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1.
Mol Pharm ; 20(9): 4430-4442, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37579225

RESUMEN

Australasia is home to unique and endangered avian species. Drug administration to this group of animal patients for prophylaxis and treatment is challenging from a number of different perspectives. A key limitation for optimal drug dosing in birds is the lack of published pharmacokinetic studies to guide dose requirements. The aim of this review was to systematically investigate published literature on pharmacokinetics in penguin species and compare that with the pharmacokinetics of other avian species with a focus on two drugs: enrofloxacin and voriconazole. The review was conducted following PRISMA guidelines. A systematic literature search was performed in Pubmed, Embase, Scopus, and Web of Science databases. A key finding is that penguin pharmacokinetics differs from other avian species, with weight-adjusted AUC and Cmax values higher than most other avian species (e.g., for enrofloxacin, the AUC in the African penguin is 85.7 µg h/mL, which is more than double the other bird species). Doses for some avian species may be successfully extrapolated from other avian species; however, it appears important to consider factors other than just body weight (e.g., clearance mechanism and drug physicochemical characteristics). Consequently, there is an important need for robust pharmacokinetic data in wildlife species to ensure optimal therapy for this special group of patients. As part of this review, we identify key aspects that should be considered when estimating dose in species for which there is limited pharmacokinetic information available.


Asunto(s)
Spheniscidae , Animales , Voriconazol , Enrofloxacina
2.
J Am Pharm Assoc (2003) ; 63(3): 825-831, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36740527

RESUMEN

BACKGROUND: The importance of wildlife health has been critically emphasized by the current global pandemic. Pharmacists play a valuable role in the health care of companion animals and livestock; however, their involvement in exotic animal health is largely unexplored. OBJECTIVES: This project consulted with zoo vets in New Zealand and investigated their practices around prescribing and dispensing of medicines to explore the opportunities for the involvement of pharmacists. METHODS: A mixed methods approach was used where data were initially collected through an online survey distributed to 26 veterinarians and animal keepers working in zoos, wildlife parks, and sanctuaries. An optional semistructured interview followed the survey. RESULTS: The facilities surveyed housed New Zealand native animal species and 85% also housed exotic animals. Veterinarians dispensed 75% of medicines at their animal facility, whereas the remaining 25% were dispensed by veterinary nurses. On average, 5-10 medications were dispensed at each animal facility per day. Common medicines dispensed were antibiotics, pain relievers, and antifungals. Most respondents felt that they could benefit from working alongside pharmacists in veterinary care. Compounding, access to medicines and identification of tailored formulations were identified as areas where collaboration would be valued. Limitations in the knowledge of pharmacists in animal medicine were distinguished as an area enhancement to assist in collaborative relationships. CONCLUSIONS: There are opportunities for the skills of pharmacists to be incorporated into the care of animals in zoos and wildlife parks in New Zealand. Strengthening the pharmacist-veterinarian relationship can enhance the health outcomes of animals in animal facilities through this interprofessional interaction.


Asunto(s)
Animales Salvajes , Farmacéuticos , Animales , Humanos , Nueva Zelanda , Actitud del Personal de Salud , Encuestas y Cuestionarios
3.
Immunol Cell Biol ; 96(6): 656-665, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29499080

RESUMEN

Sustained-release vaccine delivery systems may enhance the immunogenicity of subunit vaccines and reduce the need for multiple vaccinations. The aim of this study was to develop a thermoresponsive hydrogel using poloxamer 407-chitosan (CP) grafted copolymer as a delivery system for single-shot sustained-release vaccines. The CP copolymer was synthesized using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide and N-hydroxysuccinimide chemistry. The CP copolymer was a free flowing solution at ambient temperature and transformed rapidly into a gel at body temperature. The hydrogels were loaded with vaccine antigen and adjuvants or the vaccine components were encapsulated in poly (lactic-co-glycolic acid) nanoparticles in order to ensure synchronous release. The CP hydrogels were stable for up to 18 days in vitro. Release of both nanoparticles and the individual components was complete, with release of the individual components being modulated by incorporation into nanoparticles. In vivo, a single dose of CP hydrogel vaccine induced strong, long lasting, cellular and humoral responses that could protect against the development of tumors in a murine melanoma model.


