Hypoxia and collagen crosslinking in the healthy and affected sites of periodontitis patients

Present study suggests that diseased sites of periodontitis with stage 3 grade B and C had decreased fibroblast cell density, hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF) expressions while increased inflammatory cell counts compared to both healthy sites of the periodontitis patients and healthy controls. Collagen maturation enzymes also decreased in the diseased sites. Objective: The present study aimed at determining markers of hypoxia and collagen crosslinking in healthy and diseased gingiva from healthy individuals and periodontitis patients. Methods: Group-1; healthy individuals, Group-2; healthy sites of periodontitis patients-stage 3 grade B, (H-GradeB) Group-3; diseased sites of periodontitis patients-stage 3 grade B, (D-GradeB). Group-4; healthy sites of periodontitis patients-stage 3 grade C, (H-GradeC). Group-5; diseased sites of periodontitis patients-stage 3 grade C, (D-GradeC). Plaque index (PI), gingival index (GI) and clinical attachment levels (CALs) were recorded. Gingival biopsies were obtained. Fibroblast and inflammatory cells were counted. HIF-1α, prolyl hydroxylase (PH), VEGF, lysyl oxidase (LOX) and lysyl hydroxylase (LH) levels were determined via immunohistochemistry. Results: Fibroblast cell counts were lower in D-GradeC and D-GradeB than other groups. C group had highest fibroblast cell counts. Inflammatory cell counts were highest in the D-GradeC and lowest in C group. HIF-1α levels were highest in C group and decreased in diseased sites. Lowest value was observed in D-GradeC group. VEGF, PH, and LH levels were higher in the control group compared to other groups. LOX levels were similar in the groups except for D-GradeC. LOX levels were similar in the groups except for D-GradeC which is significantly lower than those of the control group and healthy sites. Conclusions: The results revealed that diseased sites of periodontitis patients had decreased fibroblast cells, HIF and VEGF expressions while increased inflammatory cells. Collagen crosslinking tend to decrease with disease regardless of stage and grade of disease.