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Abstract
Insulin action is impaired in type 2 diabetes. The functions of the hormone are an integrated product of insulin secretion from pancreatic β-cells and insulin clearance by receptor-mediated endocytosis and degradation, mostly in liver (hepatocytes) and, to a lower extent, in extrahepatic peripheral tissues. Substantial evidence indicates that genetic or acquired abnormalities of insulin secretion or action predispose to type 2 diabetes. In recent years, along with the discovery of the molecular foundation of receptor-mediated insulin clearance, such as through the membrane glycoprotein CEACAM1, a consensus has begun to emerge that reduction of insulin clearance contributes to the disease process. In this review, we consider the evidence suggesting a pathogenic role for reduced insulin clearance in insulin resistance, obesity, hepatic steatosis, and type 2 diabetes.
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Affiliation(s)
- Sonia M Najjar
- Department of Biomedical Sciences and the Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, USA;
| | - Sonia Caprio
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Amalia Gastaldelli
- Cardiometabolic Risk Unit, Institute of Clinical Physiology-National Research Council, Pisa, Italy
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Sleeve Gastrectomy-Induced Weight Loss Increases Insulin Clearance in Obese Mice. Int J Mol Sci 2023; 24:ijms24021729. [PMID: 36675244 PMCID: PMC9861800 DOI: 10.3390/ijms24021729] [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: 11/06/2022] [Revised: 01/06/2023] [Accepted: 01/07/2023] [Indexed: 01/18/2023] Open
Abstract
Sleeve gastrectomy (SG) successfully recovers metabolic homeostasis in obese humans and rodents while also resulting in the normalization of insulin sensitivity and insulinemia. Reduced insulin levels have been attributed to lower insulin secretion and increased insulin clearance in individuals submitted to SG. Insulin degradation mainly occurs in the liver in a process controlled, at least in part, by the insulin-degrading enzyme (IDE). However, research has yet to explore whether liver IDE expression or activity is altered after SG surgery. In this study, C57BL/6 mice were fed a chow (CTL) or high-fat diet (HFD) for 10 weeks. Afterward, the HFD mice were randomly assigned to two groups: sham-surgical (HFD-SHAM) and SG-surgical (HFD-SG). Here, we confirmed that SG improves glucose-insulin homeostasis in obese mice. Additionally, SG reduced insulinemia by reducing insulin secretion, assessed by the analysis of plasmatic C-peptide content, and increasing insulin clearance, which was evaluated through the calculation of the plasmatic C-peptide:insulin ratio. Although no changes in hepatic IDE activity were observed, IDE expression was higher in the liver of HFD-SG compared with HFD-SHAM mice. These results indicate that SG may be helpful to counteract obesity-induced hyperinsulinemia by increasing insulin clearance, likely through enhanced liver IDE expression.
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Ladwa M, Bello O, Hakim O, Boselli ML, Shojaee-Moradie F, Umpleby AM, Peacock J, Amiel SA, Bonadonna RC, Goff LM. Exploring the determinants of ethnic differences in insulin clearance between men of Black African and White European ethnicity. Acta Diabetol 2022; 59:329-337. [PMID: 34661756 PMCID: PMC8863750 DOI: 10.1007/s00592-021-01809-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 10/03/2021] [Indexed: 11/27/2022]
Abstract
AIM People of Black African ancestry, who are known to be at disproportionately high risk of type 2 diabetes (T2D), typically exhibit lower hepatic insulin clearance compared with White Europeans. However, the mechanisms underlying this metabolic characteristic are poorly understood. We explored whether low insulin clearance in Black African (BA) men could be explained by insulin resistance, subclinical inflammation or adiponectin concentrations. METHODS BA and White European (WE) men, categorised as either normal glucose tolerant (NGT) or with T2D, were recruited to undergo the following: a mixed meal tolerance test with C-peptide modelling to determine endogenous insulin clearance; fasting serum adiponectin and cytokine profiles; a hyperinsulinaemic-euglycaemic clamp to measure whole-body insulin sensitivity; and magnetic resonance imaging to quantify visceral adipose tissue. RESULTS Forty BA (20 NGT and 20 T2D) and 41 WE (23 NGT and 18 T2D) men were studied. BA men had significantly lower insulin clearance (P = 0.011) and lower plasma adiponectin (P = 0.031) compared with WE men. In multiple regression analysis, ethnicity, insulin sensitivity and plasma adiponectin were independent predictors of insulin clearance, while age, visceral adiposity and tumour necrosis factor alpha (TNF-α) did not significantly contribute to the variation. CONCLUSION These data suggest that adiponectin may play a direct role in the upregulation of insulin clearance beyond its insulin-sensitising properties.
