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Green Coffea arabica L. seed oil (GCO) has been used as an active cosmetic ingredient in many skin care products, due to its composition and balance of fatty acids. On the other hand, while roasted coffee oil (RCO) is mainly used for imparting aroma in the food industry, there is no data available to suggest its safety in cell-based model systems. In this context, the present study aims to evaluate the chemical composition of GCO, RCO, and their correspondent polar fractions (PFs); and assess their cytotoxicity and antioxidant potential in vitro. RCO and RCO PF exhibited significantly higher amounts of phenolic compounds, when compared to both GCO and GCO PF. In the DPPH assay, after 5 min of incubation, RCO inhibited about 80% of radicals, while GCO only achieved half of this activity. Similar results were also obtained for their PFs. Upon exposure to GCO, no cytotoxic effects were observed, in fact, there were slight increments in cell proliferation. Nevertheless, cell exposure to RCO led to significant decreases in cell viability. Increases in the concentration of coffee oil PFs were associated with correspondent relevant increased cytotoxicity. Upon hydrogen peroxide-induced oxidative stress, neither GCO nor RCO treatment were effective in protecting cells.

Polycaprolactone (PCL) fibers were produced by electrospinning using three collectors: rotating drum, static copper wires, and a rotating mandrel. The effect of collector design on the alignment and morphology of fibers was evaluated. The drum collector produced a typical tridimensional structure whereby the rotational speed mechanically stretches fibers and affects their diameter and alignment. Randomly oriented fibers with an average diameter of 1142 ± 391 nm were obtained at 0 rpm, while aligned fibers with an average diameter of 663 ± 334 nm were produced at 2000 rpm. Static copper wires produced a novel fiber pattern in which the degree of orientation of the fibers is related to the electrical field distribution along the collector. The best fiber alignment and lowest average fiber diameter (490 ± 131 nm) were obtained using parallel copper wires with a gap of 1 cm. Two main forces influenced the fibers produced by the rotating mandrel. First, the attraction of the electrical field by the collector induced the deposition of fibers parallel to its axis with an average diameter of 606 ± 329 nm. Second, the stretching force from the high-speed rotation induced the deposition of fused fibers transverse to the collector axis.

The species Cyathea phalerata Mart. is a tree fern, commonly known as “xaxim”, which is found in tropical and subtropical areas of Brazil. The present study investigated the mechanisms related with the vasorelaxant effects of an Ethyl Acetate Fraction (EAF) obtained from C. phalerata in rats’ thoracic aorta rings. In pre-contracted vessels, EAF (0.1–1000 μg/mL) caused a concentration-dependent relaxation. The endothelium denudation, the nitric oxide (NO) synthase and guanylyl cyclase inhibitor reduced the vasodilation, indicating the participation of NO/cGMP pathway in its effect. The relaxation of EAF was abolished in the absence of extracellular Ca2+ and was significantly decreased in the presence of Ca2+ entry blocker, suggesting that Ca2+ influx plays an important role in EAF effect and probably in eNOS activity. However, the PI3K/Akt pathway is not responsible for eNOS phosphorylation/activation. The vasodilator effect of EAF was partially inhibited by KCl 40 mM and almost totally abolished with L-NOARG + KCl 40 mM, indicating also the role of hyperpolarization in its effect. Calcium activated K+ channels are not involved in the EAF-induced hyperpolarization. The COX inhibitor, indomethacin, slightly reduced the vasodilation induced by EAF. In addition, EAF did not alter the relaxant effects of NO-donor, indicating that the relaxant activity cannot be attributed to free radical-scavenging properties. In conclusion, the present study showed that the EAF, causes an endothelium-dependent vasorelaxant effect in aorta that mainly involves the NO-cGMP pathway, hyperpolarization and prostanoids. The vasorelaxant activity of EAF can be attributed to the occurrence of polyphenol compounds., Graphical abstract Image 1, Highlights • An ethyl acetate fraction obtained from Cyathea phalerata induces vasodilatation. • EAF induced relaxation by an endothelium-dependent mechanism. • EAF increases the NO production and hyperpolarization that evoke vasodilation.

Jaboticaba is a fruit from a native tree to Brazil,Plinia peruviana. Jaboticaba peels are an important source of antioxidant molecules such as phenolic compounds. This study aimed to evaluatein vitrothe activity of a hydroalcoholic extract of jaboticaba fruit peels (HEJFP) in wound healing processes and antioxidant activity in murine fibroblasts (L929 cell line). HEJFP concentrations (0.5, 1, 5, 10, 25, 50, 100, and 200 µg/mL) were tested in MTT assay and cell proliferation was verified at 100 µg/mL after 24 h and at 25, 50, and 100 µg/mL after 48 h of extract exposure. Evaluation of antioxidant activity was performed at 0.5, 5, 25, 50, and 100 µg/mL HEJFP concentrations. Cell treatment with HEJFP at 25, 50, and 100 µg/mL for 24 h followed by H2O2exposure for 3 h showed a strong cytoprotective effect.In vitroscratch wound healing assay indicated that none of tested HEJFP concentrations (0.5, 5, 25, 50, and 100 µg/mL) were capable of increasing migration rate after 12 h of incubation. These results demonstrate a positive effect of HEJFP on the wound healing process on L929 fibroblasts cell line, probably due to the antioxidant activity exhibited by phytochemicals in the extract.

OBJECTIVE The aim of this work is to develop and characterize nanoemulsions containing jaboticaba extract (Plinia peruviana) aiming pharmaceutical and cosmetic applications. METHODS Nanoemulsions were prepared by high-pressure homogenization method using different concentrations of components (oil, surfactant, and extract) and homogenization pressures, in order to optimize the preparation conditions. Both unloaded and extract-loaded nanoemulsions were characterized according to their size, polydispersity, zeta potential, pH, morphology, and physical stability. Total phenolic and flavonoid contents in free jaboticaba extract and jaboticaba-loaded nanoemulsions were determined spectrophotometrically, while ellagic acid content was determined by high-performance liquid chromatography (HPLC) analysis. In vitro antioxidant activity was investigated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. RESULTS Colloidal dispersions exhibited a mean particle size around 200 nm, with monodisperse size distribution (PdI

Nanotechnology is an exciting emerging field with multiple applications in skin regeneration. Nanofibers have gained special attention in skin regeneration based on their structural similarity to the extracellular matrix. A wide variety of polymeric nanofibers with distinct properties have been developed and tested as scaffolds for skin regeneration. Besides providing support for tissue repair, nanofibrous materials can act as delivery systems for drugs, proteins, growth factors, and other molecules. Moreover, the morphology, biodegradability, and other functionalities of nanofibrous materials can be controlled towards specific conditions of wound healing. Other nanostructured drug delivery systems, such as nanoparticles, micelles, nanoemulsions, and liposomes, have been used to improve wound healing at different stages. These nanoscale delivery systems have demonstrated several benefits for the wound healing process, including reduced cytotoxicity of drugs, administration of poorly water-soluble drugs, improved skin penetration, controlled release properties, antimicrobial activity, and protection of drugs against light, temperature, enzymes or pH degradation, as well as stimulation of fibroblast proliferation and reduced inflammation.

