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1.
J Biol Chem ; 300(5): 107244, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556087

RESUMO

Recent interest in the biology and function of peritoneal tissue resident macrophages (pMΦ) has led to a better understanding of their cellular origin, programming, and renewal. The programming of pMΦ is dependent on microenvironmental cues and tissue-specific transcription factors, including GATA6. However, the contribution of microRNAs remains poorly defined. We conducted a detailed analysis of the impact of GATA6 deficiency on microRNA expression in mouse pMΦ. Our data suggest that for many of the pMΦ, microRNA composition may be established during tissue specialization and that the effect of GATA6 knockout is largely unable to be rescued in the adult by exogenous GATA6. The data are consistent with GATA6 modulating the expression pattern of specific microRNAs, directly or indirectly, and including miR-146a, miR-223, and miR-203 established by the lineage-determining transcription factor PU.1, to achieve a differentiated pMΦ phenotype. Lastly, we showed a significant dysregulation of miR-708 in pMΦ in the absence of GATA6 during homeostasis and in response to LPS/IFN-γ stimulation. Overexpression of miR-708 in mouse pMΦ in vivo altered 167 mRNA species demonstrating functional downregulation of predicted targets, including cell immune responses and cell cycle regulation. In conclusion, we demonstrate dependence of the microRNA transcriptome on tissue-specific programming of tissue macrophages as exemplified by the role of GATA6 in pMΦ specialization.


Assuntos
Fator de Transcrição GATA6 , Macrófagos Peritoneais , MicroRNAs , Transcriptoma , Animais , Camundongos , Fator de Transcrição GATA6/metabolismo , Fator de Transcrição GATA6/genética , Regulação da Expressão Gênica , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Especificidade de Órgãos , Proteínas Proto-Oncogênicas , Transativadores/genética , Transativadores/metabolismo
2.
Pharmacoeconomics ; 42(3): 329-341, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38001394

RESUMO

BACKGROUND: Antimicrobial resistance is a growing public health concern. There is a global need to estimate the population-level value of developing new antimicrobials and to ensure the effective use of existing antimicrobials as strategies to counteract antimicrobial resistance. To this aim, population-level value criteria need to be considered alongside conventional value measures. OBJECTIVE: The objective of this study was to develop a novel modelling approach to estimate the value of new antimicrobials, considering the transmission, diversity and enablement elements of STEDI value. METHODS: We developed a population-based mathematical model for the assessment of antimicrobial value considering both prophylactic use of antimicrobials and the treatment of selected serious hospital-acquired infections in hospitals in the USA at a population level. Large-scale clinical and population healthcare data were used to inform a modelling-based analysis assessing the impact of introducing a new antimicrobial compared with continuing with no new antimicrobial, accounting for the transmission, diversity and enablement value of antimicrobial agents. RESULTS: Over a 10-year period, the addition of a new antimicrobial as part of an antimicrobial stewardship strategy in the USA was estimated to result in a proportional reduction of 9.03% in projected antimicrobial resistance levels. This yielded an estimated reduction of $64.3 million in hospitalization costs and a gain of over 153,000 quality-adjusted life-years at an economic value of over $15.4 billion over 10 years. Considering input uncertainty, the estimate of monetary benefit ranged from $11.1 to $21.4 billion. CONCLUSIONS: The use of a new antimicrobial for treatment and prophylactic indications yields considerable clinical and economic benefits including transmission diversity and enablement value. These findings may provide decision makers with important evidence to support investment in new antimicrobials and antimicrobial stewardship policy that address the patient, population and system burden associated with antimicrobial resistance.


Assuntos
Anti-Infecciosos , Infecção Hospitalar , Humanos , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Resistência Microbiana a Medicamentos
3.
J Biol Chem ; 299(12): 105409, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37918802

RESUMO

Maintenance of the proteasome requires oxidative phosphorylation (ATP) and mitigation of oxidative damage, in an increasingly dysfunctional relationship with aging. SLC3A2 plays a role on both sides of this dichotomy as an adaptor to SLC7A5, a transporter of branched-chain amino acids (BCAA: Leu, Ile, Val), and to SLC7A11, a cystine importer supplying cysteine to the synthesis of the antioxidant glutathione. Endurance in mammalian muscle depends in part on oxidation of BCAA; however, elevated serum levels are associated with insulin resistance and shortened lifespans. Intriguingly, the evolution of modern birds (Neoaves) has entailed the purging of genes including SLC3A2, SLC7A5, -7, -8, -10, and SLC1A4, -5, largely removing BCAA exchangers and their interacting Na+/Gln symporters in pursuit of improved energetics. Additional gene purging included mitochondrial BCAA aminotransferase (BCAT2), pointing to reduced oxidation of BCAA and increased hepatic conversion to triglycerides and glucose. Fat deposits are anhydrous and highly reduced, maximizing the fuel/weight ratio for prolonged flight, but fat accumulation in muscle cells of aging humans contributes to inflammation and senescence. Duplications of the bidirectional α-ketoacid transporters SLC16A3, SLC16A7, the cystine transporters SLC7A9, SLC7A11, and N-glycan branching enzymes MGAT4B, MGAT4C in Neoaves suggests a shift to the transport of deaminated essential amino acid, and stronger mitigation of oxidative stress supported by the galectin lattice. We suggest that Alfred Lotka's theory of natural selection as a maximum power organizer (PNAS 8:151,1922) made an unusually large contribution to Neoave evolution. Further molecular analysis of Neoaves may reveal novel rewiring with applications for human health and longevity.


