Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain.
Lipids Health Dis. 2010 Feb 5;9:15. doi: 10.1186/1476-511X-9-15.
Sphingolipids are essential components of cell membranes, and many of them regulate vital cell functions. In particular, ceramide plays crucial roles in cell signaling processes. Two major actions of ceramides are the promotion of cell cycle arrest and the induction of apoptosis. Phosphorylation of ceramide produces ceramide 1-phosphate (C1P), which has opposite effects to ceramide. C1P is mitogenic and has prosurvival properties. In addition, C1P is an important mediator of inflammatory responses, an action that takes place through stimulation of cytosolic phospholipase A2, and the subsequent release of arachidonic acid and prostaglandin formation. All of the former actions are thought to be mediated by intracellularly generated C1P. However, the recent observation that C1P stimulates macrophage chemotaxis implicates specific plasma membrane receptors that are coupled to Gi proteins. Hence, it can be concluded that C1P has dual actions in cells, as it can act as an intracellular second messenger to promote cell survival, or as an extracellular receptor agonist to stimulate cell migration.
鞘脂是细胞膜的重要组成部分，其中许多调节重要的细胞功能。特别是，神经酰胺在细胞信号转导过程中起着关键作用。神经酰胺的两个主要作用是促进细胞周期停滞和诱导细胞凋亡。神经酰胺的磷酸化产生神经酰胺 1-磷酸（C1P），它与神经酰胺的作用相反。C1P 具有促有丝分裂作用和生存促进特性。此外，C1P 是炎症反应的重要介质，这种作用通过刺激细胞质磷脂酶 A2 发生，随后释放花生四烯酸和前列腺素形成。所有这些前一个作用被认为是由细胞内产生的 C1P 介导的。然而，最近的观察表明，C1P 刺激巨噬细胞趋化性暗示存在与 Gi 蛋白偶联的特定质膜受体。因此，可以得出结论，C1P 在细胞中有双重作用，因为它可以作为细胞内的第二信使促进细胞存活，或者作为细胞外受体激动剂刺激细胞迁移。
