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1.
Cell ; 151(2): 414-26, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-23063129

RESUMEN

Diabetes, obesity, and cancer affect upward of 15% of the world's population. Interestingly, all three diseases juxtapose dysregulated intracellular signaling with altered metabolic state. Exactly which genetic factors define stable metabolic set points in vivo remains poorly understood. Here, we show that hedgehog signaling rewires cellular metabolism. We identify a cilium-dependent Smo-Ca(2+)-Ampk axis that triggers rapid Warburg-like metabolic reprogramming within minutes of activation and is required for proper metabolic selectivity and flexibility. We show that Smo modulators can uncouple the Smo-Ampk axis from canonical signaling and identify cyclopamine as one of a new class of "selective partial agonists," capable of concomitant inhibition of canonical and activation of noncanonical hedgehog signaling. Intriguingly, activation of the Smo-Ampk axis in vivo drives robust insulin-independent glucose uptake in muscle and brown adipose tissue. These data identify multiple noncanonical endpoints that are pivotal for rational design of hedgehog modulators and provide a new therapeutic avenue for obesity and diabetes.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Glucólisis , Proteínas Hedgehog/metabolismo , Células Musculares/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Quinasas de la Proteína-Quinasa Activada por el AMP , Adipocitos/metabolismo , Animales , Línea Celular , Células Cultivadas , Cilios/metabolismo , Diabetes Mellitus/metabolismo , Humanos , Ratones , Neoplasias/metabolismo , Obesidad/metabolismo , Proteínas Quinasas/metabolismo , Receptor Smoothened
2.
FASEB J ; 36(5): e22320, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35470501

RESUMEN

The cytokine-inducible SH2 domain containing protein (CISH) is the founding member of the suppressor of cytokine signaling (SOCS) family of negative feedback regulators and has been shown to be a physiological regulator of signaling in immune cells. This study sought to investigate novel functions for CISH outside of the immune system. Mice deficient in CISH were generated and analyzed using a range of metabolic and other parameters, including in response to a high fat diet and leptin administration. CISH knockout mice possessed decreased body fat and showed resistance to diet-induced obesity. This was associated with reduced food intake, but unaltered energy expenditure and microbiota composition. CISH ablation resulted in reduced basal expression of the orexigenic Agrp gene in the arcuate nucleus (ARC) region of the brain. Cish was basally expressed in the ARC, with evidence of co-expression with the leptin receptor (Lepr) gene in Agrp-positive neurons. CISH-deficient mice also showed enhanced leptin responsiveness, although Cish expression was not itself modulated by leptin. CISH-deficient mice additionally exhibited improved insulin sensitivity on a high-fat diet, but not glucose tolerance despite reduced body weight. These data identify CISH as an important regulator of homeostasis through impacts on appetite control, mediated at least in part by negative regulation of the anorexigenic effects of leptin, and impacts on glucose metabolism.


Asunto(s)
Adiposidad , Leptina , Proteína Relacionada con Agouti/genética , Proteína Relacionada con Agouti/metabolismo , Animales , Citocinas/metabolismo , Ingestión de Alimentos , Glucosa/metabolismo , Leptina/metabolismo , Ratones , Obesidad/genética , Obesidad/metabolismo , Proteínas Supresoras de la Señalización de Citocinas , Dominios Homologos src
3.
Bipolar Disord ; 25(8): 661-670, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36890661

RESUMEN

OBJECTIVES: The aim of this study was to repurpose a drug for the treatment of bipolar depression. METHODS: A gene expression signature representing the overall transcriptomic effects of a cocktail of drugs widely prescribed to treat bipolar disorder was generated using human neuronal-like (NT2-N) cells. A compound library of 960 approved, off-patent drugs were then screened to identify those drugs that affect transcription most similar to the effects of the bipolar depression drug cocktail. For mechanistic studies, peripheral blood mononuclear cells were obtained from a healthy subject and reprogrammed into induced pluripotent stem cells, which were then differentiated into co-cultured neurons and astrocytes. Efficacy studies were conducted in two animal models of depressive-like behaviours (Flinders Sensitive Line rats and social isolation with chronic restraint stress rats). RESULTS: The screen identified trimetazidine as a potential drug for repurposing. Trimetazidine alters metabolic processes to increase ATP production, which is thought to be deficient in bipolar depression. We showed that trimetazidine increased mitochondrial respiration in cultured human neuronal-like cells. Transcriptomic analysis in induced pluripotent stem cell-derived neuron/astrocyte co-cultures suggested additional mechanisms of action via the focal adhesion and MAPK signalling pathways. In two different rodent models of depressive-like behaviours, trimetazidine exhibited antidepressant-like activity with reduced anhedonia and reduced immobility in the forced swim test. CONCLUSION: Collectively our data support the repurposing of trimetazidine for the treatment of bipolar depression.


