Insulin stimulated glucose uptake

 

One of the hallmarks of type II diabetes is decreased sensitivity of muscle and adipose cells to insulin. Compounds that increase the sensitivity of adipose to insulin may be useful in the treatment of diabetes and its complications.

Treatment with insulin induces phosphorylation of the insulin receptor and activation of a signal transduction pathway. This leads to the translocation of the glucose transporter 4 (GLUT4) to the cell membrane and enhances glucose uptake in adipocytes (fat) and myocytes (muscle). Therefore, measuring glucose uptake provides a relevant end point assay for insulin sensitivity. Our assay uses [3H]-2-deoxyglucose as the substrate for Glut4. The assay is conducted in a 96-well format for higher throughput. Our standard assay controls include insulin (100 nM) as a positive control and Cytochalasin B (10μM) as a negative control.

 

Figure 1 shows representative results for insulin-stimulated glucose uptake. Data is calculated as mean counts per well. The assay was performed using subcutaneous human adipocytes at two weeks post-differentiation. The calculated EC50 for insulin is 1nM.