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Affiliation(s)
- Meera Ladwa
- Diabetes Research Group, Department of Nutritional Sciences, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, Franklin-Wilkins Building, Room 3.87, Waterloo Campus, London, SE1 9NH, UK
| | - Oluwatoyosi Bello
- Diabetes Research Group, Department of Nutritional Sciences, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, Franklin-Wilkins Building, Room 3.87, Waterloo Campus, London, SE1 9NH, UK
| | - Olah Hakim
- Diabetes Research Group, Department of Nutritional Sciences, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, Franklin-Wilkins Building, Room 3.87, Waterloo Campus, London, SE1 9NH, UK
| | - Maria Linda Boselli
- Division of Endocrinology and Metabolic Disease, University of Verona School of Medicine, Verona, Italy
| | | | - A Margot Umpleby
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Janet Peacock
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Stephanie A Amiel
- Diabetes Research Group, Department of Nutritional Sciences, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, Franklin-Wilkins Building, Room 3.87, Waterloo Campus, London, SE1 9NH, UK
| | - Riccardo C Bonadonna
- Department of Medicine and Surgery, University of Parma and Azienda Ospedaliera Universitaria di Parma, Parma, Italy
| | - Louise M Goff
- Diabetes Research Group, Department of Nutritional Sciences, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, Franklin-Wilkins Building, Room 3.87, Waterloo Campus, London, SE1 9NH, UK.
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Bergman RN, Kabir M, Ader M. The Physiology of Insulin Clearance. Int J Mol Sci 2022; 23:1826. [PMID: 35163746 PMCID: PMC8836929 DOI: 10.3390/ijms23031826] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/02/2022] [Accepted: 02/02/2022] [Indexed: 02/05/2023] Open
Abstract
In the 1950's, Dr. I. Arthur Mirsky first recognized the possible importance of insulin degradation changes to the pathogenesis of type 2 diabetes. While this mechanism was ignored for decades, insulin degradation is now being recognized as a possible factor in diabetes risk. After Mirsky, the relative importance of defects in insulin release and insulin resistance were recognized as risk factors. The hyperbolic relationship between secretion and sensitivity was introduced, as was the relationship between them, as expressed as the disposition index (DI). The DI was shown to be affected by environmental and genetic factors, and it was shown to be differentiated among ethnic groups. However, the importance of differences in insulin degradation (clearance) on the disposition index relationship remains to be clarified. Direct measure of insulin clearance revealed it to be highly variable among even normal individuals, and to be affected by fat feeding and other physiologic factors. Insulin clearance is relatively lower in ethnic groups at high risk for diabetes such as African Americans and Hispanic Americans, compared to European Americans. These differences exist even for young children. Two possible mechanisms have been proposed for the importance of insulin clearance for diabetes risk: in one concept, insulin resistance per se leads to reduced clearance and diabetes risk. In a second and new concept, reduced degradation is a primary factor leading to diabetes risk, such that lower clearance (resulting from genetics or environment) leads to systemic hyperinsulinemia, insulin resistance, and beta-cell stress. Recent data by Chang and colleagues appear to support this latter hypothesis in Native Americans. The importance of insulin clearance as a risk factor for metabolic disease is becoming recognized and may be treatable.
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Affiliation(s)
- Richard N. Bergman
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; (M.K.); (M.A.)
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Racial differences in psychological stress and insulin sensitivity in non-Hispanic Black and White adolescents with overweight/obesity. Physiol Behav 2021; 245:113672. [PMID: 34902427 DOI: 10.1016/j.physbeh.2021.113672] [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: 09/04/2021] [Revised: 12/05/2021] [Accepted: 12/09/2021] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Racial differences in type 2 diabetes risk persist among non-Hispanic Black and non-Hispanic White adolescents with overweight/obesity; however, the role of psychological stress in this disparity is less clear. PURPOSE To examine racial differences in the association between psychological stress, insulin sensitivity (Si), acute insulin response to glucose (AIRg), and disposition index (DI) among non-Hispanic Black and non-Hispanic White adolescents with overweight/obesity. METHODS Ninety-six adolescents (60% female; 51% non-Hispanic Black; 16.6 ± 1.8 years of age) with overweight/obesity (BMI percentile ≥ 85th percentile) were included in this analysis. Psychological stress was assessed using the 14-item Perceived Stress Scale. Glucose and insulin data from an intravenous glucose tolerance test was modeled to obtain Si, AIRg, and DI. Multivariable linear regression models were used to examine the association between race, psychological stress and metabolic outcomes (Si, AIRg, and DI). RESULTS Race was a significant predictor of log-AIRg and log-DI (ps < 0.05) independent of all covariates in the main effect models. Lower Si (pinteraction = 0.014) and DI (pinteraction = 0.012) was also observed among Black adolescents who reported higher stress levels, whereas higher Si and DI was observed among non-Hispanic White adolescents reporting higher stress in the race interaction models. Race however, did not moderate the association between psychological stress and AIRg (p > 0.05), nor was stress associated with Si, AIRg, or DI ("p" "s" > 0.05) across all other models. CONCLUSIONS Psychological stress may play an important and distinct role in shaping racial differences in type 2 diabetes risk among adolescents with overweight/obesity. Additional research is needed to understand the long-term effects of psychological stress on metabolic health among non-Hispanic Black and non-Hispanic White adolescents with overweight/obesity.
