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AIMS/HYPOTHESIS: Inflammatory signals and increased prostaglandin synthesis play a role during the development of diabetes. The prostaglandin D2 (PGD2) receptor, GPR44/DP2, is highly expressed in human islets and activation of the pathway results in impaired insulin secretion. The role of GPR44 activation on islet function and survival rate during chronic hyperglycaemic conditions is not known. In this study, we investigate GPR44 inhibition by using a selective GPR44 antagonist (AZ8154) in human islets both in vitro and in vivo in diabetic mice transplanted with human islets. METHODS: Human islets were exposed to PGD2 or proinflammatory cytokines in vitro to investigate the effect of GPR44 inhibition on islet survival rate. In addition, the molecular mechanisms of GPR44 inhibition were investigated in human islets exposed to high concentrations of glucose (HG) and to IL-1ß. For the in vivo part of the study, human islets were transplanted under the kidney capsule of immunodeficient diabetic mice and treated with 6, 60 or 100 mg/kg per day of a GPR44 antagonist starting from the transplantation day until day 4 (short-term study) or day 17 (long-term study) post transplantation. IVGTT was performed on mice at day 10 and day 15 post transplantation. After termination of the study, metabolic variables, circulating human proinflammatory cytokines, and hepatocyte growth factor (HGF) were analysed in the grafted human islets. RESULTS: PGD2 or proinflammatory cytokines induced apoptosis in human islets whereas GPR44 inhibition reversed this effect. GPR44 inhibition antagonised the reduction in glucose-stimulated insulin secretion induced by HG and IL-1ß in human islets. This was accompanied by activation of the Akt-glycogen synthase kinase 3ß signalling pathway together with phosphorylation and inactivation of forkhead box O-1and upregulation of pancreatic and duodenal homeobox-1 and HGF. Administration of the GPR44 antagonist for up to 17 days to diabetic mice transplanted with a marginal number of human islets resulted in reduced fasting blood glucose and lower glucose excursions during IVGTT. Improved glucose regulation was supported by increased human C-peptide levels compared with the vehicle group at day 4 and throughout the treatment period. GPR44 inhibition reduced plasma levels of TNF-α and growth-regulated oncogene-α/chemokine (C-X-C motif) ligand 1 and increased the levels of HGF in human islets. CONCLUSIONS/INTERPRETATION: Inhibition of GPR44 in human islets has the potential to improve islet function and survival rate under inflammatory and hyperglycaemic stress. This may have implications for better survival rate of islets following transplantation.
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Proteínas de Ligação a DNA/metabolismo , Ilhotas Pancreáticas/metabolismo , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/metabolismo , Receptores de Prostaglandina/antagonistas & inibidores , Receptores de Prostaglandina/metabolismo , Fatores de Transcrição/metabolismo , Apoptose/fisiologia , Western Blotting , Morte Celular/fisiologia , Glucose/metabolismo , Humanos , Insulina/metabolismo , Secreção de Insulina/fisiologia , Prostaglandina D2 , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Genome-wide association studies (GWAS) of diseases and traits have found associations to gene regions but not the functional SNP or the gene mediating the effect. Difference in gene regulatory signals can be detected using chromatin immunoprecipitation and next-gen sequencing (ChIP-seq) of transcription factors or histone modifications by aligning reads to known polymorphisms in individual genomes. The aim was to identify such regulatory elements in the human liver to understand the genetics behind type 2 diabetes and metabolic diseases. METHODS: The genome of liver tissue was sequenced using 10X Genomics technology to call polymorphic positions. Using ChIP-seq for two histone modifications, H3K4me3 and H3K27ac, and the transcription factor CTCF, and our established bioinformatics pipeline, we detected sites with significant difference in signal between the alleles. RESULTS: We detected 2329 allele-specific SNPs (AS-SNPs) including 25 associated to GWAS SNPs linked to liver biology, e.g., 4 AS-SNPs at two type 2 diabetes loci. Two hundred ninety-two AS-SNPs were associated to liver gene expression in GTEx, and 134 AS-SNPs were located on 166 candidate functional motifs and most of them in EGR1-binding sites. CONCLUSIONS: This study provides a valuable collection of candidate liver regulatory elements for further experimental validation.