Assuntos
Aves , Evolução Molecular , Longevidade , Animais , Humanos , Aminoácidos de Cadeia Ramificada/metabolismo , Cistina/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Fígado/metabolismo , Longevidade/genética , Aves/genética , Aves/metabolismo , Cadeia Pesada da Proteína-1 Reguladora de Fusão/genética , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Seleção Genética
4.
J Biol Chem ; 299(12): 105416, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37918808

RESUMO

Proteostasis requires oxidative metabolism (ATP) and mitigation of the associated damage by glutathione, in an increasingly dysfunctional relationship with aging. SLC3A2 (4F2hc, CD98) plays a role as a disulfide-linked adaptor to the SLC7A5 and SLC7A11 exchangers which import essential amino acids and cystine while exporting Gln and Glu, respectively. The positions of N-glycosylation sites on SLC3A2 have evolved with the emergence of primates, presumably in synchrony with metabolism. Herein, we report that each of the four sites in SLC3A2 has distinct profiles of Golgi-modified N-glycans. N-glycans at the primate-derived site N381 stabilized SLC3A2 in the galectin-3 lattice against coated-pit endocytosis, while N365, the site nearest the membrane promoted glycolipid-galectin-3 (GL-Lect)-driven endocytosis. Our results indicate that surface retention and endocytosis are precisely balanced by the number, position, and remodeling of N-glycans on SLC3A2. Furthermore, proteomics and functional assays revealed an N-glycan-dependent clustering of the SLC3A2∗SLC7A5 heterodimer with amino-acid/Na+ symporters (SLC1A4, SLC1A5) that balances branched-chain amino acids and Gln levels, at the expense of ATP to maintain the Na+/K+ gradient. In replete conditions, SLC3A2 interactions require Golgi-modified N-glycans at N365D and N381D, whereas reducing N-glycosylation in the endoplasmic reticulum by fluvastatin treatment promoted the recruitment of CD44 and transporters needed to mitigate stress. Thus, SLC3A2 N-glycosylation and Golgi remodeling of the N-glycans have distinct roles in amino acids import for growth, maintenance, and metabolic stresses.


Assuntos
Cadeia Pesada da Proteína-1 Reguladora de Fusão , Transportador 1 de Aminoácidos Neutros Grandes , Estresse Fisiológico , Humanos , Trifosfato de Adenosina/metabolismo , Aminoácidos/metabolismo , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Galectina 3/metabolismo , Glicosilação , Células HeLa , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Polissacarídeos/metabolismo
5.
J Neuroinflammation ; 20(1): 209, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705084

