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Bioorganic & Medicinal Chemistry Letters Oct 2021Two distinct diazo precursors, imidazotetrazine and nitrous amide, were explored as promoieties in designing prodrugs of 6-diazo-5-oxo-l-norleucine (DON), a glutamine...
Two distinct diazo precursors, imidazotetrazine and nitrous amide, were explored as promoieties in designing prodrugs of 6-diazo-5-oxo-l-norleucine (DON), a glutamine antagonist. As a model for an imidazotetrazine-based prodrug, we synthesized (S)-2-acetamido-6-(8-carbamoyl-4-oxoimidazo[5,1-d][1,2,3,5]tetrazin-3(4H)-yl)-5-oxohexanoic acid (4) containing the entire scaffold of temozolomide, a precursor of the DNA-methylating agent clinically approved for the treatment of glioblastoma multiforme. For a nitrous amide-based prodrug, we synthesized 2-acetamido-6-(((benzyloxy)carbonyl)(nitroso)amino)-5-oxohexanoic acid (5) containing a N-nitrosocarbamate group, which can be converted to a diazo moiety via a mechanism similar to that of streptozotocin, a clinically approved diazomethane-releasing drug containing an N-nitrosourea group. Preliminary characterization confirmed formation of N-acetyl DON (6), also known as duazomycin A, from compound 4 in a pH-dependent manner while compound 5 did not exhibit sufficient stability to allow further characterization. Taken together, our model studies suggest that further improvements are needed to translate this prodrug approach into glutamine antagonist-based therapy.
Topics: Diazooxonorleucine; Drug Design; Drug Stability; Glutamine; Molecular Structure; Prodrugs
PubMed: 34400301
DOI: 10.1016/j.bmcl.2021.128321 -
International Journal of Molecular... May 2021Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to the development of atherosclerosis and restenosis. Glycolysis and...
Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to the development of atherosclerosis and restenosis. Glycolysis and glutaminolysis are increased in rapidly proliferating VSMCs to support their increased energy requirements and biomass production. Thus, it is essential to develop new pharmacological tools that regulate metabolic reprogramming in VSMCs for treatment of atherosclerosis. The effects of 6-diazo-5-oxo-L-norleucine (DON), a glutamine antagonist, have been broadly investigated in highly proliferative cells; however, it is unclear whether DON inhibits proliferation of VSMCs and neointima formation. Here, we investigated the effects of DON on neointima formation in vivo as well as proliferation and migration of VSMCs in vitro. DON simultaneously inhibited FBS- or PDGF-stimulated glycolysis and glutaminolysis as well as mammalian target of rapamycin complex I activity in growth factor-stimulated VSMCs, and thereby suppressed their proliferation and migration. Furthermore, a DON-derived prodrug, named JHU-083, significantly attenuated carotid artery ligation-induced neointima formation in mice. Our results suggest that treatment with a glutamine antagonist is a promising approach to prevent progression of atherosclerosis and restenosis.
Topics: Animals; Antimetabolites, Antineoplastic; Cell Cycle; Cell Movement; Cell Proliferation; Cells, Cultured; Diazooxonorleucine; Glutamine; Glycolysis; Immunohistochemistry; Male; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, Inbred C57BL; Mitochondria; Muscle, Smooth, Vascular; Neointima; Oxidative Phosphorylation; Platelet-Derived Growth Factor; Rats; Rats, Sprague-Dawley; Serum Albumin, Bovine
PubMed: 34070527
DOI: 10.3390/ijms22115602 -
Clinical & Translational Oncology :... Nov 2021Glutamine metabolism is one of the hallmarks of cancers which is described as an essential role in serving as a major energy and building blocks supply to cell... (Review)
Review
Glutamine metabolism is one of the hallmarks of cancers which is described as an essential role in serving as a major energy and building blocks supply to cell proliferation in cancer cells. Many malignant tumor cells always display glutamine addiction. The "kidney-type" glutaminase (GLS1) is a metabolism enzyme which plays a significant part in glutaminolysis. Interestingly, GLS1 is often overexpressed in highly proliferative cancer cells to fulfill enhanced glutamine demand. So far, GLS1 has been proved to be a significant target during the carcinogenesis process, and emerging evidence reveals that its inhibitors could provide a benefit strategy for cancer therapy. Herein, we summarize the prognostic value of GLS1 in multiple cancer type and its related regulatory factors which are associated with antitumor activity. Moreover, this review article highlights the remarkable reform of discovery and development for GLS1 inhibitors. On the basis of case studies, our perspectives for targeting GLS1 and development of GLS1 antagonist are discussed in the final part.
