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BACKGROUND: The association between low-frequency human immunodeficiency virus type 1 (HIV-1) drug resistance mutations (DRMs) and treatment failure (TF) is controversial. We explore this association using next-generation sequencing (NGS) methods that accurately sample low-frequency DRMs. METHODS: We enrolled women with HIV-1 in Malawi who were either antiretroviral therapy (ART) naive (cohort A), had ART failure (cohort B), or had discontinued ART (cohort C). At entry, cohorts A and C began a nonnucleoside reverse transcriptase inhibitor-based regimen and cohort B started a protease inhibitor-based regimen. We used Primer ID MiSeq to identify regimen-relevant DRMs in entry and TF plasma samples, and a Cox proportional hazards model to calculate hazard ratios (HRs) for entry DRMs. Low-frequency DRMs were defined as ≤20%. RESULTS: We sequenced 360 participants. Cohort B and C participants were more likely to have TF than cohort A participants. The presence of K103N at entry significantly increased TF risk among A and C participants at both high and low frequency, with HRs of 3.12 (95% confidence interval [CI], 1.58-6.18) and 2.38 (95% CI, 1.00-5.67), respectively. At TF, 45% of participants showed selection of DRMs while in the remaining participants there was an apparent lack of selective pressure from ART. CONCLUSIONS: Using accurate NGS for DRM detection may benefit an additional 10% of patients by identifying low-frequency K103N mutations.
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Farmacorresistência Viral , Infecções por HIV , HIV-1 , Mutação , Falha de Tratamento , Humanos , HIV-1/genética , HIV-1/efeitos dos fármacos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Farmacorresistência Viral/genética , Adulto , Malaui , Fármacos Anti-HIV/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Estudos de Coortes , Adulto Jovem , Resultado do TratamentoRESUMO
BACKGROUND: The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic posed an unpreceded threat to the management of other pandemics such as human immunodeficiency virus-1 (HIV-1) in the United States. The full impact of the SARS-CoV-2 pandemic on the HIV-1 pandemic needs to be evaluated. METHODS: All individuals with newly reported HIV-1 diagnoses from NC State Laboratory of Public Health were enrolled in this prospective observational study, 2018-2021. We used a sequencing-based recency assay to identify recent HIV-1 infections and to determine the days postinfection (DPI) for each person at the time of diagnosis. RESULTS: Sequencing used diagnostic serum samples from 814 individuals with new HIV-1 diagnoses spanning this 4-year period. Characteristics of individuals diagnosed in 2020 differed from those in other years. People of color diagnosed in 2021 were on average 6 months delayed in their diagnosis compared to those diagnosed in 2020. There was a trend that genetic networks were more known for individuals diagnosed in 2021. We observed no major integrase resistance mutations over the course of the study. CONCLUSIONS: SARS-CoV-2 pandemic may contribute to the spread of HIV-1. Public health resources need to focus on restoring HIV-1 testing and interrupting active, ongoing, transmission.
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COVID-19 , HIV-1 , Humanos , Estados Unidos/epidemiologia , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , HIV-1/genética , Pandemias , Sequenciamento de Nucleotídeos em Larga Escala , Teste para COVID-19RESUMO
Mutagenic ribonucleosides can act as broad-based antiviral agents. They are metabolized to the active ribonucleoside triphosphate form and concentrate in genomes of RNA viruses during viral replication. ß-d-N4-hydroxycytidine (NHC, initial metabolite of molnupiravir) is >100-fold more active than ribavirin or favipiravir against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with antiviral activity correlated to the level of mutagenesis in virion RNA. However, NHC also displays host mutational activity in an animal cell culture assay, consistent with RNA and DNA precursors sharing a common intermediate of a ribonucleoside diphosphate. These results indicate highly active mutagenic ribonucleosides may hold risk for the host.
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Antivirais/farmacologia , Citidina/análogos & derivados , Mutagênicos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/efeitos adversos , Células CHO/efeitos dos fármacos , Células Cultivadas , Cricetulus , Citidina/efeitos adversos , Citidina/farmacologia , Relação Dose-Resposta a Droga , Mutagênese/efeitos dos fármacos , Mutagênicos/efeitos adversos , SARS-CoV-2/genética , Replicação Viral/efeitos dos fármacosRESUMO
Pyruvate kinase (PK) deficiency is a rare genetic disease that causes chronic hemolytic anemia. There are currently no targeted therapies for PK deficiency. Here, we describe the identification and characterization of AG-348, an allosteric activator of PK that is currently in clinical trials for the treatment of PK deficiency. We demonstrate that AG-348 can increase the activity of wild-type and mutant PK enzymes in biochemical assays and in patient red blood cells treated ex vivo. These data illustrate the potential for AG-348 to restore the glycolytic pathway activity in patients with PK deficiency and ultimately lead to clinical benefit.
