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Effective inhibition of intestinal lipid uptake is an efficient strategy for the treatment of disorders related to lipid metabolism. Sterol O‐acyltransferase 2 (SOAT2) is responsible for the esterification of free cholesterol and fatty acids into cholesteryl esters. We found that intestine‐specific SOAT2 knockout (Soat2I‐KO) mice was capable to prevent the development of dietary induced obesity due to reduced intestinal lipid absorption. Soat2 siRNA/CS‐PLGA nanoparticle system was constructed to enable intestinal delivery and inhibition of Soat2. This nanoparticle system was composed of PLGA‐block‐PEG and chitosan specifically delivering Soat2 siRNAs into small intestines in mice, effectively inhibit intestinal lipid uptake and resolving obesity. In revealing the underlying mechanism by which intestinal SOAT2 regulating fatty acid uptake, enhanced CD36 ubiquitination degradation was found in enterocytes upon SOAT2 inhibition. Insufficient free cholesterol esterification promoted endoplasmic reticulum stress and recruitment of E3 ligase RNF5 to activate CD36 ubiquitination in SOAT2 knockdown enterocytes. This work demonstrates a potential modulatory function of intestinal SOAT2 on lipid uptake highlighting the therapeutic effect on obesity by targeting intestinal SOAT2, exhibiting promising translational relevance in the siRNA therapeutic–based treatment for obesity. [ABSTRACT FROM AUTHOR]

Background: Achilles tendon (AT) midsubstance injuries may heal suboptimally, especially in athletes. Transforming growth factor–beta 3 (TGF-β3) shows promise because of its recently discovered tendinogenic effects. Using poly(lactic-co-glycolic acid)-b-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles (NPs) may enhance the results by a sustained-release effect. Hypothesis: The application of TGF-β3 will enhance AT midsubstance healing, and the NP form will achieve better outcomes. Study Design: Controlled laboratory study. Methods: A total of 80 rats underwent unilateral AT transection and were divided into 4 groups: (1) control (C); (2) empty chitosan film (Ch); (3) chitosan film containing free TGF-β3 (ChT); and (4) chitosan film containing TGF-β3–loaded NPs (ChN). The animals were sacrificed at 3 and 6 weeks. Tendons were evaluated for morphology (length and cross-sectional area [CSA]), biomechanics (maximum load, stress, stiffness, and elastic modulus), histology, immunohistochemical quantification (types I and III collagen [COL1 and COL3]), and gene expression (COL1A1, COL3A1, scleraxis, and tenomodulin). Results: Morphologically, at 3 weeks, ChT (15 ± 2.7 mm) and ChN (15.6 ± 1.6 mm) were shorter than C (17.6 ± 1.8 mm) (P =.019 and =.004, respectively). At 6 weeks, the mean CSA of ChN (10.4 ± 1.9 mm2) was similar to that of intact tendons (6.4 ± 1.1 mm2) (P =.230), while the other groups were larger. Biomechanically, at 3 weeks, ChT (42.8 ± 4.9 N) had a higher maximum load than C (27 ± 9.1 N; P =.004) and Ch (29.2 ± 5.7 N; P =.005). At 6 weeks, ChN (26.9 ± 3.9 MPa) had similar maximum stress when compared with intact tendons (34.1 ± 7.8 MPa) (P =.121); the other groups were significantly lower. Histologically, at 6 weeks, the mean Movin score of ChN (4.5 ± 1.5) was lower than that of ChT (6.3 ± 1.8). Immunohistochemically, ChN had higher COL3 (1.469 ± 0.514) at 3 weeks and lower COL1 (1.129 ± 0.368) at 6 weeks. COL1A1 gene expression was higher in ChT and ChN at 3 weeks, but COL3A1 gene expression was higher in ChN. Conclusion: The application of TGF-β3 had a positive effect on AT midsubstance healing, and the sustained-release NP form improved the outcomes, more specifically accelerating the remodeling process. Clinical Relevance: This study demonstrated the effectiveness of TGF-β3 on tendon healing on a rat model, which is an important step toward clinical use. The novel method of using PLGA-b-PEG NPs as a drug-delivery system with sustained-release properties had promising results. [ABSTRACT FROM AUTHOR]