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Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Fígado/metabolismo , Doenças Metabólicas/genética , Alelos , Fator de Ligação a CCCTC/genética , Diabetes Mellitus Tipo 2/patologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Regulação da Expressão Gênica/genética , Genoma Humano/genética , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fígado/patologia , Doenças Metabólicas/patologia , Polimorfismo de Nucleotídeo Único/genética , Sequências Reguladoras de Ácido Nucleico/genéticaRESUMO
Since the discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9) as an attractive target in the treatment of hypercholesterolemia, multiple anti-PCSK9 therapeutic modalities have been pursued in drug development. The objective of this research is to set the stage for the quantitative benchmarking of two anti-PCSK9 pharmacological modality classes, monoclonal antibodies (mAbs) and small interfering RNA (siRNA). To this end, we developed an integrative mathematical model of lipoprotein homeostasis describing the dynamic interplay between PCSK9, LDL-cholesterol (LDL-C), VLDL-cholesterol, HDL-cholesterol (HDL-C), apoB, lipoprotein a [Lp(a)], and triglycerides (TGs). We demonstrate that LDL-C decreased proportionally to PCSK9 reduction for both mAb and siRNA modalities. At marketed doses, however, treatment with mAbs resulted in an additional â¼20% LDL-C reduction compared with siRNA. We further used the model as an evaluation tool and determined that no quantitative differences were observed in HDL-C, Lp(a), TG, or apoB responses, suggesting that the disruption of PCSK9 synthesis would provide no additional effects on lipoprotein-related biomarkers in the patient segment investigated. Predictive model simulations further indicate that siRNA therapies may reach reductions in LDL-C levels comparable to those achieved with mAbs if the current threshold of 80% PCSK9 inhibition via siRNA could be overcome.
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Hipercolesterolemia/sangue , Hipercolesterolemia/metabolismo , Modelos Teóricos , Pró-Proteína Convertase 9/sangue , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais Humanizados/sangue , Apolipoproteínas B/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Humanos , Lipoproteína(a)/sangue , RNA Interferente Pequeno/genética , Triglicerídeos/sangueRESUMO
Purpose To develop, evaluate, and demonstrate the feasibility of a whole-body protocol for simultaneous assessment of tissue-specific insulin-mediated fluorine 18 (18F) fluorodeoxyglucose (FDG) influx rates, tissue depots, and whole-body insulin sensitivity (referred to as the M value). Materials and Methods An integrated positron emission tomography (PET)/magnetic resonance (MR) imaging system combined with hyperinsulinemic euglycemic clamp (HEC) was used. Dynamic whole-body PET imaging was used to determine the insulin-mediated 18F-FDG tissue influx rate (Ki) in the whole-body region by using the Patlak method. M value was determined with the HEC method at PET imaging. Tissue depots were quantified by using water-fat separated MR imaging and manual segmentations. Feasibility of the imaging protocol was demonstrated by using five healthy control participants and five patients with type 2 diabetes. Associations between M value and Ki were studied in multiple tissues by using the Pearson correlation. Results Positive correlations were found between M value and Ki in multiple tissues: the gluteus muscle (r = 0.875; P = .001), thigh muscle (r = 0.903; P , .001), calf muscle (r = 0.825; P = .003), and abdominal visceral adipose tissue (r = 0.820; P = .004). A negative correlation was found in the brain (r = 20.798; P = .006). The MR imaging-based method for quantification of tissue depots was feasible for determining adipose tissue volumes and fat fractions. Conclusion This PET/MR imaging protocol may be feasible for simultaneous assessment of tissue-specific insulin-mediated 18F-FDG influx rates, tissue depots, and M value. © RSNA, 2017 Online supplemental material is available for this article.
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Composição Corporal/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Resistência à Insulina/fisiologia , Tomografia por Emissão de Pósitrons/métodos , Imagem Corporal Total/métodos , Adulto , Idoso , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/metabolismo , Estudos de Viabilidade , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Especificidade de ÓrgãosRESUMO
We assessed glucose uptake in different tissues in type 2 diabetes (T2D), prediabetes, and control subjects to elucidate its impact in the development of whole-body insulin resistance and T2D. Thirteen T2D, 12 prediabetes, and 10 control subjects, matched for age and BMI, underwent OGTT and abdominal subcutaneous adipose tissue (SAT) biopsies. Integrated whole-body 18F-FDG PET and MRI were performed during a hyperinsulinemic euglycemic clamp to asses glucose uptake rate (MRglu) in several tissues. MRglu in skeletal muscle, SAT, visceral adipose tissue (VAT), and liver was significantly reduced in T2D subjects and correlated positively with M-values (r=0.884, r=0.574, r=0.707 and r=0.403, respectively). Brain MRglu was significantly higher in T2D and prediabetes subjects and had a significant inverse correlation with M-values (r=-0.616). Myocardial MRglu did not differ between groups and did not correlate with the M-values. A multivariate model including skeletal muscle, brain and VAT MRglu best predicted the M-values (adjusted r2=0.85). In addition, SAT MRglu correlated with SAT glucose uptake ex vivo (r=0.491). In different stages of the development of T2D, glucose uptake during hyperinsulinemia is elevated in the brain in parallel with an impairment in peripheral organs. Impaired glucose uptake in skeletal muscle and VAT together with elevated glucose uptake in brain were independently associated with whole-body insulin resistance, and these tissue-specific alterations may contribute to T2D development.