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Ativadores de Enzimas/farmacologia , Ativadores de Enzimas/uso terapêutico , Eritrócitos/enzimologia , Piruvato Quinase/deficiência , Piruvato Quinase/metabolismo , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Anemia Hemolítica Congênita não Esferocítica , Animais , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/química , Eritrócitos/efeitos dos fármacos , Humanos , Cinética , Camundongos , Piperazinas , Piruvato Quinase/efeitos dos fármacos , Erros Inatos do Metabolismo dos Piruvatos , Quinolinas/química , Proteínas Recombinantes/metabolismo , Sulfonamidas/química , Doadores de TecidosRESUMO
Pyruvate kinase deficiency (PKD) is a monogenic metabolic disease caused by mutations in the PKLR gene that leads to hemolytic anemia of variable symptomatology and that can be fatal during the neonatal period. PKD recessive inheritance trait and its curative treatment by allogeneic bone marrow transplantation provide an ideal scenario for developing gene therapy approaches. Here, we provide a preclinical gene therapy for PKD based on a lentiviral vector harboring the hPGK eukaryotic promoter that drives the expression of the PKLR cDNA. This therapeutic vector was used to transduce mouse PKD hematopoietic stem cells (HSCs) that were subsequently transplanted into myeloablated PKD mice. Ectopic RPK expression normalized the erythroid compartment correcting the hematological phenotype and reverting organ pathology. Metabolomic studies demonstrated functional correction of the glycolytic pathway in RBCs derived from genetically corrected PKD HSCs, with no metabolic disturbances in leukocytes. The analysis of the lentiviral insertion sites in the genome of transplanted hematopoietic cells demonstrated no evidence of genotoxicity in any of the transplanted animals. Overall, our results underscore the therapeutic potential of the hPGK-coRPK lentiviral vector and provide high expectations toward the gene therapy of PKD and other erythroid metabolic genetic disorders.
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Anemia Hemolítica Congênita não Esferocítica/genética , Anemia Hemolítica Congênita não Esferocítica/terapia , Terapia Genética , Piruvato Quinase/deficiência , Erros Inatos do Metabolismo dos Piruvatos/genética , Erros Inatos do Metabolismo dos Piruvatos/terapia , Anemia Hemolítica Congênita não Esferocítica/metabolismo , Animais , Células Sanguíneas/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Eritrócitos/citologia , Eritrócitos/metabolismo , Eritropoese , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/genética , Glicólise , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Lentivirus/genética , Redes e Vias Metabólicas , Metaboloma , Metabolômica , Camundongos , Camundongos Transgênicos , Mutação , Fenótipo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Erros Inatos do Metabolismo dos Piruvatos/metabolismo , Transdução GenéticaRESUMO
BACKGROUND: Renal colic caused by stone(s) is common in the emergency department. Often, urinalysis reveals white blood cells, but it is unknown how frequently pyuria is sterile or infectious. OBJECTIVES: We sought to determine the incidence of pyuria in patients with renal colic and to correlate the incidence with a positive urine culture. METHODS: A 1-year retrospective review of adult patients with renal colic presenting to three community emergency departments was performed. Patients without confirmed renal stone(s) or completed urinalysis were excluded. Hematuria is defined as ≥5 red blood cells per high power field (RBC/HPF) and pyuria as >10 white blood cells per high power field (WBC/HPF). A positive urine culture is defined as >100,000 colony forming units per milliliter. Student's t-test, chi square, or Fisher's exact tests were performed as appropriate, with significance set at 0.05. RESULTS: There were 339 patients who satisfied the inclusion and exclusion criteria, and 14.2% of these patients had associated pyuria. There were 153 (45.1%) urine cultures performed, and 16 (10.5%) were positive. Patients with pyuria were more likely to have a positive urine culture (36.4% vs. 3.3%, respectively; p < 0.001). The percentage of positive urine cultures increased (p < 0.001) with increasing pyuria from 9.1% (10-20 WBC/HPF) to 60.0% (>50 WBC/HPF). Positive cultures also increased (p < 0.001) with increased leukocyte esterase observed on macroscopic samples, from 1.6% (small or less leukocyte esterase) to 77.8% (large-volume leukocyte esterase). CONCLUSION: Pyuria was found in 14.2% of patients with renal colic. Patients with pyuria had 36.4% positive cultures compared to 3.3% of patients without pyuria. The degree of pyuria or leukocyte esterase was significantly associated with the risk of a positive culture. Urine cultures are recommended for all patients with renal colic and pyuria.
