nucleotide synthesis
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Author(s):  
Saniya Sahar

Abstract: Pregnancy represents a period of fast tissue growth of maternal and foetal tissues that's related to enhanced energy and nutrient needs. Maternal nutrition throughout gestation period, has being essential for best offspring development, reducing long unwellness burden and for general health throughout life. Maternal Folate throughout pregnancy might have numerous roles in offspring health, as well as neurodevelopment and psychological feature performance in childhood. Folate is crucial for C1 metabolism, a network of pathways concerned in many biological processes as well as nucleotide synthesis, deoxyribonucleic acid repair and methylation reactions. The periconceptional use of pteroylglutamic acid (Folic Acid ) containing supplements reduces the primary incidence, as well as recurrence of neural tube defects. Folic Acid (FA) are artificial form of a necessary vitamin generically considered Folates or B9. It is concerned in one-carbon metabolism, and it's been connected to lowering neural tube Defect (NTD). National programs to mandate fortification of food with Folic Acid have reduced the prevalence of NTDs worldwide . The indisputable protecting role of Folic Acid in the hindrance of NTD, in addition to the low compliance of women to Folic Acid recommendations, has aroused the choice of mandatory Folic Acid fortification, a policy currently in place in over eighty countries worldwide. Mandatory food fortification needs food makers to feature Folic Acid to certain foods (e.g. starch or grain products), whereas voluntary fortification permits Folic Acid to be added to foods at the discretion of manufacturers. Food fortification with Folic Acid because the intervention is likely to achieve increasing Folic Acid intake among populations throughout the world. The objective of this article is to discuss the Role of Folic Acid and Folate during pregnancy and to review the role of Folate and Folic Acid , metabolism , absorption and Folic Acid effects on maternal on the basis of recent findings that are important for implementation of fortified food to design future studies. Keywords: Neurodevelopment, Methylation Reactions, Pteroylglutamic Acid, Bioavailability, Monoglutamates.


2021 ◽  
Author(s):  
Ning Chen ◽  
Hao Zhang ◽  
En Zang ◽  
Zhi-Xia Liu ◽  
Ya-Fei Lan ◽  
...  

Abstract Opisthopappus is a major wild source of Asteraceae with good cold and drought resistance. Two species of this genus (Opisthopappus taihangensis and Opisthopappus longilobus) have been employed as model systems to address the evolutionary history of perennial herb biomes in the Taihang Mountains of China. However, further studies on the adaptive divergence processes of these two species are currently impeded by the lack of genomic resources. To elucidate the molecular mechanisms involved, a comparative analysis of these two species was conducted. Among the identified transcription factors, the bHLH members were most prevalent, which exhibited significantly different expression levels in the terpenoid metabolic pathway. O. longilobus revealed a higher expression than did O. taihangensis in terms of terpenes biosynthesis and metabolism, particularly regarding monoterpenoids and diterpenoids. Analyses of the positive selection genes (PSGs) identified from O. taihangensis and O. longilobus, 1203 genes were found that related to adaptative divergence, which were under rapid evolution and/or have signs of positive selection. Different PSG expressions occurred primarily in the mitochondrial electron transport, starch degradation, secondary metabolism, as well as nucleotide synthesis and S-metabolism pathway processes. Two PSGs were obviously differentially expressed in terpenes biosynthesis that might result in the fragrances divergence between O. longilobus and O. taihangensis, which would provide insights as to how the two species adapted to different environments, characterized by sub-humid warm temperate and temperate continental monsoon climates. The comparative analysis for these two species of Opisthopappus not only revealed how the divergence occurred from molecular perspective, but also provided novel insights into how differential adaptations occurred in Taihang Mountains.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
David Sokolov ◽  
Emily R Sechrest ◽  
Yekai Wang ◽  
Connor Nevin ◽  
Jianhai Du ◽  
...  

Despite mounting evidence that the mammalian retina is exceptionally reliant on proper NAD+ homeostasis for health and function, the specific roles of subcellular NAD+ pools in retinal development, maintenance, and disease remain obscure. Here, we show that deletion of the nuclear-localized NAD+ synthase nicotinamide mononucleotide adenylyltransferase-1 (NMNAT1) in the developing murine retina causes early and severe degeneration of photoreceptors and select inner retinal neurons via multiple distinct cell death pathways. This severe phenotype is associated with disruptions to retinal central carbon metabolism, purine nucleotide synthesis, and amino acid pathways. Furthermore, transcriptomic and immunostaining approaches reveal dysregulation of a collection of photoreceptor and synapse-specific genes in NMNAT1 knockout retinas prior to detectable morphological or metabolic alterations. Collectively, our study reveals previously unrecognized complexity in NMNAT1-associated retinal degeneration and suggests a yet-undescribed role for NMNAT1 in gene regulation during photoreceptor terminal differentiation.


