931 resultados para bioactive molecules


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Immunomodulation is a common feature of chronic helminth infections and mainly attributed to the secretion of bioactive molecules, which target and modify host immune cells. In this study, we show that the helminth immunomodulator AvCystatin, a cysteine protease inhibitor, induces a novel regulatory macrophage (Mreg; AvCystatin-Mreg), which is sufficient to mitigate major parameters of allergic airway inflammation and colitis in mice. A single adoptive transfer of AvCystatin-Mreg before allergen challenge suppressed allergen-specific IgE levels, the influx of eosinophils into the airways, local and systemic Th2 cytokine levels, and mucus production in lung bronchioles of mice, whereas increasing local and systemic IL-10 production by CD4(+) T cells. Moreover, a single administration of AvCystatin-Mreg during experimentally induced colitis strikingly reduced intestinal pathology. Phenotyping of AvCystatin-Mreg revealed increased expression of a distinct group of genes including LIGHT, sphingosine kinase 1, CCL1, arginase-1, and costimulatory molecules, CD16/32, ICAM-1, as well as PD-L1 and PD-L2. In cocultures with dendritic cells and CD4(+) T cells, AvCystatin-Mreg strongly induced the production of IL-10 in a cell-contact-independent manner. Collectively, our data identify a specific suppressive macrophage population induced by a single parasite immunomodulator, which protects against mucosal inflammation.

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A bioengenharia de tecidos baseia-se no uso de moléculas bioativas, células-tronco e biomateriais para reparação de tecidos e/ou órgãos. Biomateriais podem ser classificados de acordo com sua origem em sintéticos ou biológicos. Biomateriais biológicos podem ser produzidos por decelularização, que visa a remoção de células da matriz extracelular (MEC), a qual deve manter sua integridade química e física. Placentas são órgãos de grande interesse na bioengenharia de tecidos visto que são descartadas após o parto e possuem grande volume de matriz extracelular. Métodos de decelularização podem ser classificados em químicos, físicos e enzimáticos. Todos conhecidamente causam alterações na MEC, sendo que a associação deles é comumente utilizada. Este trabalho comparou diferentes protocolos e estabeleceu um método mais favorável para a decelularização de placentas caninas, visando a produção de um biomaterial para futuras aplicações clínicas. Inicialmente ambas as porções - materna e fetal - das placentas foram submetidas à 10 protocolos, que avaliaram variáveis como concentração e tempo de incubação em detergentes, diferentes gradientes de temperatura e a influência da perfusão versus imersão das soluções, na MEC remanescente. Com base na transparência do tecido e na ausência de núcleo celular em cortes histológicos, dois protocolos foram selecionados (I e II). Além dos critérios já mencionados, ambos os protocolos foram comparados quanto à quantidade de DNA remanescente na MEC decelularizada e à permanência e distribuição de algumas das proteínas da matriz. O detergente SDS foi o mais eficaz na remoção de células, embora não tenha sido suficiente para promover uma decelularização tecidual completa. O congelamento prévio das placentas requereu um maior tempo de incubação posterior das amostras nos distintos detergentes. Ambos métodos de perfusão e imersão foram eficazes na remoção das células, embora grande concentração de proteínas do citoesqueleto tenham permanecido retidas na matriz. As amostras processadas pelo protocolo I (SDS 1%, 5mM EDTA + 50mM TRIS + 0,5% antibiótico, e Triton X-100 1%) apresentaram maior preservação da organização estrutural da MEC quando comparadas àquelas processadas de acordo com o protocolo II (que diferiu do anterior pela utilização de solução contendo 0,05% tripsina ao invés de 50mM TRIS), esse último método entretanto foi o que melhor removeu as células das placentas, conforme observado em lâminas histológicas e demonstrado pela menor concentração de DNA. Tanto as porções materna quanto fetal submetidas à ambos protocolos, mantiveram as proteínas laminina, fibronectina e colágeno tipo I. O colágeno tipo III foi observado somente na porção fetal. Conclui-se que o protocolo II foi o mais eficaz no processo de decelularização de placentas caninas tendo promovido a remoção do conteúdo celular e diminuição da concentração de DNA na MEC remanescente. No entanto é necessário otimizar o tempo de incubação das placentas em soluções enzimáticas visando maior conservação do arranjo da matriz decelularizada. A análise da capacidade da MEC decelularizada por tal método para ser utilizada em bioengenharia de tecidos ainda deve ser avaliada in vitro e in vivo

