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1.
EMBO J ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192032

RESUMO

Glioma cells hijack developmental programs to control cell state. Here, we uncover a glioma cell state-specific metabolic liability that can be therapeutically targeted. To model cell conditions at brain tumor inception, we generated genetically engineered murine gliomas, with deletion of p53 alone (p53) or with constitutively active Notch signaling (N1IC), a pathway critical in controlling astrocyte differentiation during brain development. N1IC tumors harbored quiescent astrocyte-like transformed cell populations while p53 tumors were predominantly comprised of proliferating progenitor-like cell states. Further, N1IC transformed cells exhibited increased mitochondrial lipid peroxidation, high ROS production and depletion of reduced glutathione. This altered mitochondrial phenotype rendered the astrocyte-like, quiescent populations more sensitive to pharmacologic or genetic inhibition of the lipid hydroperoxidase GPX4 and induction of ferroptosis. Treatment of patient-derived early-passage cell lines and glioma slice cultures generated from surgical samples with a GPX4 inhibitor induced selective depletion of quiescent astrocyte-like glioma cell populations with similar metabolic profiles. Collectively, these findings reveal a specific therapeutic vulnerability to ferroptosis linked to mitochondrial redox imbalance in a subpopulation of quiescent astrocyte-like glioma cells resistant to standard forms of treatment.

2.
Blood ; 144(12): 1314-1328, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-38848533

RESUMO

ABSTRACT: The liver plays a crucial role in maintaining systemic iron homeostasis by secreting hepcidin, which is essential for coordinating iron levels in the body. Imbalances in iron homeostasis are associated with various clinical disorders related to iron deficiency or iron overload. Despite the clinical significance, the mechanisms underlying how hepatocytes sense extracellular iron levels to regulate hepcidin synthesis and iron storage are not fully understood. In this study, we identified Foxo1, a well-known regulator of macronutrient metabolism, which translocates to the nucleus of hepatocytes in response to high-iron feeding, holo-transferrin, and bone morphogenetic protein 6 (BMP6) treatment. Furthermore, Foxo1 plays a crucial role in mediating hepcidin induction in response to both iron and BMP signals by directly interacting with evolutionally conserved Foxo binding sites within the hepcidin promoter region. These binding sites were found to colocalize with Smad-binding sites. To investigate the physiological relevance of Foxo1 in iron metabolism, we generated mice with hepatocyte-specific deletion of Foxo1. These mice exhibited reduced hepatic hepcidin expression and serum hepcidin levels, accompanied by elevated serum iron and liver nonheme iron concentrations. Moreover, high-iron diet further exacerbated these abnormalities in iron metabolism in mice lacking hepatic Foxo1. Conversely, hepatocyte-specific Foxo1 overexpression increased hepatic hepcidin expression and serum hepcidin levels, thereby ameliorating iron overload in a murine model of hereditary hemochromatosis (Hfe-/- mice). In summary, our study identifies Foxo1 as a critical regulator of hepcidin and systemic iron homeostasis. Targeting Foxo1 may offer therapeutic opportunities for managing conditions associated with aberrant iron metabolism.


Assuntos
Proteína Forkhead Box O1 , Hepatócitos , Hepcidinas , Homeostase , Ferro , Animais , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Ferro/metabolismo , Hepcidinas/metabolismo , Hepcidinas/genética , Camundongos , Hepatócitos/metabolismo , Humanos , Camundongos Knockout , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Regulação da Expressão Gênica
3.
Eur Heart J ; 45(4): 287-305, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-37992083

RESUMO

BACKGROUND AND AIMS: Stanford type A aortic dissection (AD) is a degenerative aortic remodelling disease marked by an exceedingly high mortality without effective pharmacologic therapies. Smooth muscle cells (SMCs) lining tunica media adopt a range of states, and their transformation from contractile to synthetic phenotypes fundamentally triggers AD. However, the underlying pathomechanisms governing this population shift and subsequent AD, particularly at distinct disease temporal stages, remain elusive. METHODS: Ascending aortas from nine patients undergoing ascending aorta replacement and five individuals undergoing heart transplantation were subjected to single-cell RNA sequencing. The pathogenic targets governing the phenotypic switch of SMCs were identified by trajectory inference, functional scoring, single-cell regulatory network inference and clustering, regulon, and interactome analyses and confirmed using human ascending aortas, primary SMCs, and a ß-aminopropionitrile monofumarate-induced AD model. RESULTS: The transcriptional profiles of 93 397 cells revealed a dynamic temporal-specific phenotypic transition and marked elevation of the activator protein-1 (AP-1) complex, actively enabling synthetic SMC expansion. Mechanistically, tumour necrosis factor signalling enhanced AP-1 transcriptional activity by dampening mitochondrial oxidative phosphorylation (OXPHOS). Targeting this axis with the OXPHOS enhancer coenzyme Q10 or AP-1-specific inhibitor T-5224 impedes phenotypic transition and aortic degeneration while improving survival by 42.88% (58.3%-83.3% for coenzyme Q10 treatment), 150.15% (33.3%-83.3% for 2-week T-5224), and 175.38% (33.3%-91.7% for 3-week T-5224) in the ß-aminopropionitrile monofumarate-induced AD model. CONCLUSIONS: This cross-sectional compendium of cellular atlas of human ascending aortas during AD progression provides previously unappreciated insights into a transcriptional programme permitting aortic degeneration, highlighting a translational proof of concept for an anti-remodelling intervention as an attractive strategy to manage temporal-specific AD by modulating the tumour necrosis factor-OXPHOS-AP-1 axis.


