Weber Nina C, Toma Octavian, Wolter Jessica I, Wirthle Nicole M, Schlack Wolfgang, Preckel Benedikt
Department of Anesthesiology, University Hospital of Düsseldorf, Germany.
Br J Pharmacol. 2005 Oct;146(3):445-55. doi: 10.1038/sj.bjp.0706324.
We previously demonstrated that the anesthetic gas xenon exerts cardioprotection by preconditioning in vivo via activation of protein kinase C (PKC)-epsilon and p38 mitogen-activated protein kinase (MAPK). P38 MAPK interacts with the actin cytoskeleton via the MAPK-activated protein kinase-2 (MAPKAPK-2) and heat-shock protein 27 (HSP27). The present study further elucidated the underlying molecular mechanism of xenon-induced preconditioning (Xe-PC) by focusing on a potential link of xenon to the cytoskeleton. Anesthetized rats received either xenon (Xe-PC, n = 6) or the volatile anesthetic isoflurane (Iso-PC, n = 6) during three 5-min periods interspersed with two 5-min and one final 10-min washout period. Control rats (n = 6) remained untreated for 45 min. Additional rats were either pretreated with the PKC inhibitor Calphostin C (0.1 mg kg(-1)) or with the p38 MAPK inhibitor SB203580 (1 mg kg(-1)) with and without anesthetic preconditioning (each, n = 6). Hearts were excised for immunohistochemistry of F-actin fibers and phosphorylated HSP27. Phosphorylation of MAPKAPK-2 and HSP27 were assessed by Western blot. HSP27 and actin colocalization were investigated by co-immunoprecipitation. Xe-PC induced phosphorylation of MAPKAPK-2 (control 1.0 +/- 0.2 vs Xe-PC 1.6 +/- 0.1, P < 0.05) and HSP27 (control 5.0 +/- 0.5 vs Xe-PC 9.8 +/- 1.0, P < 0.001). Both effects were blocked by Calphostin C and SB203580. Xe-PC enhanced translocation of HSP27 to the particulate fraction and increased F-actin polymerization. F-actin and pHSP27 were colocalized after Xe-PC. Xe-PC activates MAPKAPK-2 and HSP27 downstream of PKC and p38 MAPK. These data link Xe-PC to the cytoskeleton, revealing new insights into the mechanisms of Xe-PC in vivo.
我们之前证明，麻醉气体氙通过激活蛋白激酶C（PKC）-ε和p38丝裂原活化蛋白激酶（MAPK）在体内进行预处理，从而发挥心脏保护作用。P38 MAPK通过MAPK活化蛋白激酶-2（MAPKAPK-2）和热休克蛋白27（HSP27）与肌动蛋白细胞骨架相互作用。本研究通过关注氙与细胞骨架的潜在联系，进一步阐明了氙诱导预处理（Xe-PC）的潜在分子机制。麻醉大鼠在三个5分钟期间接受氙（Xe-PC，n = 6）或挥发性麻醉药异氟烷（Iso-PC，n = 6），期间穿插两个5分钟和一个最后的10分钟洗脱期。对照大鼠（n = 6）未接受处理45分钟。另外的大鼠用PKC抑制剂Calphostin C（0.1 mg kg⁻¹）或p38 MAPK抑制剂SB203580（1 mg kg⁻¹）进行预处理，有或没有麻醉预处理（每组，n = 6）。取出心脏进行F-肌动蛋白纤维和磷酸化HSP27的免疫组织化学分析。通过蛋白质印迹法评估MAPKAPK-2和HSP27的磷酸化。通过免疫共沉淀研究HSP27和肌动蛋白的共定位。Xe-PC诱导MAPKAPK-2的磷酸化（对照1.0±0.2 vs Xe-PC 1.6±0.1，P < 0.05）和HSP27的磷酸化（对照5.0±0.5 vs Xe-PC 9.8±1.0，P < 0.001）。这两种效应均被Calphostin C和SB203580阻断。Xe-PC增强了HSP27向颗粒部分的转位并增加了F-肌动蛋白聚合。Xe-PC后F-肌动蛋白和pHSP27共定位。Xe-PC在PKC和p38 MAPK下游激活MAPKAPK-2和HSP27。这些数据将Xe-PC与细胞骨架联系起来，揭示了体内Xe-PC机制的新见解。