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Fortuin-de Smidt MC, Mendham AE, Hauksson J, Alhamud A, Stefanovski D, Hakim O, Swart J, Goff LM, Kahn SE, Olsson T, Goedecke JH. β-cell function in black South African women: exploratory associations with insulin clearance, visceral and ectopic fat. Endocr Connect 2021; 10:550-560. [PMID: 33884957 PMCID: PMC8183622 DOI: 10.1530/ec-21-0153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 04/22/2021] [Indexed: 11/08/2022]
Abstract
The role of ectopic fat, insulin secretion and clearance in the preservation ofβ-cell function in black African women with obesity who typically present with hyperinsulinaemia is not clear. We aim to examine the associations between disposition index (DI, an estimate of β-cell function), insulin secretion and clearance and ectopic fat deposition. This is a cross-sectional study of 43 black South African women (age 20-35 years) with obesity (BMI 30-40 kg/m2) and without type 2 diabetes that measured the following: DI, insulin sensitivity (SI), acute insulin response (AIRg), insulin secretion rate (ISR), hepatic insulin extraction and peripheral insulin clearance (frequently sampled i.v. glucose tolerance test); pancreatic and hepatic fat, visceral adipose tissue (VAT) and abdominal s.c. adipose tissue (aSAT) volume (MRI), intra-myocellular (IMCL) and extra-myocellular fat content (EMCL) (magnetic resonance spectroscopy). DI correlated positively with peripheral insulin clearance (β 55.80, P = 0.002). Higher DI was associated with lower VAT, pancreatic fat and soleus fat, but VAT explained most of the variance in DI (32%). Additionally, higher first phase ISR (P = 0.033) and lower hepatic insulin extraction (P = 0.022) were associated with lower VAT, independent from SI, rather than with ectopic fat. In conclusion, peripheral insulin clearance emerged as an important correlate of DI. However, VAT was the main determinant of a lower DI above ectopic fat depots. Importantly, VAT, but not ectopic fat, is associated with both lower insulin secretion and higher hepatic insulin extraction. Prevention of VAT accumulation in young black African women should, therefore, be an important target for beta cell preservation.
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Affiliation(s)
- Melony C Fortuin-de Smidt
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
- Correspondence should be addressed to M C Fortuin-de Smidt:
| | - Amy E Mendham
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
| | - Jon Hauksson
- Department of Radiation Sciences, Radiation Physics and Biomedical Engineering, Umea University, Umea, Sweden
| | - Ali Alhamud
- Department of Human Biology, MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa
- The Modern Pioneer Center and ArSMRM for MRI Training and Development, Tripoli, Libya
| | - Darko Stefanovski
- Department of Clinical Studies, New Bolton Centre, University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
| | - Olah Hakim
- Department of Diabetes, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King’s College London, London, UK
| | - Jeroen Swart
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Louise M Goff
- Department of Diabetes, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King’s College London, London, UK
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, Veterans Affairs Puget Sound Health Care System, University of Washington, Seattle, Washington, USA
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Umea University, Umea, Sweden
| | - Julia H Goedecke
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
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Bergman RN, Piccinini F. Response to Comment on Piccinini and Bergman The Measurement of Insulin Clearance. Diabetes Care 2020;43:2296-2302. Diabetes Care 2021; 44:e100-e101. [PMID: 33972319 PMCID: PMC8132327 DOI: 10.2337/dci20-0080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Borges DO, Patarrão RS, Ribeiro RT, de Oliveira RM, Duarte N, Belew GD, Martins M, Andrade R, Costa J, Correia I, Boavida JM, Duarte R, Gardete-Correia L, Medina JL, Raposo JF, Jones JG, Penha-Gonçalves C, Macedo MP. Loss of postprandial insulin clearance control by Insulin-degrading enzyme drives dysmetabolism traits. Metabolism 2021; 118:154735. [PMID: 33631143 DOI: 10.1016/j.metabol.2021.154735] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/10/2021] [Accepted: 02/15/2021] [Indexed: 02/05/2023]
Abstract
Systemic insulin availability is determined by a balance between beta-cell secretion capacity and insulin clearance (IC). Insulin-degrading enzyme (IDE) is involved in the intracellular mechanisms underlying IC. The liver is a major player in IC control yet the role of hepatic IDE in glucose and lipid homeostasis remains unexplored. We hypothesized that IDE governs postprandial IC and hepatic IDE dysfunction amplifies dysmetabolic responses and prediabetes traits such as hepatic steatosis. In a European/Portuguese population-based cohort, IDE SNPs were strongly associated with postprandial IC in normoglycemic men but to a considerably lesser extent in women or in subjects with prediabetes. Liver-specific knockout-mice (LS-IDE KO) under normal chow diet (NCD), showed reduced postprandial IC with glucose intolerance and under high fat diet (HFD) were more susceptible to hepatic steatosis than control mice. This suggests that regulation of IC by IDE contributes to liver metabolic resilience. In agreement, LS-IDE KO hepatocytes revealed reduction of Glut2 expression levels with consequent impairment of glucose uptake and upregulation of CD36, a major hepatic free fatty acid transporter. Together these findings provide strong evidence that dysfunctional IC due to abnormal IDE regulation directly impairs postprandial hepatic glucose disposal and increases susceptibility to dysmetabolic conditions in the setting of Western diet/lifestyle.
