Efeitos de agentes desmetilantes sobre a viabilidade celular e expressão gênica em fibroblastos bovinos cultivados in vitro

Abstract

During the process of cloning using nuclear transfer, epigenetic marks in cells must go through a reprogramming process, so that embryonic development can occur appropriately. However, during TN this reprogramming process is not completely efficient. Analysis of cell viability and expression of genes related to pluripotency and epigenetic changes, allowed us to evaluate the action of demethylation drugs such as Procaine and SAH in somatic cell cultures. These substances are potencial inducers of epigenetic reprogramming and they could be used to improve the process of cloning by TN. The bovine fibroblasts treated with 1 mM Procaine had lower cell viability compared to the control group (non trated), while the group treated with 2 mM of SAH did not differ from the controls. OCT4 and NANOG genes were detected in control group as well as in the group treated with 1mM Procaine, while HDAC2 and DNMT1 genes were expressed in cells treated with 1 mM of Procaine as in those treated with 2 mM of SAH, showing no significant difference between the experimental groups. In this study we concluded that the OCT4 and NANOG genes are not molecular markers for cellular pluripotency in bovines and we can modify the epigenetic patterns of DNA of the nucleus donor cells for cloning by TN process, contributing to the improving of the results of this technique.