Nanoparticles containing ß-cyclodextrin potentially useful for the treatment of Niemann-Pick C.

ß-Cyclodextrin (ß-CD) is being considered a promising therapy for Niemann-Pick C (NPC) disease because of its ability to mobilise the entrapped cholesterol from lysosomes, however, a major limitation is its inability to cross the blood-brain barrier (BBB) and address the central nervous system (CNS) manifestations of the disease. Considering this, we aimed to design nanoparticles able to cross the BBB and deliver ß-CD into the CNS lysosomes. The physicochemical characteristics of ß-CD-loaded nanoparticles were evaluated by dynamic light scattering, small-angle X-ray scattering, and cryogenic transmission electron microscopy. The in vitro analyses were performed with NPC dermal fibroblasts and the ß-CD-loaded nanoparticles were tracked in vivo. The nanoparticles showed a mean diameter around 120 nm with a disordered bicontinuous inner structure. The nanoparticles did not cause decrease in cell viability, impairment in the antioxidant enzymes activity, damage to biomolecules or release of reactive species in NPC dermal fibroblasts; also, they did not induce genotoxicity or alter the mitochondrial function in healthy fibroblasts. The ß-CD-loaded nanoparticles were taken up by lysosomes reducing the cholesterol accumulated in NPC fibroblasts and reached the CNS of mice more intensely than other organs, demonstrating advantages compared to the free ß-CD. The results demonstrated the potential of the ß-CD-loaded nanoparticles in reducing the brain impairment of NPC.

Anti-Inflammatory Effects of Resveratrol: Mechanistic Insights.

Inflammation is the principal response invoked by the body to address injuries. Despite inflammation constituting a crucial component of tissue repair, it is well known that unchecked or chronic inflammation becomes deleterious, leading to progressive tissue damage. Studies over the past years focused on foods rich in polyphenols with anti-inflammatory and immunomodulatory properties, since inflammation was recognized to play a central role in several diseases. In this review, we discuss the beneficial effects of resveratrol, the most widely investigated polyphenol, on cancer and neurodegenerative, respiratory, metabolic, and cardiovascular diseases. We highlight how resveratrol, despite its unfavorable pharmacokinetics, can modulate the inflammatory pathways underlying those diseases, and we identify future opportunities for the evaluation of its clinical feasibility.

Maxillary Hypoplasia: Differential Diagnosis of Nasal Obstruction in Infants.

Maxillary hypoplasia (MH) is a rare cause of respiratory dysfunction in infants and may occur in association with genetic abnormalities or as an isolated condition. It is included in the differential diagnosis of congenital nasal obstruction. This paper seeks to report a case series of infants with MH, discuss methods for its diagnosis, and compare computed tomography (CT) measurements of nasal cavities of infants with MH and without craniomaxillofacial abnormalities. The therapeutic approach in each patient is also described. All infants with MH admitted to a tertiary hospital between 2012 and 2015 were included. Baseline nasal endoscopy was performed at bedside. The width of the infants' nasal cavities was measured by a radiologist with experience in CT scanning of facial bones. Control patients were infants of matched sex and similar age who underwent head CT scanning for various reasons. Overall, 8 infants with MH and 8 controls were assessed. All nasal cavity dimensions of infants with MH were significantly smaller than those of control subjects. The authors conclude that the diagnosis of MH should be considered in infants with nasal obstruction and nasal cavity narrowing at nasal endoscopy.

Prednisolone-loaded nanocapsules as ocular drug delivery system: development, in vitro drug release and eye toxicity.

