of clinical and environmental interest, with MIC values between 2.12 and 21.25 µg/mL, which is close to those described for MBC values. Therefore, our results revealed the potential use of a native species of plant from Brazilian biodiversity combined with nanotechnology to produce antimicrobial agents.

2.
J Biophotonics ; 14(6): e202000487, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33638279

RESUMO

This study evaluated the optical absorbance spectrum of human monocytes, neutrophils and lymphocytes polarized, or not, to the inflammatory or immunoregulatory phenotypes. Peripheral human blood leukocytes were isolated and polarized (10 ng/mL) with LPS or IL-4 + LPS for 2 hours. After polarization, cells were washed and incubated for an additional 24 hours (monocytes and lymphocytes) or 12 hours (neutrophils). Next, cells were collected to evaluate the optical absorbance spectrum. The three types of leukocytes exhibited absorbance in the region from 450 to 900 nm, with greater absorbance at wavelengths lower than 570 nm. Lymphocytes had a second region of greater absorbance between 770 and 900 nm. Inflammatory monocytes and lymphocytes showed increased absorbance of blue, green and yellow wavelengths (monocytes), as well as red and infrared wavelengths (monocytes and lymphocytes). Immunoregulatory polarization altered the absorbance of monocytes and lymphocytes very little. Neutrophils treated with LPS or LPS + IL-4 exhibited lower absorbance at wavelengths higher than 575 nm compared to untreated cells. The present findings showed that leukocytes exhibit greater absorbance in regions of the spectrum that have not been much used in photobiomodulation (PBM), and the polarization of these cells can affect their capacity to absorb light. Taken together, these results suggest new perspectives in the use of PBM in the clinical setting depending on the wavelengths and the stage of the inflammatory process.


Assuntos
Leucócitos , Monócitos , Humanos , Linfócitos , Neutrófilos , Fenótipo
3.
Lasers Med Sci ; 36(3): 681-690, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32813258

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common head and neck malignancy; it has been shown that cancer stem cells (CSC) are present in OSCC and associated with tumor growth, invasion, metastasis, and therapeutic resistance. Photobiomodulation (PBM) is an alternative tool for oncologic treatment adverse effects such as oral mucositis (OM); however, controversy exists regarding the undesirable effects of PBM on tumor or CSC. This study aimed to evaluate in vitro, the effects of PBM, with the same dosimetric parameters as those used in the clinic for OM prevention and treatment, on OSCC cellular viability, as well as PBM's effect on CSC properties and its phenotype. OSCC cell lines were submitted to single or daily PBM with 3 J/cm2 and 6 J/cm2 and then the cellular viability was evaluated by MTT, NRU (neutral red uptake), and CVS (crystal violet staining). The CSC populations were evaluated by clonogenic formation assay, flow cytometry, and RT-qPCR. The single PBM with the 3 J/cm2 group was associated with increased cellular viability. Daily PBM with 3 J/cm2 and 6 J/cm2 was associated with a significant decrease in cellular viability. Additionally, daily PBM was not able to promote CSC self-renewal or the CD44high/ESAlow and CD44high/ESAhigh cellular phenotypes. Moreover, a decrease in the number of spheres and in the expression of the CSC related gene BMI1 was observed after daily PBM with 6 J/cm2. Daily PBM with 3 J/cm2 and 6 J/cm2 showed an inhibitory effect on cellular viability and was not able to promote the CSC self-renewal or phenotype.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Terapia com Luz de Baixa Intensidade , Neoplasias Bucais/radioterapia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Ensaio de Unidades Formadoras de Colônias , Humanos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Neoplasias Bucais/patologia , Fenótipo
4.
J Photochem Photobiol B ; 204: 111808, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006892

