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Insulin and metformin regulate circulating and adipose tissue chemerin
Bee K Tan1, Jing Chen, Syed Farhatullah
1Endocrinology and Metabolism Group, Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, Coventry, U.K.
Diabetes
|June 9, 2009
Summary
Serum and adipose tissue chemerin levels are elevated in women with polycystic ovary syndrome (PCOS). Insulin upregulates chemerin, while metformin treatment lowers it, suggesting a therapeutic target for PCOS.
Area of Science:
- Endocrinology
- Metabolic Syndrome
- Reproductive Medicine
Background:
- Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with metabolic dysfunction.
- Chemerin, a pro-inflammatory adipokine, has been implicated in metabolic and reproductive health.
- Understanding chemerin's role in PCOS is crucial for developing targeted therapies.
Purpose of the Study:
- To quantify chemerin levels in serum and adipose tissue of women with PCOS.
- To investigate the regulatory effects of insulin, metformin, and steroid hormones on chemerin expression.
- To assess the impact of metformin treatment on serum chemerin in PCOS patients.
Main Methods:
- Real-time RT-PCR and Western blotting for chemerin mRNA and protein.
- Enzyme-linked immunosorbent assay (ELISA) for serum chemerin quantification.
- In vivo insulin-glucose infusion and ex vivo adipose tissue explant studies.
Main Results:
- Women with PCOS exhibited significantly higher serum, subcutaneous, and omental adipose tissue chemerin.
- Hyperinsulinemia increased serum chemerin levels in vivo.
- Insulin stimulated, while metformin inhibited, adipose tissue chemerin production ex vivo.
- Metformin treatment led to a significant reduction in serum chemerin levels over 6 months.
- Insulin resistance was positively correlated with serum chemerin levels.
Conclusions:
- Serum and adipose tissue chemerin are elevated in women with PCOS.
- Insulin significantly upregulates chemerin in PCOS.
- Metformin effectively reduces serum chemerin levels in women with PCOS.
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