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Cell Reports Oct 2015Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic...
Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG), the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON). Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.
Topics: Allografts; Animals; CD8-Positive T-Lymphocytes; Cells, Cultured; Deoxyglucose; Diazooxonorleucine; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Glutamine; Glycolysis; Graft Rejection; Heart Transplantation; Metformin; Mice; Mice, Inbred BALB C; Mice, Transgenic; Phosphorylation; T-Lymphocytes, Regulatory
PubMed: 26489460
DOI: 10.1016/j.celrep.2015.09.036 -
Pharmacologically Inferred Glycolysis and Glutaminolysis Requirement of B Cells in Lupus-Prone Mice.Journal of Immunology (Baltimore, Md. :... May 2022Several studies have shown an enhanced metabolism in the CD4 T cells of lupus patients and lupus-prone mice. Little is known about the metabolism of B cells in lupus. In...
Several studies have shown an enhanced metabolism in the CD4 T cells of lupus patients and lupus-prone mice. Little is known about the metabolism of B cells in lupus. In this study, we compared the metabolism of B cells between lupus-prone B6. triple-congenic mice and C57BL/6 controls at steady state relative to autoantibody production, as well as during T cell-dependent (TD) and T cell-independent (TI) immunizations. Starting before the onset of autoimmunity, B cells from triple-congenic mice showed an elevated glycolysis and mitochondrial respiration, which were normalized in vivo by inhibiting glycolysis with a 2-deoxy-d-glucose (2DG) treatment. 2DG greatly reduced the production of TI-Ag-specific Abs, but showed minimal effect with TD-Ags. In contrast, the inhibition of glutaminolysis with 6-diazo-5-oxo-l-norleucine had a greater effect on TD than TI-Ag-specific Abs in both strains. Analysis of the TI and TD responses in purified B cells in vitro suggests, however, that the glutaminolysis requirement is not B cell-intrinsic. Thus, B cells have a greater requirement for glycolysis in TI than TD responses, as inferred from pharmacological interventions. B cells from lupus-prone and control mice have different intrinsic metabolic requirements or different responses toward 2DG and 6-diazo-5-oxo-l-norleucine, which mirrors our previous results obtained with follicular Th cells. Overall, these results predict that targeting glucose metabolism may provide an effective therapeutic approach for systemic autoimmunity by eliminating both autoreactive follicular Th and B cells, although it may also impair TI responses.
Topics: Animals; B-Lymphocytes; Diazooxonorleucine; Glycolysis; Humans; Mice; Mice, Congenic; Mice, Inbred C57BL; T-Lymphocytes, Helper-Inducer
PubMed: 35387839
DOI: 10.4049/jimmunol.2100356 -
Nature Reviews. Drug Discovery Dec 2015
Topics: Animals; Antimalarials; Diazooxonorleucine; Glutamine; Malaria, Cerebral; Malaria, Falciparum
PubMed: 26585535
DOI: 10.1038/nrd4786 -
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 -
Brazilian Oral Research 2023The current study aims to assess the effectiveness of e-learning in compliance with the new biosafety recommendations in dentistry in the context of COVID-19 applied to...
The current study aims to assess the effectiveness of e-learning in compliance with the new biosafety recommendations in dentistry in the context of COVID-19 applied to the clinical staff of a dental school in Brazil. A quasi-experimental epidemiological study was carried out by means of a structured, pre-tested online questionnaire, applied before and after an educational intervention, using an e-learning format. After data collection, statistical tests were performed. A total of 549 members of the clinical staff participated in the study in the two collection phases, with a return rate of 26.9%. After the e-learning stage, a reduction was found in the reported use of disposable gloves, protective goggles, and surgical masks. The course had no impact on the staff's knowledge concerning the proper sequence for donning PPE and showed 100% effectiveness regarding proper PPE doffing sequence. Knowledge about avoiding procedures that generate aerosols in the clinical setting was improved. Despite the low rate of return, it can be concluded that online intervention alone was ineffective in significantly improving learning about the new clinical biosafety guidelines. Therefore, the use of hybrid teaching and repetitive training is highly recommended.
Topics: Humans; Computer-Assisted Instruction; COVID-19; Brazil; Diazooxonorleucine; Dentistry
PubMed: 37341233
DOI: 10.1590/1807-3107bor-2023.vol37.0060 -
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 -
Recent Results in Cancer Research.... 1980DON (6-diazo-5-oxo-L-norleucine) and azotomycin are glutamine antagonists that were tested in human malignancies in the 1950s. Azotomycin demonstrated significant...