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Microporous, poly(ε-caprolactone) (PCL) matrices were loaded with progesterone by precipitation casting using co-solutions of PCL and progesterone in acetone. Progesterone loadings up to 32% w/w were readily achieved by increasing the drug content of the starting PCL solution. The kinetics of steroid release in PBS at 37°C over 10 days could be described effectively by a diffusional release model although the Korsmeyer-Peppas model indicated the involvement of multiple release phenomena. The diffusion rate constant (D) increased from 8 to 24 μg/mg matrix/day0.5 as the drug loading increased from 3.6 to 12.4% w/w. A total cumulative release of 75%-95% indicates the high efficiency of steroid delivery. Increasing the matrix density from 0.22 to 0.39 g/cm3, by increasing the starting PCL solution concentration, was less effective in changing drug release kinetics. Retention of anti-proliferative activity of released steroid was confirmed using cultures of breast cancer epithelial (MCF-7) cells. Progesterone released from PCL matrices into PBS at 37°C over 14 days retarded the growth of MCF-7 cells by a factor of at least 3.5 compared with progesterone-free controls. These findings recommend further investigation of precipitation-cast PCL matrices for delivery of bioactive molecules such as anti-proliferative agents from implanted, inserted or topical devices.

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Significance: Oxidized phospholipids are now well-recognized as markers of biological oxidative stress and bioactive molecules with both pro-inflammatory and anti-inflammatory effects. While analytical methods continue to be developed for studies of generic lipid oxidation, mass spectrometry (MS) has underpinned the advances in knowledge of specific oxidized phospholipids by allowing their identification and characterization, and is responsible for the expansion of oxidative lipidomics. Recent Advances: Studies of oxidized phospholipids in biological samples, both from animal models and clinical samples, have been facilitated by the recent improvements in MS, especially targeted routines that depend on the fragmentation pattern of the parent molecular ion and improved resolution and mass accuracy. MS can be used to identify selectively individual compounds or groups of compounds with common features, which greatly improves the sensitivity and specificity of detection. Application of these methods have enabled important advances in understanding the mechanisms of inflammatory diseases such as atherosclerosis, steatohepatitis, leprosy and cystic fibrosis, and offer potential for developing biomarkers of molecular aspects of the diseases. Critical Issues and Future Directions: The future in this field will depend on development of improved MS technologies, such as ion mobility, novel enrichment methods and databases and software for data analysis, owing to the very large amount of data generated in these experiments. Imaging of oxidized phospholipids in tissue MS is an additional exciting direction emerging that can be expected to advance understanding of physiology and disease.

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Bioactive molecules in berries may be helpful in reducing the risk of oral diseases. The aim of this study was to determine the effect of bilberry consumption on the outcome of a routine dental clinical parameter of inflammation, bleeding on probing (BOP), as well as the impact on selected biomarkers of inflammation, such as cytokines, in gingival crevicular fluid (GCF) in individuals with gingivitis. Study individuals who did not receive standard of care treatment were allocated to either a placebo group or to groups that consumed either 250 or 500 g bilberries daily over seven days. The placebo group consumed an inactive product (starch). A study group, receiving standard of care (debridement only) was also included to provide a reference to standard of care treatment outcome. Cytokine levels were assayed using the Luminex MagPix system. The mean reduction in BOP before and after consumption of test product over 1 week was 41% and 59% in the groups that consumed either 250 or 500 g of bilberries/day respectively, and was 31% in the placebo group, and 58% in the standard of care reference group. The analysis only showed a significantreduction in cytokine levels in the group that consumed 500 g of bilberries/day. A statistically significant reduction was observed for IL-1β (p = 0.025), IL-6 (p = 0.012) and VEGF (p = 0.017) in GCF samples in the group that consumed 500 g of bilberries daily. It appears that berry intake has an ameliorating effect on some markers of gingival inflammation reducing gingivitis to a similar extent compared to standard of care.

