Introduction: Periodontitis is an inflammatory bacterial disease, leading to progressive destruction of the tooth- supporting apparatus and to tooth loss. The dysregulation between an activity of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMP) plays an important role in a development and progression of inflammation .
Objective: To study features of TIMP1 expression in patients with different types of periodontitis.
Material and methods: A gingival biopsy was analyzed from patients with aggressive (AgP, n=16), chronic simplex (CSP, n=3), chronic complex (CCP, n=23) periodontitis, and a control group (n=6). Morphometric and statistical analysis of the TIMP1 expression was performed using AperioImage Scope v188.8.131.5243, Statistica10, p<0.05.
Results: The expression of TIMP1 in the biopsy was obtained in all patients with different forms of periodontitis and in the control group, both in the gingival epithelium and stroma. There was a statistically significant decrease in the intensity and proportion of strong and moderate intensity pixels of epithelial and stromal expression of TIMP1 in all groups of periodontitis compared to healthy tissue (p˂0.05). At the same time, the lowest values of positivity and intensity of both epithelial and stromal expression were found in the CSP group, increased in the AgP (p=0.003 and p=0.0006) and were highest in the CCP group (p=0.001). In the AgP group, compared with the CCP, there were lower levels of intensity parameters (U=27736 and U=23502, p˂0.001) and the proportion of strong and moderate intensity pixels (U=28164/p=0.001 and U=26273/p=0.022) of epithelial and stromal expression of TIMP1, respectively.
Conclusions: A decrease in epithelial and stromal expression of TIMP1 with a dysregulation of MMPs expression [2-3] in different types of periodontitis compared to the healthy tissue supports its importance in the pathogenesis of periodontal inflammation. At the same time, an even greater decrease in TIMP1 expression in the group of aggressive periodontitis compared to chronic complex periodontitis may explain the high aggressiveness of its course, loss of alveolar bone tissue, tooth loss and can be used in the differential diagnosis of these forms at the disease manifestation stage.
Keywords: TIMP1, aggressive periodontitis, immunohistochemistry, gingival biopsy, prognosis.
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 Kazeko, L. et al. (2019). Biological Markers in Clinical and Experimental Medicine, 3(1), 51-52.
 Kazeko, L. et al. (2019). Biological Markers in Clinical and Experimental Medicine, 3(1), 50-51.
Biography: Kazeko Lyudmila has completed her PhD from Belarusian State Medical University in 1993. She heads the 1st therapeutic dentistry department of Belarusian State Medical University. She has published more than 320 publications in different journals.