scholarly journals Optimization of NAMPT (Nicotinamide Phosphoribosyltransferase) Activators: Discovery of N,N-Diethyl-1,2-benzoxazole-3-carboxamide Derivatives as Potent NAMPT Activators with Mitigated Mutagenic Risks

Heterocycles ◽  
2022 ◽  
Vol 104 (1) ◽  
pp. 94
Author(s):  
Mayuko Akiu ◽  
Takashi Tsuji ◽  
Yoshitaka Sogawa ◽  
Koji Terayama ◽  
Mika Yokoyama ◽  
...  
Keyword(s):  
Nicotinamide Phosphoribosyltransferase

scholarly journals TAMI-08. A TALE OF TWO TELOMERE MAINTENANCE MECHANISMS: TERT EXPRESSION AND THE ALT PATHWAY INDUCE UNIQUE MRS-DETECTABLE METABOLIC REPROGRAMMING IN LOW-GRADE GLIOMAS

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii214-ii214
Author(s):  
Pavithra Viswanath ◽  
Georgios Batsios ◽  
Anne Marie Gillespie ◽  
Hema Artee Luchman ◽  
Joseph Costello ◽  
...  
Keyword(s):  
Treatment Response ◽  
Metabolic Reprogramming ◽  
Telomere Maintenance ◽  
Imaging Biomarker ◽  
Low Grade ◽  
Tumor Proliferation ◽  
Nicotinamide Phosphoribosyltransferase ◽  
Non Invasive ◽  
Key Enzyme ◽  
Tert Expression

Abstract Telomeres are nucleoprotein structures at chromosomal ends that shorten with cell division and constitute a natural barrier to proliferation. In order to proliferate indefinitely, all tumors require a telomere maintenance mechanism (TMM). Telomerase reverse transcriptase (TERT) expression is the TMM in most tumors, including low-grade oligodendrogliomas (LGOGs). In contrast, low-grade astrocytomas (LGAs) use the alternative lengthening of telomeres (ALT) pathway as their TMM. As molecular hallmarks of tumor proliferation, TMMs are attractive tumor biomarkers and therapeutic targets. Non-invasive imaging of TMM status will, therefore, allow assessment of tumor proliferation and treatment response. However, translational methods of imaging TMM status are lacking. Here, we show that TERT expression and the ALT pathway are associated with unique magnetic resonance spectroscopy (MRS)-detectable metabolic reprogramming in LGOGs and LGAs respectively. In genetically-engineered and patient-derived LGOG models, TERT expression is linked to elevated 1H-MRS-detectable NAD(P)/H, glutathione, aspartate and AXP. In contrast, the ALT pathway in LGAs is associated with higher α-ketoglutarate, glutamate, alanine and AXP. Importantly, elevated flux of hyperpolarized [1-13C]-alanine to pyruvate, which depends on α-ketoglutarate, is a non-invasive in vivo imaging biomarker of the ALT pathway in LGAs while elevated flux of hyperpolarized [1-13C]-alanine to lactate, which depends on NADH, is an imaging biomarker of TERT expression in LGOGs. Mechanistically, the ALT pathway in LGAs is linked to higher glutaminase (GLS), a key enzyme for α-ketoglutarate biosynthesis while TERT expression in LGOGs is associated with elevated nicotinamide phosphoribosyltransferase (NAMPT), a key enzyme for NADH biosynthesis. Notably, TERT expression and the ALT pathway are linked to MRS-detectable metabolic reprogramming in LGOG and LGA patient biopsies, emphasizing the clinical validity of our observations. Collectively, we have identified unique metabolic signatures of TMM status that integrate critical oncogenic information with noninvasive imaging modalities that can improve diagnosis and treatment response monitoring for LGOG and LGA patients.