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Bacteriúria/epidemiologia , Cálculos Renais/complicações , Piúria/epidemiologia , Cólica Renal/etiologia , Cólica Renal/urina , Doença Aguda , Adulto , Idoso , Hidrolases de Éster Carboxílico/urina , Feminino , Hematúria/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores SexuaisRESUMO
Tissue engineered scaffolds aimed at the repair of critical-sized bone defects lack adequate consideration for our aging society. Establishing an effective aged in vitro model that translates to animals is a significant unmet challenge. The in vivo aged environment is complex and highly nuanced, making it difficult to model in the context of bone repair. In this work, 3D nanofibrous scaffolds generated by the thermally-induced self-agglomeration (TISA) technique were functionalized with polydopamine nanoparticles (PD NPs) as a tool to improve drug binding capacity and scavenge reactive oxygen species (ROS), an excessive build-up that dampens the healing process in aged tissues. PD NPs were reduced by ascorbic acid (rPD) to further improve hydrogen peroxide (H2O2) scavenging capabilities, where we hypothesized that these functionalized scaffolds could rescue ROS-affected osteoblastic differentiation in vitro and improve new bone formation in an aged mouse model. rPDs demonstrated improved H2O2 scavenging activity compared to neat PD NPs, although both NP groups rescued the alkaline phosphatase activity (ALP) of MC3T3-E1 cells in presence of H2O2. Additionally, BMP2-induced osteogenic differentiation, both ALP and mineralization, was significantly improved in the presence of PD or rPD NPs on TISA scaffolds. While in vitro data showed favorable results aimed at improving osteogenic differentiation by PD or rPD NPs, in vivo studies did not note similar improvements in ectopic bone formation an aged model, suggesting that further nuance in material design is required to effectively translate to improved in vivo results in aged animal models.
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Regeneração Óssea , Indóis , Nanopartículas , Osteogênese , Polímeros , Espécies Reativas de Oxigênio , Alicerces Teciduais , Animais , Camundongos , Indóis/química , Indóis/farmacologia , Osteogênese/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia , Alicerces Teciduais/química , Regeneração Óssea/efeitos dos fármacos , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Nanofibras/química , Peróxido de Hidrogênio/química , Envelhecimento/metabolismo , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Osteoblastos/metabolismoRESUMO
Anoxia halts oxidative phosphorylation (OXPHOS) causing an accumulation of reduced compounds in the mitochondrial matrix which impedes dehydrogenases. By simultaneously measuring oxygen concentration, NADH autofluorescence, mitochondrial membrane potential and ubiquinone reduction extent in isolated mitochondria in real-time, we demonstrate that Complex I utilized endogenous quinones to oxidize NADH under acute anoxia. 13C metabolic tracing or untargeted analysis of metabolites extracted during anoxia in the presence or absence of site-specific inhibitors of the electron transfer system showed that NAD+ regenerated by Complex I is reduced by the 2-oxoglutarate dehydrogenase Complex yielding succinyl-CoA supporting mitochondrial substrate-level phosphorylation (mtSLP), releasing succinate. Complex II operated amphidirectionally during the anoxic event, providing quinones to Complex I and reducing fumarate to succinate. Our results highlight the importance of quinone provision to Complex I oxidizing NADH maintaining glutamate catabolism and mtSLP in the absence of OXPHOS.