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Affiliation(s)
- Diego O Borges
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School-FCM, Universidade Nova de Lisboa, Lisboa, Portugal; Molecular Biosciences PhD Program, Instituto de Tecnologia Química e Biológica António Xavier - ITQB NOVA, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Rita S Patarrão
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School-FCM, Universidade Nova de Lisboa, Lisboa, Portugal; Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Rogério T Ribeiro
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal; Departamento de Ciências Médicas, Instituto de Biomedicina - iBiMED, Universidade de Aveiro, Aveiro, Portugal
| | - Rita Machado de Oliveira
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School-FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Nádia Duarte
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | | | | | - Rita Andrade
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - João Costa
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Isabel Correia
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - José Manuel Boavida
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - Rui Duarte
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - Luís Gardete-Correia
- Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | | | - João F Raposo
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School-FCM, Universidade Nova de Lisboa, Lisboa, Portugal; Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - John G Jones
- APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal; Center for Neurosciences and Cell Biology, University of Coimbra, Portugal
| | - Carlos Penha-Gonçalves
- Instituto Gulbenkian de Ciência, Oeiras, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal
| | - M Paula Macedo
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School-FCM, Universidade Nova de Lisboa, Lisboa, Portugal; Sociedade Portuguesa de Diabetologia, Lisboa, Portugal; APDP-Diabetes Portugal Education and Research Center (APDP-ERC), Lisboa, Portugal; Departamento de Ciências Médicas, Instituto de Biomedicina - iBiMED, Universidade de Aveiro, Aveiro, Portugal.
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Ladwa M, Bello O, Hakim O, Shojaee-Moradie F, Boselli L, Charles-Edwards G, Stadler M, Peacock JL, Umpleby AM, Amiel SA, Bonadonna RC, Goff LM. Insulin clearance as the major player in the hyperinsulinaemia of black African men without diabetes. Diabetes Obes Metab 2020; 22:1808-1817. [PMID: 32488928 DOI: 10.1111/dom.14101] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/14/2020] [Accepted: 05/27/2020] [Indexed: 12/14/2022]
Abstract
AIM To investigate relationships between insulin clearance, insulin secretion, hepatic fat accumulation and insulin sensitivity in black African (BA) and white European (WE) men. METHODS Twenty-three BA and twenty-three WE men with normal glucose tolerance, matched for age and body mass index, underwent a hyperglycaemic clamp to measure insulin secretion and clearance, hyperinsulinaemic-euglycaemic clamp with stable glucose isotope infusion to measure whole-body and hepatic-specific insulin sensitivity, and magnetic resonance imaging to quantify intrahepatic lipid (IHL). RESULTS BA men had higher glucose-stimulated peripheral insulin levels (48.1 [35.5, 65.2] × 103 vs. 29.9 [23.3, 38.4] × 103 pmol L-1 × min, P = .017) and lower endogeneous insulin clearance (771.6 [227.8] vs. 1381 [534.3] mL m-2 body surface area min -1 , P < .001) compared with WE men. There were no ethnic differences in beta-cell insulin secretion or beta-cell responsivity to glucose, even after adjustment for prevailing insulin sensitivity. In WE men, endogenous insulin clearance was correlated with whole-body insulin sensitivity (r = 0.691, P = .001) and inversely correlated with IHL (r = -0.674, P = .001). These associations were not found in BA men. CONCLUSIONS While normally glucose-tolerant BA men have similar insulin secretory responses to their WE counterparts, they have markedly lower insulin clearance, which does not appear to be explained by either insulin resistance or hepatic fat accumulation. Low insulin clearance may be the primary mechanism of hyperinsulinaemia in populations of African origin.
