Background: Although there are several reported evidences for a pathogenic role of sphingolipid signaling in atherosclerosis, peripheral blood levels of ceramide and secretory acid sphingomyelinase (S-SMase) activity in patients with acute coronary syndromes (ACS) have not been evaluated.
Methods and results: A total of 304 CAD patients and 52 healthy individuals were divided into four groups: control group (n=52), stable angina pectoris (SAP) group (n=98), unstable angina pectoris (UAP) group (n=92), and acute myocardial infarction (AMI) group (n=114). Plasma levels of sphingomyelin (SPM) were elevated in patients with UAP and AMI compared with those in the control and SAP participants. Plasma ceramide levels and S-SMase activity in patients with ACS (including UAP and AMI) on day 0 were significantly higher than those in the control and SAP participants. Elevation in plasma ceramide levels in patients with UAP and AMI was sustained until a day after percutaneous coronary intervention or day 7, respectively. Moreover, in patients with UAP, S-SMase activity elevation on day 0 was followed by a gradual decrease toward the SAP range up to a day after percutaneous coronary intervention. In patients with AMI, elevation in S-SMase activity showed a peak on day 3.
Conclusion: Serial changes in plasma ceramide and S-SMase activity were documented in patients with ACS. These findings provide an insight into the molecular mechanism of plaque destabilization.