OBJECTIVE: To develop non-toxic aqueous ocular drug delivery systems containing prednisolone by means of its nanoencapsulation. MATERIALS AND METHODS: Nanocapsules were prepared by interfacial deposition of preformed polymer [poly(ε-caprolactone) or Eudragit® RS100]. Particle size distribution was determined by laser diffractometry, photon correlation spectroscopy and nanoparticle tracking analysis. Ocular irritation and cytotoxicity were evaluated in vitro on the chorioallantoic membrane (CAM) and rabbit corneal epithelial cell line, respectively. RESULTS AND DISCUSSION: Nanocapsules showed mean particle sizes between 100 and 300 nm and prednisolone encapsulation efficiency of around 50%. Controlled release of prednisolone occurred for 5 h for both formulations according to the biexponential model. Both formulations were found to be non-irritant in the CAM test and non-cytotoxic toward rabbit corneal epithelial cells. CONCLUSIONS: Encapsulation of prednisolone in nanocapsules was reported for the first time, being suitable for producing eye drops for the treatment of ocular inflammatory and no eye toxicity was indicated.

Castor oil and mineral oil nanoemulsion: development and compatibility with a soft contact lens.

CONTEXT: The non-invasive ophthalmic therapy has a drawback: low residence time in the eye socket. Nanoparticles and contact lenses have been studied as promising ocular drug delivery systems. OBJECTIVE: To develop a nanoemulsion and evaluate its compatibility with a soft contact lens as a potential strategy for ocular delivery. MATERIALS AND METHODS: The formulations were developed by spontaneous emulsification and fully characterized. Two drops of nanoemulsion were instilled on the surface of a commercial contact lens and its transparency was measured using a UV-Vis spectrophotometer. Before and after the instillation of the drops, the morphology (scanning electron microscopy - SEM) and ion permeability of the lenses were analyzed. RESULTS: The formulations had a mean particle size of 234 nm, polydispersity below 0.16, zeta potential of -8.56 ± 3.49 mV, slightly acid pH, viscosity ≈1.2 mPa s(-1) and spherical-shaped particles. Nanoemulsion was non-irritant (hen's egg test-chorioallantoic membrane), which was confirmed by the cytotoxicity studies in the SIRC cell cultures. After instillation, SEM analysis showed nanodroplets inside and on the surface of the lenses, although their transparency remained near 100%. No significant differences were found between lens ion permeability coefficients before and after instillation. CONCLUSIONS: Formulations presented appropriate physicochemical characteristics and suitability for ocular application. The contact lens remained transparent and ion-permeable after association with the formulation.

Neuroinflammation in Glioblastoma: The Role of the Microenvironment in Tumour Progression.

Glioblastoma (GBM) stands as the most aggressive and lethal among the main types of primary brain tumors. It exhibits malignant growth, infiltrating the brain tissue, and displaying resistance toward treatment. GBM is a complex disease characterized by high degrees of heterogeneity. During tumour growth, microglia and astrocytes, among other cells, infiltrate the tumour microenvironment and contribute extensively to gliomagenesis. Tumour-associated macrophages (TAMs), either of peripheral origin or representing brain-intrinsic microglia, are the most numerous nonneoplastic populations in the tumour microenvironment in GBM. The complex heterogeneous nature of GBM cells is facilitated by the local inflammatory tumour microenvironment, which mostly induces tumour aggressiveness and drug resistance. The immunosuppressive tumour microenvironment of GBM provides multiple pathways for tumour immune evasion, contributing to tumour progression. Additionally, TAMs and astrocytes can contribute to tumour progression through the release of cytokines and activation of signalling pathways. In this review, we summarize the role of the microenvironment in GBM progression, focusing on neuroinflammation. These recent advancements in research of the microenvironment hold the potential to offer a promising approach to the treatment of GBM in the coming times.

Beneficial Effects of Capybara Oil Supplementation on Steatosis and Liver Apoptosis in Obese Mice.

