ABSTRACT
As of April, 2023, 23 accelerated approvals for cancer indications granted by the US Food and Drug Administration (FDA) since 1992 have been withdrawn from the US market, with 17 (74%) of 23 withdrawn in the past 3 years. The marketing authorisation status of these indications in the EU has not been reported. A review of relevant documents from the FDA and the European Medicines Agency (EMA) was done to investigate whether the accelerated approvals for cancer indications withdrawn by the FDA have a marketing authorisation in the EU to date, and to compare the approval history of these indications by the EMA and FDA. We found that, as of April 20, 2023, nine (39%) of 23 withdrawn accelerated approvals for cancer indications in the USA have a marketing authorisation in the EU for a similar indication. By comparison, only two conditional marketing authorisations for cancer indications have been withdrawn from the EU; both are no longer approved in the USA. These findings indicate a discrepancy in the approval policies between the FDA and EMA and imply either that some patient groups in the USA do not get access to relevant medical treatment, or that some patient groups in the EU are treated with medicine without a positive benefit-risk balance. These discrepancies could potentially be reduced by increased collaboration and information sharing between the two agencies.
Subject(s)
Medicine , Neoplasms , United States , Humans , Neoplasms/drug therapy , Information Dissemination , Marketing , United States Food and Drug AdministrationABSTRACT
Metformin-induced glycolysis and lactate production can lead to acidosis as a life-threatening side effect, but slight increases in blood lactate levels in a physiological range were also reported in metformin-treated patients. However, how metformin increases systemic lactate concentrations is only partly understood. Because human skeletal muscle has a high capacity to produce lactate, the aim was to elucidate the dose-dependent regulation of metformin-induced lactate production and the potential contribution of skeletal muscle to blood lactate levels under metformin treatment. This was examined by using metformin treatment (16-776 µM) of primary human myotubes and by 17 days of metformin treatment in humans. As from 78 µM, metformin induced lactate production and secretion and glucose consumption. Investigating the cellular redox state by mitochondrial respirometry, we found metformin to inhibit the respiratory chain complex I (776 µM, P < 0.01) along with decreasing the [NAD+]:[NADH] ratio (776 µM, P < 0.001). RNA sequencing and phospho-immunoblot data indicate inhibition of pyruvate oxidation mediated through phosphorylation of the pyruvate dehydrogenase (PDH) complex (39 µM, P < 0.01). On the other hand, in human skeletal muscle, phosphorylation of PDH was not altered by metformin. Nonetheless, blood lactate levels were increased under metformin treatment (P < 0.05). In conclusion, the findings suggest that metformin-induced inhibition of pyruvate oxidation combined with altered cellular redox state shifts the equilibrium of the lactate dehydrogenase (LDH) reaction leading to a dose-dependent lactate production in primary human myotubes.NEW & NOTEWORTHY Metformin shifts the equilibrium of lactate dehydrogenase (LDH) reaction by low dose-induced phosphorylation of pyruvate dehydrogenase (PDH) resulting in inhibition of pyruvate oxidation and high dose-induced increase in NADH, which explains the dose-dependent lactate production of differentiated human skeletal muscle cells.
Subject(s)
Lactic Acid , Metformin , Humans , Lactic Acid/metabolism , Metformin/pharmacology , NAD/metabolism , Oxidation-Reduction , Muscle Fibers, Skeletal/metabolism , Pyruvates , Oxidoreductases/metabolism , Lactate Dehydrogenases/metabolismABSTRACT
Perceived physical exertion is increased when exercise is performed on metformin treatment, but the clinical relevance of this is unknown. In this post hoc analysis of a randomized, controlled trial, we investigated whether metformin treatment was associated with lower levels of free-living physical activity. Ninety individuals with overweight/obesity (BMI>25 m2/kg) and HbA1c-defined prediabetes (39-47 mmol/mol) were randomized to treatment with dapagliflozin (SGLT2-inhibitor; 10 mg once daily, n=30), metformin (850 mg twice daily, n=30) or no treatment (control, n=30) for 13 weeks in a parallel-group, open-label trial. Before (baseline), during (6 weeks) and immediately after (13 weeks) cessation of treatment, a 6-day assessment of physical activity and sedentary behaviour was performed using accelerometer-based physical activity monitors. Intention-to-treat analyses revealed no within-group changes or differences in change between the groups for any measures of physical activity or sedentary behaviour at neither 6 nor 13 weeks. Short-term metformin treatment does not reduce free-living physical activity level in individuals with overweight/obesity and HbA1c-defined prediabetes.
Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Prediabetic State , Humans , Metformin/therapeutic use , Hypoglycemic Agents/therapeutic use , Prediabetic State/drug therapy , Overweight/drug therapy , Sedentary Behavior , Drug Therapy, Combination , Double-Blind Method , Obesity/drug therapy , Exercise , Treatment Outcome , Blood Glucose/analysisABSTRACT
AIMS/HYPOTHESIS: The aim of this parallel-group, double-blinded (study personnel and participants), randomised clinical trial was to assess the interaction between metformin and exercise training on postprandial glucose in glucose-intolerant individuals. METHODS: Glucose-intolerant (2 h OGTT glucose of 7.8-11.0 mmol/l and/or HbA1c of 39-47 mmol/mol [5.7-6.5%] or glucose-lowering-medication naive type 2 diabetes), overweight/obese (BMI 25-42 kg/m2) individuals were randomly allocated to a placebo study group (PLA, n = 15) or a metformin study group (MET, n = 14), and underwent 3 experimental days: BASELINE (before randomisation), MEDICATION (after 3 weeks of metformin [2 g/day] or placebo treatment) and TRAINING (after 12 weeks of exercise training in combination with metformin/placebo treatment). Training consisted of supervised bicycle interval sessions with a mean intensity of 64% of Wattmax for 45 min, 4 times/week. The primary outcome was postprandial glucose (mean glucose concentration) during a mixed meal tolerance test (MMTT), which was assessed on each experimental day. For within-group differences, a group × time interaction was assessed using two-way repeated measures ANOVA. Between-group changes of the outcomes at different timepoints were compared using unpaired two-tailed Student's t tests. RESULTS: Postprandial glucose improved from BASELINE to TRAINING in both the PLA group and the MET group (∆PLA: -0.7 [95% CI -1.4, 0.0] mmol/l, p = 0.05 and ∆MET: -0.7 [-1.5, -0.0] mmol/l, p = 0.03), with no between-group difference (p = 0.92). In PLA, the entire reduction was seen from MEDICATION to TRAINING (-0.8 [-1.3, -0.1] mmol/l, p = 0.01). Conversely, in MET, the entire reduction was observed from BASELINE to MEDICATION (-0.9 [-1.6, -0.2] mmol/l, p = 0.01). The reductions in mean glucose concentration during the MMTT from BASELINE to TRAINING were dependent on differential time effects: in the PLA group, a decrease was observed at timepoint (t) = 120 min (p = 0.009), whereas in the MET group, a reduction occurred at t = 30 min (p < 0.001). VÌO2peak increased 15% (4.6 [3.3, 5.9] ml kg-1 min-1, p < 0.0001) from MEDICATION to TRAINING and body weight decreased (-4.0 [-5.2, -2.7] kg, p < 0.0001) from BASELINE to TRAINING, with no between-group differences (p = 0.7 and p = 0.5, respectively). CONCLUSIONS/INTERPRETATION: Metformin plus exercise training was not superior to exercise training alone in improving postprandial glucose. The differential time effects during the MMTT suggest an interaction between the two modalities. FUNDING: The Beckett foundation, A.P Møller Foundation, DDA, the Research Foundation of Rigshospitalet and Trygfonden. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03316690). Graphical abstract.
Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/therapy , Exercise/physiology , Glucose Intolerance/therapy , Hypoglycemic Agents/therapeutic use , Metformin/therapeutic use , Postprandial Period , Prediabetic State/therapy , Adult , Combined Modality Therapy , Diabetes Mellitus, Type 2/metabolism , Double-Blind Method , Female , Glucose Intolerance/metabolism , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Prediabetic State/metabolismABSTRACT
AIMS/HYPOTHESIS: We aimed to investigate the short-term efficacy and safety of three glucose-lowering interventions in overweight or obese individuals with prediabetes defined by HbA1c. METHODS: The PRE-D Trial was a randomised, controlled, parallel, multi-arm, open-label, non-blinded trial performed at Steno Diabetes Center Copenhagen, Gentofte, Denmark. One hundred and twenty participants with BMI ≥25 kg/m2, 30-70 years of age, and prediabetes (HbA1c 39-47 mmol/mol [5.7-6.4%]) were randomised 1:1:1:1 to dapagliflozin (10 mg once daily), metformin (1700 mg daily), interval-based exercise (5 days/week, 30 min/session) or control (habitual lifestyle). Participants were examined at baseline and at 6, 13 and 26 weeks after randomisation. The primary outcome was the 13 week change in glycaemic variability (calculated as mean amplitude of glycaemic excursions [MAGE]) determined using a continuous glucose monitoring system (pre-specified minimal clinically important difference in MAGE â¼30%). RESULTS: One hundred and twelve participants attended the examination at 13 weeks and 111 attended the follow-up visit at 26 weeks. Compared with the control group, there was a small decrease in MAGE in the dapagliflozin group (17.1% [95% CI 0.7, 30.8], p = 0.042) and a small, non-significant, reduction in the exercise group (15.3% [95% CI -1.2, 29.1], p = 0.067), whereas MAGE was unchanged in the metformin group (0.1% [95% CI -16.1, 19.4], p = 0.991)). Compared with the metformin group, MAGE was 17.2% (95% CI 0.8, 30.9; p = 0.041) lower in the dapagliflozin group and 15.4% (95% CI -1.1, 29.1; p = 0.065) lower in the exercise group after 13 weeks, with no difference between exercise and dapagliflozin (2.2% [95% CI -14.8, 22.5], p = 0.815). One serious adverse event occurred in the control group (lung cancer). CONCLUSIONS/INTERPRETATION: Treatment with dapagliflozin and interval-based exercise lead to similar but small improvements in glycaemic variability compared with control and metformin therapy. The clinical importance of these findings in prediabetes is uncertain. TRIAL REGISTRATION: ClinicalTrials.gov NCT02695810 FUNDING: The study was funded by the Novo Nordisk Foundation, AstraZeneca AB, the Danish Innovation Foundation, the University of Copenhagen and Ascensia Diabetes Care Denmark ApS Graphical abstract.