2021 ◽  
Author(s):  
Diana D. Shi ◽  
Milan R. Savani ◽  
Michael M. Levitt ◽  
Adam C. Wang ◽  
Jennifer E. Endress ◽  
...  

Mutations affecting isocitrate dehydrogenase (IDH) enzymes are prevalent in glioma, leukemia, and other cancers. Although mutant IDH inhibitors are effective against leukemia, they appear less active in aggressive glioma, underscoring the need for alternative treatment strategies. Through a chemical synthetic lethality screen, we discovered that IDH1 mutant glioma cells are hypersensitive to drugs targeting enzymes in the de novo pyrimidine nucleotide synthesis pathway, including dihydroorotate dehydrogenase (DHODH). We developed a genetically engineered mouse model of mutant IDH1-driven astrocytoma and used it and multiple patient-derived models to show that the brain-penetrant DHODH inhibitor BAY 2402234 displays monotherapy efficacy against IDH mutant gliomas. Mechanistically, this vulnerability selectively applies to de novo pyrimidine, but not purine, synthesis because glioma cells engage disparate programs to produce these nucleotide species and because IDH oncogenes increase DNA damage upon nucleotide pool imbalance. Our work outlines a tumor-selective, biomarker-guided therapeutic strategy that is poised for clinical translation.


Chemotherapy ◽  
2021 ◽  
pp. 1-13
Author(s):  
Noorhan Ghanem ◽  
Chirine El-Baba ◽  
Khaled Araji ◽  
Riyad El-Khoury ◽  
Julnar Usta ◽  
...  

<b><i>Background:</i></b> Tumorigenesis is associated with deregulation of nutritional requirements, intermediary metabolites production, and microenvironment interactions. Unlike their normal cell counterparts, tumor cells rely on aerobic glycolysis, through the Warburg effect. <b><i>Summary:</i></b> The pentose phosphate pathway (PPP) is a major glucose metabolic shunt that is upregulated in cancer cells. The PPP comprises an oxidative and a nonoxidative phase and is essential for nucleotide synthesis of rapidly dividing cells. The PPP also generates nicotinamide adenine dinucleotide phosphate, which is required for reductive metabolism and to counteract oxidative stress in tumor cells. This article reviews the regulation of the PPP and discusses inhibitors that target its main pathways. <b><i>Key Message:</i></b> Exploiting the metabolic vulnerability of the PPP offers potential novel therapeutic opportunities and improves patients’ response to cancer therapy.


Biomolecules ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1666
Author(s):  
Iiro Taneli Helenius ◽  
Hanumantha Rao Madala ◽  
Jing-Ruey Joanna Yeh

A better understanding of the metabolic constraints of a tumor may lead to more effective anticancer treatments. Evidence has emerged in recent years shedding light on a crucial aspartate dependency of many tumor types. As a precursor for nucleotide synthesis, aspartate is indispensable for cell proliferation. Moreover, the malate–aspartate shuttle plays a key role in redox balance, and a deficit in aspartate can lead to oxidative stress. It is now recognized that aspartate biosynthesis is largely governed by mitochondrial metabolism, including respiration and glutaminolysis in cancer cells. Therefore, under conditions that suppress mitochondrial metabolism, including mutations, hypoxia, or chemical inhibitors, aspartate can become a limiting factor for tumor growth and cancer cell survival. Notably, aspartate availability has been associated with sensitivity or resistance to various therapeutics that are presently in the clinic or in clinical trials, arguing for a critical need for more effective aspartate-targeting approaches. In this review, we present current knowledge of the metabolic roles of aspartate in cancer cells and describe how cancer cells maintain aspartate levels under different metabolic states. We also highlight several promising aspartate level-modulating agents that are currently under investigation.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2249-2249
Author(s):  
Sujan Piya ◽  
Huaxian Ma ◽  
Priyanka Sharma ◽  
Kensuke Kojima ◽  
Vivian Ruvolo ◽  
...  

