Do MMP-1 levels of gingival fibroblasts have a role in the gingival overgrowth of cyclosporine-treated patients?

The aim of this study was to compare the matrix metalloproteinase-1 (MMP-1) levels in gingival fibroblast cultures derived from two groups of renal transplant patients receiving cyclosporine (CsA) who exhibit gingival overgrowth and who have healthy periodontium. Gingival fibroblasts obtained from four patients with CsA-induced gingival overgrowth (CsA-GO) and four patients who receive CsA but have healthy periodontium were incubated with increasing concentrations of CsA and cultured for 72 hours. Expression levels of MMP-1 in all the groups were measured four times at 0, 24, 48, and 72 hours by the Rapid Collagenase Assay Kit. No significant difference was seen at baseline. As the CsA concentration and the duration in the cell media increased, the CsA-GO showed that fibroblasts displayed significantly suppressed MMP-1 levels with respect to the baseline, at which fibroblasts from CsA patients with healthy periodontium exhibited the same result as at the highest CsA concentration. Results of this study indicated that CsA therapy did not have a significant effect on MMP-1 levels. Since the overall pathogenesis of drug-induced gingival hyperplasia has been accepted as multifactorial, down-regulation of MMP-1 expression may play a minor role.