21 research outputs found

    Protection against Chemotaxis in the Anti-Inflammatory Effect of Bioactives from Tomato Ketchup

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    The consumption of tomato products has been associated with a decreased risk for chronic inflammatory diseases. In this study, the anti-inflammatory potential of tomato ketchup was evaluated by studying the effect of tomato ketchup extracts and bioactives from tomato ketchup on human monocytes and vascular endothelial cells (HUVEC). HUVEC were pre-treated for 1 h with either individual bioactives (7.5 µM lycopene, 1.4 µM α-tocopherol or 55 µM ascorbic acid) or a combination of these three compounds, or with the hydrophilic or lipophilic tomato ketchup extracts or with the two extracts combined. After the pretreatment, the cells were washed and challenged with TNF-α (10 ng/ml) for 6 h. The medium was used for the determination of the release of cytokines and the chemotaxis of monocytes. Inflammatory protein expression and production were assayed with real-time RT-PCR and ELISA. It was found that tomato ketchup extracts significantly reduced gene expression and release of the pro-inflammatory cytokines TNF-α and IL-8 in HUVEC after the inflammatory challenge, whereas the release of the anti-inflammatory cytokine IL-10 was increased. Chemotaxis was effectively impeded as demonstrated by a reduced monocyte migration. This effect correlated with the reduction of IL-8 production in the presence of the test compounds and extracts. The results consistently emphasize the contribution of lycopene to the anti-inflammatory effect of tomato ketchup. Other compounds in tomato ketchup such as α-tocopherol and ascorbic acid appeared to strengthen the anti-inflammatory effect of lycopene. The tomato ketchup extracts subtly interfered with several inflammatory phases that inhibit chemotaxis. Such a pleotropic mode of action exemplifies its potential mitigation of diseases characterized by prolonged low grade inflammation

    Variant VKORC1 and CYP2C9 Alleles in Patients with Diffuse Alveolar Hemorrhage Caused by Oral Anticoagulants

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    Diffuse alveolar hemorrhage (DAH) is a life-threatening bleeding complication that can occur as a result of oral anticoagulation therapy. We hypothesized that in patients treated with coumarins, alveolar hemorrhage is associated with vitamin K epoxide reductase (VKORC1) and cytochrome P450 (CYP) 2C9 (CYP2C9) variant alleles. In addition, in the case of acenocoumarol use, CYP2C19 allelic variants also play a role. During a 7-year period, data on patients using coumarins with confirmed DAH were gathered. Of 173 confirmed DAH cases, 75 received oral anticoagulants, and 63 (84%) of these 75 patients were included because their DNA was available. For genotyping the CYP2C9*2 (430C>T), CYP2C9*3 (1075A>C), CYP2C19*2 (681G>A), CYP2C19*3 (636G>A), VKORC1 (-1639G>A), and VKORC1 (1173C>T) single nucleotide polymorphisms (SNPs), real-time PCRs were performed. In 62 (98.4%) of 63 patients with DAH, variant alleles were found. In 51 (81.0%) of the 63 patients, VKORC1 allelic variants (20 homozygotes and 31 heterozygotes) were present. In 31 (49.2%) of the 63 DAH cases, CYP2C9 allelic variants (three homozygotes, 26 heterozygotes, and two compound heterozygotes) were observed, and in 20 (32.0%) of the 63 patients, variant alleles of both genes were observed. Genotyping of four SNPs for VKORC1 and CYP2C9 polymorphisms is useful in predicting a high probability of the occurrence of DAH in patients receiving oral anticoagulants. Early and timely use of genotyping is recommended to prevent a fatal outcome and to provide safer and more individualized anticoagulant therapy

    Food-Derived Bioactives Can Protect the Anti-Inflammatory Activity of Cortisol with Antioxidant-Dependent and -Independent Mechanisms

