The contribution of splanchnic fat to VLDL triglyceride is greater in insulin-resistant than insulin-sensitive men and women: studies in the postprandial state.
The aim of this study was to determine differences in the postprandial contributions of different fatty acid sources to VLDL triglycerides in healthy men and women with/without insulin resistance. Men with insulin resistance were matched with insulin-sensitive men (n=11) on the basis of age, body mass index, waist circumference, and body fat. In women, 6 insulin-resistant women were matched with insulin-sensitive men on the basis of age, body mass index, and waist circumference. Insulin-resistant and insulin-sensitive men had similar postprandial chylomicron and chylomicron remnant triglyceride concentrations, but insulin-resistant men had higher postprandial VLDL triglyceride concentrations. At 6 hours, most of the difference in VLDL triglycerides was due to an additional contribution from splanchnic fat. The contribution of fatty acids from endogenous system non-esterified fatty acids was similar across the groups as were dietary fatty acids. There was also no difference in VLDL triglyceride concentrations nor in the contribution of different fatty acid sources between insulin-sensitive men and women. Therefore, in the postprandial state, the only sources of fatty acids for VLDL triglyceride production to differ between insulin-sensitive and insulin-resistant men are those derived from splanchnic sources.