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Encéfalo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Resistência à Insulina , Gordura Intra-Abdominal/metabolismo , Músculo Esquelético/metabolismo , Adulto , Idoso , Transporte Biológico , Encéfalo/diagnóstico por imagem , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Feminino , Técnica Clamp de Glucose , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Imagem Corporal TotalRESUMO
AIM: The integrated glucose-insulin (IGI) model is a semi-mechanistic physiological model which can describe the glucose-insulin homeostasis system following various glucose challenge settings. The aim of the present work was to apply the model to a large and diverse population of metformin-only-treated type 2 diabetes mellitus (T2DM) patients and identify patient-specific covariates. METHODS: Data from four clinical studies were pooled, including glucose and insulin concentration-time profiles from T2DM patients on stable treatment with metformin alone following mixed-meal tolerance tests. The data were collected from a wide range of patients with respect to the duration of diabetes and level of glycaemic control. RESULTS: The IGI model was expanded by four patient-specific covariates. The level of glycaemic control, represented by baseline glycosylated haemoglobin was identified as a significant covariate for steady-state glucose, insulin-dependent glucose clearance and the magnitude of the incretin effect, while baseline body mass index was a significant covariate for steady-state insulin levels. In addition, glucose dose was found to have an impact on glucose absorption rate. The developed model was used to simulate glucose and insulin profiles in different groups of T2DM patients, across a range of glycaemic control, and it was found accurately to characterize their response to the standard oral glucose challenge. CONCLUSIONS: The IGI model was successfully applied to characterize differences between T2DM patients across a wide range of glycaemic control. The addition of patient-specific covariates in the IGI model might be valuable for the future development of antidiabetic treatment and for the design and simulation of clinical studies.
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Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Metformina/uso terapêutico , Modelos Biológicos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Glucocorticoid replacement therapy in patients with adrenal insufficiency (AI), whether primary (Addison's disease) or secondary (due to hypopituitarism), has been established for some 50 years. The current standard treatment regimen involves twice- or thrice-daily dosing with a glucocorticoid, most commonly oral hydrocortisone. Based on previous small-scale studies and clinical perception, life expectancy with conventional glucocorticoid replacement therapy has been considered normal, with a low incidence of adverse events. Data from the past 10-15 years, however, have shown that morbidity remains high and life expectancy is reduced. The increased morbidity and decreased life expectancy appear to be due to both increased exposure to cortisol and insufficient cortisol coverage during infections and other stress-related events. This is thought to reflect a failure of treatment to replicate the natural circadian rhythm of cortisol release, together with a failure to identify and deliver individualized cortisol exposure and to manage patients adequately when increased doses are required. The resulting over- or under-treatment may result in Cushing-like symptoms or adrenal crisis, respectively. This review summarizes the morbidity and mortality seen in patients receiving the current standard of care for AI and suggests areas for improvement in glucocorticoid replacement therapy.
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Insuficiência Adrenal/tratamento farmacológico , Glucocorticoides/uso terapêutico , Terapia de Reposição Hormonal/métodos , Resultado do Tratamento , Glucocorticoides/efeitos adversos , Terapia de Reposição Hormonal/efeitos adversos , HumanosRESUMO
CDKN2C/p18 (Cyclin-Dependent Kinase Inhibitor 2C) is a cell growth regulator that controls cell cycle progression and has previously been associated with increased risk for type II diabetes (T2D) and reduced peripheral adipose tissue (AT) storage capacity. This study explored the role of CDKN2C in AT lipid and glucose metabolism in T2D. Expression of CDKN2C and other genes was analyzed by transcriptomics, or real-time PCR in subcutaneous AT (SAT) samples obtained from T2D and control subjects matched for sex, age and BMI and also in paired SAT and omental AT (OAT) samples. Functional studies included adipocyte glucose uptake and lipolysis rates. CRISPR/Cas9 CDKN2C gene knockdown was performed in human preadipocytes to assess adipogenesis. CDKN2C mRNA expression in SAT and OAT was reduced in T2D and obese subjects compared to controls. CDKN2C expression in SAT was inversely correlated with measures of hyperglycemia, insulin resistance and visceral adiposity and positively correlated with expression of genes in several metabolic pathways, including insulin signaling and fatty acid and carbohydrate metabolism. CDKN2C protein was mainly expressed in adipocytes compared to stromal vascular cells, and its gene and protein expression was up-regulated during adipocyte differentiation. Knockdown of CDKN2C did not affect the percentage of differentiating cells compared to wild type cultures. However, CDKN2C knockdown cultures had significantly lower expression of differentiation markers CEBPA, ADIPOQ and FASN and transiently reduced lipid accumulation per adipocyte during differentiation. Our findings suggest that adipose CDKN2C expression might be reduced as a consequence of insulin resistance and obesity, and this can further contribute to impairment of SAT lipid storage.