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Affiliation(s)
- Meera Ladwa
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Oluwatoyosi Bello
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Olah Hakim
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | | | - Linda Boselli
- Division of Endocrinology and Metabolic Disease, University of Verona School of Medicine, Verona, Italy
| | - Geoff Charles-Edwards
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Marietta Stadler
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Janet L Peacock
- School of Population Health and Environmental Sciences, King's College London, London, UK
| | | | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Riccardo C Bonadonna
- Department of Medicine & Surgery, University of Parma and Azienda Ospedaliera Universitaria di Parma, Parma, Italy
| | - Louise M Goff
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
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Piccinini F, Bergman RN. The Measurement of Insulin Clearance. Diabetes Care 2020; 43:2296-2302. [PMID: 32910777 PMCID: PMC7440908 DOI: 10.2337/dc20-0750] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 04/14/2020] [Indexed: 02/03/2023]
Abstract
Insulin clearance has recently been highlighted as a fundamental aspect of glucose metabolism, as it has been hypothesized that its impairment could be related to an increased risk of developing type 2 diabetes. This review focuses on methods used to calculate insulin clearance: from the early surrogate indices employing C-peptide:insulin molar ratio, to direct measurement methods used in animal models, to modeling-based techniques to estimate the components of insulin clearance (hepatic versus extrahepatic). The methods are explored and interpreted by critically highlighting advantages and limitations.
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Affiliation(s)
- Francesca Piccinini
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Richard N Bergman
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
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Tura A, Göbl C, Morettini M, Burattini L, Kautzky-Willer A, Pacini G. Insulin clearance is altered in women with a history of gestational diabetes progressing to type 2 diabetes. Nutr Metab Cardiovasc Dis 2020; 30:1272-1280. [PMID: 32513580 DOI: 10.1016/j.numecd.2020.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/27/2020] [Accepted: 04/06/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND AND AIMS Insulin clearance is a relevant process in glucose homeostasis. In this observational study, we aimed to assess insulin clearance (ClINS) in women with former gestational diabetes (fGDM) both early after delivery and after a follow-up. METHODS AND RESULTS We analysed 59 fGDM women, and 16 women not developing GDM (CNT). All women underwent an oral glucose tolerance test (OGTT) yearly, and an insulin-modified intravenous glucose tolerance test (IVGTT) at baseline and at follow-up end (until 7 years). Both IVGTT and OGTT ClINS was assessed as insulin secretion to plasma insulin ratio. We also defined IVGTT first (0-10 min) and second phase (10-180 min) ClINS. We found that 14 fGDM women progressed to type 2 diabetes (PROG), whereas 45 women remained diabetes-free (NONPROG). At baseline, IVGTT ClINS showed alterations in PROG, especially in second phase (0.88 ± 0.10 l·min-1 in PROG, 0.60 ± 0.06 in NONPROG, 0.54 ± 0.07 in CNT, p ≤ 0.03). Differences in ClINS were not found from OGTT. Cox regression analysis showed second phase ClINS as significant type 2 diabetes predictor (hazard ratio = 1.90, 95% confidence interval 1.09-3.30, p = 0.02). CONCLUSION This study showed that insulin clearance derived from an insulin-modified IVGTT is notably altered in women with history of GDM progressing towards type 2 diabetes.
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Affiliation(s)
- Andrea Tura
- Metabolic Unit, CNR Institute of Neuroscience, Padova, Italy.
