RESUMEN
Nanotechnology has played a prominent role in biomedical engineering, offering innovative approaches to numerous treatments. Notable advances have been observed in the development of medical devices, contributing to the advancement of modern medicine. This article briefly discusses key applications of nanotechnology in tissue engineering, controlled drug release systems, biosensors and monitoring, and imaging and diagnosis. The particular emphasis on this theme will result in a better understanding, selection, and technical approach to nanomaterials for biomedical purposes, including biological risks, security, and biocompatibility criteria.
Asunto(s)
Sistemas de Liberación de Medicamentos , Nanoestructuras , Sistemas de Liberación de Medicamentos/métodos , Nanotecnología/métodos , Ingeniería Biomédica/métodos , Ingeniería de Tejidos/métodosRESUMEN
The plant popularly known as "negramina" (Siparuna guianensis Aubl.), member of the family Siparunaceae produces an essential oil that presents several biological activities reported in literature. Here, the essential oil was obtained by hydrodistillation from fresh leaves collected in the state of Roraima, far north of the Amazon. Chemical composition of the essential oil was characterized by gas chromatography coupled to mass spectrometry (GC-MS) and flame ionization detector (GC-FID). The sesquiterpenoid shyobunone and its derivatives were identified as major compounds in the oil (>40%). The effect of S. guianensis essential oil on the acetylcholinesterase (AChE) activity from Crassostrea rhizophorae, Litopenaeus vannamei and Electrophorus electricus was tested by spectrophotometric assays. The essential oil has been identified as an AChE inhibitor. The mechanism of inhibition was investigated as well as spectrofluorimetric interactions between the essential oil and the enzyme. 1H NMR titration and molecular docking were also investigated. The spectrophotometric results revealed that shyobunone and its derivatives strongly interact with AChE with a kind of non-competitive inhibition. Interaction studies support the results of enzyme inhibition. Molecular coupling predicted that iso-shyobunone is the strongest ligand, corroborated by fluorescence suppression and 1H NMR titration results. In conclusion, Siparuna guianensis essential oil can be a new source of shyobunone and derivatives capable to reversibly inhibit AChE showing potential neuroprotective properties to be applied in the treatment of Alzheimer's disease.
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Aceites Volátiles , Sesquiterpenos , Cromatografía de Gases y Espectrometría de Masas , Simulación del Acoplamiento Molecular , Aceites Volátiles/farmacología , Hojas de la Planta , Sesquiterpenos/farmacologíaRESUMEN
Mosquito-borne arboviruses compromise human health worldwide. Due to resistance to chemical insecticides, natural compounds have been studied to combat mosquitoes. Previous works have demonstrated a larvicidal activity of the water-soluble Moringa oleifera lectin (WSMoL) against Aedes aegypti, suggesting a mechanism of action based on the interaction between lectin and chitin present in the larvae's peritrophic matrix. In this work, it was investigated the WSMoL activity against Aedes aegypti larvae, by using luminescent bioconjugates of WSMoL conjugated to l-glutathione capped CdTe quantum dots. The conjugation was confirmed by ITC experiments, presenting high enthalpy associated to hydrogen bond interactions between nanoparticles and lectins. The bioconjugate luminescence stability was evaluated by the quantum yield (QY) at different pHs, ionic strengths and heat treatment time. The best parameters reached were pH 7.0, absence of electrolytes and heat treatment, giving QYâ¯=â¯4.4 %. The larvae were exposed to the bioconjugates and analyzed by confocal and fluorescence microscopy. CdTe-WSMol were detected along the entire midgut tract, suggesting a strong interaction with peritrophic matrix and lumen of the Aedes aegypti.
