Lack of a lipoprotein-induced insulin resistance in hepatoma cells in culture

Publisher Website
Google Scholar
Abstract
A lipoprotein-induced resistance to the action of insulin has been postulated. To test this hypothesis, cultured ratderived hepatoma cells, designated FAO, and human-derived hepatoma cells, designated HEP-G2, were incubated for 20 h in the presence or absence of lipoproteins; specific 125I-insulin receptor binding and labeled glucose incorporation into glycogen were then measured. Very low density lipoproteins (d < 1.006 g/ml) in physiologic (0.5 mg/ml) or pathophysiologic (5 mg/ml) concentrations did not modify insulin receptor binding of FAO or HEP-G2 cells. This was true for very low density lipoproteins derived from normal human, diabetic human, and streptozotocin-diabetic rat plasma. Low density lipoproteins (d=,.019–1.063g/ml) isolated from normal human plasma similarly failed to modify insulin receptor binding. Concerning insulin action, the different very low density lipoprotein preparations did not modulate either basal or insulin-stimulated glucose incorporation into glycogen of the cells. Thus, very low density lipoproteins and low density lipoproteins did not induce insulin resistance in cultured hepatoma cells either at the insulin receptor level or at the post-receptor level.