Asunto(s)
Trastorno Bipolar , Trimetazidina , Ratas , Humanos , Animales , Trimetazidina/farmacología , Trimetazidina/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/genética , Transcriptoma , Reposicionamiento de Medicamentos , Leucocitos Mononucleares , Modelos Animales de Enfermedad
4.
Artículo en Inglés | MEDLINE | ID: mdl-38072867

RESUMEN

Schizophrenia (SCZ) is a complex neuropsychiatric disorder associated with altered bioenergetic pathways and mitochondrial dysfunction. Antipsychotic medications, both first and second-generation, are commonly prescribed to manage SCZ symptoms, but their direct impact on mitochondrial function remains poorly understood. In this study, we investigated the effects of commonly prescribed antipsychotics on bioenergetic pathways in cultured neurons. We examined the impact of risperidone, aripiprazole, amisulpride, and clozapine on gene expression, mitochondrial bioenergetic profile, and targeted metabolomics after 24-h treatment, using RNA-seq, Seahorse XF24 Flux Analyser, and gas chromatography-mass spectrometry (GC-MS), respectively. Risperidone treatment reduced the expression of genes involved in oxidative phosphorylation, the tricarboxylic acid cycle, and glycolysis pathways, and it showed a tendency to decrease basal mitochondrial respiration. Aripiprazole led to dose-dependent reductions in various mitochondrial function parameters without significantly affecting gene expression. Aripiprazole, amisulpride and clozapine treatment showed an effect on the tricarboxylic acid cycle metabolism, leading to more abundant metabolite levels. Antipsychotic drug effects on mitochondrial function in SCZ are multifaceted. While some drugs have greater effects on gene expression, others appear to exert their effects through enzymatic post-translational or allosteric modification of enzymatic activity. Understanding these effects is crucial for optimising treatment strategies for SCZ. Novel therapeutic interventions targeting energy metabolism by post-transcriptional pathways might be more effective as these can more directly and efficiently regulate energy production.

5.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35806181

RESUMEN

Altered protein synthesis has been implicated in the pathophysiology of several neuropsychiatric disorders, particularly schizophrenia. Ribosomes are the machinery responsible for protein synthesis. However, there remains little information on whether current psychotropic drugs affect ribosomes and contribute to their therapeutic effects. We treated human neuronal-like (NT2-N) cells with amisulpride (10 µM), aripiprazole (0.1 µM), clozapine (10 µM), lamotrigine (50 µM), lithium (2.5 mM), quetiapine (50 µM), risperidone (0.1 µM), valproate (0.5 mM) or vehicle control for 24 h. Transcriptomic and gene set enrichment analysis (GSEA) identified that the ribosomal pathway was altered by these drugs. We found that three of the eight drugs tested significantly decreased ribosomal gene expression, whilst one increased it. Most changes were observed in the components of cytosolic ribosomes and not mitochondrial ribosomes. Protein synthesis assays revealed that aripiprazole, clozapine and lithium all decreased protein synthesis. Several currently prescribed psychotropic drugs seem to impact ribosomal gene expression and protein synthesis. This suggests the possibility of using protein synthesis inhibitors as novel therapeutic agents for neuropsychiatric disorders.


Asunto(s)
Antipsicóticos , Clozapina , Antipsicóticos/farmacología , Antipsicóticos/uso terapéutico , Aripiprazol , Benzodiazepinas/uso terapéutico , Clozapina/uso terapéutico , Humanos , Litio , Olanzapina , Psicotrópicos/farmacología , Psicotrópicos/uso terapéutico , Fumarato de Quetiapina , Ribosomas
6.
FASEB J ; 34(4): 5697-5714, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32141144

RESUMEN

Type 2 diabetes (T2D) manifests from inadequate glucose control due to insulin resistance, hypoinsulinemia, and deteriorating pancreatic ß-cell function. The pro-inflammatory factor Activin has been implicated as a positive correlate of severity in T2D patients, and as a negative regulator of glucose uptake by skeletal muscle, and of pancreatic ß-cell phenotype in mice. Accordingly, we sought to determine whether intervention with the Activin antagonist Follistatin can ameliorate the diabetic pathology. Here, we report that an intravenous Follistatin gene delivery intervention with tropism for striated muscle reduced the serum concentrations of Activin B and improved glycemic control in the db/db mouse model of T2D. Treatment reversed the hyperglycemic progression with a corresponding reduction in the percentage of glycated-hemoglobin to levels similar to lean, healthy mice. Follistatin gene delivery promoted insulinemia and abundance of insulin-positive pancreatic ß-cells, even when treatment was administered to mice with advanced diabetes, supporting a mechanism for improved glycemic control associated with maintenance of functional ß-cells. Our data demonstrate that single-dose intravascular Follistatin gene delivery can ameliorate the diabetic progression and improve prognostic markers of disease. These findings are consistent with other observations of Activin-mediated mechanisms exerting deleterious effects in models of obesity and diabetes, and suggest that interventions that attenuate Activin signaling could help further understanding of T2D and the development of novel T2D therapeutics.


