Figure 5
DHA activates PPARγ. (A) CD11c+ DC (5 × 106) were pretreated with increasing concentrations of DHA for 24 h, followed by 0.1 μg/ml LPS stimulation for 16 h. Activation of nuclear PPARγ was evaluated through binding to oligonucleotides containing PPRE as described in Methods. (B) DC were pretreated with the PPARγ inhibitor GW9662 (10 μM) for 2 h, followed by 50 μM DHA or 1 μM of the specific PPARγ agonist Rosiglitazone (Rosi) for 24 h, and LPS (0.1 μg/ml) for an additional 16 h. Activation of PPARγ was determined as described in (A). (C) CD11c+ DC (1 × 106/ml) were pretreated with 4 μM GW9662 for 2 h before the addition of 5 μM DHA or 0.4 μM Rosi (for 24 h) and LPS for an additional 24 h. Supernatants were collected and IL-12p70 production was determined by ELISA.