Assuntos
Doenças da Aorta , Dissecção Aórtica , Benzofenonas , Isoxazóis , Doenças Vasculares , Humanos , Fator de Transcrição AP-1 , Aminopropionitrilo , Estudos Transversais , Dissecção Aórtica/genética , Doenças da Aorta/patologia , Doenças Vasculares/patologia , Miócitos de Músculo Liso/patologia , Miócitos de Músculo Liso/fisiologia , Fatores de Necrose Tumoral
4.
BMC Biol ; 22(1): 163, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075492

RESUMO

BACKGROUND: Energy allocation between growth and reproduction determines puberty onset and fertility. In mammals, peripheral hormones such as leptin, insulin and ghrelin signal metabolic information to the higher centres controlling gonadotrophin-releasing hormone neurone activity. However, these observations could not be confirmed in lower vertebrates, suggesting that other factors may mediate the energetic trade-off between growth and reproduction. A bioinformatic and experimental study suggested co-regulation of the circadian clock, reproductive axis and growth-regulating genes in zebrafish. While loss-of-function of most of the identified co-regulated genes had no effect or only had mild effects on reproduction, no such information existed about the co-regulated somatostatin, well-known for its actions on growth and metabolism. RESULTS: We show that somatostatin signalling is pivotal in regulating fecundity and metabolism. Knock-out of zebrafish somatostatin 1.1 (sst1.1) and somatostatin 1.2 (sst1.2) caused a 20-30% increase in embryonic primordial germ cells, and sst1.2-/- adults laid 40% more eggs than their wild-type siblings. The sst1.1-/- and sst1.2-/- mutants had divergent metabolic phenotypes: the former had 25% more pancreatic α-cells, were hyperglycaemic and glucose intolerant, and had increased adipocyte mass; the latter had 25% more pancreatic ß-cells, improved glucose clearance and reduced adipocyte mass. CONCLUSIONS: We conclude that somatostatin signalling regulates energy metabolism and fecundity through anti-proliferative and modulatory actions on primordial germ cells, pancreatic insulin and glucagon cells and the hypothalamus. The ancient origin of the somatostatin system suggests it could act as a switch linking metabolism and reproduction across vertebrates. The results raise the possibility of applications in human and animal fertility.


Assuntos
Metabolismo Energético , Reprodução , Transdução de Sinais , Somatostatina , Peixe-Zebra , Animais , Feminino , Fertilidade , Reprodução/fisiologia , Somatostatina/metabolismo , Somatostatina/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
5.
Pediatr Res ; 95(3): 770-774, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38007519

RESUMO

BACKGROUND: Previous studies have shown that TREM2 plays a protective role in acute lung injury (ALI). This prospective study aimed to investigate the role of sTREM2 as a forecasting factor for ALI in infants after pediatric cardiac surgery undergoing cardiopulmonary bypass (CPB). METHODS: Seventy-five consecutive patients younger than 1 year who underwent cardiac surgery were enrolled in this study. Sixty-one fulfilled the inclusion criteria and had been divided into ALI and non-ALI groups. Children's demographic characteristics and clinical data were collected. Perioperative sTREM2 levels were analyzed at five timepoints. RESULTS: In this study, children in the ALI group were younger, lighter, with higher RACHS-1 scores and underwent significantly longer CPB time. Post-CPB ALI had an impact on clinical outcomes, which contributed to a longer duration of mechanical ventilation, ICU and hospital stay than non-ALI group. Significant differences were manifested off-CPB, 1 h/6 h after CPB, and day 1 after surgery between the two groups. Binary logistic models revealed that off-CPB sTREM2 was significantly associated with the incidence of post-CPB ALI after adjustment. ROC analysis showed that the AUC of off-CPB sTREM2 level was 0.791, and the optimal cutoff value was 788.6 pg/ml. CONCLUSIONS: The off-CPB sTREM2 level was an independent prognostic factor for post-CPB ALI in infants. IMPACT: Plasma sTREM2 works together with downstream TREM2 to regulate inflammation response by binding the receptor to other cells. Previous studies have shown that TREM2 plays a protective role in ischemia-reperfusion and has anti-inflammatory effects on acute lung injury (ALI). This study analyzed the risk factors of post-cardiopulmonary bypass (CPB) ALI. We found that weight and off-CPB sTREM2 level were independent prognostic factors for post-CPB ALI. Plasma sTREM2 may serve as an early biomarker in the prognostic evaluation of acute lung injury after cardiac surgery in infants.


