Mokuno K, Ohtani K, Suzumura A, Kiyosawa K, Hirose Y, Kawai K, Kato K
Department of Neurology, Nagoya University School of Medicine, Japan.
J Neurochem. 1994 Aug;63(2):612-6. doi: 10.1046/j.1471-4159.1994.63020612.x.
To determine whether cytokines or lipopolysaccharide (LPS) are involved in the induction of superoxide dismutase (SOD) in the nervous system, we examined the effects of these substances on the levels of SOD in cultured mouse astrocytes. Treatment of astrocytes with 10(2) to 10(4) U/ml tumor necrosis factor-alpha for 3 days increased the levels of Mn SOD in a dose- and time-dependent manner to as much as six times the level under nontreated conditions. Treatment with 1.0 microgram/ml LPS for 3 days elicited a fourfold increase in levels of Mn SOD, and the effect of LPS was also dose dependent. Furthermore, Mn SOD in astrocytes was induced by a 3-day exposure to interleukin-1 alpha at concentrations of 10(2) or 10(3) U/ml. However, these stimuli had no effect on levels of copper-zinc SOD (Cu/Zn SOD) in astrocytes. By contrast, interferon-gamma did not change the levels of either Mn or Cu/Zn SOD in the cells. The results indicate that the selective induction of Mn SOD by cytokines and LPS, which has been observed in nonnervous tissues, may also occur in nervous tissues. The induction of Mn SOD may represent a mechanism for protection of cells from oxidative stress.
为了确定细胞因子或脂多糖（LPS）是否参与神经系统中超氧化物歧化酶（SOD）的诱导，我们研究了这些物质对培养的小鼠星形胶质细胞中SOD水平的影响。用10²至10⁴U/ml肿瘤坏死因子-α处理星形胶质细胞3天，可使锰超氧化物歧化酶（Mn SOD）水平呈剂量和时间依赖性增加，最高可达未处理条件下水平的6倍。用1.0μg/ml LPS处理3天可使Mn SOD水平增加4倍，且LPS的作用也呈剂量依赖性。此外，星形胶质细胞中的Mn SOD可通过暴露于浓度为10²或10³U/ml的白细胞介素-1α 3天来诱导。然而，这些刺激对星形胶质细胞中铜锌超氧化物歧化酶（Cu/Zn SOD）的水平没有影响。相比之下，干扰素-γ并未改变细胞中Mn SOD或Cu/Zn SOD的水平。结果表明，在非神经组织中观察到的细胞因子和LPS对Mn SOD的选择性诱导在神经组织中也可能发生。Mn SOD的诱导可能代表一种保护细胞免受氧化应激的机制。