Asunto(s)
Adyuvantes Inmunológicos , Antígenos , Preparaciones de Acción Retardada , Hidrogeles , Vacunas , Adyuvantes Inmunológicos/administración & dosificación , Animales , Antígenos/administración & dosificación , Quitosano/síntesis química , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos , Hidrogeles/síntesis química , Hidrogeles/química , Melanoma Experimental , Ratones , Nanopartículas/química , Poloxámero/síntesis química , Temperatura , Vacunas/administración & dosificación , Vacunas/síntesis química , Vacunas/química
4.
J Liposome Res ; 28(4): 296-304, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28826286

RESUMEN

Allergic conditions affect more than a quarter of the population in developed countries, but currently available treatments focus more on symptom relief than treating the underlying atopic condition. α-Galactosylceramide (α-GalCer) is a potent immunomodulating compound that has been shown to have a regulatory effect when delivered systemically in nanoparticles. Parenteral delivery is not preferred for chronic conditions, such as allergy, and therefore, the aim of this study was to determine whether a regulatory response could be induced through oral administration in a model of atopy through incorporation of α-GalCer into stable particulate formulations (cationic liposomes, polymerized liposomes and poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs)). The formulations showed only minor changes in particle size, polydispersity index and retention of the model antigen ovalbumin (OVA) during incubation in simulated gastrointestinal (GI) conditions. Oral delivery of α-GalCer in cationic liposomes could induce immunostimulating effects systemically, as seen through increases in serum IgG antibody levels, whereas delivery of α-GalCer in polymerized liposomes and PLGA NPs induced local cytokine changes in the mesenteric lymph nodes (MLNs). The generated responses did not exhibit tolerogenic traits which could be useful for immunoregulation, but the responses generated varied between formulations and suggests that further characterization and optimization could lead to the desired immune response.


Asunto(s)
Portadores de Fármacos , Galactosilceramidas , Nanopartículas , Vacunas , Administración Oral , Animales , Composición de Medicamentos , Humanos , Hipersensibilidad/tratamiento farmacológico , Ratones Endogámicos C57BL , Vacunas/administración & dosificación , Vacunas/química
5.
J Dairy Sci ; 100(10): 7891-7896, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28822542

RESUMEN

The selection criteria of ideal probiotic bacteria are complex and involve many factors. One key criterion is based on the ability of the probiotic bacteria to adhere to the epithelial lining of the gastrointestinal tract. The objective of this study was to evaluate and compare the adherence and influence on membrane integrity of 2 selected lactobacilli isolates-Lactobacillus rhamnosus MI13 (dairy food origin) and L. plantarum RC2 (bovine rumen origin)-to Caco-2 cells in the presence and absence of Escherichia coli. The adhesion and influence on membrane integrity properties of the 2 Lactobacillus isolates were compared with Escherichia coli, a human commensal bacterium. From the adhesion studies, we concluded that the bovine rumen isolate exhibited better adherence to Caco-2 cells than the dairy food isolate. In contrast, the dairy food isolate better protected the Caco-2 monolayer from damage induced by ethanol.


Asunto(s)
Adhesión Bacteriana/fisiología , Membrana Celular/microbiología , Lacticaseibacillus rhamnosus/fisiología , Lactobacillus plantarum/fisiología , Probióticos/aislamiento & purificación , Animales , Células CACO-2 , Bovinos , Estructuras de la Membrana Celular , Escherichia coli/fisiología , Humanos , Rumen/microbiología
6.
Molecules ; 20(3): 4548-64, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25774489

RESUMEN

Antioxidants protect against damage from free radicals and are believed to slow the ageing process. Previously, we have reported the high antioxidant activity of 70% methanolic Sonchus oleraceus L. (Asteraceae) leaf extracts. We hypothesize that S. oleraceus extracts protect cells against H2O2-induced senescence by mediating oxidative stress. Premature senescence of young WI-38 cells was induced by application of H2O2. Cells were treated with S. oleraceus extracts before or after H2O2 stress. The senescence- associated ß-galactosidase (SA-ß-gal) activity was used to indicate cell senescence. S. oleraceus extracts showed higher cellular antioxidant activity than chlorogenic acid in WI-38 cells. S. oleraceus extracts suppressed H2O2 stress-induced premature senescence in a concentration-dependent manner. At 5 and 20 mg/mL, S. oleraceus extracts showed better or equivalent effects of reducing stress-induced premature senescence than the corresponding ascorbic acid treatments. These findings indicate the potential of S. oleraceus extracts to be formulated as an anti-ageing agent.


