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1.
Diabetes Obes Metab ; 26(5): 1941-1949, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38379002

RESUMO

AIMS: To investigate the pharmacokinetic/pharmacodynamic properties of once-weekly insulin icodec in individuals with type 1 diabetes (T1D). MATERIALS AND METHODS: In this randomized, open-label, two-period crossover trial, 66 individuals with T1D (age 18-64 years; glycated haemoglobin ≤75 mmol/mol [≤ 9%]) were to receive once-weekly icodec (8 weeks) and once-daily insulin glargine U100 (2 weeks) at individualized fixed equimolar total weekly doses established during up to 10 weeks' run-in with glargine U100 titrated to pre-breakfast plasma glucose (PG) of 4.4-7.2 mmol/L (80-130 mg/dL). Insulin aspart was used as bolus insulin. Blood sampling for icodec pharmacokinetics was performed from the first icodec dose until 35 days after the last dose. The glucose infusion rate at steady state was assessed in glucose clamps (target 6.7 mmol/L [120 mg/dL]) at 16-52 h and 138-168 h after the last icodec dose and 0-24 h after the last glargine U100 dose. Icodec pharmacodynamics during 1 week were predicted by pharmacokinetic-pharmacodynamic modelling. Hypoglycaemia was recorded during the treatment periods based on self-measured PG. RESULTS: Icodec reached pharmacokinetic steady state on average within 2-3 weeks. At steady state, model-predicted daily proportions of glucose infusion rate during the 1-week dosing interval were 14.3%, 19.6%, 18.3%, 15.7%, 13.1%, 10.6% and 8.4%, respectively. Rates and duration of Level 2 hypoglycaemic episodes (PG <3.0 mmol/L [54 mg/dL]) were 32.8 versus 23.9 episodes per participant-year of exposure and 33 ± 25 versus 30 ± 18 min (mean ± SD) for icodec versus glargine U100. CONCLUSIONS: The pharmacokinetic/pharmacodynamic properties of icodec suggest its potential to provide basal coverage in a basal-bolus insulin regimen in people with T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Hipoglicemia , Insulina de Ação Prolongada , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina Glargina/efeitos adversos , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Glicemia , Glucose/uso terapêutico
2.
Diabetes Obes Metab ; 25(12): 3716-3723, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37694740

RESUMO

AIMS: To characterize the pharmacokinetic and pharmacodynamic properties of once-weekly insulin icodec in type 2 diabetes (T2D). MATERIALS AND METHODS: In an open-label trial, 46 individuals with T2D (18-75 years; body mass index 18.0-38.0 kg/m2 ; glycated haemoglobin ≤75 mmol/mol [≤9%]; basal insulin-treated) received subcutaneous once-weekly icodec for ≥8 weeks at individualized doses, aiming at a pre-breakfast plasma glucose concentration of 4.4 to 7.0 mmol/L (80-126 mg/dL) on the last three mornings of each weekly dosing interval. Frequent blood sampling to assess total serum icodec concentration (ie, albumin-bound and unbound) occurred from first icodec dose until 35 days after last dose. Icodec trough concentrations following initiation of once-weekly dosing were predicted by pharmacokinetic modelling. During the final 3 weeks of icodec treatment, while at steady state, the icodec glucose-lowering effect was assessed in three glucose clamps (target 7.5 mmol/L [135 mg/dL]): 0 to 36, 40 to 64 and 144 to 168 h post-dose, thus covering the initial, middle and last part of the 1-week dosing interval. Glucose-lowering effect during a complete dosing interval was predicted by pharmacokinetic-pharmacodynamic modelling. RESULTS: Model-predicted icodec steady state was attained after 3 to 4 weeks. At steady state, model-predicted daily proportions of glucose-lowering effect on days 1 to 7 of the 1-week dosing interval were 14.1%, 16.1%, 15.8%, 15.0%, 14.0%, 13.0% and 12.0%, respectively. Icodec duration of action was at least 1 week in all participants. Once-weekly icodec was overall safe and well tolerated in the current trial. CONCLUSIONS: The pharmacokinetic and pharmacodynamic characteristics of icodec in individuals with T2D support its potential as a once-weekly basal insulin.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Glicemia , Método Duplo-Cego , Hipoglicemiantes , Insulina de Ação Prolongada , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
3.
Angew Chem Int Ed Engl ; 62(14): e202218094, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36744674