Asunto(s)
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Folistatina/genética , Técnicas de Transferencia de Gen , Terapia Genética , Control Glucémico , Hiperglucemia/terapia , Administración Intravenosa , Animales , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Folistatina/administración & dosificación , Hiperglucemia/genética , Resistencia a la Insulina , Ratones
7.
J Shoulder Elbow Surg ; 30(1): 200-215, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32827653

RESUMEN

BACKGROUND: Rotator cuff tears (RCTs) are a common cause of shoulder disability, yet both conservative and surgical treatment strategies can lead to poor results in some patient populations. Enhanced understanding of the genetic processes associated with RCTs can assist in the development of more effective management options and help predict individual responses to surgical treatment. This systematic review analyzes the current literature on the genetic footprint associated with RCTs and interprets these findings to enhance the current understanding of RCT pathogenesis, potential treatment regimens, and prognostic biomarkers of outcomes after surgical repair. METHODS: A systematic search of the Embase, PubMed, and Web of Science electronic databases was performed. Medical Subject Headings (MeSH) and Emtree index terms were formulated from the concept terms "rotator cuff tear," "genetics," and "human," and synonyms of these concepts were applied to the Web of Science search. Articles were screened against predefined inclusion and exclusion criteria. Eligible studies compared gene expression patterns and genetic polymorphisms between cases (with RCTs) and controls (without RCTs). Quality assessment was performed with studies being rated as high, moderate, or poor quality. A modified best-evidence synthesis was applied, and studies were determined to be of strong, moderate, or limited evidence. RESULTS: The search identified 259 articles. Of these studies, 26 were eligible for review. Two studies were considered poor quality; 15 studies, moderate quality; and 9 studies, high quality. Analysis of these articles found that RCTs were associated with alterations in genes that code for the extracellular matrix, cell apoptosis, immune and inflammatory responses, and growth factor pathways. In particular, there was strong evidence of a significant association between RCTs and the genes MMP3, TNC, and ESRRB. Strong evidence of an association between BMP5 upregulation and successful healing after surgical repair was also found. CONCLUSION: This review provides strong evidence of an genetic association with RCTs. The genotype and gene expression patterns detailed within this review can assist in deciphering the biological mechanisms resulting in RCTs, as well as predicting an individual's response to surgical repair. Future research could investigate whether manipulating these genes-or their associated signaling pathways-could assist in RCT healing and whether genetic biomarkers could be used clinically to predict patient outcomes after surgical repair of RCTs.


Asunto(s)
Lesiones del Manguito de los Rotadores , Artroscopía , Expresión Génica , Humanos , Polimorfismo Genético , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/genética , Lesiones del Manguito de los Rotadores/cirugía , Hombro , Resultado del Tratamiento
8.
Exerc Sport Sci Rev ; 48(3): 110-118, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32568924

RESUMEN

The glucose transporter GLUT4 is critical for skeletal muscle glucose uptake in response to insulin and muscle contraction/exercise. Exercise increases GLUT4 translocation to the sarcolemma and t-tubule and, over the longer term, total GLUT4 protein content. Here, we review key aspects of GLUT4 biology in relation to exercise, with a focus on exercise-induced GLUT4 translocation, postexercise metabolism and muscle insulin sensitivity, and exercise effects on GLUT4 expression.


Asunto(s)
Ejercicio Físico/fisiología , Transportador de Glucosa de Tipo 4/metabolismo , Músculo Esquelético/metabolismo , Animales , Glucosa/metabolismo , Transportador de Glucosa de Tipo 4/genética , Humanos , Resistencia a la Insulina/fisiología , Contracción Muscular/fisiología , Transporte de Proteínas , Sarcolema/metabolismo , Transcripción Genética
9.
Am J Physiol Cell Physiol ; 316(3): C404-C414, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30649921