Obesity is a complex chronic disease characterized by excess body fat (adipose) that is harmful to health and has been a major global health problem. It may be associated with several diseases, such as nonalcoholic fatty liver disease (NAFLD). Polyunsaturated fatty acids (PUFA) are lipid mediators that have anti-inflammatory characteristics and can be found in animals and plants, with capybara oil (CO) being a promising source. So, we intend to evaluate the hepatic pathophysiological alterations in C57Bl/6 mice with NAFLD, caused by obesity, and the possible beneficial effects of OC in the treatment of this disease. Eighteen 3-month-old male C57Bl/6 mice received a control or high-fat diet for 18 weeks. From the 15th to the 18th week, the animals received treatment-through orogastric gavage-with placebo or free capybara oil (5 g/kg). Parameters inherent to body mass, glucose tolerance, evaluation of liver enzymes, percentage of hepatic steatosis, oxidative stress, the process of cell death with the apoptotic biomarkers (Bax, Bcl2, and Cytochrome C), and the ultrastructure of hepatocytes were analyzed. Even though the treatment with CO was not able to disassemble the effects on the physiological parameters, it proved to be beneficial in reversing the morphological and ultrastructural damage present in the hepatocytes. Thus, demonstrating that CO has beneficial effects in reducing steatosis and the apoptotic pathway, it is a promising treatment for NAFLD.

Free and nanoencapsulated curcumin suppress ß-amyloid-induced cognitive impairments in rats: involvement of BDNF and Akt/GSK-3ß signaling pathway.

Alzheimer's disease (AD), a neurodegenerative disorder exhibiting progressive loss of memory and cognitive functions, is characterized by the presence of neuritic plaques composed of neurofibrillary tangles and ß-amyloid (Aß) peptide. Drug delivery to the brain still remains highly challenging for the treatment of AD. Several studies have been shown that curcumin is associated with anti-amyloidogenic properties, but therapeutic application of its beneficial effects is limited. Here we investigated possible mechanisms involved in curcumin protection against Aß(1-42)-induced cognitive impairment and, due to its poor bioavailability, we developed curcumin-loaded lipid-core nanocapsules in an attempt to improve the neuroprotective effect of this polyphenol. Animals received a single intracerebroventricular injection of Aß(1-42) and they were administered either free curcumin or curcumin-loaded lipid-core nanocapsules (Cur-LNC) intraperitoneally for 10days. Aß(1-42)-infused animals showed a significant impairment on learning-memory ability, which was paralleled by a significant decrease in hippocampal synaptophysin levels. Furthermore, animals exhibited activated astrocytes and microglial cells, as well as disturbance in BDNF expression and Akt/GSK-3ß signaling pathway, beyond tau hyperphosphorylation. Our findings demonstrate that administration of curcumin was effective in preventing behavioral impairments, neuroinflammation, tau hyperphosphorylation as well as cell signaling disturbances triggered by Aß in vivo. Of high interest, Cur-LNC in a dose 20-fold lower presented similar neuroprotective results compared to the effective dose of free curcumin. Considered overall, the data suggest that curcumin is a potential therapeutic agent for neurocognition and nanoencapsulation of curcumin in LNC might constitute a promising therapeutic alternative in the treatment of neurodegenerative diseases such as AD.

Capybara Oil Improves Renal Pathophysiology and Inflammation in Obese Mice.

Obesity is an inflammatory disease associated with secondary diseases such as kidney disease, which can cause lipotoxicity, inflammation and loss of organ function. Polyunsaturated fatty acids act in the production of lipid mediators and have anti-inflammatory characteristics. In this work, the objective was to evaluate renal histopathology in obese mice and the effects of treatment with capybara oil (CO) (5000 mg/kg/day for 4 weeks). Parameters such as body mass, lipid profile, systolic blood pressure, urinary creatinine and protein excretion, structure and ultrastructure of the renal cortex, fibrosis, tissue inflammation and oxidative stress were analyzed. CO treatment in obese mice showed improvement in the lipid profile and reduction in systolic blood pressure levels, in addition to beneficial remodeling of the renal cortex. Our data demonstrated that CO decreased inflammation, oxidative stress and renal fibrosis, as evidenced by quantifying the expression of TNF-α, IL-10, CAT, SOD, α-SMA and TGF-ß. Although treatment with CO did not show improvement in renal function, ultrastructural analysis showed that the treatment was effective in restoring podocytes and pedicels, with restructuring of the glomerular filtration barrier. These results demonstrate, for the first time, that treatment with CO is effective in reducing kidney damage, being considered a promising treatment for obesity.

Overexpression of NTPDase2 in gliomas promotes systemic inflammation and pulmonary injury.