RESUMO

Metal coordination compound (MCC) glasses [e.g., metal-organic framework (MOF) glass, coordination polymer glass, and metal inorganic-organic complex (MIOC) glass] are emerging members of the hybrid glass family. So far, a limited number of crystalline MCCs can be converted into glasses by melt-quenching. Here, we report a universal wet-chemistry method, by which the super-sized supramolecular MIOC glasses can be synthesized from non-meltable MOFs. Alcohol and acid were used as agents to inhibit crystallization. The MIOC glasses demonstrate unique features including high transparency, shaping capability, and anisotropic network. Directional photoluminescence with a large polarization ratio (≈47 %) was observed from samples doped with organic dyes. This crystallization-suppressing approach enables fabrication of super-sized MCC glasses, which cannot be achieved by conventional vitrification methods, and thus allows for exploring new MCC glasses possessing photonic functionalities.

4.
Endocr Res ; 45(1): 58-71, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31566019

RESUMO

Background: Being born with low birth weight (LBW) is a risk factor for muscle insulin resistance and type 2 diabetes (T2D), which may be mediated by epigenetic mechanisms programmed by the intrauterine environment. Epigenetic mechanisms exert their prime effects in developing cells. We hypothesized that muscle insulin resistance in LBW subjects may be due to early differential epigenomic and transcriptomic alterations in their immature muscle progenitor cells.Results: Muscle progenitor cells were obtained from 23 healthy young adult men born at term with LBW, and 15 BMI-matched normal birth weight (NBW) controls. The cells were subsequently cultured and differentiated into myotubes. DNA and RNA were harvested before and after differentiation for genome-wide DNA methylation and RNA expression measurements.After correcting for multiple comparisons (q ≤ 0.05), 56 CpG sites were found to be significantly, differentially methylated in myoblasts from LBW compared with NBW men, of which the top five gene-annotated CpG sites (SKI, ARMCX3, NR5A2, NEUROG, ESRRG) previously have been associated to regulation of cholesterol, fatty acid and glucose metabolism and muscle development or hypertrophy. LBW men displayed markedly decreased myotube gene expression levels of the AMPK-repressing tyrosine kinase gene FYN and the histone deacetylase gene HDAC7. Silencing of FYN and HDAC7 was associated with impaired myotube formation, which for HDAC7 reduced muscle glucose uptake.Conclusions: The data provides evidence of impaired muscle development predisposing LBW individuals to T2D is linked to and potentially caused by distinct DNA methylation and transcriptional changes including down regulation of HDAC7 and FYN in their immature myoblast stem cells.


Assuntos
Regulação para Baixo/genética , Epigenoma/genética , Recém-Nascido de Baixo Peso , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , Transcriptoma/genética , Adulto , Humanos , Masculino , Adulto Jovem
5.
Eur J Anaesthesiol ; 37(6): 491-502, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31972601

