O extrato hidroetanólico de Tropaeolum majus L. favorece a cicatrização cutânea em ratos

Abstract

Skin is the largest organ of the humen body. Several cell types, including keratinocytes, Langerhans cells, melanocytes, Merkel cells and fibroblasts indwell in this tissue, ensuring its innumerous functions. Among these functions, the primary barrier against enviromental agressions may be the most import activity. Any damage that determines the interruption of this barrier sets a series of complex physiological responses aiming to restore this essential function in a multiphase process known as wound healing. The inflammatory phase of wound healing is subjected to possible instabilities. This may increase risks of delayed repair due to lytic and oxidative unbalances and continued inflammation. Therefore, the restoration of physiological defenses through the introduction of antioxidant and anti-inflammatory substances may result in an important strategy for recovery. Tropaeolum majus L. is a plant original from the South American Andes with many popular uses recognized by folk medicine for its anti-inflammatory and wound healing properties. Some of these traditional uses have already been scientifically justified. The aim of this work was to evaluate the wound healing potential of T. majus hydroethanolic extract. Fifty-four male Wistar rats were surgically wounded and treated daily with base emulsion (control group), base emulsion plus allantoin 1% (positive control group), or base emulsion plus T. majus dried hydroethanolic (70%) extract. Euthanasia and skin sample removal was carried 3, 7, and 14 days after surgery (day 0). The samples were destined to biochemical and morphological analyses. The extract was submitted to phytochemical characterization to determine major phenolic compounds. Total content of phenolic compounds, total content of flavonoids, and antioxidant capacity were also determined. Allantoin showed the expected results for a wound healing agent. However, T. majus extract demonstrated superior results compared to the positive control. The extract improved oxidative parameters of the wound, reduced inflammation, increased the number of fibroblasts, increased dermal connective tissue organization and collagen deposition. T. majus also offered benefits to re-epithelization. The extract analyses evidenced the presence of two major phenolic compounds, chlorogenic acid and rutin, as well as elevated content of phenolics and flavonoids associated to an elevated antioxidant capacity. It was concluded that T. majus extract presented excellent wound healing activity, probably connected to phenolic substances in its composition, demonstrating the possibility of pharmaceutical applications.