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1.
J Physiol ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38050414

RESUMO

It is unclear how skeletal muscle metabolism and mitochondrial function adapt to long duration bed rest and whether changes can be prevented by nutritional intervention. The present study aimed (1) to assess the effect of prolonged bed rest on skeletal muscle mitochondrial function and dynamics and (2) to determine whether micronutrient supplementation would mitigate the adverse metabolic effect of bed rest. Participants were maintained in energy balance throughout 60 days of bed rest with micronutrient supplementation (INT) (body mass index: 23.747 ± 1.877 kg m-2 ; 34.80 ± 7.451 years; n = 10) or without (control) (body mass index: 24.087 ± 2.088 kg m-2 ; 33.50 ± 8.541 years; n = 10). Indirect calorimetry and dual-energy x-ray absorptiometry were used for measures of energy expenditure, exercise capacity and body composition. Mitochondrial respiration was determined by high-resolution respirometry in permeabilized muscle fibre bundles from vastus lateralis biopsies. Protein and mRNA analysis further examined the metabolic changes relating to regulators of mitochondrial dynamics induced by bed rest. INT was not sufficient in preserving whole body metabolic changes conducive of a decrease in body mass, fat-free mass and exercise capacity within both groups. Mitochondrial respiration, OPA1 and Drp1 protein expression decreased with bed rest, with an increase pDrp1s616 . This reduction in mitochondrial respiration was explained through an observed decrease in mitochondrial content (mtDNA:nDNA). Changes in regulators of mitochondrial dynamics indicate an increase in mitochondrial fission driven by a decrease in inner mitochondrial membrane fusion (OPA1) and increased pDrp1s616 . KEY POINTS: Sixty days of -6° head down tilt bed rest leads to significant changes in body composition, exercise capacity and whole-body substrate metabolism. Micronutrient supplementation throughout bed rest did not preserve whole body metabolic changes. Bed rest results in a decrease in skeletal muscle mitochondrial respiratory capacity, mainly as a result of an observed decrease in mitochondrial content. Prolonged bed rest ensues changes in key regulators of mitochondrial dynamics. OPA1 and Drp1 are significantly reduced, with an increase in pDrp1s616 following bed rest indicative of an increase in mitochondrial fission. Given the reduction in mitochondrial content following 60 days of bed rest, the maintenance of regulators of mitophagy in line with the increase in regulators of mitochondrial fission may act to maintain mitochondrial respiration to meet energy demands.

2.
Diabetes Obes Metab ; 25(3): 805-814, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36433713

RESUMO

AIMS: This study investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of danuglipron (PF-06882961), which is a novel, oral small-molecule glucagon-like peptide-1 receptor agonist, in Japanese participants with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: This phase 1, randomized, double-blind, placebo-controlled, parallel-group study enrolled adult Japanese participants with T2DM inadequately controlled on diet and exercise. Participants received twice-daily oral doses of placebo or multiple ascending doses of danuglipron titrated to 40, 80 or 120 mg twice daily over 8 weeks. The primary outcome was the safety and tolerability of danuglipron. Secondary and exploratory outcomes included plasma pharmacokinetics, glycaemic parameters and body weight. RESULTS: In the 37 participants randomized, the most common treatment-emergent adverse events were nausea, vomiting, abdominal discomfort, diarrhoea and headache. Most treatment-emergent adverse events were of mild or moderate intensity. Dose-proportional increases in danuglipron exposure parameters were observed at steady state (Day 56). Significant reductions from baseline were observed with danuglipron on Day 56 for mean daily glucose [least squares mean (90% confidence interval) placebo-adjusted difference of up to -67.89 (-88.98, -46.79) mg/dl] and on Day 57 for fasting plasma glucose [up to -40.87 (-53.77, -27.98) mg/dl], glycated haemoglobin [up to -1.41% (-2.01%, -0.82%)] and body weight [up to -1.87 (-3.58, -0.17) kg]. CONCLUSIONS: In Japanese adults with T2DM, danuglipron exhibited dose-proportional increases in plasma exposure at steady state and robustly reduced glycaemic parameters and body weight after 8 weeks of dosing, with a safety profile consistent with the mechanism of action.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hipoglicemiantes , Adulto , Humanos , Glicemia/análise , Peso Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Método Duplo-Cego , População do Leste Asiático , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico
3.
Diabetes Obes Metab ; 25(10): 2805-2814, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37311722

