RESUMEN

In this study, we report the synthesis and characterization of pH-responsive nanoconjugates for targeted drug delivery. Galactomannan extracted from D. regia seeds was oxidized to form aldehyde groups, achieving a percentage of oxidation of 25.6 %. The resulting oxidized galactomannan (GMOX) was then copolymerized with PINIPAm-NH2, yielding a copolymer. The copolymer exhibited signals from both GMOX and PNIPAm-NH2 in its NMR spectrum, confirming successful copolymerization. Critical association concentration (CAC) studies revealed the formation of nanostructures, with lower CAC values observed at higher temperatures. The copolymer and GMOX reacted with doxorubicin (DOX), resulting in nanoconjugates with controlled drug release profiles, especially under acidic conditions similar to tumor microenvironments. Cytotoxicity assays demonstrated significant efficacy of the nanoconjugates against melanoma cells with reduced toxicity towards healthy cells. These findings underscore the potential of the pH-responsive nanoconjugates as promising candidates for targeted cancer therapy, offering improved therapeutic efficacy and reduced systemic side effects.

Asunto(s)

Doxorrubicina , Galactosa , Mananos , Nanoconjugados , Doxorrubicina/farmacología , Doxorrubicina/química , Mananos/química , Mananos/farmacología , Galactosa/química , Galactosa/análogos & derivados , Humanos , Nanoconjugados/química , Concentración de Iones de Hidrógeno , Liberación de Fármacos , Línea Celular Tumoral , Portadores de Fármacos/química , Supervivencia Celular/efectos de los fármacos , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Antineoplásicos/química , Antineoplásicos/farmacología

RESUMEN

The understanding of cancer immunity and antitumor factors generated by natural polysaccharides is not yet fully comprehended. Polysaccharides, like cashew gum (CG), can exhibit immunomodulatory action and may assist in the antitumor process and side effects relieve. This study aimed to determine the antitumor effect of CG alone or in combination with cyclophosphamide (CTX), and its interactions with immune cells, in a murine melanoma model, using the B16-F10 cell line. Tumor growth inhibition, hematological, histopathological, ELISA, flow cytometry, immunofluorescence, and qRT-PCR analyses were performed to elucidate the antitumor potential, involvement of immune cells, and potential toxic effects. CG showed significant tumor growth inhibition, reaching up to 42.9 % alone and 51.4 % in combination with CTX, with mild toxicity to organs. CG enhanced leukocyte count, even in the presence of CTX. Furthermore, CG influenced the activation of tumor-associated macrophages (TAM), characterized by an increase in Il4, as well as a reduction in Ifng, Il1b, Tgfb, and Il6 gene expression. Nevertheless, these effects did not compromise the antitumor activity of CG. In summary, the combination of CG with CTX is a promising approach for leukopenia, one of the most important side effects of cancer treatment and deserves further investigation.

Asunto(s)

Anacardium , Ciclofosfamida , Melanoma Experimental , Animales , Ciclofosfamida/farmacología , Ratones , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Anacardium/química , Gomas de Plantas/química , Gomas de Plantas/farmacología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Citocinas/metabolismo , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología

RESUMEN

OBJECTIVES: Angico gum (AG) (Anadenanthera colubrina var. Cebil [Griseb.] Altschul) is utilized by some Brazilian communities to alleviate symptoms from gastroesophageal reflux disease. Here, we aimed to investigate the "in vitro" topical protective capacity of AG on human esophageal mucosa. METHODS: Biopsies of the distal esophageal mucosa were collected from 35 patients with heartburn (24 non-erosive and 11 with erosive oesophagitis (EE)) and mounted in Üssing chambers. AG was applied topically, followed by exposure with acid solution (pH 2.0 or pH 1.0), where transepithelial electrical resistance (TER) and The transepithelial permeability for fluorescein was assessed. The incubation of the AG labeled with FITC in the esophageal mucosa was localized by fluorescence microscopy. KEY FINDINGS: Pretreatment with AG prevented the drop in TER induced by acid solution, as well as significantly decreases the fluorescein permeability in non-erosive patients. The protective effect of AG was sustained for up to 120 min both in biopsies of non-erosive and erosive esophagitis. Confocal microscope images showed mucosal luminal adherence of FITC-labeled AG. CONCLUSION: AG had a prolonged topical protective effect against acid solution in mucosal biopsies of patients with non-erosive and erosive esophagitis.