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Mitocôndrias , NAD , Humanos , NAD/metabolismo , Mitocôndrias/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Quinonas/metabolismo , Fosforilação Oxidativa , Succinatos/metabolismo , Hipóxia/metabolismo , OxirreduçãoRESUMO
A diverse group of RNA viruses including Rabies, Polio, La Crosse, West Nile, Zika, Nipah, Eastern and Western equine encephalitis, Venezuelan equine encephalitis, Japanese encephalitis, and tick-borne encephalitis viruses have the ability to gain access to and replicate in the central nervous system (CNS), causing severe neurological disease. Current treatment for these patients is generally limited to supportive care. To address the need for a generalizable antiviral, we utilized a strategy of mutagenesis to limit virus replication. We evaluated ribavirin (RBV), favipiravir (FAV) and N 4 -hydroxycytidine (NHC) against La Crosse virus (LACV) which is the primary cause of pediatric arboviral encephalitis cases in North America. NHC was more potent than RBV or FAV in neuronal cells. Oral administration of molnupiravir (MOV), the 5'-isobutyryl prodrug of NHC, decreased neurological disease development by 32% following intraperitoneal (IP) infection of LACV. MOV also reduced disease by 23% when virus was administered intranasally (IN). NHC and MOV produced less fit viruses by incorporating predominantly G-to-A or C-to-U mutations. Furthermore, NHC also inhibited two other orthobunyaviruses, Jamestown Canyon virus and Cache Valley virus. Collectively, these studies indicate that NHC/MOV has therapeutic potential to inhibit virus replication and subsequent neurological disease caused by this neurotropic RNA virus.
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High-Performance Liquid Chromatography-Tandem Mass Spectrometry has emerged triumphant over the years as a reliable and high throughput clinical instrument to assess different metabolic irregularities. One of the latest applications of LC-MS/MS has been in the field of quantification of glucocorticoids, such as cortisol and cortisone from saliva, that can be an indicator of abnormalities such as Congenital Adrenal Hyperplasia (CAH), Cushing's Syndrome, and Addison's disease. We have developed and validated an LC-MS/MS-based assay for simultaneous detection of cortisol and cortisone in human saliva, which requires only 20 µL of sample, to measure cortisol across a 0.5 - 70 ng/mL range, and cortisone across a 1.2- 100 ng/mL range, respectively. The developed method exhibits linearity of R2>0.99, for both analytes, inclusive of both MRMs, and a percent coefficient of variation that is less than or equal to 20%. Using dilute-and-shoot for sample preparation, we have exhibited sample accuracy of 100±20 for the assay calibrators, and integrated Needle Wash Solvent Chemistry for minimal sample carryover, making it adaptable for crucial for potential diagnostic use. We have exhibited a method that is simplistic, specific, and highly automatable on liquid handling platforms, such as the JANUS® G3 Workstation. With our innovation, we have introduced a potential to test 81-unknown samples in singlicate within an on-deck plating time of fewer than four minutes. We performed additional verification studies, including an accelerated stability study and a freeze-thaw study showcasing the potential long-term usability of our proposed prototype kit. Overall, this work presents an optimized LC-MS/MS method with automated sample preparation that is ready to be utilized for cortisol-cortisone detection for clinical diagnostic contexts related to Cushing's Disease, among other adrenal and endocrine disorders.
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Cortisona , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cortisona/análise , Humanos , Hidrocortisona/análise , Espectrometria de Massas em Tandem/métodosRESUMO
Next generation sequencing (NGS)/deep sequencing has become an important tool in the study of viruses. The use of unique molecular identifiers (UMI) can overcome the limitations of PCR errors and PCR-mediated recombination and reveal the true sampling depth of a viral population being sequenced in an NGS experiment. This approach of enhanced sequence data represents an ideal tool to study both high and low abundance drug resistance mutations and more generally to explore the genetic structure of viral populations. Central to the use of the UMI/Primer ID approach is the creation of a template consensus sequence (TCS) for each genome sequenced. Here we describe a series of experiments to validate several aspects of the Multiplexed Primer ID (MPID) sequencing approach using the MiSeq platform. We have evaluated how multiplexing of cDNA synthesis and amplicons affects the sampling depth of the viral population for each individual cDNA and amplicon to understand the relationship between broader genome coverage versus maximal sequencing depth. We have validated reproducibility of the MPID assay in the detection of minority mutations in viral genomes. We have also examined the determinants that allow sequencing reads of PCR recombinants to contaminate the final TCS data set and show how such contamination can be limited. Finally, we provide several examples where we have applied MPID to analyze features of minority variants and describe limits on their detection in viral populations of HIV-1 and SARS-CoV-2 to demonstrate the generalizable utility of this approach with any RNA virus.
