In:
American Journal of Physiology-Endocrinology and Metabolism, American Physiological Society, Vol. 296, No. 1 ( 2009-01), p. E165-E173
Abstract:
Upper body obese (UBO) subjects have greater cardiovascular disease risk than lower body obese (LBO) or lean subjects. Obesity is also associated with hypertriglyceridemia that may involve greater production and impaired removal of very-low-density lipoprotein (VLDL)-triglycerides (TG). In these studies, we assessed the impact of body composition on basal VLDL-TG production, VLDL-TG oxidation, and VLDL-TG storage. VLDL-TG kinetics were assessed in 10 UBO, 10 LBO, and 10 lean women using a bolus injection of [1- 14 C]VLDL-TG. VLDL-TG oxidation was measured by 14 CO 2 production (hyamine trapping) and VLDL-TG adipose tissue storage by fat biopsies. Insulin sensititvity was assessed by the hyperinsulinemic-euglycemic clamp technique and body composition by dual X-ray absorptiometry in combination with computed tomography. Hepatic VLDL-TG production was significantly greater in UBO than in lean women [(μmol/min) UBO: 64.8 (SD 40.0) vs. LBO: 42.5 (SD 25.6) vs. lean: 31.8 (SD 13.3), P = 0.04], whereas VLDL-TG oxidation was similar in the three groups and averaged 20% of resting energy expenditure [(μmol/min) UBO: 38.3 (SD 26.5) vs. LBO: 23.5 (SD 13.5) vs. lean: 21.1 (SD 9.7), P = 0.09] . In UBO women, more VLDL-TG was deposited in upper body subcutaneous fat [VLDL-TG redeposition in abdominal adipose tissue (μmol/min): UBO: 5.0 (SD 2.9) vs. LBO: 4.0 (SD 3.2) vs. lean: 1.3 (SD 1.0), ANOVA P = 0.01]; in LBO women, more VLDL-TG was deposited in femoral fat [VLDL-TG redeposition in femoral adipose tissue (μmol/min): UBO: 5.1 (SD 3.1) vs. LBO: 5.8 (SD 4.3) vs. lean: 2.3 (SD 1.5), ANOVA P = 0.04] . Only a small proportion of VLDL-TG (8–16%) was partitioned into redeposition in either group. We found that elevated VLDL-TG production without concomitant increased clearance via oxidation and adipose tissue redeposition contributes to hypertriglyceridemia in UBO women.
Type of Medium:
Online Resource
ISSN:
0193-1849
,
1522-1555
DOI:
10.1152/ajpendo.90675.2008
Language:
English
Publisher:
American Physiological Society
Publication Date:
2009
detail.hit.zdb_id:
1477331-4
detail.hit.zdb_id:
603841-4
SSG:
12
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