The Alberta NutrIMM Study - Nutrition and Immunity (NutrIMM)

The Alberta NutrIMM (Nutrition and Immune Function) Study: Establishing the Importance of Diet and Insulin Resistance in Modulating Immune Function in Obesity

This study will investigate the effect of body weight, diet, and high blood sugar levels, under controlled feeding conditions, on immune function in individuals with and without obesity.

This study will be a non-randomized, four-arm parallel group, clinical trial under controlled feeding conditions (4-week nutritional intervention using a North American-type diet). A sample size of n=128 participants will be allocated into one of the following groups:

• Individuals without obesity and normoglycemia (NG) (Lean-NG)
• Individuals with obesity and normoglycemia (Obese-NG)
• Individuals with obesity and glucose intolerance (GI) (Obese-GI)
• Individuals with obesity and type 2 diabetes (T2D) (Obese-T2D)

The following outcomes will be analyzed:

• Immune cell function (ex-vivo cytokine production after stimulation with mitogen and T cell proliferation);
• Immune cell phenotypes;
• Systemic inflammation (C-reactive protein and plasma cytokines);
• Glucose, insulin, glycated hemoglobin (HbA1c), and lipids;
• Fatty acids and phospholipds composition in plasma and red blood cells membrane.

Study Overview

• Status: Completed
• Conditions: Obesity; Diabetes Mellitus, Type 2
• Intervention / Treatment: Other: North American-type diet

Detailed Description

Obesity is associated with several risk factors (for example, high blood sugar, poor insulin response and inflammation) that increase risk of developing cardiovascular disease and T2D. Obesity is also associated with abnormalities in the immune system and an increased risk of infection. Specific components of the diet such, as high dietary intake of fat and sugar, influence not only the development of obesity but also the immune system. It is unknown if the immune abnormalities associated with obesity in humans are due to: 1) excess body fat and/or 2) elevated blood sugar levels, often seen in obesity and/or 3) overall diet quality of an individual (for example high fat and/or high sugar intakes).

The overall aim of this research proposal is to determine if diet or alterations in blood sugar levels independently affect inflammation and immune function in obese subjects. To achieve this goal, three objectives will be pursued: 1) to determine how obesity affects inflammation and immune function; 2) to determine how alterations in blood sugar levels affect inflammation and immune function; 3) to identify specific dietary factors that affect changes in immune function that are related to obesity.

The study will recruit 4 groups of subjects that are similar in age and sex: lean subjects with normal blood sugar levels (NG); obese subjects with normal blood sugar levels (obese-NG); obese subjects who are pre-diabetic (as defined by having high blood sugar levels - but not high enough to be defined as having diabetes; GI); obese subjects who have type 2 diabetes (obese-T2D).

Participants will consume a typical North American/Canadian diet that will maintain their weight for a 4-week time period (all food will be provided for the subjects by the Human Nutrition Clinical Research Unit at the University of Alberta). Immune system markers (inflammation in the blood and the response of immune cells) and cardiovascular disease markers (e.g., blood sugar and insulin) will be compared among the 4 groups of participants before and at the end of the study.

A stool sample will also be collected before and after the diet intervention to look at the effects of weight and blood sugar levels on the type of bacteria in the participants gut as part of a Stool Sub-study. Research has shown that weight and blood sugar levels may affect the type of bacteria in the participants gut, which in turn can affect immune function and health risk. This is not a part of the main study, and the participants stool sample will be analyzed in future research.

By comparing these four groups, the investigators will be able to gain an understanding of the immune complications associated with obesity alone (ie excess body fat) and the relationship between blood sugar levels and diet with immune complications. Thus, this study will identify dietary interventions to counteract the immune abnormalities associated with obesity, which may in turn have implications for affecting the risk of cardiovascular disease and T2D associated with obesity.

• Study Type: Interventional
• Enrollment (Actual): 114
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Edmonton, Alberta, Canada, T6G 2E1
      • University of Alberta

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria

• Age of 18 years to 70 years;
• Body weight stable (± 3%) for at least three months prior to study commencement;
• Body mass index (1) between 18.5 and 24.9 (± 0.5) kg/m2 or (2) between 30 and 50 kg/m2 (± 0.5) kg/m2 or waist circumference >88 cm or > 102 cm for females and males, respectively;

See below for specific group allocation criteria based on glucose, HbA1c, High density lipoprotein cholesterol (HDL-C), and triglycerides.