Ibuprofen is a non-steroidal anti-inflammatory drug for the treatment of Rheumatoid Arthritis and osteoarthritis. In this study, we prepared topical gel network for enhancement of ibuprofen penetration, maintenance of controlled release and increased patient compliance. Nanoparticles containing ibuprofen were prepared by means of emulsion formation/solvent diffusion method using synthesized copolymer. Nanoparticles were then conjugated with aminoethylmethacrylate, resulting in ibuprofen-loaded nanoparticles in PLGA-b-PEG-MA structure. Ibuprofen-loaded gel networks were developed by crosslinking nanoparticles via UV exposure. Suitability for topical application has been assessed through characterization of particle size, zeta potential, morphology, encapsulation efficiency, in vitro release, cytotoxicity and enhancement of in vitro wound healing. The mean diameter of nanoparticles was measured as 230 ± 20 nm. Gel network formulations with higher particle size (2800 ± 350 nm) and zeta potential (39.8 ± 9.2 mV), depending on conjugation of methacrylate within copolymeric structure, and having encapsulation efficacy of 73.6 ± 2.8% were prepared. The in vitro release of ibuprofen was sustained for more than 7 hours. Gel network improved collagen synthesis, type I collagen mRNA expression and fibrosis in dose dependent manner. Based on this, we can conclude that PLGA-b-PEG gel network might be a promising systems for the local delivery of ibuprofen in RA patients. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare the ɛ-viniferine and vincristine-loaded PLGA-b-PEG nanoparticle and to investigate advantages of these formulations on the cytotoxicity of HepG2 cells. Prepared nanoparticle has shown a homogeneous distribution with 113 ± 0.43 nm particle size and 0.323 ± 0.01 polydispersity index. Zeta potential was determined as −35.03 ± 1.0 mV. The drug-loading percentages were 6.01 ± 0.23 and 2.01 ± 0.07 for ɛ-viniferine and vincristine, respectively. The cellular uptake efficiency of coumarin-6-loaded nanoparticles was increased up to 87.8% after 4 h. Nanoparticles loaded with high concentrations of both drugs showed a cytotoxic effect on HepG2 cells, having the percentage of cell viability of between 43.23% and 47.37%. Unfortunately, the percentage of apoptotic cells after treated with drugs-loaded nanaoparticles (10.93%) was similar to free forms of drugs (12.1%) that might be due to low ɛ-viniferine release in biological pH at 24 h. [ABSTRACT FROM PUBLISHER]

Alzheimer's disease (AD) is an irreversible and progressive neurodegenerative disease that is caused by the irreversible loss of neurons in the hippocampus and cortex regions of the brain. Although the molecular mechanism of the disease is still unclear, the deposition of the amyloid beta proteins (senile plaques) in the extracellular synaptic spaces of the neocortex is suggested to play a major role in progress of AD. The increased activity of monoamine oxidase-B (MAO-B) in AD brains was suggested to cause oxidative damage, and MAO-B inhibitors have been reported to inhibit the neuronal degeneration. Selegiline, a selective MAO-B inhibitor, known to have beneficial effects in the brain regions which are rich by dopamine receptors, however, studies based on brain targeting of selegiline are limited. Since some recent studies showed the possible Aβ-fibril destabilizing effects of MAO inhibitors, present study was designed to (1) prepare the selective MAO-B inhibitor selegiline-loaded Poly (lactic-co-glycolic acid)-poly (ethylene glycol) (PLGA-b-PEG) nanoparticles (2) to investigate the in vitro Aβ-fibril destabilizing effect of the loaded particles. Selegiline-loaded PLGA-b-PEG nanoparticles were prepared by water-in-oil-in-water (W/O/W) emulsion solvent evaporation method. Destabilizing effect of these particles on the β-amiloid fibril (Aβ 1-40 and Aβ 1-42) formation was determined in vitro by evaluating the decrease in ThT fluorescence intensity and verified by AFM images. Nanoparticle prepared with 5 mg selegiline was found to be the one with highest encapsulation efficiency. Particle size and polydispersity index for this formulation were determined as 217 ± 15.5 nm and 0.321, respectively. For both fibril types, destabilizing effect were found to be increased by increasing incubation time until 6 h; and reached a plateau after the 6 h. Data showed that selegiline-loaded PLGA-b-PEG nanoparticles seem to be a promising drug carrier for destabilizing the β-amiloid fibrils in Alzheimer patients. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop polysorbate 80 coated and Atorvastatin loaded poly(lactic-co-glycolic acid)-block-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles and to investigate advantages of coating on nanoparticles for brain delivery of Atorvastatin. The nanoparticles were prepared by nanoprecipitation method. The effects of polymer concentration, PEG content and polysorbate 80 coating on the particle size, drug loading efficiency and release behaviour of nanoparticles were investigated. Additionally, cellular uptake and brain targeting of formulated nanoparticles were studied. Particle sizes were in the range of 30-172 nm depending on formulation parameters. Increasing the polymer concentration significantly increased the nanoparticle size. Decreasing the PEG content from 15% to 5% (w/w) in polymer composition increased the nanoparticle size from 69 to 172 nm. Both coated and uncoated polysorbate 80 nanoparticles were effectively internalised within the endothelial cells. Moreover, both types of nanoparticles were able to penetrate the blood brain barrier and reach the maximum in brain 1 h post injection. It was concluded that these nanoparticles are promising nanosystems for treatment of neurological disorders. [ABSTRACT FROM AUTHOR]