Asunto(s)

Mucosa Esofágica , Reflujo Gastroesofágico , Humanos , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/prevención & control , Mucosa Esofágica/efectos de los fármacos , Mucosa Esofágica/patología , Mucosa Esofágica/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Adulto , Permeabilidad , Impedancia Eléctrica , Administración Tópica , Biopolímeros , Anciano , Fluoresceína/administración & dosificación , Esófago/efectos de los fármacos , Esófago/patología , Esófago/metabolismo , Pirosis/tratamiento farmacológico , Pirosis/prevención & control , Relevancia Clínica

RESUMEN

The present work explores the esterification reaction in the polysaccharide extracted from the seaweed Gracilaria birdiae and investigates its antioxidant potential. The reaction process was conducted with phthalic anhydride at different reaction times (10, 20 and 30 min), using a molar ratio of 1:2 (polymer: phthalic anhydride). Derivatives were characterized by FTIR, TGA, DSC and XRD. The biological properties of derivatives were investigated by assays of cytotoxicity and antioxidant activity (2,2-diphenyl-1-picrylhydroxyl - DPPH and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt - ABTS). The results obtained by FT-IR confirmed the chemical modification, there was a reduction related to the presence of carbonyl and hydroxyl groups when compared to the in nature polysaccharide spectrum. TGA analysis showed a change in the thermal behavior of the modified materials. X-ray diffraction, it was shown that the in nature polysaccharide appeared as an amorphous material, while the material obtained after the chemical modification process had increased crystallinity, due to the introduction of phthalate groups. For the biological assays, it was observed that the phthalate derivative was more selective than the unmodified material for the murine metastatic melanoma tumor cell line (B16F10), revealing a good antioxidant profile for DPPH and ABTS radicals.

Asunto(s)

Antineoplásicos , Gracilaria , Animales , Ratones , Antioxidantes/química , Anhídridos Ftálicos , Galactanos , Espectroscopía Infrarroja por Transformada de Fourier , Antineoplásicos/química , Polisacáridos/química

RESUMEN

Lemon gum (LG) obtained from Citrus × latifolia in Brazil was isolated and characterized. In addition, gum biocompatibility was evaluated in vitro and in vivo by Galleria mellonella and mice model. The cytotoxicity against tumor cells was also evaluated. The ratio of arabinose:galactose: rhamnose:4-OMe-glucuronic acid was 1:0.65:0.06:0.15. Small traces of protein were detected, emphasizing the isolate purity. Molar mass was 8.08 × 105 g/mol, with three different degradation events. LG showed antiproliferative activity against human prostate adenocarcinoma cancer cells, with percentage superior to 50 %. In vivo toxicity models demonstrated that LG is biocompatible polymer, with little difference in the parameters compared to control group. These results demonstrate advance in the study of LG composition and toxicity, indicating a potential for several biomedical and biotechnological future applications.

Asunto(s)

Adenocarcinoma , Citrus , Masculino , Animales , Ratones , Humanos , Próstata , Galactanos , Adenocarcinoma/tratamiento farmacológico

RESUMEN

OBJECTIVE: This study aimed to evaluate the in vivo protective effect of the angico gum biopolymer in reducing the inflammatory response and preserving the integrity of the laryngeal and esophageal mucosa. STUDY DESIGN: Animal study. METHODS: A murine surgical model of gastroesophageal reflux disease was accomplished and subsequently treated with angico gum or omeprazole. On days 3 and 7 post surgery, samples of the larynx and esophagus, respectively, were collected to measure the level of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and mucosal permeability to fluorescein). RESULTS: Angico gum and omeprazole decreased laryngeal inflammation (wet weight and myeloperoxidase activity) and dramatically improved the integrity of the laryngeal mucosa. It also reduced inflammation (decreased wet weight and myeloperoxidase activity) of the esophagus and preserved the barrier function (inferred by assessing the integrity of the mucosa). CONCLUSION: This study demonstrates the protective effect of angico gum in an experimental gastroesophageal reflux disease model. Angico gum attenuates inflammation and impairment of the mucosal barrier function not only in the larynx but also in the esophagus. LEVEL OF EVIDENCE: NA Laryngoscope, 133:162-168, 2023.

