Role of sphingosine 1-phosphate in anti-atherogenic actions of high-density lipoprotein

The reverse cholesterol transport mediated by highdensity lipoprotein(HDL)is an important mechanism for maintaining body cholesterol,and hence,the crucial anti-atherogenic action of the lipoprotein.Recent studies,however,have shown that HDL exerts a variety of anti-inflammatory and anti-atherogenic actions independently of cholesterol metabolism.The present review provides an overview of the roles of sphingosine 1-phosphate(S1P)/S1P receptor and apolipoprotein A-I/ scavenger receptor class B typeⅠsystems in the antiatherogenic HDL actions.In addition,the physiological significance of the existence of S1P in the HDL particles is discussed.