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Peters A, Sprengell M, Kubera B. The principle of 'brain energy on demand' and its predictive power for stress, sleep, stroke, obesity and diabetes. Neurosci Biobehav Rev 2022; 141:104847. [PMID: 36067964 DOI: 10.1016/j.neubiorev.2022.104847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 08/10/2022] [Accepted: 08/26/2022] [Indexed: 12/01/2022]
Abstract
Does the brain actively draw energy from the body when needed? There are different schools of thought regarding energy metabolism. In this study, the various theoretical models are classified into one of two categories: (1) conceptualizations of the brain as being purely passively supplied, which we call 'P-models,' and (2) models understanding the brain as not only passively receiving energy but also actively procuring energy for itself on demand, which we call 'A-models.' One prominent example of such theories making use of an A-model is the selfish-brain theory. The ability to make predictions was compared between the A- and P-models. A-models were able to predict and coherently explain all data examined, which included stress, sleep, caloric restriction, stroke, type-1-diabetes mellitus, obesity, and type-2-diabetes, whereas the predictions of P-models failed in most cases. The strength of the evidence supporting A-models is based on the coherence of accurate predictions across a spectrum of metabolic states. The theory test conducted here speaks to a brain that pulls its energy from the body on-demand.
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Affiliation(s)
- Achim Peters
- Medical Clinic 1, Center of Brain, Behavior and Metabolism, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany.
| | - Marie Sprengell
- Medical Clinic 1, Center of Brain, Behavior and Metabolism, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
| | - Britta Kubera
- Medical Clinic 1, Center of Brain, Behavior and Metabolism, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
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Bidlingmaier M, Valcour A, Schilbach K, Kuehnle T, Diederich S, Rogge T, Cavalier E, Katayev A. Differences in the distribution of insulin-like growth-factor-I (IGF-I) concentrations between European and US populations. J Endocr Soc 2022; 6:bvac081. [PMID: 35673402 PMCID: PMC9165432 DOI: 10.1210/jendso/bvac081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Indexed: 11/19/2022] Open
Abstract
Abstract
Context
Method-specific reference intervals (RIs) determine utility of IGF-I as a biomarker in growth hormone-related diseases. Differences between populations might affect applicability of RIs.
Objective
To compare population-specific RIs derived from IGF-I routine testing in laboratories in the US and Europe using the same assay.
Design and setting
Uncensored routine IGF-I testing results generated over 5 years in four accredited laboratories (US, n=778,173 males/710,752 females; Europe, n=23,220 males/40,183 females).
Main outcome measures
Construction of RIs by indirect statistical methods designed to utilize routine testing data (modified Hoffmann approach). Comparison to published RIs, between the US and Europe, and between regions in the US with lower and higher mean body mass indexes (BMIs).
Results
Lower limits (LLs) of RIs calculated from all routine data sets do not differ from the published LLs. The same is true for Upper limits (ULs) calculated from European routine data. ULs derived from US routine data are significantly higher (children (10–18 years [mean, %]: boys +149.3 ng/mL [+34.6%]; girls +94.9 ng/mL [+19.8%]); adults (19–95 years: males +45 ng/mL [+20.3%]; females +29.7 ng/mL [+13.8%])). Average IGF-I is higher in samples from Colorado (lower mean BMI) compared with Alabama (p <0.0001), although the difference is smaller than between each of them and Europe.
Conclusions
We provide evidence that in large datasets from the same population, direct sampling and the indirect Hoffmann approach provide comparable RIs. While LLs are comparable between Europe and the US, the UL is significantly higher in the US. We suggest use of adapted RIs for the US.
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Affiliation(s)
- Martin Bidlingmaier
- Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Andre Valcour
- Laboratory Corporation of America Holdings, North Carolina, USA
| | - Katharina Schilbach
- Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Tim Kuehnle
- Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | | | | | | | - Alex Katayev
- Laboratory Corporation of America Holdings, North Carolina, USA
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Network Pharmacology Study to Reveal the Potentiality of a Methanol Extract of Caesalpinia sappan L. Wood against Type-2 Diabetes Mellitus. Life (Basel) 2022; 12:life12020277. [PMID: 35207564 PMCID: PMC8880704 DOI: 10.3390/life12020277] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 12/22/2022] Open
Abstract
Caesalpinia sappan L. (CS) is widely used to treat diabetic complications in south-east Asia, specifically in traditional Chinese medicine. This study intends to explain the molecular mechanism of how chemical constituents of CS interrelate with different signaling pathways and receptors involved in T2DM. GC-MS was employed to identify the chemical compounds from the methanol extract of CS wood (MECSW). Lipinski’s rule of five was applied, and 33 bioactive constituents have been screened from the CS extract. After that, 124 common targets and 26 compounds associated with T2DM were identified by mining several public databases. Protein–protein interactions and compound-target network were constructed using the STRING database and Cytoscape tool. Protein–protein interactions were identified in 121 interconnected nodes active in T2DM and peroxisome proliferator-activated receptor gamma (PPARG) as key target receptors. Furthermore, pathway compound target (PCT) analysis using the merger algorithm plugin of Cytoscape revealed 121 nodes from common T2DM targets, 33 nodes from MECSW compounds and 9 nodes of the KEGG pathway. Moreover, network topology analysis determined “Fisetin tetramethyl ether” as the key chemical compound. The DAVID online tool determined seven signaling receptors, among which PPARG was found most significant in T2DM progression. Gene ontology and KEGG pathway analysis implied the involvement of nine pathways, and the peroxisome proliferator-activated receptor (PPAR) pathway was selected as the hub signaling pathway. Finally, molecular docking and quantum chemistry analysis confirmed the strong binding affinity and reactive chemical nature of fisetin tetramethyl ether with target receptors exceeding that of the conventional drug (metformin), PPARs agonist (rosiglitazone) and co-crystallized ligands, indicating that fisetin could be a potential drug of choice in T2DM management. This study depicts the interrelationship of the bioactive compounds of MECSW with the T2DM-associated signaling pathways and target receptors. It also proposes a more pharmaceutically effective substance, fisetin tetramethyl ether, over the standard drug that activates PPARG protein in the PPAR signaling pathway of T2DM.