| | - Christian Göbl
- Department of Obstetrics and Gynecology, Division of Obstetrics and Feto-Maternal Medicine, Medical University of Vienna, Vienna, Austria
| | - Micaela Morettini
- Department of Information Engineering, Università Politecnica delle Marche, Ancona, Italy
| | - Laura Burattini
- Department of Information Engineering, Università Politecnica delle Marche, Ancona, Italy
| | - Alexandra Kautzky-Willer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Giovanni Pacini
- Metabolic Unit, CNR Institute of Neuroscience, Padova, Italy
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Smith GI, Polidori DC, Yoshino M, Kearney ML, Patterson BW, Mittendorfer B, Klein S. Influence of adiposity, insulin resistance, and intrahepatic triglyceride content on insulin kinetics. J Clin Invest 2020; 130:3305-3314. [PMID: 32191646 PMCID: PMC7260030 DOI: 10.1172/jci136756] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/11/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUNDInsulin is a key regulator of metabolic function. The effects of excess adiposity, insulin resistance, and hepatic steatosis on the complex integration of insulin secretion and hepatic and extrahepatic tissue extraction are not clear.METHODSA hyperinsulinemic-euglycemic clamp and a 3-hour oral glucose tolerance test were performed to evaluate insulin sensitivity and insulin kinetics after glucose ingestion in 3 groups: (a) lean subjects with normal intrahepatic triglyceride (IHTG) and glucose tolerance (lean-NL; n = 14), (b) obese subjects with normal IHTG and glucose tolerance (obese-NL; n = 24), and (c) obese subjects with nonalcoholic fatty liver disease (NAFLD) and prediabetes (obese-NAFLD; n = 22).RESULTSInsulin sensitivity progressively decreased and insulin secretion progressively increased from the lean-NL to the obese-NL to the obese-NAFLD groups. Fractional hepatic insulin extraction progressively decreased from the lean-NL to the obese-NL to the obese-NAFLD groups, whereas total hepatic insulin extraction (molar amount removed) was greater in the obese-NL and obese-NAFLD subjects than in the lean-NL subjects. Insulin appearance in the systemic circulation and extrahepatic insulin extraction progressively increased from the lean-NL to the obese-NL to the obese-NAFLD groups. Total hepatic insulin extraction plateaued at high rates of insulin delivery, whereas the relationship between systemic insulin appearance and total extrahepatic extraction was linear.CONCLUSIONHyperinsulinemia after glucose ingestion in obese-NL and obese-NAFLD is due to an increase in insulin secretion, without a decrease in total hepatic or extrahepatic insulin extraction. However, the liver's maximum capacity to remove insulin is limited because of a saturable extraction process. The increase in insulin delivery to the liver and extrahepatic tissues in obese-NAFLD is unable to compensate for the increase in insulin resistance, resulting in impaired glucose homeostasis.TRIAL REGISTRATIONClinicalTrials.gov NCT02706262.FUNDINGNIH grants DK56341 (Nutrition Obesity Research Center), DK052574 (Digestive Disease Research Center), RR024992 (Clinical and Translational Science Award), and T32 DK007120 (a T32 Ruth L. Kirschstein National Research Service Award); the American Diabetes Foundation (1-18-ICTS-119); Janssen Research & Development; and the Pershing Square Foundation.
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Affiliation(s)
- Gordon I. Smith
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | - Mihoko Yoshino
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Monica L. Kearney
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bruce W. Patterson
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bettina Mittendorfer
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Samuel Klein
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
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Tay J, Goss AM, Garvey WT, Lockhart ME, Bush NC, Quon MJ, Fisher G, Gower BA. Race affects the association of obesity measures with insulin sensitivity. Am J Clin Nutr 2020; 111:515-525. [PMID: 31879755 PMCID: PMC7049529 DOI: 10.1093/ajcn/nqz309] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 11/22/2019] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Race differences in body composition and fat distribution may in part explain the differences in insulin sensitivity and the disproportionate burden of type 2 diabetes in African Americans. OBJECTIVE To determine if differences in body composition and fat distribution explain race differences in insulin sensitivity and identify obesity measures that were independently associated with insulin sensitivity. METHODS Participants were 113 lean, overweight, and obese African-American and Caucasian-American adults without diabetes. Skeletal muscle insulin sensitivity was determined using a hyperinsulinemic-euglycemic clamp (SIClamp, insulin rate:120 mU/m2/min). Subcutaneous abdominal adipose tissue (SAAT), intra-abdominal adipose tissue (IAAT), and liver fat were measured by MRI; leg fat, total fat, and lean mass were measured by DXA. RESULTS Race-by-adiposity interactions were significant in cross-sectional analyses utilizing multiple linear regression models for SIClamp (P < 0.05); higher BMI, fat mass, SAAT, leg fat, and liver fat were associated with lower SIClamp in Caucasian Americans but not African Americans. Race-by-IAAT interaction was not significant (P = 0.65). A central fat distribution (SAAT adjusted for leg fat) was associated with lower SIClamp in African Americans (β = -0.45, SE = 0.11, P < 0.001) but not Caucasian Americans (β = -0.42, SE = 0.30, P = 0.17). A peripheral fat distribution (leg fat adjusted for IAAT/SAAT) was associated with a higher SIClamp in African Americans (β = 0.11, SE = 0.05, P = 0.02) but lower SIClamp in Caucasian Americans (β = -0.28, SE = 0.14, P = 0.049). Lean mass was inversely associated with SIClamp in African Americans (β = -0.05, SE = 0.03, P = 0.04) but not Caucasian Americans (β = 0.08, SE = 0.05, P = 0.10) in the model for leg fat. CONCLUSIONS Measures of overall adiposity were more strongly associated with SIClamp in Caucasian Americans, whereas body fat distribution and lean mass showed stronger correlations with SIClamp in African Americans. Insulin sensitivity may have a genetic basis in African Americans that is reflected in the pattern of body fat distribution. These findings suggest a race-specific pathophysiology of insulin resistance, which has implications for the prevention of diabetes and related cardiometabolic diseases.
