Expression profile of Tbx20 and other cell cycle regulator genes at different proliferate stages of neonatal rat cardiomyocyte cultures and post-natal rat myocardium

BAUZÁ, MARÍA DEL ROSARIO; GIMÉNEZ, CARLOS SEBASTIÁN; SIMONIN ALEJANDRO; CASTILLO MARTHA GIOVANNA; LÓPEZ AYELÉN EMILCE; LOCATELLI, PAOLA; CUNIBERTI LUIS; BELAICH MARIANO NICOLÁS; CROTTOGINI ALBERTO; OLEA FERNANDA DANIELA

Mar del Plata

Congreso; Reunión Anual de la Sociedad Argentina de Fisiología; 2018

SAIC y SAFIS

Background and objectives: To induce cardiac regeneration with preservation of the physiologic electro-mechanical connection between contractile cells, the best approach would be to induce the adult cardiomyocyte to re-enter the cell cycle and divide into daughter cells. This requires disclosing positive and negative cell cycle regulator molecules that could be targeted to induce cardiomyocyte mitosis and eventually cytokinesis. In this regard, it has been recently reported that transgenic mice overexpressing Tbx20 displayed cardiomyocyte proliferation. We thus aimed at analyzing the expression of Tbx20 and other cell cycle regulatory genes at different proliferative stages of neonatal cardiomyocyte cultures and rat myocardium. Methods: Using the MTS assay, we first assessed cell proliferation in 2, 5 and 9 days old cultures of neonatal rat cardiomyocytes. Gene expression of the cell cycle stimulator genes Tbx20, Cyclin D1 and repressor genes p21 and p27 was evaluated (RT-qPCR) in 2, 5 and 9 days post-natal cardiomyocytes and in the myocardium of days 2, 5 and 9 post-natal rats and adults. Results: cardiomyocyte proliferation was maximal at day 5 of culture (3.87±0.14 area under the curve) vs day 2 (1.56±0.02AUC) and day 9 (1.59±0.1, p