Gliomas are the most common and devastating type of primary brain tumor. Many non-neoplastic cells, including immune cells, comprise the tumor microenvironment where they create a milieu that appears to dictate cancer development. ATP and the phosphohydrolytic products ADP and adenosine by activating P2 and P1 receptors may participate in these interactions among malignant and immune cells. Purinergic receptor-mediated cell communication is closely regulated by ectonucleotidases, such as by members of the ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) family, which hydrolyze extracellular nucleotides. We have shown that gliomas, unlike astrocytes, exhibit low NTPDase activity. Furthermore, ATP induces glioma cell proliferation and the co-administration of apyrase decreases progression of injected cells in vivo. We have previously shown that NTPDase2 reconstitution dramatically increases tumor growth in vivo. Here we evaluated whether NTPDase2 reconstitution to gliomas modulates systemic inflammatory responses. We observed that NTPDase2 overexpression modulated pro-inflammatory cytokine production and platelet reactivity. Additionally, pathological alterations in the lungs were observed in rats bearing these tumors. Our results suggest that disruption of purinergic signaling via ADP accumulation creates an inflammatory state that may promote tumor spread and dictate clinical progression.

Resveratrol-Loaded Lipid-Core Nanocapsules Modulate Acute Lung Inflammation and Oxidative Imbalance Induced by LPS in Mice.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are inflammatory and oxidative imbalance lung conditions with no successful pharmacological therapy and a high mortality rate. Resveratrol (RSV) is a plant-derived stilbene that presents anti-inflammatory and antioxidant effects. However, its therapeutic application remains limited due to its poor bioavailability, which can be solved by the use of nanocarriers. Previously, we demonstrated that nanoencapsulated RSV (RSV-LNC) pre-treatment, performed 4 h before lipopolysaccharide (LPS) stimulation in mice, increased its anti-inflammatory properties. In this study, we evaluated the anti-inflammatory and antioxidant effects, and lung distribution of RSV-LNCs administered therapeutically (6 h post LPS exposure) in a lung injury mouse model. The results showed that RSV-LNCs posttreatment improved lung function and diminished pulmonary inflammation. Moreover, RSV-LNC treatment enhanced the antioxidant catalase level together with a decrease in the oxidative biomarker in mouse lungs, which was accompanied by an increase in pulmonary Nrf2 antioxidant expression. Finally, the presence of RSV in lung tissue was significantly detected when mice received RSV-LNCs but not when they received RSV in its free form. Together, our results confirm that RSV nanoencapsulation promotes an increase in RSV bioavailability, enhancing its therapeutic effects in an LPS-induced lung injury model.

Amyloid-beta neurotoxicity in organotypic culture is attenuated by melatonin: involvement of GSK-3beta, tau and neuroinflammation.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by accumulation of extracellular deposits of amyloid-beta (Abeta) peptide in brain regions that are important for memory and cognition. The buildup of Abeta aggregates in the AD is followed by the formation of intracellular neurofibrillary tangles and activation of neuroinflammatory reactions. The present study investigated whether melatonin possesses a neuroprotective effect against Abeta-induced toxicity. For this purpose, organotypic hippocampal slices were cultured and exposed to 25 microm of Abeta(25-35) in the absence or in the presence of melatonin (25, 50, or 100 microm). In addition, the authors have investigated the involvement of GSK-3beta, tau protein, astroglial, and microglial activation, and cytokine levels in the melatonin protection against Abeta-induced neurotoxicity. Melatonin prevented the cell damage in hippocampus induced by the exposure to Abeta(25-35). In addition, melatonin significantly reduced the activation of GSK-3beta, the phosphorylation of tau protein, the glial activation and the Abeta-induced increase of TNF-alpha and IL-6 levels. On the basis of these findings, we speculate that melatonin may provide an effective therapeutic strategy for AD, by attenuating Abeta-induced phosphorylation of tau protein, and preventing GSK-3beta activation and neuroinflammation.

The Role of Short-Chain Fatty Acids From Gut Microbiota in Gut-Brain Communication.

