RESUMO
The Nahua of the Mexican state of Veracruz use Baccharis conferta in the treatment of a variety of gastrointestinal illnesses, especially diarrhoea associated with gastrointestinal cramps. The aerial parts of B. conferta were investigated phytochemically and pharmacologically using the guinea pig ileum assay as a model (histamine, KCI and electric stimulation). The crude ethanolic extract showed a dose-dependent antispasmodic effect that was particularly strong in flavonoid-rich fractions (e.g. IC50 value for fraction E.3.1 from the ethyl acetate fraction, in histamine-induced contraction, 10 microg mL(-1)). Several flavonoids (apigenin-4',7-dimethylether, naringenin-4',7-dimethylether, pectolinarigenin and cirsimaritin) were isolated, while others were identified in complex fractions by GC-MS. The flavonoids play an important role in the antispasmodic activity of this indigenous drug. Additionally, oleanolic acid and its methyl ester as well as erythrodiol were isolated. Oleanolic acid methyl ester shows weak antibacterial activity against M. luteusand E. coli (20 microg/spot in a TLC assay). The phytochemical as well as the pharmacological data provide some in-vitro evidence forthe use of B. conferta in thetreatment of gastrointestinal cramps.
Assuntos
Antagonistas dos Receptores Histamínicos/uso terapêutico , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Cloreto de Potássio/antagonistas & inibidores , Animais , Anti-Infecciosos/análise , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Estimulação Elétrica , Cromatografia Gasosa-Espectrometria de Massas , Cobaias , Íleo , México , Testes de Sensibilidade Microbiana , Parassimpatolíticos/análise , Parassimpatolíticos/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificaçãoRESUMO
Five new linear acetylenic compounds, namely, pentadeca-6,8,10-triynoic acid (1), octadeca-8,10,12-triynoic acid (2), trans-pentadec-10-en-6,8-diynoic acid (3), cis-hexadec-11-en-7,9-diynoic acid (4), and cis-octadec-12-en-7,9-diynoic acid (5), were isolated from the bark of Heisteria acuminata by bioassay-guided fractionation, using cyclooxygenase (COX) and 5-lipoxygenase (5-LO) assays as models for antiinflammatory activity. The structures of compounds 1-5 were established by NMR, MS, IR, and Raman spectroscopy. These isolated compounds were found to be potent inhibitors of COX. Compounds 4 and 5 were the most potent inhibitors of 5-LO, whereas the other compounds only showed a weak inhibition at the same concentration.
Assuntos
Acetileno/análogos & derivados , Acetileno/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Epiderme Vegetal/química , Plantas Medicinais/química , Acetileno/farmacologia , Anti-Inflamatórios/farmacologia , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Equador , Inibidores de Lipoxigenase/isolamento & purificação , Inibidores de Lipoxigenase/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , EsteroidesRESUMO
In our ongoing program to find new anti-inflammatory compounds, 58 extracts from 46 different medicinal plant species, used in treatment of inflammatory disorders-38 plants from the traditional medicine of Western Samoa and eight originating from the indigenous medicine of the Shipibo-Conibo tribe of Peruvian Amazonia-ere evaluated. The ability of all extracts to inhibit cyclooxygenase-1 catalysed prostaglandin biosynthesis in vitro was examined. Of the plant species tested 14 showed moderate to strong inhibition; including 11 Samoan and three Peruvian species. Further, 12 Samoan and all eight Peruvian species were investigated on their inhibitory activity of ethyl phenylpropiolate induced rat ear oedema in vivo. Significant activity was shown by 10 of the Samoan and by all eight Peruvian species. An additional evaluation of the most active species was provided through a compilation of existing literature documenting traditional medicinal uses, pharmacological activity and chemical constituents. Several known cyclooxygenase-1 inhibitors were reported to which the observed pharmacological activity can be attributed at least partly. The combination of chemical and pharmacological literature data and our experimental data may help to explain the anti-inflammatory use of these species in indigenous medicine.