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Cellular Immunology Dec 2021Infection of the cornea with HSV results in an immune-inflammatory reaction orchestrated by proinflammatory T cells that is a major cause of human vision impairment. The...
Infection of the cornea with HSV results in an immune-inflammatory reaction orchestrated by proinflammatory T cells that is a major cause of human vision impairment. The severity of lesions can be reduced if the representation of inflammatory T cells is changed to increase the presence of T cells with regulatory function. This report shows that inhibiting glutamine metabolism using 6-Diazo-5-oxo-l-norleucine (DON) administered via intraperitoneal (IP) starting 6 days after ocular infection and continued until day 15 significantly reduced the severity of herpetic stromal keratitis lesions. The therapy resulted in reduced neutrophils, macrophages as well proinflammatory CD4 Th1 and Th17 T cells in the cornea, but had no effect on levels of regulatory T cells. A similar change in the representation of inflammatory and regulatory T cells occurred in the trigeminal ganglion (TG) the site where HSV infection establishes latency. Glutamine metabolism was shown to be required for the in-vitro optimal induction of both Th1 and Th17 T cells but not for the induction of Treg that were increased when glutamine metabolism was inhibited. Inhibiting glutamine metabolism also changed the ability of latently infected TG cells from animals previously infected with HSV to reactivate and produce infectious virus.
Topics: Animals; Diazooxonorleucine; Glutamine; Keratitis, Herpetic; Latent Infection; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; T-Lymphocytes; Trigeminal Ganglion; Virus Activation; Virus Latency
PubMed: 34678554
DOI: 10.1016/j.cellimm.2021.104450 -
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 -
Physiological Reports Mar 2019Despite recent advances, acute respiratory distress syndrome (ARDS) remains a severe and often fatal disease for which there is no therapy able to reduce the underlying...
Despite recent advances, acute respiratory distress syndrome (ARDS) remains a severe and often fatal disease for which there is no therapy able to reduce the underlying excessive lung inflammation or enhance resolution of injury. Metabolic programming plays a critical role in regulating inflammatory responses. Due to their high metabolic needs, neutrophils, macrophages, and lymphocytes rely upon glutamine metabolism to support activation and function. Additionally, during times of physiologic stress, nearly all cells, including fibroblasts and epithelial cells, require glutamine metabolism. We hypothesized that inhibiting glutamine metabolism reduces lung inflammation and promotes resolution of acute lung injury. Lung injury was induced by instilling lipopolysaccharide (LPS) intratracheally. To inhibit glutamine metabolism, we administered a glutamine analogue, 6-diazo-5-oxo-L-norleucine (DON) that binds to glutamine-utilizing enzymes and transporters, after injury was well established. Treatment with DON led to less lung injury, fewer lung neutrophils, lung inflammatory and interstitial macrophages, and lower levels of proinflammatory cytokines and chemokines at 5 and/or 7 days after injury. Additionally, DON led to earlier expression of the growth factor amphiregulin and more rapid recovery of LPS-induced weight loss. Thus, DON reduced lung inflammation and promoted resolution of injury. These data contribute to our understanding of how glutamine metabolism regulates lung inflammation and repair, and identifies a novel target for future therapies for ARDS and other inflammatory lung diseases.
Topics: Acute Lung Injury; Amphiregulin; Animals; Anti-Inflammatory Agents; Antimetabolites; Cytokines; Diazooxonorleucine; Disease Models, Animal; Glutamine; Inflammation Mediators; Lipopolysaccharides; Lung; Macrophages; Mice, Inbred C57BL; Neutrophil Infiltration; Pneumonia; Time Factors
PubMed: 30821123
DOI: 10.14814/phy2.14019 -
Disaster Medicine and Public Health... Nov 2023Search and rescue teams and Antarctic research groups use protective cold-water anti-exposure suits (AES) when cruising on Zodiacs. Extremity tourniquet (ET)...
Search and rescue teams and Antarctic research groups use protective cold-water anti-exposure suits (AES) when cruising on Zodiacs. Extremity tourniquet (ET) self-application (SA) donned with AESs has not been previously studied. Our study therefore assessed the SA of 5 commercial ETs (CAT, OMNA, RATS, RMT, and SWAT-T) among 15 volunteers who donned these suits. Tourniquet's SA ability, ease of SA, tolerance, and tourniquet preference were measured. All ETs tested were self-applied to the upper extremity except for the SWAT, which was self-applied with the rest to the lower extremity. Ease- of- SA mean values were compared using the Friedman and Durbin-Conover post hoc tests < 0.001). Regarding the upper extremity, OMNA achieved the highest score of 8.5 out of 10, while RMT, and SWAT received lower scores than other options 0.001). For lower extremities, SWAT was found to be inferior to other options 0.01). Overall, OMNA was the best performer. The RATS showed significantly lower tolerance than the other groups in repeated- measures ANOVA with a Tukey post hoc test 0.01). Additionally, out of the 5 ETs tested, 60% of subjects preferred OMNA. The study concluded that SA commercial ETs are feasible over cold-water anti-exposure suits in the Antarctic climate.