Oxidative stress is a result of disturbance between the production of reactive oxygen species (ROS) and antioxidants defenses. Plant secondary metabolites can be used as exogenous antioxidants to prevent human oxidative stress-related diseases. This study aimed to determine the antioxidant and cytoprotective effects of jaboticaba fruit peel hydroalcoholic extracts against H 2 O 2 -induced oxidative stress in a murine fibroblast (L929 cell line) model. Ultra-high pressure hydroalcoholic extracts (50% ethanol, UP) were obtained over 4 h, with 1 h interval between collections. UP 3 h and UP 4 h extracts presented the highest and the lowest phenolic and flavonoid contents, respectively. Antioxidant capacity showed that 1 mg/ml extracts inhibited 90% of DPPH radical activity and UP 1 h extract had significant (p < 0.05) higher scavenging activity than other extracts at this concentration. After 24 h of exposure to UP 4 h extracts, cell viability was significantly increased when compared to control, UP 1 h, and UP 2 h extracts. When cells were previously treated with UP hydroalcoholic extracts followed by H 2 O 2 exposure, all extracts at 0.05 and 0.1 mg/ml exhibited significant (p < 0.05) cytoprotective effects in relation to control. Results demonstrated that jaboticaba fruit peel extracts are antioxidants and exert cytoprotective effects under H 2 O 2 -induced oxidative stress.

There is increasing evidence that hypercholesterolemia during midlife may represent a predictor of subsequent mild cognitive impairments and dementia decades later. However, the exact mechanism underlying this phenomenon remains unknown since plasmatic cholesterol is not able to cross the blood-brain barrier. In the present study, we evaluated the hypothesis that cognitive impairments triggered by hypercholesterolemia during aging may be related to brain oxidative stress and altered brain acetylcholinesterase (AChE) activity. We also performed a neuropathological investigation in order to analyze whether the cognitive impairments may be associated with stroke-related features. To address these questions we used three- and fourteen-month-old low-density lipoprotein receptor-deficient mice (LDLr-/-). The current findings provide new evidence that aged LDLr-/- mice, exposed to over three-fold cholesterol levels from early life, show working, spatial reference, and procedural memory impairments, without alterations in motor function. Antioxidant imbalance and oxidative damage were evidenced by a marked increase in lipid peroxidation (thiobarbituric acid reactive substances levels) and glutathione metabolism (increase in glutathione levels, glutathione reductase, and glutathione peroxidase activities) together with a significant increase in the AChE activity in the prefrontal cortex of aged hypercholesterolemic LDLr-/- mice. Notably, hypercholesterolemia was not related to brain infarcts and neurodegeneration in mice, independent of their age. These observations provide new evidence that hypercholesterolemia during aging triggers cognitive impairments on different types of learning and memory, accompanied by antioxidant imbalance, oxidative damage, and alterations of cholinergic signaling in brain areas associated with learning and memory processes, particularly in the prefrontal cortex.

Moderate wine intake (i.e., 1-2 glasses of wine a day) is associated with a reduced risk of morbidity and mortality from cardiovascular disease. The aim of this study was to evaluate the anti-atherosclerotic effects of a nonalcoholic ethyl acetate fraction (EAF) from a South Brazilian red wine obtained from Vitis labrusca grapes. Experiments were carried out on low-density lipoprotein (LDL) receptor knockout (LDLr⁻/⁻) mice, which were subjected to a hypercholesterolemic diet and treated with doses of EAF (3, 10, and 30 mg/kg) for 12 weeks. At the end of the treatment, the level of plasma lipids, the vascular reactivity, and the atherosclerotic lesions were evaluated. Our results demonstrated that the treatment with EAF at 3 mg/kg significantly decreased total cholesterol, triglycerides, and LDL plus very low-density lipoprotein levels compared with control hypercholesterolemic mice. The treatment of mice with EAF at 3 mg/kg also preserved the vasodilatation induced by acetylcholine on isolated thoracic aorta from hypercholesterolemic LDLr⁻/⁻ mice. This result is in agreement with the degree of lipid deposit on arteries. Taken together, the results show for the first time that the lowest concentration of an EAF obtained from a red wine produced in southern Brazil significantly reduced the progression of atherosclerosis in mice.

The present study describes the chemical composition and the antioxidant activity of spent coffee grounds and coffee husks extracts, obtained by supercritical fluid extraction (SFE) with CO(2) and with CO(2) and co-solvent. In order to evaluate the high pressure method in terms of process yield, extract composition and antioxidant activity, low pressure methods, such as ultrasound (UE) and soxhlet (SOX) with different organic solvents, were also applied to obtain the extracts. The conditions for the SFE were: temperatures of 313.15K, 323.15K and 333.15K and pressures from 100 bar to 300 bar. The SFE kinetics and the mathematical modeling of the overall extraction curves (OEC) were also investigated. The extracts obtained by LPE (low pressure extraction) with ethanol showed the best results for the global extraction yield (X(0)) when compared to SFE results. The best extraction yield was 15±2% for spent coffee grounds with ethanol and 3.1±04% for coffee husks. The antioxidant potential was evaluated by DPPH method, ABTS method and Folin-Ciocalteau method. The best antioxidant activity was showed by coffee husk extracts obtained by LPE. The quantification and the identification of the extracts were accomplished using HPLC analysis. The main compounds identified were caffeine and chlorogenic acid for the supercritical extracts from coffee husks.

Glutathione peroxidase (GPx) plays an important role in the antioxidant defense of the vascular wall, and its deficiency has been implicated in the development of atherosclerotic lesions. This study analyzed the potential of diphenyl diselenide (DD), a simple organoselenium compound with GPx-like activity, to reduce atherosclerosis. Herein, we demonstrate that oral treatment with low doses of DD potently reduced the formation of atherosclerotic lesion in hypercholesterolemic low-density lipoprotein (LDL) receptor knockout (LDLr −/−) mice. This reduction was accompanied by significantly improved endothelium-dependent vasorelaxation, lower nitrotyrosine and malondialdehyde levels, decrease in vessel-wall infiltration by inflammatory cells, and prevention of upregulation of the proatherogenic monocyte chemoattractant protein-1. Studies in J774 macrophage-like cells show that DD significantly decreased oxLDL-induced formation of foam cells and the generation of reactive oxygen species and inflammatory mediators. Our results reveal the antiatherogenic actions of DD by modulating intracellular signaling pathways related to antioxidant and anti-inflammatory responses.

We evaluated both in vitro and in vivo antitumoral properties of an isolated compound from Wilbrandia ebracteata, dihydrocucurbitacin-B (DHCB), using B16F10 cells (murine melanoma).We made use of MTT and (3)H-Thymidine assays to investigate the cell viability and cell proliferation, flow cytometry analysis to monitor cell cycle and apoptosis, western blot analysis to evaluate the expression of cell cycle proteins, imunofluorescence analysis and in vivo tumor growth and metastasis.Dihydrocucurbitacin-B significantly reduced cell proliferation without important effects on cells viability. DHCB lead cells to accumulate in G2/M phases accompanied by the appearance of polyploid cells, confirmed by fluorescence assays that demonstrated a remarkable alteration in the cell cytoskeleton and formation of binuclear cells. Annexin-V-FITC incorporation demonstrated that DHCB did not induce apoptosis. About 10 microg/mL DHCB was found to decrease cyclin-A, and especially in cyclin-B1. The in vivo experiments showed that DHCB treatment (once a day up to 12 days; p.o.) was able to reduce the tumor growth and lung metastasis up to 83.5 and 50.3%, respectively.Dihydrocucurbitacin-B reduces cell proliferation due to a decrease in the expression of cyclins, mainly cyclin-B1 and disruption of the actin cytoskeleton, arresting B16F10 cells in G2/M phase. Taken together, the in vitro and in vivo experiments suggest that DHCB was effective against cancer, however, it remains to be proved if DHCB will be a good candidate for drug development.