RESUMO

BACKGROUND: In the demyelinating disease multiple sclerosis (MS), chronic-active brain inflammation, remyelination failure and neurodegeneration remain major issues despite immunotherapy. While B cell depletion and blockade/sequestration of T and B cells potently reduces episodic relapses, they act peripherally to allow persistence of chronic-active brain inflammation and progressive neurological dysfunction. N-acetyglucosamine (GlcNAc) is a triple modulator of inflammation, myelination and neurodegeneration. GlcNAc promotes biosynthesis of Asn (N)-linked-glycans, which interact with galectins to co-regulate the clustering/signaling/endocytosis of multiple glycoproteins simultaneously. In mice, GlcNAc crosses the blood brain barrier to raise N-glycan branching, suppress inflammatory demyelination by T and B cells and trigger stem/progenitor cell mediated myelin repair. MS clinical severity, demyelination lesion size and neurodegeneration inversely associate with a marker of endogenous GlcNAc, while in healthy humans, age-associated increases in endogenous GlcNAc promote T cell senescence. OBJECTIVES AND METHODS: An open label dose-escalation mechanistic trial of oral GlcNAc at 6 g (n = 18) and 12 g (n = 16) for 4 weeks was performed in MS patients on glatiramer acetate and not in relapse from March 2016 to December 2019 to assess changes in serum GlcNAc, lymphocyte N-glycosylation and inflammatory markers. Post-hoc analysis examined changes in serum neurofilament light chain (sNfL) as well as neurological disability via the Expanded Disability Status Scale (EDSS). RESULTS: Prior to GlcNAc therapy, high serum levels of the inflammatory cytokines IFNγ, IL-17 and IL-6 associated with reduced baseline levels of a marker of endogenous serum GlcNAc. Oral GlcNAc therapy was safe, raised serum levels and modulated N-glycan branching in lymphocytes. Glatiramer acetate reduces TH1, TH17 and B cell activity as well as sNfL, yet the addition of oral GlcNAc dose-dependently lowered serum IFNγ, IL-17, IL-6 and NfL. Oral GlcANc also dose-dependently reduced serum levels of the anti-inflammatory cytokine IL-10, which is increased in the brain of MS patients. 30% of treated patients displayed confirmed improvement in neurological disability, with an average EDSS score decrease of 0.52 points. CONCLUSIONS: Oral GlcNAc inhibits inflammation and neurodegeneration markers in MS patients despite concurrent immunomodulation by glatiramer acetate. Blinded studies are required to investigate GlcNAc's potential to control residual brain inflammation, myelin repair and neurodegeneration in MS.


Assuntos
Encefalite , Esclerose Múltipla , Humanos , Animais , Camundongos , Acetilglucosamina/uso terapêutico , Interleucina-17 , Acetato de Glatiramer , Interleucina-6 , Esclerose Múltipla/tratamento farmacológico , Inflamação/tratamento farmacológico , Citocinas
6.
Pharmacoeconomics ; 41(12): 1657-1673, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37587392

RESUMO

INTRODUCTION: Antimicrobial resistance remains a serious and growing threat to public health, both globally and in the UK, leading to diminishing effectiveness of antimicrobials. Despite a clear need for new antimicrobials, the clinical pipeline is insufficient, driven by high research and development costs and limited expected returns on investment. To counteract this, National Institute for Health and Care Excellence (NICE) and National Health Service (NHS) England have launched a reimbursement mechanism, de-linked from volume of sales, that aims to reduce economic risk by recognising the broader population-level value of antimicrobials. The objective of this study was to quantify the value of ceftazidime-avibactam for treating gram-negative infections in the UK considering some of these broader value elements unique to antimicrobials. METHODS: A previously developed dynamic disease transmission and cost-effectiveness model was applied to assess the value of introducing ceftazidime-avibactam to UK treatment practice in the management of gram-negative hospital-acquired infections in line with the licenced indications for ceftazidime-avibactam. Model inputs were parameterised using sources aligned to the UK perspective. RESULTS: The introduction of ceftazidime-avibactam into a two-line treatment sequence saved over 2300 lives, leading to a gain of 27,600 life years and 22,000 quality-adjusted life years (QALY) at an additional cost of £17 million, over a ten-year transmission period. Ceftazidime-avibactam was associated with a net monetary benefit of £642 million at willingness to pay threshold of £30,000 per QALY; even at a lower threshold of £20,000 per QALY, the net monetary benefit is £422 million. DISCUSSION: Increasing the diversity of antimicrobial treatments through the introduction of an additional antimicrobial, in this instance ceftazidime-avibactam, was associated with substantial clinical and economic benefits, when considering broader population-level value. Despite revealing considerable benefits, the value of ceftazidime-avibactam is only partially reflected in this analysis. Further efforts are required to fully operationalise the spectrum, transmission, enablement, diversity and insurance (STEDI) value framework and accurately reflect the population-level value of antimicrobials.


Assuntos
Ceftazidima , Infecções por Bactérias Gram-Negativas , Humanos , Ceftazidima/uso terapêutico , Antibacterianos/uso terapêutico , Análise Custo-Benefício , Medicina Estatal , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Reino Unido
7.
Infect Dis Ther ; 12(7): 1891-1905, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37410343

