{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T10:37:11Z","timestamp":1791110231895,"version":"4.1.0"},"reference-count":52,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,20]],"date-time":"2021-12-20T00:00:00Z","timestamp":1639958400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministry of Economy, Industry and Competitiveness","doi-asserted-by":"publisher","award":["AGL2017-89566-R"],"award-info":[{"award-number":["AGL2017-89566-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Helicobacter pylori (H. pylori) is one of the major human pathogens and the main cause of pathological damages that can progress from chronic gastritis to gastric cancer. During the colonization of gastric mucosa, this bacterium provokes a strong inflammatory response and subsequent oxidative process, which are associated with tissue damage. Therefore, the objective of this research was to evaluate the ability of two olive-leaf extracts (E1 and E2) to modulate the inflammatory response and oxidative stress in H. pylori-infected human gastric AGS cells. The obtained results showed that both extracts significantly decreased interleukin-8 (IL-8) secretion and reactive oxygen species (ROS) production in human gastric AGS cells. Both extracts also showed antibacterial activity against different H. pylori strains. HPLC-PAD-MS characterization demonstrated that extract E1 was mainly composed of highly hydrophilic compounds, such as hydroxytyrosol (HT) and its glucosides, and it was the most effective extract as an antibacterial agent. In contrast, extract E2 was composed mostly of moderately hydrophilic compounds, such as oleuropein (OLE), and it was more effective than extract E1 as an anti-inflammatory agent. Both extracts exhibited similar potential to decrease ROS production. These results show the importance of standardizing the extract composition according to the bioactive properties that should be potentiated.<\/jats:p>","DOI":"10.3390\/antiox10122030","type":"journal-article","created":{"date-parts":[[2021,12,21]],"date-time":"2021-12-21T04:23:47Z","timestamp":1640060627000},"page":"2030","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Olive-Leaf Extracts Modulate Inflammation and Oxidative Stress Associated with Human H. pylori Infection"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8266-3761","authenticated-orcid":false,"given":"Jose Manuel","family":"Silvan","sequence":"first","affiliation":[{"name":"Microbiology and Food Biocatalysis Group (MICROBIO), Department of Biotechnology and Food Microbiology, Institute of Food Science Research (CIAL, CSIC-UAM), Cantoblanco Campus, Autonomous University of Madrid, C\/Nicol\u00e1s Cabrera 9, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esperanza","family":"Guerrero-Hurtado","sequence":"additional","affiliation":[{"name":"Department of Production and Characterization of Novel Foods, Institute of Food Science Research (CIAL, CEI, CSIC-UAM), Cantoblanco Campus, Autonomous University of Madrid, C\/Nicol\u00e1s Cabrera 9, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9643-1742","authenticated-orcid":false,"given":"Alba","family":"Guti\u00e9rrez-Docio","sequence":"additional","affiliation":[{"name":"Department of Production and Characterization of Novel Foods, Institute of Food Science Research (CIAL, CEI, CSIC-UAM), Cantoblanco Campus, Autonomous University of Madrid, C\/Nicol\u00e1s Cabrera 9, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9713-2952","authenticated-orcid":false,"given":"Teresa","family":"Alarc\u00f3n-Cavero","sequence":"additional","affiliation":[{"name":"Microbiology Department, Hospital Universitario de La Princesa, 28006 Madrid, Spain"},{"name":"Department of Preventive Medicine, Public Health and Microbiology, School of Medicine, Autonomous University of Madrid, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2059-9415","authenticated-orcid":false,"given":"Marin","family":"Prodanov","sequence":"additional","affiliation":[{"name":"Department of Production and Characterization of Novel Foods, Institute of Food Science Research (CIAL, CEI, CSIC-UAM), Cantoblanco Campus, Autonomous University of Madrid, C\/Nicol\u00e1s Cabrera 9, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6140-0732","authenticated-orcid":false,"given":"Adolfo J.","family":"Martinez-Rodriguez","sequence":"additional","affiliation":[{"name":"Microbiology and Food Biocatalysis Group (MICROBIO), Department of Biotechnology and Food Microbiology, Institute of Food Science Research (CIAL, CSIC-UAM), Cantoblanco Campus, Autonomous University of Madrid, C\/Nicol\u00e1s Cabrera 9, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"109683","DOI":"10.1016\/j.foodres.2020.109683","article-title":"Valorization of by-products from olive oil industry and added-value applications for innovative functional foods","volume":"137","author":"Astray","year":"2020","journal-title":"Food Res. 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