RESUMEN

Exercise stimulates mitochondrial biogenesis and increases mitochondrial respiratory function and content. However, during high-intensity exercise muscle pH can decrease below pH 6.8 with a concomitant increase in lactate concentration. This drop in muscle pH is associated with reduced exercise-induced mitochondrial biogenesis, while increased lactate may act as a signaling molecule to affect mitochondrial biogenesis. Therefore, in this study we wished to determine the impact of altering pH and lactate concentration in L6 myotubes on genes and proteins known to be involved in mitochondrial biogenesis. We also examined mitochondrial respiration in response to these perturbations. Differentiated L6 myotubes were exposed to normal (pH 7.5)-, low (pH 7.0)-, or high (pH 8.0)-pH media with and without 20 mM sodium l-lactate for 1 and 6 h. Low pH and 20 mM sodium l-lactate resulted in decreased Akt (Ser473) and AMPK (T172) phosphorylation at 1 h compared with controls, while at 6 h the nuclear localization of histone deacetylase 5 (HDAC5) was decreased. When the pH was increased both Akt (Ser473) and AMPK (T172) phosphorylation was increased at 1 h. Overall increased lactate decreased the nuclear content of HDAC5 at 6 h. Exposure to both high- and low-pH media decreased basal mitochondrial respiration, ATP turnover, and maximum mitochondrial respiratory capacity. These data indicate that muscle pH affects several metabolic signaling pathways, including those required for mitochondrial function.


Asunto(s)
Histona Desacetilasas/metabolismo , Mitocondrias/metabolismo , Células Musculares/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Respiración de la Célula/fisiología , Células Cultivadas , Ejercicio Físico/fisiología , Humanos , Concentración de Iones de Hidrógeno , Mitocondrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Biogénesis de Organelos , Fosforilación/fisiología , Transducción de Señal/fisiología
10.
Genet Med ; 21(2): 361-372, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29875422

RESUMEN

PURPOSE: Genotyping CYP2D6 is important for precision drug therapy because the enzyme it encodes metabolizes approximately 25% of drugs, and its activity varies considerably among individuals. Genotype analysis of CYP2D6 is challenging due to its highly polymorphic nature. Over 100 haplotypes (star alleles) have been defined for CYP2D6, some involving a gene conversion with its nearby nonfunctional but highly homologous paralog CYP2D7. We present Stargazer, a new bioinformatics tool that uses next-generation sequencing (NGS) data to call star alleles for CYP2D6 ( https://stargazer.gs.washington.edu/stargazerweb/ ). Stargazer is currently being extended for other pharmacogenes. METHODS: Stargazer identifies star alleles from NGS data by detecting single nucleotide variants, insertion-deletion variants, and structural variants. Stargazer detects structural variation, including gene deletions, duplications, and conversions, by calculating paralog-specific copy numbers from read depths. RESULTS: We applied Stargazer to the NGS data of 32 ethnically diverse HapMap trios that were genotyped by TaqMan assays, long-range polymerase chain reaction, quantitative multiplex polymerase chain reaction, high-resolution melting analysis, and/or Sanger sequencing. CYP2D6 genotyping by Stargazer was 99.0% concordant with the data obtained by these methods, and showed that 28.1% of the samples had structural variation including CYP2D6/CYP2D7 hybrids. CONCLUSION: Accurate genotyping of pharmacogenes with NGS and subsequent allele calling with Stargazer will aid the implementation of precision drug therapy.


Asunto(s)
Alelos , Citocromo P-450 CYP2D6/genética , Técnicas de Genotipaje , Secuenciación de Nucleótidos de Alto Rendimiento , Programas Informáticos , Niño , Biología Computacional , Etnicidad/genética , Padre , Femenino , Haplotipos , Humanos , Internet , Masculino , Madres
11.
Brain Behav Immun ; 82: 309-318, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31493447

RESUMEN

An emerging novel therapeutic agent for major depressive disorder, minocycline, has the potential to influence both gut microbiome and inflammatory status. The present study showed that chronic high fat diet feeding led to changes in both behaviour and the gut microbiome in male mice, without an overt inflammatory response. The diet-induced behavioural changes were characterised as increased immobility in the forced swim test and changes in locomotor activities in the open field test. Minocycline significantly altered the gut microbiome, rendering a community distinctly different to both untreated healthy and diet-affected states. In contrast, minocycline did not reverse high fat diet-induced changes in behaviour.


Asunto(s)
Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Minociclina/farmacología , Animales , Ansiedad/metabolismo , Conducta Animal/fisiología , Depresión/metabolismo , Trastorno Depresivo Mayor/metabolismo , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Microbiota/efectos de los fármacos , Minociclina/metabolismo
12.
Mar Drugs ; 17(11)2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-31652835

