Bioactivities of the ethanol extract from Ageratum fastigiatum branches: antioxidant, antinociceptive and anti-inflammatory.

The present study was designed to investigate the antioxidant, antinociceptive and anti-inflammatory activities of the ethanol extract from Ageratum fastigiatum branches. Phytochemical screening and total phenol and flavonoid contents were determined. The antioxidant activity was assessed by 2,2-diphenyl-1-pycrilhydrazin (DPPH) and iron reducing power methods. The antinociceptive effect was evaluated using the acetic acid-induced writhing, formalin, hot plate and tail immersion assays; while the carrageenan-induced paw edema and pleurisy tests were performed to examine the anti-inflammatory activity against acute inflammation. The extract revealed the presence of flavonoids, tannins, coumarins, terpenes, sterols and saponins. Expressive levels of total phenols and flavonoids and a promising antioxidant effect were quantified. At the doses of 50, 100 and 200 mg/kg, the extract inhibited the writhing, reduced both phases of paw licking time and increased the reaction time on the hot plate. In the tail immersion test, the extract (50, 100 and 200 mg/kg) caused a significant inhibition of pain. In these doses, the paw edema, exudate volume and leucocyte mobilization were significantly reduced. These results suggest that A. fastigiatum can be an active source of substances with antioxidant, antinociceptive and anti-inflammatory activities, adding scientific support to the appropriate use in the Brazilian folk medicine.

Essential oil from Ageratum fastigiatum reduces expression of the pro-inflammatory cytokine tumor necrosis factor-alpha in peripheral blood leukocytes subjected to in vitro stimulation with phorbol myristate acetate

Abstract Ageratum fastigiatum (Gardner) R.M. King & H. Rob., a member of the Asteraceae family popularly known in Brazil as "matapasto", is indicated in folk medicine as anti-inflammatory and analgesic. Despite its popular use, little is known about its potential effect on the parameters involved in an inflammatory response. The objective of this study was to characterize the chemical composition of the essential oil from A. fastigiatum and to evaluate the frequency of tumor necrosis factor alpha and interferon gamma producing cells in peripheral blood lymphocytes stimulated with phorbol myristate acetate in the presence of essential oil from A. fastigiatum. Non-toxic concentrations of essential oil from A. fastigiatum were evaluated in cultures of peripheral blood leucocytes using the trypan blue exclusion assay by flow cytometry. GC–MS analysis revealed that the prevalent compounds identified in the essential oil from A. fastigiatum sample were α-pinene, limonene, trans-caryophyllene, α-humulene, caryophyllene oxide, 1,2-humulene-epoxide, 1,6-humulanodien-3-ol, and α-cadinol. Results showed that exposure to essential oil from A. fastigiatum at concentrations of 0.5 × 10−2 and 1 × 10−2 µl/ml caused no alterations in leukocyte viability as compared to the control group. Both concentrations lowered the percentage of tumor necrosis factor alpha (+)-lymphocytes and neutrophils. There were no changes in the percentage of lymphocytes positive for the interferon gamma cytokine. Our results suggest that part of the anti-inflammatory activity attributed to A. fastigiatum may be due to the effect of some of its components in decreasing the number of cells that produce the pro-inflammatory cytokine tumor necrosis factor alpha.

The effect of Ageratum fastigiatum extract on Rhodnius nasutus, vector of Chagas disease

Control of Chagas disease is based on insecticide spraying in domiciles in order to exterminate triatomine populations. However, since the vectors differ in susceptibility to currently used insecticides, the screening of the toxic potential of Brazilian flora may identify new molecules lethal to triatomines. This study evaluated the toxicity of ethanolic extract of Ageratum fastigiatum (Gardner) R.M. King & H. Rob., Asteraceae, on Rhodnius nasutus, a known vector of Chagas disease. Ethanolic extracts of the aerial parts of A. fastigiatum were prepared at 25 and 50 mg/mL concentrations, and 5 µL was applied to fifth-instar nymphs of R. nasutus (n=30). Controls included nymphs that were treated with 5 µL ethanol (n=30) or left untreated (n=30). The percentage of dead insects in each group was observed at 24, 48, 72, 96 and 120 h after application. The extracts of A. fastigiatum showed a mortality rate of about 37% and 77% after 120 h, at concentrations of 25 and 50 mg/mL, respectively. In control groups, the mortality rate remained under 7%. The extract of A. fastigiatum contains a coumarin, a molecule with recognized toxicity in insects, and which may be responsible for killing the triatomines.

