Does lipoprotein(a) inhibit elastolysis in abdominal aortic aneurysms?
OBJECTIVE
to test the hypothesis that there is a negative association between serum levels of lipoprotein(a) (Lp(a)) and elastin-derived peptides (EDP) as well as matrix metalloproteinase (MMP)-9 activation in the aneurysm wall in patients with asymptomatic abdominal aortic aneurysms (AAA).


METHODS
from 30 patients operated for asymptomatic AAAs, preoperative serum samples and AAA biopsies were collected. Lp(a) (mg/L) and EDP (ng/ml) in serum were measured by enzyme linked immunosorbent assays. MMP-9 activity (arbitrary units) in the AAA wall was measured by gelatin zymography and the ratio: active MMP-9/total MMP-9 were calculated.


RESULTS
there was a significant negative correlation (Spearman's rho) between serum levels of Lp(a) and EDP (r= -0.707, p<0.001), as well as the share of activated MMP-9 (r= -0.461, p=0.01) in the AAA wall.


CONCLUSIONS
this preliminary study indicate that Lp(a) inhibit elastolysis in asymptomatic AAA.
D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000097:blood*; D004549:Elastin / Q000097:blood*; D004789:Enzyme Activation; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood / Q000502:physiology*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D008875:Middle Aged; D010455:Peptides / Q000097:blood*
D017270:Lipoprotein(a); D010455:Peptides; D004549:Elastin; D020780:Matrix Metalloproteinase 9