RESUMEN

There is an urgent need to discover and develop new anthelmintics for the treatment of parasitic nematodes of veterinary importance to circumvent challenges linked to drug resistant parasites. Being one of the most diverse natural ecosystems, the marine environment represents a rich resource of novel chemical entities. This study investigated 2000 extracts from marine invertebrates, collected from Australian waters, for anthelmintic activity. Using a well-established in vitro bioassay, these extracts were screened for nematocidal activity against Haemonchus contortus-a socioeconomically important parasitic nematode of livestock animals. Extracts (designated Mu-1, Ha-1 and Ha-2) from two marine sponges (Monanchora unguiculata and Haliclona sp.) each significantly affected larvae of H. contortus. Individual extracts displayed a dose-dependent inhibition of both the motility of exsheathed third-stage larvae (xL3s) and the development of xL3s to fourth-stage larvae (L4s). Active fractions in each of the three extracts were identified using bioassay-guided fractionation. From the active fractions from Monanchora unguiculata, a known pentacyclic guanidine alkaloid, fromiamycalin (1), was purified. This alkaloid was shown to be a moderately potent inhibitor of L4 development (half-maximum inhibitory concentration (IC50) = 26.6 ± 0.74 µM) and L4 motility (IC50 = 39.4 ± 4.83 µM), although it had a relatively low potency at inhibiting of xL3 motility (IC50 ≥ 100 µM). Investigation of the active fractions from the two Haliclona collections led to identification of a mixture of amino alcohol lipids, and, subsequently, a known natural product halaminol A (5). Anthelmintic profiling showed that 5 had limited potency at inhibiting larval development and motility. These data indicate that fromiamycalin, other related pentacyclic guanidine alkaloids and/or halaminols could have potential as anthelmintics following future medicinal chemistry efforts.


Asunto(s)
Alcaloides/farmacología , Antihelmínticos/farmacología , Haemonchus/efectos de los fármacos , Alcaloides/química , Animales , Antihelmínticos/química , Australia , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Poríferos/química , Ratas
13.
BMC Musculoskelet Disord ; 20(1): 145, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-30953551

RESUMEN

BACKGROUND: Adhesive capsulitis (AC) is a disabling and poorly understood pathological condition of the shoulder joint. The current study aims to increase our understanding of the pathogenesis, diagnosis and clinical outcomes of people with AC by investigating: 1) transcriptome-wide alterations in gene expression of the glenohumeral joint capsule in people with AC compared to people with non-inflammatory shoulder instability (controls); 2) serum and urine biomarkers to better understand diagnosis and staging of AC; and 3) clinical outcomes in people with AC compared to controls 12-months following arthroscopic capsular release or labral repair respectively. METHODS: The study is a prospective multi-centre longitudinal study investigating people undergoing arthroscopic capsulotomy for AC compared to people undergoing arthroscopic stabilization for shoulder instability. Tissue samples collected from the anterior glenohumeral joint capsule during surgery will undergo RNA-seq to determine differences in gene expression between the study groups. Gene Set Enrichment Analysis will be used to further understand the pathogenesis of AC as well as guide serum and urine biomarker analysis. Clinical outcomes regarding pain, function and quality of life will be assessed using the Oxford Shoulder Score, Oxford Shoulder Instability Score, Quick DASH, American Shoulder and Elbow Society Score, EQ-5D-5 L and active shoulder range of movement. Clinical outcomes will be collected pre-operatively and 12-months post-operatively and study groups will be compared for statistically significant differences using linear regression, adjusting for baseline demographic variables. DISCUSSION: This study will provide much needed information regarding the pathogenesis, diagnosis and staging of AC. It will evaluate clinical outcomes for people undergoing arthroscopic release of AC by comparing this group to people undergoing arthroscopic surgery for shoulder instability. TRIAL REGISTRATION: ACTRN12618000431224 , retrospectively registered 26 March 2018.


Asunto(s)
Artroscopía , Bursitis/diagnóstico , Cápsula Articular/patología , Inestabilidad de la Articulación/diagnóstico , Articulación del Hombro/patología , Adulto , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Bursitis/sangre , Bursitis/cirugía , Bursitis/orina , Diagnóstico Diferencial , Femenino , Perfilación de la Expresión Génica/métodos , Humanos , Inestabilidad de la Articulación/sangre , Inestabilidad de la Articulación/patología , Inestabilidad de la Articulación/orina , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Estudios Observacionales como Asunto , Periodo Posoperatorio , Periodo Preoperatorio , Rango del Movimiento Articular , Articulación del Hombro/fisiología , Resultado del Tratamiento , Adulto Joven
14.
PLoS Genet ; 12(5): e1006033, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27195491

