Altered relationship between MMP-8 and TIMP-2 in gingival crevicular fluid in adolescents with Down's syndrome

Background and Objective: Periodontitis is more frequently found in subjects with Down's syndrome. The aim was to investigate whether the relationship between MMPs and TIMPs) in the gingival crevicular fluid of subjects with Down's syndrome is altered compared with controls. Material and Methods: Twenty-one adolescents with Down's syndrome and gingivitis (DS-G), 12 subjects with Down's syndrome and periodontitis (DS-P), 26 controls with gingivitis (HC-G) and eight controls with periodontitis (HC-P) were clinically examined. All patients were between 11 and 20 years of age. Gingival crevicular fluid was collected from each subject and the concentrations of MMPs (2, 3, 8, 9 and 13) and TIMPs (1, 2 and 3) (expressed as pg/mu L adjusted for volume* of gingival crevicular fluid) were determined using multianalyte kits from R&D Systems. Results: The concentrations of MMP-2, MMP-3, MMP-8, MMP-9 and TIMP-2 in gingival crevicular fluid were significantly higher (p < 0.005) in the DS-G group compared with the HC-G group. The correlation coefficient between MMP-8 and TIMP-2 differed significantly (p = 0.006) between the DS-G group and the HC-G group. On the contrary, the correlation coefficients between MMPs and TIMPs did not differ significantly between the DS-P group and the HC-P group. However, the DS-P group exhibited a significantly lower concentration of TIMP-2 in the gingival crevicular fluid compared with the HC-P group. Conclusion: Down's syndrome subjects with gingivitis exhibit higher concentrations of MMPs in gingival crevicular fluid with an altered relationship between MMP-8 and TIMP-2, which might impair the periodontal tissue turnover.