RESUMO

AIM: To evaluate the tolerability, safety and pharmacodynamics of different dose-escalation schemes of the oral small-molecule glucagon-like peptide-1 receptor (GLP-1R) agonist danuglipron. MATERIALS AND METHODS: This Phase 2a, double-blind, placebo-controlled, parallel-group study randomly assigned adults with type 2 diabetes (T2D) treated with metformin to placebo or danuglipron (low [5-mg] or high [10-mg] starting dose, with 1- or 2-week dose-escalation steps, to target doses of 80, 120 or 200 mg twice daily [BID]) and adults with obesity without diabetes to placebo or danuglipron 200 mg BID. RESULTS: Participants with T2D (n = 123, mean glycated haemoglobin [HbA1c] 8.19%) or obesity without diabetes (n = 28, mean body mass index 37.3 kg/m2 ) were randomly assigned and treated. Discontinuation from study medication occurred in 27.3% to 72.7% of participants across danuglipron groups versus 16.7% to 18.8% for placebo, most often due to adverse events. Nausea (20.0%-47.6% of participants across danuglipron groups vs. 12.5% for placebo) and vomiting (18.2%-40.9% danuglipron vs. 12.5% placebo, respectively) were most commonly reported in participants with T2D. Gastrointestinal adverse events were generally related to danuglipron target dose and were not substantially affected by starting dose. In participants with T2D, least squares mean changes from baseline in HbA1c (-1.04% to -1.57% across danuglipron groups vs. -0.32% for placebo), fasting plasma glucose (-23.34 mg/dL to -53.94 mg/dL danuglipron vs. -13.09 mg/dL placebo) and body weight (-1.93 to -5.38 kg danuglipron vs. -0.42 kg placebo) at Week 12 were generally statistically significant for danuglipron compared with placebo (P < 0.05). CONCLUSIONS: Danuglipron resulted in statistically significant reductions in HbA1c, FPG and body weight over 12 weeks, in the setting of higher discontinuation rates and incidence of gastrointestinal adverse events with higher target doses. CLINICALTRIALS: gov identifier: NCT04617275.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Humanos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hemoglobinas Glicadas , Hipoglicemiantes/efeitos adversos , Peso Corporal , Obesidade/tratamento farmacológico , Obesidade/induzido quimicamente , Método Duplo-Cego , Resultado do Tratamento , Glicemia
4.
Eur J Nutr ; 61(7): 3649-3667, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35641800

RESUMO

PURPOSE: In several studies, exploratory dietary patterns (DP), derived by principal component analysis, were inversely or positively associated with incident type 2 diabetes (T2D). However, findings remained study-specific, inconsistent and rarely replicated. This study aimed to investigate the associations between DPs and T2D in multiple cohorts across the world. METHODS: This federated meta-analysis of individual participant data was based on 25 prospective cohort studies from 5 continents including a total of 390,664 participants with a follow-up for T2D (3.8-25.0 years). After data harmonization across cohorts we evaluated 15 previously identified T2D-related DPs for association with incident T2D estimating pooled incidence rate ratios (IRR) and confidence intervals (CI) by Piecewise Poisson regression and random-effects meta-analysis. RESULTS: 29,386 participants developed T2D during follow-up. Five DPs, characterized by higher intake of red meat, processed meat, French fries and refined grains, were associated with higher incidence of T2D. The strongest association was observed for a DP comprising these food groups besides others (IRRpooled per 1 SD = 1.104, 95% CI 1.059-1.151). Although heterogeneity was present (I2 = 85%), IRR exceeded 1 in 18 of the 20 meta-analyzed studies. Original DPs associated with lower T2D risk were not confirmed. Instead, a healthy DP (HDP1) was associated with higher T2D risk (IRRpooled per 1 SD = 1.057, 95% CI 1.027-1.088). CONCLUSION: Our findings from various cohorts revealed positive associations for several DPs, characterized by higher intake of red meat, processed meat, French fries and refined grains, adding to the evidence-base that links DPs to higher T2D risk. However, no inverse DP-T2D associations were confirmed.


Assuntos
Diabetes Mellitus Tipo 2 , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Dieta , Humanos , Incidência , Estudos Prospectivos , Fatores de Risco
5.
Int J Mol Sci ; 24(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36613662

RESUMO

Mannan-rich fraction (MRF) isolated from Saccharomyces cerevisiae has been studied for its beneficial impact on animal intestinal health. Herein, we examined how MRF affected the formation of reactive oxygen species (ROS), impacting antibiotic susceptibility in resistant Escherichia coli through the modulation of bacterial metabolism. The role of MRF in effecting proteomic change was examined using a proteomics-based approach. The results showed that MRF, when combined with bactericidal antibiotic treatment, increased ROS production in resistant E. coli by 59.29 ± 4.03% compared to the control (p ≤ 0.05). We further examined the effect of MRF alone and in combination with antibiotic treatment on E. coli growth and explored how MRF potentiates bacterial susceptibility to antibiotics via proteomic changes in key metabolic pathways. Herein we demonstrated that MRF supplementation in the growth media of ampicillin-resistant E. coli had a significant impact on the normal translational control of the central metabolic pathways, including those involved in the glycolysis-TCA cycle (p ≤ 0.05).