Asunto(s)

Mucosa Esofágica , Reflujo Gastroesofágico , Ratones , Animales , Reflujo Gastroesofágico/tratamiento farmacológico , Impedancia Eléctrica , Membrana Mucosa , Modelos Animales de Enfermedad

RESUMEN

Squamous cell carcinoma (SCC) represents 20% of cases of non-melanoma skin cancer, and the most common treatment is the removal of the tumor, which can leave large scars. 5-Fluorouracil (5FU) is a drug used in the treatment of SCC, but it is highly hydrophilic, resulting in poor skin penetration in topical treatment. Some strategies can be used to increase the cutaneous penetration of the drug, such as the combination of liposomes containing penetration enhancers, for instance, surfactants, associated with the use of microneedling. Thus, the present work addresses the development of liposomes with penetration enhancers, such as sorbtitan monolaurate, span 20, for topical application of 5-FU and associated or not with the use of microneedling for skin delivery. Liposomes were developed using the lipid film hydration, resulting in particle size, polydispersity index, zeta potential, and 5-FU encapsulation efficiency of 88.08 nm, 0.169, -12.3 mV, and 50.20%, respectively. The presence of span 20 in liposomes potentiated the in vitro release of 5-FU. MTT assay was employed for cytotoxicity evaluation and the IC50 values were 0.62, 30.52, and 24.65 µM for liposomes with and without span 20 and 5-FU solution, respectively after 72-h treatment. Flow cytometry and confocal microscopy analysis evidenced high cell uptake for the formulations. In skin penetration studies, a higher concentration of 5-FU was observed in the epidermis + dermis, corresponding to 1997.71, 1842.20, and 2585.49 ng/cm2 in the passive penetration and 3214.07, 2342.84, and 5018.05 ng/cm2 after pretreatment with microneedles, for solution, liposome without and with span 20, respectively. Therefore, herein, we developed a nanoformulation for 5-FU delivery, with suitable physicochemical characteristics, potent skin cancer cytotoxicity, and cellular uptake. Span 20-based liposomes increased the skin penetration of 5-FU in association of microneedling. Altogether, the results shown herein evidenced the potential of the liposome containing span 20 for topical delivery of 5-FU.

Asunto(s)

Fluorouracilo , Neoplasias Cutáneas , Hexosas , Humanos , Liposomas/metabolismo , Tamaño de la Partícula , Piel/metabolismo , Absorción Cutánea , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/metabolismo

RESUMEN

In this study, nanoemulsions of essential oil from Ocimumgratissimum (Linn) (EO) were produced using low and high energy techniques using cashew gum (CG) as a co-surfactant. The main constituents of the EO were determined by Gas Chromatography coupled with Mass Spectrometry (GC-MS), and their presence in the EO and in the formulations verified by Fourier Transform Infrared Spectroscopy (FTIR) and UV-visible spectrophotometry was observed the encapsulation efficiency (EE%), with colloidal stability. Nuclear magnetic resonance (NMR) was used to study cashew gum. Dynamic light scattering analysis (DLS) determined the nanoemulsion Z means, polydispersity index and the Zeta potential value, nanoparticle tracking analysis (NTA) were determined. The nanostructured EO showed better antibacterial action against the pathogenic gastroenteritis species Staphylococcus aureus, Escherichia coli and Salmonella enterica when compared to free EO. Atomic Force Microscopy (AFM) was used for morphological analysis of the nanoparticle and study of the action of the nanoemulsion through images of the cellular morphology of S. enterica. The antioxidant activity was evaluated against the ABTS radical (2,2'-azino-bis diazonium salt (3-ethylbenzothiazoline-6-sulfonic acid)). The encapsulation of EO in a nanostructured system improved its antibacterial and antioxidant activity, the low energy synthesis showed greater storage stability, remaining stable for 37 days.

