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Szablewski L. Changes in Cells Associated with Insulin Resistance. Int J Mol Sci 2024; 25:2397. [PMID: 38397072 PMCID: PMC10889819 DOI: 10.3390/ijms25042397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 02/10/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024] Open
Abstract
Insulin is a polypeptide hormone synthesized and secreted by pancreatic β-cells. It plays an important role as a metabolic hormone. Insulin influences the metabolism of glucose, regulating plasma glucose levels and stimulating glucose storage in organs such as the liver, muscles and adipose tissue. It is involved in fat metabolism, increasing the storage of triglycerides and decreasing lipolysis. Ketone body metabolism also depends on insulin action, as insulin reduces ketone body concentrations and influences protein metabolism. It increases nitrogen retention, facilitates the transport of amino acids into cells and increases the synthesis of proteins. Insulin also inhibits protein breakdown and is involved in cellular growth and proliferation. On the other hand, defects in the intracellular signaling pathways of insulin may cause several disturbances in human metabolism, resulting in several chronic diseases. Insulin resistance, also known as impaired insulin sensitivity, is due to the decreased reaction of insulin signaling for glucose levels, seen when glucose use in response to an adequate concentration of insulin is impaired. Insulin resistance may cause, for example, increased plasma insulin levels. That state, called hyperinsulinemia, impairs metabolic processes and is observed in patients with type 2 diabetes mellitus and obesity. Hyperinsulinemia may increase the risk of initiation, progression and metastasis of several cancers and may cause poor cancer outcomes. Insulin resistance is a health problem worldwide; therefore, mechanisms of insulin resistance, causes and types of insulin resistance and strategies against insulin resistance are described in this review. Attention is also paid to factors that are associated with the development of insulin resistance, the main and characteristic symptoms of particular syndromes, plus other aspects of severe insulin resistance. This review mainly focuses on the description and analysis of changes in cells due to insulin resistance.
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Affiliation(s)
- Leszek Szablewski
- Chair and Department of General Biology and Parasitology, Medical University of Warsaw, Chałubińskiego Str. 5, 02-004 Warsaw, Poland
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2
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Insulin Metabolism in Polycystic Ovary Syndrome: Secretion, Signaling, and Clearance. Int J Mol Sci 2023; 24:ijms24043140. [PMID: 36834549 PMCID: PMC9962893 DOI: 10.3390/ijms24043140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/23/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age. Its heterogeneous clinical presentation is characterized by hyperandrogenemia, reproductive changes, polycystic ovary morphology, and insulin resistance (IR). The primary pathophysiological process in its multifactorial etiology has not yet been identified. However, the two most proposed core etiologies are the disruption of insulin metabolism and hyperandrogenemia, both of which begin to intertwine and propagate each other in the later stages of the disease. Insulin metabolism can be viewed as the interconnectedness of beta cell function, IR or insulin sensitivity, and insulin clearance. Previous studies of insulin metabolism in PCOS patients have yielded conflicting results, and literature reviews have focused mainly on the molecular mechanisms and clinical implications of IR. In this narrative review, we comprehensively explored the role of insulin secretion, clearance, and decreased sensitivity in target cells as a potential primary insult in PCOS pathogenesis, along with the molecular mechanism behind IR in PCOS.
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Liu J, Hu X. Impact of insulin therapy on outcomes of diabetic patients with heart failure: A systematic review and meta-analysis. Diab Vasc Dis Res 2022; 19:14791641221093175. [PMID: 35543342 PMCID: PMC9102182 DOI: 10.1177/14791641221093175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE To compare clinical outcomes in diabetic patients with heart failure managed by insulin with those managed by non-insulin (oral hypoglycemic agents and/or lifestyle modification) based therapy. METHODS PubMed and Scopus databases were searched for studies conducted on diabetic patients with heart failure. Studies were to compare outcomes of patients managed by insulin versus non-insulin therapies. RESULTS 15 studies were included. Compared to those who were managed using non-insulin therapy, insulin-treated patients had increased risk of all-cause mortality (RR 1.46, 95% CI: 1.14, 1.88) and cardiovascular specific mortality (RR 1.62, 95% CI: 1.33, 1.96). Those managed using insulin also had increased risk of hospitalization (RR 1.45, 95% CI: 1.09, 1.93) and readmission (RR 1.49, 95% CI: 1.32, 1.67). There was no additional risk for stroke (RR 1.07, 95% CI: 0.91, 1.27) or myocardial infarction (MI) (RR 1.10, 95% CI: 0.96, 1.27) between the two groups of patients. CONCLUSIONS Receipt of insulin among diabetic patients with heart failure was associated with an increased risk of mortality, hospitalization and readmission compared to management using oral hypoglycemic agents and/or lifestyle modification. Such patients should be closely monitored for any adverse events.
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Affiliation(s)
- Jingxing Liu
- Department of Emergency Intensive Care Medicine, Changxing People’s Hospital, Changxing County, Huzhou City, Zhejiang Province, China
| | - Xinhua Hu
- Department of Cardiology, Changxing People’s Hospital, Changxing County, Huzhou City, Zhejiang Province, China
- Xinhua Hu, Department of Cardiology, Changxing People’s Hospital, 66 Taihu Middle Road, Changxing County, Huzhou City, Zhejiang Province 313100, China.
