Fig. 1
S1P3 is highly expressed in astrocytes and mediates COX-2 expression. In WT astrocytes, a S1P1, S1P2, and S1P3 mRNA expression was measured by absolute PCR. b Quantification and Western blot of COX-2 protein expression after S1P treatment (0.5 μM, 6 h) following knockdown of S1P1, S1P2, S1P3, and S1P2/3 with siRNA (2 μM). Data shown are mean ± SEM of values from three independent experiments run in triplicate. COX-2 was normalized to GAPDH and expressed relative to control siRNA vehicle treated. *p < 0.05 and **p < 0.01 between vehicle and S1P-treated groups and #p < 0.05 and ##p < 0.01 between control siRNA S1P-treated and S1P receptor siRNA S1P-treated groups. c Quantification and Western blot of COX-2 expression after pretreatment with the S1P2 antagonist JTE-013 for 30 min (1 μM) followed by S1P treatment (0.5 μM, 6 h). Data shown are mean ± SEM of values from three independent samples. COX-2 was normalized to GAPDH and expressed relative to vehicle control. *p < 0.05 between vehicle and S1P-treated groups. d Quantification and Western blot of COX-2 expression after pretreatment with the S1P3 antagonist SPM-354 for 15 min (5 μM) followed by S1P treatment (0.5 μM, 6 h). Data shown are mean ± SEM of values from three independent experiments run in triplicate. COX-2 was normalized to GAPDH and expressed relative to vehicle control. *p < 0.05 between vehicle and S1P-treated groups and #p < 0.05 between control S1P-treated and SPM-454/S1P-treated group