![]() ; ; et al in Frontiers in physiology (2013), 4 Background: Ventricular tachyarrhythmias are the most common and often the first manifestation of coronary heart disease and lead to sudden cardiac death (SCD). Early detection/identification of acute ... [more ▼] Background: Ventricular tachyarrhythmias are the most common and often the first manifestation of coronary heart disease and lead to sudden cardiac death (SCD). Early detection/identification of acute myocardial ischaemic injury at risk for malignant ventricular arrhythmias in patients remains an unmet medical need. In the present study, we examined the sphingolipids level after transient cardiac ischaemia following temporary coronary artery occlusion during percutaneous coronary intervention (PCI) in patients and determined the role of sphingolipids level as a novel marker for early detection of human myocardial ischaemic injury. Methods and Results: Venous samples were collected from either the coronary sinus (n = 7) or femoral vein (n = 24) from 31 patients aged 40-73 years-old at 1, 5 min, and 12 h, following elective PCI. Plasma sphingolipids levels were assessed by HPLC. At 1 min coronary sinus levels of sphingosine 1-phosphate (S1P), sphingosine (SPH), and sphinganine (SA) were increased by 314, 115, and 614%, respectively (n = 7), while peripheral blood levels increased by 79, 68, and 272% (n = 24). By 5 min, coronary sinus S1P and SPH levels increased further (720%, 117%), as did peripheral levels of S1P alone (792%). Where troponin T was detectable at 12 h (10 of 31), a strong correlation was found with peak S1P (R (2) = 0.818; P < 0.0001). Conclusion: For the first time, we demonstrate the behavior of plasma sphingolipids following transient cardiac ischaemia in humans. The observation supports the important role of sphingolipids level as a potential novel marker of transient or prolonged myocardial ischaemia. [less ▲] Detailed reference viewed: 171 (1 UL)![]() ; ; Neyses, Ludwig ![]() in Critical reviews in clinical laboratory sciences (2013), 50(3), 79-89 The mechanisms by which statins are beneficial are incompletely understood. While the lowering of low-density lipoprotein concentration is associated with regression of atherosclerosis, the observed ... [more ▼] The mechanisms by which statins are beneficial are incompletely understood. While the lowering of low-density lipoprotein concentration is associated with regression of atherosclerosis, the observed benefit of statin therapy begins within months after its initiation, making regression an unlikely cause. Although LDL-C lowering is the main mechanism by which statin therapy reduces cardiovascular events, evidence suggests that at least some of the beneficial actions of statins may be mediated by their pleiotropic effects. Thus, statins may modulate the function of cardiovascular cells and key signalling proteins, including small G-proteins, to ultimately exert their pleiotropic effects. Sphingosine-1-phosphate (S1P) is a naturally occurring bioactive lysophospholipid that regulates diverse physiological functions in a variety of different organ systems. Within the cardiovascular system, S1P mediates cardioprotection following ischemia/reperfusion injury, anti-inflammatory response, improvement of endothelial function, increased mobilization and differentiation of endothelial progenitor cells, inhibition of oxidation, and anti-atherogenic and anti-thrombotic actions. Early evidence suggests that the pleiotropic effects of statins may be related to an increase in S1P signalling. This review focuses on S1P signalling as the potential mechanism underlying the pleiotropic effects of statins. An improved understanding of this mechanism may be vital for establishing the clinical relevance of statins and their importance in the treatment and prevention of coronary artery disease. Key points Several studies have demonstrated a benefit from lowering serum LDL-C with statins in patients with and without clinical evidence of CAD. These may be mediated by the pleiotropic effects of statins-the mechanisms of which are incompletely understood. Early evidence suggests that statins may increase S1P signalling pathways through upregulation of the expression of S1P receptors and an increase in plasma levels of S1P to ultimately exert their pleiotropic effects. Future clinical trials and basic science research aimed at the underlying mechanisms of the pleiotropic effects of statins should enlighten us to their relative clinical relevance and importance. [less ▲] Detailed reference viewed: 130 (0 UL) |
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