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4
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Johnson JD. On the causal relationships between hyperinsulinaemia, insulin resistance, obesity and dysglycaemia in type 2 diabetes. Diabetologia 2021; 64:2138-2146. [PMID: 34296322 DOI: 10.1007/s00125-021-05505-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/23/2021] [Indexed: 12/19/2022]
Abstract
Hundreds of millions of people are affected by hyperinsulinaemia, insulin resistance, obesity and the dysglycaemia that mark a common progression from metabolic health to type 2 diabetes. Although the relative contribution of these features and the order in which they appear may differ between individuals, the common clustering and seemingly progressive nature of type 2 diabetes aetiology has guided research and clinical practice in this area for decades. At the same time, lively debate around the causal relationships between these features has continued, as new data from human trials and highly controlled animal studies are presented. This 'For debate' article was prompted by the review in Diabetologia by Esser, Utzschneider and Kahn ( https://doi.org/10.1007/s00125-020-05245-x ), with the purpose of reviewing established and emerging data that provide insight into the relative contributions of hyperinsulinaemia and impaired glucose-stimulated insulin secretion in progressive stages between health, obesity and diabetes. It is concluded that these beta cell defects are not mutually exclusive and that they are both important, but at different stages.
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Affiliation(s)
- James D Johnson
- Diabetes Research Group, Life Sciences Institute, Department of Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada.
- Institute for Personalized Therapeutic Nutrition, Vancouver, BC, Canada.
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Acierno C, Caturano A, Pafundi PC, Nevola R, Adinolfi LE, Sasso FC. Nonalcoholic fatty liver disease and type 2 diabetes: pathophysiological mechanisms shared between the two faces of the same coin. EXPLORATION OF MEDICINE 2020. [DOI: 10.37349/emed.2020.00019] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The pathophysiological mechanisms underlying the close relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are multiple, complex and only partially known. The purpose of this paper was to review the current knowledge of these mechanisms in a unified manner. Subjects with NAFLD and T2DM have established insulin resistance (IR), which exacerbates the two comorbidities. IR worsens NAFLD by increasing the accumulation of free fatty acids (FFAs) in the liver. This occurs due to an increase in the influx of FFAs from peripheral adipose tissue by the activation of hormone-sensitive lipase. In addition, there is de novo increased lipogenesis, a transcription factor, the sterols regulatory element-binding transcription factor 1c (SREBP-1c), which activates the expression of several genes strongly promotes lipogenesis by the liver and facilitate storage of triglycerides. Lipids accumulation in the liver induces a chronic stress in the endoplasmic reticulum of the hepatocytes. Genome-wide association studies have identified genetic variants associated with NAFLD severity, but unrelated to IR. In particular, the alteration of patatin-like phospholipase domain-containing protein 3 contributes to the susceptibility to NAFLD. Furthermore, the lipotoxicity of ceramides and diacylglycerol, well known in T2DM, triggers a chronic inflammatory process favoring the progression from hepatic steatosis to steatohepatitis. Reactive oxygen species produced by mitochondrial dysfunction trigger both liver inflammation and beta-cells damage, promoting the progression of both NAFLD and T2DM. The close association between NAFLD and T2DM is bidirectional, as T2DM may trigger both NAFLD onset and its progression, but NAFLD itself may contribute to the development of IR and T2DM. Future studies on the mechanisms will have to deepen the knowledge of the interaction between the two pathologies and should allow the identification of new therapeutic targets for the treatment of NAFLD, currently substantially absent.
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Affiliation(s)
- Carlo Acierno
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Italy
| | - Alfredo Caturano
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Italy
| | - Pia Clara Pafundi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Italy
| | - Riccardo Nevola
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Italy
| | - Luigi Elio Adinolfi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Italy
| | - Ferdinando Carlo Sasso
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, I-80138 Naples, Ital
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Velasco M, Ortiz-Huidobro RI, Larqué C, Sánchez-Zamora YI, Romo-Yáñez J, Hiriart M. Sexual dimorphism in insulin resistance in a metabolic syndrome rat model. Endocr Connect 2020; 9:890-902. [PMID: 33069157 PMCID: PMC7583132 DOI: 10.1530/ec-20-0288] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 08/14/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVE We assessed the sex-specific differences in the molecular mechanisms of insulin resistance in muscle and adipose tissue, in a MS rat model induced by a high sucrose diet. METHODS Male, female, and ovariectomized female Wistar rats were randomly distributed in control and high-sucrose diet (HSD) groups, supplemented for 24 weeks with 20% sucrose in the drinking water. At the end, we assessed parameters related to MS, analyzing the effects of the HSD on critical nodes of the insulin signaling pathway in muscle and adipose tissue. RESULTS At the end of the treatment, HSD groups of both sexes developed obesity, with a 15, 33 and 23% of body weight gain in male, female, and OVX groups respectively, compared with controls; mainly related to hypertrophy of peripancreatic and gonadal adipose tissue. They also developed hypertriglyceridemia, and liver steatosis, with the last being worse in the HSD females. Compared to the control groups, HSD rats had higher IL1B and TNFA levels and insulin resistance. HSD females were more intolerant to glucose than HSD males. Our observations suggest that insulin resistance mechanisms include an increase in phosphorylated AKT(S473) form in HSD male and female groups and a decrease in phosphorylated P70S6K1(T389) in the HSD male groups from peripancreatic adipose tissue. While in gonadal adipose tissue the phosphorylated form of AKT decreased in HSD females, but not in HSD males. Finally, HSD groups showed a reduction in p-AKT levels in gastrocnemius muscle. CONCLUSION A high-sucrose diet induces MS and insulin resistance with sex-associated differences and in a tissue-specific manner.
