RESUMEN
Cytosolic protein delivery remains elusive. The inability of most proteins to cross the cellular membrane is a huge hurdle. Here we explore the unique photothermal properties of gold nanorods (AuNRs) to trigger cytosolic delivery of proteins. Both partners, protein and AuNRs, are modified with a protease-resistant cell-penetrating peptide with nuclear targeting properties to induce internalization. Once internalized, spatiotemporal control of protein release is achieved by near-infrared laser irradiation in the safe second biological window. Importantly, catalytic amounts of AuNRs are sufficient to trigger cytosolic protein delivery. To the best of our knowledge, this is the first time that AuNRs with their maximum of absorption in the second biological window are used to deliver proteins into the intracellular space. This strategy represents a powerful tool for the cytosolic delivery of virtually any class of protein.
Asunto(s)
Nanopartículas del Metal , Nanotubos , Línea Celular Tumoral , Oro , FototerapiaRESUMEN
The ß-amyloid peptide (1-42) is a molecule capable of aggregating into neurotoxic structures that have been implicated as potential etiological factors of Alzheimer's Disease. The aim of this study was to evaluate the inhibition of ß-amyloid aggregation of ethyl acetate and ethanolic extracts obtained from Ugni molinae leaves on neurotoxic actions of ß-amyloid aggregates. Chemical analyses were carried out with the extracts in order to determine their phenolic profile and its quantification. Both extracts showed a tendency to reduce neuronal deaths caused by ß-amyloid. This tendency was inversely proportional to the evaluated concentrations. Moreover, the effect of EAE and ETE on ß-amyloid aggregation was studied by fluorimetric T Thioflavin assay and transmission electronic microscopy (TEM); the extracts showed a modulation in the aggregation process. Partly, it is believed that these effects can be attributed to the polyphenolic compounds present in the extracts.
Asunto(s)
Enfermedad de Alzheimer , Myrtaceae , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Humanos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fenoles/química , Extractos Vegetales/farmacología , Hojas de la Planta/químicaRESUMEN
The occurrence of the quercetin oxidation metabolite 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (BZF), whose antioxidant potency is notably higher than the antioxidant potency of quercetin, was investigated in twenty quercetin-rich plant foods. BZF was identified (HPLC-DAD-ESI-MS/MS) only in the dry outer scales of onions and shallots. Aqueous extracts of onions (OAE) and shallots (SAE) were evaluated for their antioxidant and cytoprotective properties. OAE, whose potency did not differ from SAE, protected ROS-exposed Caco2 cells against oxidative (78%) and cellular (90%) damage at a 3 µg/L concentration (corresponding to 0.03 nM of BZF). After chromatographic resolution of OAE, the BZF peak accounted fully and exclusively for its antioxidant effect. The antioxidant effects of OAE and of a pure BZF were described by two perfectly overlapping curves whose concentration-dependence was within the 3 × 10-4 to 102 nM BZF range. Such unprecedented low concentrations place BZF-containing plants on the frontier of the search for novel sources of antioxidants.
