Native C-reactive protein increases whereas modified C-reactive protein reduces atherosclerosis in apolipoprotein E-knockout mice.
BACKGROUND
C-reactive protein (CRP) may have proatherogenic but also vasoprotective properties. We tested the hypothesis that the configuration of CRP (pentameric, or native [nCRP], versus monomeric, or modified [mCRP]) determines these different characteristics in an in vivo model.


RESULTS
We investigated the effects of human nCRP and mCRP on the development of atherosclerosis in apolipoprotein E-knockout (ApoE(-/-)) mice. Treatment with nCRP for 8 weeks (2.5 mg/kg SC weekly) resulted in a 4-fold-higher mean aortic plaque area in 14-week-old female ApoE(-/-) mice compared with the saline controls. In contrast, mean plaque size was decreased by approximately 50% in mCRP-treated ApoE(-/-) mice (2.5 mg/kg SC weekly). Using immunohistochemistry, we report the natural presence of the mCRP antigen in saline controls. mCRP antigen was expressed in smooth muscle cells and extracellularly in the vicinity of the plaques to a similar level in both CRP-treated groups and saline controls. mCRP and ApoB colocalized with macrophages and were equally upregulated in all aortic plaques. Vascular cell adhesion molecule expression was increased, and CD154 and intercellular adhesion molecule showed a trend for higher expression in nCRP-treated compared with mCRP-treated mice. CD154 expression in the vessel wall and plaque size correlated significantly. mCRP-treated ApoE(-/-) exhibited higher serum levels of the antiinflammatory interleukin-10 compared with the other 2 groups.


CONCLUSIONS
Here, we show that mCRP and nCRP have opposite effects on atherosclerosis in ApoE(-/-) mice. These data may explain in part the conflicting activities previously reported for CRP in models of atherogenesis.
Schwedler
Susanne B
SB
Division of Nephrology, Department of Medicine, University of Würzburg, Würzburg, Germany. Pelleas@t-online.de
Amann
Kerstin
K
Wernicke
Konstanze
K
Krebs
Alexander
A
Nauck
Matthias
M
Wanner
Christoph
C
Potempa
Lawrence A
LA
Galle
Jan
J
D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency* / Q000378:metabolism; D050197:Atherosclerosis / Q000378:metabolism / Q000503:physiopathology* / Q000517:prevention & control*; D002097:C-Reactive Protein / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism* / Q000627:therapeutic use; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D018345:Mice, Knockout; D011994:Recombinant Proteins / Q000627:therapeutic use
D001057:Apolipoproteins E; D011994:Recombinant Proteins; D002097:C-Reactive Protein