Abstract |
High-density lipoprotein (HDL) particles without apolipoprotein A-II (Lp A-I) may be more anti-atherogenic than HDL with apo A-II (Lp A-I/AII) and Lp A-I is reported selectively to be reduced in cases of intra- abdominal obesity. We explored the mechanisms of this reduction by studying the turnover of Lp A-I and Lp A-I/A-II in postmenopausal women well characterized for total body, regional and sub-regional adiposity by body mass index (BMI), truncal girth ratio, and abdominal magnetic resonance imaging (MRI), respectively. We tested for possible cause-effect relationships by measuring inter-correlations among these variables. Intra-abdominal fat area correlated strongly and positively with the fractional catabolic rate (FCR) of Lp A-I (r=0.98, P=0.003). Intra-abdominal fat only showed a non-significant trend toward correlation with the FCR of Lp A-I/A-II (r=0.84, P=0.07), and had no correlation with the production or transport rate (TR) of either Lp A-I or Lp A-I/A-II (r=0.48 and 0.02, respectively, P>0.1). Subjects were studied both with and without estrogen replacement, allowing exploration of a possible interaction of adiposity with estrogen effects on HDL turnover. Response of HDL turnover to estrogen did not correlate with adiposity, except for a parameter of waist to hip ratio (WHR), which predicted the increase in LP A-I TR with estrogen (r=0.84, P=0.04). We conclude that intra-abdominal fat may lower HDL levels by increasing the FCR of Lp A-I, suggesting a mechanism by which central adiposity may be proatherogenic.
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Authors | Zoltan Vajo, James G Terry, Eliot A Brinton |
Journal | Atherosclerosis
(Atherosclerosis)
Vol. 160
Issue 2
Pg. 495-501
(Feb 2002)
ISSN: 0021-9150 [Print] Ireland |
PMID | 11849676
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Apolipoprotein A-I
- Apolipoprotein A-II
- Lipoproteins, HDL
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Topics |
- Abdomen
(pathology)
- Adipose Tissue
(pathology)
- Apolipoprotein A-I
(metabolism)
- Apolipoprotein A-II
(metabolism)
- Body Mass Index
- Estrogen Replacement Therapy
- Female
- Humans
- Lipoproteins, HDL
(metabolism)
- Middle Aged
- Obesity
(metabolism, pathology)
- Postmenopause
(metabolism)
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