Figure 8From: Ceramide sphingolipid signaling mediates Tumor Necrosis Factor (TNF)-dependent toxicity via caspase signaling in dopaminergic neuronsTNF treatment induces accumulation of ceramide and several atypical sphingoid bases (DBS) in MN9D dopaminergic (DA) neuroblastoma cells derived from mouse ventral mesencephalon. MN9D cells were treated with PBS or 5 ng/mL TNF for 24 or 48 hours as indicated prior to cell harvest for lipid extraction as described in Methods. A, Lipidomic analyses indicate time-dependent accumulation of ceramide (Cer), sphingomyelin (SM), and hexosylceramide (HexCer) in TNF-treated cells relative to PBS-treated cells. B, Lipidomic analyses also revealed time-dependent accumulation of sphingosine (So), sphinganine (Sa), sphingosine-phosphate (SoP), sphinganine-phosphate (SaP), 1-deoxysphinganine (1-deoxySa), and 1-desoxymethylsphinganine (1-desoxyMeSa) after treatment with TNF. All values represent group means +/− SEM, n = 3. One-way ANOVA with Tukey’s post-hoc test; *** denotes p < 0.001 and * denotes p < 0.05 compared to PBS at 48 hrs. N.S. denotes not significant.Back to article page