Hydroalcoholic extract of Adansonia digitatas trunk bark, in topical application, possess in vivo wound healing and in vitro anti-inflammatory and antioxidant activities

Abstract

Adansonia digitata is a tree plant used in west African local pharmacopoeia. This work aimed to evaluate the wound healing properties of its trunk bark’s hydroethanolic extract in wistar rats. The model of excision wound was used. Wistar rats were treated post-excision topically with neutral carbopol gel (Control), carbopol gels containing 2.5 and 5% of A. digitata hydroethanolic trunk bark extract (ADHE) and L-Mesitran. Pictures were taken post excision for analysis. Biopsies were realized for histological examination of the skin excised and for hydroxyproline determination. In vitro membrane stabilization anti-inflammatory test, DPPH and FRAP antioxidant tests, and phytochemical tests were performed. The results show a better rate of contraction in ADHE 2.5 and 5% animals (+56 ± 0.52% and +68 ± 0.24% respectively) as earlier as on day three post-excision. The hydroxyproline assay confirmed a better collagen production in ADHE 2.5% and 5% animals (+102.5 ± 2.9%, and +107 ± 3.0% respectively). Histological analysis showed a rapid re-epithelialization in ADHE animals. The anti-inflammatory test indicated an IC50 of 16.521 ± 0.525 µg/mL, very close to Aspirin (16.826 ± 0.341 µg/mL), showing a possible anti-inflammatory activity of ADHE. The extract reduced DPPH radical (IC50 of 344.985 ± 17.139 µg/mL) and ferric ions (EC50 = 178.689 ± 0.250 µg/mL). Phytochemical investigations revealed the presence of alkaloids, terpenoids, and polyphenolic compounds. Flavonoids in particular, with an amount of 51.694 ± 0.174 mgER/g, should explain the wound healing activity observed, making the hydroethanolic extract of A. digitata a potential remedy for excision wounds.