Gingival MMP-1 and HBD-3 mRNA expression elevated in chronic periodontitis, correlating with tissue destruction

Periodontitis, a chronic inflammatory disease, results from dysregulated host-microbe interactions, leading to progressive connective tissue degradation and alveolar bone loss. Current diagnostic methods often rely on clinical parameters, which may not fully capture the underlying molecular pathology or disease activity. Matrix metalloproteinases (MMPs), particularly MMP-1 and MMP-9, are key enzymes involved in extracellular matrix breakdown, while human β-defensin-3 (HBD-3) is an antimicrobial peptide crucial for innate immune defense. Understanding the specific expression patterns of these biomarkers in different stages of periodontal disease could offer novel diagnostic tools and therapeutic targets beyond traditional approaches.

Researchers quantified gingival mRNA expression of MMP-1, MMP-9, and HBD-3 in human gingival biopsies. The study included 23 healthy controls (probing depth [PD] < 3 mm), 18 gingivitis patients, and 19 moderate-to-severe chronic periodontitis patients (PD > 5 mm). RNA was extracted using FavorPrep™ kits, followed by cDNA synthesis. Gene expression was then measured via quantitative real-time PCR (qRT-PCR) and normalized to GAPDH expression. The 2-ΔΔCt method was used for relative quantification, with statistical analysis employing Kruskal-Wallis and Games-Howell post-hoc tests.

Chronic periodontitis patients exhibited significantly elevated MMP-1 expression (31.00 ± 7.1) compared to healthy controls (21.26 ± 4.3; p = 0.001), with overall intergroup differences also highly significant (p = 0.001). HBD-3 expression showed significant variation across all groups (p = 0.045), peaking in the periodontitis group (38.22 ± 9.6), although pairwise comparisons between groups were not statistically significant. MMP-9 expression, however, demonstrated no significant intergroup differences (p = 0.688).