51 research outputs found

    The nasal delivery of nanoencapsulated statins – An approach for brain delivery

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    © 2016 Clementino et al. Purpose: Along with their cholesterol-lowering effect, statins have shown a wide range of pleiotropic effects potentially beneficial to neurodegenerative diseases. However, such effects are extremely elusive via the conventional oral administration. The purpose of the present study was to prepare and characterize the physicochemical properties and the in vivo biodistribution of simvastatin-loaded lecithin/chitosan nanoparticles (SVT-LCNs) suitable for nasal administration in view of an improved delivery of the statins to the brain. Materials and methods: Chitosan, lecithin, and different oil excipients were used to prepare nanocapsules loaded with simvastatin. Particle size distribution, surface charge, structure, simvastatin loading and release, and interaction with mucus of nanoparticles were determined. The nanoparticle nasal toxicity was evaluated in vitro using RPMI 2651 nasal cell lines. Finally, in vivo biodistribution was assessed by gamma scintigraphy via Tc99m labeling of the particles. Results: Among the different types of nanoparticles produced, the SVT-LCN_MaiLab showed the most ideal physicochemical characteristics, with small diameter (200 nm), positive surface charge (+48 mV) and high encapsulation efficiency (EE; 98%). Size distribution was further confirmed by nanoparticle tracking analysis and electron microscopy. The particles showed a relatively fast release of simvastatin in vitro (35.6%±4.2% in 6 hours) in simulated nasal fluid. Blank nanoparticles did not show cytotoxicity, evidencing that the formulation is safe for nasal administration, while cytotoxicity of simvastatin-loaded nanoparticles (IC50) was found to be three times lower than the drug solution (9.92 vs 3.50 μM). In rats, a significantly higher radioactivity was evidenced in the brain after nasal delivery of simvastatin-loaded nanoparticles in comparison to the administration of a similar dose of simvastatin suspension. Conclusion: The SVT-LCNs developed presented some of the most desirable characteristics for mucosal delivery, that is, small particle size, positive surface charge, long-term stability, high EE, and mucoadhesion. In addition, they displayed two exciting features: First was their biodegradability by enzymes present in the mucus layer, such as lysozyme. This indicates a new Trojan-horse strategy which may enhance drug release in the proximity of the nasal mucosa. Second was their ability to enhance the nose-to-brain transport as evidenced by preliminary gamma scintigraphy studies

    Evaluation the best condition of Fibrinolytic protease production using factorial design by Streptomyces sp DPUA 1573

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    XI Reunião Regional Nordeste da SBBq | 4th International Symposium in Biochemistry of Macromolecules and BiotechnologyFibrinolytic enzymes have the ability to degrade fibrin clots formed for avoiding intravascular thrombosis. In the pharmaceutical industry there is a search for new fibrinolytic agent that reduces the production cost and increasing productivity. The use of microorganism for enzyme production, such as the genus Streptomyces has been reported. Streptomyces is a Gram-positive bacteria, responsible for producing many bioactive compounds and extracellular enzymes of pharmaceutical interest. This study aimed to evaluated the production of fibrinolytic protease by Streptomyces sp DPUA 1573. Microbial cells were cultivated in the ISP2 for 48 hours, after this period the strains were inoculated in MS2 (soybean medium) that according with factorial design 24 (concentrations of soybean 0.5; 1.0 and 1.5%, glucose 0; 0.5 and 1.0% and different speeds 150 rpm; 200 rpm and 250 rpm and temperature 28C; 30C and 32C). The factorial design was analyzed by variance analysis (anova) and the glucose concentration showed a positive and significative effect. The results showed that the variable interaction had significant effect. that the best condition was composed 1.5% soybean, 1% glucose, 28 ºC and 150 speed in 48 hours, with production fibrinolytic 1391.66 U/mL. These values were higher than those reported in the literature. However these results show the biggest potencial in production fibrinolytic enzyme by Streptomyces.info:eu-repo/semantics/publishedVersio

    A MULTICENTER, OBSERVATIONAL, AMBISPECTIVE STUDY EVALUATING EFFICACY AND SAFETY OF GENERIC IMATINIB COMPARED TO GLEEVEC IN CHRONIC MYELOGENOUS LEUKEMIA IN CHRONIC PHASE-3 MONTHS RESPONSE ANALYSIS

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    Univ Estadual Campinas, Hematol & Hemotherapy Ctr, Campinas, SP, BrazilUniv Fed Minas Gerais, Hosp Clin, Belo Horizonte, MG, BrazilInst Nacl Cancer, Rio De Janeiro, BrazilFac Med, Sao Paulo, BrazilUniv Sao Paulo, Sao Paulo, BrazilHemorio, Rio De Janeiro, BrazilHosp Clin Porto Alegre, Porto Alegre, RS, BrazilCtr Pesquisa Oncol Santa Catarina, Florianopolis, SC, BrazilUniv Fed Bahia, Salvador, BA, BrazilUniv Fed Sao Paulo, Sao Paulo, BrazilInst Estudos & Pesquisas Sao Lucas, Sao Paulo, BrazilUniv Estadual Campinas, Campinas, SP, BrazilUniv Fed Sao Paulo, Sao Paulo, BrazilWeb of Scienc

    Structure and Fate of Nanoparticles Designed for the Nasal Delivery of Poorly Soluble Drugs

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    Nanoparticles are promising mediators to enable nasal systemic and brain delivery of active compounds. However, the possibility of reaching therapeutically relevant levels of exogenous molecules in the body is strongly reliant on the ability of the nanoparticles to overcome biological barriers. In this work, three paradigmatic nanoformulations vehiculating the poorly soluble model drug simvastatin were addressed: (i) hybrid lecithin/chitosan nanoparticles (LCNs), (ii) polymeric poly-ϵ-caprolactone nanocapsules stabilized with the nonionic surfactant polysorbate 80 (PCL_P80), and (iii) polymeric poly-ϵ-caprolactone nanocapsules stabilized with a polysaccharide-based surfactant, i.e., sodium caproyl hyaluronate (PCL_SCH). The three nanosystems were investigated for their physicochemical and structural properties and for their impact on the biopharmaceutical aspects critical for nasal and nose-to-brain delivery: biocompatibility, drug release, mucoadhesion, and permeation across the nasal mucosa. All three nanoformulations were highly reproducible, with small particle size (∼200 nm), narrow size distribution (polydispersity index (PI) < 0.2), and high drug encapsulation efficiency (>97%). Nanoparticle composition, surface charge, and internal structure (multilayered, core-shell or raspberry-like, as assessed by small-angle neutron scattering, SANS) were demonstrated to have an impact on both the drug-release profile and, strikingly, its behavior at the biological interface. The interaction with the mucus layer and the kinetics and extent of transport of the drug across the excised animal nasal epithelium were modulated by nanoparticle structure and surface. In fact, all of the produced nanoparticles improved simvastatin transport across the epithelial barrier of the nasal cavity as compared to a traditional formulation. Interestingly, however, the permeation enhancement was achieved via two distinct pathways: (a) enhanced mucoadhesion for hybrid LCN accompanied by fast mucosal permeation of the model drug, or (b) mucopenetration and an improved uptake and potential transport of whole PCL_P80 and PCL_SCH nanocapsules with delayed boost of permeation across the nasal mucosa. The correlation between nanoparticle structure and its biopharmaceutical properties appears to be a pivotal point for the development of novel platforms suitable for systemic and brain delivery of pharmaceutical compounds via intranasal administration
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