Padronização botânica e avaliação da atividade cardiovascular de folhas de Cecropia pachystachya Trécul, URTICACEA

Abstract

Cecropia pachystachya Trécul is popularly known as embaúba, árvore-da-preguiça, pau-de-lixa and ambaí. It is a medicinal species found in Latin America, especially in Brazil and Argentina. Cecropia pachystachya is used in traditional medicine as anti-inflammatory, antitussive, bronchodilator, mucolytic and to treat cardiovascular problems. This medicinal plant is sold fragmented and is often confused with other species of Cecropia and even with species from other botanical families, such as Tetrapanax papyrifer, due to the same popular name and similar morphology. Considering the cardiovascular properties, the common nomenclature and the morphological similarities, the objective was to botanically and chemically analyze the leaves of C. pachystachya, in addition to conducting a pharmacological study, in order to provide anatomical and phytochemical characteristics to assist in the identification and characterization of the plant species , and evaluate the effectiveness and safety of using aqueous extracts obtained from the leaves of this taxon.Usual methods in light and scanning electron microscopy were used for the morphoanatomical description. For pharmacological evaluation, the fraction soluble in ethanol (FSE) originated from the aqueous extract of the leaves of Cecropia pachystachya was chemically characterized by CLAE-DAD-EM and EM/EM and subjected to toxicity studies, acute and prolonged diuresis, hypotensive and antioxidant effects in doses of FSE (30, 100 and 300 mg/kg) in Wistar rats. The main anatomical markers found were hypoestomatic leaf, dorsiventral mesophyll, filariform, conical and pluricellular trichomes, biconvex midrib with disorganized collateral vascular bundles, circular petiole, presence of calcium oxalate crystals, starch grains, lipophilic, lignified and phenolic compounds. The main secondary metabolites found were phenolic acids and flavonoids, such as: quinic acid, hexonic acid, citric acid, 5-O-E-caffeoil quinic acid, procyanidin dimer, C-hexosyl C-pentosyl luteolin, C-hexosyl luteolin, C-hexosyl apigenin, C-hexosyl O-pentosyl apigenin, O-deoxyhexosyl-hexosyl quercetin and O-hexosyl quercetin. FSE did not demonstrate toxic effects at the maximum dose of 2000 mg/kg and showed acute diuretic activity of 8 h at all doses (30, 100 and 300 mg/kg). Vasodilator action was not verified in a study of mesenteric bed and antioxidant effects were identified, mainly to the activity of superoxide dismutase. The results obtained in the morphoanatomical characterization provide subsidies for the identification of C. pachystachya, as well as the differentiation of the other embaúbas. Histochemical and chemical studies have shown the presence of phenolic acids and flavonoids. The pharmacological study showed diuretic and antioxidant activity.