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1.
Chem Biodivers ; 18(3): e2000794, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33463005

RESUMEN

The present study aimed to determine the chemical composition and biological activity of the essential oil obtained from Phyllogonium viride Brid. (Phyllogoniaceae, Bryophyta), whose samples were collected in southern Brazil. For the first time, the cytotoxic activity of the essential oil of P. viride in breast and colorectal tumor cells (MCF-7 and HCT-116) was evaluated, as well as the cytotoxic potential of this oil in non-tumoral cells of human immortalized keratinocytes (HaCaT) via MTT assay. The compounds majorly found in P. viride essential oil were ß-bazzanene (20.30 %), ß-caryophyllene (17.06 %), ß-chamigrene (14.02), and germacrene B (11.72 %). Treatment with P. viride essential oil in the different tested cell lines did not induce any toxicity in most of the tested concentrations. These data contribute to generating new scientific information about this understudied plant species. Furthermore, the chemical characterization of the compounds present in the essential oil of P. viride can lead to greater elucidation of its biotechnological potential.


Asunto(s)
Briófitas/química , Aceites Volátiles/química , Línea Celular , Humanos , Aceites Volátiles/aislamiento & purificación
2.
Microb Pathog ; 149: 104354, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32569789

RESUMEN

The immunomodulatory properties of Brazilian red propolis (BRP) have been already described. Also, propolis have been proved to have antibacterial activity on Corynebacterium pseudotuberculosis. An adjuvant effect of red propolis oil was able to induce a significant anti-C. pseudotuberculosis humoral immune response. Here, we demonstrate for the first time the immunostimulant property of BRP hydroalcoholic extract (BRPHE) in a recombinant vaccine against caseous lymphadenitis. Mice BALB/c were allocated in three groups inoculated with: sterile saline solution (G1); BRPHE (G2); or BRPHE combined with the C. pseudotuberculosis rCP01850 recombinant protein (G3) in two doses within a 21-days-interval. Blood samples were collected for the total IgG, IgG1 and IgG2a measurement. Mice were challenged with a virulent C. pseudotuberculosis strain, and other 6 mice were used for IFN-γ and IL-10 levels determination after splenocyte stimulation with the recombinant antigen. G3 showed higher significant levels of antibodies on the 42nd experimental day, with a high IgG2a/IgG1 proportion. G2 and G3 presented significant production of IFN-γ and IL-10, while G3 presented the higher levels of IFN-γ (p < 0.05). After challenge, G2 showed a survival rate of 20%, while 70% of mice from G3 survived the experimental challenge. In conclusion, BRPHE used alone has immunostimulant properties specially on cellular immune response, and when used in combination with the recombinant protein rCP01850 induces cellular and humoral immune responses as well as a significant survival of inoculated mice.


Asunto(s)
Infecciones por Corynebacterium , Corynebacterium pseudotuberculosis , Linfadenitis , Própolis , Animales , Brasil , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes/genética
3.
Bioorg Chem ; 85: 66-74, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30599414

RESUMEN

Active plant metabolites have been used as prototype drugs. In this context, Tabernaemontana catharinensis (Apocynaceae) has been highlighted because of the presence of active indole alkaloids. Thus, this study aims the bio-guided search of T. catharinensis cytotoxic alkaloids. The chemical composition was identified by high-resolution mass spectrometry, and fractionation was performed by open column and preparative thin-layer chromatography, from plant stems. The enriched fractions were tested in vitro in tumour cells A375 (melanoma cell line) and A549 (adenocarcinomic human alveolar basal epithelial cells), and non-tumour Vero cells (African green monkey kidney epithelial cells). The alkaloids identified as active were submitted to in silico toxicity prediction by ADME-Tox and OSIRIS programs and, also, to molecular docking, using topoisomerase I (PDB ID: 1SC7) by iGEMDOCK. As a result, six sub-fractions were obtained, which were identified as containing 16-epi-affinine, 12-methoxy-n-methyl-voachalotine, affinisine, voachalotine, coronaridine hydroxyindoline and ibogamine, respectively. The affinisine-containing sub-fraction showed selective toxicity against A375, with an IC50 of 11.73 µg mL-1, and no cytotoxicity against normal cells (Vero). From the in silico toxicity test results, all indole alkaloid compounds had a low toxicity risk. The molecular docking data provided structural models and binding affinities of the plant's indole alkaloids and topoisomerase I. In summary, this bio-guided search revealed that the indole alkaloids from T. catharinensis display selective cytotoxicity in A375 tumour cells and toxicity in silico. Particularly, affinisine might be a chemotherapeutic for A375 melanoma cells.