Contribution for the phytochemical studies of Ageratum fastigiatum

Organic extracts from leaves plus branches plus inflorescences of Ageratum fastigiatum (Gardner) R. M. King & H. Rob., Asteraceae, were fractionated through classic chromatography. The steroids stigmasterol, chondrillasterol and campesterol were isolated from hexane extract. The triterpenes lupeol, taraxasterol, α-amyrin, β-amyrin, pseudotaraxasterol, lupeol acetate and α-amyrin acetate were isolated from ethyl acetate extract. Steroids and triterpenes were identified by GC-MS. The coumarin ayapin was isolated from ethanol extract and identified by NMR. Essential oils of the fresh leaves and fresh inflorescences were obtained by hydrodistillation and analyzed for GC-MS. The main components in both essential oils were α-pinene, limonene and germacrene D.

Analgesic and anti-inflammatory properties of essential oil from Ageratum fastigiatum

The chemical composition, analgesic and anti-inflammatory properties of essential oil from Ageratum fastigiatum were investigated. The main compounds found in the essential oil were germacrene D, α-humulene and β-cedrene. The oil, with LD50 of 2.50 g/kg, inhibited the acetic acid-induced writhing at the dose of 200 mg/kg. In the formalin test, the oil inhibited the first phase (200 mg/kg) and the second phase (100 mg/kg and 200 mg/kg). In the hot plate test, after 30 and 60 min of treatment the doses of 100 and 200 mg/kg increased the reaction time. The antiedematogenic effect, reduction on the exudate volume and leukocyte mobilization were observed at the doses of 100 and 200 mg/kg. The results indicated that A. fastigiatum possessed the analgesic and anti-inflammatory properties that supported the popular medicinal use of the plant.

A composição química e as propriedades analgésica e antiinflamatória do óleo essencial de Ageratum fastigiatum foram investigadas. Os principais constituintes do óleo essencial foram germacreno D, α-humuleno e β-cedreno. O óleo, com DL50 de 2,50 g/kg, inibiu as contorções abdominais induzidas por ácido acético na dose de 200 mg/kg. No teste da formalina, o óleo inibiu a primeira fase (200 mg/kg) e a segunda fase (100 e 200 mg/kg). O tempo de latência aumentou no teste da placa quente, após 30 e 60 minutos de tratamento, nas doses de 100 e 200 mg/kg. O efeito antiedematogênico, assim como a redução do volume do exsudato e da migração leucocitária foram observados nas doses de 100 e 200 mg/kg. Os resultados indicam que o A. fastigiatum possui propriedades analgésica e antiinflamatória, o que corrobora com o uso popular da planta.

Caracterização morfoanatômica de Ageratum fastigiatum (Asteraceae) / Morpho-anatomical characterization of Ageratum fastigiatum (Asteraceae)

Ageratum fastigiatum (Gardn.) R. M. King et H. Rob. (Asteraceae), conhecido como "matapasto", é uma planta usada na medicina popular como cicatrizante e antimicrobiano. O objetivo deste trabalho foi realizar caracterização morfoanatômica da folha, dos ramos e da raiz de A. fastigiatum. Secções transversais e paradérmicas, coradas com safranina/azul de astra e azul de toluidina foram analisadas ao microscópio. As folhas são alternas ou fasciculadas; a inflorescência é constituída de capítulos; as flores com corola lilás; ausência de pápus. A raiz apresenta crescimento secundário na zona de ramificação com estruturas secretoras. O caule possui epiderme uniestratificada, estômatos, tricomas tectores simples e tricomas glandulares capitados. O pecíolo exibe contorno côncavo-convexo e a epiderme é unisseriada. A lâmina foliar é anfiestomática e o mesófilo dorsiventral. A epiderme possui células de contorno sinuoso e os estômatos são do tipo anomocítico. Os caracteres morfoanatômicos permitiram estabelecer parâmetros para identificação do A. fastigiatum.

Ageratum fastigiatum (Gardn.) R. M. King et H. Rob. (Asteraceae), known as "matapasto", is a plant used in the popular medicine as cicatrizant and antimicrobial. The aim of this work was to perform a morpho-anatomical characterization of the leaves, the stems and the roots from A. fastigiatum. Transversal and paradermic sections, stained with astra safranin/blue and toluidine blue were analyzed under a microscope. The leaves are alternate or fasciculate; the inflorescence is constituted of chapters; the flowers with lilac corolla; papus is absence. The root presents secondary growth in the ramification area with secretor structures. The stem possesses epidermis unistratified, stomata, simple non-glandular trichomes and capitates glandular trichomes. The petiole exhibits concave-convex outline and the epidermis is uniseriate. The blade leaf is hypostomatic; the mesophyll is dorsiventral. The epidermis possesses cells of sinuous outline and the stomata of the anomocytic type. The morpho-anatomical characters allowed establishing parameters for identification of A. fastigiatum.