An Olive-Derived Extract 20% Rich in Hydroxytyrosol Prevents β-Amyloid Aggregation and Oxidative Stress, Two Features of Alzheimer Disease, via SKN-1/NRF2 and HSP-16.2 in <i>Caenorhabditis elegans</i>
Jose M. Romero-Márquez,
María D. Navarro-Hortal,
Victoria Jiménez-Trigo,
Pedro Muñoz-Ollero,
Tamara Y. Forbes-Hernández,
Adelaida Esteban-Muñoz,
Francesca Giampieri,
Irene Delgado Noya,
Pedro Bullón,
Laura Vera-Ramírez,
Maurizio Battino,
Cristina Sánchez-González,
José L. Quiles
Affiliations
Jose M. Romero-Márquez
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
María D. Navarro-Hortal
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Victoria Jiménez-Trigo
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Pedro Muñoz-Ollero
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Tamara Y. Forbes-Hernández
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Adelaida Esteban-Muñoz
Department of Nutrition and Bromatology, University of Granada, 18071 Armilla, Spain
Francesca Giampieri
Department of Clinical Sciences, Polytechnic University of Marche, 60131 Ancona, Italy
Irene Delgado Noya
Research Group on Foods, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres, 21, 39011 Santander, Spain
Pedro Bullón
Department of Periodontology, Dental School, University of Seville, C/Avicena, s/n, 41009 Seville, Spain
Laura Vera-Ramírez
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Maurizio Battino
Department of Clinical Sciences, Polytechnic University of Marche, 60131 Ancona, Italy
Cristina Sánchez-González
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
José L. Quiles
Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18100 Armilla, Spain
Olive milling produces olive oil and different by-products, all of them very rich in different bioactive compounds like the phenolic alcohol hydroxytyrosol. The aim of the present study was to investigate the effects of an olive fruit extract 20% rich in hydroxytyrosol on the molecular mechanisms associated with Alzheimer disease features like Aβ- and tau- induced toxicity, as well as on oxidative stress in Caenorhabditis elegans. Moreover, characterization of the extracts, regarding the profile and content of phenolics, as well as total antioxidant ability, was investigated. The study of lethality, growth, pharyngeal pumping, and longevity in vivo demonstrated the lack of toxicity of the extract. One hundred μg/mL of extract treatment revealed prevention of oxidative stress and a delay in Aβ-induced paralysis related with a lower presence of Aβ aggregates. Indeed, the extract showed the ability to avoid a certain degree of proteotoxicity associated with aggregation of the tau protein. According to RNAi tests, SKN-1/NRF2 transcription factor and the overexpression of HSP-16.2 were mechanistically associated in the observed effects.