A substantial body of evidence supports that the gut microbiota plays a pivotal role in the regulation of metabolic, endocrine and immune functions. In recent years, there has been growing recognition of the involvement of the gut microbiota in the modulation of multiple neurochemical pathways through the highly interconnected gut-brain axis. Although amazing scientific breakthroughs over the last few years have expanded our knowledge on the communication between microbes and their hosts, the underpinnings of microbiota-gut-brain crosstalk remain to be determined. Short-chain fatty acids (SCFAs), the main metabolites produced in the colon by bacterial fermentation of dietary fibers and resistant starch, are speculated to play a key role in neuro-immunoendocrine regulation. However, the underlying mechanisms through which SCFAs might influence brain physiology and behavior have not been fully elucidated. In this review, we outline the current knowledge about the involvement of SCFAs in microbiota-gut-brain interactions. We also highlight how the development of future treatments for central nervous system (CNS) disorders can take advantage of the intimate and mutual interactions of the gut microbiota with the brain by exploring the role of SCFAs in the regulation of neuro-immunoendocrine function.

Pequi (Caryocar brasiliense Cambess)-Loaded Nanoemulsion, Orally Delivered, Modulates Inflammation in LPS-Induced Acute Lung Injury in Mice.

Pequi is a Brazilian fruit used in folk medicine for pulmonary diseases treatment, but its oil presents bioavailability limitations. The use of nanocarriers can overcome this limitation. We developed nanoemulsions containing pequi oil (pequi-NE) and evaluated their effects in a lipopolysaccharide (LPS)-induced lung injury model. Free pequi oil or pequi-NE (20 mg/kg) was orally administered to A/J mice 16 and 4 h prior to intranasal LPS exposure, and the analyses were performed 24 h after LPS provocation. The physicochemical results revealed that pequi-NE comprised particles with mean diameter of 174-223 nm, low polydispersity index (0.11 ± 0.01), zeta potential of -7.13 ± 0.08 mV, and pH of 5.83 ± 0.12. In vivo evaluation showed that free pequi oil pretreatment reduced the influx of inflammatory cells into bronchoalveolar fluid (BALF), while pequi-NE completely abolished leukocyte accumulation. Moreover, pequi-NE, but not free pequi oil, reduced myeloperoxidase (MPO), TNF-α, IL-1ß, IL-6, MCP-1, and KC levels. Similar anti-inflammatory effects were observed when LPS-exposed animals were pre-treated with the nanoemulsion containing pequi or oleic acid. These results suggest that the use of nanoemulsions as carriers enhances the anti-inflammatory properties of oleic acid-containing pequi oil. Moreover, pequi's beneficial effect is likely due its high levels of oleic acid.

Improvement of Resveratrol Effects When Combined with Rice Oil in Rat Models of Inflammation.

This study investigated the effects of systemic treatment with a new formulation of resveratrol (RSV) vehicled in rice oil (RSVO) in experimental rat models of inflammation. Male Wistar rats were evaluated in the following in vivo models: carrageenan-induced acute edema, complete Freund's adjuvant (CFA)-evoked sub-chronic edema, and CFA-induced polyarthritis. The animals were treated orally with RSVO (10-15 mg/kg) or RSV (100-200 mg/kg), depending on the experimental protocol. RSV was more effective than RSVO in carrageenan-elicited acute edema when dosed in either prophylactic or therapeutic schemes of administration. However, the repeated RSVO administration, at 10-fold lower doses, exhibited superior anti-inflammatory actions in either the sub-chronic edema or the chronic polyarthritis model elicited by CFA, when compared with RSV. The novel formulation RSVO displayed a lower plasma biotransformation when compared with the RSV-treated group-46% versus 88% of metabolites, respectively. RSVO also prevented polyarthritis-related cartilage destruction, an effect that might rely on the inhibition of the pro-inflammatory cytokine interleukin-6 (IL-6), associated with an increase of the anti-inflammatory cytokine interleukin-10 (IL-10). Noteworthy, the long-term administration of RSVO did not elicit any gastrointestinal harm. Our study revealed that RSVO was notably effective in the long-term inflammatory and degenerative responses triggered by CFA. This innovative formulation might well represent a promising alternative for treating chronic inflammatory diseases, such as arthritis.

