title: PKC-δ signalling pathway is involved in H9c2 cells differentiation.
abstract: H9c2 are rat heart embryonic myoblasts, with skeletal muscle properties, which terminally differentiate by fusing and forming multinucleated myotubes. Here we investigated the possible involvement of Protein Kinases C (PKCs) in H9c2 cell differentiation and explored the interplay of these enzymes both with reactive oxygen species (ROS), upstream physiological mediators of cell differentiation, and with nitric oxide (NO), downstream target of PKC activation, known for being involved in apoptosis induction in differentiated myoblasts. Cells were induced to differentiate (6 days) under low serum culture conditions and assayed for the expression of cell cycle (cyclin A) and differentiation markers (morphology and myogenin). Both ROS and in vivo production of NO were found increased after 6 days of differentiation, when the activation of PKC-δ isoform was 14-fold increased compared with the undifferentiated control cells. The parallel analysis of apoptotic features demonstrated a small increase in Annexin-V+ cells and a concomitant increase in PARP cleavage and Bax expression. Interestingly, a reduced percentage of differentiated cells was obtained both in the presence of Rottlerin, a highly selective PKC-δ pharmacologic inhibitor, and, moreover, with the use of PKC-δ siRNA technology, further supporting the involvement of PKC-δ in switching on the events related to skeletal muscle myoblast differentiation.
authors.affiliation: Dipartimento di Medicina e Scienze dell'Invecchiamento, Chieti, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: di Giacomo
authors.forename: Monica
authors.initials: M
authors.lastname: Rapino
authors.forename: Silvia
authors.initials: S
authors.lastname: Sancilio
authors.forename: Antonia
authors.initials: A
authors.lastname: Patruno
authors.forename: Susi
authors.initials: S
authors.lastname: Zara
authors.forename: Roberta
authors.initials: R
authors.lastname: Di Pietro
authors.forename: Amelia
authors.initials: A
authors.lastname: Cataldi
mesh_terms: D000818:Animals; D017209:Apoptosis; D002453:Cell Cycle; D002454:Cell Differentiation; D002478:Cells, Cultured; D032446:Myoblasts / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D051745:Protein Kinase C-delta / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D009569:Nitric Oxide; D051745:Protein Kinase C-delta