Effect of 4-
-methylhonokiol on LPS-induced ROS, NO, PGE
, TNF-α and IL-1β generation in cultured astrocytes. Astrocytes were treated with LPS (1 μM) and 4-O-methylhonokiol (0.5-2 μM). (A) NO level was determined in the supernatant of astrocytes by Griess reaction as described in Methods. (B) PGE2 level was determined in the supernatant of astrocytes by PGE2 EIA kit. (C) Intracellular ROS levels were determined by measuring DCF fluorescence. (D), (E) and (F) mRNA levels of TNF-α and IL-1β were determined by real time PCR as described in Methods. (G) and (H) protein levels of TNF-α and IL-1β were determined by specific ELISA kits as described in Methods. The data indicated in the each band are means ± S.D. from 5 mice brains. Values represent means ± S.D. of three independent experiments performed in triplicate. #, Significantly different from control group (p < 0.05). *, Significantly different from LPS-treated group (p < 0.05). Control, saline-treated group. LPS, lipopolysaccharide. MH, 4-O-methylhonokiol.