ErkⅠ/Ⅱ介导姜黄素对慢性脂多糖诱导的脊髓突触可塑性损害的拮抗作用

ErkⅠ/Ⅱ Mediated Antagonised Effect of Curcumin on Chronic Exposure to LPS induced Impairment of Spinal Synaptic Plasticity

目的探讨ErkⅠ/Ⅱ与姜黄素对慢性脂多糖(LPS)诱导的脊髓背角C-纤维诱发电位长时程增强(LTP)的作用。方法在大鼠分别腹腔注射LPS(3 mg/kg)、姜黄素(300 mg/kg)、姜黄素(300 mg/kg)联合LPS(3 mg/kg)7 d后在脊髓腰膨大部记录背角浅层神经元C-纤维诱发电位,观察姜黄素对脊髓LTP的效应,并应用蛋白质印迹法检测不同条件下ErkⅠ/Ⅱ和NF-κB蛋白的表达。结果①慢性给予LPS可显著降低脊髓LTP,此效应可被姜黄素所抑制。②LPS可显著上调脊髓磷酸化的ErkⅠ/Ⅱ蛋白表达水平,该增强效应为姜黄素所显著抑制。③姜黄素可显著拮抗LPS上调脊髓磷酸化NF-κB的蛋白表达水平。结论姜黄素对LPS诱导的脊髓LTP损害的拮抗作用可能是通过ErkⅠ/Ⅱ信号途径介导的。

Objective The role of external-signal regulated kinaseⅠ/Ⅱ（ErkⅠ/Ⅱ） and Curcumin on chronic exposure to lipopolysaccharide（LPS） induced inhibition of spinal long-term potentiation（LTP） is evaluated. MethodsThe C-fiber evoked field potentials were recorded at the superficial layers of spinal dorsal horn at the lumbar enlargement to observe the effect of Curcumin on the chronic exposure to LPS induced inhibition of LTP and expressions of phospho-ErkⅠ/Ⅱand phospho-NF-κB in LPS or Curcumin-treated rats were measured by immunoblotting technique. Results①Spinal LTP was significantly attenuated by chronic exposure to LPS and this effect was robustly inhibited by curcumin.But Curcumin itself never affected spinal LTP by tetani.②Eleveated phospho-ErkⅠ/Ⅱ expression in LPS-treated rats was significantely suppressed by Curcumin.③Eleveated expression of phospho-NF-κB in LPS-treated rats was robustly inhibited by Curcumin. ConclusionAntagonised effect of Curcumin on chronic exposure to LPS induced impairment of spinal LTP might be mediated via ErkⅠ/Ⅱ signalling pathway.