Abstract
Matrix metalloproteinase (MMP)-9 activity is controlled by the balance between MMP-9 and its major tissue inhibitor of metalloproteinases (TIMPs). We hypothesised whether Candida proteinases may affect local tissue inflammatory processes by modifying these molecules. The effects of sonicated cells and concentrated growth media of six Candida species on MMP-9, TIMP-1 and TIMP-2 were tested. Incubated samples were analysed by Western blot and detected by enhanced chemoluminescence techniques. The residual activity of degraded TIMP-1 was evaluated by a casein degradation assay. The proteinase activity of the microbial strains was also assessed by a fluorimetric assay, and the action of inhibitors on MMP-14 and Candida parapsilosis Cp2 was demonstrated. Cell fractions of both strains of C. parapsilosis exerted a weak ability to convert 92-kDa proMMP-9 to 86-kDa active form. Cell fractions of both strains of Candida albicans, C. parapsilosis Cp2, Candida glabrata reference strain, and both strains of Candida krusei fragmented TIMP-1 (28 kDa) to a 24-kDa species, which associated with reduced inhibitory activity on MMP-9 caseinolysis. Our findings indicate that Candida can participate in tissue inflammation by modifying the host's MMP-9 and their inhibitors. A rapid fluorimetric assay can be adapted for Candida proteinases.