Pulmonary endothelial barrier dysfunction is a hallmark of clinical pulmonary edema and contributes to the development of acute lung injury(ALI).Here we reported that ruscogenin(RUS),an effective steroidal sapogenin o...Pulmonary endothelial barrier dysfunction is a hallmark of clinical pulmonary edema and contributes to the development of acute lung injury(ALI).Here we reported that ruscogenin(RUS),an effective steroidal sapogenin of Radix Ophiopogon japonicus,attenuated lipopolysaccharides(LPS)-induced pulmonary endothelial barrier disruption through mediating non-muscle myosin heavy chain IIA(NMMHC IIA)-Toll-like receptor 4(TLR4)interactions.By in vivo and in vitro experiments,we observed that RUS administration significantly ameliorated LPS-triggered pulmonary endothelial barrier dysfunction and ALI.Moreover,we identified that RUS directly targeted NMMHC IIA on its N-terminal and head domain by serial affinity chromatography,molecular docking,biolayer interferometry,and microscale thermophoresis analyses.Downregulation of endothelial NMMHC IIA expression in vivo and in vitro abolished the protective effect of RUS.It was also observed that NMMHC IIA was dissociated from TLR4 and then activating TLR4 downstream Src/vascular endothelial cadherin(VE-cadherin)signaling in pulmonary vascular endothelial cells after LPS treatment,which could be restored by RUS.Collectively,these findings provide pharmacological evidence showing that RUS attenuates LPS-induced pulmonary endothelial barrier dysfunction by inhibiting TLR4/Src/VE-cadherin pathway through targeting NMMHC IIA and mediating NMMHC IIA-TLR4 interactions.展开更多
基金supported by the National Natural Science Foundation of China(No.81773971,China)Double FirstClass University Project(No.CPU2018GF07,China)。
文摘Pulmonary endothelial barrier dysfunction is a hallmark of clinical pulmonary edema and contributes to the development of acute lung injury(ALI).Here we reported that ruscogenin(RUS),an effective steroidal sapogenin of Radix Ophiopogon japonicus,attenuated lipopolysaccharides(LPS)-induced pulmonary endothelial barrier disruption through mediating non-muscle myosin heavy chain IIA(NMMHC IIA)-Toll-like receptor 4(TLR4)interactions.By in vivo and in vitro experiments,we observed that RUS administration significantly ameliorated LPS-triggered pulmonary endothelial barrier dysfunction and ALI.Moreover,we identified that RUS directly targeted NMMHC IIA on its N-terminal and head domain by serial affinity chromatography,molecular docking,biolayer interferometry,and microscale thermophoresis analyses.Downregulation of endothelial NMMHC IIA expression in vivo and in vitro abolished the protective effect of RUS.It was also observed that NMMHC IIA was dissociated from TLR4 and then activating TLR4 downstream Src/vascular endothelial cadherin(VE-cadherin)signaling in pulmonary vascular endothelial cells after LPS treatment,which could be restored by RUS.Collectively,these findings provide pharmacological evidence showing that RUS attenuates LPS-induced pulmonary endothelial barrier dysfunction by inhibiting TLR4/Src/VE-cadherin pathway through targeting NMMHC IIA and mediating NMMHC IIA-TLR4 interactions.
文摘目的考察麦冬中主要皂苷元鲁斯可皂苷元(Rusco-gen in)抑制细胞黏附的作用,为深入研究其抗炎作用机制提供依据。方法采用MTT比色法检测Ruscogen in对人原髓性白血病细胞株HL-60细胞与正常或肿瘤坏死因子-α(TNF-α)活化的人脐静脉内皮细胞株ECV304细胞黏附的影响及其对ECV304与HL-60细胞增殖的影响。结果Ruscogen in 0.1,1.0μmol.L-1预处理ECV304细胞后,均抑制TNF-α诱导的ECV304细胞与HL-60细胞黏附的增加,Ruscogen in 0.001,0.01,0.1μmol.L-1预处理HL-60后,亦抑制TNF-α诱导的ECV304细胞与HL-60细胞黏附的增加;同时Ruscogen in在实验浓度范围内不影响ECV304细胞与HL-60细胞的增殖及二者之间的正常黏附。结论Ruscoge-n in可通过抑制HL-60细胞与活化的ECV304细胞之间的黏附作用,发挥抗炎活性。