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Diabetes Mellitus Tipo 2 , Resistência à Insulina , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Inibidor de Quinase Dependente de Ciclina p18/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Lipídeos , Obesidade/genética , Obesidade/metabolismo , Obesidade AbdominalRESUMO
OBJECTIVE: To obtain direct quantifications of glucose turnover, volumes and fat content of several tissues in the development of type 2 diabetes (T2D) using a novel integrated approach for whole-body imaging. DESIGN AND METHODS: Hyperinsulinemic-euglycemic clamps and simultaneous whole-body integrated [18F]FDG-PET/MRI with automated analyses were performed in control (n = 12), prediabetes (n = 16) and T2D (n = 13) subjects matched for age, sex and BMI. RESULTS: Whole-body glucose uptake (Rd) was reduced by approximately 25% in T2D vs control subjects, and partitioning to brain was increased from 3.8% of total Rd in controls to 7.1% in T2D. In liver, subcutaneous AT, thigh muscle, total tissue glucose metabolic rates (MRglu) and their % of total Rd were reduced in T2D compared to control subjects. The prediabetes group had intermediate findings. Total MRglu in heart, visceral AT, gluteus and calf muscle was similar across groups. Whole-body insulin sensitivity assessed as glucose infusion rate correlated with liver MRglu but inversely with brain MRglu. Liver fat content correlated with MRglu in brain but inversely with MRglu in other tissues. Calf muscle fat was inversely associated with MRglu only in the same muscle group. CONCLUSIONS: This integrated imaging approach provides detailed quantification of tissue-specific glucose metabolism. During T2D development, insulin-stimulated glucose disposal is impaired and increasingly shifted away from muscle, liver and fat toward the brain. Altered glucose handling in the brain and liver fat accumulation may aggravate insulin resistance in several organs.
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Tecido Adiposo/diagnóstico por imagem , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Glucose/metabolismo , Hiperinsulinismo/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Estado Pré-Diabético/diagnóstico por imagem , Idoso , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Técnica Clamp de Glucose , Humanos , Resistência à Insulina/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Músculo Esquelético/metabolismo , Tomografia por Emissão de Pósitrons/métodosRESUMO
Inhibition of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase is associated with an increased risk of new-onset type 2 diabetes. We studied the association of genetic or pharmacological HMG-CoA reductase inhibition with plasma and adipose tissue (AT) metabolome and AT metabolic pathways. We also investigated the effects of statin-mediated pharmacological inhibition of HMG-CoA reductase on systemic insulin sensitivity by measuring the HOMA-IR index in subjects with or without statin therapy. The direct effects of simvastatin (20-250 nM) or its active metabolite simvastatin hydroxy acid (SA) (8-30 nM) were investigated on human adipocyte glucose uptake, lipolysis, and differentiation and pancreatic insulin secretion. We observed that the LDL-lowering HMGCR rs12916-T allele was negatively associated with plasma phosphatidylcholines and sphingomyelins, and HMGCR expression in AT was correlated with various metabolic and mitochondrial pathways. Clinical data showed that statin treatment was associated with HOMA-IR index after adjustment for age, sex, BMI, HbA1c, LDL-c levels, and diabetes status in the subjects. Supra-therapeutic concentrations of simvastatin reduced glucose uptake in adipocytes and normalized fatty acid-induced insulin hypersecretion from ß-cells. Our data suggest that inhibition of HMG-CoA reductase is associated with insulin resistance. However, statins have a very mild direct effect on AT and pancreas, hence, other tissues as the liver or muscle appear to be of greater importance.
