Adaptive Mechanisms In GRown up ObeSity Study (AMIGROS)

Study Overview
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Brief Summary
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The investigator recently showed that the glycan-binding adipokine galectin-1 increased during overfeeding and that galectin-1 independently could predict type 2 diabetes. Further, the molecules that induce insulin release in the fasting state when blood glucose is normal remain elusive. It is possible that galectin-1 is involved in adaptive mechanisms in adipose tissue in obese subjects.

Detailed Description
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The investigator will define adaptive mechanisms in adipose tissue associated with galectin-1 in obese insulin-sensitive (Ob-IS) subjects compared with obese insulin-resistant (Ob-IR) subjects and lean healthy controls. Further, the investigator will study molecules secreted from adipose tissue that might trigger insulin secretion when blood glucose is normal. The investigator hypothesizes that Ob-IS subjects keep fatty acid levels normal through an adaptive response in adipose tissue that involves up-regulation of galectin-1 for dampening of immune cell activity and stimulation of lipolysis.

Official Title
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Mechanistic Studies in Human Subcutaneous Adipose Tissue

Conditions
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Obesity, Type 2 Diabetes

Intervention / Treatment
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* Device: Subcutaneous microdialysis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women of age: 40.0 - 70.0 years BMI: 18.0 - 25.0 kg/m2 (lean subjects) and BMI 30.0 - 38.0 kg/m2 (Ob-IS and Ob-IR) Fasting insulin < 9.0 mU/l (lean and Ob-IS subjects) and fasting insulin > 9.0 mU/l (Ob-IR) Fasting glucose < 6.1 mmol/l Body temperature < 37.5°C First-degree relative with known T2D in Ob-IR Weight stable ± 5 kg < 3 months before screening Fluent in Swedish and can follow given instructions Consent given to participate Exclusion Criteria: First-degree relative with known T2D in lean or Ob-IS subjects Alcohol intake > 10 units/week or known high alcohol intake < 10 years back in time Daily use of cigarettes or daily frequent use of smokeless tobacco not enabling the participant to suspend nicotine during a visit at the research center without getting abstinent Regular physical activity corresponding to Saltin-Gimby level 4 Special diet eg Atkins or 5:2 for weight reduction. Vegetarian food accepted if duration > 1 year Impaired fasting glucose (IFG) (venous fasting plasma glucose 6.1-6.9 mmol/l) Type 2 diabetes according to ADA criteria Ongoing or previous ischemic heart disease, eg angina pectoris, unstable angina or previous myocardial infarction treated with platelet inhibitors or non vitamin-K oral anticoagulants Heart failure (NYHA II-IV) or cardiac arrhytmia that needs medical treatment Previous cerebral infarction or transitory ischemic episodes (TIA) treated with platelet inhibitors or other anticoagulants Peripheral arterial insufficiency eg claudication Hypertension >170/105 mmHg at screening or more than one class of drugs for treatment of known hypertension Lipid disorder defined as fasting serum triglycerides > 5.0 mmol/l or serum cholesterol > 7.5 mmol/l Hematologic diseases such as anemia not being substituted (Hb < 130 g/l in males and Hv < 120 g/l in females) or disease causing bleeding disorder Renal failure defined as absolute estimated glomerular filtration rate (eGFRcreatinine) < 60 ml/min/1.73 m2 Hypothyroidism defined as TSH > 4.0 mIE/l and symptoms Liver disease e.g. hepatitis B, cirrhosis or conditions where AST or ALT are > 2 times UNL Systemic inflammatory disease e.g. rheumatoid arthritis, ulcerative cholitis or Chrons disease. Celiac disease, dyspepsia or IBS are excepted Chronic bronchitis or chronic obstructive pulmonary with disease symptoms Previous pancreatitis or other disease in pancreas that needs treatment Migraine elicited by stress Spinal insufficiency causing inconvenience lying in supine position during the study day Drug addiction interfering with the study procedures Psychiatric insufficiency interfering with the study procedures Medication with potential to affect adipose tissue metabolism that can not be stopped 10 days before the study days Treatment with beta-blockers Less than three months from previous use of antibiotics Cancer disease < 5 years since diagnosis Physical examination or laboratory results indicating that participation in the study is inappropriate Pregnancy or intention to be pregnant during the study Shift work > 1 time per week that might interfere with the circadian rhytm Other reasons that causes the PI to believe that participation is inappropriate

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Obese insulin-sensitive subjects (Ob-IS)<br>Obese Insulin Sensitive subjects (BMI > 30 kg/m2, fasting insulin < 9.0 mU/l and fasting plasma glucose < 6.1 mmol/l) undergoing subcutaneous microdialysis, needle biopsy, glucose clamp and MRI. | Device: Subcutaneous microdialysis<br>* Group with Ob-IS participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Ob-IR participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Leans, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1.<br>|
| Obese insulin-resistant subjects (Ob-IR)<br>Obese Insulin Resistant subjects (BMI > 30 kg/m2, fasting insulin > 9.0 mU/l and fasting plasma glucose < 6.1 mmol/l) undergoing subcutaneous microdialysis, needle biopsy, glucose clamp and MRI. | Device: Subcutaneous microdialysis<br>* Group with Ob-IS participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Ob-IR participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Leans, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1.<br>|
| Lean healthy controls (Lean)<br>Lean healthy controls (BMI < 25 kg/m2, fasting insulin < 9.0 mU/l and fasting plasma glucose < 6.1 mmol/l) undergoing subcutaneous microdialysis, needle biopsy, glucose clamp and MRI. | Device: Subcutaneous microdialysis<br>* Group with Ob-IS participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Ob-IR participants, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1. Group with Leans, collection of abdominal subcutaneous interstitial dialysates after an overnight´s fast for later measurements of metabolites and peptides eg galectin-1.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting galectin-1 concentration in subcutaneous interstitial fluid | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting Neuropilin-1 concentration in subcutaneous interstitial fluid | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting serum galectin-1 concentrations | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting serum neuropilin-1 concentrations | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting fatty acid levels in subcutaneous dialysates | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting plasma fatty acid concentrations | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting amino acid profile in subcutaneous dialysates | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Fasting serum amino acid concentrations | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Circulating metabolome including lipoprotein-related parameters measured by Mass Spectrometry | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Circulating lipidome including lipid derivatives measured by Mass Spectrometry | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Peptides identified by Mass Spectrometry in subcutaneous dialysates | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 
| Ectopic lipid accumulation assessed by magnetic resonance imaging in relative measures | Comparison between eligible Ob-IS and Ob-IR subjects < 9 weeks after enrolment | Nine weeks | 
| RNA sequencing results of subcutaneous adipose cells | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Function of immune cells in subcutaneous stromal vascular fraction characterized by Fluorescence Activated Cell Sorting (FACS) | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Activation of insulin signaling proteins in adipose cells assessed by Western blot | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Function of microvascular endothelial cells in subcutaneous stromal vascular fraction | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Messenger RNA expression in whole adipose tissue | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Dysbiosis in faeces assessed by 16S rRNA gene sequencing | Comparison between eligible Ob-IS and Ob-IR subjects < 6 weeks after enrolment | Six weeks | 
| Metabolites in urine including acylcarnitines measured by Mass Spectrometry | Comparison between eligible Ob-IS and Ob-IR subjects < 3 weeks after enrolment | Three weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Adipose cells, Fatty acids, Microdialysis, Stromal vascular fraction, Ectopic lipid accumulation, Fasting hyperinsulinemia, Insulin resistance, Amino acids