Similar Datasets
Project description:We investigated the immediate transcriptional changes in hepatocytes following APAP-induced acute liver injury by exposing lf:UPRT zebrafish larvae to DMSO or APAP in the presence of 4TU. We the performed gene expression profiling analysis on total and nascent counts using data obtained from SLAM-ITseq of WT and Nrf2KO animals.
2024-01-13 | GSE230831 | GEO
Project description:SLAM-ITseq identifies that Nrf2 induces liver regeneration through the pentose phosphate pathway
| PRJNA962794 | ENA
Project description:SLAM-ITseq identifies that Nrf2 induces liver regeneration through the pentose phosphate pathway [Larval SLAM-Itseq]
| PRJNA962797 | ENA
Project description:A fundamental step in regeneration is rapid growth to replace lost tissue. Cells must generate sufficient lipids, nucleotides, and proteins to fuel rapid cell division. To define metabolic pathways underlying regenerative growth, we undertake a multimodal investigation of metabolic reprogramming in Xenopus tropicalis appendage regeneration. Regenerating tissues have increased glucose uptake; however, inhibition of glycolysis does not decrease regeneration. Instead, glucose is funneled to the pentose phosphate pathway (PPP), which is essential for full tail regeneration. Liquid chromatography-mass spectrometry (LC-MS) metabolite profiling reveals increased nucleotide and nicotinamide intermediates required for cell division. Using single-cell RNA sequencing (scRNA-seq), we find that highly proliferative cells have increased transcription of PPP enzymes and not glycolytic enzymes. Further, PPP inhibition results in decreased cell division specifically in regenerating tissue. Our results inform a model wherein regenerating tissues direct glucose toward the PPP, yielding nucleotide precursors to drive regenerative cell proliferation.
| S-EPMC10569227 | biostudies-literature
Project description:Given the involvement of telomerase activation and dysregulated metabolism in glioma progression, the connection between these two critical players was investigated. Pharmacological inhibition of human Telomerase reverse transcriptase (hTERT) by Costunolide induced glioma cell apoptosis in a reactive oxygen species (ROS)-dependent manner. Costunolide induced an ROS-dependent increase in p53 abrogated telomerase activity. Costunolide decreased Nrf2 level; and ectopic Nrf2 expression decreased Costunolide-induced ROS generation. While TERT knock-down abrogated Nrf2 levels, overexpression of Nrf2 increased TERT expression. Inhibition of hTERT either by Costunolide, or by siRNA or dominant-negative hTERT (DN-hTERT) abrogated (i) expression of Glucose-6-phosphate dehydrogenase (G6PD) and Transketolase (TKT) - two major nodes in the pentose phosphate (PPP) pathway; and (ii) phosphorylation of glycogen synthase (GS). hTERT knock-down decreased TKT activity and increased glycogen accumulation. Interestingly, siRNA-mediated knock-down of TKT elevated glycogen accumulation. Coherent with the in vitro findings, Costunolide reduced tumor burden in heterotypic xenograft glioma mouse model. Costunolide-treated tumors exhibited diminished TKT activity, heightened glycogen accumulation, and increased senescence. Importantly, glioblastoma multiforme (GBM) patient tumors bearing TERT promoter mutations (C228T and C250T) known to be associated with increased telomerase activity; exhibited elevated Nrf2 and TKT expression and decreased glycogen accumulation. Taken together, our findings highlight the previously unknown (i) role of telomerase in the regulation of PPP and glycogen accumulation and (ii) the involvement of Nrf2-TERT loop in maintaining oxidative defense responses in glioma cells.
| S-EPMC4917655 | biostudies-literature
Project description:Embryonic stem (ES) cells can differentiate in vitro into a variety of cell types. Efforts to produce endodermal cell derivatives, including lung, liver and pancreas, have been met with modest success. Understanding how the endoderm originates from ES cells is the first step to generate specific cell types for therapeutic purposes. Recently, it has been demonstrated that inhibition of Myc or mTOR induces endodermal differentiation. Both Myc and mTOR are known to be activators of the Pentose Phosphate Pathway (PPP). We found that, differentely from wild type (wt), ES cells unable to produce pentose sugars through PPP differentiate into endodermal precursors in cell culture conditions generally non-permissive to generate them. The same effect was observed when wt ES cells were differentiated in presence of chemical inhibitors of the PPP. These data highlight a new role for metabolism. Indeed, to our knowledge, it is the first time that modulation of a metabolic pathway is described to be crucial in determining ES cell fate.
