The Effect of Altered Sphingolipid Acyl Chain Length on Various Disease Models

Sphingolipids have emerged as an important lipid mediator in intracellular signalling and metabolism. Ceramide, which is central to sphingolipid metabolism, is generated either via a de novo pathway, by attaching fatty acyl CoA to a long-chain base, or via a salvage pathway, by degrading pre-existing sphingolipids. As a 'sphingolipid rheostat' has been proposed, the balance between ceramide and sphingosine-1-phosphate has been the object of considerable attention. Ceramide has recently been reported to have a different function depending on its acyl chain length: six ceramide synthases (CerS) determine the specific ceramide acyl chain length in mammals. All CerS-deficient mice generated to date show that sphingolipids with defined acyl chain lengths play distinct pathophysiological roles in disease models. This review describes recent advances in understanding the associations of CerS with various diseases and includes clinical case reports.