DON (6-diazo-5-oxo-L-norleucine) and azotomycin are glutamine antagonists that were tested in human malignancies in the 1950s. Azotomycin demonstrated significant activity in colorectal cancer. DON is probably the active form of azotomycin. Recent impressive results for both of these agents in human tumor xenografts (especially the CX-2 colon tumor) have stimulated renewed clinical interest in DON, the more readily available agent. DON mechanism of action, clinical pharmacology, previous clinical data, and current phase I studies are discussed.
Topics: Animals; Azo Compounds; Diazooxonorleucine; Humans; Neoplasm Proteins; Neoplasms, Experimental; Purines; Pyrimidines
PubMed: 7192426
DOI: 10.1007/978-3-642-81488-4_30 -
Journal of Safety Research Sep 2023Worn shoes are an important contributor to occupational slip and fall injuries. Tools to assess worn tread are emerging; imaging tools offer the potential to assist. The...
PROBLEM
Worn shoes are an important contributor to occupational slip and fall injuries. Tools to assess worn tread are emerging; imaging tools offer the potential to assist. The aim of this study was to develop a shoe tread scanner and evaluate its effectiveness to predict slip risk.
METHODS
This study analyzed data from two previous studies in which worn or new slip-resistant shoes were donned during an unexpected slip condition. The shoe tread for each shoe was scanned using a portable scanner that utilized frustrated total internal reflection (FTIR) technology. The shoe tread parameters of the worn region size (WRS) for worn shoes and total contact area for new shoes were measured. These parameters were then used to predict slip risk from the unexpected slip conditions.
RESULTS
The WRS was able to accurately predict slip risk, but the contact area was not.
DISCUSSION
These findings support that increased WRS on the shoe outsole is associated with worse slip outcomes. Furthermore, the tool was able to offer robust feedback across a wide range of tread designs, but the results of this study show that the tool may be more applicable for slip-resistant shoes that are worn compared to their new counterparts.
SUMMARY
This study shows that FTIR technology utilized in this tool may be a useful and portable method for determining slip risk for worn shoes.
PRACTICAL APPLICATIONS
This tool has the potential to be an efficient, objective, end-user tool that improves timely replacement of shoes and prevention of injuries.
Topics: Humans; Shoes; Diazooxonorleucine; Technology
PubMed: 37718069
DOI: 10.1016/j.jsr.2023.05.014 -
Cancer Treatment Reports Jun 1979
Topics: Animals; Antineoplastic Agents; Azaserine; Azo Compounds; Diazooxonorleucine; Drug Administration Schedule; Drug Therapy, Combination; Humans; Leukemia, Experimental; Mice; Neoplasms
PubMed: 466642
DOI: No ID Found -
Journal of Medicinal Chemistry Nov 2023The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) exhibits remarkable anticancer efficacy; however, its therapeutic potential is hindered by its toxicity to...
The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) exhibits remarkable anticancer efficacy; however, its therapeutic potential is hindered by its toxicity to gastrointestinal (GI) tissues. We recently reported the discovery of DRP-104, a tumor-targeted DON prodrug with excellent efficacy and tolerability, which is currently in clinical trials. However, DRP-104 exhibits limited aqueous solubility, and the instability of its isopropyl ester promoiety leads to the formation of an inactive M1-metabolite, reducing overall systemic prodrug exposure. Herein, we aimed to synthesize DON prodrugs with various ester and amide promoieties with improved solubility, GI stability, and DON tumor delivery. Twenty-one prodrugs were synthesized and characterized in stability and pharmacokinetics studies. Of these, , -butyl-()-6-diazo-2-(()-2-(2-(dimethylamino)acetamido)-3-phenylpropanamido)-5-oxo-hexanoate, showed excellent metabolic stability in plasma and intestinal homogenate, high aqueous solubility, and high tumor DON exposures and preserved the ideal tumor-targeting profile of DRP-104. In conclusion, we report a new generation of glutamine antagonist prodrugs with improved physicochemical and pharmacokinetic attributes.
Topics: Humans; Prodrugs; Diazooxonorleucine; Glutamine; Esters; Neoplasms
PubMed: 37949450
DOI: 10.1021/acs.jmedchem.3c01681