Fructooligosaccharides exert intestinal anti-inflammatory activity in the CD4+ CD62L+ T cell transfer model of colitis in C57BL/6J mice.

PURPOSE: Fructooligosaccharides (FOS) are used as functional foods due to their prebiotic effects. Intestinal anti-inflammatory activity has been established in most, but not all, studies in animal models of colitis, using mainly chemically induced inflammation. Our goal was to test the effect of FOS (degree of polymerization 2-8) in the chronic, lymphocyte-driven CD4+ CD62L+ T cell transfer model of colitis. METHODS: Colitis was induced by transfer of CD4+ CD62L+ T cells to C57BL/6J Rag1(-/-) mice. FOS (75 mg day(-1)) was administered by gavage as a post-treatment. Three groups were established: non-colitic (NC), colitic control (C, CD4+ CD62L+ transferred mice treated with vehicle) and colitic+FOS (C+FOS, similar but treated with FOS). Mice were killed after 13 days. RESULTS: Treatment of mice with FOS ameliorated colitis, as evidenced by an increase in body weight, a lesser myeloperoxidase and alkaline phosphatase activities, a lower secretion of proinflammatory cytokines by mesenteric lymph node cells ex vivo (IFN-γ, IL-17, and TNF-α), and a higher colonic expression of occludin (C+FOS vs. C, p < 0.05). Increased relative abundance of lactic acid bacteria was observed in FOS-treated mice (p < 0.05). CONCLUSIONS: FOS exert intestinal anti-inflammatory activity in T lymphocyte-dependent colitis, suggesting it may be useful in the management of inflammatory bowel disease in appropriate conditions.

A new therapeutic association to manage relapsing experimental colitis: Doxycycline plus Saccharomyces boulardii.

Immunomodulatory antibiotics have been proposed for the treatment of multifactorial conditions such as inflammatory bowel disease. Probiotics are able to attenuate intestinal inflammation, being considered as safe when chronically administered. The aim of the study was to evaluate the anti-inflammatory effects of doxycycline, a tetracycline with immunomodulatory properties, alone and in association with the probiotic Saccharomyces boulardii CNCMI-745. Doxycycline was assayed both in vitro (Caco-2 epithelial cells and RAW 264.7 macrophages) and in vivo, in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis and the dextran sodium sulfate (DSS) model of mouse colitis. In addition, the anti-inflammatory effect of the association of doxycycline and the probiotic was evaluated in vitro and in vivo in a DSS model of reactivated colitis in mice. Doxycycline displayed immunomodulatory activity in vitro, reducing IL-8 production by intestinal epithelial cells and nitric oxide by macrophages. Doxycycline administration to TNBS-colitic rats (5, 10 and 25 mg/kg) ameliorated the intestinal inflammatory process, being its efficacy comparable to that previously showed by minocycline. Doxycycline treatment was also effective in reducing acute intestinal inflammation in the DSS model of mouse colitis. The association of doxycycline and S. boulardii helped managing colitis in a reactivated model of colitis, by reducing intestinal inflammation and accelerating the recovery and attenuating the relapse. This was evidenced by a reduced disease activity index, colonic tissue damage and expression of inflammatory mediators. This study confirms the intestinal anti-inflammatory activity of doxycycline and supports the potential use of its therapeutic association with S. boulardii for the treatment of inflammatory bowel diseases, in which doxycycline is used to induce remission and long term probiotic administration helps to prevent the relapses.

Intestinal anti-inflammatory activity of apigenin K in two rat colitis models induced by trinitrobenzenesulfonic acid and dextran sulphate sodium.