Subject(s)
Benzhydryl Compounds/therapeutic use , Blood Glucose/analysis , Exercise , Glucosides/therapeutic use , Metformin/therapeutic use , Overweight/blood , Prediabetic State/therapy , Adult , Aged , Body Mass Index , Denmark , Glycated Hemoglobin/analysis , Glycemic Control/methods , Humans , Hypoglycemic Agents/therapeutic use , Middle Aged , Obesity/blood , Prediabetic State/drug therapy , Treatment OutcomeABSTRACT
AIM: To assess the effects of dapagliflozin, metformin and exercise treatment on changes in plasma glucagon concentrations in individuals with overweight and HbA1c-defined prediabetes. MATERIALS AND METHODS: One-hundred and twenty individuals with overweight (body mass index ≥ 25 kg/m2 ) and prediabetes (HbA1c of 39-47 mmol/mol) were randomized to a 13-week intervention with dapagliflozin (10 mg once daily), metformin (850 mg twice daily), exercise (30 minutes of interval training 5 days per week) or control (habitual living). A 75-g oral glucose tolerance test (OGTT) (0, 30, 60 and 120 minutes) was administered at baseline, at 13 weeks (end of intervention) and at 26 weeks (end of follow-up). Linear mixed effects models with participant-specific random intercepts were used to investigate associations of the interventions with fasting plasma glucagon concentration, insulin/glucagon ratio and glucagon suppression during the OGTT. RESULTS: At baseline, the median (Q1; Q3) age was 62 (54; 68) years, median fasting plasma glucagon concentration was 11 (7; 15) pmol/L, mean (SD) HbA1c was 40.9 (2.3) mmol/mol and 56% were women. Compared with the control group, fasting glucagon did not change in any of the groups from baseline to the end of the intervention (dapagliflozin group: -5% [95% CI: -29; 26]; exercise group: -8% [95% CI: -31; 24]; metformin group: -2% [95% CI: -27; 30]). Likewise, there were no differences in insulin/glucagon ratio and glucagon suppression during the OGTT between the groups. CONCLUSIONS: In individuals with prediabetes, 13 weeks of treatment with dapagliflozin, metformin or exercise was not associated with changes in fasting or post-OGTT glucagon concentrations.
Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Prediabetic State , Aged , Benzhydryl Compounds/therapeutic use , Blood Glucose , Diabetes Mellitus, Type 2/drug therapy , Double-Blind Method , Drug Therapy, Combination , Female , Glucagon/therapeutic use , Glucosides , Humans , Hypoglycemic Agents/therapeutic use , Male , Metformin/therapeutic use , Middle Aged , Prediabetic State/drug therapyABSTRACT
AIMS/HYPOTHESIS: The aim was to investigate whether an intensive lifestyle intervention, with high volumes of exercise, improves beta cell function and to explore the role of low-grade inflammation and body weight. METHODS: This was a randomised, assessor-blinded, controlled trial. Ninety-eight individuals with type 2 diabetes (duration <10 years), BMI of 25-40 kg/m2, no use of insulin and taking fewer than three glucose-lowering medications were randomised (2:1) to either the standard care plus intensive lifestyle group or the standard care alone group. Standard care consisted of individual guidance on disease management, lifestyle advice and blinded regulation of medication following a pre-specified algorithm. The intensive lifestyle intervention consisted of aerobic exercise sessions that took place 5-6 times per week, combined with resistance exercise sessions 2-3 times per week, with a concomitant dietary intervention aiming for a BMI of 25 kg/m2. In this secondary analysis beta cell function was assessed from the 2 h OGTT-derived disposition index, which is defined as the product of the Matsuda and the insulinogenic indices. RESULTS: At baseline, individuals were 54.8 years (SD 8.9), 47% women, type 2 diabetes duration 5 years (IQR 3-8) and HbA1c was 49.3 mmol/mol (SD 9.2); 6.7% (SD 0.8). The intensive lifestyle group showed 40% greater improvement in the disposition index compared with the standard care group (ratio of geometric mean change [RGM] 1.40 [95% CI 1.01, 1.94]) from baseline to 12 months' follow-up. Plasma concentration of IL-1 receptor antagonist (IL-1ra) decreased 30% more in the intensive lifestyle group compared with the standard care group (RGM 0.70 [95% CI 0.58, 0.85]). Statistical single mediation analysis estimated that the intervention effect on the change in IL-1ra and the change in body weight explained to a similar extent (59%) the variance in the intervention effect on the disposition index. CONCLUSIONS/INTERPRETATION: Our findings show that incorporating an intensive lifestyle intervention, with high volumes of exercise, in individuals with type 2 diabetes has the potential to improve beta cell function, associated with a decrease in low-grade inflammation and/or body weight. TRIAL REGISTRATION: ClinicalTrials.gov NCT02417012 Graphical abstract.
