Change in serum COMP concentration due to ambulatory load is not related to knee OA Status

Abstract

The aim of this study was to test the hypothesis that a change in serum cartilage oligomeric matrix protein (COMP) concentration is related to joint load during a 30-min walking exercise in patients with medial compartment knee osteoarthritis (OA) and in age-matched control subjects. Blood samples were drawn from 42 patients with medial compartment knee OA and from 41 healthy age-matched control subjects immediately before, immediately after, and 0.5, 1.5, 3.5, and 5.5 h after a 30-min walking exercise on a level outdoor walking track at self-selected normal speed. Serum COMP concentrations were determined using a commercial ELISA. Basic time-distance gait variables were recorded using an activity monitor. Joint loads were measured using gait analysis. Serum COMP concentrations increased immediately after the walking exercise (+6.3% and +5.6%; p < 0.001) and decreased over 5.5 h after the exercise (-11.1% and -14.6%; p < 0.040 and p = 0.001) in patients and control subjects, respectively. The magnitude of increase in COMP concentration did not differ between groups (p = 0.902) and did not correlate with any variables describing ambulatory loads at the joints of the lower extremity. These results, taken together with a previous study of a younger healthy population, suggest the possibility that the influence of ambulatory loads on cartilage turnover is dependent on age.

Different mechanical loading protocols influence serum cartilage oligomeric matrix protein levels in young healthy humans

“…However, there are several arguments against this concern. First, our results are in agreement with previous studies that reported a decrease in serum COMP concentration during rest, while in these studies the activity prior to the first blood sample was monitored (Andersson et al 2006;Mundermann et al 2005Mundermann et al , 2009. Second, the absolute COMP levels in our study are comparable to baseline levels in other studies after 15 min rest (Mundermann et al 2005) or unloading (Liphardt et al 2009).…”

“…Earlier investigations have demonstrated an increase in serum COMP concentration after cyclic mechanical loading in humans (Andersson et al 2006;Kim et al 2009;Mundermann et al 2005Mundermann et al , 2009Neidhart et al 2000), animals (Qi and Changlin 2006), explants (Piscoya et al 2005), and cell cultures . It was speculated that the increase in COMP after cyclic loading may reflect increased cartilage turnover and potential tissue damage (Andersson et al 2006;Kim et al 2009;Neidhart et al 2000).…”

Changes in the serum cartilage biomarker levels of healthy adults in response to an uphill walk

“…Changes in serum COMP level was also reported in other hyperphysiological activities, including weight-bearing exercises, running and marathon running. (3,14,15) The increase in COMP level was 200 km). (3,15) Table III shows the comparative information of the specific physiological activities that affect serum COMP level.…”

Moderate loading of the human osteoarthritic knee joint leads to lowering of intraarticular cartilage oligomeric matrix protein

“…Alternatively, the positive eVect of exercise could be exerted directly upon the cartilage. Exercise has been shown to cause rise in circulating cartilage markers like cartilage oligomeric matrix protein (COMP), aggrecan and CTX-II (C-terminal telopeptide of collagen II) all of which have been proposed as possible candidates for diagnosing and monitoring patients with OA [8][9][10][11] since they originate from the extracellular matrix of cartilage. The initial processes leading to loss of cartilage in OA are not well understood, though it has been recognized for some time that a low-grade inXammation is present in OA [12,13], presumably an eVect of as well as a reason for the pathological Wndings.…”