RESUMO

INTRODUCTION: Antimicrobial resistance (AMR) is a major public health threat worldwide. Greece has the highest burden of infections due to antibiotic-resistant bacteria among European Union/European Economic Area (EU/EEA) countries. One of the most serious AMR threats in Greece is hospital-acquired infections (HAIs) with limited treatment options (LTO) caused by resistant gram-negative pathogens. Thus, this study sought to estimate the current AMR burden in Greece and the value of reducing AMR to gram-negative pathogens for the Greek healthcare system. METHODS: The current model was adapted from a previously published and validated model of AMR to investigate the overall and AMR-specific burden of treating the most common HAIs with LTO in Greece and scenarios to demonstrate the benefits associated with reducing AMR levels from a third-party payer perspective. Clinical and economic outcomes were estimated over a 10-year time horizon; life years (LYs) and quality-adjusted life years (QALYs) were calculated over a lifetime (based on the annual number of infections over 10 years) at a willingness-to-pay of €30,000 per QALY gained and a 3.5% discount rate. RESULTS: In Greece, the current AMR levels in HAIs with LTO caused by four gram-negative pathogens account for > 316,000 hospital bed days, €73 million in hospitalisation costs, and > 580,000 LYs and 450,000 QALYs lost over 10 years. The monetary burden is estimated at €13.9 billion. A reduction in current AMR levels by 10-50% results in clinical and economic benefit; 29,264-151,699 bed days may be saved, leading to decreased hospitalisation costs (€6.8 million-€35.3 million) and a gain in LYs (85,328-366,162) and QALYs (67,421-289,331), associated with a monetary benefit of between €2.0 billion and €8.7 billion. CONCLUSION: This study shows the substantial clinical and economic burden AMR represents to the Greek healthcare system and the value that can be achieved by effectively reducing AMR levels.

8.
Front Bioeng Biotechnol ; 11: 1179332, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346792

RESUMO

Tissue Engineering of cartilage has been hampered by the inability of engineered tissue to express native levels of type II collagen in vitro. Inadequate levels of type II collagen are, in part, due to a failure to recapitulate the physiological environment in culture. In this study, we engineered primary rabbit chondrocytes to express a secreted reporter, Gaussia Luciferase, driven by the type II collagen promoter, and applied a Design of Experiments approach to assess chondrogenic differentiation in micronutrient-supplemented medium. Using a Response Surface Model, 240 combinations of micronutrients absent in standard chondrogenic differentiation medium, were screened and assessed for type II collagen promoter-driven Gaussia luciferase expression. While the target of this study was to establish a combination of all micronutrients, alpha-linolenic acid, copper, cobalt, chromium, manganese, molybdenum, vitamins A, E, D and B7 were all found to have a significant effect on type II collagen promoter activity. Five conditions containing all micronutrients predicted to produce the greatest luciferase expression were selected for further study. Validation of these conditions in 3D aggregates identified an optimal condition for type II collagen promoter activity. Engineered cartilage grown in this condition, showed a 170% increase in type II collagen expression (Day 22 Luminescence) and in Young's tensile modulus compared to engineered cartilage in basal media alone.Collagen cross-linking analysis confirmed formation of type II-type II collagen and type II-type IX collagen cross-linked heteropolymeric fibrils, characteristic of mature native cartilage. Combining a Design of Experiments approach and secreted reporter cells in 3D aggregate culture enabled a high-throughput platform that can be used to identify more optimal physiological culture parameters for chondrogenesis.

9.
Infect Dis Ther ; 12(7): 1875-1889, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37341866

RESUMO

INTRODUCTION: Antimicrobial resistance (AMR) is a global public health challenge requiring a global response to which Australia has issued a National Antimicrobial Resistance Strategy. The necessity for continued-development of new effective antimicrobials is required to tackle this immediate health threat is clear, but current market conditions may undervalue antimicrobials. We aimed to estimate the health-economic benefits of reducing AMR levels for drug-resistant gram-negative pathogens in Australia, to inform health policy decision-making. METHODS: A published and validated-dynamic health economic model was adapted to the Australian setting. Over a 10-year time horizon, the model estimates the clinical and economic outcomes associated with reducing current AMR levels, by up to 95%, of three gram-negative pathogens in three hospital-acquired infections, from the perspective of healthcare payers. A willingness-to-pay threshold of AUD$15,000-$45,000 per quality-adjusted life-year (QALY) gained and a 5% discount rate (for costs and benefits) were applied. RESULTS: Over ten years, reducing AMR for gram-negative pathogens in Australia is associated with up to 10,251 life-years and 8924 QALYs gained, 9041 bed-days saved and 6644 defined-daily doses of antibiotics avoided. The resulting savings are estimated to be $10.5 million in hospitalisation costs, and the monetary benefit at up to $412.1 million. DISCUSSION: Our results demonstrate the clinical and economic value of reducing AMR impact in Australia. Of note, since our analysis only considered a limited number of pathogens in the hospital setting only and for a limited number of infection types, the benefits of counteracting AMR are likely to extend well beyond the ones demonstrated here. CONCLUSION: These estimates demonstrate the consequences of failure to combat AMR in the Australian context. The benefits in mortality and health system costs justify consideration of innovative reimbursement schemes to encourage the development and commercialisation of new effective antimicrobials.