Subject(s)
Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/therapy , Blood Glucose/metabolism , Body Weight/physiology , Exercise/physiology , Glycemic Control , Humans , Hypoglycemic Agents/therapeutic use , Insulin/blood , Middle AgedABSTRACT
AIMS/HYPOTHESIS: IL-6 is a cytokine with various effects on metabolism. In mice, IL-6 improved beta cell function and glucose homeostasis via upregulation of glucagon-like peptide 1 (GLP-1), and IL-6 release from muscle during exercise potentiated this beneficial increase in GLP-1. This study aimed to identify whether exercise-induced IL-6 has a similar effect in humans. METHODS: In a multicentre, double-blind clinical trial, we randomly assigned patients with type 2 diabetes or obesity to intravenous tocilizumab (an IL-6 receptor antagonist) 8 mg/kg every 4 weeks, oral sitagliptin (a dipeptidyl peptidase-4 inhibitor) 100 mg daily or double placebos (a placebo saline infusion every 4 weeks and a placebo pill once daily) during a 12 week training intervention. The primary endpoints were the difference in change of active GLP-1 response to an acute exercise bout and change in the AUC for the concentration-time curve of active GLP-1 during mixed meal tolerance tests at baseline and after the training intervention. RESULTS: Nineteen patients were allocated to tocilizumab, 17 to sitagliptin and 16 to placebos. During the acute exercise bout active GLP-1 levels were 26% lower with tocilizumab (multiplicative effect: 0.74 [95% CI 0.56, 0.98], p = 0.034) and 53% higher with sitagliptin (1.53 [1.15, 2.03], p = 0.004) compared with placebo. After the 12 week training intervention, the active GLP-1 AUC with sitagliptin was about twofold that with placebo (2.03 [1.56, 2.62]; p < 0.001), while GLP-1 AUC values showed a small non-significant decrease of 13% at 4 weeks after the last tocilizumab infusion (0.87 [0.67, 1.12]; p = 0.261). CONCLUSIONS/INTERPRETATION: IL-6 is implicated in the regulation of GLP-1 in humans. IL-6 receptor blockade lowered active GLP-1 levels in response to a meal and an acute exercise bout in a reversible manner, without lasting effects beyond IL-6 receptor blockade. TRIAL REGISTRATION: Clinicaltrials.gov NCT01073826. FUNDING: Danish National Research Foundation. Danish Council for Independent Research. Novo Nordisk Foundation. Danish Centre for Strategic Research in Type 2 Diabetes. European Foundation for the Study of Diabetes. Swiss National Research Foundation.
Subject(s)
Diabetes Mellitus, Type 2/metabolism , Exercise/physiology , Glucagon-Like Peptide 1/metabolism , Antibodies, Monoclonal, Humanized/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Double-Blind Method , Female , Humans , Interleukin-6/metabolism , Male , Obesity/drug therapy , Obesity/metabolism , Receptors, Interleukin-6/metabolism , Sitagliptin Phosphate/therapeutic useABSTRACT
Acute and adaptive changes in systemic markers of oxidatively generated nucleic acid modifications (i.e., 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo)) as well as inflammatory cytokines (i.e., C-reactive protein, interleukin-6, interleukin-10, and tumour necrosis factor alpha), a liver hormone (i.e., fibroblast growth factor 21 (FGF21)), and bone metabolism markers (sclerostin, osteocalcin, C-terminal telopeptide, and N-terminal propeptide of type 1 procollagen) were investigated following a marathon in 20 study participants. Immediate changes were observed in inflammatory cytokines, FGF21, and bone metabolism markers following the marathon. In contrast, no immediate changes in urinary excretion of 8-oxodG and 8-oxoGuo were evident. Four days after the marathon, decreased urinary excretion of 8-oxodG (-2.9 (95% CI -4.8;-1.1) nmol/24 h, P < 0.01) and 8-oxoGuo (-5.8 (95% CI -10.3;-1.3) nmol/24 h, P = 0.02) was observed. The excretion rate of 8-oxodG remained decreased 7 days after the marathon compared to baseline (-2.3 (95%CI -4.3;-0.4) nmol/24 h, P = 0.02), whereas the excretion rate of 8-oxoGuo was normalized. In conclusion marathon participation immediately induced a considerable inflammatory response, but did not increase excretion rates of oxidatively generated nucleic acid modifications. In fact, a delayed decrease in oxidatively generated nucleic acid modifications was observed suggesting adaptive antioxidative effects following exercise. ABBREVIATIONS: 8-oxodG: 8-oxo-7,8-dihydro-2'-deoxyguanosine; 8-oxoGuo: 8-oxo-7,8-dihydroguanosine; CI: confidence interval; CTX: C-terminal telopeptide of type 1 collagen; DXA: dual-energy X-ray absorptiometry; ELISA: enzyme-linked immunosorbent assay; FGF21: Fibroblast growth factor 21; h: hour; hsCRP: high sensitivity C-reactive protein; IL: interleukin; IQR: interquartile range; MS: mass spectrometry: P1NP: N-terminal propeptide of type 1 procollagen; TNFα: tumour necrosis factor alpha; UPLC: ultra-performance liquid chromatography.
Subject(s)
Inflammation/blood , Inflammation/urine , Oxidative Stress , Physical Endurance/physiology , Running/physiology , 8-Hydroxy-2'-Deoxyguanosine/urine , Biomarkers/blood , Biomarkers/urine , Bone Remodeling , Creatinine/urine , Cytokines/blood , Humans , Male , Time Factors , Young AdultABSTRACT
AIM: To investigate whether an intensive lifestyle intervention induces partial or complete type 2 diabetes (T2D) remission. MATERIALS AND METHODS: In a secondary analysis of a randomized, assessor-blinded, single-centre trial, people with non-insulin-dependent T2D (duration <10 years), were randomly assigned (2:1, stratified by sex, from April 2015 to August 2016) to a lifestyle intervention group (n = 64) or a standard care group (n = 34). The primary outcome was partial or complete T2D remission, defined as non-diabetic glycaemia with no glucose-lowering medication at the outcome assessments at both 12 and 24 months from baseline. All participants received standard care, with standardized, blinded, target-driven medical therapy during the initial 12 months. The lifestyle intervention included 5- to 6-weekly aerobic and combined aerobic and strength training sessions (30-60 minutes) and individual dietary plans aiming for body mass index ≤25 kg/m2 . No intervention was provided during the 12-month follow-up period. RESULTS: Of the 98 randomized participants, 93 completed follow-up (mean [SD] age 54.6 [8.9] years; 46 women [43%], mean [SD] baseline glycated haemoglobin 49.3 [9.3] mmol/mol). At follow-up, 23% of participants (n = 14) in the intervention and 7% (n = 2) in the standard care group met the criteria for any T2D remission (odds ratio [OR] 4.4, 95% confidence interval [CI] 0.8-21.4]; P = 0.08). Assuming participants lost to follow-up (n = 5) had relapsed, the OR for T2D remission was 4.4 (95% CI 1.0-19.8; P = 0.048). CONCLUSIONS: The statistically nonsignificant threefold increased remission rate of T2D in the lifestyle intervention group calls for further large-scale studies to understand how to implement sustainable lifestyle interventions among people with T2D.
