Figure 1.

GLUT4 and adiponectin expression are glucose-dependent. A, schematic of the three major phases of 3T3-L1 adipocyte cell culture. B, 3T3-L1 adipocytes grown under standard medium conditions and harvested every day post-differentiation induction with dexamethasone, isobutylmethylxanthine, and insulin (DII). C, 3T3-L1 adipocytes cultured in either 4 mm glucose-containing (L) or 25 mm glucose-containing (H) medium during the different phases of adipocyte cell culture as indicated. D, preadipocytes isolated from the stromal vascular fraction of mouse subcutaneous adipose tissue were induced for differentiation and pulsed with varying concentrations of glucose. E, 3T3-L1 adipocytes were induced for differentiation and pulsed with 25 mm glucose (Hi), 4 mm glucose (Lo), 50 μm palmitic acid and 4 mm glucose (PA) or 50 μm oleic acid and 4 mm glucose (OA) and cultured in Lo glucose medium during the P and M phases of their cell culture. Protein from whole-cell lysates of day 9 adipocytes were separated via SDS-PAGE and immunoblotted for GLUT4, adiponectin, and tubulin. Data shown are representative of n = 3 independent experiments