Incretin hormone secretion in women with polycystic ovary syndrome: roles of obesity, insulin sensitivity, and treatment with metformin

TY - JOUR

T1 - Incretin hormone secretion in women with polycystic ovary syndrome

T2 - roles of obesity, insulin sensitivity, and treatment with metformin

AU - Svendsen, Pernille Fog

AU - Nilas, Lisbeth

AU - Madsbad, Sten

AU - Holst, Jens Juul

PY - 2009/5

Y1 - 2009/5

N2 - In normal subjects, the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are responsible for 70% of the insulin response during a meal; but in diabetic subjects and other insulin-resistant conditions, the incretin effect is impaired. Polycystic ovary syndrome (PCOS) is associated with insulin resistance, and the pathophysiologic mechanisms behind PCOS resemble those of type 2 diabetes mellitus; therefore, women with PCOS may have alterations in the incretin hormone response. Metformin is widely used in the treatment of both type 2 diabetes mellitus and PCOS. Metformin may exert some of its effect on glucose metabolism by increasing GLP-1 biosynthesis and secretion and thereby increasing the incretin effect. The objective of the study was to measure incretin hormone secretion in women with PCOS and to evaluate the effect of metformin treatment. Cross-sectional comparison of 40 women with PCOS (19 lean and 21 obese) and 26 healthy control women (9 lean and 17 obese) and longitudinal evaluation of the effects of 8 months of metformin 1000 mg twice daily in women with PCOS were performed. Plasma concentrations of GIP and GLP-1 were determined frequently during a 75-g glucose tolerance test, and insulin sensitivity was evaluated by the euglycemic hyperinsulinemic clamp. The incretin hormone response did not differ between subjects with and without PCOS. Subgroup analysis showed lower GIP (area under the curve [AUC]) levels in obese women with PCOS compared with obese control women (P < .05) and compared with lean women with PCOS (P < .05). Metformin increased GIP (AUC) and GLP-1 (AUC) in lean women with PCOS (P < .05), and a similar trend was seen in the obese women (P = .07). The GIP secretion is attenuated in obese women with PCOS, whereas treatment with metformin increases the levels of both GIP and GLP-1 in women with PCOS.

AB - In normal subjects, the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are responsible for 70% of the insulin response during a meal; but in diabetic subjects and other insulin-resistant conditions, the incretin effect is impaired. Polycystic ovary syndrome (PCOS) is associated with insulin resistance, and the pathophysiologic mechanisms behind PCOS resemble those of type 2 diabetes mellitus; therefore, women with PCOS may have alterations in the incretin hormone response. Metformin is widely used in the treatment of both type 2 diabetes mellitus and PCOS. Metformin may exert some of its effect on glucose metabolism by increasing GLP-1 biosynthesis and secretion and thereby increasing the incretin effect. The objective of the study was to measure incretin hormone secretion in women with PCOS and to evaluate the effect of metformin treatment. Cross-sectional comparison of 40 women with PCOS (19 lean and 21 obese) and 26 healthy control women (9 lean and 17 obese) and longitudinal evaluation of the effects of 8 months of metformin 1000 mg twice daily in women with PCOS were performed. Plasma concentrations of GIP and GLP-1 were determined frequently during a 75-g glucose tolerance test, and insulin sensitivity was evaluated by the euglycemic hyperinsulinemic clamp. The incretin hormone response did not differ between subjects with and without PCOS. Subgroup analysis showed lower GIP (area under the curve [AUC]) levels in obese women with PCOS compared with obese control women (P < .05) and compared with lean women with PCOS (P < .05). Metformin increased GIP (AUC) and GLP-1 (AUC) in lean women with PCOS (P < .05), and a similar trend was seen in the obese women (P = .07). The GIP secretion is attenuated in obese women with PCOS, whereas treatment with metformin increases the levels of both GIP and GLP-1 in women with PCOS.

KW - Adult

KW - Blood Glucose

KW - Cross-Sectional Studies

KW - Female

KW - Gastric Inhibitory Polypeptide

KW - Glucagon-Like Peptide 1

KW - Glucose

KW - Glucose Clamp Technique

KW - Glucose Tolerance Test

KW - Humans

KW - Hypoglycemic Agents

KW - Insulin

KW - Insulin Resistance

KW - Longitudinal Studies

KW - Metformin

KW - Obesity

KW - Polycystic Ovary Syndrome

U2 - 10.1016/j.metabol.2008.11.009

DO - 10.1016/j.metabol.2008.11.009

M3 - Journal article

C2 - 19375579

SN - 0026-0495

VL - 58

SP - 586

EP - 593

JO - Metabolism

JF - Metabolism

IS - 5

ER -