O estudo das interações entre células e seu substrato na engenharia de tecidos é de grande importância para determinação das propriedades biológicas dos implantes. A adesão das células ao substrato influencia na morfologia, na proliferação e na viabilidade celular. Neste trabalho, foram avaliadas adesão, proliferação e viabilidade de fibroblastos de camundongo, linhagem L929, em suporte biopolimérico. Utilizaram-se membranas de celulose bacteriana como substrato para a avaliação in vitro. As células foram cultivadas sobre essas membranas em meio Dulbecco’s Modified Eagle Medium (DMEM), suplementado com 10% de Soro Bovino Fetal (SBF), a 37°C, contendo 5% CO2. Para monitorar e avaliar o comportamento dessas células em distintos tempos de cultivos nas membranas, escolheram-se diferentes parâmetros celulares. Com base nessa experiência, observaram-se diferenças morfológicas significativas nas células. Os resultados evidenciaram boa adesão, crescimento, proliferação e viabilidade das células nas membranas utilizadas.

The present study investigated the antioxidant properties of Cyathea phalerata Mart. (Cyatheaceae) using in vitro and in vivo assays. The in vitro antioxidant potential of the crude extract (CE), precipitate (PPT), aqueous fraction (AQF), n-butanolic fraction (BUF) and ethyl acetate fraction (EAF) from C. phalerata was evaluated through the scavenging of diphenyl-1-picryl-hydrazyl-hydrate (DPPH), superoxide anion (O 2 • − ) (nitroblue tetrazolium assay) and hydroxyl radicals (OH • ) (deoxyribose assay), and lipid peroxidation in rat liver homogenate. In these assays, it was observed that EAF had marked antioxidant potential, especially as a scavenger of the OH • radical and in inhibiting lipid peroxidation. The in vivo evaluation of oxidative stress (DNA fragmentation, membrane lipoperoxidation and carbonyl protein formation) and the antioxidant defenses (concentration of reduced glutathione, as well as catalase and glutathione S-transferase activities) were measured in mice pre-treated with EAF (10, 30 or 100 mg/kg, orally) and later exposed to carbon tetrachloride (CCl 4 ). The EAF decreased thiobarbituric acid reactive substances levels, DNA damage and carbonyl protein contents, and increased catalase and glutathione S-transferase activities. Based on these results, it is concluded that the EAF from C. phalerata protects liver from oxidative stress induced by CCl 4 in mice and these effects are probably related to the antioxidant activity associated with the free radical scavenging property of this fraction. Cyathea phalerata Mart. (Cyatheaceae) is a tree fern that grows in the tropical and subtropical areas of Brazil and is commonly known as 'xaxim'. In folk medicine, its stem pith is used to treat several inflammatory diseases and the alco- hol extract of the pith is used for the treatment of varicose veins and hemorrhoids. In phytochemical studies of Cyathea genus, several classes of compounds were identified such as fernene, filicene and hopane triterpenes (1,2), phenolic acids (coumaric and caffeic), protocatechuic acids and flavonoids, mainly kaempferol glycosides (3-5). In a recent study, Pizzolatti et al . (6) isolated the cyathenosin A, a spiropyranosil derivative of protocatechuic acid, from the stem pith of C. phalerata . Studies on the pharmacological effects of C. phalerata are still limited. However, recently, Cazarolli et al . (7) demonstrated that the flavonoid, kaempferol-3- neohesperidoside, isolated from C. phalerata , has a hypogly- caemic effect in diabetes induced by alloxan in rats. Flavonoids exhibit a wide range of biological effects, includ- ing antibacterial, anti-inflammatory, anti-allergic, hepato- protective, antithrombotic, antiviral, anticarcinogenic and vasodilatory actions; many of these biological functions have been attributed to the free radical scavenging and antioxidant activity of these compounds (8-10). Oxidative stress plays an important role in the pathogenesis of several human pathologies, including ischaemia and reperfusion injury, atherosclerosis, neurodegenerative diseases and cancer (11). The excess of reactive oxygen species (ROS) can damage cellular lipids, proteins or DNA, thereby inhibiting their normal function (12). Thus, oxidative stress has been implicated in a number of human diseases as well as in the ageing process (11). Owing to the relative inefficiency of our endogenous defence systems and the existence of some pathophysiological situations (cigarette smoke, air pollutants, ultraviolet radiation, inflammation, ischaemia/ reperfusion, etc.) in which ROS are produced in excess and at the wrong time and place, dietary antioxidants are needed to diminish the cumulative effects of oxidative damage over the life span (13). In this regard, there has been a great deal of interest in the screening and characterization of novel, potentially therapeutic herbal products. Therefore, the aim of the present study was to investigate the antioxidant activity ( in vitro and in vivo ) of the crude extract and fractions obtained from C. phalerata .

A polysaccharide (Sarg) extracted from the brown marine alga Sargassum stenophyllum was studied for its antivasculogenic effects in both in vivo and in vitro assays, as well as for its capacity to modify embryonic morphogenetic processes endogenously regulated by bFGF, a well-known angiogenic stimulator. The antivasculogenic activity of Sarg (6-1500 microg/implant) was evaluated in a chick yolk sac membrane assay and the embryonic morphogenesis was measured as the percentage cephalic length. Sarg alone (96-1500 microg/implant) and co-administered with hydrocortisone (HC; 156 microg/implant) decreased the vitelline vessel number by 23-100% and 54-100% respectively. The polysaccharide potentiated the antivasculogenic effect of HC (42% inhibition). Basic fibroblast growth factor-stimulated vasculogenesis (141% of vessels as compared to control) was partially reversed by Sarg. The treatment with Sarg also decreased the percentage cephalic length of 3.5- and 4-day chick embryos (as cultured in vivo and in vitro, respectively), uncoupled from any impairment in the body shape or embryotoxic effect. Due to polyanionic characteristics of Sarg, which are similar to those seen in the heparin molecule, we suggest that this polysaccharide should modulate the activity of heparin-binding vascular growth factors (such as bFGF, which also acts as a morphogen) mimetically interfering with heparan sulfate proteoglycans during microvessel formation.

Plinia cauliflora (jaboticaba) is a native fruit tree from Brazilian rainforest widely used in popular medicine to prevent diarrhea, asthma, and infections. Studies have shown that the major therapeutic potential of jaboticaba fruits is on its peel, a rich source of anthocyanins. These secondary metabolites have well-known antioxidant and anti-inflammatory activities and have been claimed to be effective to treat diabetes, cancer, cardiovascular diseases, and stroke. This chapter describes a series of methodologies to evaluate important in vitro biological activities like cytotoxicity, proliferation, and migration of a hydroalcoholic extract of jaboticaba peel on mouse fibroblast L929 line. Assays to assess total phenolic, flavonoid, and anthocyanin contents and antioxidant activities are described as well.

