Diapocynin versus apocynin as pretranscriptional inhibitors of NADPH oxidase and cytokine production by peripheral blood mononuclear cells

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.

Chronic exercise decreases cytokine production in healthy rat skeletal muscle

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). Acute physical exercise is known to induce a pro-inflammatory cytokine profile in the plasma. However, the effect of chronic physical exercise in the production of pro- and anti-inflammatory cytokines by the skeletal muscle has never been examined. We assessed IL-6, TNF-alpha, IL-1 beta and IL-10 levels in the skeletal muscle of rats submitted to endurance training. Animals were randomly assigned to either a Sedentary group (S, n = 7) or an endurance exercise trained group (T, n = 8). Trained rats ran on a treadmill for 5 days week(-1) for 8 weeks (60% VO(2max)). Detection of IL-6, TNF-alpha, IL-1 beta and IL-10 protein expression was carried out by ELISA. We found decreased expression of IL-1 beta, IL-6, TNF-alpha and IL-10 (28%, 27%. 32% and 37%, respectively, p < 0.05) in the extensor digital longus (EDL) from T, when compared with S. In the soleus, IL-1 beta, TNF-alpha and IL-10 protein levels were similarly decreased (34%, 42% and 50%, respectively, p < 0.05) in T in relation to S, while IL-6 expression was not affected by the training protocol. In conclusion, exercise training induced decreased cytokine protein expression in the skeletal muscle. These data show that in healthy rats, 8-week moderate-intensity aerobic training down regulates skeletal muscle production of cytokines involved in the onset, maintenance and regulation of inflammation, and that the response is heterogeneous according to fibre composition. Copyright (C) 2009 John Wiley & Sons, Ltd.

Stimulation of cytokine production in human peripheral blood mononuclear cells by an aqueous Chlorella extract

CPE is an aqueous extract of the edible micro alga Chlorella pyrenoidosa, which has been shown to have immunostimulatory effects in vivo. In the present study, CPE was evaluated for an ability to stimulate cytokine production by human peripheral blood mononuclear cells (PBMC). PBMC from healthy individuals were treated ex vivo for 24 hours with 1, 10 and 100 μg/mL CPE. This resulted in a marked increase in the level of IL-10, a regulatory cytokine, and strong stimulation of the T-helper-1 (Th1) cell cytokines, IFN-γ and TNF-α. In contrast, stimulation of representative T-helper-2 (Th2) cell cytokines, IL-4 and IL-13, was minor. CPE (1, 10 or 100 μg/mL) did not cause a proliferation of human PBMC suggesting that enhanced secretion of cytokines was not secondary to an increase in cell number. We conclude that CPE stimulation of human PBMC induces a Th1-patterned cytokine response and a strong anti-inflammatory regulatory cytokine response, observations that await confirmation in vivo.

Whole blood analysis of phagocytosis, apoptosis, cytokine production, and leukocyte subsets in healthy older men and women: the ZENITH study

Few studies to date have examined age-related changes in markers of immune status in healthy older individuals. The immune status of 93 healthy individuals aged 55–70 years was assessed by two- and three-color flow cytometry and biochemical analysis. There were significant age effects (p ≤.05) on monocyte phagocytic activity and cluster of differentiation (CD) 3/human leukocyte antigen-D-related (HLA-DR) late-activated T lymphocytes (% expression). There was a significant (p ≤ 0.1) Age x Sex interaction in absolute counts (x 10⁹/L) of CD3/CD8 total cytotoxic T lymphocytes (CTL), the CD4 T- helper to CD8 CTL ratio, the CD3/CD4/CD45RA naïve T helper to CD3/CD4/CD45RO memory T helper lymphocyte ratio, and interleukin (IL)-1ß (% expression) by activated monocytes. The study shows that alterations in markers of immune status occur between 55 and 70 years, and provides reference values for the lymphocyte measures in healthy men and postmenopausal women in this age group. The study further highlights the need for sex-specific reference ranges for such markers.

Impact of training on changes in perceived stress and cytokine production

Data on training of competitive athletes and the inflammatory response, and, more specifically, the utility of psychological inventories to monitor this response in regards to overreaching is limited. The aim of the present study was to investigate the association of the Perceived Stress Scale (PSS) and inflammatory markers in elite rowers. Eight rowers (males n = 4; females n = 4) were monitored over an 8-week training period, comprising 12 sessions each week and training an average 3.11 h·d-1. Training volume was periodized weekly while intensity was maintained throughout the study. Perceived stress was measured weekly pretraining, and capillary blood samples (500 μL) were taken post-training. Significant associations between perceived stress and cytokines interleukin-6 (p < .05) and tumor necrosis factor alpha (p < .05) were observed. While further investigation of the role of cytokines in the overtraining process is required, these data provide preliminary support for an association between perceived stress and the inflammatory responses to training.