Asunto(s)
Antioxidantes/farmacología , Benzofuranos/análisis , Benzofuranos/farmacología , Cebollas/química , Quercetina/metabolismo , Antioxidantes/química , Benzofuranos/metabolismo , Células CACO-2 , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Frutas/química , Humanos , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sustancias Protectoras/química , Sustancias Protectoras/farmacología , Espectrometría de Masas en Tándem , Verduras/químicaRESUMEN
The most common type of dementia is Alzheimer's disease (AD), a progressive neurodegenerative disease characterized by impairment in cognitive performance in aged individuals. Currently, there is no effective pharmacological treatment that cures the disease due to the lack of knowledge on the actual mechanisms involved in its pathogenesis. In the last decades, the amyloidogenic hypothesis has been the most studied theory trying to explain the origin of AD, yet it does not address all the concerns relating to its development. In the present study, a possible new preclinical treatment of AD was evaluated using the ethyl acetate extract (EAE) of leaves of Ugni molinae Turcz. (synonym Myrtus ugni Molina Family Myrtacea). The effects were assessed on female transgenic mice from a preclinical model of familial AD (APPswe/PS1dE9) combined with a high fat diet. This preclinical model was selected due to the already available experimental and observational data proving the relationship between obesity, gender, metabolic stress, and cognitive dysfunction; related to characteristics of sporadic AD. According to chemical analyses, EAE would contain polyphenols such as tannins, flavonoid derivatives, and phenolic acids, as well as pentacyclic triterpenoids that exhibit neuroprotective, anti-inflammatory, and antioxidant effects. In addition, the treatment evidenced its capacity to prevent deterioration of memory capacity and reduction of progression speed of AD neuropathology.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Encéfalo/efectos de los fármacos , Memoria/efectos de los fármacos , Myrtus , Extractos Vegetales/uso terapéutico , Placa Amiloide/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Transgénicos , Extractos Vegetales/farmacología , Hojas de la Planta , Placa Amiloide/metabolismo , Placa Amiloide/patología , Presenilina-1/genética , Presenilina-1/metabolismoRESUMEN
The aim of this study was to determine the insecticide residue processing factor (PF) from plums to prunes and the effect of the industrial processing of prunes residue concentrations. Our results show an increase of insecticide concentrations during plum dehydration that is explained by fruit water loss; however, the normalized insecticide residue concentration, based on plum dry weights to compensate dehydration, was reduced. The water washing and tenderizing of prunes produced insecticide residue reductions of 22.9⯱â¯4.5% and 21.9⯱â¯4.2%, respectively. PF were: 1.157, 1.872, 1.316, 0.192, 2.198, 0.775 and 0.156 for buprofezin, l-cyhalothrin, spirodiclofen, indoxacarb, acetamiprid, imidacloprid and emamectin benzoate, respectively, being directly related to water solubility, aqueous hydrolysis and degradation point and inversely related to molecular mass and melting point. In plums for the dehydrated agroindustry the final product is prunes, therefore, it is crucial to consider the PF to determine the specific preharvest interval for this important agroindustry.
Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Residuos de Plaguicidas/análisis , Prunus domestica/química , Frutas/química , Frutas/metabolismo , Ivermectina/análogos & derivados , Ivermectina/análisis , Ivermectina/química , Ivermectina/aislamiento & purificación , Neonicotinoides/análisis , Neonicotinoides/química , Neonicotinoides/aislamiento & purificación , Nitrilos/análisis , Nitrilos/química , Nitrilos/aislamiento & purificación , Nitrocompuestos/análisis , Nitrocompuestos/química , Nitrocompuestos/aislamiento & purificación , Oxazinas/análisis , Oxazinas/química , Oxazinas/aislamiento & purificación , Oxidación-Reducción , Residuos de Plaguicidas/química , Residuos de Plaguicidas/aislamiento & purificación , Prunus domestica/metabolismo , Piretrinas/análisis , Piretrinas/química , Piretrinas/aislamiento & purificación , Extracción en Fase SólidaRESUMEN
Inorganic materials contain remarkable properties for drug delivery, such as a large surface area and nanoporous structure. Among these materials, CaCO3 microparticles (CMPs) exhibit a high encapsulation efficiency and solubility in acidic media. The extracellular pH of tumor neoplastic tissue is significantly lower than the extracellular pH of normal tissue facilitating the release of drug-encapsulating CMPs in this area. Conducting polyaniline (PANI) absorbs light energy and transforms it into localized heat to produce cell death. This work aimed to generate hybrid CMPs loaded with PANI for photothermal therapy (PTT). The hybrid nanomaterial was synthesized with CaCO3 and carboxymethyl cellulose in a simple, reproducible manner. The CMP-PANI-Cys particles were developed for the first time and represent a novel type of hybrid biomaterial. Resultant nanoparticles were characterized utilizing scanning electron microscopy, dynamic light scattering, zeta potential, UV-vis, FTIR and Raman spectroscopy. In vitro HeLa cells in dark and irradiated conditions showed that CMP-PANI-Cys and PANI-Cys are nontoxic at the assayed concentrations. Hybrid biomaterials displayed high efficiency for potential PTT compared with PANI-Cys. In summary, hierarchical hybrid biomaterials composed of CMPs and PANI-Cys combined with near infrared irradiation represents a useful alternative in PTT.
