Preliminary Evaluation of Wound Healing Potential of Leonurus japonicus Houtt. Extracts

Leonurus japonicus Houtt. is a medicinal plant popular in Brazil as "rubim", used in local folk medicine for several applications as an anti-inflammatory, antioxidant, analgesic, and antimicrobial phytomedicine. The traditional use for wound healing is related; however, few studies have evaluated the wound healing activity. Thus, this study aimed to analyse the popular indication of the hydroalcoholic and aqueous extracts of L. japonicus aerial parts in a rat wound healing model. The initial chemical characterization was performed using flavonoid quantification and complemented with mass spectroscopy/chemometrics analysis. The wound's lesion contraction and tissue regeneration (histological study stained with hematoxylin-eosin and picrosirius) were determined. Hydroalcoholic and aqueous extracts presented high flavonoid content, and mass spectrometry analysis of the extracts demonstrated the presence of compounds with a mass between 100-650, reinforcing the presence of polyphenolic constituents. The extracts of L. japonicus improve various wound healing phases, like inflammatory modulation, wound contraction, and collagen synthesis, resulting in faster healing in rats. These effects could be related to the extracts' polyphenolic compounds.