Intranasal administration of budesonide-loaded nanocapsule microagglomerates as an innovative strategy for asthma treatment.

The co-existence with rhinitis limits the control of asthma. Compared with oral H1 receptor antagonists, intranasal corticosteroids have been demonstrated to provide greater relief of all symptoms of rhinitis and are recommended as first-line treatment for allergic rhinitis. Intrinsic limitations of nasal delivery, such as the presence of the protective mucous layer, the relentless mucociliary clearance, and the consequent reduced residence time of the formulation in the nasal cavity, limit budesonide efficacy to the treatment of local nasal symptoms. To overcome these limitations and to enable the treatment of asthma via nasal administration, we developed a budesonide-loaded lipid-core nanocapsule (BudNC) microagglomerate powder by spray-drying using a one-step innovative approach. BudNC was obtained, as a white powder, using L-leucine as adjuvant with 75 ± 6% yield. The powder showed a bimodal size distribution curve by laser diffraction with a principal peak just above 3 µm and a second one around 0.45 µm and a drug content determined by HPLC of 8.7 mg of budesonide per gram. In vivo after nasal administration, BudNC showed an improved efficacy in terms of reduction of immune cell influx; production of eotaxin-1, the main inflammatory chemokine; and arrest of airways remodeling when compared with a commercial budesonide product in both short- and long-term asthma models. In addition, data showed that the results in the long-term asthma model were more compelling than the results obtained in the short-term model. Graphical abstract.

Selective NTPDase2 expression modulates in vivo rat glioma growth.

The ectonucleoside triphosphate diphosphohydrolases (E-NTPDases) are a family of ectoenzymes that hydrolyze extracellular nucleotides, thereby modulating purinergic signaling. Gliomas have low expression of all E-NTPDases, particularly NTPDase2, when compared to astrocytes in culture. Nucleotides induce glioma proliferation and ATP, although potentially neurotoxic, does not evoke cytotoxic action on the majority of glioma cultures. We have previously shown that the co-injection of apyrase with gliomas decreases glioma progression. Here, we tested whether selective re-establishment of NTPDase2 expression would affect glioma growth. NTPDase2 overexpression in C6 glioma cells had no effect on in vitro proliferation but dramatically increased tumor growth and malignant characteristics in vivo. Additionally, a sizable platelet sequestration in the tumor area and an increase in CD31 or platelet/endothelial cell adhesion molecule-1 (PECAM-1), vascular endothelial growth factor and OX-42 immunostaining were observed in C6-Enhanced Yellow Fluorescent Protein (EYFP)/NTPDase2-derived gliomas when compared to controls. Treatment with clopidogrel, a P2Y(12) antagonist with anti-platelet properties, decreased these parameters to control levels. These data suggest that the ADP derived from NTPDase2 activity stimulates platelet migration to the tumor area and that NTPDase2, by regulating angiogenesis and inflammation, seems to play an important role in tumor progression. In conclusion, our results point to the involvement of purinergic signaling in glioma progression.

A comparative study of ectonucleotidase and P2 receptor mRNA profiles in C6 cell line cultures and C6 ex vivo glioma model.

Glioblastoma multiforme is the most common type of primary brain tumour and has the worst clinical outcome. Nucleotides represent an important class of extracellular molecules involved in cell proliferation, differentiation and apoptosis. Alterations in purinergic signalling have been implicated in pathological processes, such as cancer, and glioma cell lines are widely employed as a model to study the biology of brain tumours. Increasing evidence, however, suggests that glioma cell lines may not present all the phenotypic and genetic characteristics of the primary tumours. We have compared the biological characteristics of C6 rat glioma cells in culture and the same cells after their implantation in the rat brain and growth in culture (denominated as the C6 ex vivo culture model). Parameters evaluated included cell morphology, differentiation, angiogenic markers, purinergic receptors and ecto-nucleotidase mRNA profile/enzymatic activity. Analysis of the C6 glioma cell line and C6 ex vivo glioma cultures revealed distinct cell morphologies, although cell differentiation and angiogenic marker expressions were similar. Both glioma models co-expressed multiple P2X and P2Y receptor subtypes with some differences. In addition, the C6 glioma cell line and C6 ex vivo glioma cultures exhibited similar extracellular ATP metabolism and cell proliferation behaviour when exposed to cytotoxic ATP concentrations. Thus, the disruption of purinergic signalling is a feature shown not only by glioma cell lineages, but also by primary glioma cultures. Our results therefore suggest the participation of the purinergic system in glioma malignancy.