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CONTEXT: Oral once-daily dual-release hydrocortisone (DR-HC) replacement therapy has demonstrated an improved metabolic profile compared to conventional 3-times-daily (TID-HC) therapy among patients with primary adrenal insufficiency. This effect might be related to a more physiological cortisol profile, but also to a modified pattern of cortisol metabolism. OBJECTIVE: This work aimed to study cortisol metabolism during DR-HC and TID-HC. DESIGN: A randomized, 12-week, crossover study was conducted. INTERVENTION AND PARTICIPANTS: DC-HC and same daily dose of TID-HC were administered to patients with primary adrenal insufficiency (nâ =â 50) vs healthy individuals (nâ =â 124) as controls. MAIN OUTCOME MEASURES: Urinary corticosteroid metabolites were measured by gas chromatography/mass spectrometry at 24-hour urinary collections. RESULTS: Total cortisol metabolites decreased during DR-HC compared to TID-HC (Pâ <â .001) and reached control values (Pâ =â .089). During DR-HC, 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) activity measured by tetrahydrocortisolâ +â 5α-tetrahydrocortisol/tetrahydrocortisone ratio was reduced compared to TID-HC (Pâ <â .05), but remained increased vs controls (Pâ <â .001). 11ß-HSD2 activity measured by urinary free cortisone/free cortisol ratio was decreased with TID-HC vs controls (Pâ <â .01) but normalized with DR-HC (Pâ =â .358). 5α- and 5ß-reduced metabolites were decreased with DR-HC compared to TID-HC. Tetrahydrocortisol/5α-tetrahydrocortisol ratio was increased during both treatments, suggesting increased 5ß-reductase activity. CONCLUSIONS: The urinary cortisol metabolome shows striking abnormalities in patients receiving conventional TID-HC replacement therapy, with increased 11ß-HSD1 activity that may account for the unfavorable metabolic phenotype in primary adrenal insufficiency. Its change toward normalization with DR-HC may mediate beneficial metabolic effects. The urinary cortisol metabolome may serve as a tool to assess optimal cortisol replacement therapy.
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Doença de Addison , Hidrocortisona/farmacocinética , Esteroides/urina , Doença de Addison/tratamento farmacológico , Doença de Addison/metabolismo , Doença de Addison/urina , Adulto , Idoso , Cortisona/metabolismo , Cortisona/urina , Estudos Cross-Over , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Europa (Continente) , Feminino , Humanos , Hidrocortisona/uso terapêutico , Hidrocortisona/urina , Masculino , Metaboloma/efeitos dos fármacos , Pessoa de Meia-Idade , Pregnanos/metabolismo , Pregnanos/urina , Esteroides/metabolismo , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/metabolismo , Tetra-Hidrocortisona/urina , UrináliseRESUMO
Background: Glucocorticoids are among the most commonly prescribed drugs, but there is no biomarker that can quantify their action. The aim of the study was to identify and validate circulating biomarkers of glucocorticoid action. Methods: In a randomized, crossover, single-blind, discovery study, 10 subjects with primary adrenal insufficiency (and no other endocrinopathies) were admitted at the in-patient clinic and studied during physiological glucocorticoid exposure and withdrawal. A randomization plan before the first intervention was used. Besides mild physical and/or mental fatigue and salt craving, no serious adverse events were observed. The transcriptome in peripheral blood mononuclear cells and adipose tissue, plasma miRNAomic, and serum metabolomics were compared between the interventions using integrated multi-omic analysis. Results: We identified a transcriptomic profile derived from two tissues and a multi-omic cluster, both predictive of glucocorticoid exposure. A microRNA (miR-122-5p) that was correlated with genes and metabolites regulated by glucocorticoid exposure was identified (p=0.009) and replicated in independent studies with varying glucocorticoid exposure (0.01 ≤ p≤0.05). Conclusions: We have generated results that construct the basis for successful discovery of biomarker(s) to measure effects of glucocorticoids, allowing strategies to individualize and optimize glucocorticoid therapy, and shedding light on disease etiology related to unphysiological glucocorticoid exposure, such as in cardiovascular disease and obesity. Funding: The Swedish Research Council (Grant 2015-02561 and 2019-01112); The Swedish federal government under the LUA/ALF agreement (Grant ALFGBG-719531); The Swedish Endocrinology Association; The Gothenburg Medical Society; Wellcome Trust; The Medical Research Council, UK; The Chief Scientist Office, UK; The Eva Madura's Foundation; The Research Foundation of Copenhagen University Hospital; and The Danish Rheumatism Association. Clinical trial number: NCT02152553.
