Glutamate metabolism in HIV-1 infected macrophages: Role of HIV-1 Vpr
Glutamate metabolism in HIV-1 infected macrophages: Role of HIV-1 Vpr
复制标题
DOI：
10.1080/15384101.2016.1190054
复制
发表时间：
2016-01-01
期刊：
影响因子：
4.3
通讯作者：
Barrero, Carlos A.
中科院分区：
文献类型：
--
作者：
Datta, Prasun K.;Deshmane, Satish;Barrero, Carlos A.
HIV-1感染的巨噬细胞在AIDS的神经发病机制中起重要作用。HIV-1病毒蛋白R（Vpr）不仅促进HIV-1感染，而且有助于在巨噬细胞中的长期存在。我们以前的研究使用SILAC为基础的蛋白质组学分析表明，在糖酵解途径和三羧酸（TCA）循环中的关键代谢酶的表达改变响应Vpr在巨噬细胞中的表达。我们假设Vpr诱导的糖酵解和TCA循环调节HIV-1感染的巨噬细胞中谷氨酸的代谢和释放，我们利用多反应监测（MRM）靶向代谢组学技术，在细胞内和细胞外水平上以时间依赖的方式评估Vpr和HIV-1诱导的巨噬细胞中特异性代谢物的量。此外，使用稳定同位素标记的葡萄糖和MRM靶向代谢组学测定来评估在Vpr过表达的巨噬细胞和HIV-1感染的巨噬细胞中谷氨酸的从头合成和释放，贯穿糖酵解途径和TCA循环活化的代谢通量。在Vpr表达和HIV-1感染的巨噬细胞的细胞外环境中谷氨酸释放和β-酮戊二酸（-KG）和谷氨酰胺的积累。有趣的是，谷氨酸池和其他细胞内中间产物（葡萄糖-6-磷酸（G6 P）、果糖-6-磷酸（F6 P）、柠檬酸盐、苹果酸盐、-KG和谷氨酰胺）除富马酸盐外均显示下降趋势，与Vpr过表达巨噬细胞中观察到的细胞外间隙中谷氨酰胺积累相反，我们的研究表明，在HIV-1感染者中，Vpr诱导的线粒体谷氨酸代谢失调，1感染的巨噬细胞常见，可能有助于神经变性通过兴奋性毒性机制的背景下NeuroAIDS。
HIV-1 infected macrophages play a significant role in the neuropathogenesis of AIDS. HIV-1 viral protein R (Vpr) not only facilitates HIV-1 infection but also contribute to long-lived persistence in macrophages. Our previous studies using SILAC-based proteomic analysis showed that the expression of critical metabolic enzymes in the glycolytic pathway and tricarboxylic acid (TCA) cycle were altered in response to Vpr expression in macrophages. We hypothesized that Vpr-induced modulation of glycolysis and TCA cycle regulates glutamate metabolism and release in HIV-1 infected macrophages.We assessed the amount of specific metabolites induced by Vpr and HIV-1 in macrophages at the intracellular and extracellular level in a time-dependent manner utilizing multiple reaction monitoring (MRM) targeted metabolomics. In addition, stable isotope-labeled glucose and an MRM targeted metabolomics assay were used to evaluate the de novo synthesis and release of glutamate in Vpr overexpressing macrophages and HIV-1 infected macrophages, throughout the metabolic flux of glycolytic pathway and TCA cycle activation.The metabolic flux studies demonstrated an increase in glucose uptake, glutamate release and accumulation of -ketoglutarate (-KG) and glutamine in the extracellular milieu in Vpr expressing and HIV-1 infected macrophages. Interestingly, glutamate pools and other intracellular intermediates (glucose-6-phosphate (G6P), fructose-6-phosphate (F6P), citrate, malate, -KG, and glutamine) showed a decreased trend except for fumarate, in contrast to the glutamine accumulation observed in the extracellular space in Vpr overexpressing macrophages.Our studies demonstrate that dysregulation of mitochondrial glutamate metabolism induced by Vpr in HIV-1 infected macrophages commonly seen, may contribute to neurodegeneration via excitotoxic mechanisms in the context of NeuroAIDS.