Fig. 6

Serum PPARγ Activity can be detected in whole serum from rosiglitazone-treated mice in a dose-dependent manner. Sera were generated from nine-week-old, female, C57BL/6 J mice were treated by oral gavage with Vh (1% carboxymethylcellulose, 0.1% DMSO) or rosiglitazone (0.1, 1, 10, 100 mg/kg) and euthanized after 1 h. Sera were analyzed in Cos-7 cells transfected with reporter plasmids (PPRE-luciferase reporter, CMV-GFP reporter) and human PPARG1. Experimental wells were treated with 10 μL mouse serum, in duplicate. Luminescence and fluorescence were measured after 24 h. Data were calculated as described in the Methods and were calculated relative to the standard curve shown in Fig. 5. (a) Dose response of serum PPRE transcriptional activity. All mice were treated on the same day. (b) Reproducibility assessment. Mice were treated on three different days, with independently prepared dose solutions. Mice from each experiment are indicated by different symbols. For A and B, individual data are plotted with the mean indicated by a line. Different letters indicate group means that differed significantly, while groups with the same letter did not differ significantly (p < 0.05, ANOVA, Tukey). (c) To test for receptor specificity, wells treated with serum from mice that were exposed to Vh or to 1 mg/kg rosiglitazone were co-treated with Vh (0.5%, 50:50, DMSO:Ethanol), PPARγ antagonist (T0070907, 1 μM) or RXR antagonist (HX 531, 2 μM). For C, data are presented as means ± standard error from all mice in the treatment group. Significantly different from Vh (**p < 0.01, 2-Factor ANOVA, Sidak’s)