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Updated: Jul 8, 2026
10:28
Isolation, Expansion, and Adipogenic Induction of CD34+CD31+ Endothelial Cells from Human Omental and Subcutaneous Adipose Tissue
Published on: July 17, 2018
Plasma adiponectin complexes have distinct biochemical characteristics.
Todd Schraw1, Zhao V Wang, Nils Halberg
1Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8549, USA.
Endocrinology
|January 19, 2008
Summary
Adiponectin circulates in distinct complexes, with the high-molecular-weight (HMW) form reduced in males, obese individuals, and during decreased production. These adiponectin forms do not interconvert in vivo, emphasizing secretion
Area of Science:
- Biochemistry
- Endocrinology
- Molecular Biology
Background:
- Adipocytes secrete adiponectin in distinct higher-order complexes: high-molecular-weight (HMW), hexamer, and trimer.
- These circulating complexes are biochemically distinct and stable, with minimal interchange observed.
- Understanding adiponectin complex dynamics is crucial for metabolic research.
Purpose of the Study:
- To validate a high-resolution gel filtration method for separating adiponectin complexes.
- To investigate the differential abundance of adiponectin complexes in various physiological states and species.
- To explore factors influencing adiponectin complex stability and formation.
Main Methods:
- High-resolution gel filtration chromatography for adiponectin complex separation.
- Analysis of recombinant and native adiponectin from human and murine samples.
- Assessment of adiponectin complex stability under varying pH, calcium concentrations, and disulfide bond conditions.
Main Results:
- The HMW adiponectin form is significantly reduced in males compared to females and in obese, insulin-resistant individuals versus lean, insulin-sensitive ones.
- Human serum generally shows higher trimer abundance compared to mouse serum.
- Reduced adiponectin production, due to obesity or genetic factors, selectively lowers circulating HMW adiponectin levels.
- Adiponectin HMW complexes are stable at basic pH but labile below pH 7, with differential calcium sensitivity and dependence on disulfide bond C39 for certain complex formations.
- In vivo studies confirmed no interconversion between adiponectin complexes over time.
Conclusions:
- Adiponectin complex distribution is influenced by sex, obesity, and insulin resistance.
- Secretion of distinct adiponectin complexes from adipocytes is a primary determinant of circulating levels.
- Adiponectin complex stability is regulated by pH, calcium, and disulfide bonds, with implications for its biological function.
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