Abstract: Objective To study the effects of LXA4 to the releasing of inflammatory cytokines in obese rat. Methods Rats were used to create obesity model with high fat diet (HFD) and the control group were fed with normal diet (ND). These successfully established models were then divided into three subgroups, including the control group, LPS group and LXA4 intervention group. All of rats were killed after 12 hours and heart blood was collected to detect TNFα and IL-6 levels though ELISA. Western Blot experiments tested the activation in the downstream NF-kB and MAPK signaling pathways. Results Comparing with ND group, IL-6 and TNFα levels both increased significantly in HFD group（P<0.05）. After LPS injection, the levels of IL-6 and TNFα both increased in ND and HFD group（P<0.05）. However, LXA4 intervention can obviously decrease the releasing of IL-6 and TNFα（P<0.05）. Both NF-kB and MAPK signaling pathways activated obviously in HFD group comparing with ND group. In addition, LXA4 intervention can decrease the activation of NF-kB and MAPK signaling pathways caused by LPS in ND and HFD group. Conclusion LXA4 intervention can effectively reduce the serum levels of inflammatory cytokines and inhibit the activation of NF-kB and MAPK signaling pathways caused by LPS in obese rats, which revealing dual protective effects on obesity and inflammatory reaction.

Key words: LXA4, obesity, sepsis