991 resultados para cytokine


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After parturition, the somatotropic axis of the dairy cow is uncoupled, partly because of reduced concentration of liver-specific GH receptor (GHR) 1A. Estradiol-17 beta (E-2) concentrations increase at parturition and E-2 upregulates suppressors of cytokine signaling-2 (SOCS-2) mRNA expression, potentially inhibiting GH signaling. Therefore, we hypothesized that SOCS-2 mRNA is upregulated after parturition. Multiparous Holstein cows (n = 18) were dried off 45 d before expected parturition and fed diets to meet nutrient requirements at ad libitum or limited dry matter intake during the dry period. All cows were fed the same diet ad libitum from calving until 4 wk after parturition. Blood samples were collected weekly and more frequently near parturition. Liver biopsies obtained at -21, -7, 2, and 28 d relative to parturition were assessed for SOCS-2 and GHR 1A mRNA by quantitative real-time reverse-transcription PCR. The relative amount of SOCS-2 mRNA increased after parturition with both treatments and was greater on d 2 for cows limit-fed during the dry period compared with cows fed at ad libitum dry matter intake. Plasma E2 concentrations increased on d -13, -5 and 1 relative to parturition and the increases were greater in limit-fed cows. Plasma GH concentration was greater for limit-fed cows and increased after parturition in all cows. The amount of GHR 1A mRNA did not differ between diets but decreased on d 2. In addition to reduced GHR 1A, increased SOCS-2 mRNA after parturition, perhaps because of increased E-2, may further uncouple GH signaling in the liver of the transition dairy cow.

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Olive pomace oil, also known as "orujo" olive oil, is a blend of refined-pomace oil and virgin olive oil, fit for human consumption. Maslinic acid, oleanolic acid, erythrodiol, and uvaol are pentacyclic triterpenes, found in the non-glyceride fraction of orujo oil, which have previously been reported to have anti-inflammatory properties. In the present work, we investigated the effect of these minor components on pro-inflammatory cytokine production by human peripheral blood mononuclear cells in six different samples. Uvaol, erythrodiol, and oleanolic acid significantly decreased IL-1 beta and IL-6 production in a dose-dependent manner. All three compounds significantly reduced TNF-alpha production at 100 mu M; however, at 10 mu M, uvaol and oleanolic acid enhanced the generation of TNF-alpha. In contrast, maslinic acid did not significantly alter the concentration of those cytokines, with the exception of a slight inhibitory effect at 100 mu M. All four triterpenes inhibited production of I-309, at 50 mu M and 100 mu M. However, uvaol enhanced I-309 production at 10 mu M. The triterpenic dialcohols had a similar effect on MIG production. In conclusion, this study demonstrates that pentacyclic triterpenes in orujo oil exhibit pro- and anti-inflammatory properties depending on chemical structure and dose, and may be useful in modulating the immune response. (c) 2006 Elsevier Ltd. All rights reserved.

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Oxidized low-density lipoprotein (oxLDL) exhibits many atherogenic effects, including the promotion of monocyte recruitment to the arterial endothelium and the induction of scavenger receptor expression. However, while atherosclerosis involves chronic inflammation within the arterial intima, it is unclear whether oxLDL alone provides a direct inflammatory stimulus for monocyte-macrophages. Furthermore, oxLDL is not a single, well-defined entity, but has structural and physical properties which vary according to the degree of oxidation. We tested the hypothesis that the biological effects of oxLDL will vary according to its degree of oxidation and that some species of oxLDL will have atherogenic properties, while other species may be responsible for its inflammatory activity. The atherogenic and inflammatory properties of LDL oxidized to predetermined degrees (mild, moderate and extensive oxidation) were investigated in a single system using human monocyte-derived macrophages. Expression of CD36 mRNA was up-regulated by mildly- and moderately-oxLDL, but not highly-oxLDL. The expression of the transcription factor, proliferator-activated receptor-gamma (PPARgamma), which has been proposed to positively regulate the expression of CD36, was increased to the greatest degree by highly-oxLDL. However, the DNA binding activity of PPARgamma was increased only by mildly- and moderately-oxLDL. None of the oxLDL species appeared to be pro-inflammatory towards monocytes, either directly or indirectly through mediators derived from lymphocytes, regardless of the degree of oxidation. (C) 2003 Published by Elsevier Science Ireland Ltd.