Nicotinamide phosphoribosyltransferase inhibitors selectively induce apoptosis of AML stem cells by disrupting lipid homeostasis

2021 ◽  
Author(s):  
Amit Subedi ◽  
Qiang Liu ◽  
Dhanoop M. Ayyathan ◽  
David Sharon ◽  
Severine Cathelin ◽  
...  
Keyword(s):  
Stem Cells ◽  
Lipid Homeostasis ◽  
Nicotinamide Phosphoribosyltransferase

DDRE-27. METABOLIC SWITCHING AS A MECHANISM OF DRUG RESISTANCE AGAINST NAMPT INHIBITION IN GLIOMAS

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi80-vi80
Author(s):  
Pratibha Sharma ◽  
Vinay Puduvalli
Keyword(s):  
Drug Resistance ◽  
Energy Metabolism ◽  
Cross Reactivity ◽  
Alternative Methods ◽  
Cross Resistance ◽  
Significant Heterogeneity ◽  
Drug Resistant ◽  
High Accumulation ◽  
Metabolic Switch ◽  
Nicotinamide Phosphoribosyltransferase

Abstract BACKGROUND Gliomas exhibit significant heterogeneity in treatment response and characteristically deploy resistance mechanisms that render conventional therapies ineffective. Recently, novel agents have been developed that target regulators of differential energy pathways specifically utilized by gliomas. We previously reported on the targeting of Nicotinamide Phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of the NAD+ salvage pathway and its essential role in glioma cell energy metabolism. Here, we determined the mechanisms by which glioma cells bypass blockade of energy metabolism and develop resistance to NAMPT inhibitors. METHODS Using isogenic parental and drug-resistant patient-derived glioma stem-like cells (GSCs), we examined adaptive changes after NAMPT inhibition in glycolysis, mitochondrial function (oxidative state, basal respiration rate, spare respiratory capacity, maximum respiration capacity and proton leak) and metabolite levels using Agilent Seahorse assay and targeted metabolomics. Cross reactivity across various NAMPT inhibitors was measured using Cell Titer Glo assay. RESULTS GSCs exposed for an extended period to sub-lethal doses of FK866, a potent NAMPT inhibitor, acquired drug resistance to the agent which were also cross-resistant to other NAMPT inhibitors. Drug-resistant GSCs showed a decrease in extracellular acidification rate and oxygen consumption rate compared to isogenic parental lines. Further, metabolomic analysis showed a high accumulation of glutamate, creatine and histidine metabolites in these cells. These results indicate a shift in metabolism of drug-resistant GSCs from carbon metabolism to nitrogen metabolism. CONCLUSIONS GSCs resistant to the NAMPT inhibitor, FK866 showed cross resistance to other NAMPT inhibitors indicating specificity of this effect. The resistance mechanism involves a shift of preferential energy generation from glycolysis to amino acid metabolism which allows the cells to use alternative methods to generate NAD. Additional results from ongoing studies to delineate the mechanisms of metabolic switch in the drug resistance lines will be presented that will help develop strategies to combat resistance to NAMPT inhibitors.

scholarly journals Extracellular nicotinamide phosphoribosyltransferase (eNAMPT) is a novel marker for patients with BRAF-mutated metastatic melanoma

Oncotarget ◽  
2018 ◽  
Vol 9 (27) ◽  
pp. 18997-19005 ◽  
Author(s):  
Valentina Audrito ◽  
Antonella Managò ◽  
Federica Zamporlini ◽  
Eliana Rulli ◽  
Federica Gaudino ◽  
...  
Keyword(s):  
Metastatic Melanoma ◽  
Nicotinamide Phosphoribosyltransferase

scholarly journals AB1326 Nicotinamide phosphoribosyltransferase may be new factors contributing to osteoarthritis

2018 ◽  
Author(s):  
L. Sivordova ◽  
J. Polyakova ◽  
Y. Akhverdyan ◽  
V. Kravtsov ◽  
N. Fofanova ◽  
...  
Keyword(s):  
Nicotinamide Phosphoribosyltransferase

scholarly journals Imeglimin Amplifies Glucose-Stimulated Insulin Release from Diabetic Islets via a Distinct Mechanism of Action

2020 ◽  
Author(s):  
Sophie Hallakou-Bozec ◽  
Micheline Kergoat ◽  
Pascale Fouqueray ◽  
Sébastien Bolze ◽  
David E. Moller
Keyword(s):  
Type 2 Diabetes ◽  
Mode Of Action ◽  
Cell Function ◽  
Drug Candidate ◽  
Β Cell ◽  
Nicotinamide Phosphoribosyltransferase ◽  
Predominant Component ◽  
Cyclic Adp Ribose ◽  
Β Cell Function