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Gaddas M. Le dosage de l’Insulin-Like Growth Factor-1 : les difficultés de la détermination sérique et de l’interprétation des résultats. NUTR CLIN METAB 2022. [DOI: 10.1016/j.nupar.2021.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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5
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Type 2 Diabetes Mellitus and Cancer: Epidemiology, Physiopathology and Prevention. Biomedicines 2021; 9:biomedicines9101429. [PMID: 34680546 PMCID: PMC8533606 DOI: 10.3390/biomedicines9101429] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 09/29/2021] [Accepted: 10/05/2021] [Indexed: 01/01/2023] Open
Abstract
Individuals with type 2 diabetes mellitus are at greater risk of developing cancer and of dying from it. Both diseases are age-related, contributing to the impact of population aging on the long-term sustainability of health care systems in European Union countries. The purpose of this narrative review was to describe, from epidemiological, pathophysiological and preventive perspectives, the links between type 2 diabetes mellitus and the most prevalent cancers in these patients. Multiple metabolic abnormalities that may occur in type 2 diabetes mellitus, particularly obesity, could explain the increased cancer risk. In addition, the effectiveness of drugs commonly used to treat type 2 diabetes mellitus (e.g., metformin and thiazolidinediones) has been broadly evaluated in cancer prevention. Thus, a better understanding of the links between type 2 diabetes mellitus and cancer will help to identify the contributing factors and the pathophysiological pathways and to design personalized preventive strategies. The final goal is to facilitate healthy aging and the prevention of cancer and other diseases related with type 2 diabetes mellitus, which are among the main sources of disability and death in the European Union and worldwide.
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Suh S, Kim KW. Diabetes and Cancer: Cancer Should Be Screened in Routine Diabetes Assessment. Diabetes Metab J 2019; 43:733-743. [PMID: 31902143 PMCID: PMC6943263 DOI: 10.4093/dmj.2019.0177] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 11/17/2019] [Indexed: 12/16/2022] Open
Abstract
Cancer incidence appears to be increased in both type 1 and type 2 diabetes mellitus (DM). DM represents a risk factor for cancer, particularly hepatocellular, hepatobiliary, pancreas, breast, ovarian, endometrial, and gastrointestinal cancers. In addition, there is evidence showing that DM is associated with increased cancer mortality. Common risk factors such as age, obesity, physical inactivity and smoking may contribute to increased cancer risk in patients with DM. Although the mechanistic process that may link diabetes to cancer is not completely understood yet, biological mechanisms linking DM and cancer are hyperglycemia, hyperinsulinemia, increased bioactivity of insulin-like growth factor 1, oxidative stress, dysregulations of sex hormones, and chronic inflammation. However, cancer screening rate is significantly lower in people with DM than that in people without diabetes. Evidence from previous studies suggests that some medications used to treat DM are associated with either increased or reduced risk of cancer. However, there is no strong evidence supporting the association between the use of anti-hyperglycemic medication and specific cancer. In conclusion, all patients with DM should be undergo recommended age- and sex appropriate cancer screenings to promote primary prevention and early detection. Furthermore, cancer should be screened in routine diabetes assessment.
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Affiliation(s)
- Sunghwan Suh
- Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea
| | - Kwang Won Kim
- Department of Internal Medicine, Gachon University Gil Medical Center, Gachon University College of Medicine, Incheon, Korea.
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Impact of BMI on peak growth hormone responses to provocative tests and therapeutic outcome in children with growth hormone deficiency. Sci Rep 2019; 9:16181. [PMID: 31700044 PMCID: PMC6838176 DOI: 10.1038/s41598-019-52644-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 10/15/2019] [Indexed: 12/15/2022] Open
Abstract
This study investigated the relationship between peak stimulated growth hormone (GH) and body mass index (BMI), as well as the impact of BMI on therapeutic response in patients with GH deficiency (GHD). A total of 460 patients were enrolled in the study. The patients were divided into four groups as per the etiology and peak GH values: idiopathic (n = 439), organic (n = 21), complete (n = 114), and partial (n = 325) GHD groups. Subsequently, they were classified as normal, overweight, or obese based on their BMI. There was no difference in BMI between complete and partial GHD. A significant negative relationship between peak GH and BMI were found. Moreover, obese GHD children had a considerably better therapeutic response in height increase and BMI decrease during 2 years of GH treatment compared to non-obese children with GHD. There was no difference between peak GH and type of GH stimulation test (GHST), except the clonidine test, which showed a much lower peak GH in obese GHD children. In conclusion, BMI had a negative impact on peak GH response, and therapeutic outcome was more favorable in the obese group. Despite no difference in GH response by type of GHST, the degree of obesity differentially affected the results.
