Roles of Protein Kinase C δ in the Accumulation of P53 and the Induction of Apoptosis in H 2 O 2 -treated Bovine Endothelial Cells

Abstract

To clarify the signaling pathways of oxidative stress-induced apoptosis in bovine aortic endothelial cells (BAEC), we treated cells with 1 mM H 2 O 2 and investigated the roles of protein kinase C &#105 (PKC &#105 ) and Ca 2+ in the accumulation of p53 associated with apoptosis. The treatment of cells with H 2 O 2 caused the accumulation of p53, which was inhibited by rottlerin (a PKC &#105 inhibitor) but not by BAPTA-AM (an intracellular Ca 2+ chelator). PKC &#105 itself was activated through the phosphorylation at tyrosine residues. H 2 O 2 induced the release of cytochrome c and the activation of caspases 3 and 9, and these apoptotic signals were inhibited by rottlerin and BAPTA-AM. These results suggest that PKC &#105 contributes to the accumulation of p53 and that Ca 2+ plays a role in downstream signals of p53 leading to apoptosis in H 2 O 2 -treated BAEC.

• Pkcδ
• Ca 2+
• P53
• H 2 O 2
• Apoptosis
• Endothelial Cells