Aqueous Extract of Gracilaria tenuistipitata Suppresses LPS-Induced NF-κB and MAPK Activation in RAW 264.7 and Rat Peritoneal Macrophages and Exerts Hepatoprotective Effects on Carbon Tetrachloride-Treated Rat
Figure 4
Effect of AEGT on NF-κB activation in LPS-stimulated RAW 264.7 cells.
(A) The RAW264.7 cells were seeded in a 24-well plate, and treated with 400 or 800 µg/ml AEGT for 1 h and then incubated with 1 µg/ml LPS for 2 h. The levels of total protein and phosphorylated IKKα, IKKβ, and IκBα were analyzed by western blot analysis with specific antibodies. The relative value of the LPS- group or AEGT/LPS-treated group over the untreated group was measured by densitometry following normalization to cellular GAPDH levels. In the NF-κB activation assay, the cells were transfected with a pNFκB-Luc reporter plasmid. Subsequently, the transfected cells were treated with 400 or 800 µg/ml AEGT for 1 h, and then incubated with 1 µg/ml LPS for 2 h. The cell lysates and nuclear fraction were collected for western blot (B) and luciferase activity (C) analyses, respectively. The basal level of promoter activity in the AEGT/LPS-untreated cells was defined as 1. Error bars indicate the means ± SD of three independent experiments. *P<0.05; **P<0.01.