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Updated: Jul 12, 2026
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Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
Angiotensin II regulates adipocyte apolipoprotein E expression.
Poornima Rao1, Zhi Hua Huang, Theodore Mazzone
1Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
The Journal of Clinical Endocrinology and Metabolism
|September 6, 2007
Summary
Angiotensin II (AII) reduces apolipoprotein E (apoE) expression in fat cells, impacting lipid metabolism. This interaction between AII and apoE in adipose tissue is key for understanding metabolic health.
Area of Science:
- Endocrinology
- Metabolic Research
- Molecular Biology
Background:
- Obesity prevalence is rising, necessitating research into adipose tissue lipid metabolism regulation.
- Endogenous apolipoprotein E (apoE) in adipose tissue influences adipocyte lipid flux and gene expression.
- Adipose tissue is a known physiological target of angiotensin II (AII).
Purpose of the Study:
- To investigate the regulatory effect of angiotensin II (AII) on adipose tissue apolipoprotein E (apoE) expression.
Main Methods:
- Infusion of AII into mice and assessment of apoE expression in adipocytes and stromovascular fractions.
- Treatment of isolated human adipocytes (subcutaneous and omental) with AII.
- Evaluation of AII's effect using the AT(1) receptor blocker, valsartan.
Main Results:
- AII infusion significantly reduced apoE expression in mouse adipocytes but not in the stromovascular fraction.
- AII treatment significantly decreased cellular and secreted apoE in human adipocytes (20-60% reduction).
- Suppression of apoE expression by AII occurred in both nonobese and obese individuals' adipocytes, with lower baseline apoE in omental fat. Valsartan blocked AII's effect.
Conclusions:
- ApoE and renin-angiotensin system components are present in adipose tissue, affecting lipid metabolism and gene expression.
- The identified regulatory interaction between AII and apoE is crucial for understanding adipose tissue lipid homeostasis.
- This finding has significant implications for metabolic health and obesity research.
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