Flavonoids are polyphenolic compounds that are widespread in nature, and consumed as part of the human diet in significant amounts. The aim of the present study was to test the intestinal anti-inflammatory activity of apigenin K, a soluble form of apigenin, in two models of rat colitis, namely the trinitrobenzenesulfonic acid (TNBS) model and the dextran sulphate sodium (DSS) model. Apigenin K (1, 3 and 10 mg/kg; by the oral route; n 4-6 per group) was administered as a pre-treatment to rats with TNBS and DSS colitis, and colonic status was checked by macroscopic and biochemical examination. Apigenin K pre-treatment resulted in the amelioration of morphological signs and biochemical markers in the TNBS model. The results demonstrated a reduction in the inflamed area, as well as lower values of score and colonic weight:length ratio compared with the TNBS group. Myeloperoxidase (MPO) activity was reduced by 30 % (P< 0·05). Moreover, apigenin K pre-treatment ameliorated morphological signs and biochemical markers in the DSS model. Thus, macroscopic damage was significantly reduced and the colonic weight:length ratio was lowered by approximately 10 %, while colonic MPO and alkaline phosphatase activities were decreased by 35 and 21 %, respectively (P< 0·05). Apigenin K pre-treatment also tended to normalise the expression of a number of colonic inflammatory markers (e.g. TNF-α, transforming growth factor-ß, IL-6, intercellular adhesion molecule 1 or chemokine (C-C motif) ligand 2). In conclusion, apigenin K is found to have anti-inflammatory effects in two preclinical models of inflammatory bowel disease.

Rutin has intestinal antiinflammatory effects in the CD4+ CD62L+ T cell transfer model of colitis.

Rutin, one of the most abundant flavonoids in nature, has been shown to exert intestinal antiinflammatory effects in experimental models of colitis. Our aim was to study the antiinflamatory effect of rutin in the CD4+ CD62L+ T cell transfer model of colitis, one of the closest to the human disease. Colitis was induced by transfer of CD4+ CD62L+ T cells to Rag1(-/-) mice. Rutin was administered by gavage as a postreatment. Treatment with rutin improved colitis at the dose of 57mg/kg/day, while no effect was noted with 28.5mg/kg/day. Therapeutic benefit was evidenced by a reduced disease activity index, weight loss and damage score, plus a 36% lower colonic myeloperoxidase and a 54% lower alkaline phosphatase activity. In addition, a decreased secretion of proinflammatory cytokines (IFNγ and TNFα) by mesenteric lymph node cells was observed ex vivo. The colonic expression of proinflammatory genes, including IFNγ, TNFα, CXCL1, S100A8 and IL-1ß, was significantly reduced by more than 80% with rutin as assessed by RT-qPCR. Flavonoid treated mice exhibited decreased activation of splenic CD4+ cells (STAT4 phosphorylation and IFNγ expression) and reduced plasma cytokine levels. This effect was also apparent in mucosal lymphocytes based on reduced STAT4 phosphorylation. The protective effect was comparable to that of 3mg/kg/day budesonide. Rutin had no effect on splenocytes or murine T cells in vitro, while its aglycone, quercetin, exhibited a concentration dependent inhibition of proinflammatory cytokines, including IFNγ. Rutin but not quercetin showed vectorial basolateral to apical transport in IEC18 cells, associated with reduced biotransformation. We conclude that rutin exerts intestinal antiinflammatory activity in chronic, T lymphocyte dependent colitis via quercetin release and actions involving mucosal and lymph node T cells. Our results suggest that rutin may be useful in the management of inflammatory bowel disease in appropriate dosage conditions.

Validation of bovine glycomacropeptide as an intestinal anti-inflammatory nutraceutical in the lymphocyte-transfer model of colitis.

Milk κ-casein-derived bovine glycomacropeptide (GMP) exerts immunomodulatory effects. It exhibits intestinal anti-inflammatory activity in chemically induced models of colitis. However, to validate its clinical usefulness as a nutraceutical, it is important to assess its effects in a model with a closer pathophysiological connection with human inflammatory bowel disease. Therefore, in the present study, we used the lymphocyte-transfer model of colitis in mice and compared the effects of GMP in this model with those obtained in the dextran sulphate sodium (DSS) model. GMP (15 mg/d) resulted in higher body-weight gain and a reduction of the colonic damage score and myeloperoxidase (MPO) activity in Rag1(-/-) mice with colitis induced by the transfer of naïve T cells. The colonic and ileal weight:length ratio was decreased by approximately 25%, albeit non-significantly. GMP treatment reduced the percentage of CD4⁺ interferon (IFN)-γ⁺ cells in mesenteric lymph nodes (MLN). The basal production of IL-6 by MLN obtained from the GMP-treated mice ex vivo was augmented. However, concanavalin A-evoked production was similar. The colonic expression of regenerating islet-derived protein 3γ, S100A8, chemokine (C-X-C motif) ligand 1 and IL-1ß was unaffected by GMP, while that of TNF-α and especially IFN-γ was paradoxically increased. In the DSS model, GMP also reduced the activity of colonic MPO, but it failed to alter weight gain or intestinal weight:length ratio. GMP augmented the production of IL-10 by MLN cells and was neutral towards other cytokines, except exhibiting a trend towards increasing the production of IL-6. The lower effect was attributed to the lack of the effect of GMP on epithelial cells. In conclusion, GMP exerts intestinal anti-inflammatory effects in lymphocyte-driven colitis.