RESUMO

BACKGROUND: Goal-directed therapy (GDT) is increasingly used in abdominal surgery. Whether crystalloids can exert the same effect as colloid, and how this may affect perfusion, is still unclear. The effect of GDT on the systemic oxygen delivery index (sDO2I) and the mesenteric oxygen delivery index (mDO2I) can be quantified by measuring cardiac index and flow in the superior mesenteric artery, respectively. OBJECTIVE: The aim of this study was to test the hypothesis that intra-operative GDT with bolus human albumin 5% is superior to GDT with bolus ringer acetate in maintaining sDO2I and mDO2I in elective major upper gastrointestinal cancer surgery. DESIGN: Randomised controlled double blinded trial. SETTING: Odense University Hospital, Denmark, from May 2014 to June 2015. PATIENTS: A total of 89 adults scheduled for elective major upper gastrointestinal cancer surgery were randomised and data from 60 were analysed. EXCLUSION CRITERIA: contraindications for using the LiDCOplus system, known allergy to albumin, pre-operative renal failure, pancreatic cancer and pre-operative down staging using chemotherapy and/or radiation therapy, pregnancy. INTERVENTIONS: Patients were randomised to intra-operative GDT with either bolus human albumin or ringer acetate 250 ml, guided by pulse pressure variation and stroke volume. MAIN OUTCOME MEASURES: Changes in sDO2I and mDO2I. Secondary outcomes were changes in other haemodynamic variables, fluid balance, blood transfusions, fluid-related complications and length of stay (LOS) in ICU and hospital. RESULTS: Median [IQR] sDO2I was 522 [420 to 665] ml min m in the ringer acetate group and 490 [363 to 676] ml min m in the human albumin group, P = 0.36. Median [IQR] mDO2I was 12.1 [5.8 to 28.7] ml min m in the ringer acetate group and 17.0 [7.6 to 27.5] ml min m in the human albumin group, P = 0.17. Other haemodynamic comparisons did not differ significantly. More trial fluid was administered in the ringer acetate group. We found no significant difference in transfusions, complications or LOS. CONCLUSION: Bolus human albumin 5% was not superior to bolus ringer acetate in maintaining systemic or mesenteric oxygen delivery in elective major upper gastrointestinal cancer surgery, despite the administration of larger volumes of trial fluid in the ringer acetate group. No significant difference was seen in fluid-related complications or LOS. TRIAL REGISTRATION: https://eudract.ema.europa.eu/ Identifier: 2013-002217-36.


Assuntos
Abdome/cirurgia , Acetatos , Albuminas , Terapia Precoce Guiada por Metas , Complicações Pós-Operatórias , Adulto , Hidratação , Humanos , Oxigênio
6.
Physiol Genomics ; 51(6): 254-260, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074700

RESUMO

The Ala allele of PPARG Pro12Ala ( rs1801282 ) is associated with greater improvements to the glucose metabolism in exercise studies, but whether this extends to peripheral insulin sensitivity is unknown. Our objective was to investigate the effect of PPARG Pro12Ala on exercise-induced changes in peripheral insulin sensitivity. A total of 124 (91 Pro homozygotes and 33 Ala carriers) previously physically inactive healthy young men and women with overweight or class 1 obesity who completed a 12 wk aerobic exercise intervention were included in the analysis. All participants underwent a hyperinsulinemic euglycemic clamp before and after the 12 wk intervention. The prescribed exercise frequency was 5-7 days/wk, and the exercise energy expenditure was 2,100 4,200 kcal/wk for men and 1,600 kcal/wk for women. Insulin sensitivity improved significantly in both genotype groups. However, Ala carriers had a 1.13-fold (95% confidence interval 1.01; 1.26, P = 0.032) greater improvement in insulin sensitivity from baseline compared with Pro homozygotes. Our data support that PPARG Pro12Ala modifies the effect of aerobic exercise on peripheral insulin sensitivity.


Assuntos
Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , PPAR gama/metabolismo , Adulto , Alelos , Índice de Massa Corporal , Metabolismo Energético/fisiologia , Feminino , Genótipo , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Adulto Jovem
7.
Endocr Res ; 44(3): 110-116, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30721637

