Wound Healing Effect of Acokanthera schimperi Schweinf (Apocynaceae) Methanol Leaf Extract Ointment in Mice and Its in-vitro Antioxidant Activity.

Background: Acokanthera schimperi is traditionally used for the treatment of wounds and various bacterial infections. Due to the ongoing escalation of antimicrobial resistance, there is an increasing demand for the appropriate wound care and hence, the present study was initiated to investigate the wound healing effects of the leaf extract ointments of A. schimperi in mice and its in-vitro antioxidant activity.

Methods: The crude extract was prepared as 5% and 10% w/w ointments for topical use in mice. Wound contraction and epithelialization period were determined in excision and infected models, whereas tensile strength was determined in an incision model. Besides, its antioxidant activity was evaluated using the DPPH method.

Results: In this study, the 10% w/w extract ointment did not cause toxicity at the 2000 mg/kg limit dose. In the excision model, the 10% w/w ointment exhibited a significant wound contraction effect starting from day 6 to 14 with a complete epithelization shown on day 13. Besides, the 5%w/w ointment showed a significant wound contraction effect starting from day 6 onwards, and a significant decrease in the epithelization period observed on day 16. Conversely, both the 10% w/w and 5% w/w ointments showed significant wound contraction effects starting from day 4 and onwards in the infected model. However, a complete epithelization period was observed on days 14 and 18 in the 10%w/w and 5% w/w/extract ointment treated groups, respectively. In the incision model, the 10% (w/w) and 5% (w/w) extract ointments showed a significant increase in tensile strength by 36.80 and 32.23%, respectively. Moreover, the antioxidant activity of the extract was concentration-dependent with an IC50 value of 5.49± 0.38 µg/µL.

Conclusion: The potential wound healing effects of this plant may provide a candidate source in the discovery of new drugs for the treatment of wounds.