Fig. 5

Induction of LIF, HBEGF, and IL11, as well as suppression of CXCL10, BAFF, MX1 and OAS2 is mediated via membrane receptors and not via direct intracellular signaling of S1P. Human U373 astrocytoma cells were treated with S1P (1 μM; can cross the cell membrane) or DH-S1P (1 μM; cannot cross the cell membrane) and 1 h later with TNF (0.025 μg/ml). Eight hours later, expression of a LIF, HBEGF, IL11, b CXCL10, BAFF, MX1, and OAS2 was determined by qPCR (values normalized to PPIA and the untreated control samples; mean ± SEM of five independent biological replicates; one-sample two-tailed t test for comparison with the unstimulated cells (normalized to a value of 1), two-sample two-tailed paired t test for comparison between other groups). Both S1P and the non-membrane-permeable derivate DH-S1P resulted in the induction of neurotrophic factors and suppression of inflammatory genes