Asunto(s)
Antioxidantes/farmacología , Senescencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/efectos adversos , Extractos Vegetales/farmacología , Sonchus/química , Antioxidantes/química , Línea Celular , Ácido Clorogénico/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Extractos Vegetales/química , Hojas de la Planta/química , beta-Galactosidasa/metabolismo
7.
Carbohydr Polym ; 332: 121912, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38431415

RESUMEN

Bacterial-infected wounds present a significant challenge in the medical field, posing a severe threat to public health. Traditional wound dressings have limited efficacy in treating bacterial-infected wounds, and antibiotics suffer from cytotoxicity and drug resistance. Consequently, an urgent requirement exists for developing multifunctional wound dressings capable of providing superior antimicrobial activity and expediting wound repair. In recent years, chitosan-based natural polysaccharide hydrogels have garnered attention for their biocompatibility, antimicrobial properties, and ability to aid in hemostasis. This study presents the development of a multi-functional, bi-dynamic network hydrogel for the treatment of wounds infected with bacteria. The hydrogel consists of a backbone of chitosan grafted with chlorogenic acid (CA-ECS), oxidized pullulan polysaccharides (OP), and zinc ions (Zn2+). The CA-ECS/OP/Zn2+ hydrogel displayed strong adhesion, good injectability, and high mechanical strength and was biodegradable and biocompatible. Furthermore, adding Zn2+ and CA enhanced the hydrogel's mechanical properties and antioxidant and antimicrobial activities. In a rat model of full-thickness skin wounds infected with S. aureus, the CA-ECS/OP/Zn2+ hydrogel demonstrated great anti-inflammatory, angiogenic, and folliculogenic properties, resulting in accelerated wound healing. The CA-ECS/OP/Zn2+ hydrogel has great potential for treating bacterial-infected wounds.


Asunto(s)
Quitosano , Polifenoles , Animales , Ratas , Hidrogeles , Staphylococcus aureus , Polisacáridos/farmacología , Metales , Antibacterianos/farmacología
8.
Int J Pharm ; 628: 122284, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36244561

RESUMEN

Wildlife medicine is a specialised division of veterinary medicine that is concerned with patients that are physiologically very diverse with similarly diverse life histories. The medicines to be delivered to wildlife parallel those used in other areas of veterinary medicine and human medicine, however species-specific information on drug administration is lacking for wildlife species. Currently there are numerous threats of extinction to wildlife globally due to climate change and habitat destruction. The COVID-19 pandemic has also made us acutely aware of the important link between human health and wildlife health and how zoonotic diseases can cause devastating impacts globally. Consequently, the ability to effectively treat this group of animals with therapeutic compounds is becoming increasingly more critical. Importantly, delivery of therapeutics to wildlife is a particular challenge that must be overcome. The objective is to highlight the area of wildlife therapeutics as an emerging field by presenting case studies to illustrate the opportunities for engagement of pharmaceutical scientists in this fascinating frontier of research. The case studies included are avian malaria in yellow-eyed penguins, transmissible cancers in Tasmanian devils, and the vaccination of wildlife for the control of SARS-Cov-2 transmission.


Asunto(s)
Animales Salvajes , COVID-19 , Animales , Humanos , SARS-CoV-2 , Pandemias , Biofarmacia
9.
Colloids Surf B Biointerfaces ; 217: 112626, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35724599

RESUMEN

The interaction of nanoparticles with Caco-2 monolayers in cell culture underpins our predictions of the uptake of nanoformulations in vivo for drug delivery. Cell-penetrating peptides (CPP), such as oligoarginine, are currently of interest to enhance cellular uptake of bioactives and nanoparticles. This paper assesses the cellular association of poly(ethyl-cyanoacrylate) nanoparticles functionalized with di-arginine-histidine (RRH) in a Caco-2 cell model. We applied a computational model of particokinetics, In vitro Sedimentation, Diffusion and Dosimetry (ISDD) to predict the accumulation of nanoparticles on the cell surface. An important finding is that the proportion of nanoparticles associated with cells was less than 5 %. This has important implications for interpreting nanoparticle uptake in vitro. RRH-decoration does not appear to alter nanoparticle deposition, but increases association of nanoparticles with Caco-2 cells. Immediate deposition of nanoparticles on the cell surface was apparent and similar between formulations, but underestimated by the ISDD model. Key to understanding the nano-bio interface for drug delivery, nanoparticles that reach the cells were not necessarily absorbed by them, but can become detached. This variable of nanoparticle release from cells was incorporated into a new mathematical model presented here.