Assuntos
Antibacterianos , Escherichia coli , Animais , Antibacterianos/uso terapêutico , Escherichia coli/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Mananas/metabolismo , Proteômica , Testes de Sensibilidade Microbiana
6.
J Nutr ; 151(5): 1231-1240, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33693815

RESUMO

BACKGROUND: The consumption of legumes is promoted as part of a healthy diet in many countries but associations of total and types of legume consumption with type 2 diabetes (T2D) are not well established. Analyses across diverse populations are lacking despite the availability of unpublished legume consumption data in prospective cohort studies. OBJECTIVE: To examine the prospective associations of total and types of legume intake with the risk of incident T2D. METHODS: Meta-analyses of associations between total legume, pulse, and soy consumption and T2D were conducted using a federated approach without physical data-pooling. Prospective cohorts were included if legume exposure and T2D outcome data were available and the cohort investigators agreed to participate. We estimated incidence rate ratios (IRRs) and CIs of associations using individual participant data including ≤42,473 incident cases among 807,785 adults without diabetes in 27 cohorts across the Americas, Eastern Mediterranean, Europe, and Western Pacific. Random-effects meta-analysis was used to combine effect estimates and estimate heterogeneity. RESULTS: Median total legume intake ranged from 0-140 g/d across cohorts. We observed a weak positive association between total legume consumption and T2D (IRR = 1.02, 95% CI: 1.01 to 1.04) per 20 g/d higher intake, with moderately high heterogeneity (I2 = 74%). Analysis by region showed no evidence of associations in the Americas, Eastern Mediterranean, and Western Pacific. The positive association in Europe (IRR = 1.05, 95% CI: 1.01 to 1.10, I2 = 82%) was mainly driven by studies from Germany, UK, and Sweden. No evidence of associations was observed for the consumption of pulses or soy. CONCLUSIONS: These findings suggest no evidence of an association of legume intakes with T2D in several world regions. The positive association observed in some European studies warrants further investigation relating to overall dietary contexts in which legumes are consumed, including accompanying foods which may be positively associated with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Dieta , Fabaceae , Saúde Global , Proteínas de Soja , Estudos de Coortes , Humanos , Incidência , Fatores de Risco
7.
J Proteome Res ; 19(8): 3438-3451, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32609523

RESUMO

Muscle atrophy is a deleterious consequence of physical inactivity and is associated with increased morbidity and mortality. The aim of this study was to decipher the mechanisms involved in disuse muscle atrophy in eight healthy men using a 21 day bed rest with a cross-over design (control, with resistive vibration exercise (RVE), or RVE combined with whey protein supplementation and an alkaline salt (NEX)). The main physiological findings show a significant reduction in whole-body fat-free mass (CON -4.1%, RVE -4.3%, NEX -2.7%, p < 0.05), maximal oxygen consumption (CON -20.5%, RVE -6.46%, NEX -7.9%, p < 0.05), and maximal voluntary contraction (CON -15%, RVE -12%, and NEX -9.5%, p < 0.05) and a reduction in mitochondrial enzyme activity (CON -30.7%, RVE -31.3%, NEX -17%, p < 0.05). The benefits of nutrition and exercise countermeasure were evident with an increase in leg lean mass (CON -1.7%, RVE +8.9%, NEX +15%, p < 0.05). Changes to the vastus lateralis muscle proteome were characterized using mass spectrometry-based label-free quantitative proteomics, the findings of which suggest alterations to cell metabolism, mitochondrial metabolism, protein synthesis, and degradation pathways during bed rest. The observed changes were partially mitigated during RVE, but there were no significant pathway changes during the NEX trial. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the dataset identifier PXD006882. In conclusion, resistive vibration exercise, when combined with whey/alkalizing salt supplementation, could be an effective strategy to prevent skeletal muscle protein changes, muscle atrophy, and insulin sensitivity during medium duration bed rest.


Assuntos
Repouso em Cama , Vibração , Repouso em Cama/efeitos adversos , Estudos Cross-Over , Suplementos Nutricionais , Humanos , Masculino , Músculo Esquelético , Proteoma , Soro do Leite , Proteínas do Soro do Leite
8.
Hum Mol Genet ; 26(7): 1391-1406, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28199695

RESUMO

Understanding the interaction between humans and mosquitoes is a critical area of study due to the phenomenal burdens on public health from mosquito-transmitted diseases. In this study, we conducted the first genome-wide association studies (GWAS) of self-reported mosquito bite reaction size (n = 84,724), itchiness caused by bites (n = 69,057), and perceived attractiveness to mosquitoes (n = 16,576). In total, 15 independent significant (P < 5×10-8) associations were identified. These loci were enriched for immunity-related genes that are involved in multiple cytokine signalling pathways. We also detected suggestive enrichment of these loci in enhancer regions that are active in stimulated T-cells, as well as within loci previously identified as controlling central memory T-cell levels. Egger regression analysis between the traits suggests that perception of itchiness and attractiveness to mosquitoes is driven, at least in part, by the genetic determinants of bite reaction size.Our findings illustrate the complex genetic and immunological landscapes underpinning human interactions with mosquitoes.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Mordeduras e Picadas de Insetos/genética , Prurido/genética , Animais , Culicidae/genética , Culicidae/patogenicidade , Genótipo , Humanos , Mordeduras e Picadas de Insetos/patologia , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Prurido/patologia , Autorrelato , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
Br J Anaesth ; 123(2): e194-e203, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30915991