Topics: Apoptosis; Benzophenanthridines; Cell Proliferation; Diazooxonorleucine; Disease Progression; Drug Resistance, Neoplasm; Genes, myc; Glutaminase; Glutamine; Humans; MicroRNAs; NF-kappa B; Neoplasm Proteins; Neoplasms; Oxidation-Reduction; Phosphates; Prognosis; Retinoblastoma Protein; Sulfides; Thiadiazoles
PubMed: 34023970
DOI: 10.1007/s12094-021-02645-2 -
Biochemical and Biophysical Research... Jun 2021Myocardial ischemia/reperfusion (I/R) injury is a major determinant of morbidity and mortality in patients undergoing treatment for cardiac disease. A variety of...
Myocardial ischemia/reperfusion (I/R) injury is a major determinant of morbidity and mortality in patients undergoing treatment for cardiac disease. A variety of treatments are reported to have benefits against reperfusion injury, yet their cardioprotective effects seem to be diminished in obesity, and the underlying mechanism remains elusive. In this study, we found that db/db mice exhibit cardiac hyper-O-GlcNAcylation. In parallel, palmitate treatment (200 mM; 12 h) in H9c2 cells showed an increase in global protein O-GlcNAcylation, along with an impaired insulin response against reperfusion injury. To investigate whether O-GlcNAcylation underlies this phenomenon, glucosamine was used to increase global protein O-GlcNAc levels. Interestingly, histological staining, electrophysiological studies, serum cardiac markers and oxidative stress biomarker assays showed that preischemic treatment with glucosamine attenuated insulin cardioprotection against myocardial infarction, arrhythmia and oxidative stress. Mechanistically, glucosamine treatment decreased insulin-stimulated Akt phosphorylation, a key modulator of cell survival. Furthermore, inhibition of O-GlcNAcylation via 6-diazo-5-oxo-l-norleucine (DON) apparently increased insulin-induced Akt phosphorylation and restored its cardioprotective response against reperfusion injury in palmitate-induced insulin-resistant H9c2 cells. Our findings demonstrated that obesity-induced hyper-O-GlcNAcylation might contribute to the attenuation of insulin cardioprotection against I/R injury.
Topics: Acetylglucosamine; Animals; Arrhythmias, Cardiac; Cardiotonic Agents; Cell Hypoxia; Cell Line; Diazooxonorleucine; Disease Models, Animal; Glycosylation; Humans; Insulin; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Myocardial Reperfusion Injury; Myocardium; Obesity; Protein Processing, Post-Translational; Rats
PubMed: 33915326
DOI: 10.1016/j.bbrc.2021.04.066 -
Journal of Neuropathology and... Mar 2021Medulloblastoma is the most common malignant pediatric brain tumor. Amplification of c-MYC is a hallmark of a subset of poor-prognosis medulloblastoma. MYC upregulates...
Medulloblastoma is the most common malignant pediatric brain tumor. Amplification of c-MYC is a hallmark of a subset of poor-prognosis medulloblastoma. MYC upregulates glutamine metabolism across many types of cancer. We modified the naturally occurring glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) by adding 2 promoeities to increase its lipophilicity and brain penetration creating the prodrug isopropyl 6-diazo-5-oxo-2-(((phenyl (pivaloyloxy) methoxy) - carbonyl) amino) hexanoate, termed JHU395. This prodrug was shown to have a 10-fold improved CSF-to-plasma ratio and brain-to-plasma ratio relative to DON. We hypothesized that JHU395 would have superior cell penetration compared with DON and would effectively and more potently kill MYC-expressing medulloblastoma. JHU395 treatment caused decreased growth and increased apoptosis in multiple human high-MYC medulloblastoma cell lines at lower concentrations than DON. Parenteral administration of JHU395 in Nu/Nu mice led to the accumulation of micromolar concentrations of DON in brain. Treatment of mice bearing orthotopic xenografts of human MYC-amplified medulloblastoma with JHU395 increased median survival from 26 to 45 days compared with vehicle control mice (p < 0.001 by log-rank test). These data provide preclinical justification for the ongoing development and testing of brain-targeted DON prodrugs for use in medulloblastoma.
