L-Carnitine reduces the adverse effects of ROS and up-regulates the expression of implantation related genes in in vitro developed mouse embryos

Background: In vitro developed embryos are inevitably exposed to various reactive oxygen species (ROS) which may decrease the embryos competence for ART purpose. Optimization of embryo culture media using antioxidant agents could help to improve the embryo quality and could overcome the mentioned issue.Objective: The aim of this study was to evaluate the effects of L-carnitine (LC) in culture media on early embryo competence and expression of ErbB1 and ErbB4 implantation related genes.Materials and Methods: Two-cell mouse embryos were cultured in four following conditions: LC group which transferred into a media containing L-carnitine; H2O2 group which exposed to H2O2 for 30 min and then transferred into a simple media; H2O2+LC group which exposed to H2O2 for 30 min and then transferred into a media containing L-carnitine; the simple group which only kept throughout in simple media. All groups were allowed to develop until the blastocyst stage. Then the ErbB1 and ErbB4 expression were evaluated by Real-time PCR and immunocytochemistry. The expression of Sirt3 gene was also evaluated. Moreover, intracellular ROS level was examined by DCFH-DA fluorescence intensity. In order to assess the morphological quality of the embryos, ICM and OCM number blastocyst cells were evaluated by using Hoechst and propidium iodide (PI) staining. The ErbB1, ErbB4, ROS levels and the number of cells were also compared with an in vivo developed blastocysts model.Results: Our data revealed that L-carnitine significantly increases the ErbB1 and ErbB4 gene and protein expression as implantation related genes. But, intracellular ROS level and consequently Sirt3 gene expression were significantly decreased after L-carnitine treatment. It is worth noting that an elevated cell number was observed in the LC-treated group compared with the other groups.Conclusion: Our findings suggest that the use of L-carnitine could be a helpful factor to improve the preimplantation embryo culture media through the decrease of ROS level and the increase of implantation-related genes.

کلیدواژه ها:

L-carnitine ، Embryonic Implantation genes ، Gene expression ، ROS