Figure 5.

Leptin induces expression of IL-1α gene. (A) leptin transcriptional activation of IL-1α reporter, (B) effects of siRNA for SP1 and NF-κB. 4T1 cells were transiently transfected with a IL-1α reporter construct and treated with leptin (0 and 1.2 nM) and siRNA-SP1 and shRNA–NF-κB for 24 h. Luciferase activity was determined as described (see Materials and Methods) and expressed as a percent of basal or leptin-treated cells. (a) and (b) P<0.05 when comparing levels of luciferase activity to control (basal) or leptin-treated cells, respectively. Data (mean±s.e.) are representative of the results derived from a minimum of three independent experiments.