Wilbrandia ebracteata (WE), a Brazilian medicinal plant used in folk medicine for the treatment of rheumatic diseases, displays anti-inflammatory properties and constitutes a rich source of cucurbitacins and cucurbitacin-related compounds. The current study investigated the potential anti-inflammatory properties of Dihydrocucurbitacin B (DHCB), a cucurbitacin-derived compound isolated from roots of WE, in some in vivo and in vitro experimental models. Intraperitoneal treatment of mice with DHCB reduced both carrageenan-induced paw edema (0.3, 1 and 3 mg/kg caused inhibitions of 26, 44 and 56 % at 2 h after stimulation, respectively) and pleurisy (10 mg/kg inhibited leukocyte numbers and LTB(4) levels in the pleural fluid by 51 and 75% at 6 h after cavity challenge, respectively). In vitro, DHCB (up to 10 microg/mL) failed to modify LTB(4) production by human neutrophils or PGE(2) production by COS-7 cells transfected with COX-1, but PGE(2) production by COX-2 transfected COS-7 cells was markedly inhibited (by 72%). The levels of COX-1 or COX-2 proteins in IL-1alpha-stimulated NIH3T3 cells were unaffected by DHCB. The results corroborate the potential anti-inflammatory properties ascribed to W. ebracteata Cogn. in folk medicine and suggest that they might be attributed, at least in part, to the capacity of one of this plants main constituents, DHCB, to inhibit COX-2 activity (but not its expression) during inflammation.

O estudo das interações entre células e seu substrato na engenharia de tecidos é de grande importância para determinação das propriedades biológicas dos implantes. A adesão das células ao substrato influencia na morfologia, na proliferação e na viabilidade celular. Neste trabalho, foram avaliadas adesão, proliferação e viabilidade de fibroblastos de camundongo, linhagem L929, em suporte biopolimérico. Utilizaram-se membranas de celulose bacteriana como substrato para a avaliação in vitro. As células foram cultivadas sobre essas membranas em meio Dulbecco’s Modified Eagle Medium (DMEM), suplementado com 10% de Soro Bovino Fetal (SBF), a 37°C, contendo 5% CO2. Para monitorar e avaliar o comportamento dessas células em distintos tempos de cultivos nas membranas, escolheram-se diferentes parâmetros celulares. Com base nessa experiência, observaram-se diferenças morfológicas significativas nas células. Os resultados evidenciaram boa adesão, crescimento, proliferação e viabilidade das células nas membranas utilizadas.

A identificação, extração, isolamento e caracterização de princípios ativos vegetais que modulam a viabilidade celular são de grande interesse clínico e farmacológico. Testes fitoquímicos têm demonstrado a presença de vários compostos oriundos dos metabolismos primário e secundário da Aloe vera L. A aloína é uma antraquinona isolada do parênquima clorofiliano da A. vera L que, sabe-se, apresenta atividade biológica. A atividade antitumoral da aloína e do extrato do parênquima clorofiliano foi avaliada, in vitro, com a utilização de células de melanoma de camundongo da linhagem B16-F10. Nessa análise, células incubadas em atmosfera com 5% de CO2 foram tratadas em diferentes concentrações de aloína e de extrato do parênquima, a 37ºC. A aloína e o extrato alteraram a estabilidade celular, exercendo efeito modulador sobre a viabilidade das células tumorais. Os dados experimentais foram representados por meio de um modelo matemático. Neste estudo, verificou-se que o extrato do parênquima clorofiliano é 2,3 vezes mais tóxico que a aloína.

The formation of embryonic blood vessels, defined as vasculogenesis, is a complex morphogenetic process ultimately related to tubulogenesis, carried out from in situ differentiation of mesoderm-recruited or proliferated progenitor endothelial cells (angioblasts) to endothelial cells for structuring a primary vascular plexus. Subse‐ quent events involving apoptosis versus cell survival (remodeling) in the vessel network stabilizes the primordial microvasculature, which through the angiogenesis process yields new capillaries by sprouting from the preexisting ones. Methylxan‐ thinic alkaloids such as caffeine (compounds present in a number of beverages consumed worldwide) exert some well-known effects upon heart and other cardio‐ vascular structures, in part, by negatively interplaying with phosphodiesterase (PDEs) enzymes. Once caffeine as well as Ilex paraguariensis (yerba mate) infusion extract have shown to enhance the vessel formation (vasculogenesis and angiogene‐ sis), we discuss the impact afforded by I. paraguariensis constituents on the (PDEsrelated) quantities and stability of Protein kinase A (PKA) and Protein kinase C (PKC) enzymes. Besides, the text reflects on a suggested dual roles displayed by PKA and PKC enzymatic pathways in the developmental angiogenic events.

In a previous study, we demonstrated the antinociceptive effect of 63SF, a proanthocyanidin-rich fraction obtained from Croton celtidifolius barks, in chemical and thermal behavioural models of pain in mice. The current study now investigate the possible mechanisms underlying the antinociceptive activity of 63SF in the formalin test, by using drugs which interfere with systems that are implicated in descending control of nociception. The antinociceptive effect of 63SF (11 mg/kg, i.p., given 30 min prior to 2.5% formalin) was not altered by pre-treatment of animals 45-50 min beforehand with either prazosin (alpha(1)-adrenergic antagonist; 0.15 mg/kg, i.p.), yohimbine (alpha(2)-adrenergic antagonist; 0.15 mg/kg, i.p.), ketanserin (5-HT(2A)-receptor antagonist; 1.0 mg/kg, i.p.), or l-arginine (substrate for NO synthase, 600 mg/kg, i.p.). On the other hand, treatment with sulpiride, an antagonist of dopaminergic D(2)-receptors (1.0 mg/kg, i.p., 45 min of pre-treatment), reversed the antinociceptive activity of 63SF. Pre-treatment of animals with reserpine (5 mg/kg, i.p., 24 h beforehand) did not alter the antinociceptive effect of 63SF. The current results support the view that the 63SF exerts antinociceptive effects by enhancing the activity of descending control, possibly by direct stimulation of dopaminergic D(2) receptors.

Uncaria tomentosa (Willd.) DC (Rubiaceae) is a vine that grows in the Amazon rainforest. Its bark decoctions are used by Peruvian Indians to treat several diseases. Chemically, it consists mainly of oxindole alkaloids. An industrial fraction of U. tomentosa (UT fraction), containing 95% oxindole alkaloids, was used in this study in order to characterize its antinociceptive activity in chemical (acetic acid-induced abdominal writhing, formalin and capsaicin tests) and thermal (tail-flick and hot-plate tests) models of nociception in mice. UT fraction given by the i.p. route dose-dependently suppressed the behavioural response to the chemical stimuli in the models indicated and increased latencies in the thermal stimuli models. The antinociception caused by UT fraction in the formalin test was significantly attenuated by i.p. treatment of mice with ketanserin (5-HT2 receptor antagonist), but was not affected by naltrexone (opioid receptor antagonist), atropine (a nonselective muscarinic antagonist), l-arginine (precursor of nitric oxide), prazosin (alpha1-adrenoceptor antagonist), yohimbine (alpha2-adrenoceptor antagonist), and reserpine (a monoamine depleter). Together, these results indicate that UT fraction produces dose-related antinociception in several models of chemical and thermal pain through mechanisms that involve an interaction with 5-HT2 receptors.