ABSTRACTPancreatic islet β-cell dysfunction is characterized by defective glucose-stimulated insulin secretion (GSIS) and is a predominant component of the pathophysiology of diabetes. Imeglimin, a novel first-in-class small molecule tetrahydrotriazine drug candidate, improves glycemia and GSIS in preclinical models and clinical trials in patients with type 2 diabetes; however, the mechanism by which it restores β-cell function is unknown. Here, we show that Imeglimin acutely and directly amplifies GSIS in islets isolated from rodents with Type 2 diabetes via a mode of action that is distinct from other known therapeutic approaches. The underlying mechanism involves increases in the cellular nicotinamide adenine dinucleotide (NAD+) pool – potentially via the salvage pathway and induction of nicotinamide phosphoribosyltransferase (NAMPT) along with augmentation of glucose-induced ATP levels. Further, additional results suggest that NAD+ conversion to a second messenger, cyclic ADP ribose (cADPR), via cyclic ADP ribose hydrolase (CD38) is required for Imeglimin’s effects in islets, thus representing a potential link between increased NAD+ and enhanced glucose-induced Ca2+ mobilization which - in turn - is known to drive insulin granule exocytosis. Collectively, these findings implicate a novel mode of action for Imeglimin that explains its ability to effectively restore β-cell function and provides for a new approach to treat patients suffering from Type 2 diabetes.

scholarly journals Nicotinamide phosphoribosyltransferase postpones rat bone marrow mesenchymal stem cell senescence by mediating NAD+–Sirt1 signaling

Aging ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 3505-3522 ◽  
Author(s):  
Chenchen Pi ◽  
Yue Yang ◽  
Yanan Sun ◽  
Huan Wang ◽  
Hui Sun ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
Mesenchymal Stem Cell ◽  
Cell Senescence ◽  
Nicotinamide Phosphoribosyltransferase ◽  
Rat Bone

scholarly journals Metabolic tracing reveals novel adaptations to skeletal muscle cell energy production pathways in response to NAD+ depletion

2019 ◽  
Vol 3 ◽  
pp. 147 ◽  
Author(s):  
Lucy A. Oakey ◽  
Rachel S. Fletcher ◽  
Yasir S. Elhassan ◽  
David M. Cartwright ◽  
Craig L. Doig ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Carbon Metabolism ◽  
Energy Production ◽  
Quantum Coherence ◽  
Metabolic Energy ◽  
Whole Body ◽  
Muscle Physiology ◽  
Nicotinamide Phosphoribosyltransferase ◽  
Central Carbon ◽  
Metabolic Tracing

Background: Skeletal muscle is central to whole body metabolic homeostasis, with age and disease impairing its ability to function appropriately to maintain health. Inadequate NAD+ availability is proposed to contribute to pathophysiology by impairing metabolic energy pathway use. Despite the importance of NAD+ as a vital redox cofactor in energy production pathways being well-established, the wider impact of disrupted NAD+ homeostasis on these pathways is unknown. Methods: We utilised skeletal muscle myotube models to induce NAD+ depletion, repletion and excess and conducted metabolic tracing to provide comprehensive and detailed analysis of the consequences of altered NAD+ metabolism on central carbon metabolic pathways. We used stable isotope tracers, [1,2-13C] D-glucose and [U-13C] glutamine, and conducted combined 2D-1H,13C-heteronuclear single quantum coherence (HSQC) NMR spectroscopy and GC-MS analysis. Results: NAD+ excess driven by nicotinamide riboside (NR) supplementation within skeletal muscle cells resulted in enhanced nicotinamide clearance, but had no effect on energy homeostasis or central carbon metabolism. Nicotinamide phosphoribosyltransferase (NAMPT) inhibition induced NAD+ depletion and resulted in equilibration of metabolites upstream of glyceraldehyde phosphate dehydrogenase (GAPDH). Aspartate production through glycolysis and TCA cycle activity was increased in response to low NAD+, which was rapidly reversed with repletion of the NAD+ pool using NR. NAD+ depletion reversibly inhibits cytosolic GAPDH activity, but retains mitochondrial oxidative metabolism, suggesting differential effects of this treatment on sub-cellular pyridine pools. When supplemented, NR efficiently reversed these metabolic consequences. However, the functional relevance of increased aspartate levels after NAD+ depletion remains unclear, and requires further investigation. Conclusions: These data highlight the need to consider carbon metabolism and clearance pathways when investigating NAD+ precursor usage in models of skeletal muscle physiology.

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