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Shinohara S, Otsuki R, Kobayashi K, Matsuo M, Harada K, Sugaya M, Nakagawa M. The Prognostic Impact of Pericardial Fat Volumes in Resected Non-small Cell Lung Cancer. Ann Surg Oncol 2019; 27:481-489. [DOI: 10.1245/s10434-019-07703-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Indexed: 12/25/2022]
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Cignarelli A, Genchi VA, Caruso I, Natalicchio A, Perrini S, Laviola L, Giorgino F. Diabetes and cancer: Pathophysiological fundamentals of a 'dangerous affair'. Diabetes Res Clin Pract 2018; 143:378-388. [PMID: 29679627 DOI: 10.1016/j.diabres.2018.04.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 02/06/2023]
Abstract
Diabetes and cancer are worldwide chronic diseases with a major impact on the quality and expectancy of life. Metabolic abnormalities observed during the onset and progression of diabetes may have a critical role on the initiation and progression of carcinogenesis. To date, there are no conclusive data on the mechanisms underlying the relationship between diabetes and any type of human cancer. However, recent evidence suggests that both hyperglycemia and hyperinsulinemia in diabetes could elicit cell damage responses, such as glucotoxicity, lipotoxicity and oxidative stress, which participate in the cell transformation process raising the risk of cancer development. In addition, clinical trials have revealed that several anti-diabetes therapies may potentially affect the risk of cancer though largely undefined mechanisms. In this review, we highlight epidemiological and pathophysiological aspects of diabetes, which may influence cancer initiation and progression.
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Affiliation(s)
- Angelo Cignarelli
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Valentina Annamaria Genchi
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Irene Caruso
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Annalisa Natalicchio
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Sebastio Perrini
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Luigi Laviola
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Giorgino
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy.
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Stone TW, McPherson M, Gail Darlington L. Obesity and Cancer: Existing and New Hypotheses for a Causal Connection. EBioMedicine 2018; 30:14-28. [PMID: 29526577 PMCID: PMC5952217 DOI: 10.1016/j.ebiom.2018.02.022] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 02/12/2018] [Accepted: 02/23/2018] [Indexed: 02/07/2023] Open
Abstract
Existing explanations of obesity-associated cancer emphasise direct mutagenic effects of dietary components or hormonal imbalance. Some of these hypotheses are reviewed briefly, but recent evidence suggests a major role for chronic inflammation in cancer risk, possibly involving dietary content. These ideas include the inflammation-induced activation of the kynurenine pathway and its role in feeding and metabolism by activation of the aryl hydrocarbon receptor (AHR) and by modulating synaptic transmission in the brain. Evidence for a role of the kynurenine pathway in carcinogenesis then provides a potentially major link between obesity and cancer. A second new hypothesis is based on evidence that serine proteases can deplete cells of the tumour suppressors Deleted in Colorectal Cancer (DCC) and neogenin. These enzymes include mammalian chymotryptic proteases released by pro-inflammatory neutrophils and macrophages. Blood levels of chymotrypsin itself increase in parallel with food intake. The mechanistically similar bacterial enzyme subtilisin is widespread in the environment, animal probiotics, meat processing and cleaning products. Simple public health schemes in these areas, with selective serine protease inhibitors and AHR antagonists and could prevent a range of intestinal and other cancers.
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Affiliation(s)
- Trevor W Stone
- The Kennedy Institute, University of Oxford, Oxford OX3 7FY, UK; Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
| | - Megan McPherson
- School of Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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Fukumura D, Incio J, Shankaraiah RC, Jain RK. Obesity and Cancer: An Angiogenic and Inflammatory Link. Microcirculation 2016; 23:191-206. [PMID: 26808917 DOI: 10.1111/micc.12270] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 01/20/2016] [Indexed: 12/15/2022]
Abstract
With the current epidemic of obesity, a large number of patients diagnosed with cancer are overweight or obese. Importantly, this excess body weight is associated with tumor progression and poor prognosis. The mechanisms for this worse outcome, however, remain poorly understood. We review here the epidemiological evidence for the association between obesity and cancer, and discuss potential mechanisms focusing on angiogenesis and inflammation. In particular, we will discuss how the dysfunctional angiogenesis and inflammation occurring in adipose tissue in obesity may promote tumor progression, resistance to chemotherapy, and targeted therapies such as anti-angiogenic and immune therapies. Better understanding of how obesity fuels tumor progression and therapy resistance is essential to improve the current standard of care and the clinical outcome of cancer patients. To this end, we will discuss how an anti-diabetic drug such as metformin can overcome these adverse effects of obesity on the progression and treatment resistance of tumors.
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Affiliation(s)
- Dai Fukumura
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Joao Incio
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,I3S, Institute for Innovation and Research in Heath, Metabolism, Nutrition and Endocrinology Group, Biochemistry Department, Faculty of Medicine, Porto University, Porto, Portugal.,Department of Internal Medicine, Hospital S. João, Porto, Portugal
| | - Ram C Shankaraiah
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Morphology, Surgery and Experimental Medicine and Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Rakesh K Jain
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Abstract
The recent recognition of the clinical association between type 2 diabetes (T2D) and several types of human cancer has been further highlighted by reports of antidiabetic drugs treating or promoting cancer. At the cellular level, a plethora of molecules operating within distinct signaling pathways suggests cross-talk between the multiple pathways at the interface of the diabetes–cancer link. Additionally, a growing body of emerging evidence implicates homeostatic pathways that may become imbalanced during the pathogenesis of T2D or cancer or that become chronically deregulated by prolonged drug administration, leading to the development of cancer in diabetes and vice versa. This notion underscores the importance of combining clinical and basic mechanistic studies not only to unravel mechanisms of disease development but also to understand mechanisms of drug action. In turn, this may help the development of personalized strategies in which drug doses and administration durations are tailored to individual cases at different stages of the disease progression to achieve more efficacious treatments that undermine the diabetes–cancer association.
