Temperature-dependent influence of thiols upon glutathione levels in Chinese hamster ovary cells at cytotoxic concentrations.
Temperature-dependent influence of thiols upon glutathione levels in Chinese hamster ovary cells at cytotoxic concentrations.
复制标题
DOI：
--
复制
发表时间：
1985-12
期刊：
影响因子：
11.2
通讯作者：
R. Issels;S. Bourier;J. Biaglow;L. Gerweck;W. Wilmanns
中科院分区：
文献类型：
--
作者：
R. Issels;S. Bourier;J. Biaglow;L. Gerweck;W. Wilmanns
中国仓鼠卵巢细胞在不同温度(5摄氏度、37摄氏度、44摄氏度)下暴露于巯基化合物半胱胺，其浓度为已知的产生活性氧物种的浓度。在37摄氏度，细胞谷胱甘肽(GSH)含量随药物暴露时间(2小时)线性增加，与未经处理的细胞或药物治疗期间保持在5摄氏度的细胞相比。半胱胺诱导的GSH在44℃时比37℃时升高2-4倍，且在较高温度下表现出饱和效应。在药物治疗期间，谷氨酰半胱氨酸合成酶抑制剂D-丁硫氨酸-S、R-亚磺胺或在无半胱氨酸的培养液中孵育均可完全阻断GSH的升高。37℃的半胱胺单独或与44℃的加热联合作用后22h内，半胱胺诱导的细胞GSH含量升高均降至对照范围。其他硫醇如半胱胺，即半胱氨酸、N-乙酰半胱氨酸和二硫苏糖醇，被发现在诱导中国仓鼠卵巢细胞GSH升高方面的潜力相似。在与半胱胺(0-2 mM)相同的浓度范围内，观察到这些巯基化合物的细胞毒性作用，但只有当细胞以低密度(10(2)-10(4)个细胞/瓶)培养时，才能被过氧化氢酶(50微克/毫升)完全阻断。相反，硫醇处理(0.8 mM)后GSH的升高不受过氧化氢酶的影响。这些数据表明，硫醇联合高温处理可导致中国仓鼠卵巢细胞GSH生物合成的快速增加，这似乎不依赖于硫醇自氧化同时产生的活性氧物种。
Chinese hamster ovary cells were exposed to the sulfhydryl compound cysteamine at different temperatures (5 degrees C, 37 degrees C, 44 degrees C) at concentrations known to generate activated oxygen species. At 37 degrees C, the cellular glutathione (GSH) content increased linearly over the time of drug exposure (2 h) as compared to untreated cells or to cells kept at 5 degrees C during drug treatment. The 2-4-fold increase in GSH induced by cysteamine was more rapid at 44 degrees C than at 37 degrees C and showed a saturation effect at the higher temperature. The elevation of GSH could be completely blocked by DL-buthionine-S,R-sulfoximine, an inhibitor of gamma-glutamylcysteine synthetase, or by incubation in a cystine-free medium during the period of drug treatment. The increased cellular GSH content induced by cysteamine alone at 37 degrees C or combined with heat at 44 degrees C decreased to the range of control values within 22 h after either treatment. Other thiols like cysteamine, namely cysteine, N-acetylcysteine, and dithiothreitol, were found to be similar in their potential to induce GSH elevation in Chinese hamster ovary cells. Cytotoxic effects of these sulfhydryl compounds were observed in the same concentration range as that for cysteamine (0-2 mM), but only if cells were plated at low densities (10(2)-10(4) cells/flask), and were completely blocked by the addition of catalase (50 micrograms/ml). In contrast, the elevation of GSH after thiol treatment (0.8 mM) was not modified by catalase. The data suggest that thiol treatment combined with hyperthermia leads to a rapid increase of GSH biosynthesis in Chinese hamster ovary cells which seems to be independent of the simultaneous generation of activated oxygen species by thiol autoxidation.