Figure 1.

Enzymes biomarkers in periodontitis. (A) The periodontal bacteria. Inflammatory immune responses are all common risk factors for periodontitis. Enzymes associated with periodontal disease reveal the progression of periodontitis. (B) Oral microbial proteases. Gingipain secreted by Porphyromonas gingivalis, including arginine protease (Rgp) and lysine gingipain (Kgp), serve as virulence factors, hydrolyzing host proteins, increasing bleeding tendency, activating inflammation, and causing alveolar bone loss. The dipeptidyl peptidase (DPP) orthologs are specifically distributed in anaerobic oral rods. DPP activities in dental plaque are potent biomarkers indicating the presence of periodontopathic bacteria and disease activity. (C) Oxidative stress-related enzymes. Periodontitis is intricately linked with oxidative-reductive imbalance and oxidative stress. Evidence suggests that patients with periodontitis exhibit elevated levels of oxidative stress markers and reduced levels of antioxidants in their serum or saliva. The activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, or non-phagocytic cell oxidase (NOX) enzyme complexes, increases in patients with periodontal disease. Enzymatic antioxidants associated with periodontitis include catalase, glutathione reductase (GR), and total antioxidant capacity (TAOC). (D) Proteolytic enzymes. The levels of matrix metalloproteinases (MMPs), neutrophil elastase (NE), and myeloperoxidase (MPO) increase in periodontitis, suggesting these enzymes as potential markers of periodontal inflammation.