11.
Infect Dis Ther ; 12(2): 527-543, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36544074

RESUMO

INTRODUCTION: Hospital-acquired infections (HAIs) and growing antimicrobial resistance (AMR) represent a significant healthcare burden globally. Especially in Greece, HAIs with limited treatment options (LTO) pose a serious threat due to increased morbidity and mortality. This study aimed to estimate the clinical and economic value of introducing a new antibacterial for HAIs with LTO in Greece. METHODS: A previously published and validated dynamic model of AMR was adapted to the Greek setting. The model estimated the clinical and economic outcomes of introducing a new antibacterial for the treatment of HAIs with LTO in Greece. The current treatment pathway was compared with introducing a new antibacterial to the treatment sequence. Outcomes were assessed from a third-party payer perspective, over a 10-year transmission period, with quality-adjusted life years (QALYs) and life years (LYs) gained considered over a lifetime horizon. RESULTS: Over the next 10 years, HAIs with LTO in Greece account for approximately 1.4 million hospital bed days, hospitalisation costs of more than €320 million and a loss of approximately 403,000 LYs (319,000 QALYs). Introduction of the new antibacterial as first-line treatment provided the largest clinical and economic benefit, with savings of up to 93,000 bed days, approximately €21 million in hospitalisation costs and an additional 286,000 LYs (226,000 QALYs) in comparison to the current treatment strategy. The introduction of a new antibacterial was linked to a monetary benefit of €6.8 billion at a willingness to pay threshold of €30,000 over 10 years. CONCLUSION: This study highlights the considerable clinical and economic benefit of introducing a new antibacterial for HAIs with LTO in Greece. This analysis shows the additional benefit when a new antibacterial is introduced to treatment sequences. These findings can be used to inform decision makers to implement policies to ensure timely access to new antibacterial treatments in Greece.


Antimicrobial resistance is a major issue for the Greek healthcare system. The overuse of antibacterial agents contributes to the growing resistance levels, making currently available treatment options less effective. As a result, there is an imperative need to address antimicrobial resistance in Greece. This study developed a mathematical model to investigate the clinical and economic benefits of introducing a new antibacterial to current treatment practice. The model uses regression equations to describe the relationships between inputs and outputs from a published and validated model, which describes the transmission and treatment of infections. The model is used to estimate the impact of a new treatment in Greece, considering differing treatment sequence scenarios. The largest health and financial benefits were seen when a new antibacterial was introduced at first line prior to currently used treatments. Over 10 years, savings of up to 93,000 hospital bed days and €21 million in hospitalisation costs could be achieved, as well as a gain of 286,000 patient life years and 226,000 patient quality-adjusted life years (QALYs), a measure of a patient's quality and length of life, over their remaining lifetime. The introduction of a new antibacterial into the current treatment pathway resulted in an overall monetary benefit of €6.8 billion over 10 years, when additional QALYs are valued at €30,000. This study demonstrates considerable health economic benefits of introducing a new antibacterial in Greece and can help inform decision makers when developing a national action plan to combat resistance and improve access to treatments.

12.
Int J Clin Pharm ; 45(2): 330-341, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36484968

RESUMO

BACKGROUND: Only one head-to-head comparison of advanced treatments in moderately to severely active ulcerative colitis (UC) has been published; therefore, there remains a need for further comparisons. AIM: The relative treatment effects of filgotinib and adalimumab, golimumab, infliximab, tofacitinib, ustekinumab and vedolizumab were estimated using a network meta-analysis (NMA). METHOD: Systematically identified studies (MEDLINE, Embase and Cochrane Library; searched: inception-May 2019, updated November 2020) investigating treatments for moderately to severely active UC were re-evaluated for inclusion in a Bayesian NMA (fixed-effects model). Relative treatment effects were estimated using different permutations of patient population (biologic-naïve or biologic-experienced), treatment phase (induction or maintenance) and outcomes (MCS response/remission or endoscopic mucosal healing). RESULTS: Seventeen trials (13 induction; 9 maintenance) were included in the NMA; 8 treatment networks were constructed. Most targeted therapies were superior to placebo in terms of MCS response/remission and endoscopic mucosal healing; filgotinib 200 mg was similar to most other treatments. Infliximab 5 mg/kg was superior to filgotinib 200 mg (biologic-naïve; induction) for MCS response/remission (mean relative effect, 0.34 [95% credible interval: 0.05, 0.62]). Filgotinib 200 mg was superior to adalimumab 160/80/40 mg for MCS response/remission (biologic-experienced; induction; - 0.75 [- 1.16, - 0.35]), and endoscopic mucosal healing (biologic-naïve; maintenance; - 0.90 [- 1.89, - 0.01]); and to golimumab 50 mg every 4 weeks (biologic-naïve; maintenance; - 0.46 [- 0.94, 0]) for MCS response/remission. CONCLUSION: The current treatment landscape benefits patients with moderately to severely active UC, improving key outcomes; filgotinib 200 mg was similar to current standard of care in most outcomes.