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COVID-19 , Humanos , Reprodutibilidade dos Testes , SARS-CoV-2/genética , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
Next generations sequencing (NGS) has become an important tool in biomedical research. The Primer ID approach combined with the MiSeq platform overcomes the limitation of PCR errors and reveals the true sampling depth of population sequencing, making it an ideal tool to study mutagenic effects of potential broad-spectrum antivirals on RNA viruses. In this report we describe a protocol using Primer ID sequencing to study the mutations induced by antivirals in a coronavirus genome from an in vitro cell culture model and an in vivo mouse model. Viral RNA or total lung tissue RNA is tagged with Primer ID-containing cDNA primers during the initial reverse transcription step, followed by two rounds of PCR to amplify viral sequences and incorporate sequencing adaptors. Purified and pooled libraries are sequenced using the MiSeq platform. Sequencing data are processed using the template consensus sequence (TCS) web-app. The Primer ID approach provides an accurate sequencing protocol to measure mutation error rates in viral RNA genomes and host mRNA. Sequencing results suggested that ß-D-N4-hydroxycytidine (NHC) greatly increased the transition substitution rate but not the transversion substitution rate in the viral RNA genomes, and cytosine (C) to uridine (U) was found as the most frequently seen mutation.
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Correction for 'Mechanical rigidity of a shape-memory metal-organic framework increases by crystal downsizing' by Al A. Tiba et al., Chem. Commun., 2021, 57, 89-92, DOI: 10.1039/D0CC05684G.
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Soft porous nanocrystals with a pronounced shape-memory effect exhibit two- to three-fold increase in elastic modulus compared to the microcrystalline counterpart as determined by atomic force microscopy nanoindentation. The increase in rigidity is consistent with the known shape-memory effect displayed by the framework solid at the nanoscale. Crystal downsizing can offer new avenues for tailoring the mechanical properties of metal-organic frameworks.
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A 47-year-old male with no significant medical history was hospitalized for bacteremia and diagnosed with endocarditis. The organism isolated was a Gram-negative bacillus-Sphingomonas paucimobilis. There are only a few reported cases of endocarditis caused by S. paucimobilis, and to our knowledge, this is the first in the United States.
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Coronaviruses (CoVs) traffic frequently between species resulting in novel disease outbreaks, most recently exemplified by the newly emerged SARS-CoV-2, the causative agent of COVID-19. Here, we show that the ribonucleoside analog ß-d-N4-hydroxycytidine (NHC; EIDD-1931) has broad-spectrum antiviral activity against SARS-CoV-2, MERS-CoV, SARS-CoV, and related zoonotic group 2b or 2c bat-CoVs, as well as increased potency against a CoV bearing resistance mutations to the nucleoside analog inhibitor remdesivir. In mice infected with SARS-CoV or MERS-CoV, both prophylactic and therapeutic administration of EIDD-2801, an orally bioavailable NHC prodrug (ß-d-N4-hydroxycytidine-5'-isopropyl ester), improved pulmonary function and reduced virus titer and body weight loss. Decreased MERS-CoV yields in vitro and in vivo were associated with increased transition mutation frequency in viral, but not host cell RNA, supporting a mechanism of lethal mutagenesis in CoV. The potency of NHC/EIDD-2801 against multiple CoVs and oral bioavailability highlights its potential utility as an effective antiviral against SARS-CoV-2 and other future zoonotic CoVs.
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Antivirais/administração & dosagem , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Ribonucleosídeos/administração & dosagem , Replicação Viral/efeitos dos fármacos , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Alanina/administração & dosagem , Alanina/análogos & derivados , Animais , Antibioticoprofilaxia , Betacoronavirus/fisiologia , COVID-19 , Linhagem Celular , Infecções por Coronavirus/patologia , Citidina/administração & dosagem , Citidina/análogos & derivados , Modelos Animais de Doenças , Farmacorresistência Viral , Humanos , Hidroxilaminas , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Modelos Moleculares , Mutação/efeitos dos fármacos , Pandemias , Pneumonia Viral/patologia , Cultura Primária de Células , RNA Viral , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/genética , Distribuição Aleatória , Sistema Respiratório/citologia , SARS-CoV-2RESUMO
Glioblastoma (GBM) is an aggressive primary human brain tumour that has resisted effective therapy for decades. Although glucose and glutamine are the major fuels that drive GBM growth and invasion, few studies have targeted these fuels for therapeutic management. The glutamine antagonist, 6-diazo-5-oxo-L-norleucine (DON), was administered together with a calorically restricted ketogenic diet (KD-R) to treat late-stage orthotopic growth in two syngeneic GBM mouse models: VM-M3 and CT-2A. DON targets glutaminolysis, while the KD-R reduces glucose and, simultaneously, elevates neuroprotective and non-fermentable ketone bodies. The diet/drug therapeutic strategy killed tumour cells while reversing disease symptoms, and improving overall mouse survival. The therapeutic strategy also reduces edema, hemorrhage, and inflammation. Moreover, the KD-R diet facilitated DON delivery to the brain and allowed a lower dosage to achieve therapeutic effect. The findings support the importance of glucose and glutamine in driving GBM growth and provide a therapeutic strategy for non-toxic metabolic management.