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Affiliation(s)
- Myrian Velasco
- Neuroscience Division, Department of Cognitive Neuroscience, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Correspondence should be addressed to M Velasco or M Hiriart: or
| | - Rosa Isela Ortiz-Huidobro
- Neuroscience Division, Department of Cognitive Neuroscience, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Carlos Larqué
- Department of Embryology and Genetics, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Yuriko Itzel Sánchez-Zamora
- Neuroscience Division, Department of Cognitive Neuroscience, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - José Romo-Yáñez
- Department of Gynecological and Perinatal Endocrinology, Instituto Nacional de Perinatología ‘Isidro Espinosa de los Reyes’, Mexico City, Mexico
| | - Marcia Hiriart
- Neuroscience Division, Department of Cognitive Neuroscience, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Correspondence should be addressed to M Velasco or M Hiriart: or
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Mehta A, Bhattacharya S, Estep J, Faiman C. Diabetes and Heart Failure: A Marriage of Inconvenience. Clin Geriatr Med 2020; 36:447-455. [PMID: 32586474 DOI: 10.1016/j.cger.2020.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Type 2 diabetes and congestive heart failure are growing public health problems and are expected to worsen in the next decade. There is an inarguable link between diabetes and heart failure but only recently has there been an effort to elucidate the underlying pathophysiologic connection resulting in diabetic cardiomyopathy. Traditionally, diabetes and heart failure have been treated as 2 distinct disease entities, but recent advances in individual therapies have shown remarkable concomitant improvements in both diabetes and cardiovascular outcomes. This article aims to review the key connections in the epidemiology and etiopathophysiology of type 2 diabetes and heart failure.
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Affiliation(s)
- Adi Mehta
- Endocrinology and Metabolism Institute, Cleveland Clinic, 9500 Euclid Avenue, F-20, Cleveland, OH 44195, USA.
| | - Sanjeeb Bhattacharya
- Section of Heart Failure and Cardiac Transplant Medicine, Cleveland Clinic, 9500 Euclid Avenue, J3-4, Cleveland, OH 44195, USA. https://twitter.com/SBhattacharyaMD
| | - Jerry Estep
- Section of Heart Failure and Cardiac Transplant Medicine, Cleveland Clinic, 9500 Euclid Avenue, J3-4, Cleveland, OH 44195, USA
| | - Charles Faiman
- Department of Endocrinology, Cleveland Clinic, 9500 Euclid Avenue, F-20, Cleveland, OH 44195, USA
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Currie CJ. Scientific independence and objectivity: many questions linger about treatment of type 2 diabetes, such as scientific study design, optimal glucose control and the safety of injecting exogenous insulin. Postgrad Med 2020; 132:667-675. [PMID: 32559126 DOI: 10.1080/00325481.2020.1784562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Whilst clinical guidelines exist for the treatment of people with type 2 diabetes, many underlying assumptions are still not qualified by convincing evidence. In this commentary, it is argued that fundamental issues still cloud clinical practice, such as biases in the design of clinical studies, the association between glucose control & clinical outcomes, and the safety of exposure to exogenous insulin and other glucose-lowering drugs. Relevant scientific evidence and alternative opinions about important issues continue to be largely ignored, and no effort has been made to resolve these questions. This may have had serious consequences, such as stifling innovation because there are no further benefits to be achieved in relation to glucose control.
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Affiliation(s)
- Craig J Currie
- Division of Population Medicine, School of Medicine, Cardiff University , Cardiff, UK.,Global Epidemiology, Pharmatelligence , Cardiff, UK
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Abstract
Patients with diabetes mellitus have >2× the risk for developing heart failure (HF; HF with reduced ejection fraction and HF with preserved ejection fraction). Cardiovascular outcomes, hospitalization, and prognosis are worse for patients with diabetes mellitus relative to those without. Beyond the structural and functional changes that characterize diabetic cardiomyopathy, a complex underlying, and interrelated pathophysiology exists. Despite the success of many commonly used antihyperglycemic therapies to lower hyperglycemia in type 2 diabetes mellitus the high prevalence of HF persists. This, therefore, raises the possibility that additional factors beyond glycemia might contribute to the increased HF risk in diabetes mellitus. This review summarizes the state of knowledge about the impact of existing antihyperglycemic therapies on HF and discusses potential mechanisms for beneficial or deleterious effects. Second, we review currently approved pharmacological therapies for HF and review evidence that addresses their efficacy in the context of diabetes mellitus. Dysregulation of many cellular mechanisms in multiple models of diabetic cardiomyopathy and in human hearts have been described. These include oxidative stress, inflammation, endoplasmic reticulum stress, aberrant insulin signaling, accumulation of advanced glycated end-products, altered autophagy, changes in myocardial substrate metabolism and mitochondrial bioenergetics, lipotoxicity, and altered signal transduction such as GRK (g-protein receptor kinase) signaling, renin angiotensin aldosterone signaling and β-2 adrenergic receptor signaling. These pathophysiological pathways might be amenable to pharmacological therapy to reduce the risk of HF in the context of type 2 diabetes mellitus. Successful targeting of these pathways could alter the prognosis and risk of HF beyond what is currently achieved using existing antihyperglycemic and HF therapeutics.