Assuntos
Produtos Biológicos , Colite Ulcerativa , Humanos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Infliximab/uso terapêutico , Adalimumab/uso terapêutico , Metanálise em Rede , Teorema de Bayes
13.
Science ; 378(6615): 68-78, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36201590

RESUMO

Establishing causal links between inherited polymorphisms and cancer risk is challenging. Here, we focus on the single-nucleotide polymorphism rs55705857, which confers a sixfold greater risk of isocitrate dehydrogenase (IDH)-mutant low-grade glioma (LGG). We reveal that rs55705857 itself is the causal variant and is associated with molecular pathways that drive LGG. Mechanistically, we show that rs55705857 resides within a brain-specific enhancer, where the risk allele disrupts OCT2/4 binding, allowing increased interaction with the Myc promoter and increased Myc expression. Mutating the orthologous mouse rs55705857 locus accelerated tumor development in an Idh1R132H-driven LGG mouse model from 472 to 172 days and increased penetrance from 30% to 75%. Our work reveals mechanisms of the heritable predisposition to lethal glioma in ~40% of LGG patients.


Assuntos
Neoplasias Encefálicas , Cromossomos Humanos Par 8 , Glioma , Isocitrato Desidrogenase , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Cromossomos Humanos Par 8/genética , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Camundongos , Mutação , Polimorfismo de Nucleotídeo Único
14.
Front Bioeng Biotechnol ; 10: 825005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685088

RESUMO

Improving the ability of human chondrocytes to proliferate, while maintaining their differentiation potential, has presented a great challenge in cartilage tissue engineering. In this study, human chondrocytes were cultured under four unique growth conditions at physiologic oxygen tension: tissue culture plastic (TCP) only, synoviocyte matrix (SCM)-coated flasks only, SCM-coated flasks with bFGF media supplement, and TCP with bFGF media supplement. The results indicated that, compared to standard TCP, all test conditions showed significantly increased cell expansion rates and an increase in both glycosaminoglycan (GAG) and collagen content during redifferentiation culture. Specifically, the combined SCM + bFGF growth condition showed an additive effect, with an increase of approximately 36% more cells per passage (5-7 days) when compared to the SCM alone. In conclusion, the results of this study demonstrate that bFGF and SCM can be used as supplements to enhance the growth of human chondrocytes both as individual enhancers and as a combined additive.

15.
Nat Aging ; 2(3): 231-242, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35528547

RESUMO

Impaired T cell immunity with aging increases mortality from infectious disease. The branching of Asparagine-linked glycans is a critical negative regulator of T cell immunity. Here we show that branching increases with age in females more than males, in naïve more than memory T cells, and in CD4+ more than CD8+ T cells. Female sex hormones and thymic output of naïve T cells (TN) decrease with age, however neither thymectomy nor ovariectomy altered branching. Interleukin-7 (IL-7) signaling was increased in old female more than male mouse TN cells, and triggered increased branching. N-acetylglucosamine, a rate-limiting metabolite for branching, increased with age in humans and synergized with IL-7 to raise branching. Reversing elevated branching rejuvenated T cell function and reduced severity of Salmonella infection in old female mice. These data suggest sex-dimorphic antagonistic pleiotropy, where IL-7 initially benefits immunity through TN maintenance but inhibits TN function by raising branching synergistically with age-dependent increases in N-acetylglucosamine.


Assuntos
Acetilglucosamina , Linfócitos T CD8-Positivos , Humanos , Masculino , Feminino , Animais , Camundongos , Interleucina-7 , Envelhecimento , Polissacarídeos
16.
Anticancer Agents Med Chem ; 22(8): 1611-1621, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515014