Subject(s)
Diabetes Mellitus, Type 2/therapy , Diet/methods , Exercise Therapy/methods , Life Style , Adult , Aged , Female , Humans , Male , Middle Aged , Treatment Outcome , Weight Loss/physiologyABSTRACT
The majority of T2D cases are preventable through a healthy lifestyle, leaving little room for questions that lifestyle should be the first line of defence in the fight against the development of T2D. However, when it comes to the clinical care of T2D, the potential efficacy of lifestyle is much less clear-cut, both in terms of impacting the pathological metabolic biomarkers of the disease, and long-term complications. A healthy diet, high leisure-time physical activity, and exercise are considered to be cornerstones albeit adjunct to drug therapy in the management of T2D. The prescription and effective implementation of structured exercise and other lifestyle interventions in the treatment of T2D have not been routinely used. In this article, we critically appraise and debate our reflections as to why exercise and physical activity may not have reached the status of a viable and effective treatment in the clinical care of T2D to the same extent as pharmaceutical drugs. We argue that the reason why exercise therapy is not utilized to a satisfactory degree is multifaceted and primarily relates to a "vicious cycle" with lack of proven efficacy on T2D complications and a lack of proven effectiveness on risk factors in the primary care of T2D. Furthermore, there is a lack of experimental research establishing the optimal dose of exercise. This precludes widespread and sustained implementation of physical activity and exercise in the clinical treatment of T2D will not succeed.
Subject(s)
Diabetes Mellitus, Type 2/therapy , Exercise Therapy , Hypoglycemic Agents/therapeutic use , Humans , Life StyleABSTRACT
AIMS/HYPOTHESIS: The aim of this study was to evaluate the effects of oxygen consumption-matched short-term interval walking training (IWT) vs continuous walking training (CWT) on glycaemic control, including glycaemic variability, in individuals with type 2 diabetes. We also assessed whether any training-induced improvements in glycaemic control were associated with systemic oxidative stress levels. METHODS: Participants (n = 14) with type 2 diabetes completed a crossover trial using three interventions (control intervention [CON], CWT and IWT), each lasting 2 weeks. These were performed in a randomised order (computerised generated randomisation) and separated by washout periods of 4 or 8 weeks after CON or training interventions, respectively. Training included ten supervised treadmill sessions, lasting 60 min/session, and was performed at the research facility. CWT was performed at moderate walking speed (75.6% ± 2.5% of walking peak oxygen consumption [[Formula: see text]]), while IWT was performed as alternating 3 min repetitions at slow (58.9% ± 2.0% [Formula: see text]) and fast (90.0% ± 3.6% [Formula: see text]) walking speed. Before and after each intervention, the following was assessed: 24 h continuous glucose monitoring (CGM) and urinary free 8-iso prostaglandin F2α (8-iso PGF2α; a marker for oxidative stress), physical fitness and body composition. Neither participants nor assessors were blinded to the interventions. RESULTS: No intervention-induced changes were seen in physical fitness or body composition. Compared with baseline, IWT reduced mean glucose levels non-significantly (-0.7 ± 0.3 mmol/l, p = 0.08) and significantly reduced maximum glucose levels (-1.8 ± 0.5 mmol/l, p = 0.04) and mean amplitude of glycaemic excursions (MAGE; -1.7 ± 0.4 mmol/l, p = 0.02), whereas no significant within-group changes were seen with CON or CWT. Although 8-iso PGF2α was associated with minimum glucose levels at baseline, no change in 8-iso PGF2α was seen with any intervention, nor were there any associations between changes in 8-iso PGF2α and changes in glycaemic control (p > 0.05 for all). No adverse effects were observed with any of the interventions. CONCLUSIONS/INTERPRETATION: Short-term IWT, but not CWT, improves CGM-derived measures of glycaemic control independent of changes in physical fitness and body composition in individuals with type 2 diabetes. Systemic oxidative stress levels are unaffected by short-term walking and changes in oxidative stress levels are not associated with changes in glycaemic control. TRIAL REGISTRATION: ClinicalTrials.gov NCT02320526 FUNDING : The Centre for Physical Activity Research (CFAS) is supported by a grant from TrygFonden. During the study period, the Centre of Inflammation and Metabolism (CIM) was supported by a grant from the Danish National Research Foundation (DNRF55). The study was further supported by grants from Diabetesforeningen, Augustinusfonden and Krista og Viggo Petersens Fond. CIM/CFAS is a member of the Danish Center for Strategic Research in Type 2 Diabetes (DD2; the Danish Council for Strategic Research, grant no. 09-067009 and 09-075724). MR-L was supported by a post-doctoral grant from the Danish Diabetes Academy supported by the Novo Nordisk Foundation.
Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Walking/physiology , Aged , Body Composition/physiology , Cross-Over Studies , Diabetes Mellitus, Type 2/physiopathology , Exercise/physiology , Female , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Oxidative Stress/physiologyABSTRACT
AIMS/HYPOTHESIS: The role of glucose effectiveness (S G) in training-induced improvements in glucose metabolism in individuals with type 2 diabetes is unknown. The objectives and primary outcomes of this study were: (1) to assess the efficacy of interval walking training (IWT) and continuous walking training (CWT) on S G and insulin sensitivity (S I) in individuals with type 2 diabetes; and (2) to assess the association of changes in S G and S I with changes in glycaemic control. METHODS: Fourteen participants with type 2 diabetes underwent three trials (IWT, CWT and no training) in a crossover study. Exclusion criteria were exogenous insulin treatment, smoking, pregnancy, contraindications to structured physical activity and participation in recurrent training (>90 min/week). The trials were performed in a randomised order (computerised-generated randomisation). IWT and CWT consisted of ten supervised treadmill walking sessions, each lasting 60 min, over 2 weeks. IWT was performed as repeated cycles of 3 min slow walking and 3 min fast walking (aiming for 54% and 89% of [Formula: see text], respectively, which was measured during the last minute of each interval), and CWT was performed aiming for a moderate walking speed (73% of [Formula: see text]). A two-step (pancreatic and hyperinsulinaemic) hyperglycaemic clamp was implemented before and after each trial. All data were collected in a hospitalised setting. Neither participants nor assessors were blinded to the trial interventions. RESULTS: Thirteen individuals completed all procedures and were included in the analyses. IWT improved S G (mean ± SEM: 0.6 ± 0.1 mg kg-1 min-1, p < 0.05) but not S I (p > 0.05), whereas CWT matched for energy expenditure and time duration improved neither S G nor S I (both p > 0.05). Changes in S G, but not in S I, were associated with changes in mean (ß = -0.62 ± 0.23, r 2 = 0.17, p < 0.01) and maximum (ß = -1.18 ± 0.52, r 2 = 0.12, p < 0.05) glucose levels during 24 h continuous glucose monitoring. CONCLUSIONS/INTERPRETATION: Two weeks of IWT, but not CWT, improves S G but not S I in individuals with type 2 diabetes. Moreover, changes in S G are associated with changes in glycaemic control. Therefore, increased S G is likely an important mechanism by which training improves glycaemic control in individuals with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT02320526 FUNDING: CFAS is supported by a grant from TrygFonden. During the study period, the Centre of Inflammation and Metabolism (CIM) was supported by a grant from the Danish National Research Foundation (DNRF55). The study was further supported by grants from Diabetesforeningen, Augustinusfonden and Krista og Viggo Petersens Fond. CIM/CFAS is a member of DD2-the Danish Center for Strategic Research in Type 2 Diabetes (the Danish Council for Strategic Research, grant no. 09-067009 and 09-075724).
Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/physiopathology , Insulin/blood , Aged , Body Composition/physiology , C-Peptide/blood , Cross-Over Studies , Energy Metabolism/physiology , Exercise/physiology , Female , Humans , Insulin Resistance/physiology , Kinetics , Male , Middle Aged , Walking/physiologyABSTRACT
The soluble receptor for advanced glycation end products (sRAGE) may be protective against inflammation associated with obesity and type 2 diabetes (T2DM). The aim of this study was to determine the distribution of sRAGE isoforms and whether sRAGE isoforms are associated with risk of T2DM development in subjects spanning the glucose tolerance continuum. In this retrospective analysis, circulating total sRAGE and endogenous secretory RAGE (esRAGE) were quantified via ELISA, and cleaved RAGE (cRAGE) was calculated in 274 individuals stratified by glucose tolerance status (GTS) and obesity. Group differences were probed by ANOVA, and multivariate ordinal logistic regression was used to test the association between sRAGE isoform concentrations and the proportional odds of developing diabetes, vs. normal glucose tolerance (NGT) or impaired glucose tolerance (IGT). When stratified by GTS, total sRAGE, cRAGE, and esRAGE were all lower with IGT and T2DM, while the ratio of cRAGE to esRAGE (cRAGE:esRAGE) was only lower (P < 0.01) with T2DM compared with NGT. When stratified by GTS and obesity, cRAGE:esRAGE was higher with obesity and lower with IGT (P < 0.0001) compared with lean, NGT. In ordinal logistic regression models, greater total sRAGE (odds ratio, 0.91; P < 0.01) and cRAGE (odds ratio, 0.84; P < 0.01) were associated with lower proportional odds of developing T2DM. Reduced values of sRAGE isoforms observed with both obesity and IGT are independently associated with greater proportional odds of developing T2DM. The mechanisms by which each respective isoform contributes to obesity and insulin resistance may reveal novel treatment strategies for diabetes.