RESUMEN

Type 2 diabetes (T2D) is a complex metabolic disease associated with obesity, insulin resistance and hypoinsulinemia due to pancreatic ß-cell dysfunction. Reduced mitochondrial function is thought to be central to ß-cell dysfunction. Mitochondrial dysfunction and reduced insulin secretion are also observed in ß-cells of humans with the most common human genetic disorder, Down syndrome (DS, Trisomy 21). To identify regions of chromosome 21 that may be associated with perturbed glucose homeostasis we profiled the glycaemic status of different DS mouse models. The Ts65Dn and Dp16 DS mouse lines were hyperglycemic, while Tc1 and Ts1Rhr mice were not, providing us with a region of chromosome 21 containing genes that cause hyperglycemia. We then examined whether any of these genes were upregulated in a set of ~5,000 gene expression changes we had identified in a large gene expression analysis of human T2D ß-cells. This approach produced a single gene, RCAN1, as a candidate gene linking hyperglycemia and functional changes in T2D ß-cells. Further investigations demonstrated that RCAN1 methylation is reduced in human T2D islets at multiple sites, correlating with increased expression. RCAN1 protein expression was also increased in db/db mouse islets and in human and mouse islets exposed to high glucose. Mice overexpressing RCAN1 had reduced in vivo glucose-stimulated insulin secretion and their ß-cells displayed mitochondrial dysfunction including hyperpolarised membrane potential, reduced oxidative phosphorylation and low ATP production. This lack of ß-cell ATP had functional consequences by negatively affecting both glucose-stimulated membrane depolarisation and ATP-dependent insulin granule exocytosis. Thus, from amongst the myriad of gene expression changes occurring in T2D ß-cells where we had little knowledge of which changes cause ß-cell dysfunction, we applied a trisomy 21 screening approach which linked RCAN1 to ß-cell mitochondrial dysfunction in T2D.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Síndrome de Down/genética , Insulina/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Musculares/genética , Adenosina Trifosfato/metabolismo , Aneuploidia , Animales , Proteínas de Unión al Calcio , Cromosomas Humanos Par 21/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Síndrome de Down/metabolismo , Síndrome de Down/patología , Regulación de la Expresión Génica , Glucosa/metabolismo , Humanos , Hiperglucemia/genética , Hiperglucemia/metabolismo , Hiperglucemia/patología , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Mitocondrias/genética , Mitocondrias/patología , Proteínas Musculares/metabolismo , Biosíntesis de Proteínas/genética
15.
Genet Med ; 20(8): 855-866, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29144510

RESUMEN

PURPOSE: As massively parallel sequencing is increasingly being used for clinical decision making, it has become critical to understand parameters that affect sequencing quality and to establish methods for measuring and reporting clinical sequencing standards. In this report, we propose a definition for reduced coverage regions and describe a set of standards for variant calling in clinical sequencing applications. METHODS: To enable sequencing centers to assess the regions of poor sequencing quality in their own data, we optimized and used a tool (ExCID) to identify reduced coverage loci within genes or regions of particular interest. We used this framework to examine sequencing data from 500 patients generated in 10 projects at sequencing centers in the National Human Genome Research Institute/National Cancer Institute Clinical Sequencing Exploratory Research Consortium. RESULTS: This approach identified reduced coverage regions in clinically relevant genes, including known clinically relevant loci that were uniquely missed at individual centers, in multiple centers, and in all centers. CONCLUSION: This report provides a process road map for clinical sequencing centers looking to perform similar analyses on their data.


Asunto(s)
Secuenciación del Exoma/métodos , Análisis de Secuencia de ADN/métodos , Secuenciación Completa del Genoma/métodos , Secuencia de Bases , Mapeo Cromosómico , Exoma , Genoma Humano , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Análisis de Secuencia de ADN/normas , Programas Informáticos
16.
Int J Neuropsychopharmacol ; 21(6): 582-591, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29471411

RESUMEN

Background: Bipolar disorder is a mental health condition with progressive social and cognitive function disturbances. Most patients' treatments are based on polypharmacy, but with no biological basis and little is known of the drugs' interactions. The aim of this study was to analyze the effects of lithium, valproate, quetiapine, and lamotrigine, and the interactions between them, on markers of inflammation, bioenergetics, mitochondrial function, and oxidative stress in neuron-like cells and microglial cells. Methods: Neuron-like cells and lipopolysaccharide-stimulated C8-B4 cells were treated with lithium (2.5 mM), valproate (0.5 mM), quetiapine (0.05 mM), and lamotrigine (0.05 mM) individually and in all possible combinations for 24 h. Twenty cytokines were measured in the media from lipopolysaccharide-stimulated C8-B4 cells. Metabolic flux analysis was used to measure bioenergetics, and real-time PCR was used to measure the expression of mitochondrial function genes in neuron-like cells. The production of superoxide in treated cells was also assessed. Results: The results suggest major inhibitory effects on proinflammatory cytokine release as a therapeutic mechanism of these medications when used in combination. The various combinations of medications also caused overexpression of PGC1α and ATP5A1 in neuron-like cells. Quetiapine appears to have a proinflammatory effect in microglial cells, but this was reversed by the addition of lamotrigine independent of the drug combination. Conclusion: Polypharmacy in bipolar disorder may have antiinflammatory effects on microglial cells as well as effects on mitochondrial biogenesis in neuronal cells.