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Microporous polycaprolactone (PCL) matrices loaded with hydrophobic steroidal drugs or a hydrophilic drug - pilocarpine hydrochloride - were produced by precipitation casting using solutions of PCL in acetone. The efficiency of steroid incorporation in the final matrix (progesterone (56 %) testosterone (46 %) dexamethasone (80 %)) depended on the nature of the drug initially co-dissolved in the PCL solution. Approximately 90 % w/w of the initial load of progesterone, 85 % testosterone and 50 % dexamethasone was released from the matrices in PBS at 37°C over 8 days. Pilocarpine hydrochloride (PH)-loaded PCL matrices, prepared by dispersion of powder in PCL solution, released 70-90 % of the PH content over 12 days in PBS. Application of the Higuchi model revealed that the kinetics of steroid and PH release were consistent with a Fickian diffusion mechanism with corresponding diffusion coefficients of 5.8 × 10-9 (progesterone), 3.9 × 10 -9 (testosterone), 7.1 × 10-10 (dexamethasone) and 22 × 10-8 cm2/s (pilocarpine hydrochloride). The formulation techniques described are expected to be useful for production of implantable, insertable and topical devices for sustained delivery of a range of bioactive molecules of interest in drug delivery and tissue engineering.

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Antiophidic activity from decoct of Jatropha gossypiifolia L. leaves against Bothrops jararaca venom. Snakebites are a serious worldwide public health problem. In Latin America, about 90 % of accidents are attributed to snakes from Bothrops genus. Currently, the main available treatment is the antivenom serum therapy, which has some disadvantages such as inability to neutralize local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies to treat snakebites is relevant. Jatropha gossypiifolia L., a medicinal plant popularly known in Brazil as “pinhão-roxo”, is very used in folk medicine as antiophidic. So, the aim of this study is to evaluate the antiophidic properties of this species against enzymatic and biological activities from Bothrops jararaca snake venom. The aqueous leaf extract of J. gossypiifolia was prepared by decoction. The inhibition studies were performed in vitro, by pre-incubation of a fixed amount of venom with different amounts of extract from J. gossypiifolia for 60 min at 37 °C, and in vivo, through oral or intraperitoneal treatment of animals, in different doses, 60 min before venom injection. The proteolytic activity upon azocasein was efficiently inhibited, indicating inhibitory action upon metalloproteinases (SVMPs) and/or serine proteases (SVSPs). The extract inhibited the fibrinogenolytic activity, which was also confirmed by zymography, where it was possible to observe that the extract preferentially inhibits fibrinogenolytic enzymes of 26 and 28 kDa. The coagulant activity upon fibrinogen and plasma were significantly inhibited, suggesting an inhibitory action upon thrombin-like enzymes (SVTLEs), as well as upon clotting factor activators toxins. The extract prolonged the activated partial thromboplastin time (aPTT), suggesting an inhibitory action toward not only to SVTLEs, but also against endogenous thrombin. The defibrinogenating activity in vivo was efficiently inhibited by the extract on oral route, confirming the previous results. The local hemorrhagic activity was also significantly inhibited by oral route, indicating an inhibitory action upon SVMPs. The phospholipase activity in vitro was not inhibited. Nevertheless, the edematogenic and myotoxic activities were efficiently inhibited, by oral and intraperitoneal route, which may indicate an inhibitory effect of the extract upon Lys49 phospholipase (PLA2) and/ or SVMPs, or also an anti-inflammatory action against endogenous chemical mediators. Regarding the possible action mechanism, was observed that the extract did not presented proteolytic activity, however, presented protein precipitating action. In addition, the extract showed significant antioxidant activity in different models, which could justify, at least partially, the antiophidic activity presented. The metal chelating action presented by extract could be correlated with SVMPs inhibition, once these enzymes are metal-dependent. The phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins, from which the flavonoids could be pointed as major compounds, based on chromatographic profile obtained by thin layer chromatography (TLC). In conclusion, the results demonstrate that the J. gossypiifolia leaves decoct present potential antiophidic activity, including action upon snakebite local effects, suggesting that this species may be used as a new source of bioactive molecules against bothropic venom.