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Affiliation(s)
- Helena C Kenny
- From the Fraternal Order of Eagles Diabetes Research Center, and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City
| | - E Dale Abel
- From the Fraternal Order of Eagles Diabetes Research Center, and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City
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10
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Nolan CJ, Prentki M. Insulin resistance and insulin hypersecretion in the metabolic syndrome and type 2 diabetes: Time for a conceptual framework shift. Diab Vasc Dis Res 2019; 16:118-127. [PMID: 30770030 DOI: 10.1177/1479164119827611] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
While few dispute the existence of the metabolic syndrome as a clustering of factors indicative of poor metabolic health, its utility above that of its individual components in the clinical care of individual patients is questioned. This is likely a consequence of the failure of clinicians and scientists to agree on a unifying mechanism to explain the metabolic syndrome. Insulin resistance has most commonly been proposed for this role and is generally considered to be a root causative factor for not only metabolic syndrome but also for its associated conditions of non-alcoholic fatty liver disease (NAFLD), polycystic ovary syndrome (PCOS), obesity-related type 2 diabetes (T2D) and atherosclerotic cardiovascular disease (ASCVD). An alternative view, for which evidence is mounting, is that hyper-responsiveness of islet β-cells to a hostile environment, such as westernised lifestyle, is primary and that the resulting hyperinsulinaemia drives the other components of the metabolic syndrome. Importantly, within this new conceptual framework, insulin resistance, while always a biomarker and state of poor metabolic health, is not considered to be harmful, but a protective adaptive response of critical tissues including the myocardium against insulin-induced metabolic stress. This major shift in how metabolic syndrome can be considered puts insulin hypersecretion into position as the unifying mechanism. If shown to be correct, this new conceptual framework has major implications for the future prevention and management of the metabolic syndrome, including its associated conditions of NAFLD, PCOS, obesity-related T2D and ASCVD.
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Affiliation(s)
- Christopher J Nolan
- 1 Department of Endocrinology, The Canberra Hospital, Garran, ACT, Australia
- 2 Australian National University Medical School and John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Marc Prentki
- 3 CRCHUM and Montreal Diabetes Research Center, University of Montreal, Montreal, QC, Canada
- 4 Department of Nutrition and Department of Biochemistry and Molecular Medicine, University of Montreal, Montreal, QC, Canada
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Levelt E, Gulsin G, Neubauer S, McCann GP. MECHANISMS IN ENDOCRINOLOGY: Diabetic cardiomyopathy: pathophysiology and potential metabolic interventions state of the art review. Eur J Endocrinol 2018; 178:R127-R139. [PMID: 29440374 PMCID: PMC5863473 DOI: 10.1530/eje-17-0724] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 02/12/2018] [Indexed: 12/22/2022]
Abstract
Heart failure is a major cause of morbidity and mortality in type 2 diabetes. Type 2 diabetes contributes to the development of heart failure through a variety of mechanisms, including disease-specific myocardial structural, functional and metabolic changes. This review will focus on the contemporary contributions of state of the art non-invasive technologies to our understanding of diabetic cardiomyopathy, including data on cardiac disease phenotype, cardiac energy metabolism and energetic deficiency, ectopic and visceral adiposity, diabetic liver disease, metabolic modulation strategies and cardiovascular outcomes with new classes of glucose-lowering therapies.
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Affiliation(s)
- Eylem Levelt
- British Heart Foundation Cardiovascular Research CentreUniversity of Leicester, Glenfield Hospital, Leicester, UK
- (E Levelt is now at Multidisciplinary Cardiovascular Research Centre and Biomedical Imaging Science DepartmentLeeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK)
- Correspondenceshould be addressed to E Levelt;
| | - Gaurav Gulsin
- British Heart Foundation Cardiovascular Research CentreUniversity of Leicester, Glenfield Hospital, Leicester, UK
| | - Stefan Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance ResearchUniversity of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Gerry P McCann
- British Heart Foundation Cardiovascular Research CentreUniversity of Leicester, Glenfield Hospital, Leicester, UK
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Herman ME, O'Keefe JH, Bell DSH, Schwartz SS. Insulin Therapy Increases Cardiovascular Risk in Type 2 Diabetes. Prog Cardiovasc Dis 2017; 60:422-434. [PMID: 28958751 DOI: 10.1016/j.pcad.2017.09.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 09/20/2017] [Indexed: 12/11/2022]
Abstract
Insulin therapy increased cardiovascular (CV) risk and mortality among type 2 diabetes (T2D) patients in several recently reported clinical outcomes trials. To assess whether this association is causative or coincidental, PubMed searches were used to query the effects of insulin therapy for T2D on CV health and longevity from large-scale outcomes trials, meta-analyses, and patient registry studies, as well as basic research on insulin's direct and pleiotropic actions. Although several old studies provided conflicting results, the majority of large observational studies show strong dose-dependent associations for injected insulin with increased CV risk and worsened mortality. Insulin clearly causes weight gain, recurrent hypoglycemia, and, other potential adverse effects, including iatrogenic hyperinsulinemia. This over-insulinization with use of injected insulin predisposes to inflammation, atherosclerosis, hypertension, dyslipidemia, heart failure (HF), and arrhythmias. These associations support the findings of large-scale evaluations that strongly suggest that insulin therapy has a poorer short- and long-term safety profile than that found to many other anti-T2D therapies. The potential adverse effects of insulin therapy should be weighed against proven CV benefits noted for select other therapies for T2D as reported in recent large randomized controlled trials.
