Pre-IVM with C-type natriuretic peptide promotes mitochondrial biogenesis of bovine oocytes via activation of CREB.

The aim of this study was to evaluate the effects of C-type natriuretic peptide (CNP) treatment prior to in vitro maturation (IVM) on mitochondria biogenesis in bovine oocyte matured in vitro and explore the related causes. The results showed that treatment with CNP before IVM significantly improved mitochondrial content, elevated the expression of genes related to mitochondria biogenesis, and increased the protein levels of phosphorylation of cAMP-response element binding protein (p-CREB) in bovine oocytes following IVM. However, further studies revealed that treatment with CNP before IVM could not increased the protein levels of p-CREB in bovine oocytes when natriuretic peptide receptor 2 activities was inhibited using the relative specific inhibitor Gö6976. In addition, treatment with CNP before IVM could not improved mitochondrial content or elevated the expression of genes related to mitochondria biogenesis in bovine oocytes when CREB activities was abolished using the specific inhibitor 666-15. In summary, these results provide evidence that treatment of bovine oocytes with CNP before IVM promotes mitochondrial biogenesis in vitro, possibly by activating CREB.