Adherence to Mediterranean diet is associated with methylation changes in inflammation-related genes in peripheral blood cells
JOURNAL OF PHYSIOLOGY AND BIOCHEMISTRY
Authors: Arpon, A.; Riezu-Boj, J. I.; Milagro, F. I.; Marti, A.; Razquin, C.; Martinez-Gonzalez, M. A.; Corella, D.; Estruch, R.; Casas, R.; Fito, M.; Ros, E.; Salas-Salvado, J.; Martinez, J. A.
Abstract
Epigenetic processes, including DNA methylation, might be modulated by environmental factors such as the diet, which in turn have been associated with the onset of several diseases such as obesity or cardiovascular events. Meanwhile, Mediterranean diet (MedDiet) has demonstrated favourable effects on cardiovascular risk, blood pressure, inflammation and other complications related to excessive adiposity. Some of these effects could be mediated by epigenetic modifications. Therefore, the objective of this study was to investigate whether the adherence to MedDiet is associated with changes in the methylation status from peripheral blood cells. A subset of 36 individuals was selected within the Prevencion con Dieta Mediterranea (PREDIMED)-Navarra study, a randomised, controlled, parallel trial with three groups of intervention in high cardiovascular risk volunteers, two with a MedDiet and one low-fat control group. Changes in methylation between baseline and 5 years were studied. DNA methylation arrays were analysed by several robust statistical tests and functional classifications. Eight genes related to inflammation and immunocompetence (EEF2, COL18A1, IL4I1, LEPR, PLAGL1, IFRD1, MAPKAPK2, PPARGC1B) were finally selected as changes in their methylation levels correlated with adherence to MedDiet and because they presented sensitivity related to a high variability in methylation changes. Additionally, EEF2 methylation levels positively correlated with concentrations of TNF-alpha and CRP. This report is apparently the first showing that adherence to MedDiet is associated with the methylation of the reported genes related to inflammation with a potential regulatory impact.
RIP3 antagonizes a TSC2-mediated pro-survival pathway in glioblastoma cell death
BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH
Authors: Fettweis, Gregory; Di Valentin, Emmanuel; L'homme, Laurent; Lassence, Cedric; Dequiedt, Franck; Fillet, Marianne; Coupienne, Isabelle; Piette, Jacques
Abstract
Glioblastomas are the deadliest type of brain cancer and are frequently associated with poor prognosis and a high degree of recurrence despite removal by surgical resection and treatment by chemo- and radio-therapy. Photodynamic therapy (PDT) is a treatment well known to induce mainly necrotic and apoptotic cell death in solid tumors. 5-Aminolevulinic acid (5-ALA)-based PDT was recently shown to sensitize human glioblastoma cells (LN-18) to a RIP3 (Receptor Interacting Protein 3)-dependent cell death which is counter-acted by activation of autophagy. These promising results led us to investigate the pathways involved in cell death and survival mechanisms occurring in glioblastoma following PDT. In the present study, we describe a new TSC2 (Tuberous Sclerosis 2) -dependent survival pathway implicating MK2 (MAPKAPK2) kinase and 14-3-3 proteins which conducts to the activation of a pro-survival autophagy. Moreover, we characterized a new RIP3/TSC2 complex where RIP3 is suggested to promote cell death by targeting TSC2-dependent survival pathway. These results highlight (i) a new role of TSC2 to protect glioblastoma against PDT-induced cell death and (ii) TSC2 and 14-3-3 as new RIP3 partners. (C) 2016 Published by Elsevier B.V.