Low plasma insulin-like growth factor-1 levels are associated with reduced insulin sensitivity and increased insulin secretion in nondiabetic subjects

Succurro, E.; Andreozzi, F.; Marini, M.A.; Lauro, R.; Hribal, M.L.; Perticone, F.; Sesti, G.

doi:10.1016/j.numecd.2008.12.011

« Previous Next »Nutrition, Metabolism & Cardiovascular Diseases
Volume 19, Issue 10 , Pages 713-719, December 2009

Low plasma insulin-like growth factor-1 levels are associated with reduced insulin sensitivity and increased insulin secretion in nondiabetic subjects

E. Succurro
- Department of Experimental and Clinical Medicine, University Magna-Græcia of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
F. Andreozzi
- Department of Experimental and Clinical Medicine, University Magna-Græcia of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
M.A. Marini
- Department of Internal Medicine, University of Rome-Tor Vergata, Rome, Italy
R. Lauro
- Department of Internal Medicine, University of Rome-Tor Vergata, Rome, Italy
M.L. Hribal
- Department of Experimental and Clinical Medicine, University Magna-Græcia of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
F. Perticone
- Department of Experimental and Clinical Medicine, University Magna-Græcia of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
G. Sesti
- Department of Experimental and Clinical Medicine, University Magna-Græcia of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
- Corresponding author. Tel.: +39 0961 3647204; fax: +39 0961 3647192.

Received 4 August 2008; received in revised form 17 November 2008; accepted 29 December 2008. published online 06 April 2009.

Abstract

Background and aim

Weight gain is associated with a decline in insulin sensitivity and a compensatory increase in insulin secretion. IGF-1 is a plausible candidate to explain these divergent phenomena. In this cross-sectional study, we analyzed the relationship between IGF-1 levels, insulin sensitivity and secretion in 110 nondiabetic subjects with a wide range of BMI to verify this hypothesis.

Methods and results

Subjects underwent OGTT, IVGTT and euglycemic-hyperinsulinemic clamp. HOMA-beta, IVGTT-derived and OGTT-derived indexes for first-phase and second-phase insulin secretion were higher in obese as compared with overweight and normal-weight groups, while glucose disposal was lower. IGF-1 levels were negatively correlated with IVGTT-derived and OGTT-derived indexes first-phase and second-phase insulin secretion, and positively correlated with glucose disposal. These correlations were no longer significant after adjustment for BMI.

In a multivariate analysis, the variables associated with glucose disposal were IGF-1, age, triglycerides, and 2-h post-load glucose accounting for 23.4% of its variation. When BMI was entered into the model, the variables associated with glucose disposal were triglycerides, 2-h post-load glucose and BMI accounting for 27.2% of variation. In a multivariate analysis, the only variable associated with IVGTT-derived first-phase and second-phase insulin secretion was IGF-1 accounting for 10.4% and 15.1% of variation, respectively. When BMI was entered into the model, it became the only variable associated with both first-phase and second-phase insulin secretion accounting for 25.7% and 37.6% of variation, respectively.