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Hancornia speciosa Gomes (Apocynaceae), popularly known as ‘mangabeira’, has been used in folk medicine to treat inflammatory disorders, hypertension, dermatitis, diabetes, liver diseases and stomach disorders. Regarding the Hancornia speciosa fruits, the ethnobotany indicates its use especially for treating inflammation and tuberculosis. However, no study has been done so far to prove such biological activities. The objective was evaluation anti-inflammatory activity from the fruits of Hancornia speciosa Gomes (mangabeira). Aqueous extract was prepared by decoction, subsequently submitted the liquid-liquid fractionation. The secondary metabolites were identified by high performance liquid chromatography coupled with detector diode array (HPLC-DAD) and liquid chromatography diode array detector coupled with mass spectrometry (LC-DAD-MS). The anti-inflammatory properties of the aqueous extract, dichloromethane (CH2Cl2), ethyl acetate (EtOAc) and n-butanol (n-BuOH) fractions of the fruits from H. speciosa, as well as rutin and chlorogenic acid were investigated using in vitro and in vivo models. In vivo tests comprised the xylene-induced ear edema that was measured the formation of edema, carrageenan-induced peritonitis was evaluated the total leukocytes at 4h and zymosan-induced air pouch was measured the total leukocytes and differential cell count at 6, 24 and 48 hours, whereas in vitro tests were evaluated levels of cytokines IL-1β, IL-6, IL-12 and TNF-α using ELISA obtained of carrageenan-induced peritonitis model. The results showed the presence of rutin and chlorogenic acid were detected in the aqueous extract from H. speciosa fruits by HPLC-DAD and LC-DAD-ME. Furthermore, the aqueous extracts and fractions, as well as rutin and chlorogenic acid significantly inhibited the xilol-induced ear edema and reduced cell migration in the animal models such as carrageenan-induced peritonitis and zymosan-induced air pouch. In addition, reduced levels of cytokines IL-1β, IL-6, IL-12 and TNF-α were observed. This is the first study that demonstrated the anti-inflammatory effect of aqueous extract from Hancornia speciosa fruits against different inflammatory agents in animal models, suggesting that their bioactive molecules, especially rutin and chlorogenic acid contributing, at least in part, to the anti-inflammatory effect of aqueous extract. These findings support the widespread use of Hancornia speciosa in popular medicine and demonstrate that this aqueous extract has therapeutic potential for the development of a herbal drugs with anti-inflammatory properties.

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Fucans, sulphated polysaccharides that contain L-fucose in its constitution, obtained from species of Phaeophyceae of the Sargassum kind, display several biological activities. Heterofucans from Sargassum filipendula are bioactive molecules that contain strong antiproliferative and antioxidant activity. However, their immunomodulatory and antimicrobial activities have not yet been examined. In this context, the aim of this research was to evaluate the heterofucans as for their immunomodulatory capacity and antimicrobial action against Leishmania infantum, Trichomonas vaginalis, Staphylococcus epidermidis and Klebsiella pneumonia (KPC). The five heterofucans obtained from S. filipendula show activities that are distant as stimulants of the immune system and microbial agent. The SF0.5V, SF0.7V amd SF1.0V heterofucans were capable of acting in the activation of murine and human macrophages. In addition to that, SF0.5V has shown antibiofilm activity of S. epidermides and SF0.7V and 1.0V almost completely inhibited the survival of the protozoan T. vaginalis. Results such as this one, reflect the broad range of action of the sulphated polysaccharides obtained from seaweeds, especially from the species S.filipendula

