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1.
Sci Rep ; 14(1): 11172, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750192

RESUMO

A significant number of pregnancies are lost in the first trimester and 1-2% are ectopic pregnancies (EPs). Early pregnancy loss in general can cause significant morbidity with bleeding or infection, while EPs are the leading cause of maternal mortality in the first trimester. Symptoms of pregnancy loss and EP are very similar (including pain and bleeding); however, these symptoms are also common in live normally sited pregnancies (LNSP). To date, no biomarkers have been identified to differentiate LNSP from pregnancies that will not progress beyond early gestation (non-viable or EPs), defined together as combined adverse outcomes (CAO). In this study, we present a novel machine learning pipeline to create prediction models that identify a composite biomarker to differentiate LNSP from CAO in symptomatic women. This prospective cohort study included 370 participants. A single blood sample was prospectively collected from participants on first emergency presentation prior to final clinical diagnosis of pregnancy outcome: LNSP, miscarriage, pregnancy of unknown location (PUL) or tubal EP (tEP). Miscarriage, PUL and tEP were grouped together into a CAO group. Human chorionic gonadotrophin ß (ß-hCG) and progesterone concentrations were measured in plasma. Serum samples were subjected to untargeted metabolomic profiling. The cohort was randomly split into train and validation data sets, with the train data set subjected to variable selection. Nine metabolite signals were identified as key discriminators of LNSP versus CAO. Random forest models were constructed using stable metabolite signals alone, or in combination with plasma hormone concentrations and demographic data. When comparing LNSP with CAO, a model with stable metabolite signals only demonstrated a modest predictive accuracy (0.68), which was comparable to a model of ß-hCG and progesterone (0.71). The best model for LNSP prediction comprised stable metabolite signals and hormone concentrations (accuracy = 0.79). In conclusion, serum metabolite levels and biochemical markers from a single blood sample possess modest predictive utility in differentiating LNSP from CAO pregnancies upon first presentation, which is improved by variable selection and combination using machine learning. A diagnostic test to confirm LNSP and thus exclude pregnancies affecting maternal morbidity and potentially life-threatening outcomes would be invaluable in emergency situations.


Assuntos
Biomarcadores , Gravidez Ectópica , Humanos , Feminino , Gravidez , Adulto , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/sangue , Biomarcadores/sangue , Estudos Prospectivos , Primeiro Trimestre da Gravidez/sangue , Aprendizado de Máquina , Aborto Espontâneo/diagnóstico , Aborto Espontâneo/sangue , Resultado da Gravidez , Progesterona/sangue , Gonadotropina Coriônica Humana Subunidade beta/sangue , Gonadotropina Coriônica Humana Subunidade beta/metabolismo
2.
bioRxiv ; 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38293093

RESUMO

Background: Elevated choline kinase alpha (ChoK) is observed in most solid tumours including glioblastomas (GBM), yet until recently, inhibitors of ChoK have demonstrated limited efficacy in GBM models. Given that hypoxia is associated with GBM therapy resistance, we hypothesised that tumour hypoxia could be responsible for such limitations. We therefore evaluated in GBM cells, the effect of hypoxia on the function of JAS239, a potent ChoK inhibitor. Methods: Rodent (F98 and 9L) and human (U-87 MG and U-251 MG) GBM cell lines were subjected to 72 hours of hypoxia conditioning and treated with JAS239 for 24 hours. NMR metabolomic measurements and analyses were performed to evaluate the signalling pathways involved. In addition, cell proliferation, cell cycle progression and cell invasion were measured in cell monolayers and 3D spheroids, with or without JAS239 treatment in normoxic or hypoxic cells to assess how hypoxia affects JAS239 function. Results: Hypoxia and JAS239 treatment led to significant changes in the cellular metabolic pathways, specifically the phospholipid and glycolytic pathways associated with a reduction in cell proliferation via induced cell cycle arrest. Interestingly, JAS239 also impaired GBM invasion. However, JAS239 effects were variable depending on the cell line, reflecting the inherent heterogeneity observed in GBMs. Conclusion: Our findings indicate that JAS239 and hypoxia can deregulate cellular metabolism, inhibit proliferation and alter cell invasion. These results may be useful for the design of new therapeutic strategies based on ChoK inhibition that can act on multiple pro-tumorigenic features.