Asunto(s)
Antineoplásicos/farmacología , Alcaloides Indólicos/farmacología , Tabernaemontana/química , Animales , Antineoplásicos/aislamiento & purificación , Antineoplásicos/toxicidad , Línea Celular Tumoral , Chlorocebus aethiops , ADN-Topoisomerasas de Tipo I/metabolismo , Teoría Funcional de la Densidad , Humanos , Alcaloides Indólicos/aislamiento & purificación , Alcaloides Indólicos/toxicidad , Modelos Químicos , Simulación del Acoplamiento Molecular , Tallos de la Planta/química , Células Vero
4.
Bioorg Chem ; 90: 103079, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31255990

RESUMEN

Plant compounds have been identified as new drug prototypes. In this line, this work aimed to isolate the indole alkaloid affinisine from Tabernaemontana catharinensis and test its antitumor activity. The alkaloid was isolated by silica gel open column chromatography from the ethanolic extract of the stem of T. catharinensis. Afterwards, this molecule was characterized by high-resolution mass spectrometry and nuclear magnetic resonance. In the next step, the cytotoxicity of the compound was tested against human melanoma cell lines (A375, WM1366 and SK-MEL-28) and a normal skin cell line (CCD-1059Sk) using a MTT (3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Cells treated with affinisine were evaluated by flow cytometry to analyze apoptosis and the induction of cell cycle arrest, to evaluate the dead mechanism. The metabolite was isolated in a 0.2% yield relative to the extract. Cytotoxic activity of the molecule was observed at 48 h, resulting in considerable growth inhibition rates in melanoma cells, especially in WM1366, which had the lowest IC50 (32.86 ± 2.54 µg/mL). The apoptosis rate was lower in A375 (56.66 and 86.71% with 57 and 65 µg/mL, respectively). Moreover, affinisine was able to significantly induce cell cycle arrest in different phases in the A375 and WM1366 cell lines. However, in SK-MEL-28 cells, cycle arrest was not observed. In summary, this compound significantly decreased the viability of tumor cells in a dose- and time-dependent manner for all evaluated lineages, reduced cell viability by the apoptosis mechanism and presented prominent activities of cell cycle arrest. In this way, the use of antineoplastic agents is among the most widely used therapeutic measures for the control and treatment of cancer. Affinisine is a promising prototype in the search for new drugs to treat cancer.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Alcaloides Indólicos/aislamiento & purificación , Alcaloides Indólicos/farmacología , Melanoma/tratamiento farmacológico , Extractos Vegetales/farmacología , Tabernaemontana/química , Apoptosis , Puntos de Control del Ciclo Celular , Supervivencia Celular , Humanos , Técnicas In Vitro , Melanoma/patología , Células Tumorales Cultivadas
5.
An Acad Bras Cienc ; 88(1): 281-92, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26839997

RESUMEN

Salvia officinalis (Lamiaceae) has been used in south of Brazil as a diary homemade, in food condiment and tea-beverage used for the treatment of several disorders. The objective of this study was to characterize chemical compounds in the hydroalcoholic (ExtHS) and aqueous (ExtAS) extract from Salvia officinalis (L.) by gas chromatography-mass spectrometry (GC-MS) and by high-resolution electrospray ionization mass spectrometry (ESI-QTOF MS/MS), evaluate in vitro ability to scavenge the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), catalase (CAT-like) and superoxide dismutase (SOD-like) activity, moreover cytotoxic by MTT assay, alterations on cell morphology by giemsa and apoptotic-induced mechanism for annexin V/propidium iodide. Chemical identification sage extracts revealed the presence of acids and phenolic compounds. In vitro antioxidant analysis for both extracts indicated promising activities. The cytotoxic assays using tumor (Hep-2, HeLa, A-549, HT-29 and A-375) and in non-tumor (HEK-293 and MRC-5), showed selectivity for tumor cell lines. Immunocytochemistry presenting a majority of tumor cells at late stages of the apoptotic process and necrosis. Given the results presented here, Brazilian Salvia officinalis (L.) used as condiment and tea, may protect the body against some disease, in particularly those where oxidative stress is involved, like neurodegenerative disorders, inflammation and cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Extractos Vegetales/farmacología , Salvia officinalis/química , Línea Celular Tumoral/efectos de los fármacos , Proliferación Celular , Cromatografía de Gases y Espectrometría de Masas , Humanos , Inmunohistoquímica , Estrés Oxidativo/efectos de los fármacos
6.
An Acad Bras Cienc ; 86(4): 1907-14, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25590726

