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Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion
Published on: May 10, 2018
The relationship between insulin sensitivity and insulin-like growth factor-binding protein-1
1Department of Medicine and Obstetrics and Gynecology, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
Summary
Women with polycystic ovary syndrome (PCOS) have lower insulin sensitivity and insulin-like growth factor-binding protein-1 (IGFBP-1) levels. Insulin sensitivity significantly predicts IGFBP-1 concentrations in PCOS patients, suggesting a role in the condition's pathophysiology.
Area of Science:
- Endocrinology
- Reproductive Medicine
Background:
- Insulin regulates insulin-like growth factor-binding protein-1 (IGFBP-1).
- Insulin resistance is a key feature of polycystic ovary syndrome (PCOS).
Purpose of the Study:
- To investigate the relationship between insulin sensitivity (S1) and circulating IGFBP-1 concentrations in women with and without PCOS.
Main Methods:
- A case-control study comparing 15 women with PCOS and 10 age- and weight-matched controls.
- Insulin sensitivity (S1) measured using the frequently sampled intravenous glucose tolerance test (FSIGT) minimal model technique.
- Measurement of IGFBP-1, IGF-I, growth hormone, testosterone, DHEA, and DHEAS levels.
Main Results:
- Women with PCOS exhibited significantly lower S1 and IGFBP-1 levels compared to controls.
- In PCOS patients, IGFBP-1 concentrations were negatively correlated with body mass index (BMI) and positively with S1.
- S1 remained a significant predictor of IGFBP-1 levels even after controlling for BMI.
Conclusions:
- Insulin sensitivity is a significant determinant of IGFBP-1 levels in women with PCOS.
- Reduced IGFBP-1 concentrations may contribute to the pathophysiology of PCOS by altering insulin-like growth factor (IGF) delivery in insulin-resistant individuals.
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