RESUMO

BACKGROUND: This study investigated the analgesic effects of two doses (15 and 65 mg) of PF-06372865, a novel α2/α3/α5 gamma-aminobutyric acid A (GABAA) subunit selective partial positive allosteric modulator (PAM), compared with placebo and pregabalin (300 mg) as a positive control. METHODS: We performed a randomised placebo-controlled crossover study (NCT02238717) in 20 healthy subjects, using a battery of pain tasks (electrical, pressure, heat, cold and inflammatory pain, including a paradigm of conditioned pain modulation). Pharmacodynamic measurements were performed at baseline and up to 10 h after dose. RESULTS: A dose of 15 mg PF-06372865 increased pain tolerance thresholds (PTTs) for pressure pain at a ratio of 1.11 (90% confidence interval [CI]: 1.02, 1.22) compared with placebo. A dose of 65 mg PF-06372865 led to an increase in PTT for the cold pressor at a ratio of 1.17 (90% CI: 1.03, 1.32), and pressure pain task: 1.11 (90% CI: 1.01, 1.21). Pregabalin showed an increase in PTT for pressure pain at a ratio of 1.15 (95% CI: 1.06, 1.26) and cold pressor task: 1.31 (90% CI: 1.16, 1.48). CONCLUSION: We conclude that PF-06372865 has analgesic potential at doses that do not induce significant sedation or other intolerable adverse events limiting its clinical use. In addition, the present study established the potential role for this battery of pain tasks as a tool in the development of analgesics with a novel mechanism of action, for the treatment of various pain states including neuropathic pain and to establish proof-of-concept. CLINICAL TRIALS REGISTRATION: NCT0223871.


Assuntos
Analgésicos/farmacologia , Imidazóis/farmacologia , Dor/tratamento farmacológico , Piridazinas/farmacologia , Adulto , Analgésicos/uso terapêutico , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Imidazóis/uso terapêutico , Masculino , Piridazinas/uso terapêutico
10.
Br J Clin Pharmacol ; 84(2): 301-309, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29178434

RESUMO

AIM: Inhibitors of nerve growth factor (NGF) reduce pain in several chronic pain indications. NGF signals through tyrosine kinase receptors of the tropomyosin-related kinase (Trk) family and the unrelated p75 receptor. PF-06273340 is a small molecule inhibitor of Trks A, B and C that reduces pain in nonclinical models, and the present study aimed to investigate the pharmacodynamics of this first-in-class molecule in humans. METHODS: A randomized, double-blind, single-dose, placebo- and active-controlled five-period crossover study was conducted in healthy human subjects (NCT02260947). Subjects received five treatments: PF-06273340 50 mg, PF-06273340 400 mg, pregabalin 300 mg, ibuprofen 600 mg and placebo. The five primary endpoints were the pain detection threshold for the thermal pain tests and the pain tolerance threshold for the cold pressor, electrical stair and pressure pain tests. The trial had predefined decision rules based on 95% confidence that the PF-06273340 effect was better than that of placebo. RESULTS: Twenty subjects entered the study, with 18 completing all five periods. The high dose of PF-06273340 met the decision rules on the ultraviolet (UV) B skin thermal pain endpoint [least squares (LS) mean vs. placebo: 1.13, 95% confidence interval: 0.64-1.61], but not on the other four primary endpoints. The low dose did not meet the decision criteria for any of the five primary endpoints. Pregabalin (cold pressor and electrical stair tests) and ibuprofen (UVB thermal pain) showed significant analgesic effects on expected endpoints. CONCLUSIONS: The study demonstrated, for the first time, the translation of nonclinical effects into man in an inflammatory pain analgesic pharmacodynamic endpoint using a pan-Trk inhibitor.


Assuntos
Analgésicos/uso terapêutico , Hiperalgesia/tratamento farmacológico , Glicoproteínas de Membrana/antagonistas & inibidores , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Receptor trkA/antagonistas & inibidores , Receptor trkB/antagonistas & inibidores , Receptor trkC/antagonistas & inibidores , Adolescente , Adulto , Analgésicos/administração & dosagem , Analgésicos/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Hiperalgesia/enzimologia , Masculino , Pessoa de Meia-Idade , Limiar da Dor/efeitos dos fármacos , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Pirróis/administração & dosagem , Pirróis/farmacocinética , Adulto Jovem
11.
Endocr Pract ; 24(4): 342-350, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29658834