RESUMEN

Biflorin is an o-naphthoquinone with proven cytotoxic effects on tumor cells showing antimicrobial, antitumor and antimutagenic activities. Biflorin is an isolated compound taken from the roots of the plant Capraria biflora L. (Schrophulariaceae), indigenous of the West Indies and South America, which is located in temperate or tropical areas. This compound has shown to be strongly active against grampositive and alcohol-acid-resistant bacteria. It has been efficient in inhibiting the proliferation tumor cell lines CEM, HL-60, B16, HCT-8 and MCF-7. Recently, SK-Br3 cell line was treated with biflorin showing important cytotoxic effects. In this article, information related to the first structural characterization studies are presented, as well as the latest reports concerning the biological activity of this molecule.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Naftoquinonas/farmacología , Scrophulariaceae/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Humanos , Naftoquinonas/química , Naftoquinonas/aislamiento & purificación
7.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39065804

RESUMEN

A new series of compounds planned by molecular hybridization of the nucleobases uracil and thymine, or the xanthine theobromine, with coumarins, and linked through 1,2,3-triazole heterocycles were evaluated for their in vitro anticancer activity against the human tumor cell lines: colon carcinoma (HCT116), laryngeal tumor cells (Hep-2), and lung carcinoma cells (A549). The hybrid compound 9a exhibited better activity in the series, showing an IC50 of 24.19 ± 1.39 µM against the HCT116 cells, with a selectivity index (SI) of 6, when compared to the cytotoxicity against the non-tumor cell line HaCat. The in silico search for pharmacological targets was achieved through molecular docking studies on all active compounds, which suggested that the synthesized compounds possess a high affinity to the Topoisomerase 1-DNA complex, supporting their antitumor activity. The in silico toxicity prediction studies suggest that the compounds present a low risk of causing theoretical mutagenic and tumorigenic effects. These findings indicate that molecular hybridization from natural derivative molecules is an interesting approach to seek new antitumor candidates.

8.
ACS Biomater Sci Eng ; 10(3): 1808-1818, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38411100

RESUMEN

Bacteria are an old concern to human health, as they are responsible for nosocomial infections, and the number of antibiotic-resistant microorganisms keeps growing. Copper is known for its intrinsic biocidal properties, and therefore, it is a promising material to combat infections when added to surfaces. However, its biocidal properties in the presence of light illumination have not been fully explored, especially regarding the use of microsized particles since nanoparticles have taken over all fields of research and subjugated microparticles despite them being abundant and less expensive. Thus, the present work studied the bactericidal properties of metallic copper particles, in microscale (CuMPs) and nanoscale (CuNPs), in the absence of light and under white LED light illumination. The minimum bactericidal concentration (MBC) of CuMPs against Staphylococcus aureus that achieved a 6-log reduction was 5.0 and 2.5 mg mL-1 for assays conducted in the absence of light and under light illumination, respectively. Similar behavior was observed against Escherichia coli. The bactericidal activity under illumination provided a percentage increase in log reduction values of 65.2% for S. aureus and 166.7% for E. coli when compared to the assays under dark. This assay reproduced the testing CuNPs, which showed superior bactericidal activity since the concentration of 2.5 mg mL-1 promoted a 6-log reduction of both bacteria even under dark. Its superior bactericidal activity, which overcame the effect of illumination, was expected once the nanoscale facilitated the interaction of copper within the surface of bacteria. The results from MBC were supported by fluorescence microscopy and atomic absorption spectroscopy. Therefore, CuMPs and CuNPs proved to have size- and dose-dependent biocidal activity. However, we have shown that CuMPs photoactivity is competitive compared to that of CuNPs, allowing their application as a self-cleaning material for disinfection processes assisted by conventional light sources without additives to contain the spread of pathogens.