Orally delivered resveratrol-loaded lipid-core nanocapsules ameliorate LPS-induced acute lung injury via the ERK and PI3K/Akt pathways.

BACKGROUND: Resveratrol (RSV) has attracted interest as an alternative drug for the treatment of acute lung injury (ALI) and other pulmonary diseases, but its poor oral bioavailability is a limitation. In this study, we employed drug delivery nanotechnology to improve the stability, lung localization and efficacy of orally administered resveratrol to control lung damage leading to ALI. METHODS AND MATERIALS: RSV-loaded lipid-core nanocapsules (RSV-LNCs), prepared by interfacial deposition of biodegradable polymers, were given orally to A/J mice prior to lipopolysaccharide (LPS) intranasal instillation. Inflammatory changes, oxidative stress and lung tissue elastance were assessed 24 h after LPS challenge. RESULTS: RSV-LNCs (5 mg/kg), given 1, 4, 6 or 12 h but not 24 h before provocation, inhibited LPS-induced leukocyte accumulation in the bronchoalveolar fluid (BALF), whereas unloaded nanocapsules (ULNCs) or free RSV (5 mg/kg) were ineffective. RSV-LNCs (2.5-10 mg/kg) but not ULNCs or RSV improved lung function and prevented total leukocyte and neutrophil accumulation equally in both BALF and lung tissue when given 4 h before LPS challenge. Similar findings were seen concerning the generation of a range of pro-inflammatory cytokines such as IL-6, KC, MIP-1α, MIP-2, MCP-1 and RANTES in lung tissue. In addition, only RSV-LNCs inhibited MDA levels and SOD activity in parallel with blockade of the ERK and PI3K/Akt pathways following LPS provocation. CONCLUSION: Nanoformulation of RSV in biodegradable oil-core polymers is an effective strategy to improve the anti-ALI activity of RSV, suggesting that the modified-release formulation of this plant polyphenol may be of great value in clinical conditions associated with ALI and respiratory failure.

Ecto-5'-nucleotidase/CD73 inhibition by quercetin in the human U138MG glioma cell line.

Gliomas are the most malignant of the primary brain tumors. Nucleotides represent an important class of extracellular molecules that are crucial for the normal function of the nervous system. ATP and adenosine can stimulate cell proliferation in different glioma cell lines; the events induced by extracellular adenine nucleotides are controlled by the action of ecto-nucleotidases, which hydrolyze ATP into adenosine in the extracellular space. Recent studies have shown that quercetin has an anti-proliferative effect on the U138MG glioma cell line. Since evidence suggests that purinergic signaling is involved in the growth and progression of glioma and, taking into consideration the anti-proliferative effect elicited by quercetin in this tumor type, the aim of the present study was to better investigate the extracellular metabolism of AMP and evaluate the effect of quercetin on this system in the human U138MG glioma cell line. The adenine products secreted by glioma cells were first characterized; extracellular AMP was efficiently metabolized by the glioma culture, demonstrating a very active ecto-5'-NT/CD73. Quercetin was able to inhibit the ecto-5'-NT/CD73 activity and modulate its expression. In addition, the cell treatment with APCP (alpha,beta-methyleneadenosine-5'-diphosphate), an ecto-5'-NT/CD73 inhibitor, led to a significant reduction in glioma cell proliferation. We suggest that the inhibition of ecto-5'-NT/CD73 may result in a decrease in extracellular adenosine production with a consequent reduction in tumor progression.