Fig. 2.

Effect of N,N-dimethylsphingosine (DMS) and DL-threo-dihydrosphingosine (DHS), pharmacological SphK inhibitors, on adipogenesis. Confluent 3T3-L1 preadipocytes were treated with a hormonal stimulation to induce adipogenesis as above. DMS, DHS, or ethanol (vehicle) was also included throughout the treatment protocol using an adipogenic hormonal stimulation for 8 days, as described in detail under Materials and Methods. Cells were then subjected to Oil Red O staining followed by quantification using a spectrophotometer. The degree of Oil RedO staining in each treatment condition was normalized and expressed as a percentage of the values obtained in the absence of DMS/DHS in each culture. Closed (DMS) and open (DHS) circles represent means ± SEM of pooled data, derived from five independent experiments. * P < 0.05, ** P < 0.01 vs. values obtained with vehicle alone.