Asunto(s)
Cobre , Staphylococcus aureus , Humanos , Cobre/farmacología , Cobre/química , Escherichia coli , Iluminación , Antibacterianos/farmacología , Antibacterianos/química , Bacterias
9.
J Pathol ; 221(4): 462-70, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20593486

RESUMEN

'Field cancerization' in head and neck squamous cell carcinoma (HNSCC) is poorly understood and it may extend from the pharynx into the oesophagus. Both local recurrences and second primary carcinomas/second field tumours may originate from field cancerization. Our prospective pilot study aimed at the identification of patients suffering from field cancerization on the basis of mucosal protein profiles. Five mucosal biopsies from the oropharynx, hypopharynx and from three regions of the oesophagus were taken from 24 patients. Protein profiles were generated from the mucosal biopsies. After classifier learning, using the profiles of the patients without tumour diagnosis (n = 9), we were able to discriminate between the different mucosal sites and between healthy mucosa and HNSCC using tumour and healthy tissue samples. Mucosal biopsies of tumour patients (n = 15) revealed changes in the protein profiles similar to those in the tumours. During 42 months median follow-up, six tumour patients experienced local recurrences and second field tumours, of which three occurred in the oesophagus. In all six cases, tumour relapse was correctly predicted by altered mucosal protein profiles (p = 0.007, Fisher's exact test, two-tailed). Consequently, molecular field cancerization had a strong impact on progression-free survival (p = 0.007, log-rank test). Protein profiles of small diagnostic biopsies hold great promise to improve personalized risk assessment in HNSCC. Larger studies are needed to further substantiate these findings.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Faríngeas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Métodos Epidemiológicos , Neoplasias Esofágicas/patología , Humanos , Membrana Mucosa/metabolismo , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Neoplasias Faríngeas/patología , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
10.
Materials (Basel) ; 14(11)2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34072271

RESUMEN

Wound infections are the main complication when treating skin wounds. This work reports a novel antimicrobial material using green synthesized zinc oxide nanoparticles (ZnONPs) incorporated in polymeric fibers for wound healing purposes. ZnONPs are a promising antimicrobial nanomaterial with high activity against a range of microorganisms, including drug-resistant bacteria. The electrospun fibers were obtained using polyacrylic acid (PAA) and polyallylamine hydrochloride (PAH) and were loaded with ZnONPs green synthesized from Ilex paraguariensis leaves with a spherical shape and ~18 nm diameter size. The fibers were produced using the electrospinning technique and SEM images showed a uniform morphology with a diameter of ~230 nm. EDS analysis proved a consistent dispersion of Zn in the fiber mat, however, particle agglomerates with varying sizes were observed. FTIR spectra confirmed the interaction of PAA carboxylic groups with the amine of PAH molecules. Although ZnONPs presented higher antimicrobial activity against S. aureus than E. coli, resazurin viability assay revealed that the PAA/PAH/ZnONPs composite successfully inhibited both bacteria strains growth. Photomicrographs support these results where bacteria clusters were observed only in the control samples. The PAA/PAH/ZnONPs composite developed presents antimicrobial activity and mimics the extracellular matrix morphology of skin tissue, showing potential for wound healing treatments.

11.
ACS Biomater Sci Eng ; 7(8): 3683-3695, 2021 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-34291900

RESUMEN

Ti6Al4V is one of the most lightweight, mechanically resistant, and appropriate for biologically induced corrosion alloys. However, surface properties often must be tuned for fitting into biomedical applications, and therefore, surface modification is of paramount importance to carry on its use. This work compares the interaction between two different cell lines (L929 fibroblasts and osteoblast-like MG63) and medical grade Ti6Al4V after surface modification by plasma nitriding or thin film deposition. We studied the adhesion of these two cell lines, exploring which trends are consistent for cell behavior, correlating with osseointegration and in vivo conditions. Modified surfaces were analyzed through several physicochemical characterization techniques. Plasma nitriding led to a more pronounced increase in surface roughness, a thicker aluminum-free layer, made up of diverse titanium nitride phases, whereas thin film deposition resulted in a single-phase pure titanium nitride layer that leveled the ridged topography. The selective adhesion of osteoblast-like cells over fibroblasts was observed in nitrided samples but not in thin film deposited films, indicating that the competitive cellular behavior is more pronounced in plasma nitrided surfaces. The obtained coatings presented an appropriate performance for its use in biomedical-aimed applications, including the possibility of a higher success rate in osseointegration of implants.


