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Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis
Published on: June 3, 2016
Hypoxia induces apelin expression in human adipocytes
K Geiger1, A Muendlein, N Stark
1Vorarlberg Institute for Vascular Investigation and Treatment, Feldkirch, Austria.
Hormone and Metabolic Research = Hormon- Und Stoffwechselforschung = Hormones Et Metabolisme
|March 31, 2011
Summary
Hypoxia, or low oxygen, significantly increases the expression and secretion of the adipokine apelin in human fat cells. This response is mediated by HIF-1α, offering new insights into obesity and insulin resistance.
Area of Science:
- Endocrinology and Metabolism
- Cellular Biology
- Physiology
Background:
- Adipokines are crucial in obesity and insulin resistance.
- Adipose tissue hypoxia disrupts adipokine expression.
- The impact of hypoxia on apelin in human adipocytes is not well understood.
Purpose of the Study:
- To investigate the effect of hypoxia on apelin expression in human adipocytes.
- To elucidate the role of hypoxia-inducible factor 1-alpha (HIF-1α) in this process.
Main Methods:
- Differentiated human Simpson-Golabi-Behmel syndrome (SGBS) adipocytes were exposed to hypoxic conditions (1% O2) or chemical hypoxia (CoCl2).
- Gene expression was analyzed using real-time PCR.
- Apelin secretion was quantified via ELISA.
Main Results:
- Hypoxia significantly upregulated mRNA expression of leptin and apelin.
- Hypoxia significantly downregulated adiponectin mRNA expression.
- Secreted apelin protein levels were elevated under hypoxic conditions.
- Hypoxia-induced apelin mRNA expression was dependent on HIF-1α.
Conclusions:
- Apelin expression and secretion are strongly induced by hypoxia in human adipocytes.
- The early hypoxic response of apelin induction is mediated by HIF-1α.
- Findings provide novel insights into adipokine regulation in metabolic diseases.
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