Adipose tissue expression of interleukin-18 mRNA is elevated in subjects with metabolic syndrome and independently associated with fasting glucose

Wien Klin Wochenschr. 2011 Nov;123(21-22):650-4. doi: 10.1007/s00508-011-0028-6. Epub 2011 Aug 16.


Background: The metabolic syndrome (MetS) is a cluster of risk factors that are highly associated with increased risk for cardiovascular disease (CVD). Increased serum levels of plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6) and IL-18 have been reported to be associated with CVD. Recently, IL-18 has been shown to be predictive for cardiovascular events in subjects with MetS. We have investigated the expression of PAI-1, IL-6 and IL-18 in subcutaneous adipose tissue (AT) of subjects with (n = 22) and without (n = 36) MetS. Furthermore, we have analysed the expression of IL-18 in monocyte-derived macrophages (MDMs) in an in vitro model of hyperglycaemia.

Methods: We studied the expression of PAI-1, IL-6 and IL-18 in biopsies of subcutaneous adipose tissue using Real-time PCR. After isolation and cultivation of MDMs, expression of IL-18 was determined by Real-time PCR.

Results: Expression of IL-18 was increased in subcutaneous AT of subjects with MetS (p < 0.05). Multivariate analysis revealed fasting plasma glucose to be the only MetS component being independently associated with expression of IL-18 in AT (p < 0.05). Exposure to hyperglycaemia, increased in expression of IL-18 in MDMs (p < 0.01).

Conclusion: Our findings suggest that subjects with MetS have a particular inflammatory pattern in AT, possibly driven by fasting glucose. MDMs might - at least in part - be the cellular source of this increased expression. Together with recent reports, showing IL-18 to be predictive for cardiovascular events, our findings could provide the basis for further research of the role of IL-18 as a link and possible target in the association between MetS and atherosclerosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blood Glucose / metabolism*
  • Comorbidity
  • Fasting
  • Female
  • Humans
  • Inflammation / epidemiology*
  • Inflammation / metabolism*
  • Interleukin-18 / genetics
  • Interleukin-18 / metabolism*
  • Male
  • Metabolic Syndrome / epidemiology*
  • Metabolic Syndrome / metabolism*
  • Middle Aged
  • Norway / epidemiology
  • Prevalence
  • RNA, Messenger / metabolism
  • Risk Assessment
  • Risk Factors
  • Statistics as Topic


  • Blood Glucose
  • Interleukin-18
  • RNA, Messenger