title: Serum- and HDL3-serum amyloid A and HDL3-LCAT activity are influenced by increased CVD-burden.
abstract: BACKGROUND
  High density lipoproteins (HDL) protect against cardiovascular disease (CVD). However, increased serum amyloid-A (SAA) related inflammation may negate this property. This study investigated if SAA was related to CVD-burden.
  
  
  METHODS
  Subjects referred to the rapid chest pain clinic (n = 240) had atherosclerotic burden assessed by cardiac computerised tomography angiography. Subjects were classified as: no-CVD (n = 106), non-obstructive-CVD, stenosis<50% (n = 58) or moderate/significant-CVD, stenosis ≥50% (n = 76). HDL was subfractionated into HDL2 and HDL3 by rapid-ultracentrifugation. SAA-concentration was measured by ELISA and lecithin cholesterol acyltransferase (LCAT) activity measured by a fluorimetric assay.
  
  
  RESULTS
  We illustrated that serum-SAA and HDL3-SAA-concentration were higher and HDL3-LCAT-activity lower in the moderate/significant-CVD-group, compared to the no-CVD and non-obstructive-CVD-groups (percent differences: serum-SAA, +33% & +30%: HDL3-SAA, +65% and +39%: HDL3-LCAT, -6% & -3%; p < 0.05 for all comparisons). We also identified a positive correlation between serum-SAA and HDL3-SAA (r = 0.698; p < 0.001) and a negative correlation between HDL3-SAA and HDL3-LCAT-activity (r = -0.295; p = 0.003), while CVD-burden positively correlated with serum-SAA (r = 0.150; p < 0.05) and HDL3-SAA (r = 0.252; p < 0.001) and negatively correlated with HDL3-LCAT-activity (r = -0.182; p = 0.006). Additionally, multivariate regression analysis adjusted for age, gender, CRP and serum-SAA illustrated that HDL3-SAA was significantly associated with modifying CVD-risk of moderate/significant CVD-risk (p < 0.05).
  
  
  CONCLUSIONS
  This study has demonstrated increased SAA-related inflammation in subjects with moderate/significant CVD-burden, which appeared to impact on the antiatherogenic potential of HDL. We suggest that SAA may be a useful biomarker to illustrate increased CVD-burden, although this requires further investigation.
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom. Electronic address: J.McEneny@qub.ac.uk.
authors.forename: Jane
authors.initials: J
authors.lastname: McEneny
authors.affiliation: Cardiovascular Research Department, Ulster Hospital, Belfast, United Kingdom.
authors.forename: Peter
authors.initials: P
authors.lastname: McKavanagh
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Edmund
authors.initials: E
authors.lastname: York
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Nida
authors.initials: N
authors.lastname: Nadeem
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Harbinson
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: Stevenson
authors.affiliation: Cardiovascular Research Department, Ulster Hospital, Belfast, United Kingdom.
authors.forename: Peter
authors.initials: P
authors.lastname: Ball
authors.affiliation: Cardiovascular Research Department, Ulster Hospital, Belfast, United Kingdom.
authors.forename: Lisa
authors.initials: L
authors.lastname: Lusk
authors.affiliation: Clinical Biochemistry, Ulster Hospital, Belfast, United Kingdom.
authors.forename: Thomas
authors.initials: T
authors.lastname: Trinick
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Young
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: McKay
authors.affiliation: Cardiovascular Research Department, Ulster Hospital, Belfast, United Kingdom.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Donnelly
mesh_terms: D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000000981:diagnostic imaging / Q000453:epidemiology*; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood*; D053440:Lipoproteins, HDL3 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood*; D000685:Serum Amyloid A Protein / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D008075:Lipoproteins, HDL; D053440:Lipoproteins, HDL3; D000685:Serum Amyloid A Protein; D007862:Phosphatidylcholine-Sterol O-Acyltransferase
keywords: CVD-Burden; HDL; LCAT activity; Serum amyloid A