Asunto(s)
Péptidos de Penetración Celular , Nanopartículas , Células CACO-2 , Sistemas de Liberación de Medicamentos , Humanos , Polímeros
10.
Pharmaceutics ; 14(2)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35214080

RESUMEN

Nanoparticle drug delivery systems have emerged as a promising strategy for overcoming limitations of antimicrobial drugs such as stability, bioavailability, and insufficient exposure to the hard-to-reach bacterial drug targets. Although size is a vital colloidal feature of nanoparticles that governs biological interactions, the absence of well-defined size control technology has hampered the investigation of optimal nanoparticle size for targeting bacterial cells. Previously, we identified a lead antichlamydial compound JO146 against the high temperature requirement A (HtrA) protease, a promising antibacterial target involved in protein quality control and virulence. Here, we reveal that JO146 was active against Helicobacter pylori with a minimum bactericidal concentration of 18.8-75.2 µg/mL. Microfluidic technology using a design of experiments approach was utilized to formulate JO146-loaded poly(lactic-co-glycolic) acid nanoparticles and explore the effect of the nanoparticle size on drug delivery. JO146-loaded nanoparticles of three different sizes (90, 150, and 220 nm) were formulated with uniform particle size distribution and drug encapsulation efficiency of up to 25%. In in vitro microdilution inhibition assays, 90 nm nanoparticles improved the minimum bactericidal concentration of JO146 two-fold against H. pylori compared to the free drug alone, highlighting that controlled engineering of nanoparticle size is important in drug delivery optimization.

11.
Phytother Res ; 25(12): 1876-82, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21928279

RESUMEN

There is considerable interest in antioxidant dietary components that can be protective against degenerative diseases in humans. Puha (Sonchus oleraceus L.) is a rich source of polyphenols, and exhibits strong antioxidant activity as measured by the 2,2-diphenylpicrylhydrazyl (DPPH) assay. However, the potential of puha to protect against degenerative diseases requires that low molecular weight antioxidants (LMWA) are absorbed by, and active in, human cells. The cellular antioxidant activity (CAA) assay was used to investigate the antioxidant activity of puha leaf extracts. Preparation methods of freezing and freeze-drying reduced the total polyphenolic content compared with fresh puha, but did not affect the LMWA potential as determined by the DPPH assay. The IC(50) values were 0.012 ± 0.003 mg/mL and 0.010 ± 0.005 mg/mL for freeze-dried and fresh puha leaves, respectively. Using the CAA assay, it was shown that LMWAs from foliar extracts of puha were effectively absorbed into HepG2 cells, and exerted antioxidant activity at levels comparable to those of extracts from blueberry fruits, the much-touted antioxidant superfood. Methylene blue staining of HepG2 cells indicated that puha extracts were not cytotoxic at concentrations below 100 mg DW/mL. The data indicate the potential of puha as a nutraceutical supplement for human health.


Asunto(s)
Antioxidantes/análisis , Extractos Vegetales/análisis , Polifenoles/análisis , Sonchus/química , Antioxidantes/química , Liofilización , Células Hep G2 , Humanos , Extractos Vegetales/química , Hojas de la Planta/química , Polifenoles/química
12.
ACS Appl Bio Mater ; 4(4): 3155-3165, 2021 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35014403

RESUMEN

Cell-penetrating peptides (CPPs) are known to interact with cell membranes and by doing so enhance cellular interaction and subsequent cellular internalization of nanoparticles. Yet, the early events of membrane interactions are still not elucidated, which is the aim of the present work. Surface conjugation of polymeric nanoparticles with cationic CPPs of different architecture (short, long linear, and branched) influences the surface properties, especially the charge of the nanoparticles, and therefore provides the possibility of increased electrostatic interactions between nanoparticles with the cell membrane. In this study, the physicochemical properties of CPP-tagged poly(lactic-co-glycolic acid) (PLGA) nanoparticles were characterized, and nanoparticle-cell interactions were investigated in HeLa cells. With the commonly applied methods of flow cytometry as well as confocal laser scanning microscopy, low and similar levels of nanoparticle association were detected for the PLGA and CPP-tagged PLGA nanoparticles with the cell membrane. However, single particle tracking of CPP-tagged PLGA nanoparticles allowed direct observation of the interactions of individual nanoparticles with cells and consequently elucidated the impact that the CPP architecture on the nanoparticle surface can have. Interestingly, the results revealed that nanoparticles with the branched CPP architecture on the surface displayed decreased diffusion modes likely due to increased interactions with the cell membrane when compared to the other nanoparticles investigated. It is anticipated that single particle approaches like the one used here can be widely employed to reveal currently unresolved characteristics of nanoparticle-cell interaction and aid in the design of improved surface-modified nanoparticles for efficient delivery of therapeutics.