Assuntos
Lesão Pulmonar Aguda , Procedimentos Cirúrgicos Cardíacos , Lactente , Humanos , Criança , Prognóstico , Estudos Prospectivos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Lesão Pulmonar Aguda/diagnóstico , Lesão Pulmonar Aguda/etiologia , Ponte Cardiopulmonar/efeitos adversos
6.
Prev Med ; 189: 108119, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39214335

RESUMO

OBJECTIVE: Oral and esophageal cancers are both upper gastrointestinal cancers that share a number of risk factors. However, most previous risk prediction models only focused on one of these two types of cancer. There is no single model that could predict both cancers simultaneously. Our objective was to develop a model specifically tailored for oral and esophageal cancers. METHODS: From 1996 to 2007, a total of 431,460 subjects aged 20 and older without a history of cancer at baseline were included and were monitored for an average duration of 7.3 years in Taiwan, China. A total of 704 cases of oral and esophageal cancers were detected. We utilized both univariate and multivariate COX regression for screening predictors and constructing the model. We evaluated the goodness of fit of the model based on discriminatory accuracy, Harrell's C-index, and calibration. RESULTS: Finally, we developed a Cox regression model using the twelve most significant variables: age, gender, alcohol consumption, betel chewing, smoking status, history of oral ulceration, educational level, marital status, oropharynx status, family history of nasopharyngeal carcinoma, volume ratio of blood cell, and gamma-glutamyl transferase. The AUC (area under the curve) for the complete model was 0.82. Additionally, the C-index was 0.807 (with a 95 % confidence interval ranging from 0.789 to 0.824) and internal calibration results demonstrated that the model performed well. CONCLUSIONS: This study identified the twelve most significant common risk factors for oral and esophageal cancers and developed a single prediction model that performs well for both types of cancer.

7.
Support Care Cancer ; 32(4): 266, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568470

RESUMO

BACKGROUND: Family caregivers, also known as informal caregivers, are critical for the home care of patients with urostomy. The present study aimed to investigate the benefits of family caregivers in China while taking care of patients with urostomy from a positive perspective. METHODS: A qualitative research design was adopted, with a thematic analysis. The qualitative research software NVivo was used for data analysis. Twenty-two family caregivers of urostomy patients participated in an in-depth interview for 60-90 min. A qualitative analysis was performed using a thematic approach in accordance with the six-stage thematic analysis process reported by Braun and Clarke (2006). RESULTS: The following four benefits were identified: mastering knowledge and skills, promoting self-growth, establishing close family ties, and changing the way of life. Among these four themes, 11 sub-themes were constructed by coders. CONCLUSIONS: This study provides new insights into intervention measures for family caregivers of patients with urostomy, which could play an important role in developing the overall model of family-centered nursing.


Assuntos
Cuidadores , Serviços de Assistência Domiciliar , Humanos , China , Pesquisa Qualitativa , População do Leste Asiático
8.
Nephrology (Carlton) ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39168961

RESUMO

BACKGROUND: Kidney function can be impaired in patients with inflammatory bowel diseases (IBD), including Crohn's diseases (CD) and ulcerative colitis (UC). However, the causal relationship between IBD and chronic kidney diseases (CKD) remains unclear. METHODS: We determined the causal association between IBD and CKD by performing two-sample bidirectional mendelian randomization (MR) analyses. Independent genetic variants were selected as instrumental variables (IVs) of the exposure from open-access genome-wide association studies (GWAS) among European ancestry. IVs-outcome estimates were extracted from three separate GWAS for IBD and two for CKD, respectively. Inverse-variance-weighted model was used as the primary MR method. The pleiotropic effect and heterogeneity were evaluated. For either direction, analyses were performed per outcome database and were subsequently meta-analysed. RESULTS: Genetically predicted IBD was associated with higher risk of CKD (OR: 1.045, 95% CI: 1.016-1.073, P = 0.002) by including 42 344 IBD cases and 229 164 controls. Further analyses showed genetic liability to CD increased the risk of CKD (OR: 1.057, 95% CI: 1.027-1.087, p < 0.001) whereas UC did not (OR: 0.999, 95% CI:0.969-1.031, p = 0.970). In contrast, genetically predicted CKD was not associated with IBD (OR: 1.010, 95% CI: 0.965-1.056, p = 0.676), UC (OR: 1.011, 95% CI: 0.948-1.078, p = 0.746) and CD (OR: 1.024; 95% CI: 0.963-1.089, p = 0.447). CONCLUSIONS: We concluded that CD, but not UC, can increase the risk of CKD causally. CD, but not UC, can increase the risk of chronic kidney disease causally. These findings enhance our understanding of the differential impact of IBD subtypes on CKD. It may be necessary to monitor kidney function regularly in patients with CD.

