Alanine Aminopeptidase and Dipeptidyl Peptidase IV in Saliva of Chronic Periodontitis Patients

Background: Alanine aminopeptidase (ALAP) and dipeptidyl peptidase IV (DPPIV) are ectopeptidases that play a role in Collagen degradation and are thought to be involved in the destruction of periodontal tissue. This study compared the activities of salivary ALAP and DPPIV in patients with periodontitis and periodontally healthy subjects. The correlations of enzyme activities with clinical variables and the presence of Porphyromonas gingivalis were also evaluated. Methods: Whole saliva was collected from 30 periodontally healthy subjects, 30 localized chronic periodontitis (LCP) patients, and 30 generalized chronic periodontitis (GCP) patients to determine the activities of ALAP and DPPIV. The presence of P. gingivalis in subgingival plaque was detected by polymerase chain reaction. Periodontal clinical assessments included probing depth, clinical attachment level, and bleeding on probing. Results: The activities of DPPIV in the LCP and GCP groups were not significantly different from one another, but both groups had significantly higher enzyme activities than the periodontally healthy group (P=0.001). DPPIV activity was positively correlated with all clinical parameters and the prevalence of P. gingivalis. The ALAP activities were not significantly different among the three study groups. There was no significant correlation of ALAP activity with any of the clinical and bacterial parameters. Conclusion: DPPIV, but not ALAP, activity is associated with periodontitis and the presence of P. gingivalis. J Periodontol 2009,80:1809-1814.