RESUMO

Aim: The TCF7L2 gene variant rs7903146 has the largest effect on type 2 diabetes risk reported in genome-wide association studies, however its role in adipose tissue development and function is unknown. We investigate the association between gene variant rs7903146 and metabolic parameters and examine in vitro and ex vivo gene expression of TCF7L2 in human adipose tissue and progenitor cells from two independent populations of young healthy men with increased risk of type 2 diabetes due to low birth weight (LBW). Design: Adipose tissue biopsies were excised from 40 healthy young men with low and normal birth weights (NBW) after a control and 5-day high-fat overfeeding diet. In another cohort including 13 LBW and 13 NBW men, adipocyte progenitor cells were isolated and cultivated. Transcriptome-wide expression was performed on RNA extracted from biopsies or cell cultures. Results: Diet-induced peripheral insulin resistance is more pronounced in carriers of the T-risk allele rs7903146, whereas no association with hepatic insulin resistance was shown. TCF7L2 expression increased during adipogenesis in isolated preadipocytes from both LBW and NBW men (p < 0.001) and correlated positively with markers of progenitor cell proliferation and maturation capacity. In the mature adipose tissue, LBW men had lower expression of TCF7L2 compared to NBW men at baseline (p = 0.03) and TCF7L2 expression was suppressed by short-term overfeeding in NBW men (p = 0.005). Conclusions: The results suggest a regulation of TCF7L2 expression during adipogenesis and in mature adipose tissue upon overfeeding, and further that young men exposed to an adverse intrauterine environment have reduced mature adipose tissue TCF7L2 expression.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo/metabolismo , Diferenciação Celular/fisiologia , Dieta Hiperlipídica , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Adulto , Alelos , Estudos Cross-Over , Diabetes Mellitus Tipo 2/genética , Humanos , Recém-Nascido de Baixo Peso , Resistência à Insulina/fisiologia , Masculino , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Adulto Jovem
8.
Diabetologia ; 59(12): 2664-2673, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27627980

RESUMO

AIMS/HYPOTHESIS: Low birthweight (LBW) is associated with dysfunctions of adipose tissue and metabolic disease in adult life. We hypothesised that altered epigenetic and transcriptional regulation of adipose-derived stem cells (ADSCs) could play a role in programming adipose tissue dysfunction in LBW individuals. METHODS: ADSCs were isolated from the subcutaneous adipose tissue of 13 normal birthweight (NBW) and 13 LBW adult men. The adipocytes were cultured in vitro, and genome-wide differences in RNA expression and DNA methylation profiles were analysed in ADSCs and differentiated adipocytes. RESULTS: We demonstrated that ADSCs from LBW individuals exhibit multiple expression changes as well as genome-wide alterations in methylation pattern. Reduced expression of the transcription factor cyclin T2 encoded by CCNT2 may play a key role in orchestrating several of the gene expression changes in ADSCs from LBW individuals. Indeed, silencing of CCNT2 in human adipocytes decreased leptin secretion as well as the mRNA expression of several genes involved in adipogenesis, including MGLL, LIPE, PPARG, LEP and ADIPOQ. Only subtle genome-wide mRNA expression and DNA methylation changes were seen in mature cultured adipocytes from LBW individuals. CONCLUSIONS/INTERPRETATION: Epigenetic and transcriptional changes in LBW individuals are most pronounced in immature ADSCs that in turn may programme physiological characteristics of the mature adipocytes that influence the risk of metabolic diseases. Reduced expression of CCNT2 may play a key role in the developmental programming of adipose tissue.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Adipogenia/genética , Adiponectina/genética , Adulto , Peso ao Nascer/genética , Peso ao Nascer/fisiologia , Células Cultivadas , Ciclina T/genética , Humanos , Masculino , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT2/genética , Adulto Jovem
9.
Diabetologia ; 58(5): 1006-12, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25660259

RESUMO

AIMS/HYPOTHESIS: We examined the extent to which surrogate measures of insulin release have shared genetic causes. METHODS: Genetic and phenotypic correlations were calculated in a family cohort (n = 315) in which beta cell indices were estimated based on fasting and oral glucose-stimulated plasma glucose, serum C-peptide and serum insulin levels. Furthermore, we genotyped a large population-based cohort (n = 6,269) for common genetic variants known to associate with type 2 diabetes, fasting plasma glucose levels or fasting serum insulin levels to examine their association with various indices. RESULTS: We found a notable difference between the phenotypic and genetic correlations for the traits, emphasising that the phenotypic correlation is an insufficient measure of the magnitude of shared genetic impact. In addition, we found that corrected insulin response, insulinogenic index and incAUC for insulin after an oral glucose challenge shared the majority of their genetic backgrounds, with genetic correlations of 0.80-0.99. The BIGTT index for acute insulin response differed slightly more from the latter with genetic correlations of 0.78-0.87. The HOMA for beta cell function was genetically closely related to fasting insulin with a genetic correlation of 0.85. The effects of 82 selected susceptibility single nucleotide polymorphisms on these insulin secretion indices supported our interpretation of the data and added insight into the biological differences between the examined traits. CONCLUSIONS/INTERPRETATION: The level of shared genetic background varies between surrogate measures of insulin release, and this should be considered when designing a genetic association study to best obtain information on various mechanisms of insulin release.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Resistência à Insulina/genética , Insulina/sangue , Adulto , Peptídeo C/sangue , Diabetes Mellitus Tipo 2/sangue , Jejum , Feminino , Genótipo , Teste de Tolerância a Glucose , Humanos , Células Secretoras de Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
10.
Diabetologia ; 57(6): 1154-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24570141