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    In chronic inflammatory diseases the anti-inflammatory effect of glucocorticoids (GCs) is often decreased, leading to GC resistance. Inflammation is related with increased levels of reactive oxygen species (ROS), leading to oxidative stress which is thought to contribute to the development of GC resistance. Plant-derived compounds such as flavonoids are known for their ability to protect against ROS. In this exploratory study we screened a broad range of food-derived bioactives for their antioxidant and anti-inflammatory effects in order to investigate whether their antioxidant effects are associated with the ability to preserve the anti-inflammatory effects of cortisol. The anti-inflammatory potency of the tested compounds was assessed by measuring the oxidative stress–induced GC resistance in human macrophage-like cells. Cells were pre-treated with H2O2 (800 µM) with and without bioactives and then exposed to lipopolysaccharides (LPS) (10 ng/mL) and cortisol (100 nM). The level of inflammation was deducted from the concentration of interleukin-8 (IL-8) in the medium. Intracellular oxidative stress was measured using the fluorescent probe 2′,7′-dichlorofluorescein (DCFH). We found that most of the dietary bioactives display antioxidant and anti-inflammatory action through the protection of the cortisol response. All compounds, except for quercetin, revealing antioxidant activity also protect the cortisol response. This indicates that the antioxidant activity of compounds plays an important role in the protection of the GC response. However, next to the antioxidant activity of the bioactives, other mechanisms also seem to be involved in this protective, anti-inflammatory effect

    Antioxidant status associated with inflammation in sarcoidosis: A potential role for antioxidants

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    SummaryRationaleEnhanced production of reactive oxygen species (ROS), capable of reducing endogenous defense levels and enhancing inflammation, is suggested to play a role in sarcoidosis. Antioxidant supplementation might offer protection against such ROS-mediated damage. A promising candidate for antioxidant supplementation is the flavonoid quercetin.AimTo determine the antioxidant and inflammatory status in sarcoidosis. Furthermore, the potential of quercetin to mitigate the occurring inflammation will be assessed.MethodsNon-smoking sarcoidosis patients and healthy controls matched for age, gender and dietary behavior were enrolled (NCT-00512967). Measurements included assessment of total plasma antioxidant capacity, vitamin C, uric acid, glutathione, basal and LPS-induced levels of tumor necrosis factor alpha (TNFα), interleukin (IL)-8 and -10 as well as the effect of quercetin on these levels.ResultsCompared to their controls, the sarcoidosis patients displayed significantly lower total plasma antioxidant capacity, decreased levels of vitamin C, uric acid and glutathione and increased levels of basal TNFα and IL-8. Quercetin significantly decreased ex vivo LPS-induced TNFα- and IL-8 production in a concentration-dependent manner in both groups. Interestingly, this quercetin effect was more pronounced in sarcoidosis patients.DiscussionThe endogenous antioxidant defense was significantly reduced in sarcoidosis, indicating that oxidative stress underlies the pathology of this disease. Furthermore, the inflammatory status was significantly enhanced in sarcoidosis. Finally, our results regarding the effect of quercetin on cytokine production imply that sarcoidosis patients might benefit from antioxidant supplementation not only by empowering the relatively low protection against ROS but also by reducing inflammation

    Oxidative stress reduces the muscarinic receptor function in the urinary bladder

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    AIMS: Several pathophysiological conditions in the urinary bladder, for example, ischemia/reperfusion and inflammation are characterized by the formation of reactive oxygen species (ROS). The ROS are highly toxic because they can destroy proteins, DNA, and lipids. The aim of this study was to investigate the effect of oxidative stress on excitation-contraction coupling of detrusor smooth muscle. MATERIALS AND METHODS: Smooth muscle strips were dissected from pig urinary bladder and mounted in organ baths. Oxidative stress was mimicked by the addition of Cumene hydroperoxide (CHP), a lipophilic hydroperoxide, to the organ baths. Contractile responses to electrical field stimulation (EFS: 4-32 Hz), carbachol (10(-8)-3 x 10(-5) M), potassium (65.3 mM), and ATP (1 mM) were monitored before and after the addition of CHP. RESULTS: Responses of detrusor strips to EFS were for the greater part based on neurogenic stimulation and the release of acetylcholine. CHP diminished contractile responses to EFS and carbachol to the same extent. The pD(2) value of the carbachol concentration-response curve decreased significantly after exposure to 0.1 mM, 0.4 mM, 0.8 mM CHP. Furthermore the maximal effect obtained with carbachol was significantly reduced after 0.1 mM, 0.4 mM, and 0.8 mM CHP treatment. Contractions induced by potassium and ATP were significantly less affected by oxidative stress compared to EFS- and carbachol-induced responses of comparable amplitude. CONCLUSIONS: The results of our study demonstrate that oxidative stress induced by CHP affects pig bladder contractility. The muscarinic receptor signaling system is severely damaged. L-type calcium channels and the contractile system are less affected and cholinergic nerves remain largely unaffected. Neurourol. Urodynam. (c) 2006 Wiley-Liss, Inc