Topics: Humans; Antarctic Regions; Tourniquets; Hemorrhage; Extremities; Diazooxonorleucine; Water
PubMed: 37937358
DOI: 10.1017/dmp.2023.179 -
Journal of Controlled Release :... Apr 2024Modulating the metabolism of cancer cells, immune cells, or both is a promising strategy to potentiate cancer immunotherapy in the nutrient-competitive tumor...
Modulating the metabolism of cancer cells, immune cells, or both is a promising strategy to potentiate cancer immunotherapy in the nutrient-competitive tumor microenvironment. Glutamine has emerged as an ideal target as cancer cells highly rely on glutamine for replenishing the tricarboxylic acid cycle in the process of aerobic glycolysis. However, non-specific glutamine restriction may induce adverse effects in unconcerned tissues and therefore glutamine inhibitors have achieved limited success in the clinic so far. Here we report the synthesis and evaluation of a redox-responsive prodrug of 6-Diazo-5-oxo-L-norleucine (redox-DON) for tumor-targeted glutamine inhibition. When applied to treat mice bearing subcutaneous CT26 mouse colon carcinoma, redox-DON exhibited equivalent antitumor efficacy but a greatly improved safety profile, particularly, in spleen and gastrointestinal tract, as compared to the state-of-the-art DON prodrug, JHU083. Furthermore, redox-DON synergized with checkpoint blockade antibodies leading to durable cures in tumor-bearing mice. Our results suggest that redox-DON is a safe and effective therapeutic for tumor-targeted glutamine inhibition showing promise for enhanced metabolic modulatory immunotherapy. The approach of reversible chemical modification may be generalized to other metabolic modulatory drugs that suffer from overt toxicity.
Topics: Animals; Mice; Diazooxonorleucine; Prodrugs; Glutamine; Colonic Neoplasms; Oxidation-Reduction; Tumor Microenvironment
PubMed: 38403173
DOI: 10.1016/j.jconrel.2024.02.031 -
JAMA Network Open Feb 2024Training on the proper use of personal protective equipment (PPE) is critical for infection prevention among health care workers. Traditional methods, such as... (Randomized Controlled Trial)
Randomized Controlled Trial
IMPORTANCE
Training on the proper use of personal protective equipment (PPE) is critical for infection prevention among health care workers. Traditional methods, such as face-to-face and video-based training, can strain resources and present challenges.
OBJECTIVE
To determine the effectiveness of 360° virtual reality (VR) training for PPE donning and doffing compared with face-to-face and video training in enhancing the PPE use skills of prospective health care practitioners.
DESIGN, SETTING, AND PARTICIPANTS
A blinded, prospective, and randomized noninferiority clinical trial was conducted from August to December 2021 at Teikyo University School of Medicine in Tokyo, Japan, with a mixed population of medical students. Participants were second- to fourth-year medicine, medical technology, or pharmacy students aged 20 years or older with no prior PPE training. Participants were randomized into 1 of 3 training groups (VR, face-to-face, or video) based on their enrollment order. An intention-to-treat analysis was conducted.
INTERVENTION
A 30-minute lecture on PPE procedures was delivered to all participants before the training. After the lecture, the VR group trained with an immersive 360° VR tool, the face-to-face group trained with actual PPE, and the video group trained by watching video footage on a computer and a projector. After 3 days, a standardized practical skills test was administered.
MAIN OUTCOMES AND MEASURES
The primary outcome was the mean score on a 20-point practical skills test, and the secondary outcome was the percentage of correct execution.
RESULTS
A total of 91 participants were recruited and randomized into 3 groups: VR (n = 30), face-to-face (n = 30), and video (n = 31) training. After excluding 1 participant due to illness, 90 participants (mean [SD] age, 24.2 [3.15] years; 54 males [60.0%]) completed the assessment. The mean (SD) scores were 17.70 (2.10) points for the VR group, 17.57 (2.45) points for the face-to-face group, and 15.87 (2.90) points for the video group. The VR group demonstrated no significant difference in performance from the face-to-face group. However, the VR group had significantly higher effectiveness than the video group (17.70 vs 15.87 points; P = .02).
CONCLUSIONS AND RELEVANCE
Results of this trial indicate that VR training was as effective as face-to-face training in enhancing PPE donning and doffing skills and was superior to video training. The findings suggest that VR training is a viable resource-conserving training option.
TRIAL REGISTRATION
Japan Registry of Clinical Trials Identifier: jRCT103021029.
Topics: Adult; Humans; Male; Young Adult; Diazooxonorleucine; Health Facilities; Health Personnel; Personal Protective Equipment; Schools; Female
PubMed: 38353953
DOI: 10.1001/jamanetworkopen.2023.55358 -
The Laryngoscope Feb 2018Management of laryngotracheal stenosis (LTS) remains primarily surgical, with a critical need to identify targets for adjuvant therapy. Laryngotracheal stenosis scar...