RESUMO

OBJECTIVE: Alterations in the thyroid axis are frequently observed following growth hormone (GH) replacement, but uncertainty exists regarding their clinical significance. We aimed to compare fluctuations in circulating thyroid hormone levels, induced by GH, to changes in sensitive biological markers of thyroid hormone action. METHODS: This was a prospective observational clinical study. Twenty hypopituitary men were studied before and after GH replacement. Serum thyroid-stimulating hormone (TSH), thyroid hormones, and insulin-like growth factor 1 were measured. Changes in thyroid hormone concentrations were compared to alterations in resting metabolic rate and cardiac time intervals. Health-related quality of life (QOL) was assessed by disease-sensitive and generic questionnaires. RESULTS: Following GH replacement, free thyroxine concentration declined and free triiodothyronine level increased. Resting energy expenditure increased, particularly in subjects with profound hypopituitarism, including TSH deficiency (16.73 ± 1.75 kcal/kg/min vs. 17.96 ± 2.26 kcal/kg/min; P = .01). Alterations in the thyroid axis were more pronounced in subjects with a low/normal baseline respiratory quotient (RQ) who experienced a paradoxical rise in RQ (0.81 vs. 0.86; P = .01). Subjects with a high baseline RQ experienced a slight but nonsignificant fall in RQ without alteration in thyroid axis. The isovolumetric contraction time was shortened during the study; however, this did not reach statistical significance. Improvements in QOL were observed despite alterations in thyroid axis. CONCLUSION: Changes in the thyroid axis following GH replacement are associated with complex tissue-specific effects. These fluctuations may induce a hypothyroid phenotype in some tissues while appearing to improve the biological action of thyroid hormone in other organs. ABBREVIATIONS: AGHDA = Assessment of Growth Hormone Deficiency in Adulthood; CHOox = carbohydrate oxidation; ET = ejection time; fT3 = free triiodothyronine; fT4 = free thyroxine; GH = growth hormone; GHD = growth hormone deficiency; HB-RQ = high baseline respiratory quotient; HPT = hypothalamic-pituitary-thyroid; ICT = isovolumetric contraction time; IGF-1 = insulin-like growth factor 1; IRT = isovolumetric relaxation time; LB-RQ = low baseline respiratory quotient; LV = left ventricular; NHP = Nottingham Health Profile; QOL = quality of life; REE = resting energy expenditure; RQ = respiratory quotient; rT3 = reverse triiodothyronine; SF-36 = Short Form 36; TSH = thyroid-stimulating hormone; T3 = triiodothyronine; T4 = thyroxine; TT3 = total triiodothyronine; TT4 = total thyroxine.


Assuntos
Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Hormônios Tireóideos/sangue , Adulto , Idoso , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Estudos Prospectivos , Qualidade de Vida , Hormônios Tireóideos/fisiologia
12.
J Proteome Res ; 16(7): 2623-2638, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28590761

RESUMO

The safety of space flight is challenged by a severe loss of skeletal muscle mass, strength, and endurance that may compromise the health and performance of astronauts. The molecular mechanisms underpinning muscle atrophy and decreased performance have been studied mostly after short duration flights and are still not fully elucidated. By deciphering the muscle proteome changes elicited in mice after a full month aboard the BION-M1 biosatellite, we observed that the antigravity soleus incurred the greatest changes compared with locomotor muscles. Proteomics data notably suggested mitochondrial dysfunction, metabolic and fiber type switching toward glycolytic type II fibers, structural alterations, and calcium signaling-related defects to be the main causes for decreased muscle performance in flown mice. Alterations of the protein balance, mTOR pathway, myogenesis, and apoptosis were expected to contribute to muscle atrophy. Moreover, several signs reflecting alteration of telomere maintenance, oxidative stress, and insulin resistance were found as possible additional deleterious effects. Finally, 8 days of recovery post flight were not sufficient to restore completely flight-induced changes. Thus in-depth proteomics analysis unraveled the complex and multifactorial remodeling of skeletal muscle structure and function during long-term space flight, which should help define combined sets of countermeasures before, during, and after the flight.


Assuntos
Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Proteoma/genética , Ausência de Peso/efeitos adversos , Animais , Apoptose/genética , Sinalização do Cálcio , Regulação da Expressão Gênica , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Desenvolvimento Muscular/genética , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Estresse Oxidativo , Proteoma/metabolismo , Voo Espacial , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Telômero/metabolismo , Telômero/patologia
13.
Diabetologia ; 60(8): 1491-1501, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28500394

RESUMO

AIMS/HYPOTHESIS: Physical inactivity has broad implications for human disease including insulin resistance, sarcopenia and obesity. The present study tested the hypothesis that (1) impaired mitochondrial respiration is linked with blunted insulin sensitivity and loss of muscle mass in healthy young men, and (2) resistive vibration exercise (RVE) would mitigate the negative metabolic effects of bed rest. METHODS: Participants (n = 9) were maintained in energy balance during 21 days of bed rest with RVE and without (CON) in a crossover study. Mitochondrial respiration was determined by high-resolution respirometry in permeabilised fibre bundles from biopsies of the vastus lateralis. A hyperinsulinaemic-euglycaemic clamp was used to determine insulin sensitivity, and body composition was assessed by dual-energy x-ray absorptiometry (DEXA). RESULTS: Body mass (-3.2 ± 0.5 kg vs -2.8 ± 0.4 kg for CON and RVE, respectively, p < 0.05), fat-free mass (-2.9 ± 0.5 kg vs -2.7 ± 0.5 kg, p < 0.05) and peak oxygen consumption ([Formula: see text]) (10-15%, p < 0.05) were all reduced following bed rest. Bed rest decreased insulin sensitivity in the CON group (0.04 ± 0.002 mg kgFFM-1 [pmol l-1] min-1 vs 0.03 ± 0.002 mg kgFFM-1 [pmol l-1] min-1 for baseline vs post-CON), while RVE mitigated this response (0.04 ± 0.003 mg kgFFM-1 [pmol l-1] min-1). Mitochondrial respiration (oxidative phosphorylation and electron transport system capacity) decreased in the CON group but not in the RVE group when expressed relative to tissue weight but not when normalised for citrate synthase activity. LEAK respiration, indicating a decrease in mitochondrial uncoupling, was the only component to remain significantly lower in the CON group after normalisation for citrate synthase. This was accompanied by a significant decrease in adenine nucleotide translocase protein content. CONCLUSIONS/INTERPRETATION: Reductions in muscle mitochondrial respiration occur concomitantly with insulin resistance and loss of muscle mass during bed rest and may play a role in the adaptations to physical inactivity. Significantly, we show that RVE is an effective strategy to partially prevent some of the deleterious metabolic effects of bed rest.