Topics: Animals; Apoptosis; Caproates; Cell Line, Tumor; Cerebellar Neoplasms; Diazooxonorleucine; Dose-Response Relationship, Drug; Excitatory Amino Acid Antagonists; Female; Glutamine; Humans; Medulloblastoma; Mice; Mice, Nude
PubMed: 33712838
DOI: 10.1093/jnen/nlab018 -
Angewandte Chemie (International Ed. in... Apr 2021DON (6-diazo-5-oxo-l-norleucine), a diazo-containing amino acid, has been studied for more than 60 years as a potent antitumor agent, but its biosynthesis has not been...
DON (6-diazo-5-oxo-l-norleucine), a diazo-containing amino acid, has been studied for more than 60 years as a potent antitumor agent, but its biosynthesis has not been elucidated. Here we reveal the complete biosynthetic pathway of alazopeptin, the tripeptide Ala-DON-DON, which has antitumor activity, by gene inactivation and in vitro analysis of recombinant enzymes. We also established heterologous production of N-acetyl-DON in Streptomyces albus. DON is synthesized from lysine by three enzymes and converted to alazopeptin by five enzymes and one carrier protein. Most interestingly, transmembrane protein AzpL was indicated to catalyze diazotization using 5-oxolysine and nitrous acid as substrates. Site-directed mutagenesis of AzpL indicated that the hydroxy group of Tyr-93 is important for the diazotization. These findings expand our knowledge of the enzymology of N-N bond formation.
Topics: Alanine; Diazooxonorleucine; Dipeptides; Molecular Structure; Streptomyces
PubMed: 33624374
DOI: 10.1002/anie.202100462 -
Journal of Cellular Physiology Sep 2021Pre-eclampsia (PE) is a pregnancy-related disorder that occurs after 20 weeks of gestation. It seriously affects the health of maternity and the fetus. However, the...
Pre-eclampsia (PE) is a pregnancy-related disorder that occurs after 20 weeks of gestation. It seriously affects the health of maternity and the fetus. However, the pathogenesis of PE is still unknown. Decidualization deficiency is considered a contributing factor to the development of PE. CTP synthetase (CTPS) which is the rate-limiting enzyme in the CTP de novo biosynthesis, is essential for nucleic acid synthesis and cellular energy metabolism, and often appears as cytoophidium in many cell types. Here, we found that the expression of CTPS was significantly downregulated in decidual tissues of patients with severe PE compared with healthy pregnant women. During in vitro decidualization, changes in CTPS were accompanied by opposite fluctuation of the AMPK signaling pathway. Moreover, the downregulation of CTPS by glutamine analogs or CTPS small interfering RNA inhibited the decidualization process and the AMPK signaling pathway. Investigating the underlying mechanism of action by co-immunoprecipitation coupled with mass spectrometry showed that CTPS interacted with ATP synthase (ATPS) and maintained the content of ATP on Day 3 of decidualization. However, when combined with mitochondrial stress protein STRESS-70 instead of ATPS, the concentration of ATP on Day 6 of induction was reduced. Corresponding to this, CTPS was mainly distributes in the cytoplasm on Day 3 of induction, while it appeared both in the cytoplasm and the nucleus on Day 6 in decidualized cells, which was similar to that in cells before induction. In summary, we believe that CTPS plays an important role in decidualization by participating in energy metabolism. Abnormal expression of CTPS in decidualization would lead to abnormal decidualization and consequently result in the occurrence of PE.
Topics: Adenylate Kinase; Carbon-Nitrogen Ligases; Cell Line; Cell Proliferation; Decidua; Diazooxonorleucine; Down-Regulation; Endometrium; Energy Metabolism; Female; Gene Silencing; Human Embryonic Stem Cells; Humans; Mitochondrial Proton-Translocating ATPases; Pre-Eclampsia; Pregnancy; Protein Binding; Signal Transduction; Stromal Cells
PubMed: 33576499
DOI: 10.1002/jcp.30326 -
The Laryngoscope Jul 2021Glutamine inhibition has been demonstrated an antifibrotic effect in iatrogenic laryngotracheal stenosis (iLTS) scar fibroblasts in vitro. We hypothesize that broadly...
