Ursodeoxycholic acid (UDCA) is used to treat liver diseases and demonstrates cardioprotective effects. Accumulation of the plasma membrane sphingolipid sphingomyelin in the heart can lead to atherosclerosis and coronary artery disease. Sphingomyelinases (SMases) break down sphingomyelin, producing ceramide, and inhibition of SMases activity can promote cell survival. We hypothesized that UDCA regulates activation of ERK and Akt survival signaling pathways and SMases in protecting cardiac cells against hypoxia.
Hepatocyte growth factor (HGF) is a protective factor in myocardial injury, but its mechanisms of action have not yet been fully elucidated. Nexilin, which locates specifically to the Z-disc, is a novel Z-disc protein that enables the Z-discs to persistently withstand the extreme mechanical forces generated during muscle contraction. Therefore, we investigated the role of HGF in modulating nexilin expression in hypoxia-reoxygenation (H/R)-treated cardiomyocytes. We cultured neonatal cardiomyocytes and treated them with HGF.