RESUMO

AIMS/HYPOTHESIS: The association between low birthweight (LBW) and risk of developing type 2 diabetes may involve epigenetic mechanisms, with skeletal muscle being a prime target tissue. Differential DNA methylation patterns have been observed in single genes in muscle tissue from type 2 diabetic and LBW individuals, and we recently showed multiple DNA methylation changes during short-term high-fat overfeeding in muscle of healthy people. In a randomised crossover study, we analysed genome-wide DNA promoter methylation in skeletal muscle of 17 young LBW men and 23 matched normal birthweight (NBW) men after a control and a 5 day high-fat overfeeding diet. METHODS: DNA methylation was measured using Illumina's Infinium BeadArray covering 27,578 CpG sites representing 14,475 different genes. RESULTS: After correction for multiple comparisons, DNA methylation levels were found to be similar in the LBW and NBW groups during the control diet. Whereas widespread DNA methylation changes were observed in the NBW group in response to high-fat overfeeding, only a few methylation changes were seen in the LBW group (χ(2), p < 0.001). CONCLUSIONS/INTERPRETATION: Our results indicate lower DNA methylation plasticity in skeletal muscle from LBW vs NBW men, potentially contributing to understanding the link between LBW and increased risk of type 2 diabetes.


Assuntos
Metilação de DNA/genética , Dieta Hiperlipídica/efeitos adversos , Recém-Nascido de Baixo Peso/fisiologia , Adulto , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Diabetes Mellitus Tipo 2/genética , Epigênese Genética/genética , Humanos , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Masculino , Músculo Esquelético/metabolismo , Adulto Jovem , DNA Metiltransferase 3B
11.
Acta Obstet Gynecol Scand ; 93(11): 1099-108, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25179736

RESUMO

Low birthweight (LBW) individuals and offspring of women with gestational diabetes mellitus (GDM) exhibit increased risk of developing type 2 diabetes (T2D) and associated cardiometabolic traits in adulthood, which for both groups may be mediated by adverse events and developmental changes in fetal life. T2D is a multifactorial disease occurring as a result of complicated interplay between genetic and both prenatal and postnatal nongenetic factors, and it remains unknown to what extent the increased risk of T2D associated with LBW or GDM in the mother may be due to, or confounded by, genetic factors. Indeed, it has been shown that genetic changes influencing risk of diabetes may also be associated with reduced fetal growth as a result of reduced insulin secretion and/or action. Similarly, increased risk of T2D among offspring could be explained by T2D susceptibility genes shared between the mother and her offspring. Epigenetic mechanisms may explain the link between factors operating in fetal life and later risk of developing T2D, but so far convincing evidence is lacking for epigenetic changes as a prime and direct cause of T2D. This review addresses recent literature on the early origins of adult disease hypothesis, with a special emphasis on the role of genetic compared with nongenetic and epigenetic risk determinants and disease mechanisms.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Gestacional/fisiopatologia , Epigênese Genética/genética , Epigênese Genética/fisiologia , Desenvolvimento Fetal/genética , Desenvolvimento Fetal/fisiologia , Predisposição Genética para Doença/genética , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Feminino , Predisposição Genética para Doença/epidemiologia , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Fatores de Risco
12.
Sci Rep ; 14(1): 5538, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448554