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Neoplasias Encefálicas/terapia , Restrição Calórica , Dieta Cetogênica , Glioblastoma/terapia , Glutamina/metabolismo , Animais , Peso Corporal , Encéfalo/metabolismo , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Diazo-Oxo-Norleucina/uso terapêutico , Modelos Animais de Doenças , Feminino , Fermentação , Glioblastoma/metabolismo , Glucose/metabolismo , Humanos , Imuno-Histoquímica , Corpos Cetônicos/metabolismo , Cetonas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de NeoplasiasRESUMO
BACKGROUND: Cancer cells have altered bioenergetics, which contributes to their ability to proliferate, survive in unusual microenvironments, and invade other tissues. Changes in glucose metabolism can have pleomorphic effects on tumor cells. METHODS: To investigate potential mechanisms responsible for the increased malignancy associated with altered glucose metabolism, we used an unbiased nuclear magnetic resonance spectroscopy screening method to identify glucose metabolites differentially produced in a highly malignant human triple-negative breast cancer (TNBC) cell line (BPLER) and a less malignant isogenic TNBC cell line (HMLER). RESULTS: N-acetylneuraminic acid (Neu5Ac), the predominant sialic acid derivative in mammalian cells, which forms the terminal sugar on mucinous cell surface glycoproteins, was the major glucose metabolite that differed. Neu5Ac was ~7-fold more abundant in BPLER than HMLER. Loss of Neu5Ac by enzymatic removal or siRNA knockdown of cytidine monophosphate N-acetylneuraminic acid synthetase (CMAS), which activates cellular sialic acids for glycoprotein conjugation, had no significant effect on cell proliferation, but decreased the ability of BPLER to invade through a basement membrane. Conversely, overexpressing CMAS in HMLER increased invasivity. TNBCs in The Cancer Genome Atlas also had significantly more CMAS copy number variations and higher mRNA expression than non-TNBC, which have a better prognosis. CMAS knockdown in BPLER ex vivo blocked xenograft formation in mice. CONCLUSION: Neu5Ac is selectively highly enriched in aggressive TNBC, and CMAS, the enzyme required for sialylation, may play an important role in TNBC tumor formation and invasivity.
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Recently, we have shown that ketamine given prior to stress exposure protects against the development of depressive-like behavior in mice. These data suggest that it may be possible to prevent the induction of affective disorders before they develop by administering prophylactic pharmaceuticals, a relatively nascent and unexplored strategy for psychiatry. Here, we performed metabolomics analysis of brain and plasma following prophylactic ketamine treatment in order to identify markers of stress resilience enhancement. We administered prophylactic ketamine in mice to buffer against fear expression. Following behavioral analyses, untargeted metabolomic profiling was performed on both hemispheres of the prefrontal cortex (PFC) and the hippocampus (HPC), and plasma. We found that prophylactic ketamine attenuated learned fear. Eight metabolites were changed in the PFC and HPC upon ketamine treatment. Purine and pyrimidine metabolism were most significantly changed in the HPC, PFC, and, interestingly, plasma of mice two weeks after prophylactic administration. Moreover, most precursors to inhibitory neurotransmitters were increased whereas precursors to excitatory neurotransmitters were decreased. Strikingly, these long-term metabolomic changes were not observed when no stressor was administered. Our results suggest that prophylactic treatment differentially affects purine and pyrimidine metabolism and neurotransmission in brain and plasma following stress, which may underlie the long-lasting resilience to stress induced by a single injection of ketamine. These data may provide novel targets for prophylactic development, and indicate an interaction effect of prophylactic ketamine and stress. To our knowledge, this is the first study that identifies metabolomic alterations and biomarker candidates for prophylactic ketamine efficacy in mice.