Several diseases, including asthma, arthritis, some skin conditions, and cancer, are treated with medications called glucocorticoids, which are synthetic versions of human hormones. These drugs are also used to treat people with a condition call adrenal insufficiency who do not produce enough of an important hormone called cortisol. Use of glucocorticoids is very common, the proportion of people in a given country taking them can range from 0.5% to 21% of the population depending on the duration of the treatment. But, like any medication, glucocorticoids have both benefits and risks: people who take glucocorticoids for a long time have an increased risk of diabetes, obesity, cardiovascular disease, and death. Because of the risks associated with taking glucocorticoids, it is very important for physicians to tailor the dose to each patient's needs. Doing this can be tricky, because the levels of glucocorticoids in a patient's blood are not a good indicator of the medication's activity in the body. A test that can accurately measure the glucocorticoid activity could help physicians personalize treatment and reduce harmful side effects. As a first step towards developing such a test, Chantzichristos et al. identified a potential way to measure glucocorticoid activity in patient's blood. In the experiments, blood samples were collected from ten patients with adrenal insufficiency both when they were on no medication, and when they were taking a glucocorticoid to replace their missing hormones. Next, the blood samples were analyzed to determine which genes were turned on and off in each patient with and without the medication. They also compared small molecules in the blood called metabolites and tiny pieces of genetic material called microRNAs that turn genes on and off. The experiments revealed networks of genes, metabolites, and microRNAs that are associated with glucocorticoid activity, and one microRNA called miR-122-5p stood out as a potential way to measure glucocorticoid activity. To verify this microRNA's usefulness, Chantzichristos et al. looked at levels of miR-122-5p in people participating in three other studies and confirmed that it was a good indicator of the glucocorticoid activity. More research is needed to confirm Chantzichristos et al.'s findings and to develop a test that can be used by physicians to measure glucocorticoid activity. The microRNA identified, miR-122-5p, has been previously linked to diabetes, so studying it further may also help scientists understand how taking glucocorticoids may increase the risk of developing diabetes and related diseases.
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Biomarcadores/metabolismo , Glucocorticoides/farmacologia , Transcriptoma , Tecido Adiposo/metabolismo , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Cross-Over , Estudos Transversais , Dinamarca , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Plasma/metabolismo , Distribuição Aleatória , Escócia , Soro/metabolismo , Método Simples-Cego , Suécia , Adulto JovemRESUMO
In this study a 3D printed capsule designed to break from the physiological pressures in the antropyloric region was evaluated for its ability to deliver the synthetic octapeptide octreotide in beagle dogs when co-formulated with the permeation enhancer sodium caprate. The pressure sensitive capsules were compared to traditional enteric coated hard gelatin capsules and enteric coated tablets. Paracetamol, which is completely absorbed in dogs, was included in the formulations and used as an absorption marker to give information about the in vivo performance of the dosage forms. The pressure sensitive capsules released drug in 50% of the dogs. In the cases where drug was released, there was no difference in octreotide bioavailability or Cmax compared to the enteric coated dosage forms. When comparing all dosage forms, a correlation was seen between paracetamol Cmax and octreotide bioavailability, suggesting that a high drug release rate may be beneficial for peptide absorption when delivered together with sodium caprate.
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Peptídeos , Impressão Tridimensional , Administração Oral , Animais , Disponibilidade Biológica , Cápsulas , Cães , Comprimidos com Revestimento EntéricoRESUMO
Long-chain polyunsaturated fatty acids (LC-PUFAs) influence human health in several areas, including cardiovascular disease, diabetes, fatty liver disease, and cancer. ELOVL2 encodes one of the key enzymes in the in vivo synthesis of LC-PUFAs from their precursors. Variants near ELOVL2 have repeatedly been associated with levels of LC-PUFA-derived metabolites in genome-wide association studies (GWAS), but the mechanisms behind these observations remain poorly defined. In this study, we found that rs953413, located in the first intron of ELOVL2, lies within a functional FOXA and HNF4α cooperative binding site. The G allele of rs953413 increases binding of FOXA1/FOXA2 and HNF4α to an evolutionarily conserved enhancer element, conferring allele-specific upregulation of the rs953413-associated gene ELOVL2. The expression of ELOVL2 was significantly downregulated by both FOXA1 and HNF4α knockdown and CRISPR/Cas9-mediated direct mutation to the enhancer element. Our results suggest that rs953413 regulates LC-PUFAs metabolism by altering ELOVL2 expression through FOXA1/FOXA2 and HNF4α cooperation.