• Fasting blood glucose levels (mmol/L): < 5.6 (Lean-NG and Obese-NG), 5.6-6.9 (Obese-GI), and ≥ 7.0 (Obese-T2D);
• HbA1c (%): < 5.5 (Lean-NG and Obese-NG), 5.5-6.4 (Obese-GI), and ≥ 6.5 (Obese-T2D);
• Blood Pressure (mmHg): < 130/85 (Lean-NG and Obese-NG), not required for Obese-GI and Obese-T2D;
• Triglycerides (mmol/L): < 1.7 (Lean-NG and Obese-NG), not required for Obese-GI and Obese-T2D;
• HDL-C (mmol/L): ≥ 1.03 for males and ≥ 1.29 for females (Lean-NG and Obese-NG), not required for Obese-GI and Obese-T2D.

Exclusion Criteria

• Current or recent history cardiovascular diseases or events (e.g., ischemic, rheumatic, or congenital heart disease, stroke, peripheral vascular disease, heart failure, familial hypercholesterolemia or other monogenic dyslipidemia), use of cardiac implantable electronic devices;
• Current or recent cancer, including remission, during the last five years;
• Diseases known to affect the immune system, such as infectious, inflammatory, and autoimmune diseases or autoimmune-related or suspected conditions (e.g., T1D, systemic lupus erythematosus, inflammatory bowel disease), except for psoriasis, atopic dermatitis, and rheumatoid arthritis. Continuous use of anti-inflammatory or immunosuppressant drugs and supplements for which washout is not possible, except for medications which participants with obesity could not refrain from (e.g., baby aspirins);
• Renal disorders, endocrine disorders other than T2D (e.g., acromegaly, Addison's disease, Cushing's disease);
• Untreated or uncontrolled thyroid diseases (e.g., Hashimoto's disease, hypothyroidism, hyperthyroidism);
• Known allergy, aversion to any components of the menu, or restricted dietary patterns (e.g., gluten-free diet, vegetarianism, kosher or halal diets) for which accommodations within the menu are not possible;
• Participants under titration of their medication or initiating a new treatment or HbA1c >10.5%;
• Women who are pregnant or plan to become pregnant during the study duration, who are lactating, who have an irregular menstrual cycle or are in perimenopause;
• Regular use of cannabis (e.g. smoking);
• Taking part in any other intervention study that might affect the outcomes of the current study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Individuals without obesity and normoglycemia (NG) (Lean-NG); Those assigned to the Lean-NG group will receive a North American-type diet diet for 4 weeks.	Other: North American-type diet; All groups will receive an isocaloric diet for 4 weeks composed of 48% of energy as carbohydrate, 17% as protein, and 35% as lipid (12.5% of saturated fat, 13% of monounsaturated fat, and 6% of polyunsaturated fat), designed to reflect as closely as possible current macronutrient intake averages in North America/Canada.America/Canada (35% of energy as fat, 12.5% as saturated fat, 13% as monounsaturated fat, 6% as polyunsaturated fat, 48% as carbohydrate, 17% as protein)
Experimental: Individuals with obesity and NG (Obese-NG); Those assigned to the Obese-NG group will receive a North American-type diet diet for 4 weeks.	Other: North American-type diet; All groups will receive an isocaloric diet for 4 weeks composed of 48% of energy as carbohydrate, 17% as protein, and 35% as lipid (12.5% of saturated fat, 13% of monounsaturated fat, and 6% of polyunsaturated fat), designed to reflect as closely as possible current macronutrient intake averages in North America/Canada.America/Canada (35% of energy as fat, 12.5% as saturated fat, 13% as monounsaturated fat, 6% as polyunsaturated fat, 48% as carbohydrate, 17% as protein)
Experimental: Individuals with obesity and glucose intolerance (GI) (Obese-GI); Those assigned to the Obese-GI group will receive a North American-type diet diet for 4 weeks.	Other: North American-type diet; All groups will receive an isocaloric diet for 4 weeks composed of 48% of energy as carbohydrate, 17% as protein, and 35% as lipid (12.5% of saturated fat, 13% of monounsaturated fat, and 6% of polyunsaturated fat), designed to reflect as closely as possible current macronutrient intake averages in North America/Canada.America/Canada (35% of energy as fat, 12.5% as saturated fat, 13% as monounsaturated fat, 6% as polyunsaturated fat, 48% as carbohydrate, 17% as protein)
Experimental: Individuals with obesity and type 2 diabetes (T2D) (Obese-T2D); Those assigned to the Obese-T2D group will receive a North American-type diet diet for 4 weeks.	Other: North American-type diet; All groups will receive an isocaloric diet for 4 weeks composed of 48% of energy as carbohydrate, 17% as protein, and 35% as lipid (12.5% of saturated fat, 13% of monounsaturated fat, and 6% of polyunsaturated fat), designed to reflect as closely as possible current macronutrient intake averages in North America/Canada.America/Canada (35% of energy as fat, 12.5% as saturated fat, 13% as monounsaturated fat, 6% as polyunsaturated fat, 48% as carbohydrate, 17% as protein)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Differences between groups in IL-2 Secretion by Peripheral Blood Mononuclear Cells (PBMC) After Ex-vivo Stimulation with Phytohemagglutinin (PHA) at Week 4	PBMCs will be stimulated with PHA for 48h and IL-2 will be quantified using enzyme-linked immunosorbent assay (ELISA).	Week 4
Differences between groups in circulating C-reactive protein (CRP) at Week 4	CRP will be measured by Alberta Precision Labs using an immunoturbidimetric assay	Week 4

