Bulbine natalensis and Bulbine frutescens promote cutaneous wound healing

The gel from the leaves of Bulbine natalensis (BN) and Bulbine frutescens (BF) is commonly used as a traditional medicine in South Africa for the treatment of skin wounds and burns. Treatment with both leaf gel extracts has previously been demonstrated to increase tensile strength and protein and DNA content in pig dermal wounds. This study examined the effect of the leaf gel extracts in vivo on histology of wound healing in pigs to elucidate the mechanism of increased tensile strength.

Mirror imaged wounds on the dorsum of 12 post weaning female pigs were treated with either BN or BF, biopsied at days 2, 4, 7, 10 and 16 post-wounding and fixed. Sections of wound tissue were then stained with haematoxylin and eosin and Mallory's stain to analyse the general morphology and collagen arrangement; and smooth muscle actin, vascular endothelial growth factor (VEGF) and transforming growth factor β (TGFβ) receptors were immunolocalised.

Histological analysis of the wound tissue in the study indicated earlier wound contraction and collagen deposition in both treatment groups with re-organisation of the collagen (indicating collagen maturation) evident as early as at day 10.

The results of this study suggests that the leaf extracts increase tensile strength by increasing fibroplasia, differentiation of fibroblasts into myofibroblasts, and increased collagen deposition and maturation. This study further validates the use of the Bulbine leaf gels for the treatment of skin wounds.