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Affiliation(s)
- Slavica Tudzarova
- Wolfson Institute for Biomedical Research, University College London, London WC1E6BT, UK
| | - Mahasin A Osman
- Department of Molecular Physiology, Pharmacology and Biotechnology, Division of Biology and Medicine, Warren Alpert Medical School, Brown University, Providence, RI 02912 Department of Chemistry and Forensic Sciences, College of Sciences and Technology, Savannah State University, Savannah, GA 41404
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Lewitt MS, Dent MS, Hall K. The Insulin-Like Growth Factor System in Obesity, Insulin Resistance and Type 2 Diabetes Mellitus. J Clin Med 2014; 3:1561-74. [PMID: 26237614 PMCID: PMC4470198 DOI: 10.3390/jcm3041561] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/21/2014] [Accepted: 12/05/2014] [Indexed: 12/11/2022] Open
Abstract
The insulin-like growth factor (IGF) system, acting in concert with other hormone axes, is important in normal metabolism. In obesity, the hyperinsulinaemia that accompanies peripheral insulin resistance leads to reduced growth hormone (GH) secretion, while total IGF-I levels are relatively unchanged due to increased hepatic GH sensitivity. IGF-binding protein (IGFBP)-1 levels are suppressed in relation to the increase in insulin levels in obesity and low levels predict the development of type 2 diabetes several years later. Visceral adiposity and hepatic steatosis, along with a chronic inflammation, contribute to the IGF system phenotype in individuals with metabolic syndrome and type 2 diabetes mellitus, including changes in the normal inverse relationship between IGFBP-1 and insulin, with IGFBP-1 concentrations that are inappropriately normal or elevated. The IGF system is implicated in the vascular and other complications of these disorders and is therefore a potential therapeutic target.
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Affiliation(s)
- Moira S Lewitt
- School of Health Nursing & Midwifery, the University of the West of Scotland, Paisley PA1 2BE, UK.
| | - Mairi S Dent
- School of Health Nursing & Midwifery, the University of the West of Scotland, Paisley PA1 2BE, UK.
| | - Kerstin Hall
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm SE171 76, Sweden.
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Oxidative Stress and DNA Damage in Obesity-Related Tumorigenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 824:5-17. [DOI: 10.1007/978-3-319-07320-0_2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Belobrajdic DP, Frystyk J, Jeyaratnaganthan N, Espelund U, Flyvbjerg A, Clifton PM, Noakes M. Moderate energy restriction-induced weight loss affects circulating IGF levels independent of dietary composition. Eur J Endocrinol 2010; 162:1075-82. [PMID: 20212016 DOI: 10.1530/eje-10-0062] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Obesity is associated with major changes in the circulating IGF system. However, it is not clear to what extent the IGF system is normalized following diet, and the possible role of different types of diet is also unknown. OBJECTIVE To compare changes in the circulating IGF system following 12 weeks of moderate energy restriction (7000 kJ/day) in overweight or obese males on a high protein high red meat diet (HP) or a high carbohydrate diet (HC). DESIGN Seventy-six men (mean age, 51+/-1.0 years; body mass index, 32.8+/-0.5 kg/m(2)) were allocated to matched groups treated with isocaloric diets of HP (n=34) or HC (n=42). Outcome measures were weight, body composition, IGF-related peptides, homoeostasis model assessment of insulin resistance (HOMA1-IR) and adipokines. RESULTS Weight loss did not differ between diets (HP 8.5+/-0.6 kg; HC 8.2+/-0.6 kg, P>0.05). IGF-related peptides increased total IGF1 (HP 23%; HC 18%, P<0.0001), bioactive IGF1 (HP 18%; HC 15%, P<0.002), IGF1:IGF-binding protein-3 (IGFBP-3; HP 29%; HC 22%, P<0.0001) and IGFBP-1 (HP 24%; HC 25%, P<0.01). By contrast, decreases were observed in IGFBP-3 (HP -4%; HC -3%, P<0.01), pro-IGF2 (HP -3%; HC -6%, P=0.001), total IGF2 (HP -7%; HC -3%, P=0.001) and sIGF2R (HP -10%; HC -6%, P<0.005). Only IGFBP-2 increased differentially by diet (HP 34%; HC 50%, P<0.0001, diet P<0.05). Adiponectin increased in both diets, but leptin and HOMA-IR decreased (P<0.001). CONCLUSIONS Weight loss induced by moderate energy restriction modulated the IGF system independent of dietary protein or red meat content. The effect of diet on IGFBP-2 appeared to have limited biological effect as total IGF2 and pro-IGF2 did not change.
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Affiliation(s)
- Damien P Belobrajdic
- Commonwealth Scientific Industrial Research Organisation (CSIRO), Food and Nutritional Sciences, Adelaide BC, South Australia, Australia.
