Leptin Antagonizes Peroxisome Proliferator-Activated Receptor-γ Signaling in Growth Plate Chondrocytes
Figure 2
Leptin inhibits PPAR signaling in growth plate chondrocytes by enhancing PPAR phosphorylation via MAPK/ERK pathway. (a) PPAR-mediated PPRE transcriptional activity in chondrocytes treated with leptin at a concentration ranged from 0.1 to 1 μg/mL. * versus the samples untreated with leptin. (b) PPAR mRNA expression of growth plate chondrocytes in response to leptin treatment. (c) Immunoblotting analysis of the levels of total and phosphorylated (Ser112/82) PPAR protein in chondrocytes treated with leptin for 2 h. For ERK or JNK inhibition experiments, the cells were preincubated with PD98059 or SP600125 for 30 min before leptin treatment. (d) Expression of total and phosphorylated ERK proteins (ERK1/2) in growth plate chondrocytes treated with leptin for 1 h and 2 h.
