Analysis of methylglyoxal metabolism in CHO cells grown in culture
Analysis of methylglyoxal metabolism in CHO cells grown in culture
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DOI：
10.1007/s10616-005-1920-6
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发表时间：
2005-01-01
期刊：
影响因子：
2.2
通讯作者：
Chaplen, FWR
中科院分区：
文献类型：
--
作者：
Kingkeohoi, S;Chaplen, FWR
最近的证据表明，一些未知或特征不明的因素强烈影响培养中的细胞生长和功能。为了最大限度地提高文化生产力，必须隔离这些因素。甲基乙二醛 (MG) 是一种有效的蛋白质和核酸修饰剂，已被确定为与细胞死亡相关的信号传导途径的参与者，并且已知对培养细胞有害。该化合物在所有哺乳动物系统中通过糖酵解途径中间体自发消除磷酸盐而产生。定性描述在不存在酶加合物形成的情况下蛋白质相关 MG 的细胞分布的动力学模型预测可逆结合的 MG 水平远低于培养的 CHO 细胞中测量的水平。这表明通过酶介导的机制对蛋白质进行靶向修饰是细胞甲基乙二醛的重要环节。该模型通过测量通过乙二醛酶途径生成 D-乳酸（哺乳动物系统中 MG 代谢的独特终产物）的碳通量进行了验证。使用分批培养的 CHO 细胞测量到 D-乳酸通量高达 16.8 mmol ml-1 堆积的细胞(-1) day(-1)，比正常组织中的多 100 倍。
Recent evidence suggests that several unknown or ill-characterized factors strongly influence cell growth and function in culture. Isolating these factors is necessary in order to maximize culture productivities. Methylglyoxal (MG), a potent protein and nucleic acid modifying agent, has been identified as a player in the signaling pathways associated with cell death and is known to be detrimental to cultured cells. This compound is produced in all mammalian systems by spontaneous phosphate elimination from glycolytic pathway intermediates. A kinetic model that qualitatively describes the cellular distribution of protein-associated MG in the absence of enzymatic adduct formation predicted far lower levels of reversibly bound MG than measured in cultured CHO cells. This suggests that the targeted modification of proteins through enzymatically mediated mechanisms is a significant slink for cellular methylglyoxal. The model was validated with measurements of carbon flux through the glyoxalase pathway to D-lactic acid, a unique end product of MG metabolism in mammalian systems. Fluxes to D-lactic acid of up to 16.8 mmol ml-packed cells(-1) day(-1) were measured with CHO cells grown in batch culture or 100-fold more than found in normal tissues.