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Rasmussen MH. Obesity, growth hormone and weight loss. Mol Cell Endocrinol 2010; 316:147-53. [PMID: 19723558 DOI: 10.1016/j.mce.2009.08.017] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Revised: 07/30/2009] [Accepted: 08/25/2009] [Indexed: 11/29/2022]
Abstract
Growth hormone (GH) is the most important hormonal regulator of postnatal longitudinal growth in man. In adults GH is no longer needed for longitudinal growth. Adults with growth hormone deficiency (GHD) are characterised by perturbations in body composition, lipid metabolism, cardiovascular risk profile and bone mineral density. It is well established that adult GHD usually is accompanied by an increase in fat accumulation and GH replacement in adult patients with GHD results in reduction of fat mass and abdominal fat mass in particular. It is also recognized that obesity and abdominal obesity in particular results in a secondary reduction in GH secretion and subnormal insulin-like growth factor-I (IGF-I) levels. The recovery of the GH IGF-I axis after weight loss suggest an acquired defect, however, the pathophysiologic role of GH in obesity is yet to be fully understood. In clinical studies examining the efficacy of GH in obese subjects very little or no effect are observed with respect to weight loss, whereas GH seems to reduce total and abdominal fat mass in obese subjects. The observed reductions in abdominal fat mass are modest and similar to what can be achieved by diet or exercise interventions.
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Affiliation(s)
- Michael Højby Rasmussen
- Department of Endocrinology, Hvidovre Hospital, University of Copenhagen, Copenhagen, Denmark.
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Arafat AM, Weickert MO, Frystyk J, Spranger J, Schöfl C, Möhlig M, Pfeiffer AFH. The role of insulin-like growth factor (IGF) binding protein-2 in the insulin-mediated decrease in IGF-I bioactivity. J Clin Endocrinol Metab 2009; 94:5093-101. [PMID: 19846739 DOI: 10.1210/jc.2009-0875] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Insulin interacts with the GH-IGF system by a reciprocal regulation of IGF-binding proteins (IGFBP) and GH, which in turn regulate insulin sensitivity via bioactive IGF-I. This network is linked to metabolic syndrome and cardiovascular diseases. OBJECTIVE We evaluated the effect of glucose and insulin on IGFBP-1-4, particularly IGFBP-2, in the regulation of bioactive IGF-I and its relation to insulin resistance. SETTING The study was conducted at an endocrinology center. RESEARCH DESIGN AND METHODS Twenty-four healthy subjects (12 men; aged 21-72 yr; body mass index 25.9 +/- 0.9 kg/m(2)) and 19 subjects with impaired glucose tolerance (IGT; eight men; aged 26-71 yr; body mass index 28.9 +/- 1.2 kg/m(2)) were prospectively studied using oral glucose tolerance test and hyperinsulinemic euglycemic clamp. RESULTS During the clamp, insulin decreased IGF-I bioactivity in both IGT subjects and controls (-16.2 +/- 2.8 and -13.9 +/- 3.3%, respectively; P < 0.01). In addition, insulin increased IGFBP-2 and GH and decreased IGFBP-1 and -4 but did not alter total IGF-I, IGF-II, or IGFBP-3 levels. During the oral glucose tolerance test, GH and IGFBP-1 were markedly suppressed. Subjects with IGT showed more pronounced insulin resistance and lower GH, IGFBP-1, and IGFBP-2 levels (P < 0.05). In multiple regression analysis, IGFBP-2 was an independent predictor of insulin sensitivity (beta = 0.36, P < 0.05) and IGF-I bioactivity (beta = -0.5, P < 0.05). CONCLUSIONS Our data indicate that insulin acutely decreases IGF-I bioactivity through differential modulation of IGFBPs. Furthermore, IGFBP-2 plays a central role in the insulin-IGF system cross talk and is closely linked to insulin resistance, thereby providing a further explanation for its association with the metabolic syndrome.
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Affiliation(s)
- Ayman M Arafat
- Department of Endocrinology, Diabetes, and Nutrition, Charité-University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany.
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van Kruijsdijk RCM, van der Wall E, Visseren FLJ. Obesity and cancer: the role of dysfunctional adipose tissue. Cancer Epidemiol Biomarkers Prev 2009; 18:2569-78. [PMID: 19755644 DOI: 10.1158/1055-9965.epi-09-0372] [Citation(s) in RCA: 500] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Overweight and obesity are health problems of epidemic proportions, increasing the risk not only of cardiovascular disease and type 2 diabetes mellitus but also of various types of cancer. Obesity is strongly associated with changes in the physiological function of adipose tissue, leading to insulin resistance, chronic inflammation, and altered secretion of adipokines. Several of these factors, such as insulin resistance, increased levels of leptin, plasminogen activator inhibitor-1, and endogenous sex steroids, decreased levels of adiponectin, and chronic inflammation, are involved in carcinogenesis and cancer progression. This article reviews these mechanisms, focusing on adipose tissue dysfunction as a unifying causal factor. Although understanding of the link between obesity and cancer might provide therapeutic targets, preventing overweight and obesity still remains number one priority.
