Study on Protective Effects of the Ethanol Extract of Garcinia oblongifolia on LPS-induced RAW 264.7 Cell Inflammatory Injury / 中国药房

ABSTRACT

OBJECTIVE：To investigate the anti-inflammatory activity of 70％ ethanol extracts from Garcinia oblongifolia （GOEE）on LPS-induced RAW 264.7 cells and its potential molecular mechanism. METHODS ：GOEE was obtained after the fresh G. oblongifolia epicarp refluxed with 70％ ethanol. The contents of total phenol and total flavonoids were determined by Folin-Ciocalteau assay and UV spectrophotometer. MTT assay was used to detect the cytotoxicity of different doses of GOEE. The inflammatory model was induced in RAW 264.7 cells by lipopolysa- ccharide （LPS）. Using dexamethasone and N-acetyl-L-cysteine as positive control ，Griess assay and 2′，7′-dichloro- fluorescein assay were used to detect the contents of NO in cell culture medium and ROS in cells. The levels of TNF-α，IL-6，and IL- 1β in cell culture medium were measured by ELISA. The protein expression of p 65，p-p65，IκBα，p-IκBα，HO-1 in cells and NRF 2 in nucleus were determined by using Western blotting assay. RESULTS：The contents of total phenol and flavonoids in GOEE were （20.191±1.264）and（12.571±0.020）mg/g，respectively. At the concentration below 500 μ g/mL， GOEE had no significantly effect on survival rate of RAW 264.7 cells（P＞ 294043）0.05）. Compared with control group ，the contents of NO and ROS，the levels of TNF-α，IL-6 and IL- 1β，ratio of p-p 65 top65，ratio of p-IκBα to IκBα，protein expression of NRF 2 were increased significantly in LPS model group （P＜0.05 or P＜0.01）. Compared with LPS model group ，the contents of NO（except for GOEE 50 μg/mL group）and ROS ，the levels of TNF-α，IL-6 and IL- 1β，ratio of p-p 65 to p 65 and ratio of p-IκBα to IκBα were decreased significantly in GOEE groups and positive control groups ，while protein expression of HO- 1 and NRF 2 were increased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS：GOEE attenuates LPS-induced macrophages inflammation injury by inhibiting the inflammatory response and the phosphorylation of NF-κB pathway，promoting NRF 2 protein transportation to the nucleus.