title: HOX-1 and COX-2: Two differentially regulated key mediators of skeletal myoblast tolerance under oxidative stress.
abstract: The exact physiological role of oxidative stress as a primary cause for skeletal muscle pathological conditions involving muscle degeneration remains elusive. Therefore, the present study was performed so as to decipher the signalling pathways orchestrating the potential cytoprotective role of heme oxygenase 1 (HOX-1) as well as cyclooxygenase 2 (COX-2) in skeletal myoblasts exposed to H(2)O(2). Cell treatment with H(2)O(2) (0.5 mM) resulted in a time- and dose-dependent response of HOX-1 and COX-2 mRNA and protein levels, with ERK1/2, p38-MAPK and MSK1 found to mediate these effects. Furthermore, Src and JNKs blockade attenuated COX-2 response. Collectively, these novel findings highlight for the first time HOX-1 and COX-2 fundamental contribution to skeletal myoblast tolerance under oxidative stress, since their inhibition significantly attenuated viability of skeletal myoblasts. The data also delineate the various effectors regulating HOX-1 and COX-2 expression, probably alleviating muscle degeneration in related disorders.
authors.affiliation: Department of Animal and Human Physiology, School of Biology, Faculty of Sciences, University of Athens, Panepistimioupolis, Ilissia, Athens 157 84, Greece.
authors.forename: Ioanna-Katerina
authors.initials: IK
authors.lastname: Aggeli
authors.forename: Eirini
authors.initials: E
authors.lastname: Kefaloyianni
authors.forename: Isidoros
authors.initials: I
authors.lastname: Beis
authors.forename: Catherine
authors.initials: C
authors.lastname: Gaitanaki
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D051547:Heme Oxygenase-1 / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D051379:Mice; D032448:Myoblasts, Skeletal / Q000187:drug effects / Q000378:metabolism*; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
chemical_list: D016877:Oxidants; D012333:RNA, Messenger; D006861:Hydrogen Peroxide; D051547:Heme Oxygenase-1; D051546:Cyclooxygenase 2