title: IL-6 and its receptors in coronary artery disease and acute myocardial infarction.
abstract: Biomarkers such as interleukin-6 (IL-6), soluble interleukin-6 receptor (sIL-6R), and high sensitive C-reactive protein (hsCRP) have been reported to be elevated in acute myocardial infarction (AMI). The aim of this study is to determine the relationship between these markers during AMI, as well as their relationship to clinical parameters in an effort to discern their predictive potential in cardiac events. Serum was collected from 73 patients with; AMI, stable coronary artery disease (CAD), and controls during cardiac catheterization. Biomarker levels were determined and correlated with clinical data. IL-6 (11.75pg/ml, P<0.05) and sIL-6R (41,340pg/ml, P=0.05) were elevated in AMI compared with CAD and controls. At presentation, hsCRP was elevated in AMI patients (4.69mg/L) compared to controls (2.69mg/L, P<0.05); however, there was a significant decrease in hsCRP between AMI (4.69mg/L) and CAD patients (7.4mg/L, P<0.05). After 24h post-AMI hsCRP levels were increased compared to stable CAD (60.46mg/L, P<0.05) and were preceded by increased IL-6 at presentation. Soluble Gp130 (sGp130) showed no significant change between AMI, CAD, and control patients. However, sGp130 positively correlated with peak troponin in AMI (R=0.587, P<0.01), and negatively correlated with previous AMI (R=-0.382, P<0.05). Circulating monocyte mRNA expression isolated from selected AMI patients showed an increase in IL-6 mRNA (5.28-fold, P<0.01) and a decrease in both IL-6R (0.374-fold, P<0.01) and sGp130 mRNA (0.38-fold, P<0.01) as compared to CAD and controls. Results demonstrate that IL-6 and sIL-6R are associated with AMI and cardiac injury. These data support the hypothesis that trans-IL-6 receptor binding may alter intracellular signaling, and blocking of IL-6 receptor binding may be pathogenic in AMI. These data may be predictive of mechanism(s) by which plaques become unstable and rupture.
authors.affiliation: Experimental Immunology, Research in Cardiovascular Disease Laboratory, The University of Nebraska Medical Center, Wittson Hall Room 3004, 986350 Nebraska Medical Center, Omaha, NE 68198-6350, United States. danderso@unmc.edu
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Anderson
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Poterucha
authors.forename: Ted R
authors.initials: TR
authors.lastname: Mikuls
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Duryee
authors.forename: Robert P
authors.initials: RP
authors.lastname: Garvin
authors.forename: Lynell W
authors.initials: LW
authors.lastname: Klassen
authors.forename: Scott W
authors.initials: SW
authors.lastname: Shurmur
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Thiele
mesh_terms: D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000097:blood* / Q000235:genetics*; D050822:Cytokine Receptor gp130 / Q000097:blood; D003710:Demography; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D015850:Interleukin-6 / Q000097:blood* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009203:Myocardial Infarction / Q000097:blood* / Q000235:genetics*; D019947:Receptors, Interleukin-6 / Q000097:blood* / Q000235:genetics; D012044:Regression Analysis
chemical_list: C508600:IL6 protein, human; C508603:IL6R protein, human; D015850:Interleukin-6; D019947:Receptors, Interleukin-6; D050822:Cytokine Receptor gp130; D002097:C-Reactive Protein