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Affiliation(s)
- Rob C M van Kruijsdijk
- Department of Vascular Medicine, University Medical Center Utrecht, PO Box 85500, 3508 GA Utrecht, The Netherlands
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19
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Aasen G, Fagertun H, Halse J. Insulin resistance and dyslipidaemia in obese premenopausal and postmenopausal women matched for leg/trunk fat mass ratio. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 69:505-11. [DOI: 10.1080/00365510902778734] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Gunnar Aasen
- Spesialistsenteret Pilestredet Park, Oslo, Norway
| | | | - Johan Halse
- Spesialistsenteret Pilestredet Park, Oslo, Norway
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20
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Abstract
CONTEXT In obesity, total IGF-I is not reduced to the degree predicted by low GH levels, and free IGF-I levels are normal to high. Total and free IGF-I may not reflect IGF-I biological activity because immunoassays cannot account for the modifying effects of IGF binding proteins on interactions between IGF-I and its receptor. OBJECTIVE The aim of the study was to investigate the biological activity of IGF-I in obesity. DESIGN AND SETTING We conducted a cross-sectional study at a General Clinical Research Center. STUDY PARTICIPANTS Thirty-four healthy women (11 lean, 12 overweight, and 11 obese) of comparable age (overall mean, 30.7 +/- 1.3 yr) participated in the study. INTERVENTION There were no interventions. MAIN OUTCOME MEASURES We measured bioactive IGF-I (as measured by a kinase receptor activation assay), IGFBP-1, and GH using 6-h pools of serum collected every 10 min for 24 h, and fasting IGF-I and IGFBP-3. RESULTS Mean 24-h GH (R = -0.76; P < 0.0001), total IGF-I (R = -0.36; P = 0.040), and IGFBP-1 (R = -0.41; P = 0.017) levels were inversely associated with BMI, whereas bioactive IGF-I and IGFBP-3 levels were not. Mean bioactive IGF-I was similar in the groups [2.72 +/- 0.22 (lean), 3.10 +/- 0.32 (overweight), and 2.43 +/- 0.23 [corrected] (obese) microg/liter; overall P = 0.22]. Percentage bioactive IGF-I [(bioactive/total IGF-I) x 100] was higher in obese subjects than both lean and overweight subjects (P = 0.039). CONCLUSIONS Despite low GH secretion in obesity and decreasing IGFBP-1 with increasing BMI, 24-h mean bioactive IGF-I levels are not reduced in obese women and do not correlate with BMI or IGFBP-1 levels. This argues against elevated bioactive IGF-I as the etiology of reduced GH secretion through a feedback mechanism in obesity.
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Affiliation(s)
- J Frystyk
- Neuroendocrine Unit, Bulfinch 457B, Massachusetts General Hospital, Boston, MA 02114, USA
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21
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Rajpathak SN, McGinn AP, Strickler HD, Rohan TE, Pollak M, Cappola AR, Kuller L, Xue X, Newman AB, Strotmeyer ES, Psaty BM, Kaplan RC. Insulin-like growth factor-(IGF)-axis, inflammation, and glucose intolerance among older adults. Growth Horm IGF Res 2008; 18:166-173. [PMID: 17904401 PMCID: PMC2492581 DOI: 10.1016/j.ghir.2007.08.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Accepted: 08/15/2007] [Indexed: 11/19/2022]
Abstract
Increasing evidence suggests that the insulin-like growth factor (IGF)-axis may play a role in glucose metabolism and may also be associated with systemic inflammation. The aim of this study was to evaluate the association of insulin-like growth factor-1 (IGF-I) and its binding proteins, IGFBP-1 and IGFBP-3, with glucose intolerance and inflammation among older adults. We conducted a cross-sectional analysis in a in a random subsample (n=922) of the Cardiovascular Health Study (CHS), a prospective cohort of men and women > or = 65 years. Mean IGFBP-1 levels were significantly lower in older adults with impaired glucose tolerance (IGT), impaired fasting glucose (IFG) and diabetes compared to those with normal fasting and post-load glucose. High IGFBP-1 was associated with a reduced prevalence of IGT and IFG; the multivariable OR between extreme quartiles of IGFBP-1 was 0.60 (95% CI: 0.37, 0.95; p-trend: 0.03) for IGT and 0.41 (95% CI: 0.26, 0.64; p-trend: <0.01) for IFG. We did not find any significant association between IGF-I and glucose intolerance in this study and the association for IGFBP-3 was less clear. However, low levels of IGF-I and IGFBP-3 were associated with increased levels of markers of inflammation including C-reactive protein and interleukin-6 levels. We conclude that among adults > or = 65 years, low IGFBP-1 levels are associated with increased prevalence of glucose intolerance. We did not confirm prior associations of low IGF-I with glucose intolerance in this cohort of older individuals.
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Affiliation(s)
- Swapnil N Rajpathak
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 11375, USA.
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Rixhon M, Tichomirowa MA, Tamagno G, Daly AF, Beckers A. Current and future perspectives on recombinant growth hormone for the treatment of obesity. Expert Rev Endocrinol Metab 2008; 3:75-90. [PMID: 30743787 DOI: 10.1586/17446651.3.1.75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The similarities between patients with untreated growth hormone (GH) deficiency and those with the cardiometabolic syndrome and the beneficial effects of recombinant human GH (rhGH) on body composition have led to the hypothesis that rhGH treatment may have utility in obesity. GH release is reduced in the setting of obesity, primarily due to hyperinsulinism and increased free fatty acid levels. We reviewed the outcomes of 23 clinical studies carried out between 1987 and 2006 that examined the effects of rhGH administration in the obese state. Typically, changes in overall body weight do not occur with rhGH therapy; however, assessment of body composition demonstrates reductions in visceral abdominal fat. Data on the effects of rhGH on lipid and carbohydrate metabolic profiles in obese patients are less clear-cut, with a subset of studies showing a beneficial effect and others a neutral effect. Given the increasing burden of obesity in the general population and the current paucity of effective therapies, it is useful to consider the data on rhGH and obesity from a clinical perspective to highlight potential treatment strategies that harness the somatotropic axis.