Asunto(s)

Antibacterianos/química , Emulsiones/química , Ocimum/metabolismo , Aceites Volátiles/química , Gomas de Plantas/química , Hojas de la Planta/metabolismo

RESUMEN

Enoxaparin is an effective biological molecule for prevention and treatment of coagulation disorders. However, it is poorly absorbed in the gastrointestinal tract. In this study, we developed an Eudragit® L100 coated chitosan core shell nanoparticles for enoxaparin oral delivery (Eud/CS/Enox NPs) through a completely eco-friendly method without employing any high-energy homogenizer technique and any organic solvents. Spherical nanocarriers were successfully prepared with particle size lower than 300 nm, polydispersity index about 0.12 and zeta potential higher than +25 mV, entrapment efficiency greater than 95% and the in vitro release behavior confirms the good colloidal stability and the successful Eudragit® L100 coating process demonstrated by negligible cumulative enoxaparin release (<10%) when the particles are submitted to simulated gastric fluid conditions. Finally, we demonstrated that the core-shell structure of the particle influenced the drug release mechanism of the formulations, indicating the presence of the Eudragit® L100 on the surface of the particles. These results suggested that enteric-coating approach and drug delivery nanotechnology can be successfully explored as potential tools for oral delivery of enoxaparin.

Asunto(s)

Quitosano/química , Portadores de Fármacos/química , Enoxaparina/química , Nanopartículas/química , Liberación de Fármacos , Tamaño de la Partícula

RESUMEN

Industrial application of lycopene is limited due to its chemical instability and low bioavailability. This study proposes the development of fucan-coated acetylated cashew gum nanoparticles (NFGa) and acetylated cashew gum nanoparticles (NGa) for incorporation of the lycopene-rich extract from red guava (LEG). Size, polydispersity, zeta potential, nanoparticles concentration, encapsulation efficiency, transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to characterize nanoparticles. The antioxidant activity was determinated and cell viability was evaluated in the human breast cancer cells (MCF-7) and human keratinocytes (HaCaT) by MTT assay. The toxic effect was evaluated by hemolysis test and by Galleria mellonella model. NFGa showed higher stability than NGa, having a size of 162.10 ± 3.21 nm, polydispersity of 0.348 ± 0.019, zeta potential -30.70 ± 0.53 mV, concentration of 6.4 × 109 nanoparticles/mL and 60% LEG encapsulation. Microscopic analysis revealed a spherical and smooth shape of NFGa. NFGa showed antioxidant capacity by ABTS method and ORAC assay. The NFGa presented significant cytotoxicity against MCF-7 from the lowest concentration tested (6.25-200 µg/mL) and did not affect the cell viability of the HaCaT. NFGa showed non-toxic effect in the in vitro and in vivo models. Therefore, NFGa may have a promising application in LEG stabilization for antioxidant and antitumor purposes.

Asunto(s)

Anacardium/química , Antineoplásicos/administración & dosificación , Antioxidantes/administración & dosificación , Licopeno/administración & dosificación , Nanopartículas/química , Gomas de Plantas/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células HaCaT , Humanos , Licopeno/química , Licopeno/farmacología , Células MCF-7 , Polisacáridos/química , Psidium/química , Ovinos

RESUMEN

We developed a new hydrophobic polymer based on angico gum (AG), and we produced new nanoparticles to expand the applications of natural polysaccharides in nanomedicine. Phthalate angico gum (PAG) was characterized by 1H NMR, FTIR, elementary analysis, solubility, XRD, and TG. PAG was a hydrophobic and semi-crystalline material, a relevant characteristic for drug delivery system applications. As a proof of concept, nevirapine (NVP) was selected for nanoparticles development. Plackett-Burman's experimental design was used to understand the influence of several factors in nanoparticles production. PAG proved to be a versatile material for producing nanoparticles with different characteristics. Optimized nanoparticles were produced using desirability parameters. NVP-loaded PAG nanoparticles formulation showed 202.1 nm of particle size, 0.23 of PDI, -17.1 of zeta potential, 69.8 of encapsulation efficiency, and promoted modified drug release for 8 h. Here we show that PAG presents as a promising biopolymer for drug delivery systems.

Asunto(s)

Tecnología Química Verde , Nanopartículas/química , Nanotecnología , Ácidos Ftálicos/química , Gomas de Plantas/química , Liberación de Fármacos , Humanos , Microscopía de Fuerza Atómica , Peso Molecular , Nevirapina/farmacología , Tamaño de la Partícula , Espectroscopía de Protones por Resonancia Magnética , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X