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Parasitic infections cause a myriad of responses in their mammalian hosts, on immune as well as on metabolic level. A multiplex panel of cytokines and metabolites derived from four parasite-rodent models, namely, Plasmodium berghei-mouse, Trypanosoma brucei brucei-mouse, Schistosoma mansoni-mouse, and Fasciola hepatica-rat were statistically coanalyzed. 1H NMR spectroscopy and multivariate statistical analysis were used to characterize the urine and plasma metabolite profiles in infected and noninfected animals. Each parasite generated a unique metabolic signature in the host. Plasma cytokine concentrations were obtained using the ‘Meso Scale Discovery’ multi cytokine assay platform. Multivariate data integration methods were subsequently used to elucidate the component of the metabolic signature which is associated with inflammation and to determine specific metabolic correlates with parasite-induced changes in plasma cytokine levels. For example, the relative levels of acetyl glycoproteins extracted from the plasma metabolite profile in the P. berghei-infected mice were statistically correlated with IFN-γ, whereas the same cytokine was anticorrelated with glucose levels. Both the metabolic and the cytokine data showed a similar spatial distribution in principal component analysis scores plots constructed for the combined murine data, with samples from all infected animals clustering according to the parasite species and whereby the protozoan infections (P. berghei and T. b. brucei) grouped separately from the helminth infection (S. mansoni). For S. mansoni, the main infection-responsive cytokines were IL-4 and IL-5, which covaried with lactate, choline, and D-3-hydroxybutyrate. This study demonstrates that the inherently differential immune response to single and multicellular parasites not only manifests in the cytokine expression, but also consequently imprints on the metabolic signature, and calls for in-depth analysis to further explore direct links between immune features and biochemical pathways.

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Apolipoprotein E (APOE) genotype is believed to play an important role in cardiovascular risk. APOE4 carriers have been associated with higher blood lipid levels and a more pro-inflammatory state compared with APOE3/E3 individuals. Although dietary fat composition has been considered to modulate the inflammatory state in humans, very little is known about how APOE genotype can impact on this response. In a follow-up to the main SATgene study, we aimed to explore the effects of APOE genotype, as well as, dietary fat manipulation on ex vivo cytokine production. Blood samples were collected from a subset of SATgene participants (n = 52/88), prospectively recruited according to APOE genotype (n = 26 E3/E3 and n = 26 E3/E4) after low-fat (LF), high saturated fat (HSF) and HSF with 3.45 g docosahexaenoic acid (DHA) dietary periods (each diet eight weeks in duration assigned in the same order) for the measurement of ex vivo cytokine production using whole blood culture (WBC). Concentrations of IL-1beta, IL-6, IL-8, IL-10 and TNF-alpha were measured in WBC supernatant samples after stimulation for 24 h with either 0.05 or 1 lg/ml of bacterial lipopolysaccharide (LPS). Cytokine levels were not influenced by genotype, whereas, dietary fat manipulation had a significant impact on TNF-a and IL-10 production; TNF-a concentration was higher after consumption of the HSF diet compared with baseline and the LF diet (P < 0.05), whereas, IL-10 concentration was higher after the LF diet compared with baseline (P < 0.05). In conclusion, our study has revealed the amount and type of dietary fat can significantly modulate the production of TNF-a and IL-10 by ex vivo LPS-stimulated WBC samples obtained from normolipidaemic subjects.

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Dendritic cells (DC) can produce Th-polarizing cytokines and direct the class of the adaptive immune response. Microbial stimuli, cytokines, chemokines, and T cell-derived signals all have been shown to trigger cytokine synthesis by DC, but it remains unclear whether these signals are functionally equivalent and whether they determine the nature of the cytokine produced or simply initiate a preprogrammed pattern of cytokine production, which may be DC subtype specific. Here, we demonstrate that microbial and T cell-derived stimuli can synergize to induce production of high levels of IL-12 p70 or IL-10 by individual murine DC subsets but that the choice of cytokine is dictated by the microbial pattern recognition receptor engaged. We show that bacterial components such as CpG-containing DNA or extracts from Mycobacterium tuberculosis predispose CD8alpha(+) and CD8alpha(-)CD4(-) DC to make IL-12 p70. In contrast, exposure of CD8alpha(+), CD4(+) and CD8alpha(-)CD4(-) DC to heat-killed yeasts leads to production of IL-10. In both cases, secretion of high levels of cytokine requires a second signal from T cells, which can be replaced by CD40 ligand. Consistent with their differential effects on cytokine production, extracts from M. tuberculosis promote IL-12 production primarily via Toll-like receptor 2 and an MyD88-dependent pathway, whereas heat-killed yeasts activate DC via a Toll-like receptor 2-, MyD88-, and Toll/IL-1R domain containing protein-independent pathway. These results show that T cell feedback amplifies innate signals for cytokine production by DC and suggest that pattern recognition rather than ontogeny determines the production of cytokines by individual DC subsets.

