Institute of Cerebrovascular Diseases, Affiliated Hospital of Qingdao University, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Taishan Scholars Construction Project Excellent Innovative Team of Shandong Province, Qingdao, 266003, China.
Institute of Integrative Medicine, Qingdao University Medical College, Qingdao, 266021, China.
J Mol Neurosci. 2018 Jan;64(1):144-155. doi: 10.1007/s12031-017-1012-z. Epub 2017 Dec 18.
Mitochondrial membrane permeability is closely related to cerebral ischemia/reperfusion (I/R) injury. This paper explored the neuroprotective effect of picroside II (Picr), which inhibits the permeability of mitochondrial permeability transition pore (mPTP) and endonuclease G (EndoG) release from mitochondria into cytoplasm after cerebral I/R in rats. After 2 h of cerebral ischemia and 24 h of reperfusion in rats with different intervention measures, the neurobehavioral function, infarction volume, and reactive oxygen species (ROS) content in brain tissues were observed by modified neurological severity scale (mNSS), triphenyl tetrazolium chloride (TTC) staining, and enzyme-linked immunosorbent assay, respectively. The permeability of mPTP was assayed using spectrophotometry. The morphology and apoptotic cells of brain tissues were observed by hematoxylin-eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively. The expressions of EndoG and voltage-dependent anion channel 1 (VDAC1) were determined by immunohistochemical assay and western blot. The Picr group exhibited clear decreases in mNSS scores, ROS content, number of apoptotic cells, mPTP permeability and expression of VDAC1, and EndoG in cytoplasm and nuclei, and the morphology of brain tissue was improved as compared with the model group (P < 0.05). Picr could attenuate cerebral I/R injury by downregulating the expression of VDAC1 and decreasing the permeability of mPTP, thereby inhibiting EndoG release from mitochondria into cytoplasm.
线粒体膜通透性与脑缺血/再灌注（I/R）损伤密切相关。本研究探讨了毛兰素 II（Picr）的神经保护作用，毛兰素 II 可抑制脑 I/R 后大鼠线粒体通透性转换孔（mPTP）通透性增加，并抑制线粒体内切核酸酶 G（EndoG）释放到细胞质。采用改良神经功能缺损评分（mNSS）、三苯基四氮唑氯（TTC）染色和酶联免疫吸附试验分别观察不同干预措施后大鼠脑缺血 2 h 再灌注 24 h 后的神经行为功能、脑梗死体积和脑组织中活性氧（ROS）含量，采用分光光度法检测 mPTP 通透性，苏木精-伊红（HE）染色和末端脱氧核苷酸转移酶 dUTP 缺口末端标记（TUNEL）法观察脑组织形态和凋亡细胞，免疫组化和 Western blot 法检测 EndoG 和电压依赖性阴离子通道 1（VDAC1）的表达。Picr 组 mNSS 评分、ROS 含量、凋亡细胞数、mPTP 通透性及细胞质和核内 VDAC1、EndoG 表达均明显降低，脑组织形态改善，与模型组比较差异有统计学意义（P<0.05）。下调 VDAC1 的表达，降低 mPTP 的通透性，抑制 EndoG 从线粒体释放到细胞质，可减轻 Picr 对脑 I/R 损伤。