Abstract Background: De novo nucleotide synthesis is necessary to meet the enormous demand for nucleotides, other macromolecules associated with acute myeloid leukemia (AML) progression 1, 2, 3 4. Hence, we hypothesized that targeting de novo nucleotide synthesis would lead to the depletion of the nucleotide pool, pyrimidine starvation and increase oxidative stress preferentially in leukemic cells compared to their non-malignant counterparts, impacting proliferative and differentiation pathways. Emvododstat (PTC299) is an inhibitor of dihydroorotate dehydrogenase (DHODH), a rate-limiting enzyme for de novo pyrimidine nucleotide synthesis that is currently in a clinical trial for the treatment of AML. Objectives: The goals of these studies were to understand the emvododstat-mediated effects on leukemia growth, differentiation and impact on Leukemia Stem Cells(LSCs). Comprehensive analyses of mitochondrial function, metabolic signaling in PI3K/AKT pathways, apoptotic signatures, and DNA damage responses were carried out. The rationale for clinical testing emvododstat was confirmed in an AML-PDX model. Results: Emvododstat treatment in cytarabine-resistant AML cells and primary AML blasts induced apoptosis, differentiation, and reduced proliferation, with corresponding decreased in cell number and increases in annexin V- and CD14-positive cells. Indeed, the inhibition of de novo nucleotide synthesis compromises the dynamic metabolic landscape and mitochondrial function, as indicated by alterations in the oxygen consumption rate (OCR) and mitochondrial ROS/membrane potential and corresponding differentiation, apoptosis, and/or inhibition of proliferation of LSCs. These effects can be reversed by the addition of exogenous uridine and orotate. Further immunoblotting and mass cytometry (CyTOF) analyses demonstrated changes in apoptotic and cell signaling proteins (cleaved PARP, cleaved caspase-3) and DNA damage responses (TP53, γH2AX) and PI3/AKT pathway downregulation in response to emvododstat. Importantly, emvododstat treatment reduced leukemic cell burden in a mouse model of AML PDX ( Complex karyotype ,mutation in ASXL1, IDH2, NRAS), decreased levels of leukemia stem cells frequency (1 in 522,460 Vs 1 in 3,623,599 in vehicle vs emvododstat treated mice), and improved survival. The median survival 40 days vs. 30 days, P=0.0002 in primary transplantation and 36 days vs 53.5 days, P=0.005 in secondary transpantation in a PDX mouse model of human AML. This corresponded with a reduction in the bone marrow burden of leukemia and increased expression of differentiation markers in mice treated with emvododstat (Fig. 1). These data demonstrate effect of emvododstat on mitochondrial functions . Conclusion: Inhibition of de novo pyrimidine synthesis triggers differentiation, apoptosis, and depletes LSCs in AML models. Emvododstat is a novel dihydroorotate dehydrogenase inhibitor being tested in a clinical trial for the treatment of myeloid malignancies and COVID-19. Keywords: AML, emvododstat, DHODH, apoptosis, differentiation References: 1 Thomas, D. & Majeti, R. Biology and relevance of human acute myeloid leukemia stem cells. Blood 129, 1577-1585, doi:10.1182/blood-2016-10-696054 (2017). 2 Quek, L. et al. Genetically distinct leukemic stem cells in human CD34- acute myeloid leukemia are arrested at a hemopoietic precursor-like stage. The Journal of experimental medicine 213, 1513-1535, doi:10.1084/jem.20151775 (2016). 3 Villa, E., Ali, E. S., Sahu, U. & Ben-Sahra, I. Cancer Cells Tune the Signaling Pathways to Empower de Novo Synthesis of Nucleotides. Cancers (Basel) 11, doi:10.3390/cancers11050688 (2019). 4 DeBerardinis, R. J. & Chandel, N. S. Fundamentals of cancer metabolism. Sci Adv 2, e1600200, doi:10.1126/sciadv.1600200 (2016). Figure 1 Figure 1. Disclosures Weetall: PTC therapeutics: Current Employment. Sheedy: PTC therapeutics: Current Employment. Ray: PTC therapeutics: Current Employment. Andreeff: Karyopharm: Research Funding; AstraZeneca: Research Funding; Oxford Biomedica UK: Research Funding; Aptose: Consultancy; Daiichi-Sankyo: Consultancy, Research Funding; Syndax: Consultancy; Breast Cancer Research Foundation: Research Funding; Reata, Aptose, Eutropics, SentiBio; Chimerix, Oncolyze: Current holder of individual stocks in a privately-held company; Novartis, Cancer UK; Leukemia & Lymphoma Society (LLS), German Research Council; NCI-RDCRN (Rare Disease Clin Network), CLL Foundation; Novartis: Membership on an entity's Board of Directors or advisory committees; Senti-Bio: Consultancy; Medicxi: Consultancy; ONO Pharmaceuticals: Research Funding; Amgen: Research Funding; Glycomimetics: Consultancy. Borthakur: ArgenX: Membership on an entity's Board of Directors or advisory committees; Protagonist: Consultancy; Astex: Research Funding; University of Texas MD Anderson Cancer Center: Current Employment; Ryvu: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy.


Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2439
Author(s):  
Yuhui Yang ◽  
Jing Qian ◽  
Bowen Li ◽  
Manman Lu ◽  
Guowei Le ◽  
...  