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Affiliation(s)
- Martine Rixhon
- a Department Universitaire de Médecine Générale, University of Liège, Liège, Belgium
| | - Maria A Tichomirowa
- b Department of Endocrinology, CHU de Liège, University of Liège, Liège, Belgium
| | - Gianluca Tamagno
- b Department of Endocrinology, CHU de Liège, University of Liège, Liège, Belgium
| | - Adrian F Daly
- b Department of Endocrinology, CHU de Liège, University of Liège, Liège, Belgium
| | - Albert Beckers
- c Department of Endocrinology, CHU de Liège, 4000 Liège, Belgium.
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Harish K, Dharmalingam M, Himanshu M. Study Protocol: insulin and its role in cancer. BMC Endocr Disord 2007; 7:10. [PMID: 17953765 PMCID: PMC2151943 DOI: 10.1186/1472-6823-7-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Accepted: 10/22/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Studies have shown that metabolic syndrome and its consequent biochemical derangements in the various phases of diabetes may contribute to carcinogenesis. A part of this carcinogenic effect could be attributed to hyperinsulinism. High levels of insulin decrease the production of IGF-1 binding proteins and hence increase levels of free IGF-1. It is well established that bioactivity of free insulin growth factor 1 (IGF-1) increases tumor turnover rate. The objective is to investigate the role of insulin resistance/sensitivity in carcinogenesis by studying the relation between insulin resistance/sensitivity and IGF-1 levels in cancer patients. We postulate that hyperinsulinaemia which prevails during initial phases of insulin resistance (condition prior to overt diabetes) increases bioactivity of free IGF-1, which may contribute to process of carcinogenesis. METHODS/DESIGN Based on our pilot study results and power analysis of the same, we have designed a two group case-control study. 800 proven untreated cancer patients (solid epithelial cell tumors) under age of 50 shall be recruited with 200 healthy subjects serving as controls. Insulin resistance/sensitivity and free IGF-1 levels shall be determined in all subjects. Association between the two parameters shall be tested using suitable statistical methods. DISCUSSION Well controlled studies in humans are essential to study the link between insulin resistance, hyperinsulinaemia, IGF-1 and carcinogenesis. This study could provide insights to the role of insulin, insulin resistance, IGF-1 in carcinogenesis although a precise role and the extent of influence cannot be determined. In future, cancer prevention and treatment strategies could revolve around insulin and insulin resistance.
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Affiliation(s)
- K Harish
- Department of Surgical Oncology, M. S. Ramaiah Medical College & Hospital, Bangalore 560054, India
| | - M Dharmalingam
- Department of Endocrinology, M. S. Ramaiah Medical College & Hospital, Bangalore 560054, India
| | - M Himanshu
- Department of Endocrinology, M. S. Ramaiah Medical College & Hospital, Bangalore 560054, India
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Rasmussen MH, Juul A, Hilsted J. Effect of weight loss on free insulin-like growth factor-I in obese women with hyposomatotropism. Obesity (Silver Spring) 2007; 15:879-86. [PMID: 17426323 DOI: 10.1038/oby.2007.607] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE It has been hypothesized that increased free insulin-like growth factor (IGF)-I levels generated from an increase in IGF-binding protein (IGFBP) protease activity could be the inhibitory mechanism for the decreased growth hormone (GH) secretion observed in obese subjects. RESEARCH METHODS AND PROCEDURES In this study, we determined basal and 24-hour levels of free IGF-I and -II, total IGF-I and -II, IGFBP-1, as well as basal IGFBP-2, -3, and -4, acid-labile subunit (ALS), IGFBP-1, -2, and -3 protease activity, and 24-hour GH release in obese women before and after a diet-induced weight loss. Sixteen obese women (age, 29.5+/-1.4 years) participated in a weight loss program and 16 age-matched non-obese women served as controls. RESULTS Circulating free IGF-I and 24-hour GH release were significantly decreased in obese women at before weight loss compared with non-obese women (1.29+/-0.12 vs. 0.60+/-0.09 microg/L; p<0.001 and 862+/-90 vs. 404+/-77 mU/24 hours; p<0.001, respectively). Free IGF-I and 24-hour GH release were not inversely correlated to each other. IGFBP-1 and -2 levels were decreased, whereas ALS, IGFBP-3 and -4, and IGFBP-1, -2, and -3 protease activity were similar in obese and non-obese women. Eight of the 16 obese women achieved an average weight loss of 30+/-5 kg during 26 to 60 weeks of dieting. After the considerable weight loss, significant differences in free IGF-I, GH release, and IGFBP-1 and -2 levels were no longer present between previously obese and non-obese women. DISCUSSION We showed that circulating free IGF-I is markedly decreased in severely obese women and does not per se mediate the concomitant hyposomatotropism. The decreased levels of free IGF-I seem to be transient and restored to normal levels after weight loss.
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Affiliation(s)
- Michael H Rasmussen
- Department of Endocrinology, Hvidovre Hospital, University of Copenhagen, Denmark.