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Affiliation(s)
- Mary E Herman
- Montclair State University, New Jersey, United States; Social Alchemy Ltd. Building Global Research Competency, United States
| | - James H O'Keefe
- University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States; Saint Luke's Mid America Heart Institute, United States.
| | | | - Stanley S Schwartz
- Main Line Health System, Wynnewood, PA, United States; University of Pennsylvania, Philadelphia, PA, United States
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Schwartz SS, Epstein S, Corkey BE, Grant SFA, Gavin Iii JR, Aguilar RB, Herman ME. A Unified Pathophysiological Construct of Diabetes and its Complications. Trends Endocrinol Metab 2017. [PMID: 28629897 DOI: 10.1016/j.tem.2017.05.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Advances in understanding diabetes mellitus (DM) through basic and clinical research have helped clarify and reunify a disease state fragmented into numerous etiologies and subtypes. It is now understood that a common pathophysiology drives the diabetic state throughout its natural history and across its varied clinical presentations, a pathophysiology involving metabolic insults, oxidative damage, and vicious cycles that aggravate and intensify organ dysfunction and damage. This new understanding of the disease requires that we revisit existing diagnostics and treatment approaches, which were built upon outmoded assumptions. 'The Common Pathophysiologic Origins of Diabetes Mellitus and its Complications Construct' is presented as a more accurate, foundational, and translatable construct of DM that helps make sense of the hitherto ambiguous findings of long-term outcome studies.
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Affiliation(s)
- Stanley S Schwartz
- Main Line Health System, Wynnewood, PA, USA; University of Pennsylvania, Philadelphia, PA, USA.
| | - Solomon Epstein
- Medicine, Endocrinology, Diabetes and Bone Disease, Mount Sinai Hospital, New York, NY, USA
| | - Barbara E Corkey
- Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Struan F A Grant
- Division of Human Genetics and Center for Applied Genomics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Divisions of Human Genetics and Endocrinology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Mary E Herman
- Montclair State University, Upper Montclair, NJ, USA; Social Alchemy Ltd., Building Global Research Competency, Lynchburg, VA, USA
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14
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Mugabo Y, Zhao S, Lamontagne J, Al-Mass A, Peyot ML, Corkey BE, Joly E, Madiraju SRM, Prentki M. Metabolic fate of glucose and candidate signaling and excess-fuel detoxification pathways in pancreatic β-cells. J Biol Chem 2017; 292:7407-7422. [PMID: 28280244 DOI: 10.1074/jbc.m116.763060] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 03/06/2017] [Indexed: 12/28/2022] Open
Abstract
Glucose metabolism promotes insulin secretion in β-cells via metabolic coupling factors that are incompletely defined. Moreover, chronically elevated glucose causes β-cell dysfunction, but little is known about how cells handle excess fuels to avoid toxicity. Here we sought to determine which among the candidate pathways and coupling factors best correlates with glucose-stimulated insulin secretion (GSIS), define the fate of glucose in the β-cell, and identify pathways possibly involved in excess-fuel detoxification. We exposed isolated rat islets for 1 h to increasing glucose concentrations and measured various pathways and metabolites. Glucose oxidation, oxygen consumption, and ATP production correlated well with GSIS and saturated at 16 mm glucose. However, glucose utilization, glycerol release, triglyceride and glycogen contents, free fatty acid (FFA) content and release, and cholesterol and cholesterol esters increased linearly up to 25 mm glucose. Besides being oxidized, glucose was mainly metabolized via glycerol production and release and lipid synthesis (particularly FFA, triglycerides, and cholesterol), whereas glycogen production was comparatively low. Using targeted metabolomics in INS-1(832/13) cells, we found that several metabolites correlated well with GSIS, in particular some Krebs cycle intermediates, malonyl-CoA, and lower ADP levels. Glucose dose-dependently increased the dihydroxyacetone phosphate/glycerol 3-phosphate ratio in INS-1(832/13) cells, indicating a more oxidized state of NAD in the cytosol upon glucose stimulation. Overall, the data support a role for accelerated oxidative mitochondrial metabolism, anaplerosis, and malonyl-CoA/lipid signaling in β-cell metabolic signaling and suggest that a decrease in ADP levels is important in GSIS. The results also suggest that excess-fuel detoxification pathways in β-cells possibly comprise glycerol and FFA formation and release extracellularly and the diversion of glucose carbons to triglycerides and cholesterol esters.
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Affiliation(s)
- Yves Mugabo
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Nutrition, Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montréal, Montreal, Québec H3C 3J7, Canada, and
| | - Shangang Zhao
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Medicine and Human Genetics, McGill University, Montreal, Québec H3A 1B1, Canada
| | - Julien Lamontagne
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Anfal Al-Mass
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Medicine and Human Genetics, McGill University, Montreal, Québec H3A 1B1, Canada
| | - Marie-Line Peyot
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Barbara E Corkey
- Department of Medicine, Obesity Research Center, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Erik Joly
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - S R Murthy Madiraju
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Marc Prentki
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada, .,Departments of Nutrition, Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montréal, Montreal, Québec H3C 3J7, Canada, and
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15
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Templeman NM, Skovsø S, Page MM, Lim GE, Johnson JD. A causal role for hyperinsulinemia in obesity. J Endocrinol 2017; 232:R173-R183. [PMID: 28052999 DOI: 10.1530/joe-16-0449] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 01/03/2017] [Indexed: 12/13/2022]
Abstract
Insulin modulates the biochemical pathways controlling lipid uptake, lipolysis and lipogenesis at multiple levels. Elevated insulin levels are associated with obesity, and conversely, dietary and pharmacological manipulations that reduce insulin have occasionally been reported to cause weight loss. However, the causal role of insulin hypersecretion in the development of mammalian obesity remained controversial in the absence of direct loss-of-function experiments. Here, we discuss theoretical considerations around the causal role of excess insulin for obesity, as well as recent studies employing mice that are genetically incapable of the rapid and sustained hyperinsulinemia that normally accompanies a high-fat diet. We also discuss new evidence demonstrating that modest reductions in circulating insulin prevent weight gain, with sustained effects that can persist after insulin levels normalize. Importantly, evidence from long-term studies reveals that a modest reduction in circulating insulin is not associated with impaired glucose homeostasis, meaning that body weight and lipid homeostasis are actually more sensitive to small changes in circulating insulin than glucose homeostasis in these models. Collectively, the evidence from new studies on genetic loss-of-function models forces a re-evaluation of current paradigms related to obesity, insulin resistance and diabetes. The potential for translation of these findings to humans is briefly discussed.
