ABSTRACT
ABSTRACT Pharmacological activities as anti-inflammatory, anti-hyperuricemic, anti-gouty arthritis, antitumor and trypanocidal activities of the aerial parts from Lychnophora trichocarpha (Spreng.) Spreng. ex Sch.Bip., Asteraceae (Brazilian arnica) have already been proved. Eremantholide C is a sesquiterpene lactone and one of the active chemical constituents responsible for these activities presented by L. trichocarpha. Therefore, the aim of this work was to develop and validate a stability indicating HPLC method for eremantholide C. Eremantholide C stability was evaluated in L. trichocarpha ethanolic extract and in its isolated form. Analytical conditions employed C18 column, acetonitrile/water in gradient elution, flow of 0.8 ml/min at 30 ºC. To correct for the loss of analyte during sample preparation the use of coumarin as an internal standard was necessary. The developed method provides good separation and resolution of the peaks, allowing quantification of eremantholide C, isolated or directly in the ethanolic extract, in internal standard presence. Validation results showed that this method is linear in the concentration range 2-180 µg/ml, precise, accurate and specific. Stability studies showed that L. trichocarpha ethanolic extract and eremantholide C remain stable for 6 months when stored at room temperature and impermeable glass bottle, therefore they can be used safely and effectively within this period. While at 40 ºC there was stability loss, at 8 ºC a stability increase was observed for the extract and the isolated eremantholide C. Forced degradation studies showed that eremantholide C degraded under acidic and alkaline conditions and was stable for three days under neutral and oxidative conditions, and when exposed to high temperature. Thus, with the development of a stability indicative method and the application of it in eremantholide C stability studies, the results can guide the development of new products that adequately preserve the original features of the biologically active substance with quality, safety and efficacy.
ABSTRACT
Stryphnodendron species, popularly named "barbatimão," are traditionally used in Brazil as anti-inflammatory agents. This study aimed to investigate the effect of barbatimão and 11 other species on the production of tumor necrosis factor-alpha (TNF-α) in lipopolysaccharide- (LPS-) stimulated THP-1 cells, as well as their anti-arthritis activity. The extracts of Stryphnodendron adstringens, Stryphnodendron obovatum, Campomanesia lineatifolia, and Terminalia glabrescens promoted a concentration-dependent inhibition of TNF-α. Mice injected with LPS in the knee joint were treated per os with fractions from the selected extracts. Both the organic (SAO) and the aqueous (SAA) fractions of S. adstringens promoted a dose-dependent reduction of leukocyte migration and neutrophil accumulation into the joint, but none of them reduced CXCL1 concentration in the periarticular tissue. In contrast, treatment with C. lineatifolia and T. glabrescens fractions did not ameliorate the inflammatory parameters. Analyses of SAO by Ultra Performance Liquid Chromatography (UPLC) coupled to electrospray ionization mass spectrometry (ESI-MS) led to the identification of gallic acid along with 11 prodelphinidins, characterized as monomers and dimers of the B-type. Our findings contribute to some extent to corroborating the traditional use of S. adstringens as an anti-inflammatory agent. This activity is probably related to a decrease of leukocyte migration into the inflammatory site. Polyphenols like gallic acid and prodelphinidins, identified in the active fraction, may contribute to the observed activity.
ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Stryphnodendron obovatum Benth. is a Brazilian tree used to treat skin ulceration, promote wound healing, and inhibit the growth of protozoa, including Trypanosoma and Leishmania species. Bioguided fractionation of the ethanol extract of S. obovatum stem bark was performed, and antileishmanial and antioxidant activities of the standardized fractions were analyzed. MATERIALS AND METHODS: Stationary-phase Leishmania amazonensis promastigotes, murine macrophages, and human red blood cells (RBCs) were exposed to plant extract, standardized fractions or isolated compounds for 48 h at 37 °C to evaluate their antiparasitic activity and cytotoxicity. The 2,2-diphenyl-1-picryl-hidrazyl assay was used to evaluate antioxidant activity. RESULTS: The S. obovatum extract and fractions showed antileishmanial and antioxidant activity; however, the organic fraction (OF) showed the best efficacy. We identified gallic acid, gallocatechin, epigallocatechin, catechin, and epigallocatechin gallate in the OF fraction. These compounds effectively inhibited L. amazonensis activity, with gallic acid, gallocatechin, and epigallocatechin gallate showing the highest selectivity. Furthermore, the evaluated compounds had no significant effect on murine macrophages and human RBCs. CONCLUSIONS: The compounds present in the S. obovatum plant bark ethanol extract may provide an alternative therapeutic approach for L. amazonensis treatment.
