Helicobacter pylori is one of major cause of chronic gastritis and peptic ulcer disease, increasing the probability of the onset of stomach cancer if the infection is left untreated. Although the mechanism involved in gastric inflammation by this bacterium is not fully understood, it is known the important role of reactive oxygen species (ROS) produced by polymorphonuclear neutrophils (PMN), which are attracted and activated by infection agent, without, however, to be able to overcome the same, but which contribute strongly to the tissue damage and chronic inflammation. Given this context, molecules with antioxidant properties have been studied as adjuvants in treating this disease, reducing the level of oxidative damage. Among the antioxidants that have been studied, one that has highlighted is the gallic acid and its esters, which in addition to antioxidant properties, has important antimicrobial activity, which is also extremely important to eradicate the H. pylori infection. Therefore, this study will evaluate the antioxidant activity of gallic acid and its semi-synthetic esters about ROS produced in the burst oxidative in PMNs isolated from human blood, by luminol and lucigenin - dependent chemiluminescence assay, as well as the inhibition of the production of hypochlorous acid will be determined by its reaction with taurine, producing taurine chloramine. It will also be evaluated the neutrophils viability after treatment with the selected molecules as well as will be checked its cytoprotective effect about neutrophils activated by PMA. Finally, the anti-Helicobacter pylori activity of gallic acid and its derivatives will be analyzed by the microdilution broth method and determination of minimum inhibitory concentration.
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