3.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36834818

RESUMO

CBL is rapidly phosphorylated upon insulin receptor activation. Mice whole body CBL depletion improved insulin sensitivity and glucose clearance; however, the precise mechanisms remain unknown. We depleted either CBL or its associated protein SORBS1/CAP independently in myocytes and assessed mitochondrial function and metabolism compared to control cells. CBL- and CAP-depleted cells showed increased mitochondrial mass with greater proton leak. Mitochondrial respiratory complex I activity and assembly into respirasomes were reduced. Proteome profiling revealed alterations in proteins involved in glycolysis and fatty acid degradation. Our findings demonstrate CBL/CAP pathway couples insulin signaling to efficient mitochondrial respiratory function and metabolism in muscle.


Assuntos
Resistência à Insulina , Proteínas Proto-Oncogênicas c-cbl , Animais , Camundongos , Metabolismo Energético , Insulina/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias Musculares/metabolismo , Células Musculares/metabolismo , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Respiração Celular
4.
Sci Rep ; 10(1): 20198, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214628

RESUMO

Sepsis, defined as life-threatening organ dysfunction caused by infection is difficult to distinguish clinically from infection or post-operative inflammation. We hypothesized that in a heterogeneous group of critically ill children, there would be different metabolic profiles between post-operative inflammation, bacterial and viral infection and infection with or without organ dysfunction. 1D 1H nuclear magnetic resonance spectra were acquired in plasma samples from critically ill children. We included children with bacterial (n = 25) and viral infection (n = 30) and controls (n = 58) (elective cardiac surgery without infection). Principal component analysis was used for data exploration and partial least squares discriminant analysis models for the differences between groups. Area under receiver operating characteristic curve (AUC) values were used to evaluate the models. Univariate analysis demonstrated differences between controls and bacterial and viral infection. There was excellent discrimination between bacterial and control (AUC = 0.94), and viral and control (AUC = 0.83), with slightly more modest discrimination between bacterial and viral (AUC = 0.78). There was modest discrimination (AUC = 0.73) between sepsis with organ dysfunction and infection with no organ dysfunction. In critically ill children, NMR metabolomics differentiates well between those with a post-operative inflammation but no infection, and those with infection (bacterial and viral), and between sepsis and infection.


Assuntos
Infecções Bacterianas/diagnóstico , Estado Terminal , Metaboloma/fisiologia , Sepse/diagnóstico , Viroses/diagnóstico , Infecções Bacterianas/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Prognóstico , Sepse/sangue , Viroses/sangue
5.
J Proteome Res ; 19(9): 3652-3667, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32701294

RESUMO

Osteoarthritis is an age-related degenerative musculoskeletal disease characterized by loss of articular cartilage, synovitis, and subchondral bone sclerosis. Osteoarthritis pathogenesis is yet to be fully elucidated with no osteoarthritis-specific biomarkers in clinical use. Ex vivo equine cartilage explants (n = 5) were incubated in tumor necrosis factor-α (TNF-α)/interleukin-1ß (IL-1ß)-supplemented culture media for 8 days, with the media removed and replaced at 2, 5, and 8 days. Acetonitrile metabolite extractions of 8 day cartilage explants and media samples at all time points underwent one-dimensional (1D) 1H nuclear magnetic resonance metabolomic analysis, with media samples also undergoing mass spectrometry proteomic analysis. Within the cartilage, glucose and lysine were elevated following TNF-α/IL-1ß treatment, while adenosine, alanine, betaine, creatine, myo-inositol, and uridine decreased. Within the culture media, 4, 4, and 6 differentially abundant metabolites and 154, 138, and 72 differentially abundant proteins were identified at 1-2, 3-5, and 6-8 days, respectively, including reduced alanine and increased isoleucine, enolase 1, vimentin, and lamin A/C following treatment. Nine potential novel osteoarthritis neopeptides were elevated in the treated media. Implicated pathways were dominated by those involved in cellular movement. Our innovative study has provided insightful information on early osteoarthritis pathogenesis, enabling potential translation for clinical markers and possible new therapeutic targets.