Assuntos
Repouso em Cama , Resistência à Insulina/fisiologia , Mitocôndrias/metabolismo , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Adulto , Composição Corporal/fisiologia , Estudos Cross-Over , Metabolismo Energético/fisiologia , Técnica Clamp de Glucose , Humanos , Masculino
14.
Clin Endocrinol (Oxf) ; 86(5): 747-754, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27809356

RESUMO

OBJECTIVE: Alterations in the hypothalamic-pituitary-thyroid axis have been reported following growth hormone (GH) replacement. The aim was to examine the relationship between changes in serum concentration of thyroid hormones and deiodinase activity in subcutaneous adipose tissue, before and after GH replacement. DESIGN: A prospective, observational study of patients receiving GH replacement as part of routine clinical care. PATIENTS: Twenty adult hypopituitary men. MEASUREMENTS: Serum TSH, thyroid hormones - free and total thyroxine (T4) and triiodothyronine (T3) and reverse T3, thyroglobulin and thyroid-binding globulin (TBG) levels were measured before and after GH substitution. Changes in serum hormone levels were compared to the activity of deiodinase isoenzymes (DIO1, DIO2 and DIO3) in subcutaneous adipose tissue. RESULTS: The mean daily dose of growth hormone (GH) was 0·34 ± 0·11 mg (range 0·15-0·5 mg). Following GH replacement, mean free T4 levels declined (-1·09 ± 1·99 pmol/l, P = 0·02). Reverse T3 levels also fell (-3·44 ± 1·42 ng/dl, P = 0·03) and free T3 levels increased significantly (+0·34 ± 0·15 pmol/l, P = 0·03). In subcutaneous fat, DIO2 enzyme activity declined; DIO1 and DIO3 activities remained unchanged following GH substitution. Serum TSH, thyroglobulin and TBG levels were unaltered by GH therapy. CONCLUSIONS: In vitro analysis of subcutaneous adipose tissue from hypopituitary human subjects demonstrates that GH replacement is associated with significant changes in deiodinase isoenzyme activity. However, the observed variation in enzyme activity does not explain the changes in the circulating concentration of thyroid hormones induced by GH replacement. It is possible that deiodinase isoenzymes are differentially regulated by GH in other tissues including liver and muscle.


Assuntos
Hormônio do Crescimento/farmacologia , Terapia de Reposição Hormonal/métodos , Hipopituitarismo/metabolismo , Gordura Subcutânea Abdominal/metabolismo , Adulto , Idoso , Hormônio do Crescimento/administração & dosagem , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Gordura Subcutânea Abdominal/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem
15.
Int J Behav Nutr Phys Act ; 14(1): 150, 2017 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-29100542

RESUMO

The establishment of the Determinants of Diet and Physical Activity (DEDIPAC) Knowledge Hub, 2013-2016, was the first action taken by the 'Healthy Diet for a Healthy Life' European Joint Programming Initiative. DEDIPAC aimed to provide better insight into the determinants of diet, physical activity and sedentary behaviour across the life course, i.e. insight into the causes of the causes of important, non-communicable diseases across Europe and beyond. DEDIPAC was launched in late 2013, and delivered its final report in late 2016. In this paper we give an overview of what was achieved in terms of furthering measurement and monitoring, providing overviews of the state-of-the-art in the field, and building toolboxes for further research and practice. Additionally, we propose some of the next steps that are now required to move forward in this field, arguing in favour of 1) sustaining the Knowledge Hub and developing it into a European virtual research institute and knowledge centre for determinants of behavioural nutrition and physical activity with close links to other parts of the world; 2) establishing a cohort study of families across all regions of Europe focusing specifically on the individual and contextual determinants of major, non-communicable disease; and 3) furthering DEDIPAC's work on nutrition, physical activity, and sedentary behaviour policy evaluation and benchmarking across Europe by aligning with other international initiatives and by supporting harmonisation of pan-European surveillance.


