Kawasaki Toshiyuki, Kitao Tatsuya, Nakagawa Katsuhiro, Fujisaki Hiroko, Takegawa Yoshimi, Koda Ken, Ago Yukio, Baba Akemichi, Matsuda Toshio
Laboratory of Medicinal Pharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan.
Glia. 2007 Oct;55(13):1325-33. doi: 10.1002/glia.20541.
Nitric oxide induces apoptosis-like cell death in cultured astrocytes, but the exact mechanism is not known. This study further characterized the mechanism of nitric oxide-induced cytotoxicity, and examined the effect of edaravone, a radical scavenger, on cytotoxicity. Treatment of cultured rat astrocytes with sodium nitroprusside (SNP), a nitric oxide donor, for 72 h, decreased cell viability by causing apoptosis-like cell death. The injury was accompanied by increases in the production of reactive oxygen species and in the level of nuclear apoptosis-inducing factor, but not in caspase activity. SNP-induced cytotoxicity was blocked by the c-jun N-terminal protein kinase (JNK) inhibitor SP600125 (20 microM), the p38 mitogen-activated protein (MAP) kinase inhibitor SB203580 (20 microM), and the extracellular signal-regulating kinase (ERK) inhibitor U0126 (10 microM), and the nitric oxide donor stimulated the phosphorylation of p38 MAP kinase, JNK, and ERK. Edaravone (10 microM) protected astrocytes against SNP-induced cell injury and it inhibited SNP-induced phosphorylation of p38 MAP kinase, JNK, and ERK, and the production of reactive oxygen species. Edaravone also attenuated SNP-induced increase in nuclear apoptosis-inducing factor levels. These results suggest that MAP kinase pathways play a key role in nitric oxide-induced apoptosis and that edaravone protects against nitric oxide-induced cytotoxicity by inhibiting nitric oxide-induced MAP kinase activation in astrocytes.
一氧化氮可诱导培养的星形胶质细胞发生凋亡样细胞死亡，但其确切机制尚不清楚。本研究进一步阐述了一氧化氮诱导细胞毒性的机制，并检测了自由基清除剂依达拉奉对细胞毒性的影响。用一氧化氮供体硝普钠（SNP）处理培养的大鼠星形胶质细胞72小时，通过诱导凋亡样细胞死亡降低细胞活力。这种损伤伴随着活性氧生成增加和细胞核凋亡诱导因子水平升高，但半胱天冬酶活性未升高。SNP诱导的细胞毒性被c-jun氨基末端蛋白激酶（JNK）抑制剂SP600125（20微摩尔）、p38丝裂原活化蛋白（MAP）激酶抑制剂SB203580（20微摩尔）和细胞外信号调节激酶（ERK）抑制剂U0126（10微摩尔）阻断，且一氧化氮供体刺激p38 MAP激酶、JNK和ERK的磷酸化。依达拉奉（10微摩尔）可保护星形胶质细胞免受SNP诱导的细胞损伤，抑制SNP诱导的p38 MAP激酶、JNK和ERK磷酸化以及活性氧的生成。依达拉奉还可减轻SNP诱导的细胞核凋亡诱导因子水平升高。这些结果表明，MAP激酶途径在一氧化氮诱导的凋亡中起关键作用，依达拉奉通过抑制星形胶质细胞中一氧化氮诱导的MAP激酶激活来保护细胞免受一氧化氮诱导的细胞毒性。