Asunto(s)
Antimaníacos/farmacología , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/metabolismo , Animales , Línea Celular , Citocinas/metabolismo , Interacciones Farmacológicas , Expresión Génica/efectos de los fármacos , Humanos , Inflamación/metabolismo , Lipopolisacáridos , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Polifarmacia
17.
FASEB J ; 31(6): 2592-2602, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28258188

RESUMEN

Reciprocal regulation of hepatic glycolysis and gluconeogenesis contributes to systemic metabolic homeostasis. Recent evidence from lower order organisms has found that reversible post-translational modification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), particularly acetylation, contributes to the reciprocal regulation of glycolysis/gluconeogenesis. However, whether this occurs in mammalian hepatocytes in vitro or in vivo is unknown. Several proteomics studies have identified 4 lysine residues in critical regions of mammalian GAPDH that are altered by multiple post-translational modifications. In FAO hepatoma cells, mutation of all 4 lysine residues (4K-R GAPDH) to mimic their unmodified state reduced GAPDH glycolytic activity and glycolytic flux and increased gluconeogenic GAPDH activity and glucose production. Hepatic expression of 4K-R GAPDH in mice increased GAPDH gluconeogenic activity and the contribution of gluconeogenesis to endogenous glucose production in the unfed state. Consistent with the increased reliance on the energy-consuming gluconeogenic pathway, plasma free fatty acids and ketones were elevated in mice expressing 4K-R GAPDH, suggesting enhanced lipolysis and hepatic fatty acid oxidation. In normal mice, food withholding and refeeding, as well as hormonal regulators of reciprocal glycolysis/gluconeogenesis, such as insulin, glucagon, and norepinephrine, had no effect on global GAPDH acetylation. However, GAPDH acetylation was reduced in obese and type 2 diabetic db/db mice. These findings show that post-translational modification of GAPDH lysine residues regulates hepatic and systemic metabolism, revealing an unappreciated role for hepatic GAPDH in substrate selection and utilization.-Bond, S. T., Howlett, K. F., Kowalski, G. M., Mason, S., Connor, T., Cooper, A., Streltsov, V., Bruce, C. R., Walder, K. R., McGee, S. L. Lysine post-translational modification of glyceraldehyde-3-phosphate dehydrogenase regulates hepatic and systemic metabolism.


Asunto(s)
Regulación Enzimológica de la Expresión Génica/fisiología , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Hígado/metabolismo , Lisina , Procesamiento Proteico-Postraduccional/fisiología , Secuencia de Aminoácidos , Animales , Clonación Molecular , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/genética , Ratones , Ratas
18.
FASEB J ; 31(10): 4515-4532, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28687609

RESUMEN

As a result of limited classes of anthelmintics and an over-reliance on chemical control, there is a great need to discover new compounds to combat drug resistance in parasitic nematodes. Here, we show that deguelin, a plant-derived rotenoid, selectively and potently inhibits the motility and development of nematodes, which supports its potential as a lead candidate for drug development. Furthermore, we demonstrate that deguelin treatment significantly increases gene transcription that is associated with energy metabolism, particularly oxidative phosphorylation and mitoribosomal protein production before inhibiting motility. Mitochondrial tracking confirmed enhanced oxidative phosphorylation. In accordance, real-time measurements of oxidative phosphorylation in response to deguelin treatment demonstrated an immediate decrease in oxygen consumption in both parasitic (Haemonchus contortus) and free-living (Caenorhabditis elegans) nematodes. Consequently, we hypothesize that deguelin is exerting its toxic effect on nematodes as a modulator of oxidative phosphorylation. This study highlights the dynamic biologic response of multicellular organisms to deguelin perturbation.-Preston, S., Korhonen, P. K., Mouchiroud, L., Cornaglia, M., McGee, S. L., Young, N. D., Davis, R. A., Crawford, S., Nowell, C., Ansell, B. R. E., Fisher, G. M., Andrews, K. T., Chang, B. C. H., Gijs, M. A. M., Sternberg, P. W., Auwerx, J., Baell, J., Hofmann, A., Jabbar, A., Gasser, R. B. Deguelin exerts potent nematocidal activity via the mitochondrial respiratory chain.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Membranas Mitocondriales/efectos de los fármacos , Rotenona/análogos & derivados , Animales , Antihelmínticos/farmacología , Caenorhabditis elegans/genética , Resistencia a Medicamentos/efectos de los fármacos , Transporte de Electrón/efectos de los fármacos , Rotenona/farmacología
19.
Cardiovasc Diabetol ; 16(1): 21, 2017 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-28178970