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Affiliation(s)
- Nicole M Templeman
- Department of Cellular and Physiological SciencesDiabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Søs Skovsø
- Department of Cellular and Physiological SciencesDiabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Melissa M Page
- Department of Cellular and Physiological SciencesDiabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gareth E Lim
- Department of Cellular and Physiological SciencesDiabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - James D Johnson
- Department of Cellular and Physiological SciencesDiabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Institute for Personalized Therapeutic NutritionVancouver, British Columbia, Canada
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16
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Levelt E, Pavlides M, Banerjee R, Mahmod M, Kelly C, Sellwood J, Ariga R, Thomas S, Francis J, Rodgers C, Clarke W, Sabharwal N, Antoniades C, Schneider J, Robson M, Clarke K, Karamitsos T, Rider O, Neubauer S. Ectopic and Visceral Fat Deposition in Lean and Obese Patients With Type 2 Diabetes. J Am Coll Cardiol 2016; 68:53-63. [PMID: 27364051 PMCID: PMC4925621 DOI: 10.1016/j.jacc.2016.03.597] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 03/27/2016] [Accepted: 03/29/2016] [Indexed: 01/14/2023]
Abstract
BACKGROUND Type 2 diabetes (T2D) and obesity are associated with nonalcoholic fatty liver disease, cardiomyopathy, and cardiovascular mortality. Both show stronger links between ectopic and visceral fat deposition, and an increased cardiometabolic risk compared with subcutaneous fat. OBJECTIVES This study investigated whether lean patients (Ln) with T2D exhibit increased ectopic and visceral fat deposition and whether these are linked to cardiac and hepatic changes. METHODS Twenty-seven obese patients (Ob) with T2D, 15 Ln-T2D, and 12 normal-weight control subjects were studied. Subjects underwent cardiac computed tomography, cardiac magnetic resonance imaging (MRI), proton and phosphorus MR spectroscopy, and multiparametric liver MR, including hepatic proton MRS, T1- and T2*-mapping yielding "iron-corrected T1" [cT1]. RESULTS Diabetes, with or without obesity, was associated with increased myocardial triglyceride content (p = 0.01), increased hepatic triglyceride content (p = 0.04), and impaired myocardial energetics (p = 0.04). Although cardiac structural changes, steatosis, and energetics were similar between the T2D groups, epicardial fat (p = 0.04), hepatic triglyceride (p = 0.01), and insulin resistance (p = 0.03) were higher in Ob-T2D. Epicardial fat, hepatic triglyceride, and insulin resistance correlated negatively with systolic strain and diastolic strain rates, which were only significantly impaired in Ob-T2D (p < 0.001 and p = 0.006, respectively). Fibroinflammatory liver disease (elevated cT1) was only evident in Ob-T2D patients. cT1 correlated with hepatic and epicardial fat (p < 0.001 and p = 0.01, respectively). CONCLUSIONS Irrespective of body mass index, diabetes is related to significant abnormalities in cardiac structure, energetics, and cardiac and hepatic steatosis. Obese patients with T2D show a greater propensity for ectopic and visceral fat deposition.
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Affiliation(s)
- Eylem Levelt
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom; Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Michael Pavlides
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom; Translational Gastroenterology Unit, University of Oxford, Oxford, United Kingdom
| | | | - Masliza Mahmod
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | | | - Joanna Sellwood
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Rina Ariga
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Sheena Thomas
- Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
| | - Jane Francis
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Christopher Rodgers
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - William Clarke
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Nikant Sabharwal
- Cardiology Department, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | | | - Jurgen Schneider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Matthew Robson
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Theodoros Karamitsos
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Oliver Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom
| | - Stefan Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford, United Kingdom; Perspectum Diagnostics Ltd., Oxford, United Kingdom.