Negative clinical outcomes of medication resulting in emergency department visits.

PURPOSE: The results of analyses of patients' health problems related to medication use have been highly variable due to various factors, such as different study methodology, diverse variables determined, fields of study. The aim of our study was to determine the prevalence and preventability of negative clinical outcomes of medication (NCOMs). METHODS: This was a cross-sectional study performed in the emergency departments (EDs) of nine Spanish hospitals during a 3-month period. A two-stage probabilistic sampling method was used , and a systematic appraisal tool was used to identify the NCOMs based on information gathered through patient interview and review of the medical records. Case evaluations were conducted in two phases by pharmacists and physicians. The prevalence and preventability of NCOM were calculated. A homogeneity test was performed to assess potential differences in the prevalence for each hospital. RESULTS: A total of 4,611 patients were included in the study. The overall prevalence of NCOMs was 35.7 % [95 % confidence interval (CI) 33.3-38.1]. These NCOMs could be divided into three categories: ineffectiveness (18.2 %; 95 % CI 16.2-20.1), necessity (14.9 %; 95 % CI 13.4-16.6), and lack of safety (2.4 %; 95 % CI 1.9-2.8). About 81 % (95 % CI 80.1-82.3) of the NCOMs could have been prevented. CONCLUSIONS: NCOMs provoked approximately one-third of visits to the EDs, and a high percentage of these were preventable. Implementation of strategies for patient safety and pharmaceutical care could help to prevent these problems and optimize the use of medications.

Active colitis exacerbates immune response to internalized food antigens in mice.

BACKGROUND: Previous studies have indicated that colitis increases intestinal permeability to food antigens. This condition also generates an immunoreactive milieu in the gut, which may exacerbate or counteract allergy reactions. This, along with the fact that both colitis and allergy are being codiagnosed more frequently, means the scientific interest on the immune relation between these pathologies is increasing. We evaluated the immune response to an internalized food antigen that was initiated during a concomitant active intestinal inflammatory response. METHODS: An ovalbumin (OVA)-induced immune response was analyzed in healthy mice and in mice suffering from colitis induced by the administration of dinitrofluorobenzene/dinitrosulfonic acid (DNFB/DNS) at the moment of OVA challenge. The OVA-induced clinical score and allergy response both in plasma and in splenocyte cultures from these animals were compared. RESULTS: Although no differences were observed in the allergy clinical score, the concomitant active colitis led to an increase in the immune response to OVA antigen, as shown by increased spleen size and OVA-induced splenocyte proliferation, exacerbated expression of total and OVA-specific IgG1 levels, increased colonic IL-4 expression and OVA-induced IL-4 and IL-5 cytokine expression in spleen cells. CONCLUSIONS: Our results indicate that animals with active colitis undergo an exacerbated immune response to an internalized antigen. This finding could be relevant for the allergy management of patients presenting simultaneously with chronic colitis.

Active hexose-correlated compound and Bifidobacterium longum BB536 exert symbiotic effects in experimental colitis.

PURPOSE: Active hexose-correlated compound (AHCC) is a commercial extract obtained from Basidiomycetes under controlled conditions, yielding a 74 % content in oligosaccharides, especially α-glucans. AHCC has a number of therapeutic effects, including intestinal anti-inflammatory activity. Bifidobacterium longum BB536 is a probiotic with potential health-promoting effect at the gut level. The purpose of the present study was to evaluate the possibility of synergism between AHCC, which is believed to act as a prebiotic, and B. longum BB536. METHODS: We used the trinitrobenzene sulfonic acid model (TNBS) of colitis in rats. AHCC (100 or 500 mg kg(-1)) and B. longum BB536 (5 × 10(6) CFU rat(-1) day(-1)) were administered together or separately for 7 days prior to colitis induction and then for another 7 days and compared with control (noncolitic) and TNBS rats. RESULTS: The results show that both treatments had intestinal anti-inflammatory activity separately, which was enhanced when used in combination, as shown by changes in body weight gain, colonic weight to length ratio, myeloperoxydase activity and iNOS expression. Interestingly, the association of AHCC 100 mg kg(-1) + B. longum BB536 showed the highest anti-inflammatory activity. CONCLUSIONS: Our data provide a preclinical experimental basis for the synergistic effect of AHCC and B. longum BB536 on inflammatory bowel disease.

