Postprandial leg uptake of triglyceride is greater in women than in men

Abstract

leg uptake of triglyceride is greater in women than in men. Am J Physiol Endocrinol Metab 283: E1192-E1202, 2002 10.1152/ajpendo.00164. 2002The postprandial excursion of plasma triglyceride (TG) concentration is greater in men than in women. In this study, the disposition of dietary fat was examined in lean healthy men and women (n ϭ 8/group) in either the overnight-fasted or fed (4.5 h after breakfast) states. A [ 14 C]oleate tracer was incorporated into a test meal, providing 30% of total daily energy requirements. After ingestion of the test meal, measures of arteriovenous differences in TG and 14 C across the leg were combined with needle biopsies of skeletal muscle and adipose tissue and respiratory gas collections to define the role of skeletal muscle in the clearance of dietary fat. The postprandial plasma TG and 14 C tracer excursions were lower (P ϭ 0.04) in women than in men in the overnight-fasted and fed states. Women, however, had significantly greater limb uptake of total TG compared with men on both the fasted (3,849 Ϯ 846 vs. 528 Ϯ 221 total mol over 6 h) and fed (4,847 Ϯ 979 vs. 1,571 Ϯ 334 total mol over 6 h) days. This was also true for meal-derived 14 C lipid uptake.14 C content of skeletal muscle tissue (Ci/g tissue) was significantly greater in women than in men 6 h after ingestion of the test meal. In contrast, 14 C content of adipose tissue was not significantly different between men and women at 6 h. The main effect of nutritional state, fed vs. fasted, was to increase the postmeal glucose (P ϭ 0.01) excursion (increase from baseline) and decrease the postmeal TG excursion (P ϭ 0.02). These results support the notion that enhanced skeletal muscle clearance of lipoprotein TG in women contributes to their reduced postprandial TG excursion. Questions remain as to the mechanisms causing these sex-based differences in skeletal muscle TG uptake and metabolism. Furthermore, nutritional state can significantly impact postprandial metabolism in both men and women. dietary fat; gender; skeletal muscle AN ELEVATED POSTPRANDIAL TRIGLYCERIDE (TG) excursion is a significant and independent risk factor for coronary heart disease (CHD) (15,21,31,50) and carotid atherosclerosis (6, 39). In addition, a decreased ability to oxidize lipid is considered to be a risk factor for weight gain (7, 51). It is therefore important to understand the factors that regulate the metabolic response to the ingestion of dietary fat. In this context, there are sexbased differences in the incidence of CHD (4, 22) and to a lesser extent obesity (28), which may be due in part to sex-based differences in postprandial lipoprotein metabolism. Specifically, after ingestion of a mixed meal, circulating TG levels have been shown to be significantly higher in men compared with premenopausal women (12, 18, 29) despite nearly identical glucose and insulin responses. This sex-based difference in the postprandial TG response does not appear to be explained by differences in premeal fasting TG levels (12, 18). The consequence of a lower T...

Sex differences in hormone-sensitive lipase expression, activity, and phosphorylation in skeletal muscle at rest and during exercise

“…In sex-comparative studies with healthy, young subjects representing a broad range of training status, the average percentage of body fat was 20 -30% in women and 9 -20% in men (2,8,9,15,16,26,36,37,47). The percentages of body fat in women (24.7 Ϯ 1.5%) and men (12.1 Ϯ 2.3%) in the present study are in agreement with these previous studies.…”

Effect of Sex and Impaired Glucose Tolerance on Organ-Specific Dietary Fatty Acid Metabolism in Humans

“…LPL expression is higher in subcutaneous adipose tissues in women (28), but there has been debate as to what organs are responsible for the apparent faster chylomicron-TG clearance in women. Our findings are more in favor of subcutaneous adipose tissues (23) than skeletal muscles (29) as the site explaining higher chylomicron-TG clearance in women. Delayed gastric emptying may also have contributed to the reduction in postprandial chylomicron-TG level and 18 F activity we observed in women (30).…”

Peripheral arterial disease, type 2 diabetes and postprandial lipidaemia: Is there a link?

“…Accordingly, it is worth speculating about whether arteriosclerotic disease in the legs could alter chylomicron metabolism, slowing it. With this in mind, consideration should be given to the study by Horton et al [81] , who showed that men have higher triglyceride concentrations than women because women posses a greater extractive capacity of triglycerides in adipose and muscle tissues in the lower limbs when they undergo a fatty breakfast. For some reason the catabolism of the chylomicrons in the legs is not negligible and an alteration in the circulation in the legs may worsen or slow this metabolism.…”