RESUMO

Photodynamic therapy (PDT) is effective in the treatment of different types of cancer, such as basal cell carcinoma and other superficial cancers. However, improvements in photosensitizer delivery are still needed, and the use of PDT against more deeply located tumors has been the subject of many studies. Thus, the goal of this study was to evaluate the efficacy of a nanoemulsion containing aluminium-phthalocyanine (AlPc-NE) as a mediator of photodynamic therapy (PDT-AlPc-NE) against grafted 4T1 breast adenocarcinoma tumors in mice (BALB/c). Short after the appearance of the tumor, the animals were divided into groups (n = 5) as follows: untreated; only AlPc-NE and treated with PDT-AlPc-NE. The tumor volume was measured with a digital calliper at specific times. The presence of metastasis in the lungs was evaluated by microtomography and histopathological analyses. The results show that the application of PDT-AlPc-NE eradicated the transplanted tumors in all the treated animals, while the animals from control groups presented a robust increase in the tumor volume. Still more significantly, microtomography showed the animals submitted the PDT-AlPc-NE to be free of detectable metastasis in the lungs. The histological analysis of the lungs further confirmed the results verified by the microtomography. Therefore, this study suggests that PDT-AlPc-NE is effective in the elimination of experimentally grafted breast tumors in mice and also in preventing the formation of metastasis in the lungs.


Assuntos
Adenocarcinoma/tratamento farmacológico , Alumínio/química , Neoplasias da Mama/tratamento farmacológico , Indóis/química , Neoplasias Pulmonares/tratamento farmacológico , Nanoestruturas/química , Fármacos Fotossensibilizantes/uso terapêutico , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Isoindóis , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Transplante Homólogo , Microtomografia por Raio-X
5.
Lasers Med Sci ; 34(3): 629-636, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30232646

RESUMO

The treatment of squamous cell carcinoma (SCC) involves surgery, chemotherapy, and/or radiotherapy, which can cause mucositis (inflammation of the oral mucosa that causes considerable pain and can compromise the continuity of oncological treatment). Photobiomodulation (PBM) has been successfully used in the treatment of mucositis, but doubts arise regarding the use of laser for areas in which tumor cells may remain. In this study, the effect of PBM on the viability, mitochondrial activity, proliferation, apoptosis, and migration of cells derived from oral SCC was evaluated. SCC9 cells were irradiated with laser (660 and 780 nm, using 11 dosimetric parameters) and submitted to mitochondrial and caspase 3 activity tests after 1 and 3 days. Based on the results, cell viability (neutral red assay), proliferation (BrdU assay), and migration (scratch-wound assay) were evaluated using only the dosimetric parameters recommended for mucositis. Non-irradiated cells served as the control. The experiments were performed in triplicate. The 11 parameters diminished mitochondrial activity and induced tumor cell apoptosis. Using the parameters recommended for mucositis, irradiation with 780 nm (70 mW, 4 J/cm2) proved to be the safest and led to a reduction in cell viability, the induction of apoptosis, and a reduction in the migration capacity of the tumor cells.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Movimento Celular , Terapia com Luz de Baixa Intensidade , Neoplasias Bucais/patologia , Neoplasias Bucais/radioterapia , Apoptose/efeitos da radiação , Caspases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação
6.
J Biomed Mater Res B Appl Biomater ; 107(3): 680-687, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30091522

RESUMO

Leishmaniasis is a neglected disease threatening over 350 million people. Antimonials are first-line drugs due to resistance and side effects there is a demand for alternative chemotherapy. Itraconazole (ITZ) is an antimycotic. It was encapsulated into poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) and covered with mannose. The NPs were 250 nm and -1.1 mV ± 0.7. PLGA-ITZ-mannose NPs presented a toxicity of 20.7% for J774 cells, and no toxicity for THP 1. The J774 cells were infected with three Leishmania promastigotes strains and treated with ITZ loaded PLGA NPs with/without mannose. The parasite percentage of L.(V.) panamensis intracellular amastigotes significantly (p < 0.01) decreased from 34.4% to 13.7% and 5.7% for PLGA-ITZ-mannose NPs and PLGA-ITZ NPs, respectively. For L.(L.) infantum there was a reduction (p < 0.001) from 18.1% to 4.8% and 8.3% for PLGA-ITZ-mannose NPs and PLGA-ITZ NPs, respectively. Further with L.(L.) braziliensis amastigotes there was a significant reduction (p < 0.001) from 54.9% to 28% and 21.1% for PLGA-ITZ-mannose NPs and PLGA-ITZ NPs, respectively. Adding mannose increased the efficacy PLGA-ITZ NPs against L.(L.) infantum, while it had no effect against L(V.) panamensis and L.(L.) braziliensis amastigotes. We recommend further investigation of PLGA-ITZ-mannose NPs in animal models to evaluate their potential. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 00B: 000-000, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 680-687, 2019.