    Role of cytochrome p450 polymorphisms in the development of pulmonary drug toxicity: a case-control study in the Netherlands

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    BACKGROUND: Drug-induced pulmonary toxicity is a serious and expanding problem with often unknown aetiology. Many drugs are metabolized by cytochrome P450 (CYP) enzymes. OBJECTIVE: To establish whether allelic variation in CYP polymorphic genes contributes to variability in drug response and unexpected toxicity. METHODS: A case-control study was conducted. The cases consisted of patients with drug-induced interstitial lung disease (DI-ILD; n = 59). Two control groups were used: one group of healthy volunteers (n = 173) and one group of patients with idiopathic pulmonary fibrosis (IPF; n = 110). RESULTS: Of the patients with DI-ILD 91.5% (54/59) had at least one of the studied variant genes compared with 70.5% (122/173, p < 0.001) of the healthy volunteers and 69.1% (76/110, p < 0.001) of the IPF patients. The percentage of individuals with one or more variant CYP genes was higher in the DI-ILD group. Odds ratios were significantly increased and ranged from 3.25 to 40.8, indicating a significant association between the development of DI-ILD and the presence of one or more variant CYP genes. CONCLUSION: DI-ILD appeared to be associated with the presence of at least one variant CYP allele. This study supports the potential usefulness of personalized medicine by genotyping aiming to improve efficacy, tolerability and drug safety. AD - Department of Clinical Chemistry, Maastricht University Medical Centre, Maastricht, the Netherlandsild care center, Maastricht University Medical Centre, Maastricht, the Netherlands

    Genotoxic effects of neutrophils and hypochlorous acid

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    Chronic inflammation has been recognized as a contributing factor in the pathogenesis of lung cancer. In this process, reactive oxygen species released by neutrophils may play an important role. The aim of the present study was to investigate the capacity of the major neutrophilic oxidant hypochlorous acid (HOCl), which is formed by myeloperoxidase (MPO), to induce DNA damage and mutagenicity in lung cells. HOCl was mutagenic in lung epithelial A549 cells in vitro, showing at physiological concentrations a significant induction of mutations in the HPRT gene. We studied three major types of DNA lesions that could be relevant for this HOCl-induced mutagenicity. Single strand DNA breakage and 8-oxo-7,8-dihydro-2'-deoxyguanosine were not found to be increased following HOCl treatment. On the other hand, HOCl caused a significant increase in the formation of 3-(2-deoxy-beta-D-erythro-pentofuranosyl)pyrimido[1,2-alpha]purin-10(3H)-one (M(1)dG), which can be formed by either malondialdehyde (MDA) or base propenals. We observed an increased MDA formation upon exposure of A549 cells to HOCl, but a role of base propenals cannot be excluded. In line with this, we observed 4-fold increased M(1)dG adduct levels in mice that were intratracheally instilled with lipopolysaccharide to induce a pulmonary inflammation with neutrophil influx. Depletion of circulating neutrophils significantly reduced pulmonary MPO activity as well as M(1)dG adducts levels, thereby providing a causal link between neutrophils/HOCl and pulmonary genotoxicity in vivo. Taken together, these data indicate that MPO catalysed formation of HOCl during lung inflammation should be considered as a significant source of neutrophil-induced genotoxicity
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