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Affiliation(s)
- Jeannie Tay
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
- Singapore Institute of Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR), Singapore
- Address correspondence to JT (e-mail: )
| | - Amy M Goss
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - W Timothy Garvey
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mark E Lockhart
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nikki C Bush
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Michael J Quon
- Division of Endocrinology, Department of Medicine, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Gordon Fisher
- Department of Human Studies, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Barbara A Gower
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
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Bergman RN. Origins and History of the Minimal Model of Glucose Regulation. Front Endocrinol (Lausanne) 2020; 11:583016. [PMID: 33658981 PMCID: PMC7917251 DOI: 10.3389/fendo.2020.583016] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 12/22/2020] [Indexed: 01/17/2023] Open
Abstract
It has long been hoped that our understanding of the pathogenesis of diabetes would be helped by the use of mathematical modeling. In 1979 Richard Bergman and Claudio Cobelli worked together to find a "minimal model" based upon experimental data from Bergman's laboratory. Model was chosen as the simplest representation based upon physiology known at the time. The model itself is two quasi-linear differential equations; one representing insulin kinetics in plasma, and a second representing the effects of insulin and glucose itself on restoration of the glucose after perturbation by intravenous injection. Model would only be sufficient if it included a delay in insulin action; that is, insulin had to enter a remote compartment, which was interstitial fluid (ISF). Insulin suppressed endogenous glucose output (by liver) slowly. Delay proved to be due to initial suppression of lipolysis; resultant lowering of free fatty acids reduced liver glucose output. Modeling also demanded that normalization of glucose after injection included an effect of glucose itself on glucose disposal and endogenous glucose production - these effects were termed "glucose effectiveness." Insulin sensitivity was calculated from fitting the model to intravenous glucose tolerance test data; the resulting insulin sensitivity index, SI, was validated with the glucose clamp method in human subjects. Model allowed us to examine the relationship between insulin sensitivity and insulin secretion. Relationship was described by a rectangular hyperbola, such that Insulin Secretion x Insulin Sensitivity = Disposition Index (DI). Latter term represents ability of the pancreatic beta-cells to compensate for insulin resistance due to factors such as obesity, pregnancy, or puberty. DI has a genetic basis, and predicts the onset of Type 2 diabetes. An additional factor was clearance of insulin by the liver. Clearance varies significantly among animal or human populations; using the model, clearance was shown to be lower in African Americans than Whites (adults and children), and may be a factor accounting for greater diabetes prevalence in African Americans. The research outlined in the manuscript emphasizes the powerful approach by which hypothesis testing, experimental studies, and mathematical modeling can work together to explain the pathogenesis of metabolic disease.
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Bergman RN, Piccinini F, Kabir M, Ader M. Novel aspects of the role of the liver in carbohydrate metabolism. Metabolism 2019; 99:119-125. [PMID: 31158368 PMCID: PMC7216693 DOI: 10.1016/j.metabol.2019.05.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/23/2019] [Accepted: 05/25/2019] [Indexed: 01/21/2023]
Abstract
Malfunction of the liver is a central factor in metabolic disease. Glucose production by liver is complex and controlled via indirect mechanisms; insulin regulates adipose tissue lipolysis, and free fatty acids in turn regulate liver glucose output. This latter concept is confirmed by studies in L-Akt-Foxo1 knockout mice. The adipocyte is a likely locus of hepatic insulin resistance. Also, kidneys play a role in regulating glucose production; denervated kidneys abrogate the effect of fat feeding to cause insulin resistance. Glucose itself is an important regulator of liver metabolism ("glucose effectiveness"); after entering liver, glucose is phosphorylated and can be exported as lactate. Using the dynamic glucose/lactate relationship, we have been able to estimate glucose effectiveness in intact animals and human subjects. Families have been identified with a glucokinase regulatory protein defect; modeling demonstrates elevated glucokinase activity. Insulin clearance by liver is highly variable among normal individuals, and is under environmental control: high fat diet reduces clearance by 30%. Liver insulin clearance is significantly lower in African American (AA) adults and children compared to European American participants, accounting for fasting hyperinsulinemia in AA. We hypothesize that reduced hepatic insulin clearance causes peripheral insulin resistance and increased Type 2 diabetes in AA.