The immunomodulatory properties of viable Lactobacillus salivarius ssp. salivarius CECT5713 are not restricted to the large intestine.

PURPOSE: The aim of this study was to better characterise the biological effects of Lactobacillus salivarius ssp. salivarius CECT5713, a probiotic with immunomodulatory properties. METHODS: Live or dead probiotic was assayed in the TNBS model of rat colitis to determine whether viability was a requisite to exert the beneficial effects. In vitro studies were also performed in Caco-2 cells to evaluate its effects on epithelial cell recovery and IL-8 production. Finally, the probiotic was assayed in the LPS model of septic shock in mice to establish its effects when there is an altered systemic immune response. RESULTS: The viability of the probiotic was required for its anti-inflammatory activity. The probiotic inhibited IL-8 production in stimulated Caco-2 cells and facilitated the recovery of damaged intestinal epithelium. In LPS-treated mice, the probiotic inhibited the production of TNFα in plasma and lungs and increased the hepatic glutathione content. These effects were associated with an improvement in the altered production of the T-cell cytokines in splenocytes, by reducing IL-2 and IL-5 and by increasing IL-10. Finally, it reduced the increased plasma IgG production in LPS-treated mice. CONCLUSION: The anti-inflammatory effects of viable L. salivarius ssp. salivarius CECT5713 are not restricted to the gastrointestinal tract.

Intestinal inflammation and the enterocyte transportome.

Diarrhoea is a hallmark of intestinal inflammation. The mechanisms operating in acute inflammation of the intestine are well characterized and are related to regulatory changes induced by inflammatory mediators such as prostaglandins, cytokines or reactive oxygen species, along with leakage due to epithelial injury and changes in permeability. In chronic colitis, however, the mechanisms are less well known, but it is generally accepted that both secretory and absorptive processes are inhibited. These disturbances in ionic transport may be viewed as an adaptation to protracted inflammation of the intestine, since prolonged intense secretion may be physiologically unacceptable in the long term. Mechanistically, the changes in transport may be due to adjustments in the regulation of the different processes involved, to broader epithelial alterations or frank damage, or to modulation of the transportome in terms of expression. In the present review, we offer a summary of the existing evidence on the status of the transportome in chronic intestinal inflammation.

The intestinal anti-inflammatory effect of minocycline in experimental colitis involves both its immunomodulatory and antimicrobial properties.

Some antibiotics, including minocycline, have recently been reported to display immunomodulatory properties in addition to their antimicrobial activity. The use of a compound with both immunomodulatory and antibacterial properties could be very interesting in the treatment of inflammatory bowel disease (IBD), so the aim of our study was to evaluate the anti-inflammatory effect of minocycline in several experimental models of IBD. Firstly, the immunomodulatory activity of the antibiotic was tested in vitro using Caco-2 intestinal epithelial cells and RAW 264.7 macrophages; minocycline was able to inhibit IL-8 and nitrite production, respectively. In vivo studies were performed in trinitrobenzenesulfonic acid (TNBS)-induced rat colitis and dextran sodium sulfate (DSS)-induced mouse colitis. The results revealed that minocycline exerted an intestinal anti-inflammatory effect when administered as a curative treatment in the TNBS model, modulating both immune and microbiological parameters, being confirmed in the DSS model; whereas none of the other antibiotics tested (tetracycline and metronidazole) showed anti-inflammatory effect. However, minocycline administration before the colitis induction was not able to prevent the development of the intestinal inflammation, thus showing that only its antimicrobial activity is not enough for the anti-inflammatory effect. In conclusion, minocycline displays an anti-inflammatory effect on different models of rodent colitis which could be attributed to the association of its antibacterial and immunomodulatory properties.

Endothelium-dependent vasodilator effects of peroxisome proliferator-activated receptor beta agonists via the phosphatidyl-inositol-3 kinase-Akt pathway.