Assuntos
Antiprotozoários , Materiais Revestidos Biocompatíveis , Itraconazol , Leishmania/crescimento & desenvolvimento , Leishmaniose/tratamento farmacológico , Manose , Nanocápsulas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Animais , Antiprotozoários/química , Antiprotozoários/farmacocinética , Antiprotozoários/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Itraconazol/química , Itraconazol/farmacocinética , Itraconazol/farmacologia , Manose/química , Manose/farmacologia , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Células THP-1
7.
PLoS Negl Trop Dis ; 10(6): e0004754, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27303789

RESUMO

This study reports on in vitro and in vivo tests that sought to assess the antifungal activity of a newly developed magnetic carrier system comprising amphotericin B loaded onto the surface of pre-coated (with a double-layer of lauric acid) magnetite nanoparticles. The in vitro tests compared two drugs; i.e., this newly developed form and free amphotericin B. We found that this nanocomplex exhibited antifungal activity without cytotoxicity to human urinary cells and with low cytotoxicity to peritoneal macrophages. We also evaluated the efficacy of the nanocomplex in experimental paracoccidioidomycosis. BALB/c mice were intratracheally infected with Paracoccidioides brasiliensis and treated with the compound for 30 or 60 days beginning the day after infection. The newly developed amphotericin B coupled with magnetic nanoparticles was effective against experimental paracoccidioidomycosis, and it did not induce clinical, biochemical or histopathological alterations. The nanocomplex also did not induce genotoxic effects in bone marrow cells. Therefore, it is reasonable to believe that amphotericin B coupled to magnetic nanoparticles and stabilized with bilayer lauric acid is a promising nanotool for the treatment of the experimental paracoccidioidomycosis because it exhibited antifungal activity that was similar to that of free amphotericin B, did not induce adverse effects in therapeutic doses and allowed for a reduction in the number of applications.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Óxido Ferroso-Férrico/química , Nanopartículas/química , Paracoccidioidomicose/tratamento farmacológico , Alanina Transaminase/sangue , Anfotericina B/química , Animais , Antifúngicos/química , Aspartato Aminotransferases/sangue , Creatinina/sangue , Portadores de Fármacos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Paracoccidioides , Ureia/sangue
8.
J Nanobiotechnology ; 13: 36, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25966866

RESUMO

BACKGROUND: Photodynamic therapy (PDT) combines light, molecular oxygen and a photosensitizer to induce oxidative stress in target cells. Certain hydrophobic photosensitizers, such as aluminium-phthalocyanine chloride (AlPc), have significant potential for antitumor PDT applications. However, hydrophobic molecules often require drug-delivery systems, such as nanostructures, to improve their pharmacokinetic properties and to prevent aggregation, which has a quenching effect on the photoemission properties in aqueous media. As a result, this work aims to develop and test the efficacy of an AlPc in the form of a nanoemulsion to enable its use in anticancer PDT. RESULTS: The nanoemulsion was developed using castor oil and Cremophor ELP®, and a monodisperse population of nanodroplets with a hydrodynamic diameter of approximately 25 nm was obtained. While free AlPc failed to show significant activity against human breast adenocarcinoma MCF-7 cells in an in vitro PDT assay, the AlPc in the nanoemulsion showed intense photodynamic activity. Photoactivated AlPc exhibited a 50 % cytotoxicity concentration (CC50) of 6.0 nM when applied to MCF-7 cell monolayers and exerted a powerful cytotoxic effect on MCF-7 cell spheroids. CONCLUSION: Through the use of spontaneous emulsification, a stable AlPc nanoemulsion was developed that exhibits strong in vitro photodynamic activity on cancer cells.