Asunto(s)
Materiales Biocompatibles/química , Péptidos de Penetración Celular/química , Nanopartículas/química , Ácido Poliglicólico/química , Células HeLa , Humanos , Ensayo de Materiales , Tamaño de la Partícula
13.
Carbohydr Polym ; 263: 117998, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33858583

RESUMEN

Herein, dual-bioresponsive of Rhein (RH) in promoting colonic mucous damage repair and controlling inflammatory reactions were combined by the dual-targeting (intestinal epithelial cells and macrophages) oral nano delivery strategy for effective therapy of ulcerative colitis (UC). Briefly, two carbohydrates, calcium pectinate (CP) and hyaluronic acid (HA) were used to modify lactoferrin (LF) nanoparticles (NPs) to encapsulate RH (CP/HA/RH-NPs). CP layer make CP/HA/RH-NPs more stable and protect against the destructive effects of the gastrointestinal environment and then release HA/RH-NPs to colon lesion site. Cellular uptake evaluation confirmed that NPs could specifically target and enhance the uptake rate via LF and HA ligands. in vivo experiments revealed that CP/HA/RH-NPs significantly alleviated inflammation by inhibiting the TLR4/MyD88/NF-κB signaling pathway and accelerated colonic healing. Importantly, with the help of CP, this study was the first to attempt for LF as a targeting nanomaterial in UC treatment and offers a promising food-based nanodrug in anti-UC.


Asunto(s)
Antraquinonas/farmacología , Colitis Ulcerosa/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Ácido Hialurónico/química , Lactoferrina/química , Nanopartículas/química , Pectinas/química , Animales , Antraquinonas/química , Transporte Biológico , Línea Celular , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Portadores de Fármacos/uso terapéutico , Liberación de Fármacos , Inhibidores Enzimáticos/química , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Humanos , Receptores de Hialuranos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , FN-kappa B/antagonistas & inhibidores , Nanopartículas/uso terapéutico , Receptores de Superficie Celular/metabolismo , Proteínas de Uniones Estrechas/metabolismo , Distribución Tisular , Receptor Toll-Like 4/antagonistas & inhibidores
14.
Biomed Chromatogr ; 24(2): 132-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19517451

RESUMEN

A high-performance liquid chromatography (HPLC) method for assay of d-Lys(6)-GnRH contained in a microemulsion-type formulation is described. The peptide is extracted from the microemulsion matrix and quantified using a two-step gradient method. Separation from microemulsion compounds and potential peptide oxidation products was achieved on a Jupiter C(18) column at 40 degrees C, using a gradient of 10-35% CH(3)CN for peptide elution. The correlation of peak intensity measured at 220 nm and peptide concentration was linear over the range 2.5-60 microg/mL with a correlation coefficient of 0.9997 and a y-intercept not significantly different from zero (p > 0.05). Intraday and interday variability of the assay was less than 5% for multiple injections of samples containing 7.5, 30 and 60 microg/mL. The lower limit of quantitation was calculated to be 0.38 microg/mL, and the lower limit of detection was 0.13 microg/mL. The assay was applied to samples that were stressed under physiological conditions (37 degrees C, pH 7.4) over 4 days. Three degradation peaks were well resolved from the parent peptide, demonstrating the selectivity of the assay. Off-line MALDI TOF mass spectrometry was applied to identify these degradation species as oxidation products of the peptide.