Subject(s)
Diabetes Mellitus, Type 2/blood , Glucose Intolerance/blood , Obesity/blood , Receptor for Advanced Glycation End Products/blood , Adolescent , Adult , Aged , Aging/metabolism , Blood Glucose/analysis , Body Mass Index , Diabetes Mellitus, Type 2/complications , Disease Progression , Female , Glucose Intolerance/complications , Glucose Tolerance Test , Glycated Hemoglobin/analysis , Humans , Isomerism , Male , Middle Aged , Obesity/complications , Overweight/blood , Overweight/complications , Receptor for Advanced Glycation End Products/chemistry , Retrospective Studies , Young AdultABSTRACT
Importance: It is unclear whether a lifestyle intervention can maintain glycemic control in patients with type 2 diabetes. Objective: To test whether an intensive lifestyle intervention results in equivalent glycemic control compared with standard care and, secondarily, leads to a reduction in glucose-lowering medication in participants with type 2 diabetes. Design, Setting, and Participants: Randomized, assessor-blinded, single-center study within Region Zealand and the Capital Region of Denmark (April 2015-August 2016). Ninety-eight adult participants with non-insulin-dependent type 2 diabetes who were diagnosed for less than 10 years were included. Participants were randomly assigned (2:1; stratified by sex) to the lifestyle group (n = 64) or the standard care group (n = 34). Interventions: All participants received standard care with individual counseling and standardized, blinded, target-driven medical therapy. Additionally, the lifestyle intervention included 5 to 6 weekly aerobic training sessions (duration 30-60 minutes), of which 2 to 3 sessions were combined with resistance training. The lifestyle participants received dietary plans aiming for a body mass index of 25 or less. Participants were followed up for 12 months. Main Outcomes and Measures: Primary outcome was change in hemoglobin A1c (HbA1c) from baseline to 12-month follow-up, and equivalence was prespecified by a CI margin of ±0.4% based on the intention-to-treat population. Superiority analysis was performed on the secondary outcome reductions in glucose-lowering medication. Results: Among 98 randomized participants (mean age, 54.6 years [SD, 8.9]; women, 47 [48%]; mean baseline HbA1c, 6.7%), 93 participants completed the trial. From baseline to 12-month follow-up, the mean HbA1c level changed from 6.65% to 6.34% in the lifestyle group and from 6.74% to 6.66% in the standard care group (mean between-group difference in change of -0.26% [95% CI, -0.52% to -0.01%]), not meeting the criteria for equivalence (P = .15). Reduction in glucose-lowering medications occurred in 47 participants (73.5%) in the lifestyle group and 9 participants (26.4%) in the standard care group (difference, 47.1 percentage points [95% CI, 28.6-65.3]). There were 32 adverse events (most commonly musculoskeletal pain or discomfort and mild hypoglycemia) in the lifestyle group and 5 in the standard care group. Conclusions and Relevance: Among adults with type 2 diabetes diagnosed for less than 10 years, a lifestyle intervention compared with standard care resulted in a change in glycemic control that did not reach the criterion for equivalence, but was in a direction consistent with benefit. Further research is needed to assess superiority, as well as generalizability and durability of findings. Trial Registration: clinicaltrials.gov Identifier: NCT02417012.
Subject(s)
Caloric Restriction , Diabetes Mellitus, Type 2/therapy , Exercise , Hypoglycemic Agents/administration & dosage , Life Style , Adult , Aged , Counseling , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/drug therapy , Female , Glycated Hemoglobin/analysis , Humans , Intention to Treat Analysis , Male , Middle Aged , Single-Blind Method , Weight LossABSTRACT
Type 2 diabetes mellitus (T2DM) is associated with metabolic dysregulation and chronic inflammation, and regular exercise may provide a strong stimulus for improving both. In this review, we first discuss the link between inflammation and metabolism. Next, we give an update on the clinical metabolic effects of exercise in T2DM patients with special focus on which parameters to consider for optimizing metabolic improvements. We then discuss the mechanisms whereby exercise exerts its anti-inflammatory and related metabolic effects. Evidence exists that interleukin (IL)-1ß is involved in pancreatic ß-cell damage, whereas tumor necrosis factor (TNF)-α appears to be a key molecule in peripheral insulin resistance. Mechanistic studies in humans suggest that moderate acute elevations in IL-6, as provoked by exercise, exert direct anti-inflammatory effects by an inhibition of TNF-α and by stimulating IL-1ra (IL-1 receptor antagonist), thereby limiting IL-1ß signaling. In addition, IL-6 has direct impact on glucose and lipid metabolism. Moreover, indirect anti-inflammatory effects of exercise may be mediated via improvements in, for example, body composition. While waiting for the outcome of long-term randomized clinical training studies with hard end points, it should be emphasized that physical activity represents a natural strong anti-inflammatory and metabolism-improving strategy with minor side effects.
Subject(s)
Diabetes Mellitus, Type 2/metabolism , Exercise Therapy , Exercise/physiology , Inflammation/metabolism , Animals , Diabetes Mellitus, Type 2/immunology , Diabetes Mellitus, Type 2/therapy , Humans , Inflammation/immunology , Inflammation/therapy , Interleukin 1 Receptor Antagonist Protein/metabolism , Interleukin-1beta/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
PURPOSE OF REVIEW: Skeletal muscle is gaining increased attention as an endocrine organ. Recently, novel myokines and new effects of already established myokines have been identified. The objective of this review is to give an update on the recent advances in the field. RECENT FINDINGS: Several hundred putative myokines have been described, some of which are induced by contraction and differentially regulated between healthy and metabolically diseased individuals. Interleukin-6 (IL-6) is the prototype myokine, which was identified as a muscle-derived cytokine 15 years ago. Recently, IL-6 has been linked to ß-cell survival and inhibition of cancer-cell growth. Moreover, trans-signaling appears to determine whether IL-6 acts as a proinflammatory or an anti-inflammatory cytokine. Irisin has been shown to be a secreted myokine, which contribute to circulating concentrations dependent on training status. IL-15 has been established as a cytokine mediating cross-talk between skeletal muscle and skin tissue, and decorin has been characterized as a contraction-induced myokine which apparently is differentially regulated between healthy and dysglycemic individuals. SUMMARY: Skeletal muscle is an endocrine organ which, by the release of myokines, may influence metabolism in virtually all organs in the body. This knowledge may potentially open up for the possibility of designing new drugs that mimic the effects of myokine signaling.