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline in IL-2 Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with Pokeweed Mitogen (PWM) and Phorbol Myristate Acetate and Ionomycin (PMAi), for 48h and IL-2 will be quantified using ELISA	Baseline and Week 4
Change from Baseline in IL-1B Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with Lipopolysaccharides (LPS) and PWM for 48h and PBMCs will be stimulated with PHA, LPS, PWM, and PMAi for 48h and IFN-y will be quantified using ELISA	Baseline and Week 4
Change from Baseline in IFN-y Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with PHA, LPS, PWM, and PMAi for 48h and IFN-y will be quantified using ELISA	Baseline and Week 4
Change from Baseline in TNF-a Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4.	PBMCs will be stimulated with PHA, LPS, PWM, and PMAi for 48h and TNF-a will be quantified using ELISA	Baseline and Week 4
Change from Baseline in IL-10 Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with PHA, LPS, PWM, and PMAi for 48h and IL-10 will be quantified using ELISA	Baseline and Week 4
Change from Baseline in IL-6 Secretion by PBMC After Ex-vivo Stimulation with mitogens at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with PHA, LPS, PWM, PMAi for 48h and IL-6 will be quantified using ELISA	Baseline and Week 4
Change from Baseline in T cell proliferation at Week 4 and Differences Between Groups at Baseline and Week 4	PBMCs will be stimulated with anti-CD3/anti-CD28 for 72h and proliferation will be quantified using alamarBlue dye method, which is a reliable and sensitive assay	Baseline and Week 4
Change from Baseline in T Cells at Week 4 and Differences Between Groups at Baseline and Week 4	Immune cell phenotype of T cells will be determined using immunofluorescence staining for flow cytometry. The following monoclonal antibodies will be used: CD3, CD4, CD8, CD25, CD28, CD45RA, CD45RO, CTLA-4 (CD152), CD192, FoxP3, CD183, CD194, CCR10, CD196, and CD185. Data visualization will be performed in FlowJo software	Baseline and Week 4
Change from Baseline in B Cells at Week 4 and Differences Between Groups at Baseline and Week 4	Immune cell phenotype of B cells will be determined using immunofluorescence staining for flow cytometry. The following monoclonal antibodies will be used: CD19, CD20, ICAM-1 (CD54), CD80, and CD192. Data visualization will be performed in FlowJo software.	Baseline and Week 4
Change from Baseline in Dendritic Cells at Week 4 and Differences Between Groups at Baseline and Week 4	Immune cell phenotype of dendritic cells will be determined using immunofluorescence staining for flow cytometry. The following monoclonal antibodies will be used: CD11c, CD80, CD213, CD273, and HLA-DR. Data visualization will be performed in FlowJo software	Baseline and Week 4
Change from Baseline in Natural Killer Cells at Week 4 and Differences Between Groups at Baseline and Week 4	Immune cell phenotype of T cells will be determined using immunofluorescence staining for flow cytometry. The following monoclonal antibodies will be used: CD3, CD16, and CD56. Data visualization will be performed in FlowJo software	Baseline and Week 4
Change from Baseline in Monocytes at Week 4 and Differences Between Groups at Baseline and Week 4	Immune cell phenotype of Monocytes will be determined using immunofluorescence staining for flow cytometry. The following monoclonal antibodies will be used: CD11c, CD14, ICAM-1 (CD54), CD80, CD86, CD273, and HLA-DR. Data visualization will be performed in FlowJo software	Baseline and Week 4
Change from Baseline in Complete Blood Cell Count and Differential at Week 4 and Differences Between Groups at Baseline and Week 4	Blood count and differential will be analyzed by Alberta Precision Labs in whole blood by fluorescent flow cytometry using a semi-conductor laser and hydrodynamic focusing in dedicated channels using an automated hematology analyzer	Baseline and Week 4
Change from Baseline in Circulating Glucose Levels at Week 4 and Differences Between Groups at Baseline and Week 4	Glucose will be measured by Alberta Precision Labs with an UV testing using an enzymatic reference method with hexokinase	Baseline and Week 4
Change from Baseline in Circulating Insulin Levels at Week 4 and Differences Between Groups at Baseline and Week 4	Insulin will be measured by Alberta Precision Labs using an electrochemiluminescence immunoassay	Baseline and Week 4
Change from Baseline in Circulating Hemoglobin A1c Levels at Week 4 and Differences Between Groups at Baseline and Week 4	HbA1c will be measured by Alberta Precision Labs using a turbidimetric inhibition immunoassay for hemolyzed whole blood	Baseline and Week 4
Change from Baseline in Circulating Triglycerides Levels at Week 4 and Differences Between Groups at Baseline and Week 4	Triglycerides will be measured by Alberta Precision Labs using an enzymatic colorimetric assay	Baseline and Week 4
Change from Baseline in Circulating Total Cholesterol Levels at Week 4 and Differences Between Groups at Baseline and Week 4	Total Cholesterol will be measured by Alberta Precision Labs using an enzymatic colorimetric assay	Baseline and Week 4
Change from Baseline in Circulating Low-Density Lipoprotein Cholesterol Levels at Week 4 and Differences Between Groups at Baseline and Week 4	LDL-C is calculated using the following equation: [Total cholesterol - HDLc - (Triglycerides/2.2)]	Baseline and Week 4
Change from Baseline in Circulating High-Density Lipoprotein Cholesterol Levels at Week 4 and Differences Between Groups at Baseline and Week 4	High-Density Lipoprotein Cholesterol will be measured by Alberta Precision Labs using an enzymatic colorimetric assay	Baseline and Week 4
Change from Baseline in Circulating Non-High Density Lipoprotein Cholesterol Levels at Week 4 and Differences Between Groups at Baseline and Week 4	Non-HDL c is derived from the calculation of total cholesterol minus HDL-c	Baseline and Week 4
Differences Between Groups at Week 4 in Circulating Glucose Levels before and after an Oral Glucose Tolerance Test	Blood will be collected at the following time points after consuming the glucose solution: 0, 30, 60, 90, 120, 150, and 180 minutes. Plasma glucose concentrations will be measured using the hexokinase/glucose-6-phosphate dehydrogenase method using a clinical chemistry analyzer	Week 4
Change from Baseline in Total Lipids Fatty Acids Composition in Plasma and Red Blood Cells at Week 4 and Differences Between Groups at Baseline and Week 4	Proportion of fatty acids will be determined using gas chromatography	Baseline and Week 4
Change from Baseline in Phospholipids Fatty Acids Composition in Red Blood Cells at Week 4 and Differences Between Groups at Baseline and Week 4.	Proportion of fatty acids from phospholipids will be determined using gas chromatography	Baseline and Week 4
Change from Baseline in Phospholipids Classes Quantifications in Red Blood Cells at Week 4 and Differences Between Groups at Baseline and Week 4.	Quantification of phospholipds will be determined by high performance liquid chromatography	Baseline and Week 4
Change from Baseline in IL-6 Concentrations at Week 4 and Differences Between Groups at Baseline and Week 4.	IL-6 will be quantified using a multiplex assay (mesoscale).	Baseline and Week 4
Change from Baseline in TNF-a Concentrations at Week 4 and Differences Between Groups at Baseline and Week 4.	TNF-a will be quantified using a multiplex assay (mesoscale).	Baseline and Week 4

