Ceramide is a key bioactive mediator that inhibits surfactant phosphatidylcholine (PtdCho) synthesis in lung epithelia. Ceramide availability is governed by sphingomyelin (SM) hydrolysis, but less is known regarding its de novo synthesis. In this study, we observed that ceramide synthesis within murine lung epithelia was associated with high-level ceramide synthase (dihydroceramide synthase) ac...

We found that natural (long-chain) ceramide 1-phosphate can be dispersed into aqueous solution when dissolved in an appropriate mixture of methanol/dodecane (49:1, v/v). This solvent mixture facilitates the interaction of this phosphosphingolipid with cells. Under these conditions, incubation of EGFR T17 fibroblasts with natural ceramide 1-phosphate caused a potent stimulation of DNA synthesis....

BACKGROUND Ethanol inhibits proliferation in astrocytes, an effect that was recently linked to the suppression of phosphatidic acid (PA) formation by phospholipase D (PLD). The present study investigates ethanol's effect on the induction of apoptosis in astrocytes and the formation of ceramide, an apoptotic signal. Evidence is presented that the formation of PA and ceramide may be reciprocally ...

Ceramides are the metabolic products of sphingolipids of the eukaryotic cell membranes and are believed to function as signaling molecules in a variety of biological processes. Ceramide induces apoptosis in cultured cardiomyocytes. However, the molecular pathway underlying ceramide-induced apoptosis is not clear. In this study, we investigated the role of the cysteinyl aspartate-specific protea...

Recent studies indicate that distinct membrane microdomains, also named lipid rafts, and ceramide play an important role in infectious biology. Ceramide forms larger ceramide-enriched membrane platforms that are required for diverse signal transduction. In this study, we demonstrate that ceramide-enriched membrane platforms are critically involved in redox signaling that regulates alveolar macr...

Studies of ceramide metabolism and function in a wide range of biological processes have revealed a role for this lipid in regulating key cellular responses. Our research on the role of sphingolipids in HIV entry has led to the hypothesis that modulation of ceramide levels in target cells affects their susceptibility to HIV infection by rearranging HIV receptors. Cellular ceramide levels were m...

Stress signals induce ceramide (cer) through sphingomyelinase activation, and metabolites of cer such as sphingosine (Sph) and sphingosine-1-phoshate (S-1-P) play a significant role in many biological processes. This study aimed to elucidate the association between the alteration in cell surface sialylation and ceramide-induced cell death in the human Burkitt's lymphoma cell line, HBL-8. The hi...

The tumour suppressor p53 induces cell death by launching several pathways that are either dependent on or independent of gene transcription. Accumulation of the sphingolipid ceramide and reactive oxygen species are among these pathways. Crossregulation of these two pathways is possible owing to the demonstrated inhibition of neutral sphingomyelinase by glutathione, the predominant cellular ant...

Uncorrected obesity is often accompanied by ventricular contractile dysfunction, elevation of the lipotoxic mediator ceramide and the obesity gene product leptin. Both ceramide and leptin participate in the regulation of cardiac function and are speculated to play roles in obesity-related cardiac dysfunctions. The purpose of this study was to examine the effect of ceramide on leptin-elicited ca...

Brief "preconditioning" ischemia induces ischemic tolerance (IT) and protects the animal brain from subsequent otherwise lethal ischemia. Identification of the signaling steps most proximal to the development of the IT will allow induction of the resistance to ischemia shortly after the onset of stroke. Animal studies demonstrate a key role of tumor necrosis factor-alpha (TNF-alpha) in inductio...