RESUMO

Globally, food production for an ever-growing population is a well-known threat to the environment due to losses of excess reactive nitrogen (N) from agriculture. Since the 1980s, many countries of the Global North, such as Denmark, have successfully combatted N pollution in the aquatic environment by regulation and introduction of national agricultural one-size-fits-all mitigation measures. Despite this success, further reduction of the N load is required to meet the EU water directives demands, and implementation of additional targeted N regulation of agriculture has scientifically and politically been found to be a way forward. In this paper, we present a comprehensive concept to make future targeted N regulation successful environmentally and economically. The concept focus is on how and where to establish detailed maps of the groundwater denitrification potential (N retention) in areas, such as Denmark, covered by Quaternary deposits. Quaternary deposits are abundant in many parts of the world, and often feature very complex geological and geochemical architectures. We show that this subsurface complexity results in large local differences in groundwater N retention. Prioritization of the most complex areas for implementation of the new concept can be a cost-efficient way to achieve lower N impact on the aquatic environment.

13.
Am J Physiol Endocrinol Metab ; 304(6): E631-9, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23321478

RESUMO

Type 2 diabetes is characterized by reduced muscle glycogen synthesis. The key enzyme in this process, glycogen synthase (GS), is activated via proximal insulin signaling, but the exact molecular events remain unknown. Previously, we demonstrated that phosphorylation of Thr³°8 on Akt (p-Akt-Thr³°8), Akt2 activity, and GS activity in muscle were positively associated with insulin sensitivity. Here, in the same study population, we determined the influence of several upstream elements in the canonical PI3K signaling on muscle GS activation. One-hundred eighty-one nondiabetic twins were examined with the euglycemic hyperinsulinemic clamp combined with excision of muscle biopsies. Insulin signaling was evaluated at the levels of the insulin receptor, IRS-1-associated PI3K (IRS-1-PI3K), Akt, and GS employing activity assays and phosphospecific Western blotting. The insulin-stimulated GS activity was positively associated with p-Akt-Thr³°8 (P = 0.01) and Akt2 activity (P = 0.04) but not p-Akt-Ser47³ or IRS-1-PI3K activity. Furthermore, p-Akt-Thr³°8 and Akt2 activity were negatively associated with NH2-terminal GS phosphorylation (P = 0.001 for both), which in turn was negatively associated with insulin-stimulated GS activity (P < 0.001). We found no association between COOH-terminal GS phosphorylation and Akt or GS activity. Employing whole body Akt2-knockout mice, we validated the necessity for Akt2 in insulin-mediated GS activation. However, since insulin did not affect NH2-terminal phosphorylation in mice, we could not use this model to validate the observed association between GS NH2-terminal phosphorylation and Akt activity in humans. In conclusion, our study suggests that although COOH-terminal dephosphorylation is likely necessary for GS activation, Akt2-dependent NH2-terminal dephosphorylation may be the site for "fine-tuning" insulin-mediated GS activation in humans.


Assuntos
Glicogênio Sintase/metabolismo , Insulina/metabolismo , Músculo Esquelético/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Adulto , Idoso , Animais , Estudos de Coortes , Estudos Transversais , Ativação Enzimática , Feminino , Humanos , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Músculo Esquelético/enzimologia , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/genética , Treonina/metabolismo , Adulto Jovem
14.
Aging Cell ; 22(3): e13763, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36617632