OBJECTIVE/HYPOTHESIS
Glutamine inhibition has been demonstrated an antifibrotic effect in iatrogenic laryngotracheal stenosis (iLTS) scar fibroblasts in vitro. We hypothesize that broadly active glutamine antagonist, DON will reduce collagen formation and fibrosis-associated gene expression in iLTS mice.
STUDY DESIGN
Prospective controlled animal study.
METHODS
iLTS in mice were induced by chemomechanical injury of the trachea using a bleomycin-coated wire brush. PBS or DON (1.3 mg/kg) were administered by intraperitoneal injection (i.p.) every other day. Laryngotracheal complexes were harvested at days 7 and 14 after the initiation of DON treatment for the measurement of lamina propria thickness, trichrome stain, immunofluorescence staining of collagen 1, and fibrosis-associated gene expression.
RESULTS
The study demonstrated that DON treatment reduced lamina propria thickness (P = .025) and collagen formation in trichrome stain and immunofluorescence staining of collagen 1. In addition, DON decreased fibrosis-associated gene expression in iLTS mice. At day 7, DON inhibited Col1a1 (P < .0001), Col3a1 (P = .0046), Col5a1 (P < .0001), and Tgfβ (P = .023) expression. At day 14, DON reduced Co1a1 (P = .0076) and Tgfβ (P = .023) expression.
CONCLUSIONS
Broadly active glutamine antagonist, DON, significantly reduces fibrosis in iLTS mice. These results suggest that the concept of glutamine inhibition may be a therapeutic option to reduce fibrosis in the laryngotracheal stenosis.
LEVEL OF EVIDENCE
N/A Laryngoscope, 131:E2125-E2130, 2021.
Topics: Animals; Bleomycin; Collagen; Diazooxonorleucine; Disease Models, Animal; Fibroblasts; Fibrosis; Gene Expression; Glutamine; Iatrogenic Disease; Injections, Intraperitoneal; Laryngostenosis; Mice; Mucous Membrane; Prospective Studies; Trachea; Tracheal Stenosis
PubMed: 33433011
DOI: 10.1002/lary.29385 -
Methods in Molecular Biology (Clifton,... 2021Colon cancer is a highly anabolic entity with upregulation of glycolysis, glutaminolysis, and de novo synthesis of fatty acids, which also induces a hypercatabolic state...
Colon cancer is a highly anabolic entity with upregulation of glycolysis, glutaminolysis, and de novo synthesis of fatty acids, which also induces a hypercatabolic state in the patient. The blockade of either cancer anabolism or host catabolism has been previously proven to be a successful anticancer experimental treatment. However, it is still unclear whether the simultaneous blockade of both metabolic counterparts can limit malignant survival and the energetic consequences of such an approach. In this chapter, by using the CT26.WT murine colon adenocarcinoma cell line as a model of study, we provide a method to simultaneously perform a pharmacological blockade of tumor anabolism and host catabolism, as a feasible therapeutic approach to treat cancer, and to limit its energetic supply.
Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Colonic Neoplasms; Diazooxonorleucine; Drug Screening Assays, Antitumor; Fatty Acid Synthase, Type I; Fatty Acids; Female; Glutaminase; Glutamine; Glycolysis; Hexokinase; Indazoles; Mice; Mice, Inbred BALB C; Molecular Targeted Therapy; Orlistat; Smegmamorpha
PubMed: 32813244
DOI: 10.1007/978-1-0716-0759-6_5 -
Frontiers in Immunology 2020Transplant tolerance in the absence of long-term immunosuppression has been an elusive goal for solid organ transplantation. Recently, it has become clear that metabolic...
Transplant tolerance in the absence of long-term immunosuppression has been an elusive goal for solid organ transplantation. Recently, it has become clear that metabolic reprogramming plays a critical role in promoting T cell activation, differentiation, and function. Targeting metabolism can preferentially inhibit T cell effector generation while simultaneously promoting the generation of T regulatory cells. We hypothesized that costimulatory blockade with CTLA4Ig in combination with targeting T cell metabolism might provide a novel platform to promote the induction of transplant tolerance.
Topics: Abatacept; Allografts; Animals; Deoxyglucose; Diazooxonorleucine; Glycolysis; Immunosuppression Therapy; Immunosuppressive Agents; Lymphocyte Activation; Metformin; Mice; T-Lymphocytes; Transplantation Tolerance
PubMed: 32328063
DOI: 10.3389/fimmu.2020.00572