Assuntos
Alumínio/química , Antineoplásicos/farmacologia , Emulsões/química , Indóis/química , Fotoquimioterapia/métodos , Alumínio/farmacologia , Antineoplásicos/química , Óleo de Rícino/química , Coloides/química , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Emulsões/farmacologia , Humanos , Indóis/farmacologia , Isoindóis , Células MCF-7/efeitos dos fármacos , Células MCF-7/patologia , Nanoestruturas/química , Análise Espectral Raman , Tensoativos/química
9.
Nanomedicine (Lond) ; 6(9): 1529-44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21675858

RESUMO

AIM: This work represents the first reported investigation on the effects of magnetic nanoparticles (MNPs) in nonhuman primates. Biodistribution, biocompatibility and nanotoxicity of maghemite nanoparticles stabilized with dimercaptosuccinic acid (DMSA) were accessed. MATERIALS & METHODS: A control animal was used and three other animals were intravenously injected with DMSA-MNPs and euthanized 12 h, 30 and 90 days following administration. Extracted organs were processed by histological techniques. An additional animal was used to collect blood samples to complementarily assess biocompatibility 12 h, 7, 15, 30, 60 and 90 days after DMSA-MNP injection. RESULTS: DMSA-MNPs were preferentially addressed to the lungs, liver and kidneys. Hematological and serum biochemical results corroborated histological findings, supporting DMSA-MNP biocompatibility while preserving both hepatic and renal normal activity. CONCLUSION: DMSA-MNPs were preferentially distributed to the lung, liver and kidneys. Furthermore, DMSA-MNPs were considered biocompatible, supporting their application as a promising nanomaterial platform for future biomedical use.


Assuntos
Magnetismo , Nanopartículas/química , Succímero/química , Succímero/farmacocinética , Animais , Haplorrinos , Microscopia Eletrônica de Transmissão , Nanopartículas/efeitos adversos , Nanopartículas/ultraestrutura , Succímero/efeitos adversos
10.
Cell Adh Migr ; 5(1): 29-33, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20935452

RESUMO

Magnetic nanoparticles surface-covered with meso-2,3-dimercaptosuccinic acid (MNPs-DMSA) constitute a promising approach for tissue- and cell-targeted delivery of therapeutic drugs in the lung. However, they can also induce a transient transendothelial migration of leukocytes in the organ as a side effect after endovenous administration of MNPs-DMSA. We demonstrated that monocytes/macrophages constitute the main subpopulation of leukocytes involved in this process. Our recent research found that MNPs-DMSA up-regulated the mRNA expression of E-, L- and P-selectin and macrophage-1 antigen, and increased concentration of tumor necrosis factor-α in lung, in a time dependent manner. The critical relevance of the ß2 integrin-dependent pathway in leukocyte transmigration elicited by MNPs-DMSA was demonstrated by use of knockout mice. Our work characterizes mechanisms of the pro-inflammatory effects of MNPs-DMSA in the lung, and identifies ß2 integrin-targeted interventions as promising strategies to reduce pulmonary side effects of MNPs-DMSA during biomedical applications. In addition, MNPs-DMSA could be used as modulators of lung immune response.


Assuntos
Leucócitos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas de Magnetita/administração & dosagem , Succímero/administração & dosagem , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Animais , Antígenos CD18/metabolismo , Leucócitos/metabolismo , Antígeno de Macrófago 1/efeitos dos fármacos , Antígeno de Macrófago 1/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Selectina-P/efeitos dos fármacos , Selectina-P/metabolismo , Succímero/química , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
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