RESUMEN

This research reports, for the first time, the immobilization of an enzyme - Rhus vernificera laccase - on cashew gum (CG) nanoparticles (NPs) and its application as a biological layer in the design and development of an electrochemical biosensor. Laccase-CG nanoparticles (LacCG-NPs) were prepared by the nanoprecipitation method and characterized by UV-Vis spectrophotometry, atomic force microscopy, scanning electron microscopy, attenuated total reflectance-Fourier-transform infrared spectroscopy, circular dichroism, cyclic voltammetry, and electrochemical impedance spectroscopy. The average size and stability of the NPs were predicted by DLS and zeta potential. The ATR-FTIR results clearly demonstrated an interaction between -NH and -OH groups to form LacCG-NPs. The average size found for LacCG-NPs was 280 ± 53 nm and a polydispersity index of 0.309 ± 0.08 indicated a good particle size distribution. The zeta potential shows a good colloidal stability. The use of a natural product to prepare the enzymatic nanoparticles, its easy synthesis and the immobilization efficiency should be highlighted. LacCG-NPs were successfully applied as a biolayer in the development of an amperometric biosensor for catechol detection. The resulting device showed a low response time (6 s), good sensitivity (7.86 µA µM-1 cm-2), wide linear range of 2.5 × 10-7-2.0 × 10-4 M, and low detection limit (50 nM).

Asunto(s)

Materiales Biocompatibles/química , Técnicas Biosensibles , Catecoles/análisis , Lacasa/química , Nanopartículas/química , Gomas de Plantas/química , Anacardium/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/metabolismo , Conformación de Carbohidratos , Técnicas Electroquímicas , Lacasa/metabolismo , Ensayo de Materiales , Modelos Moleculares , Nanopartículas/metabolismo , Tamaño de la Partícula , Gomas de Plantas/aislamiento & purificación , Gomas de Plantas/metabolismo , Toxicodendron/enzimología

RESUMEN

In the present work, we investigated the minimal inhibitory concentration (MIC) against fungal strains (Fonsecaea pedrosoi, Microsporum canis, Candida albicans, Cryptococcus neoformans), and cytotoxicity to normal cell lines for modified red angico gum (AG) with eterifying agent N-chloride (3-chloro-2-hydroxypropyl) trimethylammonium (CHPTAC). Quaternized ammonium groups were linked to AG backbone using N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride. The chemical features of the quaternized gum derivatives (QAG) were analyzed by: FTIR, elemental analysis, Zeta potential and gel permeation chromatography. The angico quaternizated gum presented a degree of substitution (DS) of 0.22 and Zeta potential of +36.43. For the antifungal test, it was observed that unmodified gum did not inhibit fungal growth. While, QAG inhibited the growth of most fungi used in this study. By AFM technique QAG interacted with the fungal surface, altering wall roughness significantly. The probable affinity of fragments of the QAG structure for the fungal enzyme 5I33 (Adenylosuccinate synthetase) has been shown by molecular docking. Low cytotoxicity was observed for polymers (unmodified gum and QAG). The results demonstrate that the quaternized polymer of AG presented in this study is a quite promising biomaterial for biotechnological applications.

Asunto(s)

Antifúngicos , Citotoxinas , Inhibidores Enzimáticos , Fabaceae/química , Proteínas Fúngicas , Hongos/enzimología , Simulación del Acoplamiento Molecular , Polisacáridos , Animales , Antifúngicos/química , Antifúngicos/farmacología , Citotoxinas/química , Citotoxinas/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/química , Células HEK293 , Humanos , Ligasas/antagonistas & inhibidores , Ligasas/química , Ratones , Polisacáridos/química , Polisacáridos/farmacología

RESUMEN

This study presents a green synthesis route to silver nanoparticles (AgNPs) stabilized with cashew gum (CG) or carboxymethylated cashew gum (CCG) using microwave-assisted synthesis and evaluates their antibacterial activity. The antimicrobial activity was measured by determining the minimum inhibitory concentration (MIC) with Staphylococcus aureus and Escherichia coli. In both cases of the presence of CG and CCG, it was found that higher pH lead to more efficient conversion of silver nitrate to AgNPs with well dispersed, spherical and stable particles as well as low crystallinity. CCG-capped AgNPs were slightly smaller (137.0 and 96.3 nm) than those coated with non-modified gum (144.7 and 100.9 nm). The samples presented promising antibacterial activity, especially on Gram-negative bacteria, resulting in significant membrane damage on treated bacteria in comparison to the untreated control, observed by atomic force microscopy. Thus, a quick and efficient synthesis route was applied to produce CGAgNPs and CCGAgNPs with antimicrobial potential.