| S-EPMC3257253 | biostudies-literature
Project description:After exposure to [U-(13)C3]glycerol, the liver produces primarily [1,2,3-(13)C3]- and [4,5,6-(13)C3]glucose in equal proportions through gluconeogenesis from the level of trioses. Other (13)C-labeling patterns occur as a consequence of alternative pathways for glucose production. The pentose phosphate pathway (PPP), metabolism in the citric acid cycle, incomplete equilibration by triose phosphate isomerase, or the transaldolase reaction all interact to produce complex (13)C-labeling patterns in exported glucose. Here, we investigated (13)C labeling in plasma glucose in rats given [U-(13)C3]glycerol under various nutritional conditions. Blood was drawn at multiple time points to extract glucose for NMR analysis. Because the transaldolase reaction and incomplete equilibrium by triose phosphate isomerase cannot break a (13)C-(13)C bond within the trioses contributing to glucose, the appearance of [1,2-(13)C2]-, [2,3-(13)C2]-, [5,6-(13)C2]-, and [4,5-(13)C2]glucose provides direct evidence for metabolism of glycerol in the citric acid cycle or the PPP but not an influence of either triose phosphate isomerase or the transaldolase reaction. In all animals, [1,2-(13)C2]glucose/[2,3-(13)C2]glucose was significantly greater than [5,6-(13)C2]glucose/[4,5-(13)C2]glucose, a relationship that can only arise from gluconeogenesis followed by passage of substrates through the PPP. In summary, the hepatic PPP in vivo can be detected by (13)C distribution in blood glucose after [U-(13)C3]glycerol administration.
| S-EPMC4239613 | biostudies-literature
Project description:Due to its role in maintaining the proper functioning of the cell, the pentose phosphate pathway (PPP) is one of the most important metabolic pathways. It is responsible for regulating the concentration of simple sugars and provides precursors for the synthesis of amino acids and nucleotides. In addition, it plays a critical role in maintaining an adequate level of NADPH, which is necessary for the cell to fight oxidative stress. These reasons prompted the authors to develop a computational model, based on queueing theory, capable of simulating changes in PPP metabolites' concentrations. The model has been validated with empirical data from tumor cells. The obtained results prove the stability and accuracy of the model. By applying queueing theory, this model can be further expanded to include successive metabolic pathways. The use of the model may accelerate research on new drugs, reduce drug costs, and reduce the reliance on laboratory animals necessary for this type of research on which new methods are tested.
| S-EPMC8930976 | biostudies-literature
Project description:This article describes the first patient with a deficiency of transaldolase (TALDO1 [E.C.2.2.1.2]). Clinically, the patient presented with liver cirrhosis and hepatosplenomegaly during early infancy. In urine and plasma, elevated concentrations of ribitol, D-arabitol, and erythritol were found. By incubating the patient's lymphoblasts and erythrocytes with ribose-5-phosphate and subsequently analyzing phosphate sugar metabolites, we discovered a deficiency of transaldolase. Sequence analysis of the transaldolase gene from this patient showed a homozygous deletion of 3 bp. This deletion results in absence of serine at position 171 of the transaldolase protein. This amino acid is invariable between species and is located in a conserved region, indicating its importance for enzyme activity. The detection of this new inborn error of pentose metabolism has implications for the diagnostic workup of liver problems of unknown etiology.
| S-EPMC1226089 | biostudies-literature
Project description:Keratin 6A (KRT6A) belongs to the keratin protein family which is a critical component of cytoskeleton in mammalian cells. Although KRT6A upregulation in non-small cell lung cancer (NSCLC) has been reported, the regulatory mechanism and functional role of KRT6A in NSCLC development have been less well investigated. In this study, KRT6A was confirmed to be highly expressed in NSCLC tissue samples, and its high expression correlated with poor patient prognosis. Furthermore, overexpression of KRT6A promotes NSCLC cell proliferation and invasion. Mechanistically, KRT6A overexpression is sufficient to upregulate glucose-6-phosphate dehydrogenase (G6PD) levels and increase the pentose phosphate pathway flux, an essential metabolic pathway to support cancer cell growth and invasion. In addition, we discovered that lysine-specific demethylase 1A (LSD1) functions upstream to promote KRT6A gene expression. We also found that the MYC family members c-MYC/MYCN are involved in KRT6A-induced G6PD upregulation. Therefore, this study reveals an underappreciated mechanism that KRT6A acts downstream of LSD1 and functions as a pivotal driver for NSCLC progression by upregulating G6PD through the MYC signaling pathway. Together, KRT6A and LSD1 may serve as potential prognostic indictors and therapeutic targets for NSCLC.
| S-EPMC8255478 | biostudies-literature