The role of sphingomyelin cycle products in development of apoptosis induced through receptors of Fas and tumor necrosis factor α

Programmed cell death or apoptosis is a cell suicide developing according to a specific program, in which the sphingomyelin cycle products, ceramide and sphingosine, play the central role. The present review provides published data and the authors' results suggesting that the content of ceramide and sphingosine in the cell is controlled by the tumor necrosis factor alpha and activators of Fas receptor. The results of many experiments confirmed that the sphingomyelin cycle products induce cells death by the apoptotic pathway and enhance induced apoptosis. Ceramide and sphingosine regulate the activity of enzymes involved in transduction of apoptosis signal !protein kinases. Phosphatases, and proteases) and act as second messengers in transduction of the apoptosis signal.