Elevated serum levels of interleukin-18 are associated with insulin resistance in women with polycystic ovary syndrome

Endocrine. 2006 Jun;29(3):419-23. doi: 10.1385/ENDO:29:3:419.

Abstract

Overproduction of proinflammatory factors is associated with obesity and diabetes. Interleukin (IL)-18 as a member of IL-1 cytokine family is increased in obese, in diabetic, and even in polycystic ovary syndrome (PCOS) patients. In the present study we evaluated the association of serum IL-18 levels with insulin resistance in PCOS women. Forty-two PCOS women and 38 control subjects were enrolled in this study and matched with respect to age and body mass index (BMI). Serum IL-18 levels and hormones were measured for all subjects. Furthermore, euglycemic hyperinsulinemic clamp test was performed in selected 30 PCOS women and 11 control subjects. Serum IL-18 levels were elevated in PCOS women compared with the control (p = 0.033). IL-18 levels were positively correlated with homeostasis model assessment index (HOMA) beta index, which assesses beta cell function (p = 0.035), but were inversely correlated with clamp indices, which best represent insulin resistance status: M, Clamp ISI*100, and MCRg values (p = 0.006, 0.010, and 0.009 respectively). No correlation was found between IL-18 and age, BMI, waist-to-hip ratio (WHR), lipid profile, dehydroepiandrosterone-sulfate (DHEAS), sex hormone- binding globulin (SHBG), or fasting insulin levels. In conclusion, in the present study, serum IL-18 levels were significantly increased in PCOS women and firmly associated with insulin resistance displayed by euglycemic hyperinsulinemic clamp test. It indicates that IL-18 may be a contributing factor linking inflammation and insulin resistance in PCOS women.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Glucose / analysis
  • Body Mass Index
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Dehydroepiandrosterone / blood
  • Diabetes Mellitus, Type 2 / epidemiology
  • Female
  • Follicle Stimulating Hormone / blood
  • Glucose Clamp Technique / methods*
  • Humans
  • Insulin / blood
  • Insulin Resistance*
  • Interleukin-18 / blood*
  • Luteinizing Hormone / blood
  • Obesity / epidemiology
  • Polycystic Ovary Syndrome / blood*
  • Polycystic Ovary Syndrome / complications
  • Polycystic Ovary Syndrome / epidemiology*
  • Sex Hormone-Binding Globulin / analysis
  • Triglycerides / blood

Substances

  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Insulin
  • Interleukin-18
  • Sex Hormone-Binding Globulin
  • Triglycerides
  • Dehydroepiandrosterone
  • Luteinizing Hormone
  • Follicle Stimulating Hormone