Asunto(s)
Compuestos de Anilina/química , Materiales Biocompatibles/farmacología , Carbonato de Calcio/química , Hipertermia Inducida/métodos , Nanopartículas/química , Fototerapia/métodos , Supervivencia Celular/efectos de los fármacos , Cisteína/química , Células HeLa , Humanos , Nanopartículas/ultraestructura , Tamaño de la Partícula , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad EstáticaRESUMEN
Gold nanoparticles (AuNPs) have been extensively used in biological applications because of their biocompatibility, size, and ease of characterization, as well as an extensive knowledge of their surface chemistry. These features make AuNPs readily exploitable for biomedical applications, including drug delivery and novel diagnostic and therapeutic approaches. In a previous work, we studied ex vivo distribution of the conjugate C(AuNP)-LPFFD for its potential uses in the treatment of Alzheimer's disease. In this study, we covalently labeled the conjugate with [(18)F]-fluorobenzoate to study the in vivo distribution of the AuNP by positron emission tomography (PET). After intravenous administration in rat, the highest concentration of the radiolabeled conjugate was found in the bladder and urine with a lower proportion in the intestine, demonstrating progressive accumulation compatible with biliary excretion of the conjugate. The conjugate also accumulated in the liver and spleen. PET imaging allowed us to study the in vivo biodistribution of the AuNPs in a noninvasive and sensitive way using a reduced number of animals. Our results show that AuNPs can be covalently and radioactively labeled for PET biodistribution studies.
Asunto(s)
Radioisótopos de Flúor/farmacocinética , Oro/química , Nanopartículas del Metal , Péptidos/farmacocinética , Animales , Cromatografía Líquida de Alta Presión , Evaluación Preclínica de Medicamentos , Masculino , Microscopía Electrónica de Transmisión , Péptidos/química , Tomografía de Emisión de Positrones , Ratas , Ratas Sprague-Dawley , Espectrofotometría Ultravioleta , Resonancia por Plasmón de Superficie , Distribución TisularRESUMEN
BACKGROUND: Arabidopsis thaliana copper metallochaperone CCH is a functional homologue of yeast antioxidant ATX1, involved in cytosolic copper transport. In higher plants, CCH has to be transported to specialised cells through plasmodesmata, being the only metallochaperone reported to date that leaves the cell where it is synthesised. CCH has two different domains, the N-terminal domain conserved among other copper-metallochaperones and a C-terminal domain absent in all the identified non-plant metallochaperones. The aim of the present study was the biochemical and biophysical characterisation of the C-terminal domain of the copper metallochaperone CCH. RESULTS: The conformational behaviour of the isolated C-domain in solution is complex and implies the adoption of mixed conformations in different environments. The ionic self-complementary peptide KTEAETKTEAKVDAKADVE, derived from the C-domain of CCH, adopts and extended conformation in solution with a high content in beta-sheet structure that induces a pH-dependent fibril formation. Freeze drying electron microscopy studies revealed the existence of well ordered amyloid-like fibrils in preparations from both the C-domain and its derivative peptide. CONCLUSION: A number of proteins related with copper homeostasis have a high tendency to form fibrils. The determinants for fibril formation, as well as the possible physiological role are not fully understood. Here we show that the plant exclusive C-domain of the copper metallochaperone CCH has conformational plasticity and forms fibrils at defined experimental conditions. The putative influence of these properties with plant copper delivery will be addressed in the future.