Asunto(s)
Materiales Biocompatibles Revestidos , Aleaciones , Corrosión , Propiedades de Superficie , Línea Celular , Animales , Ratones , Humanos
12.
Artículo en Inglés | MEDLINE | ID: mdl-34454693

RESUMEN

The sodium valproate has been largely used as an anti-epilepsy drug and, recently, as a putative drug in cancer therapy. However, the treatment with sodium valproate has some adverse effects. In this sense, more effective and secure complexes than sodium valproate should be explored in searching for new active drugs. This study aims to evaluate the cytotoxicity of sodium valproate, mixed ternary mononuclear Cu(II) complexes based on valproic acid (VA) with 1,10-phenanthroline (Phen) or 2,2'- bipyridine (Bipy) ligands - [Cu2(Valp)4], [Cu(Valp)2Phen] and [Cu(Valp)2Bipy] - in yeast Saccharomyces cerevisiae, proficient or deficient in different repair pathways, such as base excision repair (BER), nucleotide excision repair (NER), translesion synthesis (TLS), DNA postreplication repair (PRR), homologous recombination (HR) and non-homologous end-joining (NHEJ). The results indicated that the Cu(II) complexes have higher cytotoxicity than sodium valproate in the following order: [Cu(Valp)2Phen] > [Cu(Valp)2Bipy] > [Cu2(Valp)4] > sodium valproate. The treatment with Cu(II) complexes and sodium valproate induced mutations in S. cerevisiae. The data indicated that yeast strains deficient in BER (Ogg1p), NER (complex Rad1p-Rad10p) or TLS (Rev1p, Rev3p and Rad30p) proteins are associated with increased sensitivity to sodium valproate. The BER mutants (ogg1Δ, apn1Δ, rad27Δ, ntg1Δ and ntg2Δ) showed increased sensitivity to Cu(II) complexes. DNA damage induced by the complexes requires proteins from NER (Rad1p and Rad10p), TLS (Rev1p, Rev3p and Rad30p), PRR (Rad6 and Rad18p) and HR (Rad52p and Rad50p) for efficient repair. Therefore, Cu(II) complexes display enhanced cytotoxicity when compared to the sodium valproate and induce distinct DNA lesions, indicating a potential application as cytotoxic agents.


Asunto(s)
Cobre/farmacología , Reparación del ADN/efectos de los fármacos , Preparaciones Farmacéuticas/administración & dosificación , Fenantrolinas/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Ácido Valproico/farmacología , ADN/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Ligandos , Mutación/efectos de los fármacos , Recombinación Genética/efectos de los fármacos
13.
J Biomater Appl ; 36(2): 252-263, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33906516

RESUMEN

Given the global panorama of demands in the health area, the development of biomaterials becomes irreducible for the maintenance and/or improvement in the quality of life of the human being. Aiming to reduce the impacts related to infections in the healing processes of the dermal structure, the present work proposes the development of polydimethylsiloxane (PDMS) based membranes with the incorporated polyhexamethylenebiguanide (PHMB) antimicrobial agent. In the present study, the antimicrobial and antibiofilm properties of polydimethylsiloxane (PDMS) films incorporated with 0.1, 0.3, and 0.5% (w/w) of polyhexamethylene biguanide (PHMB) were evaluated, aiming the development of a protective biomaterial that avoids cutaneous infections from the autochthonous and allochthonous microbiota. The disk diffusion of PHMB-loaded PDMS has shown the growth inhibition of Escherichia coli (ATCC 9637), Pseudomonas aeruginosa (ATCC 27953), Acinetobacter baumannii (ATCC 19606), Staphylococcus aureus (ATCC 6538), Staphylococcus epidermidis (ATCC 12228), Streptococcus pyogenes (ATCC 19615), Bacillus subtilis (ATCC 6633) and also yeast-like fungi Candida albicans, all microorganisms found on the epidermal surface. Likewise, the present study demonstrated low cytotoxicity of the PHMB-loaded PDMS on HaCaT and L929 cells at lower concentrations (0.1% w/w), indicating the possibility of using the developed material as a dressing for wounds, burns, and post-surgical procedures.