A number of studies suggest that moderate consumption of red wine may be more effective than other alcoholic beverages in decreasing the risk of coronary heart disease (CAD). In this study, we investigated the effect of a crude extract (CE), as well as an ethyl acetate fraction (EAF) obtained from a Brazilian red wine in the mesenteric arterial bed (MAB) from rats. Our results showed that after the tonus of MAB was increased with phenylephrine (PE), increasing concentrations of CE induced a concentration-dependent relaxation; moreover, EAF was more potent in relaxing the MAB when compared with CE. In vessels depolarized with KCl (80 mM) or treated with the Na(+)/K(+)-ATPase pump inhibitor, ouabain (OUA; 100 microM), or with the K(+) channel blockers: barium (BaCl(2), 100 microM) and tetraethylammonium (TEA; 500 microM), the effect of EAF was significantly reduced. However, this effect was not altered by the ATP-dependent K(+) (K(ATP)) channel blocker, glibenclamide (GLI; 100 microM) as well as Charybdotoxin (ChTx 10 nM), a nonselective inhibitor of K(Ca) channels of large and intermediate conductance plus Apamin (Apamin 100 nM), a specific inhibitor of K(Ca) channels of small conductance. The residual vasodilator effect of EAF observed in vessels pretreated with L-NOARG (100 microM), 1H-[1,2,4,] oxadiazolo[4,3-alfa]quinoxalin, ODQ (10 microM) or KCl (80 mM), given separately, was reduced by the administration of KCl (40 mM) plus L-NOARG (100 microM). The present study demonstrates that the vasodilator effect of EAF is partially dependent upon membrane hyperpolarization in combination with nitric oxide (NO) release.

The potential antiangiogenic and antitumoral properties of SargA, a polysaccharide extracted from the brown marine alga Sargassum stenophyllum, were studied in assays carried out in chick embryos and mice. Gelfoam plugs containing SargA (2-1500 microg/plug) implanted in vivo into fertilized 6-day-old chicken eggs induced dose-related antiangiogenic activity in the chorioallantoic membrane (CAM). By day 8, the highest dose of SargA alone decreased the vessel number in the CAM by 64%, but coadministered with hydrocortisone (156 microg/plug, which alone caused 30% inhibition) failed to potentiate its antiangiogenic effect. Combined with basic fibroblast growth factor (50 ng/plug), SargA (1500 microg/plug) abolished angiogenesis stimulated by this factor in both chick embryo CAM and in subcutaneous (s.c.) Gelfoam plugs implanted in the dorsal skin of Swiss mice (measured as plug hemoglobin content). Repeated s.c. injections of SargA (1.5 or 150 microg per animal per day for 3 days) close to B16F10 melanoma cell tumors in the dorsal skin of mice markedly decreased tumor growth in a dose-related fashion (by 40% and 80% at 2 weeks after the first injection, respectively), without evident signs of toxicity. SargA caused graded inhibitions of migration and viability of cultured B16F10 cells and also displayed antithrombotic activity in human plasma (5 mg/ml increased thrombin time 2.5-fold relative to saline). Thus, SargA exhibits pronounced antiangiogenic as well as antitumoral properties. Although the latter action of SargA might be related to the inhibition of angiogenesis, the polysaccharide also exerts cytotoxic effects on tumor cells. Because of its chemical characteristics and polyanionic constituents, we postulate that the polysaccharide SargA might modulate the activity of heparin-binding angiogenic growth factors.

Pretreatment of mice with Ro5-4864 or PK11195 inhibited the first- and second-phase responses in the formalin test and this effect was significantly reversed by aminoglutethimide, an inhibitor of pregnenolone synthesis, suggesting that the antinociceptive effect of the peripheral-type benzodiazepine receptor ligands is dependent on steroid formation. Doses of Ro5-4864 that did not produce an antinociceptive effect when injected by the intraperitoneal route presented an analgesic effect, if infected by the intracerebroventricular, intrathecal or intraplantar routes. PK11195 pretreatments with intrathecal, intracerebroventricular or intraplantar doses had no effect in the formalin test. These results suggest that the antinociceptive effect of Ro5-4864 reflects the influence of this ligand on steroid production not only in many nonneuronal peripheral tissues but also in the nervous system, while the antinociceptive action of PK11195 may be due to the stimulation of steroid synthesis only in nonnervous tissues.

Wilbrandia ebracteata is a medicinal plant from South America used in folk medicine for the treatment of chronic rheumatic diseases. We have shown that the high performance liquid chromatography-characterized (HPLC) dichloromethane fraction isolated from Wilbrandia ebracteata (WEDC) inhibits the parameters observed in experimental models of inflammation in vivo and in vitro. In the present study, we extend our previous observations on the analgesic effects of WEDC by investigating its actions using the hot plate test and zymosan-induced writhing test in mice, as well as zymosan-induced arthritis in rats evaluating articular inflammatory pain, cell migration and determination of NO release into the joint exudate. The effect of WEDC on the activity of COX-1 and COX-2 in vitro and its ulcerogenic capacity in vivo were also investigated. The oral treatment of the animals with WEDC (1-10 mg/kg) produced a significant, dose-dependent reduction of articular incapacitation and abdominal contortions in the writhing test. The same effect was not observed in the hot plate and rota-rod tests. WEDC also reduced nitrite release into the zymosan-inflamed joints. In the evaluation of COX activity, we observed that WEDC was able to selectively inhibit COX-2 but not COX-1 activity in COS-7 cells. Moreover, WEDC treatment did not show gastrointestinal toxicity. Our data confirm the anti-nociceptive activities of the WEDC and indicate that this effect could be associated with inhibition of cyclooxygenase-2 (COX-2) and nitric oxide release. The effects could be attributed to cucurbitacins since several of these were isolated from the WEDC.

Croton celtidifolius Baill commonly known as "sangue-de-adave" is a tree found in the Atlantic Forest of south of Brazil, mainly in Santa Catarina. The bark and leaf infusions of this medicinal plant have been popularly used for the treatment of inflammatory diseases. In this study we evaluated the anti-inflammatory and antioxidant properties of crude extract (CE), aqueous fraction (AqF), ethyl acetate fraction (EAF), butanolic fraction (BuF) and catechin, gallocatechin and sub-fractions, 19SF, 35SF and 63SF that contained a mixture of proanthocyanidins and were derived from the EAF fraction. The CE, AqF, EAF, BuF, catechin and sub-fractions 35SF and 63SF reduced paw edema induced by carrageenan. The CE, fractions, sub-fractions and isolated compounds showed antioxidant properties in vitro, all were able to scavenge superoxide anions at a concentration of 100 microg ml(-1). The EAF, catechin and gallocatechin were most effective in the deoxyribose assay, IC50 0.69 (0.44-1.06), 0.20 (0.11-0.39), 0.55 (0.28-1.08) microg x ml(-1) respectively. The CE and other fractions and sub-fractions inhibited deoxyribose degradation up to 1 microg x ml(-1). In the hydrophobic system only AqF did not show lipid peroxidation inhibition. The CE, other fractions, sub-fractions and isolated compounds inhibited lipidid peroxidation only at a concentration of 100 microg x ml(-1). In summary, this study demonstrates that Croton celtidifolius bark has significant anti-inflammatory and antioxidant activity.