Asunto(s)
Hormona Liberadora de Gonadotropina/análogos & derivados , Péptidos/química , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Emulsiones , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análisis , Indicadores y Reactivos , Modelos Lineales , Oxidación-Reducción , Fragmentos de Péptidos/análisis , Reproducibilidad de los Resultados , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
J Control Release ; 327: 444-455, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-32853729

RESUMEN

In this work, we sought to incorporate coenzyme Q10-loaded nanoemulsions into a food system and to understand the impact of food digestion on the in vivo bioavailability of this bioactive compound. We selected octenyl succinic anhydride modified starch as emulsifier to prepare the nanoemulsions (with approximately 200 nm droplet diameter) after comparing with two other food-grade surfactants (whey protein isolate and lecithin) in terms of their colloidal stability during simulated gastrointestinal digestion. The change in ζ-potential revealed that the initial emulsifier might be partially replaced by bile salts under intestinal conditions, and the mixed micelles formed after digestion showed an apparent permeability coefficient of 4.79 × 10-6 cm/s in a rat intestinal epithelial cell line, without compromising the trans-epithelial electrical resistance. In a second step, a high protein beverage that incorporated the coenzyme Q10-loaded nanoemulsion was developed in a food pilot plant. The beverage had a particle size of D4,3 = 18 µm and D3,2 = 2.5 µm, corresponding to its different components. The changes in particle morphology and size distribution were analysed to understand the behaviour of this beverage during simulated gastrointestinal digestion. When coenzyme Q10 was encapsulated into the nanoemulsions and the beverage, its bioavailability in vivo increased 1.8- and 2.8-fold respectively, compared with coenzyme Q10 dissolved in oil. The higher coenzyme Q10 bioavailability in the beverage was probably because of a significantly higher level of lipolytic activity found for beverage than for nanoemulsions during gastrointestinal digestion. These results show the potential of using natural food materials to generate formulations to improve the bioavailability of bioactive compounds. More importantly, we highlight the influence of food digestion (i.e. lipolysis) on the absorption of hydrophobic bioactive components and suggest that food systems can be utilised as a dosage form to further enhance oral bioavailability.


Asunto(s)
Tracto Gastrointestinal , Animales , Disponibilidad Biológica , Emulsiones/metabolismo , Tracto Gastrointestinal/metabolismo , Tamaño de la Partícula , Ratas , Ubiquinona/análogos & derivados
16.
Pharmaceutics ; 12(12)2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33322287

RESUMEN

Antioxidant supplementation may potentially be beneficial for embryonic development to reduce complications associated with increased levels of oxidative stress. Chlorogenic acid, one of the key polyphenolic antioxidants in S. oleraceus, was evaluated for potential protective effects during embryonic development of zebrafish exposed to the teratogen auranofin. Zebrafish embryos were transiently exposed to auranofin to induce developmental abnormalities. Phenotypic abnormalities were scored based on their severity at day 5 post-fertilization. The embryos supplemented with 250 µM chlorogenic acid showed a significantly lower score in phenotypic abnormalities compared to non-supplemented embryos after auranofin exposure. Therefore, supplementation with a low dose of chlorogenic acid showed a protective effect from auranofin-induced deformities and encouraged normal growth in zebrafish embryos. This study provides further support for the potential of using antioxidant supplementation during embryonic development for protection against malformation.

17.
Biomed Chromatogr ; 23(11): 1169-74, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19444802

RESUMEN

Selenomethionine (SeMet) is a widely used nutritional supplement that has potential benefit for people living in selenium-deficient areas. Previous research has shown that selenium administered as SeMet undergoes significant enterohepatic recycling which may involve the gut microflora. In order to investigate this we have developed a simple method for the quantitation of l-SeMet in rat gut content suspensions prepared from jejunum, ileum, caecum and colon. After incubation of l-SeMet with gut content suspensions, samples were deproteinized with sulfosalicylic acid and derivatized with o-phthaldialdehyde (OPA) and N-acetyl-l-cysteine (NAC). Mass spectrometry confirmed the formation of a 1:1:1 derivative of l-SeMet with OPA and NAC. Samples were analysed by reversed-phase high-performance liquid chromatography with fluorescence detection. The assay was linear in the concentration range 0.5-100 microg/mL (r(2) = 0.9992) with a limit of detection of 0.025 microg/mL (signal-to-noise ratio of 5). Intra-day and inter-day accuracies were 91.1-92.8 and 91.7-95.5%, respectively with corresponding precisions as relative standard deviation of <5%. Incubation of l-SeMet with gut content suspensions from different parts of the rat intestine showed that l-SeMet metabolism occurs mainly in the caecum.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Contenido Digestivo/química , Selenometionina/metabolismo , Acetilcisteína/química , Animales , Bencenosulfonatos , Masculino , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Salicilatos/química , Selenometionina/análisis , Sensibilidad y Especificidad , o-Ftalaldehído/química
18.
Pharm Nanotechnol ; 7(6): 423-443, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31629401