Asunto(s)
Antiinfecciosos/química , Dimetilpolisiloxanos/química , Guanidinas/química , Animales , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Guanidinas/metabolismo , Guanidinas/farmacología , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología
14.
Environ Sci Pollut Res Int ; 28(48): 69416-69425, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34302239

RESUMEN

Nanoparticles such as zinc oxide nanoparticles (ZnO-NP) that are incorporated in consumer and industrial products have caused concern about their potential ecotoxicological impact when released into the environment. Bivalve mollusks are susceptible targets for nanoparticle toxicity since nanomaterials can enter the cells by endocytosis mechanisms. The aim of this study was to evaluate the influence of ZnO-NP on the redox metabolism in Limnoperna fortunei and the DNA damage after exposure to ZnO-NP. Adult bivalves were incubated with 1-, 10-, and 50-µg mL-1 ZnO-NP for 2, 4, and 24 h. Ionic Zn release, enzymatic and non-enzymatic antioxidant activity, oxidative damage, and DNA damage were evaluated. Oxidative damage to proteins and lipids were observed after 4-h exposure and returned to baseline levels after 24 h. Superoxide dismutase levels decreased after 4-h exposure and increased after 24 h. No significant alteration was observed in the catalase activity or even DNA double-strand cleavage. The dissociation of ZnO may occur after 24 h, releasing ionic zinc (Zn2+) by hydrolysis, which was confirmed by the increase in the ionic Zn concentration following 24-h exposure. In conclusion, ZnO-NP were able to induce oxidative stress in exposed golden mussels. The golden mussel can modulate its own antioxidant defenses in response to oxidative stress and seems to be able to hydrolyze the nanoparticles and consequently, release Zn2+ into the cellular compartment.


Asunto(s)
Nanopartículas del Metal , Mytilidae , Nanopartículas , Óxido de Zinc , Animales , Oxidación-Reducción , Estrés Oxidativo
15.
J Biomater Appl ; 35(3): 353-370, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32571172

RESUMEN

Ti6Al4V used in biomedical applications still has several surface-related problems, such as poor bone compatibility and low wear resistance. In this work, the formation of a protective layer of titanium nitride obtained by plasma treatment in hollow cathode was studied, and the best experimental conditions were verified by a statistical factorial design of experiments. The samples were characterized in terms of their physical and chemical properties, correlating the effects of time (min) and temperature (°C). An achieved ideal condition was further analysed in terms of in vitro cytotoxicity, micro-abrasion, and electrochemical properties. The carried-out assessment has shown that nitrided condition has an improvement in wettability, microhardness, along with TixNy formation and roughness increment, when compared to pristine condition.


Asunto(s)
Aleaciones/química , Materiales Biocompatibles Revestidos/química , Gases em Plasma/química , Titanio/química , Animales , Supervivencia Celular , Corrosión , Técnicas Electroquímicas , Electrodos , Humanos , Ratones , Propiedades de Superficie , Temperatura , Factores de Tiempo , Humectabilidad
16.
Mater Sci Eng C Mater Biol Appl ; 96: 539-551, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30606564

RESUMEN

Biomaterials can be applied in tissue engineering as scaffolds that resemble the extracellular matrix functioning as a temporary structure for cell proliferation and reconstruction of new organs and tissues. To evaluate the potential use of scaffolds as a biomaterial, this work proposes the development and characterization of polyurethane (PU), poly(D,L-lactic acid) (PDLLA) and polyurethane/poly(d,l-lactic acid) (PU/PDLLA) scaffolds produced by gas foaming technique. The neat polymers and the blends were characterized, in film form, by gel permeation chromatography (GPC), thermogravimetry (TG), differential scanning calorimetry (DSC) and field emission gun scanning electron microscopy (FEG-SEM). After supercritical fluid technology, in scaffolds form, the samples were characterized by FEG-SEM, pore size, density, cytotoxicity and cell adhesion. For film characterization the PU/PDLLA sample presented intermediate characteristics compared to the neat polymers, exhibiting the behavior of both polymers in the sample without phase separation in the FEG-SEM micrograph and bimodal molar weight distribution by GPC. The scaffolds showed interconnectivity and pore size of 141 µm ±â€¯108 µm for PUsc and 52 µm ±â€¯32 µm for PDLLAsc. The PU/PDLLAsc exhibited a bimodal structure in which the PU in the mixture revealed pores of 75 µm ±â€¯57 µm, while for PDLLA, the pore size was 19 µm ±â€¯12 µm. In vitro tests confirmed the adhesion of L929 cells to PUsc, PDLLAsc and PU/PDLLAsc, showing no cytotoxic effect. Finally, it can be concluded that it is possible to produce PU, PDLLA and PU/PDLLA scaffolds by supercritical fluid, which may be applied as biomaterials.