RESUMO

BACKGROUND: Chronic inflammation plays a crucial role in the initiation, promotion, and invasion of tumors, and thus the antiproliferative effects of numerous anti-inflammatory drugs have been frequently reported in the literature. Upregulation of the pro-inflammatory enzyme cyclooxygenase-2 (COX-2) has been linked to various human cancers, including breast cancer. OBJECTIVES: This research aims to investigate the antiproliferative activity of different Non-steroidal anti-inflammatory drugs (NSAIDs), including COX-2 selective and non-selective agents, against various breast cancer cell lines and to elucidate possible molecular pathways involved in their activity. METHODS: The antiproliferative and combined effects of NSAIDs with raloxifene were evaluated by MTT assay. Cell migration was assessed using a wound-healing assay. The mechanism of cell death was determined using the Annexin V-FITC/ propidium iodide staining flow cytometry method. A mass spectrometry-based targeted metabolomics approach was used to profile the metabolomic changes induced in the T47d cells upon drug treatment. RESULTS: Our results have demonstrated that celecoxib, a potent and selective COX-2 inhibitor, resulted in significant antiproliferative activity against all examined breast cancer cell lines with IC50 values of 95.44, 49.50. and 97.70 µM against MDA-MB-231, T47d, and MCF-7, respectively. Additionally, celecoxib exhibited a synergistic effect against T47d cells combined with raloxifene, a selective estrogen receptor modulator. Interestingly, celecoxib treatment increased cell apoptosis and resulted in substantial inhibition of cancer cell migration. In addition, the metabolomic analysis suggests that celecoxib may have affected metabolites (n = 43) that are involved in several pathways, including the tricarboxylic acid cycle, amino acids metabolism pathways, and energy production pathways in cancer cells. CONCLUSION: Celecoxib may possess potential therapeutic utility for breast cancer treatment as monotherapy or in combination therapy. The reported metabolic changes taking place upon celecoxib treatment may shed light on possible molecular targets mediating the antiproliferative activity of celecoxib in an independent manner of its COX-2 inhibition.


Assuntos
Neoplasias da Mama , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose , Neoplasias da Mama/patologia , Celecoxib/farmacologia , Proliferação de Células , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Feminino , Humanos , Metabolômica , Cloridrato de Raloxifeno/uso terapêutico
17.
JAMA Neurol ; 78(7): 842-852, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33970182

RESUMO

Importance: N-glycan branching modulates cell surface receptor availability, and its deficiency in mice promotes inflammatory demyelination, reduced myelination, and neurodegeneration. N-acetylglucosamine (GlcNAc) is a rate-limiting substrate for N-glycan branching, but, to our knowledge, endogenous serum levels in patients with multiple sclerosis (MS) are unknown. Objective: To investigate a marker of endogenous serum GlcNAc levels in patients with MS. Design, Setting, and Participants: A cross-sectional discovery study and cross-sectional confirmatory study were conducted at 2 academic MS centers in the US and Germany. The discovery study recruited 54 patients with MS from an outpatient clinic as well as 66 healthy controls between April 20, 2010, and June 21, 2013. The confirmatory study recruited 180 patients with MS from screening visits at an academic MS study center between April 9, 2007, and February 29, 2016. Serum samples were analyzed from December 2, 2013, to March 2, 2015. Statistical analysis was performed from February 23, 2020, to March 18, 2021. Main Outcomes and Measures: Serum levels of GlcNAc plus its stereoisomers, termed N-acetylhexosamine (HexNAc), were assessed using targeted tandem mass spectroscopy. Secondary outcomes (confirmatory study) comprised imaging and clinical disease markers. Results: The discovery cohort included 66 healthy controls (38 women; mean [SD] age, 42 [20] years), 33 patients with relapsing-remitting MS (RRMS; 25 women; mean [SD] age, 50 [11] years), and 21 patients with progressive MS (PMS; 14 women; mean [SD] age, 55 [7] years). The confirmatory cohort included 125 patients with RRMS (83 women; mean [SD] age, 40 [9] years) and 55 patients with PMS (22 women; mean [SD] age, 49 [80] years). In the discovery cohort, the mean (SD) serum level of GlcNAc plus its stereoisomers (HexNAc) was 710 (174) nM in healthy controls and marginally reduced in patients with RRMS (mean [SD] level, 682 [173] nM; P = .04), whereas patients with PMS displayed markedly reduced levels compared with healthy controls (mean [SD] level, 548 [101] nM; P = 9.55 × 10-9) and patients with RRMS (P = 1.83 × 10-4). The difference between patients with RRMS (mean [SD] level, 709 [193] nM) and those with PMS (mean [SD] level, 405 [161] nM; P = 7.6 × 10-18) was confirmed in the independent confirmatory cohort. Lower HexNAc serum levels correlated with worse expanded disability status scale scores (ρ = -0.485; P = 4.73 × 10-12), lower thalamic volume (t = 1.7; P = .04), and thinner retinal nerve fiber layer (B = 0.012 [SE = 7.5 × 10-11]; P = .008). Low baseline serum HexNAc levels correlated with a greater percentage of brain volume loss at 18 months (t = 1.8; P = .04). Conclusions and Relevance: This study suggests that deficiency of GlcNAc plus its stereoisomers (HexNAc) may be a biomarker for PMS. Previous preclinical, human genetic, and ex vivo human mechanistic studies revealed that N-glycan branching and/or GlcNAc may reduce proinflammatory responses, promote myelin repair, and decrease neurodegeneration. Combined, the data suggest that GlcNAc deficiency may be associated with progressive disease and neurodegeneration in patients with MS.


