Lum Julian J, Bui Thi, Gruber Michaela, Gordan John D, DeBerardinis Ralph J, Covello Kelly L, Simon M Celeste, Thompson Craig B
Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Genes Dev. 2007 May 1;21(9):1037-49. doi: 10.1101/gad.1529107. Epub 2007 Apr 16.
Mammalian cells are believed to have a cell-intrinsic ability to increase glucose metabolism in response to hypoxia. Here we show that the ability of hematopoietic cells to up-regulate anaerobic glycolysis in response to hypoxia is dependent on receptor-mediated signal transduction. In the absence of growth factor signaling, hematopoietic cells fail to express hypoxia-inducible transcription factor (Hif-1alpha) mRNA. Growth factor-deprived hematopoietic cells do not engage in glucose-dependent anabolic synthesis and neither express Hif-1alpha mRNA nor require HIF-1alpha protein to regulate cell survival in response to hypoxia. However, HIF-1alpha is adaptive for the survival of growth factor-stimulated cells, as suppression of HIF-1alpha results in death when growing cells are exposed to hypoxia. Growth factor-dependent HIF-1alpha expression reprograms the intracellular fate of glucose, resulting in decreased glucose-dependent anabolic synthesis and increased lactate production, an effect that is enhanced when HIF-1alpha protein is stabilized by hypoxia. Together, these data suggest that HIF-1alpha contributes to the regulation of growth factor-stimulated glucose metabolism even in the absence of hypoxia.
哺乳动物细胞被认为具有一种细胞内在能力,可在缺氧时增加葡萄糖代谢。在此我们表明,造血细胞在缺氧时上调无氧糖酵解的能力依赖于受体介导的信号转导。在缺乏生长因子信号时,造血细胞无法表达缺氧诱导转录因子(Hif-1α)mRNA。缺乏生长因子的造血细胞不参与葡萄糖依赖性合成代谢,既不表达Hif-1α mRNA,也不需要HIF-1α蛋白来调节缺氧时的细胞存活。然而,HIF-1α对生长因子刺激的细胞存活具有适应性,因为当生长中的细胞暴露于缺氧时,抑制HIF-1α会导致细胞死亡。生长因子依赖性HIF-1α表达重新编程葡萄糖的细胞内命运,导致葡萄糖依赖性合成代谢减少,乳酸生成增加,当HIF-1α蛋白因缺氧而稳定时,这种效应会增强。总之,这些数据表明,即使在没有缺氧的情况下,HIF-1α也有助于调节生长因子刺激的葡萄糖代谢。