The PCL disintegrated in a matrix metalloproteinase (MMP) 1, 8, and particularly MMP-9 concentration dependent manner, with MMP-9 being an effective surrogate biomarker correlating with the activity of myositis.
Recently, we evaluated serum levels of MMP-9 and -2 (gelatinases) in mice experimentally infected with Trichinella spiralis or Trichinella pseudospiralis, which cause different degrees of myositis and we found their significant increase in the former and, at a lesser extent, in the latter, thus suggesting the possibility that these gelatinases, particularly MMP-9, represent a marker of inflammation.
Our results confirm that increased MMP9 immunoreactivity in muscle fibres is a common feature of all inflammatory myopathies and suggest that MMP2 and MMP7 cannot be implicated in the inflammatory events of FM.