ABSTRACT
Objective:
To study the molecular mechanisms of
antioxidant effect and anti-inflammatory of
water extract of
Sophora flavescens (WSF) in
lipopolysaccharide (LPS)-induced RAW264.7
cells.
Methods:
The optimum concentration of WSF was evaluated by
CCK-8 assay. The inflammatory model was established with LPS by stimulating RAW264.7
cells in vitro. Then all
cells were divided into
control group, model group, WSF group and WSF
control group. The levels of ROS and NO were analyzed with
flow cytometry. Subsequently, the expression of iNOS, COX-2, Nrf2, and HO-1 was detected with qRT-
PCR and
Western blotting. Finally, the pro-inflammatory
cytokines IL-6, TNF-α and anti-inflammatory
cytokine IL-10 were detected by
ELISA.
Results:
The
CCK-8 assay revealed that 0.01 mg/mL WSF did not
affect the
cell viability. Compared with
control group, the LPS-induced inflammatory response could significantly increase the
production of NO and ROS, and the
IL-6 and TNF-α were also significantly increased (P < 0.05, 0.01, and 0.001). Furthermore, the expression of iNOS and COX-2 were significantly increased (P < 0.01, 0.001), but the expression of Nrf2 and HO-1 were inhibited (P < 0.05). However, compared with model group, the WSF group not only significantly decreased the levels of NO, ROS,
IL-6, and TNF-α, but also decreased the expression of iNOS and COX-2 (P < 0.05, 0.01, and 0.001). In contrast, the the level of
IL-10 and the expression of Nrf2 and HO-1 were significantly increased (P < 0.05, 0.01, and 0.001).
Conclusion:
These results suggested that SF exerted protective effect against LPS-induced inflammatory and oxidative responses in
RAW 264.7 cells by the activation of the Nrf2/HO-1 pathway.