Healing activity of a muco-adhesive formula of Teucrium polium against acetic acid-induced oral ulcer in rats

Abstract

Oral ulcers are highly common painful conditions that harmfully affect the quality of life and require long-term therapy. Muco-adhesive preparations provide efficient and convenient delivery systems that prolong the drug retention time necessary for the different stages of ulcer healing. Therefore, the study aimed to evaluate the healing activity of Teucrium polium in a muco-adhesive formula against acetic acid-induced oral ulcers in rats. Acetic acid was applied to the inner cheeks of the rats and the muco-adhesive formula was applied once daily for 14 days. Acetic acid was found to disrupt the oral tissue histological features, increase collagen deposition, induce oxidative stress through increasing malondialdehyde (MDA) levels and decreasing superoxide dismutase and catalase activities, increase the expression of the inflammatory biomarkers, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), and decreased hydroxyproline content and the expression of the factors that contribute in wound healing including transforming growth factor-beta1 (TGF-β1), vascular endothelial growth factor receptor 1 (VEGFR1), and platelet-derived growth factor receptor beta (PDGFRβ). However, the daily application of a mucoadhesive formula impregnated with T. polium, significantly restored the regular histological features of the oral tissue, decreased the concentration of MDA, TNF-α, IL-6, and COX-2, increased superoxide dismutase and catalase activities, and restored the expression of TGF-β1, VEGFR1, and PDGFRβ. Therefore, T. polium extract muco-adhesive formula can be considered a potential therapy for chronic oral ulcers.