Methionine restriction (MR) has been reported to have many beneficial health effects, including stress resistance enhancement and lifespan extension. However, the effects of MR on the splenic metabolic dysfunction induced by obesity in mice remain unknown. This study aimed to investigate the scientific problem and clarify its possible mechanisms. C57BL/6J mice in the control group were fed a control diet (0.86% methionine, 4.2% fat) for 34 weeks, and others were fed a high-fat diet (0.86% methionine, 24% fat) for 10 weeks to establish diet-induced obese (DIO) mouse models. Then, the obtained DIO mice were randomly divided into two groups: the DIO group (DIO diet), the DIO + MR group (0.17% methionine, 24% fat) for 24 weeks. Our results indicated that MR decreased spleen weight, and spleen and plasma lipid profiles, promoted lipid catabolism and fatty acid oxidation, glycolysis and tricarboxylic acid cycle metabolism, and improved mitochondrial function and ATP generation in the spleen. Moreover, MR normalized the splenic redox state and inflammation-related metabolite levels, and increased plasma levels of immunoglobulins. Furthermore, MR increased percent lean mass and splenic crude protein levels, activated the autophagy pathway and elevated nucleotide synthesis to maintain protein synthesis in the spleen. These findings indicate that MR can ameliorate metabolic dysfunction by reducing lipid accumulation, oxidative stress, and inflammation in the spleen, and the mechanism may be the activation of autophagy pathway.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Irini Skaripa-Koukelli ◽  
David Hauton ◽  
John Walsby-Tickle ◽  
Eloïse Thomas ◽  
Joshua Owen ◽  
...  

Abstract Background Triple negative breast cancer (TNBC) poses a serious clinical challenge as it is an aggressive form of the disease that lacks estrogen receptor, progesterone receptor, and ERBB2 (formerly HER2) gene amplification, which limits the treatment options. The Warburg phenotype of upregulated glycolysis in the presence of oxygen has been shown to be prevalent in TNBC. Elevated glycolysis satisfies the energy requirements of cancer cells, contributes to resistance to treatment by maintaining redox homeostasis and generating nucleotide precursors required for cell proliferation and DNA repair. Expression of the monocarboxylate transporter 1 (MCT1), which is responsible for the bidirectional transport of lactate, correlates with an aggressive phenotype and poor outcome in several cancer types, including breast cancer. In this study, 3-bromopyruvate (3BP), a lactate/pyruvate analog, was used to selectively target TNBC cells that express MCT1. Methods The cytotoxicity of 3BP was tested in MTT assays using human TNBC cell lines: BT20 (MCT1+/MCT4−), MDA-MB-23 (MCT1−/MCT4+), and BT20 in which MCT1 was knocked down (siMCT1-BT20). The metabolite profile of 3BP-treated and 3BP-untreated cells was investigated using LC-MS/MS. The extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) of BT20 and MDA-MB-231 cells treated with 3BP were measured using a Seahorse XF96 extracellular flux analyzer. The impact of ionizing radiation on cell survival, alone or in combination with 3BP pre-treatment, was evaluated using clonogenic assays. Results Metabolomic analyses showed that 3BP causes inhibition of glycolysis, disturbance of redox homeostasis, decreased nucleotide synthesis, and was accompanied by a reduction in medium acidification. In addition, 3BP potentiated the cytotoxic effect of ionizing radiation, a treatment that is frequently used in the management of TNBC. Conclusions Overall, MCT1-mediated metabolic perturbation in combination with radiotherapy is shown to be a promising strategy for the treatment of glycolytic tumors such as TNBC, overcoming the selectivity challenges of targeting glycolysis with glucose analogs.


Cancers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 5058
Author(s):  
Marcella Bonanomi ◽  
Noemi Salmistraro ◽  
Giulia Fiscon ◽  
Federica Conte ◽  
Paola Paci ◽  
...  

Rewiring glucose metabolism toward aerobic glycolysis provides cancer cells with a rapid generation of pyruvate, ATP, and NADH, while pyruvate oxidation to lactate guarantees refueling of oxidized NAD+ to sustain glycolysis. CtPB2, an NADH-dependent transcriptional co-regulator, has been proposed to work as an NADH sensor, linking metabolism to epigenetic transcriptional reprogramming. By integrating metabolomics and transcriptomics in a triple-negative human breast cancer cell line, we show that genetic and pharmacological down-regulation of CtBP2 strongly reduces cell proliferation by modulating the redox balance, nucleotide synthesis, ROS generation, and scavenging. Our data highlight the critical role of NADH in controlling the oncogene-dependent crosstalk between metabolism and the epigenetically mediated transcriptional program that sustains energetic and anabolic demands in cancer cells.


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