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Compuestos de Cadmio/química , Glutatión/química , Larva/efectos de los fármacos , Lectinas/química , Moringa oleifera/química , Puntos Cuánticos/química , Telurio/química , Aedes/efectos de los fármacos , Animales , Biomarcadores/análisis , Calor , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Luminiscencia , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Puntos Cuánticos/ultraestructura , Difracción de Rayos XRESUMEN
Supramolecular interactions between ß-lapachone (ß-lap) and cyclodextrins (CDs) were investigated by isothermal titration calorimetry. The most favorable host: guest interaction was characterized using X-ray powder diffraction (XRD), differential scanning calorimetry and thermogravimetry (DSC/TG), spectroscopy (FT-IR), spectroscopy (2D ROESY) nuclear magnetic resonance (NMR), and molecular modeling. Phase solubility diagrams showed ß-, HP-ß-, SBE-ß-, γ-, and HP-γ-CDs at 1.5% (w/w) allowed an increase in apparent solubility of ß-lap with enhancement factors of 12.0, 10.1, 11.8, 2.4, and 2.2, respectively. ß-lap has a weak interaction with γ- and HP-γ-CDs and tends to interact more favorably with ß-CD and its derivatives, especially SBE-ß-CD (K = 4160 M-1 ; ΔG = -20.66 kJ·mol-1 ). Thermodynamic analysis suggests a hydrophobic interaction associated with the displacement of water from the cavity of the CD by the ß-lap. In addition, van der Waals forces and hydrogen bonds were responsible for the formation of complexes. Taken together, the results showed intermolecular interactions between ß-lap and SBE-ß-CD, thereby confirming the formation of the inclusion complex. Molecular docking results showed 2 main orientations in which the interaction of benzene moiety at the wider rim of the SBE-ß-CD is the most stable (average docking energy of -7.0 kcal/mol). In conclusion, ß-lap:SBE-ß-CD is proposed as an approach for use in drug delivery systems in cancer research.
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Calorimetría/métodos , Ciclodextrinas/química , Modelos Moleculares , Naftoquinonas/química , Rastreo Diferencial de Calorimetría , Entropía , Cinética , Simulación del Acoplamiento Molecular , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos XRESUMEN
Bullfrog oil (BO), a natural product obtained from recycling of adipose tissue from the amphibian Rana catesbeiana Shaw, has been recently evaluated as a therapeutic activity ingredient. This work aimed to evaluate the long-term and accelerated thermal oxidative stabilities of this product, which is a promising raw material for emulsion technology development. BO was extracted from amphibian adipose tissue at 70 °C with a yield of 60% ± 0.9%. Its main fatty acid compounds were oleic (30.0%) and eicosapentaenoic (17.6%) acids. Using titration techniques, BO showed peroxide, acid, iodine and saponification indices of 1.92 mEq·O2/kg, 2.95 mg·KOH/g oil, 104.2 g I2/100 g oil and 171.2 mg·KOH/g oil, respectively. In order to improve the accelerated oxidative stability of BO, synthetic antioxidants butylhydroxytoluene (BHT) and buthylhydroxyanisole (BHA) were used. The addition of BHT increased the oxidation induction time compared to the pure oil, or the oil containing BHA. From the results, the best oil-antioxidant mixture and concentration to increase the oxidative stability and allow the oil to be a stable raw material for formulation purposes was derived.
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Productos Biológicos/química , Aceites/química , Rana catesbeiana , Animales , Ácidos Grasos/química , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , TermodinámicaRESUMEN
Bullfrog oil is a natural product extracted from the Rana catesbeiana Shaw adipose tissue and used in folk medicine for the treatment of several diseases. The aim of this study was to evaluate the extraction process of bullfrog oil, to develop a suitable topical nanoemulsion and to evaluate its efficacy against melanoma cells. The oil samples were obtained by hot and organic solvent extraction processes and were characterized by titration techniques and gas chromatography mass spectrometry (GC-MS). The required hydrophile-lipophile balance and the pseudo-ternary phase diagram (PTPD) were assessed to determine the emulsification ability of the bullfrog oil. The anti-tumoral activity of the samples was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for normal fibroblast (3T3) and melanoma (B16F10) cell lines. Both extraction methods produced yielded around 60% and the oil was mainly composed of unsaturated compounds (around 60%). The bullfrog oil nanoemulsion obtained from PTPD presented a droplet size of about 390 nm and polydispersity = 0.05 and a zeta potential of about -25 mV. Both the bullfrog oil itself and its topical nanoemulsion did not show cytotoxicity in 3T3 linage. However, these systems showed growth inhibition in B16F10 cells. Finally, the bullfrog oil presented itself as a candidate for the development of pharmaceutical products free from cytotoxicity and effective for antineoplastic therapy.