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17
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Schwartz SS, Jellinger PS, Herman ME. Obviating much of the need for insulin therapy in type 2 diabetes mellitus: A re-assessment of insulin therapy’s safety profile. Postgrad Med 2016; 128:609-19. [DOI: 10.1080/00325481.2016.1191955] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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18
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Taegtmeyer H, Beauloye C, Harmancey R, Hue L. Comment on Nolan et al. Insulin Resistance as a Physiological Defense Against Metabolic Stress: Implications for the Management of Subsets of Type 2 Diabetes. Diabetes 2015;64:673-686. Diabetes 2015; 64:e37. [PMID: 26405279 PMCID: PMC7519471 DOI: 10.2337/db15-0655] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Heinrich Taegtmeyer
- Division of Cardiovascular Medicine, Department of Internal Medicine, The University of Texas Medical School at Houston, Houston, TX
| | - Christophe Beauloye
- Pôle de Recherche Cardiovasculaire, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Romain Harmancey
- Department of Physiology and Biophysics, The University of Mississippi Medical Center, Jackson, MS
| | - Louis Hue
- Protein Phosphorylation Unit, de Duve Institute, Université catholique de Louvain, Brussels, Belgium
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19
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Nolan CJ, Ruderman NB, Kahn SE, Pedersen O, Prentki M. Response to Comments on Nolan et al. Insulin Resistance as a Physiological Defense Against Metabolic Stress: Implications for the Management of Subsets of Type 2 Diabetes. Diabetes 2015;64:673-686. Diabetes 2015; 64:e38-9. [PMID: 26405280 DOI: 10.2337/dbi15-0002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Christopher J Nolan
- Department of Endocrinology at Canberra Hospital and the Australian National University Medical School, Canberra, Australia
| | - Neil B Ruderman
- Diabetes Research Unit, Boston University Medical Center, Boston, MA
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, VA Puget Sound Health Care System, and University of Washington, Seattle, WA
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marc Prentki
- CRCHUM and Montreal Diabetes Research Center and Departments of Nutrition and Biochemistry and Molecular Medicine, University of Montreal, Quebec, Canada
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20
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Valentine WJ, Curtis BH, Pollock RF, Van Brunt K, Paczkowski R, Brändle M, Boye KS, Kendall DM. Is the current standard of care leading to cost-effective outcomes for patients with type 2 diabetes requiring insulin? A long-term health economic analysis for the UK. Diabetes Res Clin Pract 2015; 109:95-103. [PMID: 25989713 DOI: 10.1016/j.diabres.2015.04.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 03/14/2015] [Accepted: 04/15/2015] [Indexed: 12/18/2022]
Abstract
AIMS The aim of the analysis was to investigate whether insulin intensification, based on the use of intensive insulin regimens as recommended by the current standard of care in routine clinical practice, would be cost-effective for patients with type 2 diabetes in the UK. METHODS Clinical data were derived from a retrospective analysis of 3185 patients with type 2 diabetes on basal insulin in The Health Improvement Network (THIN) general practice database. In total, 48% (614 patients) intensified insulin therapy, defined by adding bolus or premix insulin to a basal regimen, which was associated with a reduction in HbA1c and an increase in body mass index. Projections of clinical outcomes and costs (2011 GBP) over patients' lifetimes were made using a recently validated type 2 diabetes model. RESULTS Immediate insulin intensification was associated with improvements in life expectancy, quality-adjusted life expectancy and time to onset of complications versus no intensification or delaying intensification by 2, 4, 6, or 8 years. Direct costs were higher with the insulin intensification strategy (due to the acquisition costs of insulin). Incremental cost-effectiveness ratios for insulin intensification were GBP 32,560, GBP 35,187, GBP 40,006, GBP 48,187 and GBP 55,431 per QALY gained versus delaying intensification 2, 4, 6 and 8 years, and no intensification, respectively. CONCLUSIONS Although associated with improved clinical outcomes, insulin intensification as practiced in the UK has a relatively high cost per QALY and may not lead to cost-effective outcomes for patients with type 2 diabetes as currently defined by UK cost-effectiveness thresholds.
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Affiliation(s)
- W J Valentine
- Ossian Health Economics and Communications, Basel, Switzerland.
| | - B H Curtis
- Eli Lilly and Company, Indianapolis, IN, USA
| | - R F Pollock
- Ossian Health Economics and Communications, Basel, Switzerland
| | - K Van Brunt
- Lilly Research Center, Windlesham, Surrey, UK
| | | | - M Brändle
- Division of Endocrinology and Diabetes, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - K S Boye
- Eli Lilly and Company, Indianapolis, IN, USA
| | - D M Kendall
- Eli Lilly and Company, Indianapolis, IN, USA
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21
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Nolan CJ, Ruderman NB, Kahn SE, Pedersen O, Prentki M. Insulin resistance as a physiological defense against metabolic stress: implications for the management of subsets of type 2 diabetes. Diabetes 2015; 64:673-86. [PMID: 25713189 PMCID: PMC4338588 DOI: 10.2337/db14-0694] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stratifying the management of type 2 diabetes (T2D) has to take into account marked variability in patient phenotype due to heterogeneity in its pathophysiology, different stages of the disease process, and multiple other patient factors including comorbidities. The focus here is on the very challenging subgroup of patients with T2D who are overweight or obese with insulin resistance (IR) and the most refractory hyperglycemia due to an inability to change lifestyle to reverse positive energy balance. For this subgroup of patients with T2D, we question the dogma that IR is primarily harmful to the body and should be counteracted at any cost. Instead we propose that IR, particularly in this high-risk subgroup, is a defense mechanism that protects critical tissues of the cardiovascular system from nutrient-induced injury. Overriding IR in an effort to lower plasma glucose levels, particularly with intensive insulin therapy, could therefore be harmful. Treatments that nutrient off-load to lower glucose are more likely to be beneficial. The concepts of "IR as an adaptive defense mechanism" and "insulin-induced metabolic stress" may provide explanation for some of the unexpected outcomes of recent major clinical trials in T2D. Potential molecular mechanisms underlying these concepts; their clinical implications for stratification of T2D management, particularly in overweight and obese patients with difficult glycemic control; and future research requirements are discussed.
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Affiliation(s)
- Christopher J Nolan
- Department of Endocrinology at Canberra Hospital and the Australian National University Medical School, Canberra, Australia
| | - Neil B Ruderman
- Diabetes Research Unit, Boston University Medical Center, Boston, MA
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, VA Puget Sound Health Care System, and University of Washington, Seattle, WA
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marc Prentki
- CRCHUM and Montreal Diabetes Research Center and Departments of Nutrition and Biochemistry and Molecular Medicine, University of Montreal, Quebec, Canada
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22
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Del Prato S. Fixed-ratio combination of basal insulin and GLP-1 receptor agonist: is two better than one? Lancet Diabetes Endocrinol 2014; 2:856-8. [PMID: 25190524 DOI: 10.1016/s2213-8587(14)70185-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Stefano Del Prato
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa, 56124 Pisa, Italy.
