TY - JOUR
T1 - High levels of inflammatory biomarkers are associated with increased allele-specific apolipoprotein(a) levels in African-Americans
AU - Erdembileg, Anuurad
AU - Rubin, Jill
AU - Chiem, Alan
AU - Tracy, Russell P.
AU - Pearson, Thomas A.
AU - Berglund, Lars
PY - 2008/4
Y1 - 2008/4
N2 - Background: A role of inflammation for cardiovascular disease (CVD) is established. Lipoprotein(a) [Lp(a)] is an independent CVD risk factor where plasma levels are determined by the apolipoprotein(a) [apo(a)] gene, which contains inflammatory response elements. Design: We investigated the effect of inflammation on allele-specific apo(a) levels in African-Americans and Caucasians. We determined Lp(a) levels, apo(a) sizes, allele-specific apo(a) levels, fibrinogen and C-reactive protein (CRP) levels in 167 African-Americans and 259 Caucasians. Results: Lp(a) levels were increased among African-Americans with higher vs. lower levels of CRP [<3 vs. ≥3 mg/liter (143 vs. 108 nmol/liter), P = 0.009] or fibrinogen (<340 vs. ≥340 mg/liter, P = 0.002). We next analyzed allele-specific apo(a) levels for different apo(a) sizes. No differences in allele-specific apo(a) levels across CRP or fibrinogen groups were seen among African-Americans or Caucasians for small apo(a) sizes (<22 kringle 4 repeats). Allele-specific apo(a) levels for medium apo(a) sizes (22-30 kringle 4 repeats) were significantly higher among African-Americans, with high levels of CRP or fibrinogen compared with those with low levels (88 vs. 67 nmol/liter, P = 0.014, and 91 vs. 59 nmol/liter, P = 0.0001, respectively). No difference was found for Caucasians. Conclusions: Increased levels of CRP or fibrinogen are associated with higher allele-specific medium-sized apo(a) levels in African-Americans but not in Caucasians. These findings indicate that proinflammatory conditions result in a selective increase in medium-sized apo(a) levels in African-Americans and suggest that inflammation-associated events may contribute to the interethnic difference in Lp(a) levels between African-Americans and Caucasians.
AB - Background: A role of inflammation for cardiovascular disease (CVD) is established. Lipoprotein(a) [Lp(a)] is an independent CVD risk factor where plasma levels are determined by the apolipoprotein(a) [apo(a)] gene, which contains inflammatory response elements. Design: We investigated the effect of inflammation on allele-specific apo(a) levels in African-Americans and Caucasians. We determined Lp(a) levels, apo(a) sizes, allele-specific apo(a) levels, fibrinogen and C-reactive protein (CRP) levels in 167 African-Americans and 259 Caucasians. Results: Lp(a) levels were increased among African-Americans with higher vs. lower levels of CRP [<3 vs. ≥3 mg/liter (143 vs. 108 nmol/liter), P = 0.009] or fibrinogen (<340 vs. ≥340 mg/liter, P = 0.002). We next analyzed allele-specific apo(a) levels for different apo(a) sizes. No differences in allele-specific apo(a) levels across CRP or fibrinogen groups were seen among African-Americans or Caucasians for small apo(a) sizes (<22 kringle 4 repeats). Allele-specific apo(a) levels for medium apo(a) sizes (22-30 kringle 4 repeats) were significantly higher among African-Americans, with high levels of CRP or fibrinogen compared with those with low levels (88 vs. 67 nmol/liter, P = 0.014, and 91 vs. 59 nmol/liter, P = 0.0001, respectively). No difference was found for Caucasians. Conclusions: Increased levels of CRP or fibrinogen are associated with higher allele-specific medium-sized apo(a) levels in African-Americans but not in Caucasians. These findings indicate that proinflammatory conditions result in a selective increase in medium-sized apo(a) levels in African-Americans and suggest that inflammation-associated events may contribute to the interethnic difference in Lp(a) levels between African-Americans and Caucasians.
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U2 - 10.1210/jc.2007-2416
DO - 10.1210/jc.2007-2416
M3 - Article
C2 - 18252779
AN - SCOPUS:42049104360
VL - 93
SP - 1482
EP - 1488
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 4
ER -