We investigated the antioxidant activity of phenylpropionic acids--caffeic (CAF), ferulic (FER), para-coumaric (COU) and cinnamic (CIN)--and phenolic acids and related compounds--gallic (GAL), methyl gallate (meGAL), vanillic (VAN) and gentisic (GEN)--using visible spectroscopy, inhibition of nitroblue tetrazolium (NBT) reduction, and electrochemical methods including cyclic voltammetry and potentiometry. In the spectroscopic assays, only CAF, GAL and meGAL were able to inhibit NBT reduction. The same compounds showed the lowest oxidation potentials (Epa) and the highest redox potentials deltaE) in the cyclic voltammetric and potentiometric studies, respectively. In addition, it was observed that the greater the number of hydroxyls linked to the aromatic ring, the greater was the antioxidant activity of the analysed compounds. The correlations of Spermann--used to compare the methods between themselves and the methods with the relationship structure-antioxidant activity--were r = -0.9762 for the cyclic voltammetric-potentiometric methods. r = 0.8333 for the inhibition of NBT reduction-potentiometric methods and r = -0.8095 for the inhibition of NBT reduction-cyclic voltammetric methods. The correlations for cyclic voltammetric, potentiometric and inhibition of NBT reduction methods-number of hydroxyls linked to the aromatic ring were r = -0.9636, 0.9636 and 0.9142, respectively. These findings indicate that the electrochemical methods together with spectroscopic studies are a good tool to evaluate the antioxidant activity of substances.

In vivo treatment of mice with peripheral benzodiazepine receptor ligands exerts an inhibitory effect on the inflammatory response in two models of acute inflammation. In the first model, pretreatment of the animals (24 h) with 1-(2-chlorophenyl)-N-methyl-N(1-methylpropyl)-3-isoquinoline carboxamide (PK11195) and 7-chloro-5-(4-Chlorophenyl)-1, 3-dihydro-1-methyl-2-H-1,4-benzodiazepin-2 (Ro5-4864), at different doses (0.00001-10 mg/kg, i.p.) dose dependently inhibited the formation of mouse paw oedema induced by carrageenan with mean ID(50s) of 0.009 (95% confidence limits=0.0076-0.013) and 0.04 (95% confidence limits=0.025-0.0086) mg/kg, respectively. Both ligands (0. 1 mg/kg, i.p.) inhibited in the same way the mouse paw oedema induced by carrageenan in animals with and without adrenal glands. PK11195 and Ro5-4864 (0.1 mg/kg, i.p.) inhibited the mouse paw oedema induced by several inflammatory mediators. In the second model, the pretreatment (24 h) with peripheral benzodiazepine receptor ligands (0.1 mg/kg, i.p.) exerted an inhibitory effect on neutrophil influx and produce a marked inhibition of carrageenan-produced interleukin-13 and interleukin-6 in pleural exudation. Our results extend previous findings that peripheral benzodiazepine receptor is involved in the inflammatory response, and suggest that this action may be linked to the action of different inflammatory mediators, probably mainly by the inhibition of the release of pro-inflammatory cytokines.

Wilbrandia ebracteata Cogn. (Cucurbitaceae) is commonly known in Brazil as “Taiuia”. The roots are employed in folk medicine for the treatment of several diseases, such as rheumatic disease. This study has evaluated the anti-inflammatory action of dicloromethane fraction (F-DCM), purified fraction (PFIII) and Cucurbitacin B extracted from crude extract of W. ebracteata in experimental models in vivo . The F-DCM (0.3 to 10 mg.kg −1 , i.p. or 3 to 30 mg.kg −1 p.o.) produced significant but not dose-dependent inhibition of the carrageenan-induced cell influx and exsudate leakage in the pleural cavity of mice. The F-DCM 0.01 to 10 mg.kg −1 , i.p. or 0.1 to 10 mg.kg −1 p.o.) decreased the levels of PGE 2 in the exsudate leakage induced by carrageenan in the pleural cavity after 4 h with a calculated ID 50 of 0.01 (0.002–0.09, i.p.) and 0.29 (0.05–1.45, p.o.) mg.kg −1 . The PFIII (3 mg.kg −1 , i.p.) inhibited 80% of cell migration (1.50 ± 0.09 × 10 6 cells/cavity) and exsudate leakage by about 50% (3.09 ± 0.71 μg ml ) in relation to the control group. Cucurbitacin B (0.1 mg.kg −1 , i.p.), the main compound of PFIII, reduced significantly the levels of PGE 2 in the exsudate leakage by 40.7% (10.41 ± 2.67 ng.ml −1 ). These data show that the active principle(s) present in the F-DCM of W. ebracteata elicited pronounced anti-inflammatory effects when assessed by i.p. or p.o. routes, as well as PFIII. The F-DCM was also able to prevent PGE 2 formation in exsudate leakage induced by carrageenan, as well as Cucurbitacin B, its active principle. These results indicate that the anti-inflammatory activity of Wilbrandia ebracteata can be related with the inhibition of the production of PGE 2 .

Elevated levels of oxidized low density lipoprotein (oxLDL) are considered to be one of the major risk factors for atherosclerosis and cardiovascular morbidity. The early stages of atherosclerosis are initiated by the accumulation of oxLDL and the induction of toxic effects on endothelial cells, resulting in endothelial dysfunction. The aim of this study was to investigate how diphenyl diselenide (DD), an organoselenium compound, protect vascular endothelial cells against the toxic effects of oxLDL in vitro. Our data showed that the treatment of bovine endothelial aortic cells (BAEC) with DD (0.1-1 μM) for 24 h protected from oxLDL-induced reactive species (RS) production and reduced glutathione (GSH) depletion. Moreover, DD (1 μM) per se improved the maximal mitochondrial respiratory capacity and prevented oxLDL-induced mitochondrial damage. In addition, DD could prevent apoptosis induced by oxLDL in BAEC. Results from this study may provide insight into a possible molecular mechanism underlying DD suppression of oxLDL-mediated vascular endothelial dysfunction.

Electrospun materials have been widely explored for biomedical applications because of their advantageous characteristics, i.e., tridimensional nanofibrous structure with high surface-to-volume ratio, high porosity, and pore interconnectivity. Furthermore, considering the similarities between the nanofiber networks and the extracellular matrix (ECM), as well as the accepted role of changes in ECM for hernia repair, electrospun polymer fiber assemblies have emerged as potential materials for incisional hernia repair. In this work, we describe the application of electrospun non-absorbable mats based on poly(ethylene terephthalate) (PET) in the repair of abdominal defects, comparing the performance of these meshes with that of a commercial polypropylene mesh and a multifilament PET mesh. PET and PET/chitosan electrospun meshes revealed good performance during incisional hernia surgery, post-operative period, and no evidence of intestinal adhesion was found. The electrospun meshes were flexible with high suture retention, showing tensile strengths of 3 MPa and breaking strains of 8-33%. Nevertheless, a significant foreign body reaction (FBR) was observed in animals treated with the nanofibrous materials. Animals implanted with PET and PET/chitosan electrospun meshes (fiber diameter of 0.71 ± 0.28 µm and 3.01 ± 0.72 µm, respectively) showed, respectively, foreign body granuloma formation, averaging 4.2-fold and 7.4-fold greater than the control commercial mesh group (Marlex). Many foreign body giant cells (FBGC) involving nanofiber pieces were also found in the PET and PET/chitosan groups (11.9 and 19.3 times more FBGC than control, respectively). In contrast, no important FBR was observed for PET microfibers (fiber diameter = 18.9 ± 0.21 µm). Therefore, we suggest that the reduced dimension and the high surface-to-volume ratio of the electrospun fibers caused the FBR reaction, pointing out the need for further studies to elucidate the mechanisms underlying interactions between cells/tissues and nanofibrous materials in order to gain a better understanding of the implantation risks associated with nanostructured biomaterials.

