Avaliação da atividade cicatrizante in vitro e in vivo do extrato hidroalcoólico de Laguncularia racemosa (L) C.F. Gaertn

The wound is defined as the separation of the tissues from the body or any tissue injury to the detriment of its basic functions. The search for drugs that accelerate the healing process has become relevant, since countless people suffer from surgical or traumatic wounds each year. Several authors investigate medications that can accelerate the healing of wounds, reduce painful symptoms and present a great cost-benefit ratio; among them, the extracts of endemic species of the Pernambuco mangroves, such as Laguncularia racemosa (L.), showed cicatrizant activity due to high levels of secondary metabolites, such as tannins. Therefore, the objective of this work was to evaluate the healing activity in vitro and in vivo of the hydroalcoholic extract and the semi-solid preparation of L. racemosa leaves. The collection of the vegetal material was carried out in the Itamaracá mangrove, located in the north coast of Pernambucano. After obtaining the extract the phytochemical profile, the antioxidant activity and the dosage of the total phenols, tannins, flavonoids and coumarins were evaluated in order to determine and quantify the secondary metabolites. The in vitro tests were performed by the evaluation of cytotoxicity and the cicatrization test with the strains L929, HaCat and VERO. For the evaluation of the healing activity in vivo a semi-solid formulation of the hydroalcoholic extract of the leaves of L. racemosa was prepared at 5 and 10% and tested in the excision model for a period of 3, 7, 14 and 21 days. The phytochemical profile of the extract indicated the presence of total phenols, tannins, flavonoids and coumarins and quantitatively presented total phenol content and tannins of 128.24 ± 2.6 and 113 ± 0.43 mg EAT / g, respectively, of flavonoids 85 , 75 ± 7.19 mg ER / g and coumarins 226.36 ± 8.7 mgEC / g. The extract presented a moderate antioxidant activity and showed no significant cytotoxicity against the strains L929, VERO and HaCat in the period of 72h incubation at concentrations ranging from 1.56 to 200 μg / mL. In vitro healing, the hydroalcoholic extract at 50 μg / mL induced significant cell migration (p <0.05) in all strains evaluated, when compared to the control. In the healing activity in vivo, the groups treated with the hydroalcoholic extract of L. racemosa at 5 and 10% showed a significant contraction degree in the period of 3 days, with a percentage of 23.45% ± 3.4 and 23.46% ± 2.8, respectively, compared to the control of 5, 95% ± 0.5. After 7 days, the degree of contraction was 77.35 ± 3.0 and 76.10 ± 6.3 for concentrations of 5 and 10%, respectively, compared to the control of 58.24 ± 5, 0. In the histopathological analyzes, groups treated at 5 and 10% promoted better tissue re-epithelization with massive presence of fibroblasts, vessel formation, collagen fibers and keratin, characterizing a faster evolution of the cicatricial process compared to the other treatments. The study showed that the topical administration of the formulations containing hydroalcoholic extract of the dry leaves of L. racemosa helps accelerate the healing process, showing therapeutic potential on the cutaneous lesions.