A Role for Non-Antimicrobial Actions of Tetracyclines in Combating Oxidative Stress in Periodontal and Metabolic Diseases: A Literature Review

This review addresses the role of adjunctive tetracycline therapy in the management of periodontal diseases and its efficacy in reducing inflammatory burden, oxidative stress and its sequelae in patients with coexisting features of metabolic syndrome. Removal of the dimethylamine group at C4 of the tetracycline molecule reduces its antibiotic properties, enhancing its non-antimicrobial actions; this strategy has aided the development of several chemically modified tetracyclines such as minocycline and doxycycline, by altering different regions of the molecule for focused action on biological targets. Tetracyclines are effective in reducing inflammation by inhibiting matrix metalloproteinases, preventing excessive angiogenesis, inhibiting apoptosis and stimulating bone formation. There are important applications for tetracyclines in the management of diabetic, dyslipidaemic periodontal patients who smoke. The diverse mechanisms of action of tetracyclines in overcoming oxidative stress and enhancing matrix synthesis are discussed in this review

Nanotechnology in ligature-induced periodontitis: protective effect of a doxycycline gel with nanoparticules

OBJECTIVES: The aim of this study was to test the efficacy of a locally applied 8.5% nanostructured doxycycline (DOX) gel in preventing alveolar bone loss in experimental periodontal disease (EPD) in rats by using the tapping mode atomic force microscopy (AFM). MATERIAL AND METHODS: EPD was induced in 24 Wistar rats. Animals were treated with the doxycycline gel topically, immediately after EPD induction, and 3 times a day during 11 days. Four groups (n=6) were formed as follows: Naïve group (animals not subjected to EPD nor treated); non-treated (NT) group (animals subjected to EPD, but not treated); vehicle gel (VG) group (animals subjected to EPD and treated with topical gel vehicle); and DOX group (test group): animals subjected to EPD and treated with the 8.5% DOX gel. In order to investigate topographical changes in histological sections, a novel simple method was used for sample preparation, by etching sections from paraffin-embedded specimens with xylol. RESULTS: Comparing the AFM images, several grooves were observed on the surface of the alveolar bone and other periodontal structures in the NT and VG groups, with significantly greater depths when compared to the DOX group (p<0.05). CONCLUSIONS: Periodontal structures were brought into high relief confirming to be a simple and cost-effective method for AFM imaging with ultrastructural resolution. The doxycycline gel was able to afford periodontal surface preservation, with flatter grooves