Diabetes alters the involvement of myofibroblasts during periodontal wound healing

Objectives: Myofibroblasts constitute a specific cell phenotype involved in connective tissue healing. Diabetes alters the wound healing response. However, it is not clear whether diabetes modifies the involvement of myofibroblasts in periodontal wounds. Materials and Methods: Type I diabetes was induced in rats through streptozotocin injection, and periodontal wounds were performed. Wound healing was evaluated histologically at 2, 5, 7, and 15 days by measuring epithelial migration, neutrophil infiltration, and collagen and biofilm formation. Distribution of myofibroblasts was evaluated through immunofluorescence for α-smooth muscle actin. Data analyses were performed using the Shapiro–Wilk, ANOVA, or Kruskal–Wallis tests. Results: Diabetic wounds were characterized by delayed epithelial closure, increased neutrophil infiltration, biofilm formation, and reduced collagen formation. Quantification of the myofibroblasts showed a significant reduction at 5 and 7 days in wounds of diabetic rats and an increase at 15 days when compared to wounds of non-diabetic rats. Conclusions: Diabetic wound healing was associated with decreased epithelial and connective tissue healing, increased levels of inflammation, and biofilm formation. Myofibroblast differentiation was delayed in diabetic periodontal wounds at early time points. However, myofibroblasts persisted at later time points of healing. The present study suggests that diabetes alters the involvement of myofibroblasts during periodontal wound healing.