Synergism between cAMP and PPAR Signalling in the Initiation of UCP1 Gene Expression in HIB1B Brown Adipocytes
The effect of forskolin and rosiglitazone on mRNA expression of (a) UCP1, (b) PGC1, (c) Cidea, (d) PRDM16, (e) C/EBP, and (f) PPAR is mediated by PKA and PPAR dependent pathways. HIB-1B cells were grown to confluence and then treated with H89 (10 M) for 1 hour or GW9662 (30 M) for 3 hours prior to and during addition of rosiglitazone (Rosi) (10 M) for 24 hours, or forskolin (Fosk) (10 M) for the final 3 hours of rosiglitazone treatment, before RNA extraction, as indicated. All drugs were added in serum-free medium. Controls were treated with DMSO. Gene expression levels were analysed by quantitative real-time PCR and normalized against 36B4 expression. Error bar means the mean SEM of triplicate observations within a single experiment performed in triplicate. *** Significant difference with respect to control; ### significant difference due to H89 or GW9662 for each experiment.