Subject(s)
Endocrine System/metabolism , Gene Expression Regulation, Developmental , Muscle, Skeletal/metabolism , Animals , Cytokines/genetics , Cytokines/metabolism , Endocrine System/growth & development , Endocrine System/immunology , Endocrine System Diseases/immunology , Endocrine System Diseases/metabolism , Endocrine System Diseases/prevention & control , Exercise , Healthy Lifestyle , Humans , Muscle, Skeletal/growth & development , Muscle, Skeletal/immunologySubject(s)
Adipose Tissue/metabolism , Adiposity , Exercise Therapy , Myocardium/metabolism , Obesity, Abdominal/therapy , Receptors, Interleukin-6/metabolism , Adipose Tissue/physiopathology , Adult , Antibodies, Monoclonal, Humanized/administration & dosage , Double-Blind Method , Female , Humans , Male , Middle Aged , Obesity, Abdominal/diagnosis , Obesity, Abdominal/metabolism , Obesity, Abdominal/physiopathology , Receptors, Interleukin-6/antagonists & inhibitors , Signal Transduction , Time Factors , Treatment OutcomeABSTRACT
The objective of this study was to assess the insulin-independent effects of incretin hormones on glucose and glycerol metabolism and hemodynamics under euglycemic and hyperglycemic conditions. Young, healthy men (n=10) underwent three trials in a randomized, controlled, crossover study. Each trial consisted of a two-stage (euglycemia and hyperglycemia) pancreatic clamp (using somatostatin to prevent endogenous insulin secretion). Glucose and lipid metabolism was measured via infusion of stable glucose and glycerol isotopic tracers. Hemodynamic variables (femoral, brachial, and common carotid artery blood flow and flow-mediated dilation of the brachial artery) were also measured. The three trials differed as follows: 1) saline [control (CON)], 2) glucagon-like peptide (GLP-1, 0.5 pmol·kg(-1)·min(-1)), and 3) glucose-dependent insulinotropic polypeptide (GIP, 1.5 pmol·kg(-1)·min(-1)). No between-trial differences in glucose infusion rates (GIR) or glucose or glycerol kinetics were seen during euglycemia, whereas hyperglycemia resulted in increased GIR and glucose rate of disappearance during GLP-1 compared with CON and GIP (P<0.01 for all). However, when normalized to insulin levels, no differences between trials were seen for GIR or glucose rate of disappearance. Besides a higher femoral blood flow during hyperglycemia with GIP (vs. CON and GLP-1, P<0.001), no between-trial differences were seen for the hemodynamic variables. In conclusion, GLP-1 and GIP have no direct effect on whole body glucose metabolism or hemodynamics during euglycemia. On the contrary, during hyperglycemia, GIP increases femoral artery blood flow with no effect on glucose metabolism, whereas GLP-1 increases glucose disposal, potentially due to increased insulin levels.
Subject(s)
Glucose/metabolism , Glycerol/metabolism , Hemodynamics/drug effects , Incretins/pharmacology , Adolescent , Adult , Blood Glucose/drug effects , Blood Glucose/metabolism , Blood Pressure/drug effects , Carotid Artery, Common/drug effects , Carotid Artery, Common/physiology , Glucose Clamp Technique , Heart Rate/drug effects , Humans , Hyperglycemia/metabolism , Male , Pancreas/drug effects , Pancreas/metabolism , Regional Blood Flow/drug effects , Young AdultABSTRACT
AIMS/HYPOTHESIS: By use of a parallel and partly crossover randomised, controlled trial design we sought to elucidate the underlying mechanisms behind the advantageous effects of interval walking training (IWT) compared with continuous walking training (CWT) on glycaemic control in individuals with type 2 diabetes. We hypothesised that IWT, more than CWT, would improve insulin sensitivity including skeletal muscle insulin signalling, insulin secretion and disposition index (DI). METHODS: By simple randomisation (sequentially numbered, opaque sealed envelopes), eligible individuals (diagnosed with type 2 diabetes, no exogenous insulin treatment) were allocated to three groups: a control group (CON, n = 8), an IWT group (n = 12) and an energy expenditure-matched CWT group (n = 12). Training groups were prescribed free-living training, five sessions per week (60 min/session). A three-stage hyperglycaemic clamp, including glucose isotope tracers and skeletal muscle biopsies, was performed before and after a 4 month intervention in a hospitalised setting. No blinding was performed. RESULTS: The improved glycaemic control, which was only seen in the IWT group, was consistent with IWT-induced increases in insulin sensitivity index (49.8 ± 14.6%; p < 0.001), peripheral glucose disposal (14.5 ± 4.9%; p < 0.05) and DI (66.2 ± 21.8%; p < 0.001), with no changes in the CWT or CON group. Moreover, only IWT improved insulin signalling in skeletal muscle via increased insulin-stimulated phosphorylation of AS160 (29.0 ± 10.8%; p < 0.05). No changes were seen in insulin secretion during hyperglycaemia alone, hyperglycaemia + glucagon-like peptide 1 infusion or arginine injection. CONCLUSIONS/INTERPRETATION: IWT maintains insulin secretion and improves insulin sensitivity and DI, in contrast to energy expenditure-matched CWT. These results suggest that training with alternating intensity, and not just training volume and mean intensity, is a key determinant of changes in whole body glucose disposal in individuals with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials (NCT01234155).