Asunto(s)
Ensayo de Materiales , Poliésteres , Poliuretanos , Andamios del Tejido/química , Animales , Investigación Biomédica , Línea Celular , Ratones , Poliésteres/química , Poliésteres/farmacología , Poliuretanos/química , Poliuretanos/farmacología
17.
Biomed Pharmacother ; 112: 108640, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30784929

RESUMEN

Since early times, propolis has been used in folk medicine. The red propolis, collected in the northeast region of Brazil has been highlighted due to its popular use as an antimicrobial, with anti-inflammatory and healing properties, which are associated with its chemical composition. Here, we combine a bacterial membrane with red propolis to treat wounds of diabetic mice. This work aims to evaluate a biocurative from bacterial cellulose associated with red propolis in diabetic mice as wound healing model. Biocuratives from bacterial cellulose membrane and different extracts of red propolis were produced. The qualification and quantification of the presence of propolis chemical compounds in the membrane were investigated through high-resolution mass spectrometry (HRMS). Tests in vivo with biocuratives were performed on Swiss male diabetic mice induced by estroptozotocin. The animals were submitted to a surgical procedure and a single lesion was produced in the dorsal region, which was treated with the biocuratives. Macroscopic assessments were performed at 2, 7 and 14 postoperative days, and biopsies were collected on days 0, 7 and 14 for histological analysis, myeloperoxidase enzyme activity (MPO) and cytokines (TNF-α, IL-1ß, and TGF-ß). Altogether, ten compounds were identified in membranes and five were further quantified. The ethyl acetate extract showed more red propolis markers, and the most prevalent compound was Formononetin with 4423.00-2907.00 µg.g-1. Macroscopic analyses demonstrated that the two groups treated with red propolis (GMEBT and GMEAE) showed significantly greater healing capabilities compared to the control groups (GS and GMS). An increase in leukocyte recruitment was observed, confirmed by the activity of the enzyme myeloperoxidase (MPO) in GMEBT and GMEAE groups. The levels of TNF-α were significantly higher in wounds stimulated with red propolis, as well as in TGF-ß (GMEBT and GMEAE) on day 7. This was different from the IL-1ß levels that were higher in the control groups (GS and GMS). In summary, the biocuratives produced in this work were able to accelerate the wound healing process in a diabetic mouse model. In this way, the traditional knowledge of red propolis activity helped to create a biotechnological product, which can be used for diabetic wound healing purpose.


Asunto(s)
Acetobacteraceae/química , Celulosa/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Própolis/uso terapéutico , Piel/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Animales , Membrana Celular/química , Celulosa/administración & dosificación , Celulosa/aislamiento & purificación , Diabetes Mellitus Experimental/complicaciones , Masculino , Própolis/administración & dosificación , Piel/lesiones , Resultado del Tratamiento
18.
Mater Sci Eng C Mater Biol Appl ; 102: 264-275, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31146999

RESUMEN

Ultra-high molecular weight polyethylene (UHMWPE) is a prevailing bearing material applied in joint arthroplasty. Despite not being a novel biomaterial, its debris as consequence of long application and surface properties usually still lead to short lifespan. Many of the drawbacks are associated with sterilization methods that degrade the surface properties of UHMWPE. This work aims at improving the sterilizing treatment and also increasing material wettability, without losing bulk properties, which are essential for an orthopedic bearing. Cold plasma in hollow cathode setting was used for the material surface functionalization. Samples were characterized through contact angle (WCA), x-ray diffraction (XRD), optical microscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and profilometry. Optimal points based on immediate surface wettability, shelf time and sterilization efficacy were chosen for biocompatibility evaluation. When comparing cell viability through MTT among treated samples (OP1, OP2 and UV), a slight reduction in OP2 viability could be seen after 7 days incubation, which is also observed in Giemsa staining and SEM images. In late incubation, OP1 loses its hydrophilic character and displays higher cell adhesion than its counterparts UV and OP2. At the end, OP2 showed less cells growing over the biomaterial after 7 days exposition compared to OP1 and UV. OP1 presented a more hydrophobic surface and improved cell adhesion, differently from OP2 and UV, which maintained their wettability conditions in late incubation. Cell analysis results indicate that surface wetting influences cell morphology and consequent cell adhesion, in which more hydrophobic surfaces are shown to favor fibroblast adhesion properties.


