摘要Background:Eucommia ulmoides Oliv.is a medicinal plant native to China,with its bark (Eucommiae Cortex) traditionally being used for medicinal purposes.Previous research has shown that Eucommia male flowers can exert anti-inflammatory,analgesic,antibacterial,and other pharmacological effects,including immune regulation.This study explored the anti-inflammatory effects of the 70％ ethanol extract of male flowers (EF) of E.ulmoides in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and LPS-administered mice.Methods:Cytotoxicity of EF for RAW 264.7 cells was investigated using Cell Counting Kit-8.The production of proinflammatory mediators,nitric oxide (NO),tumor necrosis factor (TNF)-α,interleukin (IL)-1β,and IL-6 was determined using enzyme-linked immunosorbent assays.IL-17,IL-23,and IL-10 mRNA levels were determined using quantitative real-time polymerase chain reaction.Activation of the nuclear factor (NF)-κB pathway in RAW 264.7 cells was investigated via Western blotting.In vivo anti-inflammatory effects of EF were studied in an LPS-induced acute inflammation mouse model by analyzing lung tissue histopathology,serum TNF-α and IL-6 levels,and myeloperoxidase (MPO) activity in lung tissue.Results:EF showed no significant cytotoxicity at concentrations from 10 to 60 μg/mL (cell viability ＞ 80％) in the CCK-8 cell viability assay.EF inhibited the RAW 264.7 cell proliferation (EF 60 μg/mL,120 μg/mL,and 250 μg/mL vs.negative control:87.31 ± 2.39 ％ vs.100.00±2.50％,P=0.001;79.01±2.56 vs.100.00±2.50％,P＜ 0.001;and 64.83±2.50 vs.100.00±2.50％,P＜ 0.001),suppressed NO (EF 20 μg/mL and 30 μg/mL vs.LPS only,288.81 ± 38.01 vs.447.68 ± 19.07 μmol/L,P=0.004;and 158.80 ± 45.14 vs.447.68 ± 19.07μmol/L,P＜0.001),TNF-α (LPS+EF vs.LPS only,210.20±13.85 vs.577.70±5.35pg/mL,P＜ 0.001),IL-1β (LPS+EF vs.LPS only,193.30 ± 10.80 vs.411.03 ± 42.28 pg/mL,P ＜ 0.001),and IL-6 (LPS+EF vs.LPS only,149.67 ± 11.60 vs.524.80 ± 6.24 pg/mL,P ＜ 0.001) secretion,and downregulated the mRNA expression of IL-17 (LPS+EF vs.LPS only,0.23 ± 0.02 vs.0.43 ± 0.12,P ＜ 0.001),IL-23 (LPS+EF vs.LPS only,0.29±0.01 vs.0.42±0.06,P=0.002),and IL-10 (LPS+EF vs.LPS only,0.30±0.01 vs.0.47±0.01,P=0.008) in LPS-stimulated RAW 264.7 cells.EF inhibited the LPS-induced NF-KB p65 (LPS+EF 20 μg/mL and 30 μg/mL vs.LPS only:0.78 ± 0.06 vs.1.17± 0.08,P ＜ 0.001;and 0.90± 0.06 vs.1.17± 0.08,P =0.002) and inhibitor of kappa B (IκBα) phosphorylation (LPS+EF 20 μg/mL IκB kinase (IKKα/β) phosphorylation (LPS+EF 30 μg/mL vs.LPS only,1.12±0.14 vs.1.71±0.25,P=0.002) in RAW 264.7 cells.Furthermore,EF 10 mg/kg and EF 20 mg/kg inhibited lung tissue inflammation in vivo and suppressed the serum TNF-α (LPS+EF 10 mg/kg and 20 mg/kg vs.LPS only,199.99± 186.49 vs.527.90±263.93 pg/mL,P=0.001;and 260.56 ± 175.83 vs.527.90±263.93 pg/mL,P=0.005),and IL-6 (LPS+EF 10 mg/kg and 20 mg/kg vs.LPS only,41.26 ± 30.42 vs.79.45 ± 14.16 pg/ml,P=0.011;and 42.01 ± 26.26 vs.79.45 ± 14.16 pg/mL,P =0.012) levels and MPO (LPS+EF 10 mg/kg and 20 mg/kg vs.LPS only,3.19 ± 1.78 vs.5.39 ± 1.51 U/g,P =0.004;and 3.32± 1.57 vs.5.39± 1.51U/g,P=0.006) activity in lung tissue.Conclusions:EF could effectively inhibit the expression of inflammatory factors and overactivation of neutrophils.Further investigation is needed to evaluate its potential for anti-inflammation therapy.