Caracterização e avaliação in vivo de extrato seco de Leonurus sibiricus (L.) no processo de cicatrização

Abstract

Skin wounds are essentially characterized by an injury that leads to discontinuity of the skin structure to varying the extent degrees. The healing process is complex and involves different steps such as hemostasis, inflammation, proliferative phase, and tissue remodeling. Many factors can interfere with cellular and molecular changes during the healing process, and modulation of the inflammatory phase can accelerate this process with fewer ill effects, such as pain, edema, and the presence of exudates.

Leonurus sibiricus is a plant of Asian origin that is popularly used as an anti- inflammatory; however, there are no scientific reports of its application to help skin

healing. Thus, the aim of this study was to characterize the aqueous and methanolic extracts of L. sibiricus and to evaluate healing in an animal model treated with gel containing the extracts. The characterization of the extracts was performed by mass spectroscopy and total flavonoids were quantified. Wound healing was evaluated by lesion retraction and tissue regeneration in histological study stained with hematoxylin- eosin and picrossirius. Several chemical compounds were found in the spectra of the extracts, showing different composition among them, mainly in the mass range of 350 to 550 m/z. However, some compounds such as siringic acid, apigenin, luteolin-7- methyl-ether, chlorogenic acid and luteolin are possibly present in both extracts. The animals treated with the extracts showed greater retraction of the lesions on the fourteenth day after the beginning of the study compared to the control group. The histological study showed better tissue regeneration in the animals treated with the extracts than in the control group, and the animals in the methanolic group showed more organized tissue regeneration with a greater presence of type I collagen from the fourteenth day on. Thus, the extracts present themselves as promising for use as cicatrizing agents, being necessary further studies on the mechanisms of action of the chemical compounds found.