Peroxisome proliferator-activated receptor beta/delta (PPAR-beta) is a ligand-activated transcription factor belonging to the nuclear hormone receptor superfamily that regulates the transcription of many target genes. More recently, acute, nongenomic effects of PPAR-beta agonists have also been described. In the present study, we hypothesized that PPAR-beta agonists might exert acute nongenomic effects on vascular tone. Here, we report that the structurally unrelated PPAR-beta ligands [4-[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propoxy]phenoxy]acetic acid (L-165041) and 4-[[[2-[3-fluoro-4-(trifluoromethyl)phenyl]-4-methyl-5-thiazolyl] methyl]thio]-2-methylphenoxy]acetic acid (GW0742) induced vascular relaxation in phenylephrine-precontracted endothelium-intact rat aortic rings, which was significantly inhibited by endothelial denudation or nitric-oxide synthase (NOS) inhibition with N(G)-nitro-l-arginine methylester. These relaxant effects reached steady state within 15 min. The relaxation induced by L-165041 and GW0742 in aortic rings precontracted with the thromboxane A(2) analog 9,11-dideoxy-11alpha,9alpha-epoxymethanoprostaglandin F2alpha (U-46619) was unaffected either by removal of extracellular calcium or by incubation with calcium-free solution containing the intracellular calcium chelator 1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetra(acetoxymethyl) ester. However, the phosphatidylinositol 3-kinase (PI3K) inhibitor 2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one hydrochloride (LY-294002) inhibited the endothelium-dependent relaxant responses induced by both PPAR-beta agonists. Blockade of PPAR-beta with 3-[[[2-methoxy-4-(phenylamino)phenyl]amino]sulfonyl]-2-thiophenecarboxylic acid methyl ester (GSK0660) also partially inhibited these relaxant responses, although PPAR-gamma blockade with 2-chloro-5-nitro-N-phenylbenzamide (GW9662) had no effect. In human umbilical vein endothelial cells, L-165041 and GW0742 increased nitric oxide (NO) production and Akt and endothelial NOS (eNOS) phosphorylation, which were sensitive to PI3K inhibition and PPAR-beta blockade. In conclusion, the PPAR-beta agonists acutely caused vasodilatation, which was partially dependent on endothelial-derived NO. The eNOS activation is calcium-independent and seems to be related to activation of the PI3K-Akt-eNOS pathway.

Bovine glycomacropeptide has intestinal antiinflammatory effects in rats with dextran sulfate-induced colitis.

Milk κ-casein-derived bovine glycomacropeptide (GMP) has immunomodulatory and bacterial toxin-binding effects, and it has been shown to exert intestinal antiinflammatory activity in the trinitrobenzenesulfonic acid-induced model of colitis. However, its mechanism of action is not well characterized, and it is not known whether GMP is effective in other experimental models. The intestinal antiinflammatory activity of GMP was assessed in the dextran sulfate sodium (DSS)-induced model of rat colitis. DSS was applied at a starting concentration of 5% (wt:v) in drinking water and adjusted when the disease activity index (DAI) increased substantially for 10 d. There were 3 experimental groups: control (no inflammation), DSS, and GMP (GMP-treated rats with DSS-induced colitis). GMP pretreatment (500 mg · kg(-1) · d(-1), starting 2 d before DSS treatment) reduced the DAI by 60% and lowered the colonic damage score by 44% (P < 0.05). GMP fully normalized the colonic expression of interleukin (IL) 1ß, IL17, IL23, IL6, transforming growth factor ß, IL10, and Foxp3 as assessed by quantitative RT-PCR. The production of interferon-γ by mesenteric lymph node cells ex vivo was also normalized by GMP treatment. In contrast, GMP did not change colonic thickening, myeloperoxidase, cyclooxygenase 2, or alkaline phosphatase. Histology analysis showed better preservation of the epithelium and attenuated infiltration and submucosal thickening in rats treated with GMP. We conclude that GMP exerts intestinal antiinflammatory activity in this model, which may be primarily related to actions on Th1 and Th17 lymphocytes and perhaps macrophages.

Reversible Ponceau staining as a loading control alternative to actin in Western blots.

It is becoming standard practice to measure a housekeeping gene, typically actin, in Western blots, as it is the rule in RNA blots. We have applied reversible Ponceau staining to check equal loading of gels and measured actin in parallel under different conditions. Our results show that densitometric analysis is comparable with both techniques. Therefore, routine quantitation of Ponceau staining before antibody probing is validated as an alternative to actin blotting.

