FIG. 1.

LJ inhibits the production of NO (A) and PGE₂ (B) in LPS-stimulated BV-2 microglial cells. Cells were pretreated with the indicated concentrations of LJ for 30 min and then exposed to 100 ng/mL of LPS for 24 h. The concentration of nitrite in the culture medium was then determined by Griess reagent. PGE₂ levels were measured in the culture medium using a commercial ELISA kit. Data are presented as the mean±SEM (n=6). LJ attenuates expression of protein and mRNA levels for iNOS (C, E) and COX-2 (D, F) in LPS-induced BV-2 microglial cells. Cells were pretreated with the indicated concentrations of LJ for 30 min and then exposed to 100 ng/mL of LPS for 24 h (C, D). The expression of iNOS, COX-2, and β-actin was detected by western blot analysis. Cells were pretreated with the indicated concentrations of LJ for 30 min and then exposed to 100 ng/mL of LPS for 6 h (E, F). mRNA levels of iNOS, COX-2, and β-actin were determined by RT-PCR. Densitometric results are presented as the mean±SEM (n=3). ***P<.001 compared with the control group. ^##P<.01 and ^###P<.001 compared with the LPS-treated group. COX-2, cyclooxygenase-2; ELISA, enzyme-linked immunosorbent assay; iNOS, inducible nitric oxide synthase; LJ, Lonicera japonica THUNB.; LPS, lipopolysaccharide; NO, nitric oxide; PGE₂, prostaglandin E₂; RT-PCR, reverse transcription–polymerase chain reactions.