AIM OF THE STUDY: However, so far there is no literature available on the anti-inflammatory activity of this species. Henceforth, based on the above background and our previous laboratory findings, we hypothesize that phytoconstituents of A. elliptica could possess anti-inflammatory potential against inflammatory mediators including prostaglandin-E2 (PGE2), cyclooxegenase-2 (COX-2) and cytokines (IL-1β and IL-6).
MATERIALS AND METHODS: Vacuum and column chromatography techniques were employed for the isolation of phytoconstituents. The structure elucidation was carried out using HRESI-MS, 1H and 13C-NMR analysis and compared with the published literature. For cytotoxicity analysis, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed on peripheral blood mononuclear cells. In-vitro anti-inflammatory activities were evaluated against the levels of PGE2, COX-2, IL-1β and IL-6 in lipopolysaccharide (LPS)-induced human plasma using enzyme-linked immunosorbent assay and radioimmunoassay.
RESULTS: Unprecedentedly, chromatographic purification of methanolic leaves extract afforded five flavones namely vitexin, isovitexin, orientin, isoorientin, schaftoside with three flavanols; kaempferol, myricetin and rutin from A elliptica. In cell viability analysis, isolates did not present cytotoxicity up to 50 μM. In anti-inflammatory evaluation, orientin and isoorientin exhibited strong (≥70%), while isovitexin and vitexin produced strong to moderate (50-69%) PGE2, COX-2, IL-1β and IL-6 inhibition at 25 and 50 μM. Isoorientin, orientin, isovitexin, and vitexin showed significant (p
Materials and Methods: Dried root of P. glabra was extracted under reflux with methyl alcohol, fractionated through the vacuum liquid chromatography technique, and evaporated and then purified the compounds using column chromatography and preparative thin-layer chromatography. THP-1 cells were treated with amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol with various concentrations (0-30 µg/mL) and then incubated with MTS reagent for 2h. Treatment was done for 24, 48, and 72h. Then, effects of these compounds were also tested on PGE2, TNF-α, and IL-6 expression in human THP-1-derived macrophage cells for 24h.
Results: Three new compounds such as amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol were isolated. After 24h of incubation, a significant decrease in cell viability was reported with IC50 values of amentoflavone, 5,7,4'- hydroxyflavonoid, and stigmasterol (21 µg/mL ≡ 38 M), (18 µg/mL ≡ 66 M) and (20 µg/mL ≡ 48.5 M), respectively. Whereas for 48 and 72h treatment showed a less decreased cell viability compared with 24h treatment. These compounds also showed a significant reduction in the production of TNF-α, IL-6, and PGE2 in a dose-dependent manner.
Conclusions: The isolated new compounds showed significant cytotoxicity and anti-inflammatory effects.