Figure 1.

Effect of Pa-ME on NO production and cell viability. (a, b, and c) Cells were pretreated with Pa-ME or standard compounds [Indo (indomethacin) and L-NAME] and incubated for 24 h with TLR ligands (LPS, pam3CSK4, and poly(I:C)). The levels of NO (a and b) and PGE₂ (c) were analyzed by Griess assay or EIA from the culture supernatant of RAW264.7 cells (a and c) or peritoneal macrophages (b) which were stimulated by LPS (1 μg/ml), poly(I:C) (200 μg/ml), and pam3CSK4 (10 μg/ml) (right panel) in the presence or absence of Pa-ME or L-NAME. (d) Viability of RAW264.7 cells (left panel) or peritoneal macrophages (right panel) was determined by MTT assay. (e) The phytochemical profile of Pa-ME was analyzed by HPLC with standard flavonoids, quercetin, luteolin, and kaempferol [Area]. ^∗P < 0.05 and ^∗∗P < 0.01 compared with control group.