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Flanagan DE, Holt RIG, Owens PC, Cockington RJ, Moore VM, Robinson JS, Godsland IF, Phillips DIW. Gender differences in the insulin-like growth factor axis response to a glucose load. Acta Physiol (Oxf) 2006; 187:371-8. [PMID: 16776662 DOI: 10.1111/j.1748-1716.2006.01581.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS The insulin-like growth factors (IGFs) are thought to contribute to glucose homeostasis. The aim of our study was to examine the response of the IGFs and their binding proteins to an intravenous load of glucose in a cohort of young men and women with normal glucose tolerance. METHODS The intravenous glucose tolerance test (IVGTT) was used to quantify insulin sensitivity and insulin secretion in 160 adults aged 20-21 years in Adelaide, Australia. Serum IGF-I, IGF-II, IGF-binding protein (IGFBP)-1 and IGFBP-3 were measured during the IVGTT. RESULTS Women were less insulin sensitive than men with higher fasting insulin (women 55.6 +/- 4.4, men 44.1 +/- 3.6 pmol L(-1), P = 0.001) and first phase insulin secretion (women 3490 +/- 286, men 3038 +/- 271 pmol L(-1) min, P = 0.042). Women showed lower fasting free IGF-I (women 0.29 +/- 0.02, men 0.36 +/- 0.02 mug L(-1), P = 0.004) but higher IGFBP-3 (women 46.3 +/- 0.53, men 43.3 +/- 0.58 mg dL(-1), P = 0.001) and higher IGFBP-1 concentrations (women 37.0 +/- 2.9, men 24.8 +/- 2.3 mug L(-1), P = 0.012). IGFBP-1 fell by 5 min and remained suppressed. IGFBP-3 and total IGF-I fell until 60 min rising again by 2 h. IGF and IGFBP values were all higher in women. IGFBP-1 showed a negative association with fasting and stimulated insulin concentrations in both genders. First phase insulin secretion however showed positive correlations with IGFBP-3 (r = 0.321, P = 0.004) and IGF-I (r = 0.339 P = 0.002) in men but not women. CONCLUSION Our data show that IGFBP-1, IGFBP-3 and IGF-I show acute changes following a glucose load and there are marked gender differences in these responses.
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Affiliation(s)
- D E Flanagan
- Department of Endocrinology, Peninsula Medical School, Derriford Hospital, Plymouth, UK
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Frystyk J. Free insulin-like growth factors -- measurements and relationships to growth hormone secretion and glucose homeostasis. Growth Horm IGF Res 2004; 14:337-375. [PMID: 15336229 DOI: 10.1016/j.ghir.2004.06.001] [Citation(s) in RCA: 241] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
IGF-I is a multipotent growth factor with important actions on normal tissue growth and regeneration. In addition, IGF-I has been suggested to have beneficial effects on glucose homeostasis due to its glucose lowering and insulin sensitizing actions. However, not all effects of IGF-I are considered to be favorable; thus, epidemiological studies suggest that IGF-I is also involved in the development of common cancers, atherosclerosis and type 2 diabetes. The biological actions of IGF-I are modulated by at least six IGF-binding proteins, which bind approximately 99% of the circulating IGF-I pool. So far, most in vivo studies have used serum or plasma total (extractable IGF-I) as an estimate of the bioactivity of IGF-I in vivo. However, within the last decade, validated assays for measurement of free IGF-I have been described. This review aims to discuss the current assays for free IGF-I and their advances in relation to the traditional measurement of total IGF-I. The literature overview will focus on the role of circulating free versus total IGF-I in the feedback regulation of GH release, and the possible involvement of the circulating IGF-system in glucose homeostasis.
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Affiliation(s)
- Jan Frystyk
- Medical Research Laboratories and Medical Department M, Aarhus University Hospital, Norrebrogade, Aarhus, Denmark.
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Ricart W, Fernández-Real JM. [Impact of hormonal deficit and cardiovascular risk factors on life expectancy in hypopituitarism]. Med Clin (Barc) 2003; 120:630-7. [PMID: 12732130 DOI: 10.1016/s0025-7753(03)73792-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Wifredo Ricart
- Unidat de Diabetes, Endocrinología y Nutrición. Hospital Universitari Dr. Josep Trueta. Girona. España.
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Abstract
Insulin resistance and compensatory hyperinsulinaemia are thought to be the underlying factors in the metabolic or insulin-resistance syndrome and can be controlled by diet and exercise. Hyperinsulinaemia has been shown to have a direct effect on the live, suppressing the production of sex hormone-binding globulin (SHBG) and insulin-like growth factor-binding proteins 1 and 2 (IGFBP-1, -2) while stimulating the production of insulin-like growth factor 1 (IGF-1). These factors have been proposed to be important modulators of hormone-related cancers, such as prostate cancer. Men adopting a low-fat diet and daily exercise reduced their levels of serum insulin and IGF-1, while increasing their levels of IGFBP-1 and sex hormone-binding globulin (SHBG). Cell-culture studies with LNCaP prostate cancer cells showed apoptosis of tumour cells and a reduction in serum-stimulated cell growth in the post diet and exercise serum. These results suggest that prostate cancer may be another aspect of the insulin-resistance syndrome and that adopting a low-fat diet combined with regular exercise may reduce the risk for prostate and other hormone-related cancers. This needs to be tested with prospective studies.
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