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Amphibian skin secretions are unique sources of bioactive molecules, particularly bioactive peptides. In this study, the skin secretion of the white-lipped tree frog (Litoria infrafrenata) was obtained to identify peptides with putative therapeutic potential. By utilizing skin secretion-derived mRNA, a cDNA library was constructed, a frenatin gene was cloned and its encoded peptides were deduced and confirmed using RP-HPLC, MALDI-TOF and MS/MS. The deduced peptides were identified as frenatin 4.1 (GFLEKLKTGAKDFASAFVNSIKGT) and a post-translationally modified peptide, frenatin 4.2 (GFLEKLKTGAKDFASAFVNSIK.NH2). Antimicrobial activity of the peptides was assessed by determining their minimal inhibitory concentrations (MICs) using standard model microorganisms. Through studying structure–activity relationships, analogues of the two peptides were designed, resulting in synthesis of frenatin 4.1a (GFLEKLKKGAKDFASALVNSIKGT) and frenatin 4.2a (GFLLKLKLGAKLFASAFVNSIK.NH2). Both analogues exhibited improved antimicrobial activities, especially frenatin 4.2a, which displayed significant enhancement of broad spectrum antimicrobial efficiency. The peptide modifications applied in this study, may provide new ideas for the generation of leads for the design of antimicrobial peptides with therapeutic applications.

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Background. Tremendous advances in biomaterials science and nanotechnologies, together with thorough research on stem cells, have recently promoted an intriguing development of regenerative medicine/tissue engineering. The nanotechnology represents a wide interdisciplinary field that implies the manipulation of different materials at nanometer level to achieve the creation of constructs that mimic the nanoscale-based architecture of native tissues. Aim. The purpose of this article is to highlight the significant new knowledges regarding this matter. Emerging acquisitions. To widen the range of scaffold materials resort has been carried out to either recombinant DNA technology-generated materials, such as a collagen-like protein, or the incorporation of bioactive molecules, such as RDG (arginine-glycine-aspartic acid), into synthetic products. Both the bottom-up and the top-down fabrication approaches may be properly used to respectively obtain sopramolecular architectures or, instead, micro-/nanostructures to incorporate them within a preexisting complex scaffold construct. Computer-aided design/manufacturing (CAD/CAM) scaffold technique allows to achieve patient-tailored organs. Stem cells, because of their peculiar properties - ability to proliferate, self-renew and specific cell-lineage differentiate under appropriate conditions - represent an attractive source for intriguing tissue engineering/regenerative medicine applications. Future research activities. New developments in the realization of different organs tissue engineering will depend on further progress of both the science of nanoscale-based materials and the knowledge of stem cell biology. Moreover the in vivo tissue engineering appears to be the logical step of the current research.

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Currently, carotenoids are valuable bioactive molecules for several industries, such as chemical, pharmaceutical, food and cosmetics, due to their multiple benefits as natural colorants, antioxidants and vitamin precursors. Hence, the increasing interest on these high added-value products has led to the search of alternatives, more cost-effective and with better yields, towards their industrial production. Indeed, microbial metabolism offers a promising option for carotenoids production. Herein it is shown the potential of the dibenzothiophene desulfurizing bacterium Gordonia alkanivorans strain 1B as a high carotenoid-producer microorganism. The novel carotenoids, produced under different culture conditions, were extracted with DMSO and then further analyzed both through spectrophotometry and HPLC. When grown in glucose-sulfate-light, strain 1B was able of achieving 2015 g carotenoids per g DCW in shake-flask assays, with about 60% corresponding to lutein, canthaxanthin and astaxanthin. Further optimization studies open a new focus of research aiming to get a hyper pigment-producer strain that may be applied towards different industrial sectors.

