Plantain (Plantago L.) species as modulators of prostaglandin E2 and thromboxane A2 production in inflammation.

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE Worldwide distributed plantains (genus Plantago L.) are extensively used in the traditional, but some of them are also accepted in the modern medicine. Wide range of usages is mainly connected to the inflammation processes. AIM OF THE STUDY To support usage of renowned P. lanceolata L. and P. major L., underinvestigated P. altissima L., P. argentea Chaix, P. holosteum Scop. and P. media L. methanol extracts, and their typical constituents (aucubin, apigenin, apigenin-7-O-glucoside, luteolin, luteolin-7-O-glucoside, chlorogenic and ursolic acid) in treatment of inflammation disorders, we conducted study on plantain potential to inhibit production of inflammatory mediators, prostaglandin E2 (PGE2) and thromboxane A2 (TXA2). MATERIALS AND METHODS: LPS-stimulated monocytes (U937 cell line) were used as a model-system to examine anti-inflammatory potential of plantains and their constituents. Produced PGE2 and TXA2 were quantified by LC-MS/MS; qPCR was applied to examine related gene (PLA2, COX-1, COX-2, mPGES-1, mPGES-2, cPGES, TXAS) expression; LC-MS/MS and LC-UV/VIS techniques to analyze extracts composition. RESULTS: In general, examined plantain extracts showed comparable inhibition activity of PGE2 and TXA2 production as aspirin at low-dose concentration. Underinvestigated P. altissima can be pointed out, since it exerted the strongest effect on both PGE2 production and related gene expression. Notable suppression of TXA2 production by P. lanceolata and P. major was observed. But, PCA analysis showed no obvious grouping, implicating that different mechanisms of action are responsible for each sample activity. In most cases, positive correlation was found between content of apigenin and ursolic acid and extracts suppression of PGE2 and TXA2 production and related genes expression. CONCLUSIONS: P. altissima can be regarded as promising anti-inflammatory agent, while novel aspect of P. lanceolata and P. major application (anti-aggregation) can be suggested. P. argentea and P. media could be considered as a good source of ursolic acid.