Objectives In this study, we evaluated the effect of the proanthocyanidins-rich fraction (PRF) obtained from Croton celtidifolius bark in an experimental animal model of spinal cord injury and cell death induced by glutamate. Methods Experiments were conducted using adult male Wistar rats (10 weeks old and weighing 270–300g). Experimental groups were randomly allocated into the following groups: spinal cord injury (SCI) + vehicle group: rats were subjected to SCI plus intraperitoneal administration of vehicle (saline 10 ml/kg); SCI + PRF: rats were subjected to SCI plus intraperitoneal administration of PRF (10 mg/kg) at 1 and 6 h after injury and sham operated. Key findings The treatment with the proanthocyanidin-rich fraction significantly improved not only motor recovery and grip force but also H2O2 or glutamate-induced cell death and reactive oxygen species generation induced by glutamate in dorsal root ganglion cells. In this study we demonstrate that the neuroprotective effect triggered by the proanthocyanidins-rich fraction appears to be mediated in part by the inhibition of N-methyl-D-aspartate-type glutamate receptors. Conclusions Taken together, our results demonstrate that PRF treatment ameliorates spinal cord injury and glutamatergic excitotoxicity and could have a potential therapeutic use.

Objectives The present work aimed to investigate the effect of (PhSe)2 on cardiovascular age-related oxidative stress in hypercholesterolemic mice. Methods To this end, LDL receptor knockout (LDLr−/−) mice, 3 months (young adult) and 12 months (middle-aged) old, were orally treated with (PhSe)2. Key findings Hypercholesterolemia, regardless of age, impaired the mitochondrial antioxidant defence in the cardiac tissue, which was characterized by a decline in mitochondrial aortic glutathione (GSH) levels and increased reactive oxygen species production in the heart. (PhSe)2 treatment improved GSH levels, thioredoxin reductase (TRxR) and GSH reductase (GR) activity, and decreased malondialdehyde levels in the heart of young adult LDLr−/− mice. Moreover, (PhSe)2 increased GPx activity in both age groups, and GR activity in the aorta of middle-aged LDLr−/− mice. Conclusions Therefore, (PhSe)2 enhances the antioxidant defences in the cardiovascular system of LDLr−/− mice, which could explain its success as an anti-atherogenic compound.

Recent studies have indicated a causal link between high dietary cholesterol intake and brain oxidative stress. In particular, we have previously shown a positive correlation between elevated plasma cholesterol levels, cortico-cerebral oxidative stress and mitochondrial dysfunction in low density lipoprotein receptor knockout (LDLr(-/-)) mice, a mouse model of familial hypercholesterolemia. Here we show that the organoselenium compound diphenyl diselenide (PhSe)2 (1 mg/kg; o.g., once a day for 30 days) significantly blunted the cortico-cerebral oxidative stress and mitochondrial dysfunction induced by a hypercholesterolemic diet in LDLr(-/-) mice. (PhSe)2 effectively prevented the inhibition of complex I and II activities, significantly increased the reduced glutathione (GSH) content and reduced lipoperoxidation in the cerebral cortex of hypercholesterolemic LDLr(-/-) mice. Overall, (PhSe)2 may be a promising molecule to protect against hypercholesterolemia-induced effects on the central nervous system, in addition to its already demonstrated antiatherogenic effects.

It is generally accepted that the ryanodine receptor and the inositol 1,4,5-trisphosphate receptor play major roles in the complex mechanisms by which agonists increase intracellular Ca2+ concentration. In these mechanisms, the endoplasmic reticulum Ca(2+)-ATPase has been attributed an accessory role of refilling the intracellular Ca2+ store. In the present study, the activity of the microsomal Ca(2+)-ATPase of bovine adrenal cortex was investigated. We show that the Ca(2+)-pumping activity of the Ca(2+)-ATPase is related to the ADP/ATP ratio. Our results also show that a brisk increase of the ADP/ATP ratio upon addition of exogenous ADP triggered a rapid release of Ca2+ from preloaded microsomes. ADP released Ca2+ in a dose-dependent manner with an EC50 of 2.98 +/- 0.78 mM. ADP-induced Ca2+ release was not prevented by heparin, ruling out the participation of the inositol 1,4,5-trisphosphate receptor. ADP-induced Ca2+ release could not be attributed to the mere inhibition of the Ca(2+)-ATPase, since the rate of ADP-induced Ca2+ release was 20 times faster than the rate of Ca2+ release induced by a maximal concentration of thapsigargin (2 microM). ADP-induced Ca2+ release experiments performed in the presence of [32P]PO4 revealed a concomitant production of [32P]ATP. ADP-induced [32P]ATP production was dose-dependent, with an EC50 of 5.50 +/- 0.70 mM. ADP-induced [32P]ATP production was prevented by ionomycin (10 microM) and by high concentrations of extramicrosomal Ca2+. These results demonstrate that the microsomal Ca(2+)-ATPase of adrenal cortex possesses a bidirectional activity that depends on ADP concentrations, the Ca2+ gradient across the microsomal membrane, and probably also ATP concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

The purpose of this study was to evaluate hybrid poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/chitosan nanofibrous mats as scaffolds for skin engineering. In vitro studies were carried out to test the potential of the scaffolds for fibroblasts adhesion, viability, and proliferation (L929 cell line). The in vivo performance was also studied in a full-thickness wound healing model. PHBV/chitosan 4:1 (w/w) exhibited a higher in vitro biocompatibility and a better ability for cell adhesion and growth, compared to PHBV/chitosan 2:3 (w/w). The in vivo assay also revealed the better performance of this scaffold, improving the wound healing process in rats.

Objectives This paper aims to evaluate the anti-tumour properties of elatol, a compound (sesquiterpene) isolated from algae Laurencia microcladia. Methods In-vitro and in-vivo anti-tumour properties of elatol were investigated using: MTT assays to assess the cytotoxic effects; flow cytometry analysis to examine the cell cycle and apoptosis; Western blot analysis for determination of the expression of cell cycle and apoptosis proteins; and study of in-vivo tumour growth in mice (C57Bl6 mice bearing B16F10 cells). Key findings Elatol exhibited a cytotoxic effect, at least in part, by inducing cell cycle arrest in the G1 and the sub-G1 phases, leading cells to apoptosis. Western blot analysis demonstrated that elatol reduced the expression of cyclin-D1, cyclin-E, cyclin-dependent kinase (cdk)2 and cdk4. A decrease in bcl-xl and an increase in bak, caspase-9 and p53 expression was also observed. In the in-vivo experiment, treatment with elatol was able to reduce tumour growth in C57Bl6 mice. Conclusions Elatol promotes a delay in the cell cycle, probably in the G1/S transition, activating the apoptotic process and this could be responsible, at least in part, for the in-vivo effects observed. Taken together, the in-vitro and in-vivo experiments suggested that elatol has anti-tumour properties. Further studies should be conducted to clarify the mechanism of action.