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The leaves of the olive plant (Olea europaea) are rich in polyphenols, of which oleuropein and hydroxytyrosol (HT) are most characteristic. Such polyphenols have been demonstrated to favourably modify a variety of cardiovascular risk factors. The aim of the present intervention was to investigate the influence of olive leaf extract (OLE) on vascular function and inflammation in a postprandial setting and to link physiological outcomes with absorbed phenolics. A randomised, double-blind, placebo-controlled, cross-over, acute intervention trial was conducted with eighteen healthy volunteers (nine male, nine female), who consumed either OLE (51 mg oleuropein; 10mg HT), or a matched control (separated by a 4-week wash out) on a single occasion. Vascular function was measured by digital volume pulse (DVP), while blood collected at baseline, 1, 3 and 6 h was cultured for 24 h in the presence of lipopolysaccharide in order to investigate effects on cytokine production. Urine was analysed for phenolic metabolites by HPLC. DVP-stiffness index and ex vivo IL-8 production were significantly reduced (P < 0.05) after consumption of OLE compared to the control. These effects were accompanied by the excretion of several phenolic metabolites, namely HT and oleuropein derivatives, which peaked in urine after 8-24 h. The present study provides the first evidence that OLE positively modulates vascular function and IL-8 production in vivo, adding to growing evidence that olive phenolics could be beneficial for health.

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Background: Aggressive periodontitis is a specific form of periodontal disease that is characterized by rapid attachment loss and bone destruction. Cytokine profiles are of considerable value when studying disease course during treatment. The aim of this trial was to investigate cytokine levels in the gingival crevicular fluid (GCF) of patients with aggressive periodontitis, after treatment with photodynamic therapy (PDT) or scaling and root planing (SRP), in a split-mouth design on -7, 0, +1, +7, +30, and +90 days. Methods: Ten patients were randomly treated with PDT using a laser source associated with a photosensitizer or SRP with hand instruments. GCF samples were collected, and the concentrations of tumor necrosis factor-alpha (TNF-alpha) and receptor activator of nuclear factor-kappa B ligand (RANKL) were determined by enzyme-linked immunosorbent assays. The data were analyzed using generalized estimating equations to test the associations among treatments, evaluated parameters, and experimental times (alpha = 0.05). Results: Non-surgical periodontal treatment with PDT or SRP led to statistically significant reductions in TNF-alpha level 30 days following treatment. There were similar levels of TNF-alpha and RANKL at the different time points in both groups, with no statistically significant differences. Conclusion: SRP and PDT had similar effects on crevicular TNF-alpha and RANKL levels in patients with aggressive periodontitis. J Periodontol 2009;80:98-105.

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The purpose of this study was to evaluate the effect of a single application of antimicrobial photodynamic therapy (aPDT) on microbiological profile and cytokine pattern in dogs. Periodontal disease was induced by placing 3.0 silk ligatures around the mandibular pre-molars bilaterally during 8 weeks. The dogs were randomly treated with aPDT using a dye/laser system, scaling and root planning (SRP), or with the association of treatments (SRP + aPDT). Plaque samples were collected at baseline, 1, 3, and 4 weeks, and the mean counts of 40 species were determined using DNA-DNA hybridization. Gingival biopsies were removed and the expression of tumor necrosis factor alpha (TNF-alpha), receptor activator of NF-kB ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinase (MMP-1), interleukin (IL) 6, IL-10 and total bacterial load by analysis of 16 S rRNA gene were evaluated through real-time PCR. The results shows that the levels of the majority of the species were reduced 1 week post-therapy for all treatments, however, an increase in counts of Prevotella intermedia (p = 0.00), Prevotella. nigrescens (p = 0.00) and Tannerella forsythia (p = 0.00) was observed for aPDT and SRP + aPDT. After 4 weeks, a regrowth of Porphyromonas gingivalis (p = 0.00) and Treponema denticola (p = 0.00), was observed for all treatments. Also, a strikingly reduction of counts on counts of Aggregatibacter actinomycetemcomitans was observed for the aPDT (p = 0.00). For the cytokine pattern, the results were similar for all treatments, and a reduction in the expression of cytokines and bacterial load was observed throughout the study. Our results suggest that SRP, aPDT in a single application, and SRP + aPDT affects different bacterial species and have similar effects on the expression of cytokines evaluated during the treatment of ligature-induced periodontitis.