Effect of cell-surface components and metabolites of lactic acid bacteria and probiotic organisms on cytokine production and induction of CD25 expression in human peripheral mononuclear cells

In the current study, the relative contribution of cell-surface components (CSC) and cell-free supernatants (CFS) in the immuno-modulatory properties of 17 strains of probiotic and lactic acid bacteria (LAB) was assessed. The production of pro- and antiinflammatory cytokines including IL-2, IL-4, IL-10, IL-12 p70, IFN-γ, tumor necrosis factor-α (TNF-α), and transforming growth factor-β was measured at different time points after stimulation of buffy coat derived-peripheral blood mononuclear cells (PBMC) from healthy donors with CSC and CFS of probiotic and LAB. Results showed that CSC of probiotic and LAB strains induced production of T helper 1 and 2 type cytokines. Transforming growth factor-β was stimulated at highest concentrations, followed by IL-10 and TNF-α. The CFS of all tested bacterial strains induced PBMC for significantly high levels of IL-10 secretion compared with unstimulated cells, but the values were less than lipopolysaccharide-stimulated cells. Cytokines due to CFS stimulation showed declined concentration for IL-2, TNF-α, and IL-4, and complete disappearance of IL-12, IFN-γ, and transforming growth factor-β in the cultured medium at 96 h of incubation. Results of cytokine data demonstrate proinflammatory TNF-α immune responses are mainly directed through cell-surface structures of probiotic and LAB, but antiinflammatory immune responses are mediated both by metabolites and cell-surfaces of these bacteria. The induction of CD4(+)CD25(+) regulatory T cells after stimulation of PBMC with CSC and CFS of probiotic and LAB showed regulatory T cell activity appeared to be influenced both by the CSC and metabolites, but was principally triggered by cell surfaces of probiotic and LAB strains.

Diapocynin versus apocynin as pretranscriptional inhibitors of NADPH oxidase and cytokine production by peripheral blood mononuclear cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Interleukin-6 treatment enhances human monocyte permissiveness for Paracoccidioides brasiliensis growth by modulating cytokine production

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Silibinin modulates the NF-kappa b pathway and pro-inflammatory cytokine production by mononuclear cells from preeclamptic women

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Analysis of the expression of toll-like receptors 2 and 4 and cytokine production during experimental Leishmania chagasi infection

Toll-like receptors (TLRs) recognise pathogen-derived molecules and influence immunity to control parasite infections. This study aimed to evaluate the mRNA expression of TLRs 2 and 4, the expression and production of the cytokines interleukin (IL)-12, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-17, IL-10 and transforming growth factor (TGF)-β and the production of nitric oxide (NO) in the spleen of mice infected with Leishmania chagasi. It also aimed to evaluate any correlations between mRNA expression TLR2 and 4 and cytokines and NO production. Infection resulted in increased TLR2-4, IL-17, TNF-α and TGF-β mRNA expression during early infection, with decreased expression during late infection correlating with parasite load. IFN-γ and IL-12 mRNA expression decreased at the peak of parasitism. IL-10 mRNA expression increased throughout the entire time period analysed. Although TGF-β, TNF-α and IL-17 were highly produced during the initial phase of infection, IFN-γ and IL-12 exhibited high production during the final phase of infection. IL-10 and NO showed increased production throughout the evaluated time period. In the acute phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17, NO, IL-10 and TGF-β expression and parasite load. During the chronic phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17 and TGF-β expression and parasite load. Our data suggest that infection by L. chagasi resulted in modulation of TLRs 2 and 4 and cytokines.

Titanium surfaces with nanotopography modulate cytokine production in cultured human gingival fibroblasts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytokine production in lungs and adrenal glands of high and low antibody producing mice infected with Paracoccidioides brasiliensis

Mice genetically selected for high (H) and low (L) antibody production (HIV-A and L-IV-A) were used in an experimental model of paracoccidioidomycosis. In a previous work, it was observed that male HIV-A animals were more susceptible to the infection due to adrenal gland damage. Male HIV-A and LIV-A animals were intravenously inoculated with Paracoccidioides brasiliensis (strain 18) and sacrificed 2, 4, 6, 8 and 10 weeks after inoculation. At each time interval, lungs and adrenals were removed to estimate recoverability of the fungus, as well as to determine Th1 (IFN-gamma, TNF-alpha) and Th2 (IL-4 and IL-10) cytokine profiles. While viable fungi recoverability from the lungs of HIV-A mice was higher after 4 and 8 weeks, there was less fungal recovery from the adrenals of LIV-A animals after the 2nd week, with total fungal elimination after the 8th week. With regard to Th2 cytokines, there was an inhibition in IL-4 production in the organs from infected animals, the extent of which varied according to the organ and the time period after initiation of infection. IL-10 production was found to be lower in both organs. Determination of Th1 cytokines revealed that IFN-gamma production increased in both organs, mainly in the adrenal of LIV-A after 8 and 10 weeks, when these animals showed a total fungal elimination. A significant difference was observed between HIV-A and LIV-A concerning TNF-alpha production in both organs and at all recovery times, in that LIV-A produced a higher level of this cytokine, mainly in the adrenal. These results may explain the high susceptibility of HIV-A to P. brasiliensis infection, is due, at least in part, to adrenal involvement. The higher production of Th1 cytokines by LIV-A in comparison to HIV-A mice may account for LIV-A resistance to P. brasiliensis infection. Our data reveal the importance of this experimental model in the study of the adrenal involvement in paracoccidioidomycosis, since this gland may be highly compromised in the patients, leading to the development of Addison's Disease.

Propolis effects on pro-inflammatory cytokine production and Toll-like receptor 2 and 4 expression in stressed mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clove and eugenol in noncytotoxic concentrations exert immunomodulatory/anti-inflammatory action on cytokine production by murine macrophages

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)