Asunto(s)

Anacardium , Antibacterianos , Nanopartículas del Metal , Gomas de Plantas , Plata , Antibacterianos/administración & dosificación , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Microondas , Gomas de Plantas/administración & dosificación , Gomas de Plantas/química , Plata/administración & dosificación , Plata/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo

RESUMEN

This paper explores the application of cashew gum (CG) as an in vitro antiproliferative, firstly by isolating and characterizing the gum using elemental analysis, gel-permeation chromatography, nuclear magnetic resonance (NMR) and atomic force microscopy (AFM). The molar mass of isolated CG was in the order of 103-104 g/mol, with small protein traces present. Polymer characterization by NMR identified key signals correlating to galactose, glucose, rhamnose and acid-related groups. Three distinct conformational stages were observed by AFM. The impact of CG on cell morphology and viability with both tumor and non-tumor cell lines was studied by AFM and 3-(4,5-dimethyl-2-thiazole)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay respectively. Antiproliferative activity was confirmed for HCT116 (colorectal carcinoma), B16F10 (melanoma) and HL60 (promyelocytic leukemia) cancer cell lines. A change in cell morphology was demonstrated as an increased surface roughness for HL60. Considering that a CG does not exhibit cytotoxicity to non-tumor lines, it can be seen that the CG shows selectivity for tumor cells and can be a promising biomaterial for future studies.

Asunto(s)

Anacardium/química , Microscopía de Fuerza Atómica , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Materiales Biocompatibles/química , Línea Celular Tumoral , Humanos , Espectroscopía de Resonancia Magnética , Gomas de Plantas/química

RESUMEN

This work was aimed at the production and characterization of a new nanocarrier based on a Sterculia striata polysaccharide (SSP) modified via acylation reaction with propionic anhydride. Nanocapsules of propionated SSP (PSSP) were produced via spontaneous nanoemulsification process and tested as a potential amphotericin B (AMB) nanocarrier. Stable nanoparticles with a very low polydispersity index (0.08-0.29) and high zeta potential (ζ -42.7 to -53.8 mV) were obtained. Particle size was dependent on the degree of substitution and ranged from 205 to 286 nm. A nanocapsule with a degree of substitution (DS) of 2.53 (NCP 2.53) was selected for encapsulation, biocompatibility, and antifungal evaluation against Candida albicans strains. A maximum of 98.3% AMB encapsulation was achieved. Encapsulated AMB was in its monomeric form and showed good biocompatibility and antifungal activity against four C. albicans strains. Data indicate that PSSP has potential as a nanocarrier system for AMB.

Asunto(s)

Anfotericina B/farmacología , Portadores de Fármacos/química , Nanopartículas/química , Polisacáridos/química , Propionatos/química , Sterculia/química , Antifúngicos/farmacología , Materiales Biocompatibles/química , Candida albicans/efectos de los fármacos , Liberación de Fármacos , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nanocápsulas/química , Tamaño de la Partícula , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier

RESUMEN

In synthesis of silver nanoparticles (AgNPs), the composition of the stabilizer used can be closely related to the effectiveness of the synthesis and to the shape of the final nanoparticles. Recently, the use of collagen as an effective nanoparticle stabilization agent was reported. In this work, synthesis of silver nanoparticles using mixed capping agents is reported. The capping agents used were cashew gum-hydrolyzed collagen; kappa carrageenan-hydrolyzed collagen, and agar-hydrolyzed collagen. We evaluated antibacterial action against Gram-positive and Gram-negative bacteria, as well as antifungal activity and cytotoxicity. Homogenized mixtures of collagen and aqueous cashew gum, carrageenan or agar respectively were used to produce the nanoparticles AgNPcolCashew, AgNPcolCarr and AgNPcolAgar. AgNP characterization was performed using Uv-vis, XRD, TEM and DLS and the biological activities were assayed using MIC and MBC analyses for both antibacterial and antifungal application. Results showed that the AgNPcollcar sample showed the strongest bacterial inhibition with MIC values of 62.5 and 31.25 µM/mL Ag against E. coli and P. aeruginosa respectively. Interestingly, AgNPcollAgar also presented the lowest cytotoxicity when compared with other AgNPs and AgNO3.