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The exopolysaccharides are extracellular compounds produced by some species of fungi and bacteria. It is suggested that these molecules, even when in the form of complex polysaccharide-peptide, are the main bioactive molecules of many fungus. Some of the biological activities displayed by these compounds can be accentuated and others may arise when you add chemically polar or nonpolar groups to polysaccharides. The fruiting body of Pleurotus sajor-caju produces a heteropolysaccharide with antineoplastic and antimicrobial activity, but other biological activities of this polymer have not been evaluated. In this work the exopolysaccharide of Pleurotus sajor-caju was sulfated chemically and structurally characterized. We also evaluated the antiproliferative, antioxidant and anticoagulant activities from native exopolysaccharide (PN) and its sulfated derivated (PS). Polyacrylamide gel electrophoresis, infrared spectroscopy and nuclear magnetic resonance (¹³C) proved successful in sulfation of PN to obtain PS. Analysis by gas chromatography-mass spectroscopy showed that PN and PS are composed of mannose, galactose, 3-O-methyl-galactose and glucose in proportion percentage of 44,9:16,3:19,8:19 and 49, 7:14,4:17,7:18,2, respectively. The percentage of sulfate found in PS was 22.5%. Antioxidants assays revealed that the sulfation procedure affects differently the activities of exopolysaccharides, while the total antioxidant capacity, the scavenging activity of superoxide radical and ferric chelating were not affected by sulfation, on the other hand the chemical modification of PN enhanced the scavenging activity of hydroxyl radical and reducing power. PS also showed anticoagulant activity in a dose-dependent manner and clotting time was 3.0 times higher than the baseline value in APTT at 2 mg/mL. The exopolysaccharide not presented antiproliferative activity against HeLa tumor cells, but PS affects the cellular proliferation in a time-dependent manner. After 72 h, the inhibition rate of PS (2.0 mg/mL) on HeLa cells was about 60%. The results showed that PN sulfation increase some of their activities.

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In recent years the interest in naturally occurring compounds has been increasing worldwide. Indeed, many of the bioactive compounds currently used as medicines have been synthesized based on the structure of natural compounds [1]. In order to obtain bioactive fractions and subsequently isolated compounds derived from natural matrices, several procedures have been carried out. One of these is to separate and assess the concentration of the active compound(s) present in the samples, a step in which the chromatographic techniques stand out [2]. In the present work the mushroom Sui/Ius granulatus (L.) Roussel was chemically characterized by chromatographic techniques coupled to different detectors, in order to evaluate the presence of nutritional and/or bioactive molecules. Some hydrophilic compounds, namely free sugars, were identified by high performance liquid chromatography coupled to a refraction index detector (HPLC-RI), and organic and phenolic acids were assessed by HPLC coupled to a photodiode array detector (HPLC-PDA). Regarding lipophilic compounds, fatty acids weredetermined by gas chromatography with a flame ionization detector (GC-FID) and tocopherols by HPLC-fluorescence detection. Mannitol and trehalose were the main free sugars detected. Different organic acids were also identified (i.e. oxalic, quinic and fumaric acids), as well as phenolic acids (i.e. gallic and p-hydroxybenzoic acids) and the related compound cinnamic acid. Mono- and polyunsaturated fatty acids were the prevailing fatty acids and a-, ~- and ~-tocopherol were the isoforms of vitamin E detected in the samples. Since this species proved to be a source of biologically active compounds, the antioxidant and antimicrobial properties were evaluated. The antioxidant activity was measured through the reducing power, free radical's scavenging activity and lipid peroxidation inhibition of its methanolic extract, and the antimicrobial activity was also tested in Gram positive and Gram negative bacteria and iri different fungi. S. granulatus presented antioxidant properties in all the performed assays, and proved to inhibit the growth of different bacterial and fungal strains. This study is a first step for classifying S. granulatus as a functional food, highlighting the potential of mushrooms as a source of nutraceutical and biologically active compounds.