RESUMO

Intronic single-nucleotide polymorphisms (SNPs) in FOXO3A are associated with human longevity. Currently, it is unclear how these SNPs alter FOXO3A functionality and human physiology, thereby influencing lifespan. Here, we identify a primate-specific FOXO3A transcriptional isoform, FOXO3A-Short (FOXO3A-S), encoding a major longevity-associated SNP, rs9400239 (C or T), within its 5' untranslated region. The FOXO3A-S mRNA is highly expressed in the skeletal muscle and has very limited expression in other tissues. We find that the rs9400239 variant influences the stability and functionality of the primarily nuclear protein(s) encoded by the FOXO3A-S mRNA. Assessment of the relationship between the FOXO3A-S polymorphism and peripheral glucose clearance during insulin infusion (Rd clamp) in a cohort of Danish twins revealed that longevity T-allele carriers have markedly faster peripheral glucose clearance rates than normal lifespan C-allele carriers. In vitro experiments in human myotube cultures utilizing overexpression of each allele showed that the C-allele represses glycolysis independently of PI3K signaling, while overexpression of the T-allele represses glycolysis only in a PI3K-inactive background. Supporting this finding inducible knockdown of the FOXO3A-S C-allele in cultured myotubes increases the glycolytic rate. We conclude that the rs9400239 polymorphism acts as a molecular switch which changes the identity of the FOXO3A-S-derived protein(s), which in turn alters the relationship between FOXO3A-S and insulin/PI3K signaling and glycolytic flux in the skeletal muscle. This critical difference endows carriers of the FOXO3A-S T-allele with consistently higher insulin-stimulated peripheral glucose clearance rates, which may contribute to their longer and healthier lifespans.


Assuntos
Glucose , Longevidade , Animais , Humanos , Proteína Forkhead Box O3/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Insulina/genética , Insulina/metabolismo , Longevidade/genética , Fosfatidilinositol 3-Quinases/genética , RNA Mensageiro
15.
J Proteome Res ; 11(7): 3796-804, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22574709

RESUMO

Assessment of disease activity in patients with rheumatoid arthritis (RA) is of importance in the evaluation of treatment. The most important measure of disease activity is the Disease Activity Score counted in 28 joints (DAS28). In this study, we evaluated whether metabolic profiling could complement current measures of disease activity. Fifty-six patients, in two separate studies, were followed for two years after commencing anti-TNF therapy. DAS28 was assessed, and metabolic profiles were recorded at defined time points. Correlations between metabolic profile and DAS28 scores were analyzed using multivariate statistics. The metabolic responses to lowering DAS28 scores varied in different patients but could predict DAS28 scores at the individual and subgroup level models. The erythrocyte sedimentation rate (ESR) component in DAS28 was most correlated to the metabolite data, pointing to inflammation as the primary effect driving metabolic profile changes. Patients with RA had differing metabolic response to changes in DAS28 following anti-TNF therapy. This suggests that discovery of new metabolic biomarkers for disease activity will derive from studies at the individual and subgroup level. Increased inflammation, measured as ESR, was the main common effect seen in metabolic profiles from periods associated with high DAS28.


Assuntos
Artrite Reumatoide/sangue , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Biomarcadores/sangue , Sedimentação Sanguínea , Feminino , Humanos , Infliximab , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Índice de Gravidade de Doença
16.
Anal Chem ; 84(15): 6869-76, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22823568

RESUMO

A strategy for optimizing LC-MS metabolomics data processing is proposed. We applied this strategy on the XCMS open source package written in R on both human and plant biology data. The strategy is a sequential design of experiments (DoE) based on a dilution series from a pooled sample and a measure of correlation between diluted concentrations and integrated peak areas. The reliability index metric, used to define peak quality, simultaneously favors reliable peaks and disfavors unreliable peaks using a weighted ratio between peaks with high and low response linearity. DoE optimization resulted in the case studies in more than 57% improvement in the reliability index compared to the use of the default settings. The proposed strategy can be applied to any other data processing software involving parameters to be tuned, e.g., MZmine 2. It can also be fully automated and used as a module in a complete metabolomics data processing pipeline.


Assuntos
Cromatografia Líquida , Espectrometria de Massas , Metabolômica , Projetos de Pesquisa , Adulto , Humanos , Masculino , Plantas/metabolismo , Urinálise
17.
Chem Commun (Camb) ; 58(6): 823-826, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34929725

RESUMO

The effect of substituting linkers with electron-donating moieties for part of the conventional ones on the melting and glass transition behaviours of ZIF-62 was investigated by calorimetry and X-ray diffraction. Specifically, substituting 5,6-dimethylbenzimidazole for benzimidazole in ZIF-62 increases both Tm and Tg. The structural origin of this effect was explained.