Asunto(s)

Colágeno/química , Nanopartículas del Metal/química , Polímeros/química , Plata/química , Plata/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/toxicidad , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Antifúngicos/toxicidad , Candida albicans/efectos de los fármacos , Técnicas de Química Sintética , Escherichia coli/efectos de los fármacos , Hemólisis/efectos de los fármacos , Hidrólisis , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Nanotecnología , Pseudomonas aeruginosa/efectos de los fármacos , Ovinos , Plata/toxicidad

RESUMEN

Intestinal mucositis is a common complication associated with 5-fluorouracil (5-FU), a chemotherapeutic agent used for cancer treatment. Cashew gum (CG) has been reported as a potent anti-inflammatory agent. In the present study, we aimed to evaluate the effect of CG extracted from the exudate of Anacardium occidentale L. on experimental intestinal mucositis induced by 5-FU. Swiss mice were randomly divided into seven groups: Saline, 5-FU, CG 30, CG 60, CG 90, Celecoxib (CLX), and CLX + CG 90 groups. The weight of mice was measured daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis), levels of malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH), and immunohistochemical analysis of interleukin 1 beta (IL-1ß) and cyclooxygenase-2 (COX-2). 5-FU induced intense weight loss and reduction in villus height compared to the saline group. CG 90 prevented 5-FU-induced histopathological changes and decreased oxidative stress through decrease of MDA levels and increase of GSH concentration. CG attenuated inflammatory process by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. Our findings suggest that CG at a concentration of 90 mg/kg reverses the effects of 5-FU-induced intestinal mucositis.

RESUMEN

Stable oil nanocapsules based on acetylated Sterculia striata polysaccharide (ASSP) were produced without the use of a surfactant, and derivatives of ASSP with four different degrees of substitution (DS) were synthesised. The data revealed that only derivatives with high DS were able to produce nanocapsules (NC), which exhibited monomodal size distribution profiles with a Z-average particle size, ζ-potential, and polydispersity index (PDI) that were dependent on ASSP DS and concentration. Nanocapsules were loaded with amphotericin B (AMB) with encapsulation efficiencies (EE%) that were dependent on drug and ASSP concentrations and DS. A maximum EE% value of 99.2% was achieved, and the loaded AMB was found to be in a monomeric form, even with a concentration one hundredfold higher than that usually observed for commercial AMB aqueous solutions. Loaded nanocapsules show an in vitro controlled release of AMB. As the monomeric AMB state decreased drug toxicity, ASSP nanocapsules loaded with AMB (NC1.68) have potential for use as a drug delivery system. AMB loaded NC 1.68 keeps its activity against 5 strains of Candida albicans tested.

Asunto(s)

Anfotericina B/administración & dosificación , Antifúngicos/administración & dosificación , Nanocápsulas/química , Polisacáridos/química , Sterculia/química , Acetilación , Materiales Biocompatibles , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Microscopía de Fuerza Atómica , Análisis Espectral

RESUMEN

The natural alkaloid epiisopiloturine has recently become the focus of study for various medicinal properties, particularly for its anti-inflammatory and antischistosomal effect. The incorporation of active molecules in natural polymeric matrices has garnered increasing interest during recent decades. A new derivative of cashew gum successfully obtained by gum acetylation has shown great potential as a carrier in controlled drug release systems. In this work, epiisopiloturine was encapsulated in acetylated cashew gum nanoparticles in order to increase solubility and allow slow release, whereas the morphology results were supported by computer simulations. The particles were produced under a variety of conditions, and thoroughly characterized using light scattering and microscopic techniques. The particles were spherical and highly stable in solution, and showed drug incorporation at high levels, up to 55% efficiency. Using a dialysis-based in vitro assay, these particles were shown to release the drug via a Fickian diffusion mechanism, leading to gradual drug release over approximately 6 h. These nanoparticles show potential for the use as drug delivery system, while studies on their potential anti-inflammatory action, as well as toxicity and efficacy assays would need to be performed in the future to confirm their suitability as drug delivery candidates.

Asunto(s)

4-Butirolactona/análogos & derivados , Alcaloides/química , Anacardium/química , Portadores de Fármacos/química , Imidazoles/química , Nanopartículas/química , Gomas de Plantas/química , 4-Butirolactona/química , Acetilación , Conformación de Carbohidratos , Liberación de Fármacos , Modelos Moleculares , Solubilidad