Assuntos
Dieta , Exercício Físico , Estudos de Coortes , Dieta Saudável , Europa (Continente) , Comportamentos Relacionados com a Saúde , Humanos , Pesquisa , Comportamento Sedentário
16.
BMC Public Health ; 16: 163, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26887323

RESUMO

BACKGROUND: Recent research shows that sedentary behaviour is associated with adverse cardio-metabolic consequences even among those considered sufficiently physically active. In order to successfully develop interventions to address this unhealthy behaviour, factors that influence sedentariness need to be identified and fully understood. The aim of this review is to identify individual, social, environmental, and policy-related determinants or correlates of sedentary behaviours among adults aged 18-65 years. METHODS: PubMed, Embase, CINAHL, PsycINFO and Web of Science were searched for articles published between January 2000 and September 2015. The search strategy was based on four key elements and their synonyms: (a) sedentary behaviour (b) correlates (c) types of sedentary behaviours (d) types of correlates. Articles were included if information relating to sedentary behaviour in adults (18-65 years) was reported. Studies on samples selected by disease were excluded. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42014009823). RESULTS: 74 original studies were identified out of 4041: 71 observational, two qualitative and one experimental study. Sedentary behaviour was primarily measured as self-reported screen leisure time and total sitting time. In 15 studies, objectively measured total sedentary time was reported: accelerometry (n = 14) and heart rate (n = 1). Individual level factors such as age, physical activity levels, body mass index, socio-economic status and mood were all significantly correlated with sedentariness. A trend towards increased amounts of leisure screen time was identified in those married or cohabiting while having children resulted in less total sitting time. Several environmental correlates were identified including proximity of green space, neighbourhood walkability and safety and weather. CONCLUSIONS: Results provide further evidence relating to several already recognised individual level factors and preliminary evidence relating to social and environmental factors that should be further investigated. Most studies relied upon cross-sectional design limiting causal inference and the heterogeneity of the sedentary measures prevented direct comparison of findings. Future research necessitates longitudinal study designs, exploration of policy-related factors, further exploration of environmental factors, analysis of inter-relationships between identified factors and better classification of sedentary behaviour domains.


Assuntos
Meio Ambiente , Atividades de Lazer , Comportamento Sedentário , Acelerometria , Adolescente , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Estudos Transversais , Política de Saúde , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Características de Residência , Fatores Socioeconômicos , Adulto Jovem
17.
Int J Behav Nutr Phys Act ; 11: 143, 2014 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-25731079

RESUMO

To address major societal challenges and enhance cooperation in research across Europe, the European Commission has initiated and facilitated 'joint programming'. Joint programming is a process by which Member States engage in defining, developing and implementing a common strategic research agenda, based on a shared vision of how to address major societal challenges that no Member State is capable of resolving independently. Setting up a Joint Programming Initiative (JPI) should also contribute to avoiding unnecessary overlap and repetition of research, and enable and enhance the development and use of standardised research methods, procedures and data management. The Determinants of Diet and Physical Activity (DEDIPAC) Knowledge Hub (KH) is the first act of the European JPI 'A Healthy Diet for a Healthy Life'. The objective of DEDIPAC is to contribute to improving understanding of the determinants of dietary, physical activity and sedentary behaviours. DEDIPAC KH is a multi-disciplinary consortium of 46 consortia and organisations supported by joint programming grants from 12 countries across Europe. The work is divided into three thematic areas: (I) assessment and harmonisation of methods for future research, surveillance and monitoring, and for evaluation of interventions and policies; (II) determinants of dietary, physical activity and sedentary behaviours across the life course and in vulnerable groups; and (III) evaluation and benchmarking of public health and policy interventions aimed at improving dietary, physical activity and sedentary behaviours. In the first three years, DEDIPAC KH will organise, develop, share and harmonise expertise, methods, measures, data and other infrastructure. This should further European research and improve the broad multi-disciplinary approach needed to study the interactions between multilevel determinants in influencing dietary, physical activity and sedentary behaviours. Insights will be translated into more effective interventions and policies for the promotion of healthier behaviours and more effective monitoring and evaluation of the impacts of such interventions.


Assuntos
Dieta , Promoção da Saúde/métodos , Atividade Motora , População Branca , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Comportamento Sedentário
18.
J Clin Pharmacol ; 64(4): 449-460, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37840155