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This study reports the in vivo stimulatory effects of Cramoll 1,4 on rat spleen lymphocytes as evidenced by an increase in intracellular reactive oxygen species (ROS) production, Ca(2+) levels, and interleukin (IL)-1 beta expression. Cramoll 1,4 extracted from seeds of the Leguminosae Cratylia mollis Mart., is a lectin with antitumor and lymphocyte mitogenic activities. Animals (Nine-week-old male albino Wistar rats, Rattus norvegicus) were treated with intraperitoneal injection of Cramoll 1,4 (235 mu g ml(-1) single dose) and, 7 days later, spleen lymphocytes were isolated and analyzed for intracellular ROS, cytosolic Ca(2+), and IL-6, IL-10, and IL-1 mRNAs. Cell viability was investigated by annexin V-FITC and 7-amino-actinomycin D staining. The data showed that in lymphocytes activated by Cramoll 1,4 the increase in cytosolic and mitochondrial ROS was related to higher cytosolic Ca(2+) levels. Apoptosis and necrosis were not detected in statistically significant values and thus the lectin effector activities did not induce lymphocyte death. In vivo Cramoll 1,4 treatment led to a significant increase in IL-1 beta but IL-6 and -10 levels did not change. Cramoll 1,4 had modulator activities on spleen lymphocytes and stimulated the Th2 response.

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IL-1 beta, TNF-alpha, cytokine-induced neutrophil chemoattractant-2 alpha/beta, and IL-10 measurements were performed in elicited peritoneal cells from control, diabetic, and insulin-treated diabetic rats. Production/liberation of these cytokines was decreased in elicited peritoneal cells from diabetic rats. These changes were abolished by insulin treatment of diabetic rats. The alterations observed might be involved in the impaired inflammatory response and high occurrence of apoptosis observed in neutrophils under diabetic states.

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Skeletal muscle is the source of pro- and anti-inflammatory cytokines, and recently, it has been recognized as an important source of interleukin 6 (IL-6), a cytokine that exerts inhibitory effects on several pro-inflammatory cytokines. Although dynamic chronic resistance training has been shown to produce the known ""repeated bout effect"", which abolishes the acute muscle damage, performing of high-intensity resistance training has been regarded highly advisable, at least from the hypertrophy perspective. On the other hand, a more therapeutic, ""non-damaging"" resistance training program, mainly composed of concentric forces, low frequency/low volume of training, and the same exercise, could theoretically benefit the muscle when the main issue is to avoid muscle inflammation (as in the treatment of several ""low-grade"" inflammatory diseases) because the acute effect of each resistance exercise session could be diminished/avoided, at the same time that the muscle is still being overloaded in a concentric manner. However, the benefits of such ""less demanding"" resistance training schedule on the muscle inflammatory profile have never been investigated. Therefore, we assessed the protein expression of IL-6, TNF-alpha, IL-10, IL-10/TNF-alpha ratio, and HSP70 levels and mRNA expression of SCF(beta-TrCP), IL-15, and TLR-4 in the skeletal muscle of rats submitted to resistance training. Briefly, animals were randomly assigned to either a control group (S, n = 8) or a resistance-trained group (T, n = 7). Trained rats were exercised over a duration of 12 weeks (two times per day, two times per week). Detection of IL-6, TNF-alpha, IL-10, and HSP70 protein expression was carried out by western blotting and SCF(beta-TrCP) (SKP Cullin F-Box Protein Ligases), a class of enzymes involved in the ubiquitination of protein substrates to proteasomal degradation, IL-15, and TLR-4 by RT-PCR. Our results show a decreased expression of TNF-alpha and TLR4 mRNA (40 and 60%, respectively; p < 0.05) in the plantar muscle from trained, when compared with control rats. In conclusion, exercise training induced decreased TNF-alpha and TLR-4 expressions, resulting in a modified IL-10/TNF-alpha ratio in the skeletal muscle. These data show that, in healthy rats, 12-week resistance training, predominantly composed of concentric stimuli and low frequency/low volume schedule, down regulates skeletal muscle production of cytokines involved in the onset, maintenance, and regulation of inXammation.

