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The antibacterial and antioxidant activity of the ethanol extract from Paullinia cupana var. sorbilis Mart. (Sapindaceae) seeds, commonly called guarana, was assessed towards selected bacteria as well as in different antioxidant models. The extract, at a concentration between 16 and 128 microg/ml, showed a significant antibacterial effect expressed as minimum inhibitory concentration (MIC) against both Gram-negative and Gram-positive bacteria. In particular, Pseudomonas aeruginosa (MIC=16 microg/ml), Proteus mirabilis (MIC=32 microg/ml), Proteus vulgaris (MIC=32 microg/ml) and Escherichia coli (MIC=32 microg/ml) were the most inhibited. The antioxidant activity was determined by the malonyldialdehyde (MDA) test, measuring the MDA concentration in 3T3-L1 cells after induced cellular damage using ferric ammonium citrate (FAC). The reduction of lipid peroxidation was 62.5% using a guarana extract with a concentration of 2 microg/ml. This effect was dose/dependent. The ethanol extract from Paullinia cupana seeds was analysed by spectrophotometry to determine the concentration of catechol substances after treatment of the extract with p-aminophenol. The total phenolics content in the ethanol extract was also determined spectrophotometrically according to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents (GAE). The concentration of catechol equivalent was 6.06+/-0.13 mg/g (mean+/-S.D.), while the total phenolic content was 8.43+/-0.21 mg/g (mean+/-S.D.). The correlation index between antioxidant activity and catechol content was 0.96.

In the present study we investigated whether apoptosis and phagocytosis are regulated by nuclear factor (NF)-kappaB in a model of chronic inflammation. The subcutaneous implant of lambda-carrageenin-soaked sponges elicited an inflammatory response, characterized by a time-related increase of leukocyte infiltration into the sponge and tissue formation, which was inhibited by simultaneous injection of wild-type oligodeoxynucleotide decoy to NF-kappaB. Molecular and morphological analysis performed on infiltrated cells demonstrated: 1) an inhibition of NF-kappaB/DNA binding activity; 2) an increase of polymorphonuclear leukocyte apoptosis correlated either to an increase of p53 or Bax and decrease of Bcl-2 protein expression; and 3) an increase of phagocytosis of apoptotic polymorphonuclear leukocytes by macrophages associated with an increase of transforming growth factor-beta1 and decrease of tumor necrosis factor-alpha as well as nitrite/nitrate production. Our results, showing that blockade of NF-kappaB by oligodeoxynucleotide decoy increases inflammatory cell apoptosis and phagocytosis, may contribute to lead to new insights into the mechanisms governing the inflammatory process.

Nitric oxide (NO) plays an important role in the pathogenesis of the histological changes seen in coeliac disease. We have investigated the effect of peptic-tryptic digest of gliadin (Pt-G) and gliadin (G) on inducible nitric oxide synthase (iNOS) protein expression in RAW 264.7 macrophages stimulated with interferon-gamma (IFN-gamma). Pt-G and G enhanced in a concentration and time-dependent manner NO production by IFN-gamma-stimulated RAW 264.7 cells. The increase of iNOS protein expression was correlated with NF-kappa B/DNA binding activity and occurred at transcriptional level. Pyrrolidine dithiocarbamate and N-alpha-para-tosyl-L-lysine chloromethyl ketone, two known inhibitors of NF-kappa B activation, decreased significantly NO production and iNOS protein expression as well as NF-kappa B/DNA binding activity. Our results show that the effect of Pt-G and G on enhancement of iNOS protein expression in IFN-gamma-treated RAW 264.7 cells is mainly mediated through NF-kappa B and suggest that blockage of NF-kappa B activation reduces enhancing effect of gluten on NO production in inflamed mucosa of coeliac patients.

NF-kappa B regulates inflammatory and immune response by increasing the expression of specific genes. In celiac disease proinflammatory cytokines, adhesion molecules, and enzymes whose gene expression is known to be regulated by NF-kappa B are involved. This study investigated the activation of NF-kappa B in inflamed mucosa from patients with untreated celiac disease. Biopsy specimens from control, untreated, and treated patients were subjected to molecular biology analysis. NF-kappa B activation was evaluated by electrophoretic mobility shift assay. NF-kappa B related subunit protein level, and inducible nitric oxide synthase and cyclo-oxygenase 2 protein expression was analyzed by western blot. Both NF-kappa B/DNA binding activity and p50/p65 nuclear levels were higher in biopsy specimens from untreated patients than in those from treated patients and controls. The degradation of I kappa B beta in the cytosol and the reappearance in the nucleus indicated a persistent NF-kappa B activation in celiac disease. NF-kappa B activity was maintained in cultured biopsy specimens up to 6 h and decreased at 24 h, and then the addition of peptic-tryptic digest of gliadin caused the recovery of NF-kappa B activity at 6 h. NF-kappa B/DNA binding activity was correlated with inducible nitric oxide synthase and cyclo-oxygenase-2 protein expression. These results show for the first time that NF-kappa B is activated in the inflamed mucosa of celiac patients and suggest that it may represent a molecular target for the modulation of inflammatory response in celiac disease.