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23
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Triggle CR, Ding H. Cardiovascular impact of drugs used in the treatment of diabetes. Ther Adv Chronic Dis 2014; 5:245-68. [PMID: 25364492 PMCID: PMC4205571 DOI: 10.1177/2040622314546125] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The International Diabetes Federation predicts that by 2035 10% of the population of the world will have been diagnosed with diabetes, raising serious concerns over the resulting elevated morbidity and mortality as well as the impact on health care budgets. It is also well recognized that cardiovascular disease is the primary cause of the high morbidity and mortality associated with diabetes, raising the concern that appropriate drug therapy should not only correct metabolic dysfunction, but also protect the cardiovascular system from the effects of, in particular, the epigenetic changes that result from hyperglycaemia. A number of new classes of drugs for the treatment of diabetes have been introduced in the past decade, providing the opportunity to optimize treatment; however, comparative information of the cardiovascular benefits, or risks, of the newer drugs versus older therapies such as metformin is variable. This review, in addition to summarizing the cellular basis for the therapeutic action of these drugs, addresses the evidence for their cardiovascular benefits and risks. A particular focus is provided on metformin as it is the first choice drug for most patients with type 2 diabetes.
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Affiliation(s)
- Chris R Triggle
- Departments of Pharmacology and Medical Education, Weill Cornell Medical College in Qatar, PO Box 24144, Education City, Doha, Qatar
| | - Hong Ding
- Departments of Pharmacology and Medical Education, Weill Cornell Medical College in Qatar, Education City, Doha, Qatar
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24
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Currie CJ, Holden SE. Optimizing clinical outcomes resulting from glucose-lowering therapies in type 2 diabetes: increased confidence about the DPP-4 inhibitors and continued concerns regarding sulphonylureas and exogenous insulin. Diabetes Obes Metab 2014; 16:881-4. [PMID: 25040702 DOI: 10.1111/dom.12349] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 06/27/2014] [Accepted: 06/30/2014] [Indexed: 12/22/2022]
Affiliation(s)
- C J Currie
- Cochrane Institute of Public Health & Primary Care, School of Medicine, Cardiff University, Cardiff, UK
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25
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Depczynski B, Poynten AM, Fazekas M. Triggers to offering bariatric surgery in the management of type 2 diabetes. Obes Res Clin Pract 2014; 8:e421-5. [PMID: 24925516 DOI: 10.1016/j.orcp.2014.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/24/2014] [Accepted: 03/29/2014] [Indexed: 01/06/2023]
Abstract
It is unclear how current guidelines suggesting bariatric surgery as a therapeutic option for management of obesity complicated by type 2 diabetes mellitus are utilised in clinical practice. Of 609 patients with T2DM assessed in this study, 147 had a BMI ≥ 35 kg/m2; and of these 147, patients where bariatric surgery had been discussed as compared to those where it had not been discussed, had a higher BMI (44.4 ± 6.8 kg/m2 versus 40.3 ± 5.2 kg/m2, p < 0.005). Diabetes related factors did not differ between the two groups.
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26
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Abstract
Diabetes mellitus has been increasing in prevalence and imposes serious economic burdens on both the developed as well as the developing world. Understanding pathobiological underpinning of chronic progressive disease like diabetes is an imperative that we cannot escape. For several decades now, the focus has remained on a two hit theory which begins with insulin resistance and is followed thereafter by the β cell failure. Therapies have revolved around this concept with only limited success. Reorientation in our understanding of "islet pathology" should help rethink strategies that would yield better dividends in terms of effective therapy. Role of Glucagon needs to be revisited and incorporated to create treatment regimens addressing the concept of bi-hormonal defect rather than remaining stuck in standalone "insulinopathy." This brief review hopes to initiate/continue that dialogue.
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Affiliation(s)
- Romesh Khardori
- Department of Medicine, Division of Endocrinology and Metabolism, Strelitz Center for Diabetes, Endocrine and Metabolic Disorders, Eastern Virginia Medical School, Norfolk, VA 23510, USA
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27
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Ruderman NB, Carling D, Prentki M, Cacicedo JM. AMPK, insulin resistance, and the metabolic syndrome. J Clin Invest 2013; 123:2764-72. [PMID: 23863634 DOI: 10.1172/jci67227] [Citation(s) in RCA: 604] [Impact Index Per Article: 54.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Insulin resistance (IR) and hyperinsulinemia are hallmarks of the metabolic syndrome, as are central adiposity, dyslipidemia, and a predisposition to type 2 diabetes, atherosclerotic cardiovascular disease, hypertension, and certain cancers. Regular exercise and calorie restriction have long been known to increase insulin sensitivity and decrease the prevalence of these disorders. The subsequent identification of AMP-activated protein kinase (AMPK) and its activation by exercise and fuel deprivation have led to studies of the effects of AMPK on both IR and metabolic syndrome-related diseases. In this review, we evaluate this body of literature, with special emphasis on the hypothesis that dysregulation of AMPK is both a pathogenic factor for these disorders in humans and a target for their prevention and therapy.
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Affiliation(s)
- Neil B Ruderman
- Diabetes and Metabolism Research Unit, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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