Primary Adipocytes as a Model for Insulin Sensitivity

Obesity and its comorbidity insulin resistance lead to the development of chronic metabolic diseases, such as impaired fasted blood glucose and type 2 diabetes. Adipose tissue plays an important role in whole-body glucose homeostasis, particularly in obese individuals; therefore, many in vivo models of type 2 diabetes are obese, such as Lep^ob/ob and Lepr^db/db mice or ZDF rats. Primary adipocytes therefore represent an attractive in vitro model to study insulin-mediated glucose uptake to investigate the mechanisms of insulin resistance and explore the potential insulin-sensitizing properties of new antidiabetic drugs.Primary adipocytes are isolated by collagenase digestion of adipose tissue, Glucose transport is evaluated by the measurement of intracellular uptake of a tracer (D-[U¹⁴C] glucose). The uptake of [U-¹⁴ C] glucose reflects directly glucose transport.In this chapter, we will describe the protocol for the isolation of primary rodent adipocytes and the measurement of basal and insulin-stimulated glucose uptake.