RESUMO

Danuglipron (PF-06882961) is an oral, small-molecule glucagon-like peptide-1 receptor agonist in development for the treatment of type 2 diabetes (T2D) and obesity. Impaired renal function is prevalent in patients with T2D. This Phase 1, open-label study evaluated the effect of renal impairment on the pharmacokinetics, safety, and tolerability of danuglipron (20 mg) in healthy participants with normal renal function (estimated glomerular filtration rate [eGFR] unnormalized for body surface area: ≥90 mL/min), in participants with T2D and normal renal function (eGFR ≥90 mL/min), and in participants with T2D and mild (eGFR 60-89 mL/min), moderate (eGFR 30-59 mL/min), or severe (eGFR <30 mL/min) renal impairment (N = 39). Log-linear regression analyses and analyses of variance showed no evidence of a clinically significant effect of reduced renal function on danuglipron pharmacokinetics. Renal clearance of unchanged danuglipron was minimal (<1% across all renal function groups). Danuglipron pharmacokinetics were similar between healthy participants and participants with T2D and normal renal function. A single 20-mg oral dose of danuglipron was generally safe and well tolerated in all participant groups. In participants with T2D, renal impairment had no clinically meaningful effect on the pharmacokinetic, safety, and tolerability profiles of danuglipron, indicating that dose adjustment of danuglipron will not be required when administered to patients with T2D and reduced renal function.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insuficiência Renal/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Taxa de Filtração Glomerular , Área Sob a Curva
19.
Metabolism ; 155: 155910, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599278

RESUMO

BACKGROUND: Weight loss and lifestyle intervention improve glucose tolerance delaying the onset of type 2 diabetes (T2D), but individual responses are highly variable. Determining the predictive factors linked to the beneficial effects of weight loss on glucose tolerance could provide tools for individualized prevention plans. Thus, the aim was to investigate the relationship between pre-intervention values of insulin sensitivity and secretion and the improvement in glucose metabolism after weight loss. METHODS: In the DEXLIFE cohort (373 individuals at high risk of T2D, assigned 3:1 to a 12-week lifestyle intervention or a control arm, Trial Registration: ISRCTN66987085), K-means clustering and logistic regression analysis were performed based on pre-intervention indices of insulin sensitivity, insulin secretion (AUC-I), and glucose-stimulated insulin response (ratio of incremental areas of insulin and glucose, iAUC I/G). The response to the intervention was evaluated in terms of reduction of OGTT-glucose concentration. Clusters' validation was done in the prospective EGIR-RISC cohort (n = 1538). RESULTS: Four replicable clusters with different glycemic and metabolomic profiles were identified. Individuals had similar weight loss, but improvement in glycemic profile and ß-cell function was different among clusters, highly depending on pre-intervention insulin response to OGTT. Pre-intervention high insulin response was associated with the best improvement in AUC-G, while clusters with low AUC-I and iAUC I/G showed no beneficial effect of weight loss on glucose control, as also confirmed by the logistic regression model. CONCLUSIONS: Individuals with preserved ß-cell function and high insulin concentrations at baseline have the best improvement in glucose tolerance after weight loss.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Insulina , Fenótipo , Redução de Peso , Humanos , Redução de Peso/fisiologia , Células Secretoras de Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Masculino , Feminino , Insulina/sangue , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Estudos Prospectivos , Glicemia/metabolismo , Glicemia/análise , Adulto , Resistência à Insulina/fisiologia , Teste de Tolerância a Glucose , Intolerância à Glucose , Secreção de Insulina , Estilo de Vida , Idoso
20.
Lancet ; 379(9822): 1205-13, 2012 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-22421339

RESUMO

BACKGROUND: Persistent inflammation has been proposed to contribute to various stages in the pathogenesis of cardiovascular disease. Interleukin-6 receptor (IL6R) signalling propagates downstream inflammation cascades. To assess whether this pathway is causally relevant to coronary heart disease, we studied a functional genetic variant known to affect IL6R signalling. METHODS: In a collaborative meta-analysis, we studied Asp358Ala (rs2228145) in IL6R in relation to a panel of conventional risk factors and inflammation biomarkers in 125,222 participants. We also compared the frequency of Asp358Ala in 51,441 patients with coronary heart disease and in 136,226 controls. To gain insight into possible mechanisms, we assessed Asp358Ala in relation to localised gene expression and to postlipopolysaccharide stimulation of interleukin 6. FINDINGS: The minor allele frequency of Asp358Ala was 39%. Asp358Ala was not associated with lipid concentrations, blood pressure, adiposity, dysglycaemia, or smoking (p value for association per minor allele ≥0·04 for each). By contrast, for every copy of 358Ala inherited, mean concentration of IL6R increased by 34·3% (95% CI 30·4-38·2) and of interleukin 6 by 14·6% (10·7-18·4), and mean concentration of C-reactive protein was reduced by 7·5% (5·9-9·1) and of fibrinogen by 1·0% (0·7-1·3). For every copy of 358Ala inherited, risk of coronary heart disease was reduced by 3·4% (1·8-5·0). Asp358Ala was not related to IL6R mRNA levels or interleukin-6 production in monocytes. INTERPRETATION: Large-scale human genetic and biomarker data are consistent with a causal association between IL6R-related pathways and coronary heart disease. FUNDING: British Heart Foundation; UK Medical Research Council; UK National Institute of Health Research, Cambridge Biomedical Research Centre; BUPA Foundation.


Assuntos
Doença das Coronárias/genética , Doença das Coronárias/imunologia , Frequência do Gene , Variação Genética/genética , Receptores de Interleucina-6/genética , Transdução de Sinais/genética , Causalidade , Humanos , Mediadores da Inflamação/sangue , Fatores de Risco
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