title: Increased levels of C-reactive protein and interleukin-6 in hyperhomocysteinemic subjects.
abstract: OBJECTIVE
  Elevated plasma homocysteine concentration is considered to be an independent risk factor for cardiovascular disease. However, the mechanisms by which hyperhomocysteinemia are related to vascular disease are unclear. High-sensitivity C-reactive protein (CRP), a marker of inflammation, has been reported to be an independent predictor of future myocardial infarction among clinically healthy individuals. Interleukin (IL)-6 is a regulator of CRP and has a key role in initiation of inflammation. The aim of this study was to investigate whether individuals with increased plasma homocysteine concentrations have altered levels of serum CRP and IL-6.
  
  
  METHODS
  Serum concentrations of CRP and IL-6 were measured in 39 individuals with hyperhomocysteinemia and in 39 control subjects matched for gender, age and body mass index (BMI). In addition, the inflammatory effect of IL-6 on peripheral blood mononuclear cells was measured.
  
  
  RESULTS
  Compared to controls, hyperhomocysteinemic subjects have elevated serum levels of CRP and IL-6 (p < or =0.001 and p < 0.005, respectively). Importantly, this raised level of IL-6 was also seen in hyperhomocysteinemic individuals without accompanying hypercholesterolemia or cardiovascular disease. IL-6 increased the release of monocyte chemoattractant protein-1 from peripheral blood mononuclear cells, with particularly enhancing effects in cells from patients with hyperhomocysteinemia.
  
  
  CONCLUSIONS
  These data suggest that enhanced inflammation may be associated with homocysteine-related cardiovascular disease, possibly involving IL-6-related mechanisms.
authors.affiliation: The Lipid Clinic, Rikshospitalet University Hospital, NO-0027 Oslo, Norway. kirsten.holven@medisin.uio.no
authors.forename: K B
authors.initials: KB
authors.lastname: Holven
authors.forename: P
authors.initials: P
authors.lastname: Aukrust
authors.forename: K
authors.initials: K
authors.lastname: Retterstol
authors.forename: T A
authors.initials: TA
authors.lastname: Hagve
authors.forename: L
authors.initials: L
authors.lastname: Mørkrid
authors.forename: L
authors.initials: L
authors.lastname: Ose
authors.forename: M S
authors.initials: MS
authors.lastname: Nenseter
mesh_terms: D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000032:analysis*; D002318:Cardiovascular Diseases / Q000097:blood / Q000150:complications; D018932:Chemokine CCL2 / Q000378:metabolism; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000150:complications; D020138:Hyperhomocysteinemia / Q000097:blood* / Q000150:complications; D015850:Interleukin-6 / Q000097:blood*; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; D015850:Interleukin-6; D002097:C-Reactive Protein