Assuntos
Cartilagem Articular , Osteoartrite , Animais , Cavalos , Interleucina-1beta , Metabolômica , Proteômica , Fator de Necrose Tumoral alfa
6.
Hormones (Athens) ; 15(3): 445-452, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27394708

RESUMO

OBJECTIVE: Heterozygous mutations on the melanocortin-4-receptor gene (MC4R) are the most frequent cause of monogenic obesity. We describe a novel MC4R deletion in a girl with severe early onset obesity, tall stature, pale skin and red hair. CASE REPORT: Clinical and hormonal parameters were evaluated in a girl born full-term by non-consanguineous parents. Her body mass index (BMI) at presentation (3 years) was 30 kg/m2 (z-score: +4.5SDS). By the age of 5.2 years, she exhibited extreme linear growth acceleration and developed hyperinsulinemia. METHODS: Direct sequencing of the MC4R, MC1Rand for the knownFTOsingle nucleotide polymorphism (SNP) rs9939609was performed for the patient and her family. RESULTS: A novel heterozygous MC4R p.Met215del (c.643_645delATG) deletion was identified in the patient, her father and her brother, both of whom exhibited a milder phenotype. 3D structural dynamic simulation studies investigated the conformational changes induced by the p.Met215del. The patient and her mother were also found to be carriers of the obesity risk associated FTOrs9939609SNP. Finally, the identification of the known p.Arg160Trp MC1Rvariant in the patient accounts for the red hair and pale skin phenotypic features. CONCLUSION: The p.Met215del causes global conformational and functional changes as it is localized at the alpha-helical transmembrane regions and the membrane spanning regions of the beta-barrel. This novel mutation produces a severe overgrowth phenotype that is apparent as from infancy and is progressive in childhood. The additional negative effect of environmental and unhealthy lifestyle habits as well as a possible co-interaction of FTOrs9939609 SNP may worsen the phenotype.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Deleção de Genes , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/genética , Idade de Início , Índice de Massa Corporal , Criança , Pré-Escolar , Comportamento Alimentar , Feminino , Predisposição Genética para Doença , Cor de Cabelo/genética , Hereditariedade , Heterozigoto , Humanos , Hiperfagia/genética , Hiperfagia/fisiopatologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Linhagem , Fenótipo , Conformação Proteica , Receptor Tipo 4 de Melanocortina/química , Receptor Tipo 4 de Melanocortina/metabolismo , Índice de Gravidade de Doença , Pigmentação da Pele/genética , Relação Estrutura-Atividade
7.
Am J Med Genet A ; 170(3): 754-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26728615

RESUMO

Steinfeld syndrome (MIM #184705) was first reported in 1982. It is characterised by holoprosencephaly and limb defects, however other anomalies may also be present. Following the initial description, three further cases have been reported in the literature. We report on a 23-year-old girl, with features of microform holoprosencephaly and bilateral congenital elbow dislocation in association with hypoplastic radial heads. She was identified to have a variant in the CDON gene inherited from her father who had ocular hypotelorism, but no other clinical features. We discuss the clinical features of Steinfeld syndrome, and broaden the phenotypic spectrum of this condition. Structural analysis suggests that this variant could lead to destabilisation of binding of CDON with hedgehog proteins. Further work needs to be done to confirm whether mutations in the CDON gene are the cause of Steinfeld syndrome.


