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The 15-deoxy-Δ12,14-PG J2 (15d-PGJ2) has demonstrated excellent anti-inflammatory results in different experimental models. It can be used with a polymeric nanostructure system for modified drug release, which can change the therapeutic properties of the active principle, leading to increased stability and slower/prolonged release. The aim of the current study was to test a nanotechnological formulation as a carrier for 15d-PGJ2, and to investigate the immunomodulatory effects of this formulation in a mouse periodontitis model. Poly (D,L-lactide-coglycolide) nanocapsules (NC) were used to encapsulate 15d-PGJ2. BALB/c mice were infected on days 0, 2, and 4 with Aggregatibacter actinomycetemcomitans and divided into groups (n = 5) that were treated daily during 15 d with 1, 3, or 10 μg/kg 15d-PGJ2-NC. The animals were sacrificed, the submandibular lymph nodes were removed for FACS analysis, and the jaws were analyzed for bone resorption by morphometry. Immunoinflammatory markers in the gingival tissue were analyzed by reverse transcriptase-quantitative PCR, Western blotting, or ELISA. Infected animals treated with the 15d-PGJ2-NC presented lower bone resorption than infected animals without treatment (p < 0.05). Furthermore, infected animals treated with 10 μg/kg 15d-PGJ2-NC had a reduction of CD4+CD25+FOXP3+ cells and CD4/CD8 ratio in the submandibular lymph node (p < 0.05). Moreover, CD55 was upregulated, whereas RANKL was downregulated in the gingival tissue of the 10 μg/kg treated group (p < 0.05). Several proinflammatory cytokines were decreased in the group treated with 10 μg/kg 15d-PGJ2-NC, and high amounts of 15d-PGJ2 were observed in the gingiva. In conclusion, the 15d-PGJ2-NC formulation presented immunomodulatory effects, decreasing bone resorption and inflammatory responses in a periodontitis mouse model.

a b s t r a c tThe purpose of this work was to develop a modified release system for the herbicide ametryn by encapsulating the active substance in biodegradable polymer microparticles produced using the polymers poly(hydroxybutyrate) (PHB) or poly(hydroxybutyrate-valerate) (PHBV), in order to both improve the herbicidal action and reduce environmental toxicity. PHB or PHBV microparticles containing ametryn were prepared and the efficiencies of herbicide association and loading were evaluated, presenting similar values of approximately 40%. The microparticles were characterized by scanning electron microscopy (SEM), which showed that the average sizes of the PHB and PHBV microparticles were 5.92 ± 0.74 m and 5.63 ± 0.68 m, respectively. The ametryn release profile was modified when it was encapsulated in the microparticles, with slower and more sustained release compared to the release profile of pure ametryn. When ametryn was associated with the PHB and PHBV microparticles, the amount of herbicide released in the same period of time was significantly reduced, declining to 75% and 87%, respectively. For both types of microparticle (PHB and PHBV) the release of ametryn was by diffusion processes due to anomalous transport (governed by diffusion and relaxation of the polymer chains), which did not follow Fick's laws of diffusion. The results presented in this paper are promising, in view of the successful encapsulation of ametryn in PHB or PHBV polymer microparticles, and indications that this system may help reduce the impacts caused by the herbicide, making it an environmentally safer alternative.

No abstract

Bupivacaine (BVC; S75–R25, NovaBupi® is an amide-type local anesthetic. Sodium alginate is a water-soluble linear polysaccharide. The present study reports the development of alginate/bis(2-ethylhexyl) sulfosuccinate (AOT) and alginate/chitosan nanoparticle formulations containing BVC (0.5%). The amounts of BVC associated in the alginate/AOT and alginate/chitosan nanoparticles were 87 ± 1.5 and 76 ± 0.9%, respectively. The average diameters and zeta potentials of the nanoparticles were measured for 30 days, and the results demonstrated the good stability of these particles in solution. The in vitro release kinetics showed a different behavior for the release profile of BVC in solution, compared with BVC-loaded alginate nanoparticles. In vitro and in vivo assays showed that alginate–chitosan BVC (BVC(ALG–CHIT)) and alginate–AOT BVC (BVC(ALG–AOT)) presented low cytotoxicity in 3T3-fibroblasts, enhanced the intensity, and prolonged the duration of motor and sensory blockades in a sciatic nerve blockade model.

Results from our study provide useful perspectives on selection of the primary materials needed to produce suspensions of polymeric nanocapsules able to act as carriers of BZC, with potential future application in the treatment of pain.

No abstract

This work describes the development of poly-ε-caprolactone nanocapsules (PCL-NC) and solid lipid nanoparticles (SLN) aiming delivery for articaine (ATC), in order to improve its chemical stability in semi-solid preparations looking forward their use for skin delivery. The nanoparticles were characterized by size, polydispersity index, and pH. Cellular viability was evaluated using the MTT test and the in vitro release kinetics was determined using a two-compartment model. The hydrogels with nanoparticle suspensions were characterized considering their rheological aspects and in vitro permeation across artificial membranes. Colloidal stability was satisfactory, since the formulations did not present major alterations during 120 days. High ATC encapsulation was achieved (78% for PCL-NC and 65% for SLN). The release profile of PCL-NC-ATC was slower, compared to the free molecule and SLN-ATC. MTT experiments showed the nanosystems were capable to increase cellular viability compared with free ATC. The hydrogels showed good consistency, homogeneity, and stability and presented pseudoplastic behavior with thixotropy, improving drug efficacy in clinical applications. The gel based on PCL-NC showed faster onset of activity and flux of 35.68 ± 1.98 μg/cm2/h, which then continued for up to 8 h. This study opens up prospects for employment of nanoparticulate systems for modified release of ATC.