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AZD5718 is a first-in-class small-molecule anti-inflammatory drug with the potential to reduce the residual risk of cardiovascular events after myocardial infarction in patients receiving lipid-lowering statin therapy. Leukotrienes are potent proinflammatory and vasoactive mediators synthesized in leukocytes via 5-lipoxygenase and 5-lipoxygenase-activating protein (FLAP). AZD5718 is a FLAP inhibitor that dose-dependently reduced leukotriene biosynthesis in a first-in-human study. We enrolled 12 healthy men in a randomized, open-label, crossover, single-dose phase 1 pharmacokinetic study of AZD5718 to investigate a potential drug-drug interaction with rosuvastatin, and the effects of formulation and food intake (ClinicalTrials.gov identifier: NCT02963116). Rosuvastatin (10 mg) were absorbed more rapidly when coadministered with AZD5718 (200 mg), probably owing to weak inhibition of hepatic statin uptake, but relative bioavailability was unaffected (geometric least-squares mean ratio [GMR], 100%; 90% confidence interval [CI], 86%-116%). AZD5718 pharmacokinetics were unaffected by coadministration of rosuvastatin. AZD5718 (200 mg) was absorbed less rapidly when formulated as tablets than oral suspension, with reduced relative bioavailability (GMR, 72%; 90%CI, 64%-80%). AZD5718 absorption was slower when 200-mg tablets were taken after a high-fat breakfast than after fasting, but relative bioavailability was unaffected (GMR, 96%; 90%CI, 87%-106%). In post hoc pharmacodynamic simulations, plasma leukotriene B4 levels were inhibited by >90% throughout the day following once-daily AZD5718, regardless of formulation or administration with food. AZD5718 was well tolerated, with no severe or serious adverse events. These data supported the design of a phase 2a efficacy study of AZD5718 in patients with coronary artery disease.
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Inibidores da Proteína Ativadora de 5-Lipoxigenase/farmacocinética , Interações Alimento-Droga , Pirazóis/farmacocinética , Rosuvastatina Cálcica/farmacologia , Inibidores da Proteína Ativadora de 5-Lipoxigenase/administração & dosagem , Inibidores da Proteína Ativadora de 5-Lipoxigenase/farmacologia , Administração Oral , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Interações Medicamentosas , Jejum , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Masculino , Pessoa de Meia-Idade , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Rosuvastatina Cálcica/administração & dosagem , Adulto JovemRESUMO
INTRODUCTION: It remains unclear whether an increased progression rate of chronic kidney disease (CKD) adds predictive information regarding cardiovascular disease (CVD) risk. The aim of this study was to evaluate the association between CKD progression, based on estimated glomerular filtration rate (eGFR) slope estimates and the risk for CVD. METHODS: We compared the updated eGFR slope calculated over multiple overlapping 2-year periods and the updated mean eGFR. Incident CKD subjects were selected from a prevalent population with diabetes (T2DM). Subjects from the UK Clinical Practice Research Data Link GOLD (CPRD) were followed from CKD diagnosis (n = 30,222) until heart failure (HF), myocardial infarction (MI), ischemic stroke (IS), or a composite end point including all 3 event types (MACE plus), mortality, database dropout, or end of study follow-up. RESULTS: Both the updated eGFR slope and updated mean eGFR were associated with MACE plus and HF. Updated eGFR slope decline of > -3 ml/min/1.73 m2 increased the risk for MACE plus (adjusted hazard ratio [HR] = 1.45; 95% confidence interval [CI], 1.26-1.67), HF (HR = 1.50; 95% CI, 1.27-1.76), and MI (HR = 1.39; 95% CI, 1.01-1.91). CONCLUSIONS: This study strongly supports current evidence that CKD is an independent risk factor for CVD. From a clinical perspective, both rate of progression and cumulative status of CKD describe distinct aspects of the cardiorenal risk among persons with diabetes. This evidence is essential to enable more timely and improved use of treatments in this population.
RESUMO
Alteration of various metabolites has been linked to type 2 diabetes (T2D) and insulin resistance. However, identifying significant associations between metabolites and tissue-specific phenotypes requires a multi-omics approach. In a cohort of 42 subjects with different levels of glucose tolerance (normal, prediabetes and T2D) matched for age and body mass index, we calculated associations between parameters of whole-body positron emission tomography (PET)/magnetic resonance imaging (MRI) during hyperinsulinemic euglycemic clamp and non-targeted metabolomics profiling for subcutaneous adipose tissue (SAT) and plasma. Plasma metabolomics profiling revealed that hepatic fat content was positively associated with tyrosine, and negatively associated with lysoPC(P-16:0). Visceral adipose tissue (VAT) and SAT insulin sensitivity (Ki), were positively associated with several lysophospholipids, while the opposite applied to branched-chain amino acids. The adipose tissue metabolomics revealed a positive association between non-esterified fatty acids and, VAT and liver Ki. Bile acids and carnitines in adipose tissue were inversely associated with VAT Ki. Furthermore, we detected several metabolites that were significantly higher in T2D than normal/prediabetes. In this study we present novel associations between several metabolites from SAT and plasma with the fat fraction, volume and insulin sensitivity of various tissues throughout the body, demonstrating the benefit of an integrative multi-omics approach.
Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Resistência à Insulina , Insulina/metabolismo , Estado Pré-Diabético/diagnóstico , Imagem Corporal Total/métodos , Idoso , Aminoácidos de Cadeia Ramificada/metabolismo , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Fluordesoxiglucose F18/administração & dosagem , Fluordesoxiglucose F18/metabolismo , Técnica Clamp de Glucose , Humanos , Gordura Intra-Abdominal/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Lisofosfolipídeos/metabolismo , Imageamento por Ressonância Magnética/métodos , Masculino , Metabolômica , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Estado Pré-Diabético/sangue , Estado Pré-Diabético/metabolismo , Gordura Subcutânea/metabolismoRESUMO
It has been suggested that preoperative fibrinogen plasma concentration is independently associated to postoperative blood loss after cardiac surgery. Theoretically, prophylactic infusion of fibrinogen concentrate may thus reduce postoperative bleeding, but this has not previously been investigated. Twenty elective coronary artery bypass graft (CABG) patients with preoperative plasma fibrinogen levels <3.8 g/l were included in a prospective randomised pilot study. Patients were randomised to receive an infusion of 2 g fibrinogen concentrate (FIB group) or no infusion before surgery (control group). Primary endpoint was safety with clinical adverse events and graft occlusion assessed by multi-slice computed tomography. Predefined secondary endpoints were postoperative blood loss, blood transfusions, haemoglobin levels 24 hours (h) after surgery, and global haemostasis assessed with thromboelastometry, 2 and 24 hours after surgery. Infusion of 2 g fibrinogen concentrate increased plasma levels of fibrinogen by 0.6 +/- 0.2 g/l. There were no clinically detectable adverse events of fibrinogen infusion. Computed tomography revealed one subclinical vein graft occlusion in the FIB group. Fibrinogen concentrate infusion reduced postoperative blood loss by 32% (565 +/- 150 vs. 830 +/- 268 ml/12 h, p=0.010). Haemoglobin concentration was significantly higher 24 h after surgery in the FIB group (110 +/- 12 vs. 98 +/- 8 g/l, p=0.018). Prophylactic fibrinogen concentrate infusion did not influence global postoperative haemostasis as assessed by thromboelastometry. In conclusion, in this pilot study preoperative fibrinogen concentrate infusion reduced bleeding after CABG without evidence of postoperative hypercoagulability. Larger studies are necessary to ensure safety and confirm efficacy of prophylactic fibrinogen treatment in cardiac surgery.
Assuntos
Ponte de Artéria Coronária , Fibrinogênio/administração & dosagem , Hemostáticos/administração & dosagem , Hemorragia Pós-Operatória/tratamento farmacológico , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Transfusão de Sangue , Feminino , Fibrinogênio/efeitos adversos , Fibrinogênio/metabolismo , Oclusão de Enxerto Vascular/induzido quimicamente , Oclusão de Enxerto Vascular/diagnóstico por imagem , Hemoglobinas/metabolismo , Hemostáticos/efeitos adversos , Hemostáticos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Tromboelastografia/efeitos dos fármacos , Tomografia Computadorizada por Raios XRESUMO
Type 2 diabetes (T2D) mellitus is a complex metabolic disease commonly caused by insulin resistance in several tissues. We performed a matched two-dimensional metabolic screening in tissue samples from 43 multi-organ donors. The intra-individual analysis was assessed across five key metabolic tissues (serum, visceral adipose tissue, liver, pancreatic islets and skeletal muscle), and the inter-individual across three different groups reflecting T2D progression. We identified 92 metabolites differing significantly between non-diabetes and T2D subjects. In diabetes cases, carnitines were significantly higher in liver, while lysophosphatidylcholines were significantly lower in muscle and serum. We tracked the primary tissue of origin for multiple metabolites whose alterations were reflected in serum. An investigation of three major stages spanning from controls, to pre-diabetes and to overt T2D indicated that a subset of lysophosphatidylcholines was significantly lower in the muscle of pre-diabetes subjects. Moreover, glycodeoxycholic acid was significantly higher in liver of pre-diabetes subjects while additional increase in T2D was insignificant. We confirmed many previously reported findings and substantially expanded on them with altered markers for early and overt T2D. Overall, the analysis of this unique dataset can increase the understanding of the metabolic interplay between organs in the development of T2D.