OBJECTIVE
Management of laryngotracheal stenosis (LTS) remains primarily surgical, with a critical need to identify targets for adjuvant therapy. Laryngotracheal stenosis scar fibroblasts exhibit a profibrotic phenotype with distinct metabolic shifts, including an increased glycolysis/oxidative phosphorylation ratio. This study examines the effects of the glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) on collagen production, gene expression, proliferation, and metabolism of human LTS-derived fibroblasts in vitro.
METHOD
Paired normal and scar-derived fibroblasts isolated from subglottic and proximal tracheal tissue in patients with iatrogenic laryngotracheal stenosis (iLTS) were cultured. Proliferation rate, gene expression, protein production, and cellular metabolism were assessed in two conditions: 1) fibroblast growth medium, and 2) fibroblast growth medium with 1 × 10 M DON.
RESULTS
DON treatment reduced cellular proliferation rate (n = 7, P = 0.0150). Expression of genes collagen 1 and collagen 3 both were reduced (n = 7, P = 0.0102, 0.0143, respectively). Soluble collagen production decreased (n = 7, P = 0.0056). As measured by the rate of extracellular acidification, glycolysis and glycolytic capacity decreased (n = 7, P = 0.0082, 0.0003, respectively). adenosine triphosphate (ATP) production and basal respiration decreased (n = 7, P = 0.0045, 0.0258, respectively), determined by measuring the cellular rate of oxygen consumption.
CONCLUSION
The glutamine antagonist DON reverses profibrotic changes by inhibiting both glycolysis and oxidative phosphorylation in iLTS scar fibroblasts. In contrast to untreated iLTS scar fibroblasts, collagen gene expression, protein production, metabolic rate, and proliferation were significantly reduced. These results suggest DON and/or its derivatives as strong candidates for adjuvant therapy in the management of iatrogenic laryngotracheal stenosis. Enzymes involved in glutamine metabolism inhibited by DON offer targets for future investigation.
LEVEL OF EVIDENCE
NA. Laryngoscope, 128:E59-E67, 2018.
Topics: Adult; Aged; Antimetabolites, Antineoplastic; Cell Culture Techniques; Cell Proliferation; Cicatrix; Collagen; Diazooxonorleucine; Female; Fibroblasts; Fibrosis; Gene Expression; Glycolysis; Humans; Iatrogenic Disease; Laryngostenosis; Male; Middle Aged; Oxygen Consumption; Real-Time Polymerase Chain Reaction; Tracheal Stenosis; Young Adult
PubMed: 28940431
DOI: 10.1002/lary.26893 -
The Journal of Clinical Investigation Jan 2020Pancreatic ductal adenocarcinoma (PDAC) is considered to be a highly immunosuppressive and heterogenous neoplasm. Despite improved knowledge regarding the genetic...
Pancreatic ductal adenocarcinoma (PDAC) is considered to be a highly immunosuppressive and heterogenous neoplasm. Despite improved knowledge regarding the genetic background of the tumor and better understanding of the tumor microenvironment, immune checkpoint inhibitor therapy (targeting CTLA4, PD1, PDL1) has not been very successful against PDAC. The robust desmoplastic stroma, along with an extensive extracellular matrix (ECM) that is rich in hyaluronan, plays an integral role in this immune evasion. Hexosamine biosynthesis pathway (HBP), a shunt pathway of glycolysis, is a metabolic node in cancer cells that can promote survival pathways on the one hand and influence the hyaluronan synthesis in the ECM on the other. The rate-limiting enzyme of the pathway, glutamine-fructose amidotransferase 1 (GFAT1), uses glutamine and fructose 6-phosphate to eventually synthesize uridine diphosphate N-acetylglucosamine (UDP-GlcNAc). In the current manuscript, we targeted this glutamine-utilizing enzyme by a small molecule glutamine analog (6-diazo-5-oxo-l-norleucine [DON]). Our results showed that DON decreased the self-renewal potential and metastatic ability of tumor cells. Further, treatment with DON decreased hyaluronan and collagen in the tumor microenvironment, leading to an extensive remodeling of the ECM and an increased infiltration of CD8+ T cells. Additionally, treatment with DON sensitized pancreatic tumors to anti-PD1 therapy, resulting in tumor regression and prolonged survival.
Topics: Animals; CD8-Positive T-Lymphocytes; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Diazooxonorleucine; Female; Hexosamines; Humans; Mice; Mice, Nude; Neoplasm Metastasis; Neoplasm Proteins; Pancreatic Neoplasms; Programmed Cell Death 1 Receptor; Xenograft Model Antitumor Assays
PubMed: 31613799
DOI: 10.1172/JCI127515 -
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