RESUMEN

BACKGROUND: Microfluidics is becoming increasingly of interest as a superior technique for the synthesis of nanoparticles, particularly for their use in nanomedicine. In microfluidics, small volumes of liquid reagents are rapidly mixed in a microchannel in a highly controlled manner to form nanoparticles with tunable and reproducible structure that can be tailored for drug delivery. Both polymer and lipid-based nanoparticles are utilized in nanomedicine and both are amenable to preparation by microfluidic approaches. AIM: Therefore, the purpose of this review is to collect the current state of knowledge on the microfluidic preparation of polymeric and lipid nanoparticles for pharmaceutical applications, including descriptions of the main synthesis modalities. Of special interest are the mechanisms involved in nanoparticle formation and the options for surface functionalisation to enhance cellular interactions. CONCLUSION: The review will conclude with the identification of key considerations for the production of polymeric and lipid nanoparticles using microfluidic approaches.


Asunto(s)
Lípidos/síntesis química , Técnicas Analíticas Microfluídicas/instrumentación , Polímeros/síntesis química , Sistemas de Liberación de Medicamentos , Humanos , Lípidos/química , Técnicas Analíticas Microfluídicas/métodos , Nanomedicina , Nanopartículas/química , Polímeros/química
19.
Int J Pharm X ; 1: 100030, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31517295

RESUMEN

The efficient and reproducible production of nanoparticles using bulk nanoprecipitation methods is still challenging because of low batch to batch reproducibility. Here, we optimize a bulk nanoprecipitation method using design of experiments and translate to a microfluidic device to formulate surface-modified poly-lactic-co-glycolic (PLGA) nanoparticles. Cell-penetrating peptides (CPPs) with a short, long linear or branched architecture were used for the surface modification of PLGA nanoparticles. The microfluidics method was more time efficient than the bulk nanoprecipitation method and allowed the formulation of uniform PLGA nanoparticles with a size of 150 nm, a polydispersity index below 0.150 and with better reproducibility in comparison to the bulk nanoprecipitation method. After surface modification the size of CPP-tagged PLGA nanoparticles increased to 160-180 nm and the surface charge of the CPP-tagged PLGA nanoparticles varied between -24 mV and +3 mV, depending on the architecture and concentration of the conjugated CPP. Covalent attachment of CPPs to the PLGA polymer was confirmed with FTIR by identifying the formation of an amide bond. The conjugation efficiency of CPPs to the polymeric PLGA nanoparticles was between 32 and 80%. The development and design of reproducible nanoformulations with tuneable surface properties is crucial to understand interactions at the nano-bio interface.

20.
Pharm Nanotechnol ; 7(6): 469-483, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31648653

RESUMEN

OBJECTIVE: To compare the characteristics of rutin-loaded PLGA (poly(lactic-coglycolic acid)) nanoparticles prepared using a single emulsion evaporation method (bulk method) and a nanoprecipitation method using microfluidics. METHODS: Rutin-loaded PLGA nanoparticles were produced using different methods and characterized for size, zeta potential, entrapment efficiency (EE) and drug loading (DL). A design of experiments approach was used to identify the effect of method parameters to optimize the formulation. DSC was used to investigate the solid-state characteristics of rutin and PLGA and identify any interactions in the rutin-loaded PLGA nanoparticles. The release of rutin from PLGA nanoparticles was examined in biorelevant media and phosphate buffer (PBS). RESULTS: The optimal formulation of rutin-loaded PLGA nanoparticles produced using a microfluidics method resulted in a higher entrapment efficiency of 34 ± 2% and a smaller size of 123 ± 4 nm compared to a bulk method (EE 27 ± 1%, size 179 ± 13 nm). The solidstate of rutin and PLGA changed from crystalline to amorphous with the preparation of rutin- loaded PLGA nanoparticles. More importantly, using microfluidics, rutin released faster from rutin-loaded PLGA nanoparticles in biorelevant media and PBS with higher burst release compared to the rutin release from the nanoparticles prepared by using the bulk method. CONCLUSION: Rutin can be encapsulated in nanoparticles formulated with different methods with mean sizes of less than 200 nm. Microfluidics produced more uniform rutin-loaded PLGA nanoparticles with a higher EE, DL and faster release compared to a bulk production method.


Asunto(s)
Antioxidantes/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Rutina/química , Precipitación Química , Emulsiones , Técnicas Analíticas Microfluídicas , Nanopartículas , Tamaño de la Partícula
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