RESUMEN

BACKGROUND: It is unclear whether obesity and type 2 diabetes (T2D), either alone or in combination, induce left ventricular hypertrophy (LVH) independent of hypertension. In the current study, we provide clarity on this issue by rigorously analysing patient left ventricular (LV) structure via clinical indices and via LV geometric patterns (more commonly used in research settings). Importantly, our sample consisted of hypertensive patients that are routinely screened for LVH via echocardiography and normotensive patients that would normally be deemed low risk with no further action required. METHODS: This cross sectional study comprised a total of 353 Caucasian patients, grouped based on diagnosis of obesity, T2D and hypertension, with normotensive obese patients further separated based on metabolic health. Basic metabolic parameters were collected and LV structure and function were assessed via transthoracic echocardiography. Multivariable logistic and linear regression analyses were used to identify predictors of LVH and diastolic dysfunction. RESULTS: Metabolically healthy normotensive obese patients exhibited relatively low risk of LVH. However, normotensive metabolically non-healthy obese, T2D and obese/T2D patients all presented with reduced normal LV geometry that coincided with increased LV concentric remodelling. Furthermore, normotensive patients presenting with both obesity and T2D had a higher incidence of concentric hypertrophy and grade 3 diastolic dysfunction than normotensive patients with either condition alone, indicating an additive effect of obesity and T2D. Alarmingly these alterations were at a comparable prevalence to that observed in hypertensive patients. Interestingly, assessment of LVPWd, a traditional index of LVH, underestimated the presence of LV concentric remodelling. The implications for which were demonstrated by concentric remodelling and concentric hypertrophy strongly associating with grade 1 and 3 diastolic dysfunction respectively, independent of sex, age and BMI. Finally, pulse pressure was identified as a strong predictor of LV remodelling within normotensive patients. CONCLUSIONS: These findings show that metabolically non-healthy obese, T2D and obese/T2D patients can develop LVH independent of hypertension. Furthermore, that LVPWd may underestimate LV remodelling in these patient groups and that pulse pressure can be used as convenient predictor of hypertrophy status.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Hipertrofia Ventricular Izquierda/epidemiología , Obesidad/epidemiología , Disfunción Ventricular Izquierda/epidemiología , Función Ventricular Izquierda , Remodelación Ventricular , Anciano , Presión Sanguínea , Distribución de Chi-Cuadrado , Comorbilidad , Estudios Transversales , Diabetes Mellitus Tipo 2/diagnóstico , Ecocardiografía Doppler , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/fisiopatología , Incidencia , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Obesidad/diagnóstico , Prevalencia , Medición de Riesgo , Factores de Riesgo , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Victoria/epidemiología , Población Blanca
20.
Diabetes Obes Metab ; 19(7): 936-943, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28155245

RESUMEN

AIM: To determine the effect of Scriptaid, a compound that can replicate aspects of the exercise adaptive response through disruption of the class IIa histone deacetylase (HDAC) corepressor complex, on muscle insulin action in obesity. MATERIALS AND METHODS: Diet-induced obese mice were administered Scriptaid (1 mg/kg) via daily intraperitoneal injection for 4 weeks. Whole-body and skeletal muscle metabolic phenotyping of mice was performed, in addition to echocardiography, to assess cardiac morphology and function. RESULTS: Scriptaid treatment had no effect on body weight or composition, but did increase energy expenditure, supported by increased lipid oxidation, while food intake was also increased. Scriptaid enhanced the expression of oxidative genes and proteins, increased fatty acid oxidation and reduced triglycerides and diacylglycerides in skeletal muscle. Furthermore, ex vivo insulin-stimulated glucose uptake by skeletal muscle was enhanced. Surprisingly, heart weight was reduced in Scriptaid-treated mice and was associated with enhanced expression of genes involved in oxidative metabolism in the heart. Scriptaid also improved indices of both diastolic and systolic cardiac function. CONCLUSION: These data show that pharmacological targeting of the class IIa HDAC corepressor complex with Scriptaid could be used to enhance muscle insulin action and cardiac function in obesity.


Asunto(s)
Cardiotónicos/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Corazón/efectos de los fármacos , Inhibidores de Histona Desacetilasas/uso terapéutico , Hidroxilaminas/uso terapéutico , Músculo Esquelético/efectos de los fármacos , Obesidad/tratamiento farmacológico , Quinolinas/uso terapéutico , Animales , Fármacos Antiobesidad/efectos adversos , Fármacos Antiobesidad/uso terapéutico , Cardiotónicos/efectos adversos , Dieta Alta en Grasa/efectos adversos , Ecocardiografía , Ecocardiografía Doppler , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Histona Desacetilasa 2/antagonistas & inhibidores , Histona Desacetilasa 2/metabolismo , Inhibidores de Histona Desacetilasas/efectos adversos , Hidroxilaminas/efectos adversos , Resistencia a la Insulina , Masculino , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Miocardio/patología , Obesidad/etiología , Obesidad/patología , Obesidad/fisiopatología , Tamaño de los Órganos , Quinolinas/efectos adversos
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