Assuntos
Cardiopatias Congênitas/diagnóstico , Holoprosencefalia/diagnóstico , Deformidades Congênitas dos Membros/diagnóstico , Fenótipo , Sequência de Aminoácidos , Encéfalo/patologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Hibridização Genômica Comparativa , Fácies , Feminino , Cardiopatias Congênitas/genética , Heterozigoto , Holoprosencefalia/genética , Humanos , Deformidades Congênitas dos Membros/genética , Imageamento por Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Conformação Proteica , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Adulto Jovem
8.
Clin Endocrinol (Oxf) ; 84(1): 80-4, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26173472

RESUMO

BACKGROUND: The onset of puberty is influenced by the interplay of stimulating and restraining factors, many of which have a genetic origin. Premature activation of the GnRH secretion in central precocious puberty (CPP) may arise either from gain-of-function mutations of the KISS1 and KISS1R genes or from loss-of-function manner mutations of the MKRN3 gene leading to MKRN3 deficiency. OBJECTIVE: To explore the genetic causes responsible for CPP and the potential role of the RING finger protein 3 (MKRN3) gene. DESIGN AND PATIENTS: We investigated potential sequence variations in the intronless MKRN3 gene by Sanger sequencing of the entire 507 amino acid coding region of exon 1 in a family with two affected girls presented with CPP at the age of 6 and 5·7 years, respectively. RESULTS: A novel heterozygous g.Gly312Asp missense mutation in the MKRN3 gene was identified in these siblings. The imprinted MKRN3 missense mutation was also identified as expected in the unaffected father and followed as expected an imprinted mode of inheritance. In silico analysis of the altered missense variant using the computational algorithms Polyphen2, SIFT and Mutation Taster predicted a damage and pathogenic alteration causing CPP. The pathogenicity of the alteration at the protein level via an in silico structural model is also explored. CONCLUSION: A novel mutation in the MKRN3 gene in two sisters with CPP was identified, supporting the fundamental role of this gene in the suppression of the hypothalamic GnRH neurons.


Assuntos
Simulação por Computador , Predisposição Genética para Doença/genética , Mutação de Sentido Incorreto , Puberdade Precoce/genética , Ribonucleoproteínas/genética , Sequência de Aminoácidos , Criança , Pré-Escolar , Análise Mutacional de DNA , Saúde da Família , Feminino , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Ribonucleoproteínas/química , Irmãos , Ubiquitina-Proteína Ligases
9.
Metabolism ; 62(11): 1535-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23890519

RESUMO

Glucokinase (GCK) acts as a glucose sensor and stimulates the release of insulin from pancreatic ß-cells and any GCK gene mutations can lead to different forms of diabetes, such as GCK-monogenic diabetes of the young type 2 (MODY2), permanent neonatal diabetes and congenital hyperinsulinism. Many MODY2 causing mutations display a variation in the degree of severity, ranging from mild dietary-restricted forms to more detrimental presentation requiring insulin replacement. The present study reviews known and two novel GCK mutations in terms of molecular perturbation of the GCK atomic structure but also emphasizes the inactivating and activating properties of the GCK as treatment for T2DM. In silico analysis demonstrated that the newly discovered mutation p.Arg447Pro causes structural conformational changes that lead to the destabilization of the functional properties of the protein resulting in the reduction of glucose and MgATP2- affinity. The novel p.Glu440Stop nonsense mutation on the other hand inactivates the cytoplasmic enzymatic activity of the protein as it is responsible for the loss of the C-terminal end of the polypeptide that includes vital glucose-releasing residues. Based on the in silico models of existing structural data we identified several classes of GCK mutations and discuss their relation to disease outcome. GCK has a central role in controlling body glucose homeostasis and therefore is considered an outstanding drug target for developing new antidiabetic therapies using small molecular activators (GKAs). This study emphasizes the importance in understanding how inactivating and activating GCK mutations affect the mechanistic properties of this glucose sensor. Such information can become the basis for drug discovery of therapeutic compounds and the treatment of T2DM by targeting the GCK allosteric activator site.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucoquinase/genética , Glucoquinase/metabolismo , Hipoglicemiantes/uso terapêutico , Mutação , Arginina , Criança , Códon sem Sentido , Hiperinsulinismo Congênito/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Feminino , Glucoquinase/efeitos dos fármacos , Teste de Tolerância a Glucose , Ácido Glutâmico , Humanos , Hipoglicemiantes/farmacologia , Recém-Nascido , Prolina
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