Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine.
National Bogomolets Medical University, Kyiv, Ukraine.
Endocr Regul. 2021 May 21;55(2):72-82. doi: 10.2478/enr-2021-0009.
The aim of the present investigation was to study the impact of glucose and gluta-mine deprivations on the expression of genes encoding EDN1 (endothelin-1), its cognate receptors (EDNRA and EDNRB), and ECE1 (endothelin converting enzyme 1) in U87 glioma cells in response to knockdown of ERN1 (endoplasmic reticulum to nucleus signaling 1), a major signaling pathway of endoplasmic reticulum stress, for evaluation of their possible implication in the control of glioma growth through ERN1 and nutrient limitations. The expression level of EDN1, its receptors and converting enzyme 1 in control U87 glioma cells and cells with knockdown of ERN1 treated by glucose or glutamine deprivation by quantitative polymerase chain reaction was studied. We showed that the expression level of and genes was significantly up-regulated in control U87 glioma cells exposure under glucose deprivation condition in comparison with the glioma cells, growing in regular glucose containing medium. We also observed up-regulation of gene expression in U87 glioma cells exposure under glutamine deprivation as well as down-regulation of the expression of EDN1 and EDNRA mRNA, being more significant for EDN1. Furthermore, the knockdown of ERN1 signaling enzyme function significantly modified the response of most studied gene expressions to glucose and glutamine deprivation conditions. Thus, the ERN1 knockdown led to a strong suppression of gene expression under glucose deprivation, but did not change the effect of glutamine deprivation on its expression. At the same time, the knockdown of ERN1 signaling introduced the sensitivity of gene to both glucose and glutamine deprivations as well as completely removed the impact of glucose deprivation on the expression of gene. The results of this study demonstrated that the expression of endothelin-1, its receptors, and genes is preferentially sensitive to glucose and glutamine deprivations in gene specific manner and that knockdown of ERN1 significantly modified the expression of , , and genes in U87 glioma cells. It is possible that the observed changes in the expression of studied genes under nutrient deprivation may contribute to the suppressive effect of ERN1 knockdown on glioma cell proliferation and invasiveness.
本研究旨在研究葡萄糖和谷氨酰胺剥夺对 U87 神经胶质瘤细胞中编码 EDN1（内皮素-1）、其同源受体（EDNRA 和 EDNRB）和 ECE1（内皮素转化酶 1）的基因表达的影响，以评估它们在通过 ERN1 和营养限制控制神经胶质瘤生长中的可能作用。通过定量聚合酶链反应研究了对照 U87 神经胶质瘤细胞和 ERN1 敲低的细胞在葡萄糖或谷氨酰胺剥夺下的 EDN1、其受体和转化酶 1 的表达水平。我们表明，与在常规含葡萄糖培养基中生长的神经胶质瘤细胞相比，在葡萄糖剥夺条件下暴露的对照 U87 神经胶质瘤细胞中 和 基因的表达水平显著上调。我们还观察到在谷氨酰胺剥夺下 U87 神经胶质瘤细胞中 基因表达的上调以及 EDN1 和 EDNRA mRNA 表达的下调，对于 EDN1 更为显著。此外，ERN1 信号酶功能的敲低显著改变了大多数研究基因表达对葡萄糖和谷氨酰胺剥夺条件的反应。因此，ERN1 敲低导致在葡萄糖剥夺下 基因表达的强烈抑制，但不改变谷氨酰胺剥夺对其表达的影响。同时，ERN1 信号的敲低使 基因对葡萄糖和谷氨酰胺剥夺都敏感，并完全消除了葡萄糖剥夺对 基因表达的影响。本研究的结果表明，内皮素-1、其受体和 基因的表达以基因特异性的方式优先对葡萄糖和谷氨酰胺剥夺敏感，而 ERN1 的敲低显著改变了 U87 神经胶质瘤细胞中 、 和 基因的表达。在营养剥夺下观察到的研究基因表达的变化可能有助于解释 ERN1 敲低对神经胶质瘤细胞增殖和侵袭性的抑制作用。