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Doxorubicin (DOXO) is a potent chemotherapeutic used mainly against solid tumours; however, it has several side effects that can limit its clinical use. On the other hand, the effect of DOXO upon lymphocyte function is controversial. Some studies demonstrate that DOXO administration in vitro suppresses T-cell activation, while the cellular function has been shown to increase in vitro. The objective of this study was to investigate the effect of DOXO on lymphocyte cytokine production in rats. The animals were divided into: SAL (control, n = 10) and DOX (DOXO treated, n = 10). The DOX group received only one DOXO dose at 15 kg Kg(-1) by intraperitoneal injection. Forty-eight hours after DOXO administration, the animals were killed by decapitation. IL-2 production was significantly enhanced (p < 0.05) in lymphocytes from rats treated with DOXO (169.17 +/- 21.73 pg mL 10(5) cell) as compared to cells from SAL (45.92 +/- 10.53 pg mL 10(5) cell). The administration of DOXO decreased (<0.05) IL-4 production in the DOXO group (29.85 +/- 13.09 pg mL 10(5) cell) relative to the SAL group (75.08 +/- 15.31 pg mL 10(5) cell). The IL-2/IL-4 ratio was higher (<0.05) in the DOX group (5.99 +/- 0.44), as compared to SAL group (0.73 +/- 0.12). In conclusion, our results suggest that a dose of DOXO promotes an alteration in the Th1/Th2 balance, promoting a shift towards a Th1-dominant cytokine response. (C) 2010 Elsevier Masson SAS. All rights reserved.

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BACKGROUND AND PURPOSE The serine and cysteine peptidase inhibitor, BbCI, isolated from Bauhinia bauhinioides seeds, is similar to the classical plant Kunitz inhibitor, STI, but lacks disulphide bridges and methionine residues. BbCI blocks activity of the serine peptidases, elastase (K(iapp) 5.3 nM) and cathepsin G (K(iapp) 160.0 nM), and the cysteine peptidase cathepsin L (K(iapp) 0.2 nM). These three peptidases play important roles in the inflammatory process. EXPERIMENTAL APPROACH We measured the effects of BbCI on paw oedema and on leucocyte accumulation in pleurisy, both induced by carrageenan. Leucocyte-endothelial cell interactions in scrotal microvasculature in Wistar rats were investigated using intravital microscopy. Cytokine levels in pleural exudate and serum were measured by ELISA. KEY RESULTS Pretreatment of the animals with BbCI (2.5 mg.kg(-1)), 30 min before carrageenan-induced inflammation, effectively reduced paw oedema and bradykinin release, neutrophil migration into the pleural cavity. The number of rolling, adhered and migrated leucocytes at the spermatic fascia microcirculation following carrageenan injection into the scrotum were reduced by BbCI pretreatment. Furthermore, levels of the rat chemokine cytokine-induced neutrophil chemo-attractant-1 were significantly reduced in both pleural exudates and serum from animals pretreated with BbCI. Levels of interleukin-1 beta or tumour necrosis factor-alpha, however, did not change. CONCLUSIONS AND IMPLICATIONS Taken together, our data suggest that the anti-inflammatory properties of BbCI may be useful in investigations of other pathological processes in which human neutrophil elastase, cathepsin G and cathepsin L play important roles.

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Apocynin has been extensively used as an inhibitor of NADPH oxidase (NOX) in many experimental models using phagocytic and non-phagocytic cells. Currently, there is some controversy about the efficacy of apocynin in non-phagocytic cells, but in phagocytes the reported results are consistent, which could be due to the presence of myeloperoxidase in these cells. This enzyme has been proposed as responsible for activating apocynin by generating its dimer, diapocynin, which is supposed to be the active compound that prevents NADPH oxidase complex assembly and activation. Here, we synthesized diapocynin and studied its effect on inhibition of gp91(phox) RNA expression. We found that diapocynin strongly inhibited the expression of gp91(phox)mRNA in peripheral blood mononuclear cells (PBMC). Only at a higher concentration, apocynin was able to exert the same effect. We also compared the apocynin and diapocynin efficacy as inhibitors of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) production in response to lipopolysaccharide (LPS)-activated PBMC. Although apocynin did inhibit TNF-alpha production, diapocynin had a much more pronounced effect, on both TNF-alpha and IL-10 production. In conclusion, these findings suggest that the bioconversion of apocynin to diapocynin is an important issue not limited to enzymatic activity inhibition, but also for other biological effects as gp91(phox) mRNA expression and cytokine production. Hence, as diapocynin can be easily prepared from apocynin, a one-step synthesis, we recommend its use in studies where the biological effects of apocynin are searched. (C) 2010 Elsevier Inc. All rights reserved.