VLDL-triglyceride kinetics during hyperglycemia-hyperinsulinemia: effects of sex and obesity.

Abstract

We have previously shown that sex and obesity independently affect basal very low density lipoprotein (VLDL)-triglyceride (TG) kinetics. In the present study, we investigated the effect of hyperglycemia-hyperinsulinemia on VLDL-TG kinetics in lean and obese men and women (n = 6 in each group). VLDL-TG kinetics were measured during basal, postabsorptive conditions and during glucose infusion (5.5 mg x kg FFM(-1) x min(-1)) by using [(2)H(5)]glycerol bolus injection in conjunction with compartmental modeling analysis. Basal VLDL-TG secretion in plasma was greater in obese than in lean men (7.8 +/- 0.6 and 2.9 +/- 0.4 micromol x l plasma(-1) x min(-1); P < 0.001) but was not different in lean and obese women (5.0 +/- 1.1 and 5.9 +/- 1.1 micromol x l plasma(-1) x min(-1)). Glucose infusion decreased the VLDL-TG secretion rate by approximately 50% in lean and obese men and in lean women (to 1.5 +/- 0.4, 4.0 +/- 0.6, and 2.2 +/- 0.4 micromol x l plasma(-1) x min(-1), respectively; all P < 0.05) but had no effect on the VLDL-TG secretion rate in obese women (4.9 +/- 1.0 micromol x l plasma(-1) x min(-1)). These results demonstrate that both sex and adiposity affect the regulation of VLDL-TG metabolism. Glucose and insulin decrease VLDL-TG production in both lean men and lean women; obesity is associated with resistance to the glucose- and insulin-mediated suppression of VLDL-TG secretion in women, but not in men.

• Authors: Bettina Mittendorfer, Bruce W Patterson, Samuel Klein, Labros S Sidossis
• Journal: American journal of physiology. Endocrinology and metabolism (Am J Physiol Endocrinol Metab) Vol. 284 Issue 4 Pg. E708-15 (Apr 2003) ISSN: 0193-1849 [Print] United States
• PMID: 12475756 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Blood Glucose
• Cholesterol, VLDL
• Fatty Acids
• Insulin
• Triglycerides
• Glucose

Topics

• Adult
• Blood Glucose (metabolism)
• Cholesterol, VLDL (blood)
• Coronary Disease (metabolism)
• Fatty Acids (blood)
• Female
• Glucose (administration & dosage)
• Humans
• Hyperglycemia (metabolism)
• Hyperinsulinism (metabolism)
• Insulin (blood)
• Insulin Resistance
• Kinetics
• Male
• Obesity (metabolism)
• Sex Factors
• Triglycerides (blood)