Phytochemical screening of the dichloromethane–ethanolic extract of Eriosema campestre var. macrophylum roots and its antiproliferative effect on human peripheral blood lymphocytes

ABSTRACT Eriosema campestre var. macrophylum (Grear) Fortunato, Fabaceae, is a native plant of the Brazilian Cerrado and the decoction of its roots has been used by folk medicine for the therapy of inflammatory diseases. In this study we aimed to investigate the effect of the dichloromethane–ethanolic extract of E. campestre roots on the proliferative response of lymphocytes and to examine the profile of IL-2 production. The effect of dichloromethane–ethanolic extract of E. campestre on the proliferation of phytohemagglutinin-stimulated lymphocytes was evaluated by using flow cytometry and the cell supernatants were assayed for IL-2 concentrations by using an enzyme-linked immunosorbent assay. The phytochemical screening of E. campestre roots was performed to determine the main secondary metabolites through chromogenic and precipitation reactions and by using HPLC-PAD. In addition to the presence of subclasses of flavonoids (flavones and flavonols) in dichloromethane–ethanolic extract of E. campestre, we observed that the extract induced a concentration-dependent decrease in IL-2 levels on the supernatant of the cell cultures as well as an antiproliferative effect on T lymphocytes, including CD4+ and CD8+ cells. The anti-inflammatory effects attributed to E. campestre by folk medicine may partly be explained by its antiproliferative action on T lymphocytes.

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.

Traditional uses of American plant species from the 1st edition of Brazilian Official Pharmacopoeia / Usos tradicionais das plantas americanas presentes na 1ª Edição da Farmacopéia Brasileira

The first edition of the Brazilian Official Pharmacopoeia (FBRAS), published in 1929, is a rich source of information about American medicinal plants, since it lists species used in both traditional and conventional medicine. In this study, we have performed a survey of the traditional uses of plants described in eighty-seven Monographs from the FBRAS in twenty bibliographies written from the 19th century to the 1970s. Eighty-six different traditional uses are described in three or more books; some of them were cited in ten or more books, illustrating their widespread use and importance in medicine. The species from the first edition of the FBRAS have a long tradition of medical utility, which is confirmed by historical records. In surveying these medically relevant species, we hope to encourage policy makers and the scientific public as a whole to engage in a strong debate in an attempt to improve and facilitate the pharmacological study of these species.

A 1ª Edição da Farmacopéia Brasileira, publicada em 1929, é uma rica fonte de informação sobre as plantas medicinais nativas das Américas, uma vez que ela lista as espécies usadas na medicina tradicional e oficial da época. Neste estudo, foi feita uma extensa revisão sobre os usos tradicionais de plantas descritas em oitenta e sete Monografias presentes na FBRAS 1ª Edição, em vinte livros publicados do século 19 até a década de 1970. Oitenta e seis diferentes usos medicinais foram citados e três ou mais livros; mesmos usos foram descritos em dez ou mais referências, mostrando seu amplo emprego e importância como medicamento. Os resultados mostram que as espécies nativas presentes na 1ª Edição da FBRAS têm longa tradição em uso, confirmado pelos dados históricos. É necessário, portanto, que estudos farmacológicos com essas plantas sejam estimulados, como forma de promover seu melhor aproveitamento.