Microporous, non-woven fibrous scaffolds made of poly(ethylene terephthalate) and chitosan were produced by electrospinning. Fiber morphology, diameter, pore size, and wettability were manipulated by varying the chemical composition of the electrospinning solution, i.e. chitosan concentration and molecular weight, and by post-electrospinning treatment with glutaraldehyde. In vitro studies were conducted using a fibroblast cell line toward a comprehensive understanding of how scaffolds characteristics can modulate the cell behavior, i.e. viability, adhesion, proliferation, extracellular matrix secretion, and three-dimensional colonization. Substantial differences were found as a result of scaffold morphological changes. Higher levels of adhesion, spreading, and superficial proliferation were achieved for scaffolds with smaller fiber and pore diameters while cell penetration and internal colonization were enhanced for scaffolds with larger pores. Additionally, the available area for cell adhesion, which is related to fiber and pore size, was a crucial factor for the viability of L929 cells. This paper provides significant insights for the development and optimization of electrospun scaffolds toward an improved biological performance.

The aim of this study was to evaluate the effects of green tea extract (GTE) administration on vascular reactivity and atherosclerosis progression in low-density lipoprotein receptor knockout mice. We hypothesized that GTE intake may ameliorate atherosclerosis by improving endothelial dysfunction. Animals (n = 12 per group) were fed a hypercholesterolemic diet and received either water or GTE at a dose of 50, 100, or 300 mg/kg once a day by gavage (100 μL/10 g weight). After 4 weeks, atherosclerosis extension and vascular reactivity were evaluated in the aorta, and the levels of lipids, monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor α were measured in the plasma. Administration of GTE at a dose of 50 mg/kg significantly decreased the area of atherosclerotic lesions by 35%, improved the vascular reactivity in the isolated thoracic aorta, and lowered the plasma levels of both MCP-1 and triglycerides. Delivery of 100 mg/kg of GTE only promoted vasocontraction and vasorelaxation (P.05), whereas a dose of 300 mg/kg was ineffective. Maximum contraction and relaxation negatively correlated with the lesion area (r = -0.755 and -0.767, respectively), whereas the plasma levels of MCP-1 and triglycerides positively correlated with plaque size (r = 0.549 and 0.421, respectively). In summary, our results supported the hypothesis that administration of GTE at low doses may contribute to a decrease in atherosclerosis progression by reversing endothelial dysfunction.

Convergent epidemiological, clinical, and experimental findings indicate that hypercholesterolemia contributes to the onset of Alzheimer's disease (AD)-like dementia, but the exact underlying mechanisms remains unknown. In this study, we evaluated the cognitive performance of mice submitted to a model of hypercholesterolemia, as well as its relationship with mitochondrial dysfunction and oxidative stress, two key events involved in AD pathogenesis. Wild-type C57bl/6 or low density lipoprotein receptor (LDLr)-deficient mice were fed with either standard or cholesterol-enriched diet for a 4-week period and tested for spatial learning and memory in the object location task. LDLr⁻/⁻ mice displayed spatial learning and memory impairments regardless of diet. Moreover, LDLr⁻/⁻ mice fed cholesterol-enriched diet presented a significant decrease in the mitochondrial complexes I and II activities in the cerebral cortex, which were negatively correlated with respective blood cholesterol levels. Additionally, hypercholesterolemic LDLr⁻/⁻ mice presented a significant decrease in glutathione levels, about 40% increase in the thiobarbituric acid-reactive substances levels, as well as an imbalance between the peroxide-removing-related enzymes glutathione peroxidase/glutathione reductase activities in the cerebral cortex. These findings indicate a significant relationship between hypercholesterolemia, cognitive impairment, and cortico-cerebral mitochondrial dysfunctional/oxidative stress. Because of the involvement of such alterations in AD patients, our data render this mouse model of hypercholesterolemia a useful approach to comprehend the molecular events mediating AD pathogenesis.

Novel hybrid fibrous membranes with potential application on the biomedical field were successfully developed via electrospinning of blend solutions of two biocompatible and biodegradable polymers, poly (3-hydroxybutyrate-co-hydroxyvalerate) [PHBV] and chitosan. The effect of solvent, using different proportions of trifluoracetic acid (TFA) and 1,1,1,3,3,3-hexafluoro-2-isopropanol (HFIP), PHBV/chitosan ratio, and chitosan molecular weight on solution spinnability, fiber morphology and size, and in vitro degradation were investigated. Continuous nanofiber structures were obtained from pristine PHBV to a PHBV/chitosan ratio of 2:3 (w/w), at 10% (w/v) total polymer concentration. In general, main fiber average diameters increased as chitosan content and molecular weight increased and decreased with the decrease of HFIP content in the solvent. In vitro dissolution tests revealed that the hybrid fibers show much higher degradation rates than the neat PHBV.

The effect of quercetin on substance P-induced plasma extravasation in rat urinary bladder and its modulation by endogenous peptidases in conscious rats was studied. Plasma protein extravasation (PE) was assayed by measurement of extravasated Evans blue dye (μg/g dry tissue). Intravenous injection of substance P (SP, 10 nmol/kg) significantly increased PE in the urinary bladder. PE evoked by SP was increased significantly by quercetin (20 mg/kg, p.o.) pretreatment in the urinary bladder (73.5 ± 4.9 to 152.2 ± 9.9). Pretreatment with captopril, an angiotensin-converting enzyme (ACE) inhibitor (10 nmol/kg, i.v.), or with phosphoramidon, a neutral endopeptidase (NEP) inhibitor (2.5 μmol/kg, i.v.) also potentiated the SP-induced PE in urinary bladder, 286.2 ± 20.4 and 323.3 ± 34.0, respectively. Quercetin did not show any effect on neurokinin-A (NKA, 10 nmol/kg, i.v.) -induced plasma extravasation. The present study demonstrates that quercetin potentiates the PE induced by substance P in the urinary bladder. These effects suggest that this flavonoid might cause inhibition of NEP and/or ACE. Copyright © 2001 John Wiley & Sons, Ltd.

Objectives The aim of the present study was to evaluate the possible neurobehavioural effects in rats of the proanthocyanidin-rich fraction (PRF) isolated from the bark of Croton celtidifolius (Euphorbiaceae). Methods Adult Wistar rats were treated with the PRF (0.3–30 mg/kg) and evaluated in different behavioural paradigms classically used for the screening of drugs with psychoactive effects. Key findings Acute intraperitoneal (i.p.) administration of PRF decreased spontaneous locomotor activity (open field arena and activity cage), enhanced the duration of ethyl ether-induced hypnosis, increased the latency to the first convulsion induced by pentylenetetrazole (60 mg/kg, i.p.) and attenuated apomorphine-induced (0.5 mg/kg, i.p.) stereotyped behaviour. In lower doses, PRF (0.3 or 3 mg/kg, i.p.) increased the frequency of open arm entries in the elevated plus-maze test. Conclusions The present findings suggest that the systemic administration of PRF induces a wide spectrum of behavioural alterations in rats, consistent with the putative existence of hypnosedative, anticonvulsant and anxiolytic compounds.