title: Lipoprotein docosapentaenoic acid is associated with serum matrix metalloproteinase-9 concentration.
abstract: BACKGROUND
  Polyunsaturated fatty acids (PUFA) are thought to play important roles in inflammation. The n-3 series is considered as anti-inflammatory, and some studies have reported increased plasma n-3 polyunsaturated fatty acid pattern in chronic inflammatory conditions. In this study we sought to clarify relationships of the levels of arachidonic acid and the polyunsaturated n-3 fatty acid compositions of isolated LDL, HDL2 and HDL3 particles with matrix metalloproteinase-9 (MMP-9), a marker of inflammation.
  
  
  RESULTS
  The subjects were divided into two groups: those with lower and those with higher than the median serum MMP-9 concentration. In all lipoprotein fractions, the mean percentage of docosapentaenoic acid (C22:5n-3) was higher in the group of subjects with higher MMP-9 level than in those with lower serum MMP-9 concentration (P < 0.01 for all). Likewise, the ratio of docosapentaenoic acid to arachidonic acid (C20:4n-6) was higher in the subjects with higher MMP-9 compared with the lower MMP-9 group (P < 0.001 for all).
  
  
  CONCLUSIONS
  So far, the evidence for an anti-inflammatory role of the n-3 PUFA has come from dietary interventions. Our results were obtained from a free-living population and indicate that there is a positive correlation between n-3 docosapentaenoic acid and MMP-9. What had triggered the rise in MMP-9 is not known, since serum level of MMP-9 is raised in many inflammatory conditions. These findings may indicate an increased biosynthesis of n-3 polyunsaturated fatty acids in subclinical inflammation.
authors.affiliation: Department of Medical Biochemistry, Medical School, University of Tampere, Tampere, Finland. tiina.solakivi@uta.fi
authors.forename: Tiina
authors.initials: T
authors.lastname: Solakivi
authors.forename: Olli
authors.initials: O
authors.lastname: Jaakkola
authors.forename: Anne
authors.initials: A
authors.lastname: Kalela
authors.forename: Mari
authors.initials: M
authors.lastname: Pispa
authors.forename: Anne
authors.initials: A
authors.lastname: Salomäki
authors.forename: Terho
authors.initials: T
authors.lastname: Lehtimäki
authors.forename: Matti
authors.initials: M
authors.lastname: Höyhtyä
authors.forename: Hannu
authors.initials: H
authors.lastname: Jokela
authors.forename: Seppo T
authors.initials: ST
authors.lastname: Nikkari
mesh_terms: D000328:Adult; D005231:Fatty Acids, Unsaturated / Q000097:blood*; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood* / Q000145:classification; D008875:Middle Aged
chemical_list: D005231:Fatty Acids, Unsaturated; D008074:Lipoproteins; D020780:Matrix Metalloproteinase 9; C026219:docosapentaenoic acid