Serum MMP-1 and TIMP-1 levels are increased in patients with psoriatic arthritis and their siblings

Abstract
Objective. To determine matrix metalloproteinase-1 (MMP-1) and tissue-inhibitor metalloproteinase-1 (TIMP-1) serum levels in patients with psoriatic arthritis (PsA) and to compare this with their siblings and local blood donor controls. PsA is an interesting condition in which to study metalloproteinases because there are variations in the level of destructiveness, including a significant proportion of cases without destructive change. This is unlike rheumatoid arthritis (RA) which is more uniformly destructive and where MMP-1/TIMP-1 levels are known to be elevated.