18.
RSC Adv ; 12(17): 10815-10824, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35424998

RESUMO

We synthesized two series of bimetallic (zinc and cobalt) zeolitic imidazolate frameworks (ZIF-62) under different solvothermal conditions. It is found that the structure of the derived ZIF crystals is highly sensitive to synthesis conditions. One series possesses the standard ZIF-62 structure, whereas the other has a mixed structure composed of both the standard structure and an unknown one. The standard series exhibits a slight negative deviation from linearity of melting temperature (T m) and glass transition temperature (T g) with the substitution of Co for Zn. In contrast, the new series displays a stronger negative deviation. These negative deviations from linearity indicate the mixed metal node effect in bimetallic ZIF-62 due to the structural mismatch between Co2+ and Zn2+ and to the difference in their electronic configurations. The new series involves both cobalt-rich and zinc-rich phases, whereas the standard one shows one homogeneous phase. Density functional theory calculations predict that the substitution of Co for Zn increases the bulk modulus of the ZIF crystals. This work indicates that the structure, melting behaviour, and mechanical properties of ZIFs can be tuned by metal node substitution and by varying the synthetic conditions. Both series of ZIFs have higher glass forming abilities due to their higher T g/T m ratios (0.77-0.84) compared to most good glass formers.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34413118

RESUMO

INTRODUCTION: Insulin icodec is a novel, long-acting insulin analog designed to cover basal insulin requirements with once-weekly subcutaneous administration. Here we describe the molecular engineering and the biological and pharmacological properties of insulin icodec. RESEARCH DESIGN AND METHODS: A number of in vitro assays measuring receptor binding, intracellular signaling as well as cellular metabolic and mitogenic responses were used to characterize the biological properties of insulin icodec. To evaluate the pharmacological properties of insulin icodec in individuals with type 2 diabetes, a randomized, double-blind, double-dummy, active-controlled, multiple-dose, dose escalation trial was conducted. RESULTS: The long half-life of insulin icodec was achieved by introducing modifications to the insulin molecule aiming to obtain a safe, albumin-bound circulating depot of insulin icodec, providing protracted insulin action and clearance. Addition of a C20 fatty diacid-containing side chain imparts strong, reversible albumin binding, while three amino acid substitutions (A14E, B16H and B25H) provide molecular stability and contribute to attenuating insulin receptor (IR) binding and clearance, further prolonging the half-life. In vitro cell-based studies showed that insulin icodec activates the same dose-dependent IR-mediated signaling and metabolic responses as native human insulin (HI). The affinity of insulin icodec for the insulin-like growth factor-1 receptor was proportionately lower than its binding to the IR, and the in vitro mitogenic effect of insulin icodec in various human cells was low relative to HI. The clinical pharmacology trial in people with type 2 diabetes showed that insulin icodec was well tolerated and has pharmacokinetic/pharmacodynamic properties that are suited for once-weekly dosing, with a mean half-life of 196 hours and close to even distribution of glucose-lowering effect over the entire dosing interval of 1 week. CONCLUSIONS: The molecular modifications introduced into insulin icodec provide a novel basal insulin with biological and pharmacokinetic/pharmacodynamic properties suitable for once-weekly dosing. TRIAL REGISTRATION NUMBER: NCT02964104.


Assuntos
Diabetes Mellitus Tipo 2 , Insulina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/farmacologia , Insulina de Ação Prolongada , Insulina Regular Humana
20.
Science ; 367(6485): 1473-1476, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32217725

RESUMO

The structure of melt-quenched zeolitic imidazole framework (ZIF) glasses can provide insights into their glass-formation mechanism. We directly detected short-range disorder in ZIF glasses using ultrahigh-field zinc-67 solid-state nuclear magnetic resonance spectroscopy. Two distinct Zn sites characteristic of the parent crystals transformed upon melting into a single tetrahedral site with a broad distribution of structural parameters. Moreover, the ligand chemistry in ZIFs appeared to have no controlling effect on the short-range disorder, although the former affected their phase-transition behavior. These findings reveal structure-property relations and could help design metal-organic framework glasses.

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