Matrix Metalloproteinase-2 May Be Involved With Increased Bone Loss Associated With Experimental Periodontitis and Smoking:: A Study in Rats

• Autores: João Batista César-Neto, Ana Paula de Souza, Deise Barbieri, Heitor Moreno Jr., Enilson Antonio Sallum
• Localización: Journal of periodontology, ISSN 0022-3492, Vol. 75, Nº. 7, 2004, págs. 995-1000
• Idioma: inglés
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• Resumen

  • Background: Smoking has been associated with periodontitis severity and is considered a risk factor for its development. It has been reported that matrix metalloproteinase (MMP) produced by host cells plays a major role in periodontal tissue destruction. Thus, the present study tested, in rats, the hypothesis that local increased levels of MMP-2 would be associated with the enhanced periodontitis-related bone loss after intermittent cigarette smoke inhalation (CSI).

    Methods: Twenty-seven adult male Wistar rats were used. A ligature was placed around one of the mandibular first molars of each animal and they were randomly assigned to the following control (N = 13) or CSI (N = 14) group. Sixty days later, the animals were sacrificed, the gingival tissues harvested, and the specimens processed for decalcified sections. Extracts from the gingival tissues were prepared and assayed for MMP-2 expression.

    Results: Intergroup comparisons (unligated sites) showed that CSI might directly affect alveolar bone (0.16 ± 0.03 mm2 versus 0.24 ± 0.09 mm2 for non-smokers and smokers, respectively; P = 0.001). Moreover, CSI significantly enhanced bone loss resulting from experimental periodontitis (0.64 ± 0.36 mm2 versus 1.50 ± 0.50 mm2 for non-smokers and smokers, respectively; P <0.05). In addition, zymography demonstrated that CSI also enhanced both MMP-2 levels and activity in the gingival tissues around ligated teeth.

    Conclusion: Within the limits of the present investigation, it can be assumed that the effect of CSI on MMP-2 levels and activity may account for the increased periodontitis progression rate observed in smokers. J Periodontol 2004;75:995-1000.