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Affiliation(s)
- Richard N Bergman
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States of America.
| | - Francesca Piccinini
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States of America
| | - Morvarid Kabir
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States of America
| | - Marilyn Ader
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States of America
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Bergman RN, Piccinini F, Kabir M, Kolka CM, Ader M. Hypothesis: Role of Reduced Hepatic Insulin Clearance in the Pathogenesis of Type 2 Diabetes. Diabetes 2019; 68:1709-1716. [PMID: 31431441 PMCID: PMC6702636 DOI: 10.2337/db19-0098] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 06/02/2019] [Indexed: 12/19/2022]
Abstract
There is wide variance among individuals in the fraction of insulin cleared by the liver (20% to 80%). Hepatic insulin clearance is 67% lower in African Americans than European Americans. Clearance is also lower in African American children 7-13 years of age. Lower hepatic insulin clearance will result in peripheral hyperinsulinemia: this exacerbates insulin resistance, which stresses the β-cells, possibly resulting in their ultimate failure and onset of type 2 diabetes. We hypothesize that lower insulin clearance can be a primary cause of type 2 diabetes in at-risk individuals.
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Affiliation(s)
- Richard N Bergman
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Francesca Piccinini
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Morvarid Kabir
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Cathryn M Kolka
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Marilyn Ader
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
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Ethnic distinctions in the pathophysiology of type 2 diabetes: a focus on black African-Caribbean populations. Proc Nutr Soc 2019; 79:184-193. [PMID: 31307560 DOI: 10.1017/s0029665119001034] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Type 2 diabetes (T2D) is a global public health priority, particularly for populations of black African-Caribbean ethnicity, who suffer disproportionately high rates of the disease. While the mechanisms underlying the development of T2D are well documented, there is growing evidence describing distinctions among black African-Caribbean populations. In the present paper, we review the evidence describing the impact of black African-Caribbean ethnicity on T2D pathophysiology. Ethnic differences were first recognised through evidence that metabolic syndrome diagnostic criteria fail to detect T2D risk in black populations due to less central obesity and dyslipidaemia. Subsequently more detailed investigations have recognised other mechanistic differences, particularly lower visceral and hepatic fat accumulation and a distinctly hyperinsulinaemic response to glucose stimulation. While epidemiological studies have reported exaggerated insulin resistance in black populations, more detailed and direct measures of insulin sensitivity have provided evidence that insulin sensitivity is not markedly different to other ethnic groups and does not explain the hyperinsulinaemia that is exhibited. These findings lead us to hypothesise that ectopic fat does not play a pivotal role in driving insulin resistance in black populations. Furthermore, we hypothesise that hyperinsulinaemia is driven by lower rates of hepatic insulin clearance rather than heightened insulin resistance and is a primary defect rather than occurring in compensation for insulin resistance. These hypotheses are being investigated in our ongoing South London Diabetes and Ethnicity Phenotyping study, which will enable a more detailed understanding of ethnic distinctions in the pathophysiology of T2D between men of black African and white European ethnicity.
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Ladwa M, Hakim O, Amiel SA, Goff LM. A Systematic Review of Beta Cell Function in Adults of Black African Ethnicity. J Diabetes Res 2019; 2019:7891359. [PMID: 31781667 PMCID: PMC6855028 DOI: 10.1155/2019/7891359] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/16/2019] [Accepted: 08/11/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Understanding ethnic differences in beta cell function has important implications for preventative and therapeutic strategies in populations at high risk of type 2 diabetes (T2D). The existing literature, largely drawn from work in children and adolescents, suggests that beta cell function in black African (BA) populations is upregulated when compared to white Europeans (WE). METHODS A systematic literature search was undertaken in June 2018 to identify comparative studies of beta cell function between adults (>age 18 years) of indigenous/diasporic BA and WE ethnicity. All categories of glucose tolerance and all methodologies of assessing beta cell function in vivo were included. RESULTS 41 studies were identified for inclusion into a qualitative synthesis. The majority were studies in African American populations (n = 30) with normal glucose tolerance (NGT)/nondiabetes (n = 25), using intravenous glucose stimulation techniques (n = 27). There were fewer studies in populations defined as only impaired fasting glucose/impaired glucose tolerance (IFG/IGT) (n = 3) or only T2D (n = 3). Although BA broadly exhibited greater peripheral insulin responses than WE, the relatively small number of studies which measured C-peptide to differentiate between beta cell insulin secretion and hepatic insulin extraction (n = 14) had highly variable findings. In exclusively IGT or T2D cohorts, beta cell insulin secretion was found to be lower in BA compared to WE. CONCLUSIONS There is inconsistent evidence for upregulated beta cell function in BA adults, and they may in fact exhibit greater deficits in insulin secretory function as glucose intolerance develops.
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Affiliation(s)
- M. Ladwa
- Diabetes Research Group, Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - O. Hakim
- Diabetes Research Group, Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - S. A. Amiel
- Diabetes Research Group, Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - L. M. Goff
- Diabetes Research Group, Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
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