Beneficial effect of Ageratum conyzoides Linn (Asteraceae) upon inflammatory response induced by carrageenan into the mice pleural cavity.

ETHNOPHARMACOLOGICAL RELEVANCE: Ageratum conyzoides Linn (Asteraceae), a tropical plant that is very common in West Africa and some parts of Asia and South America, has been used to treat inflammatory disorders. In Brazil, teas made from A. conyzoides L. are used as anti-inflammatory, analgesic and anti-diarrheic agents. Therefore, it is necessary to study the mechanism of anti-inflammatory action of A. conyzoides L. to support its medicinal use for treating inflammatory conditions. These studies will also support the development of effective pharmacological agents with potent anti-inflammatory properties. AIM OF THE STUDY: To evaluate the anti-inflammatory effects of the crude extract (CE), its derived fractions: ethanol (EtOH-F), hexane (HEX-F), ethyl acetate (EtOAc-F) and dichloromethane (DCM-F) and isolated compounds, such as 5'-methoxy nobiletin (MeONOB), 1,2-benzopyrone and eupalestin, which are obtained from the aerial parts of A. conyzoides L. MATERIALS AND METHODS: These evaluations were performed using an animal model of inflammation induced by carrageenan. The following inflammatory parameters were analysed: leukocyte influx, protein concentration of the exudate, myeloperoxidase (MPO), adenosine deaminase (ADA) and nitric oxide metabolites (NOx) concentrations, interleukin 10 (IL-10), interleukin 17A (IL-17A), interleukin 6 (IL-6), tumor necrosis factor (TNF), interferon gamma (IFN-γ) and phosphorylation of p65 subunit of NF-κB (p-p65 NF-κB), p38 mitogen-activated protein kinases (p-p38 MAPK) were also analysed. RESULTS: CE, its EtOH-F, HEX-F, EtOAc-F and DCM-F and the isolated compounds, including MeONOB, 1,2-benzopyrone and eupalestin, significantly reduced leukocyte influx, protein concentration of the exudate, MPO, ADA, and NOx concentrations (p<0.05). CE, EtOH-F and isolated compounds significantly reduced IL-17A, IL-6, TNF and IFN-γ levels (p<0.05). CE, EtOH-F and isolated compound 1,2-benzopyrone also increased IL-10 levels (p<0.05). Isolated compounds, MeONOB, 1,2-benzopyrone and eupalestin, reduced p-p65 NF-κB and p-p38 MAPK (p<0.01). CONCLUSIONS: This study demonstrates that A. conyzoides L. exerts its important anti-inflammatory properties by inhibiting leukocyte influx and protein concentration of the exudate, as well as reducing the levels of several pro-inflammatory mediators. The anti-inflammatory action of A. conyzoides L. may be because of the inhibition of p65 NF-κB and MAPK activation by the isolated compounds.

Phytochemical analysis of Vernonanthura tweedieana and a validated UPLC-PDA method for the quantification of eriodictyol

AbstractVernonanthura tweedieana (Baker) H. Rob., Asteraceae, is used in the Brazilian folk medicine for the treatment of respiratory diseases. In this work the phytochemical investigation of its ethanol extracts as well as the development and validation of an UPLC-PDA method for the quantification of the eriodictyol from the leaves were performed. The phytochemical study for this species lead to the identification of ethyl caffeate, naringenin and chrysoeriol in mixture, eriodictyol from leaves, and the mixture of 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-propan-1-one and evofolin B, apigenin, the mixture of caffeic and protocatechuic acid and luteolin from stems with roots, being reported for the first time for V. tweedieana, except for eriodictyol. The structural elucidation of all isolated compounds was achieved by 1H and 2D NMR spectroscopy, and in comparison with published data. An UPLC-PDA method for quantification of the eriodictyol in leaves of V. tweedieana was developed and validated for specificity, linearity, precision (repeatability and intermediate precision), limit of detection (LOD) and limit of quantification (LOQ), accuracy and robustness. In this study, an excellent linearity was obtained (r2 = 0.9999), good precision (repeatability RSD = 2% and intermediate precision RSD = 8%) and accuracy (average recovery from 98.6% to 99.7%). The content of eriodictyol in the extract of leaves of V. tweedieana was 41.40 ± 0.13 mg/g. Thus, this study allowed the optimization of a simple, fast and validated UPLC-PDA method which can be used to support the quality assessment of this herbal material.