9.
Am J Emerg Med ; 83: 25-31, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38943709

RESUMO

OBJECTIVE: We aimed to investigate the prognostic factors of pediatric extracorporeal cardiopulmonary resuscitation (ECPR). METHODS: The retrospective study included a total of 77 pediatric cases (7 neonates and 70 children) who underwent ECPR after in-hospital and out-of-hospital cardiac arrest between July 2007 and December 2022. Primary endpoints were complications, while secondary endpoints included all-cause in-hospital mortality. RESULTS: Among the 45 cases experiencing complications, 4 neonates and 41 children had multiple simultaneous complications, primarily neurological issues in 25 cases. Additionally, organ failure occurred in 11 cases, and immunodeficiency was present in two cases. Furthermore, 9 cases experienced bleeding events, and 13 cases showed thrombosis. Patients with complications had lower weight, shorter ECMO durations, and longer CPR durations. Non-survivors had longer CPR durations and shorter durations of ECMO, ICU stay, and mechanical ventilation compared to survivors. Complications were more prevalent in non-survivors, particularly organ failure and bleeding events. CONCLUSION: Weight, CPR duration, and ECMO duration were associated with complications, suggesting areas for treatment optimization. The higher occurrence of complications in non-survivors underscores the importance of early detection and management to improve survival rates. Our findings suggest clinicians consider these factors in prognostic assessments to enhance the effectiveness of ECPR programs.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos , Masculino , Feminino , Oxigenação por Membrana Extracorpórea/métodos , Lactente , China/epidemiologia , Pré-Escolar , Reanimação Cardiopulmonar/métodos , Recém-Nascido , Criança , Parada Cardíaca/terapia , Parada Cardíaca/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/mortalidade , Adolescente
10.
Mol Cell Neurosci ; 124: 103820, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36736750

RESUMO

Small non-coding miRNA act as key regulators of several physiological processes due to their ability to interact with numerous target mRNA within a network. Whilst several miRNA can act in concert to regulate target mRNA expression, miR-146a has emerged as a critical modulator of inflammation by targeting key upstream signalling proteins of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway and reductions in this miRNA have been observed in several neurological and neurodegenerative disorders. However, a targeted assessment of behaviour and neural tissues following the loss of miR-146a has not been documented. In this study, we examined the behavioural and neuroinflammatory phenotype of mice lacking miR-146a to determine the role of this miRNA in neurological function. Adult miR-146a-/- mice displayed no overt developmental phenotype with the exception of enlarged spleens. Behavioural testing revealed a mild but significant reduction in exploratory locomotor activity and increase in anxiety-like behaviour, with no changes in short-term spatial memory, fear conditioning, or sensorimotor gating. In the brain, the lack of miR-146a resulted in a significant compensatory miR-155 expression with no significant changes in expression of the target Interleukin 1 Receptor Associated Kinase (Irak) gene family. Despite these effects on upstream NF-κB mediators, downstream expression of cytokine and chemokine messengers was significantly elevated in miR-146a-/- mice compared to wild-type controls. Moreover, this increase in inflammatory cytokines was observed alongside an induction of oxidative stress, driven in part by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, and included reduced thiol antioxidant concentrations and increased oxidised protein carbonyl concentrations. In female miR-146a mice, this increase in oxidative stress resulted in an increased expression of superoxide dismutase 1 (SOD1). Together, this suggests miR-146a plays a key role in regulating inflammation even in the absence of inflammatory stimuli and reduced levels of this miRNA have the capacity to induce limited behavioural effects whilst exacerbating both inflammation and oxidative stress in the brain.


Assuntos
MicroRNAs , NF-kappa B , Animais , Feminino , Camundongos , Citocinas/metabolismo , Inflamação , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças Neuroinflamatórias , NF-kappa B/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo , Transdução de Sinais
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