Evaluation of the preventative effects exerted by Lactobacillus fermentum in an experimental model of septic shock induced in mice.

The preventative effects of the probiotic Lactobacillus fermentum CECT5716 were evaluated in the lipopolysaccharide (LPS) model of septic shock in mice. The probiotic was administered suspended in drinking water at the final concentration of 108 colony-forming units/ml for 2 weeks before the induction of an endotoxic shock by an intraperitoneal injection of LPS (400 microg/200 microl per mouse). Blood and different organs were collected after 24 h to evaluate the severity of the endotoxic shock and the preventative effects of the probiotic. L. fermentum reduced TNF-alpha levels in blood, which promotes the major alterations observed during septic shock, as well as the infiltration of activated neutrophils into the lungs. Furthermore, free radical overproduction and oxidative stress were associated with a significant decrease in hepatic glutathione levels in septic mice, and with an excessive NO production attributed to the induction of the inducible isoform of NO synthase (iNOS). In fact, hepatic glutathione levels were significantly increased in the group of mice receiving the probiotic, and the increased iNOS expression both in the colon and lungs was down-regulated in those mice treated with L. fermentum. Finally, pre-treatment with L. fermentum may also exert its protective action modulating the expression of different cytokines in splenocyte-derived T cells such us IL-2, IL-5, IL-6 or IL-10. In conclusion, pre-treatment with L. fermentum may exert its protective action against LPS-induced organ damage in mice by a combination of several actions including its antioxidant properties and by reduction of the synthesis of the pro-inflammatory TNF-alpha and IL-6.

Disturbances in metabolic, transport and structural genes in experimental colonic inflammation in the rat: a longitudinal genomic analysis.

BACKGROUND: Trinitrobenzenesulphonic acid (TNBS) induced rat colitis is one of the most widely used models of inflammatory bowel disease (IBD), a condition whose aetiology and pathophysiology are incompletely understood. We have characterized this model at the genomic level using a longitudinal approach. Six control rats were compared with colitic animals at 2, 5, 7 and 14 days after TNBS administration (n = 3). The Affymetrix Rat Expression Array 230 2.0 system was used. RESULTS: TNBS-induced colitis had a profound impact on the gene expression profile, which was maximal 5 and 7 days post-induction. Most genes were affected at more than one time point. They were related to a number of biological functions, not only inflammation/immunity but also transport, metabolism, signal transduction, tissue remodeling and angiogenesis. Gene changes generally correlated with the severity of colitis. The results were successfully validated in a subset of genes by real-time PCR. CONCLUSION: The TNBS model of rat colitis has been described in detail at the transcriptome level. The changes observed correlate with pathophysiological disturbances such as tissue remodelling and alterations in ion transport, which are characteristic of both this model and IBD.

Effects of dietary fibers on disturbances clustered in the metabolic syndrome.

Because of its growing prevalence in Western countries, the metabolic syndrome, a common metabolic disorder that clusters a constellation of abnormalities, including central obesity, hypertension, dyslipidemia and insulin resistance, is emerging as one of the most important public health problems in the world, taking into account that it is a major risk factor mainly for type 2 diabetes and cardiovascular diseases, and also for many types of cancer. Although the pathogenesis of this syndrome is complex and not fully understood, obesity and insulin resistance, accompanied by an altered profile of number of hormones and cytokines produced by the adipose tissue, seem to be the main causative agents. A prime therapeutic approach to the prevention and treatment of this syndrome involves lifestyle changes. Among dietary modifications, dietary fiber intake could play an interesting role in the management of metabolic syndrome through different mechanisms related to its dietary sources, specific chemical structure and physical properties, or fermentability in the gut. According to all of these variables, the different types of dietary fibers have been reported to take part in the control of body weight, glucose and lipid homeostasis, insulin sensitivity and in the regulation of many inflammation markers involved in the pathogenesis of metabolic syndrome, and which are also considered to be among its features.

Baseline glutathione peroxidase activity affects prognosis after acute coronary syndromes.

