Fração acetato de mansoa hirsuta: análise toxicológica, farmacológica, química e desenvolvimento de filme polimérico como curativo para cicatrização de feridas

Abstract

Mansoa hirsuta D.C. (Bignoniaceae), popularly known as cipó-de-alho, is a native species from the Brazilian semiarid region and is traditionally used in the treatment of sore throats and diabetes. Studies report that extracts and fractions of this species have several pharmacological actions such as antifungal and antioxidant activities, endothelium-dependent vasodilator effect, and inhibition of the angiotensin-converting enzyme, nitric oxide production, and lymphocyte proliferation. In this scenario, this study followed research lines: (1) investigating the composition, toxicity, anti-inflammatory and analgesic actions, and chemical of the fraction obtained from M. Hirsuta leaves (MHF); and (2) developing chitosan films incorporated with MHF as an innovative formulation for treating wounds. In vitro cell viability was evaluated in 3T3 cells using the MTT assay. At 24, 48, and 72 h, MHF did not show damage to cell viability. For the acute toxicity assay, a single dose of the fraction was administered orally in male and female mice, with no mortality or signs of toxicity. Additionally, in the subchronic toxicity test, no relevant toxicological changes were observed. The results of the open field and rota-rod tests showed that MHF did not alter the locomotor activity and behavior of the mice, nor did it alter the motor coordination and balance of the treated animals. In evaluating the anti-inflammatory activity, single oral administration of MHF significantly reduced carrageenan-induced edema and levels of myeloperoxidase. Furthermore, it has decreased the migration of leukocytes and proteins in the air pouch model. Regarding the antinociceptive activity, it was observed that the highest doses reduced abdominal contortion in response to the administration of acetic acid and significantly inhibited the second phase of the formalin test. Ultra-performance liquid chromatography coupled with a time-of-flight analyzer and mass spectrometry indicated that this fraction is rich in acid triterpenes that can be derived from oleanolic and ursolic acids. Then, films were prepared using the solvent evaporation method and characterized by Fouriertransform infrared spectroscopy, X-ray diffraction, thermogravimetry, differential scanning calorimetry, scanning electron microscopy, and atomic force microscopy. In addition, tensile strength, elongation at break, and thickness were also measured. Chitosan films containing MHF (CMHF) exhibited characteristic bands of chitosan and MHF, revealing a physical mixture of both. CMHF showed amorphous nature, thermostability, and MHF dispersion in the chitosan matrix, resulting in a rough structure. Incorporation of the fraction into the chitosan matrix significantly improved the mechanical performance and thickness of the films. Treatment of wounds in vivo with CMHF for seven days showed a characteristic area of advanced healing, re-epithelialization, cell proliferation, and collagen formation. Furthermore, wound closure reached 100% contraction after ten days of treatment with modulation of interleukins. Therefore, the results of this study indicated that MHF is rich in acid triterpenes and an anti-inflammatory and analgesic potential without causing acute or subchronic toxic effects, and could be a promising source to be explored. Furthermore, the incorporation of the M. hirsuta fraction in chitosan films was advantageous and showed great potential to stimulate healing and regeneration of wounds.