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gut microbiota composition by using DNA Sequencing	We will utilize illumina 16S rRNA sequencing and whole metagenomics sequencing to characterize the fecal microbiota (that will be enriched for large bowel bacteria) of our clinical participants pre- and post-diet intervention, to explore if a typical Canadian diet, induces changes in gut microbiota composition and gene content in obese, insulin resistant, and diabetic subjects. These methods will be used as a majority of microbiota are not currently culturable.	4 weeks
Assess correlations between clinical outcomes and microbiome to identify interactions and microbiome signatures that predict how diet may impact these indicators in obese, insulin resistant, and diabetic subjects.	Assess correlations between clinical outcomes and microbiome configurations to identify mechanistic interactions and microbiome signatures that predict how a typical Canadian diet may impact these indicators in obese, insulin resistant, and diabetic subjects	4 weeks

Collaborators and Investigators

• Sponsor: University of Alberta
• Collaborators: Canadian Institutes of Health Research (CIHR)
• Investigators: Principal Investigator: Caroline Richard, PhD, RD, University of Alberta

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2019
• Primary Completion (Actual): May 16, 2023
• Study Completion (Actual): December 1, 2023

Study Registration Dates

• First Submitted: November 29, 2019
• First Submitted That Met QC Criteria: February 27, 2020
• First Posted (Actual): March 2, 2020

Study Record Updates

• Last Update Posted (Estimated): February 6, 2024
• Last Update Submitted That Met QC Criteria: February 4, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: diabetes; obesity; inflammation; lean
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Diabetes Mellitus; Overnutrition; Nutrition Disorders; Overweight; Body Weight; Diabetes Mellitus, Type 2; Obesity
• Other Study ID Numbers: Pro00085839

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No