Oxidative stress is associated with atherosclerosis and plaque lesions in experimental in vitro models. Few in vivo studies have examined the association between redox status and the prognosis of acute coronary syndromes.We undertook a prospective, observational study of 137 patients who had been admitted because of an acute coronary syndrome. We determined glutathione peroxidase activity (a marker of systemic antioxidant status) and recorded clinical and angiographic features and cardiovascular events (cardiovascular death, reinfarction, readmission with a new ischemic event, or need for coronary revascularization).The mean age of the patients (78% of whom were men) was 61.7 +/- 10.9 years; 76% were admitted with non-ST-segment-elevation acute coronary syndrome. Left ventricular ejection fraction was normal in 61%. In the 23.4% who experienced cardiovascular events, glutathione peroxidase activity was higher (mean, 2.38 vs 1.76 mU/mg of protein; P < 0.01). Two-year event-free survival was lower in patients whose glutathione peroxidase activity was higher than the 50th percentile (63% vs 82%; P = 0.01). Multivariate analysis showed a direct independent relationship between glutathione peroxidase activity and cardiovascular events (hazard ratio, 3.72; 95% confidence interval, 1.53-9.02; P < 0.01).We conclude that patients who experienced acute coronary syndromes and events during follow-up had higher plasma glutathione peroxidase activity, and that glutathione peroxidase activity was an independent predictor of events during follow-up.

Calprotectin protects against experimental colonic inflammation in mice.

BACKGROUND AND PURPOSE: Calprotectin is a heterodimer composed of two myeloid-related proteins, S100A8 and S100A9, that is abundant in neutrophils and monocytes/macrophages. Faecal levels of calprotectin are used routinely to monitor inflammatory bowel disease activity. EXPERIMENTAL APPROACH: We aimed to assess the role of calprotectin in intestinal inflammation, using the dextran sulfate sodium model of colitis in mice. Calprotectin was administered (50 or 100 µg·day-1 ) by the intrarectal or by i.p. injection (50 µg·day-1 only). The condition of the mice was characterized by morphological and biochemical methods. KEY RESULTS: Intrarectal calprotectin protected significantly against colitis, as shown by lower levels of macroscopic and microscopic damage, colonic myeloperoxidase activity and decreased expression of TNFα and toll-like receptor 4. IL-17 production by spleen and mesenteric lymph node cells was reduced. Calprotectin had no effect on body weight loss or colonic thickening. There were no effects of calprotectin after i.p. injection. Calprotectin had virtually no effects in control, non-colitic mice. Calprotectin had almost no effect on the colonic microbiota but enhanced barrier function. Treatment of rat IEC18 intestinal epithelial cells in vitro with calprotectin induced output of the chemokines CXL1 and CCL2, involving the receptor for advanced glycation end products- and NFκB. CONCLUSION AND IMPLICATIONS: Calprotectin exerted protective effects in experimental colitis when given by the intrarectal route, by actions that appear to involve effects on the epithelium.

Polyphenols restore endothelial function in DOCA-salt hypertension: role of endothelin-1 and NADPH oxidase.

Red wine polyphenols (RWPs) have been reported to exert beneficial effects in preventing cardiovascular diseases, such as hypertension. We studied the effects of chronic treatment with RWPs and apocynin, an inhibitor of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, on blood pressure, endothelial function, and oxidative status in deoxycorticosterone acetate (DOCA)-salt-induced hypertension. Rats were administered RWPs (40 mg/kg) or apocynin (33 microg/kg) daily by gavage for 5 weeks. Plasma catechin levels were detected only after RWP treatment. RWPs and apocynin prevented both the increase in systolic blood pressure and the proteinuria induced by DOCA-salt. Plasma malonyldialdehyde levels, urinary iso-prostaglandin F(2alpha) excretion, aortic superoxide production, and aortic NADPH oxidase activity were found to be increased in animals of the DOCA group. RWP and apocynin treatments reduced these parameters in DOCA-salt rats, having no effect on control rats. However, only RWPs reduced the increase in plasma endothelin-1 (ET-1) levels and aortic p22(phox) gene overexpression found in DOCA-salt animals. RWPs and apocynin also improved the blunted endothelium-dependent relaxation response to acetylcholine in noradrenaline-precontracted aortic rings. All these results suggest that chronic treatment with RWPs prevents hypertension and vascular dysfunction. RWPs prevent vascular oxidative stress by inhibiting NADPH oxidase activity and/or by reducing ET-1 release.