Asunto(s)
Fenómenos Químicos , Fibroblastos/citología , Gases em Plasma/química , Polietilenos/química , Esterilización , Análisis de Varianza , Animales , Apoptosis , Adhesión Celular , Línea Celular , Proliferación Celular , Forma de la Célula , Supervivencia Celular , Electrodos , Fibroblastos/ultraestructura , Ratones
19.
J Ethnopharmacol ; 239: 111863, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30974203

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Ethnopharmacological knowledge is important for the identification of active compounds from natural products. Pain may have different aetiologies with complex mechanisms. Tabernaemontana catharinensis A. DC. is well known for indole alkaloids, being used empirically in folk medicine, with antimicrobial and anti-inflammatory as well as antiofidic actions among others. AIM OF THE STUDY: This work aims to evaluate the antinociceptive and antioxidant effect in mice of the alkaloids extract from leaves of Tabernaemontana catharinensis A. DC. (AITc). MATERIALS AND METHODS: The AITc was produced by ultrasound and acid-base extraction, and the chemical composition was evaluated by high resolution mass spectrometry. Male mice (Mus musculus), Swiss, were used for in vivo tests. The AITc was administrated at doses of 1.0, 5.0, and 10.0 mg/kg in acetic acid model, formalin, tail-immersion, hot plate, and open field tests, and compared to saline, morphine, or diazepam controls, depending on the test. The toxicological, biochemical, haemogram and antioxidant effect were evaluated in mouse organs such as liver, brain, kidneys, spleen and stomach. RESULTS: In total, 10 compounds were identified in the AITc, being from the indole alkaloids from the ibogan and corynanthean classes. The extract in doses ranging from 5.0 to 10.0 mg/kg showed an antinociceptive effect for acetic acid, inhibiting by 47.7% and 61.6%. In the same line, reductions of 47.1% (first phase) and 43.6% (second phase) were observed for the 5.0 mg/kg dose in the formalin test. However, tail-immersion and hot plate tests did not show considerable modifications in the latency period, while in the open field test there was an inhibition of only 5.1%. It was observed no differences in NO levels and total antioxidant status of the mice in any of the studie tissues. CONCLUSIONS: The results justify the use of this plant in traditional medicine. in vivo tests indicate that these compounds possess central and peripheral mechanisms of action. This is study that reports the nociceptive action of these alkaloids, also including toxicity tests, which are intended to guarantee the safety of use of extracts of this plant.


Asunto(s)
Alcaloides , Analgésicos , Antioxidantes , Extractos Vegetales , Tabernaemontana , Ácido Acético , Alcaloides/química , Alcaloides/uso terapéutico , Analgésicos/química , Analgésicos/uso terapéutico , Animales , Antioxidantes/química , Antioxidantes/uso terapéutico , Compuestos de Bifenilo/química , Masculino , Ratones , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Hojas de la Planta , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subcrónica
20.
Microbiol Res ; 214: 74-82, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30031483

RESUMEN

The indiscriminate use of antibiotics is causing an increase in bacterial resistance, complicating therapeutic planning. In this context, natural products have emerged as major providers of bioactive compounds. This work performs a bioguided study of Brazilian red propolis to identify compounds with antibacterial potential and to evaluate their cytotoxicity against non-tumour cells. Using bioguided fractionation performed with the hydroalcoholic extract of red propolis from Alagoas, it was possible to obtain subfractions with remarkable bacteriostatic activity compared with the precursor fractions. The SC2 subfraction was highlighted and showed the best results with minimal inhibitory concentrations (MICs) of 56.75, 28.37, 454.00, and 227.00 µg mL-1 against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa, respectively. However, this study also revealed a cytotoxic effect against the non-tumour Vero cell line. Furthermore, through chemical analyses using high resolution mass spectrometry, high performance liquid chromatography with UV detection, and gas chromatography coupled to mass spectrometry, we verified the presence of important marker compounds in the fractions and extracts, including formononetin (m/z 267.0663), biochanin A (m/z 283.0601), and liquiritigenin (m/z 255.0655). The results obtained in this study suggest an important antibacterial potential of red propolis subfractions. In this context, the bioguided fractionation has been a useful process, due to its ability to isolate and concentrate active compounds in a logical and rational way.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Própolis/química , Animales , Antibacterianos/toxicidad , Bacterias/crecimiento & desarrollo , Productos Biológicos/toxicidad , Brasil , Supervivencia Celular/efectos de los fármacos , Fraccionamiento Químico , Chlorocebus aethiops , Cromatografía Líquida de Alta Presión , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Células Vero
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