Inflammation affects lipid metabolism during recovery from hyperinsulinaemia

Inflammation is an established contributor in atherosclerosis and several other common diseases including diabetes. Therefore the study was to investigate how inflammatory factors affect lipid metabolism during recovery from hyperinsulinaemia in healthy individuals.

A total of 22 healthy subjects [aged 27.7 +/- 1.8 years; body mass index (BMI) 24.1 +/- 0.8 kg m(-2)] participated in the study. After a 4-h euglycaemic hyperinsulinaemia (55.9 +/- 2.2 mU L(-1)) insulin infusion was stopped and baseline blood samples were taken. Glucose infusion at a decreasing rate continued for 120 min to maintain euglycaemia throughout the study.

The free fatty acid (FFA) concentration at the 120-min time-point was associated with baseline alpha-1-acid glycoprotein (A1GP) (r = 0.57, P < 0.01), C-reactive protein (CRP) (r = 0.54, P < 0.02) and serum amyloid A (r = 0.53, P < 0.02); in total they accounted for 54% of the variation in FFA concentration at the 120-min time-point. Baseline A1GP was also associated with the triglyceride concentration at the 120-min time-point (r = 0.66, P < 0.001). Insulin sensitivity was the most important factor associated with glucose disposal at the 120-min time-point, thus explaining 30% of the variation (P < 0.01). Interleukin-6 (positive correlation) and fibrinogen (negative correlation) increased the proportion to 48% (P < 0.01). There was no significant change in the most acute-phase proteins between baseline and the 120-min time-point.

Inflammation is an important contributor to lipid and glucose metabolism during recovery from hyperinsulinaemia.