Accelerative effect of SOO on infected wound healing; (A) by inhibition in bacteria colonization and growth, (B) by up-regulating the expression of IL-1β, IL-6 and TNF-α as pro-inflammatory cytokines and modulating tissue inflammation. (C) by raising the TAC level and reduced MDA content. (D) by up-regulating the VEGF and FGF-2 expression improves the angiogenesis and fibroblasts migrating, respectively. All these alterations resulted in improved collagen biosynthesis and re-epithelialization.

Salvia officinalis L. (Lamiaceae) is known to have antibacterial properties possibly conducive to the healing process of infected wounds.

The present study aimed to evaluate the effects of an ointment containing Salvia officinalis essential oil (SOO) on an infected wound model.

Essential oil hydrodistillated from the dried leaves of the plant was analyzed by GC-FID and GC–MS. After creating two full-thickness cutaneous wounds, mice were classified into four groups, control, and animals treated with 2 % mupirocin® (standard positive drug), and 2 % and 4 % (w/w) of SOO. In order to evaluate the effects of SOO on the wound healing phases, the expression levels of interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), cyclin-D1, Bcl-2, fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factors (VEGF) were analyzed using qRT-PCR. Immunohistochemistry analysis, tissue total antioxidant capacity (TAC) and malondialdehyde (MDA) were further assessed in all groups.

Concerning essential oil, the main compounds were found to be cis-thujone (26.8 %), camphor (16.4 %), trans-thujone (14.1 %) and 1,8-cineole (10.8 %). Our findings showed that the topical application of SOO was able to shorten the inflammatory phase and accelerate the cellular proliferation, re-vascularization, collagen deposition and re-epithelialization in comparison to the control group (p < 0.05). Moreover, increased mRNA levels of FGF-2 and VEGF, and up-regulation of cyclin-D1 and Bcl-2 were observed following the topical application of SOO compared to the control group (p < 0.05). The expression levels of IL-6, IL-1β and TNF-α were reduced in animals treated with SOO on days 3, 7 and 14 (p < 0.05).

Administration of SOO increased the TAC level and reduced the MDA content and levels of IL-1β and TNF-α. It is concluded that SOO is able to accelerate the wound healing process by regulating the expression of pro-inflammatory cytokines, growth factors, and antioxidant properties.