Assuntos
Acetilglucosamina/sangue , Esclerose Múltipla Crônica Progressiva/sangue , Doenças Neurodegenerativas/sangue , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
18.
J Exp Clin Cancer Res ; 40(1): 139, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33894774

RESUMO

BACKGROUND: Glioblastomas stem-like cells (GSCs) by invading the brain parenchyma, remains after resection and radiotherapy and the tumoral microenvironment become stiffer. GSC invasion is reported as stiffness sensitive and associated with altered N-glycosylation pattern. Glycocalyx thickness modulates integrins mechanosensing, but details remain elusive and glycosylation enzymes involved are unknown. Here, we studied the association between matrix stiffness modulation, GSC migration and MGAT5 induced N-glycosylation in fibrillar 3D context. METHOD: To mimic the extracellular matrix fibrillar microenvironments, we designed 3D-ex-polyacrylonitrile nanofibers scaffolds (NFS) with adjustable stiffnesses by loading multiwall carbon nanotubes (MWCNT). GSCs neurosphere were plated on NFSs, allowing GSCs migration and MGAT5 was deleted using CRISPR-Cas9. RESULTS: We found that migration of GSCs was maximum at 166 kPa. Migration rate was correlated with cell shape, expression and maturation of focal adhesion (FA), Epithelial to Mesenchymal Transition (EMT) proteins and (ß1,6) branched N-glycan binding, galectin-3. Mutation of MGAT5 in GSC inhibited N-glycans (ß1-6) branching, suppressed the stiffness dependence of migration on 166 kPa NFS as well as the associated FA and EMT protein expression. CONCLUSION: MGAT5 catalysing multibranched N-glycans is a critical regulators of stiffness induced invasion and GSCs mechanotransduction, underpinning MGAT5 as a serious target to treat cancer.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Encefálicas/patologia , Movimento Celular/fisiologia , Glioblastoma/patologia , Humanos , Células-Tronco Neoplásicas/patologia , Fenótipo
19.
Cancer Res ; 81(10): 2625-2635, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33602786

RESUMO

Aberrant N-glycan Golgi remodeling and metabolism are associated with epithelial-mesenchymal transition (EMT) and metastasis in patients with breast cancer. Despite this association, the N-glycosylation pathway has not been successfully targeted in cancer. Here, we show that inhibition of the mevalonate pathway with fluvastatin, a clinically approved drug, reduces both N-glycosylation and N-glycan-branching, essential components of the EMT program and tumor metastasis. This indicates novel cross-talk between N-glycosylation at the endoplasmic reticulum (ER) and N-glycan remodeling at the Golgi. Consistent with this cooperative model between the two spatially separated levels of protein N-glycosylation, fluvastatin-induced tumor cell death was enhanced by loss of Golgi-associated N-acetylglucosaminyltransferases MGAT1 or MGAT5. In a mouse model of postsurgical metastatic breast cancer, adjuvant fluvastatin treatment reduced metastatic burden and improved overall survival. Collectively, these data support the immediate repurposing of fluvastatin as an adjuvant therapeutic to combat metastatic recurrence in breast cancer by targeting protein N-glycosylation at both the ER and Golgi. SIGNIFICANCE: These findings show that metastatic breast cancer cells depend on the fluvastatin-sensitive mevalonate pathway to support protein N-glycosylation, warranting immediate clinical testing of fluvastatin as an adjuvant therapy for breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Fluvastatina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Ácido Mevalônico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adjuvantes Imunológicos/farmacologia , Animais , Apoptose , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal , Feminino , Glicosilação , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos SCID , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Front Bioeng Biotechnol ; 8: 590743, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33282851

RESUMO

Cartilage tissue has been recalcitrant to tissue engineering approaches. In this study, human chondrocytes were formed into self-assembled cartilage sheets, cultured in physiologic (5%) and atmospheric (20%) oxygen conditions and underwent biochemical, histological and biomechanical analysis at 1- and 2-months. The results indicated that sheets formed at physiological oxygen tension were thicker, contained greater amounts of glycosaminoglycans (GAGs) and type II collagen, and had greater compressive and tensile properties than those cultured in atmospheric oxygen. In all cases, cartilage sheets stained throughout for extracellular matrix components. Type II-IX-XI collagen heteropolymer formed in the neo-cartilage and fibrils were stabilized by trivalent pyridinoline cross-links. Collagen cross-links were not significantly affected by oxygen tension but increased with time in culture. Physiological oxygen tension and longer culture periods both served to increase extracellular matrix components. The foremost correlation was found between compressive stiffness and the GAG to collagen ratio.

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