Clinical trial NCT03188835: Effects of Fructose/Glucose-rich Diet on Brown Fat in Healthy Subjects (GB7)
Official title: Brown Fat Energy Metabolism During Cold Exposure: Effects of Fructose- or Glucose-rich Diet in Healthy Subjects
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Type2 Diabetes
Lead sponsor: Université de Sherbrooke
Sponsor class: OTHER
Collaborators: name: McMaster University
name: University of Ottawa
First posted: 2017-06-15
Enrollment: 15
Sex: MALE
Minimum age (years): 20
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Activating brown and beige adipose tissue (herein described as BAT) has been recently recognized as a potential means to increase energy expenditure and lower blood glucose, however, BAT activity appears to be reduced with obesity, aging or Type 2 Diabetes (T2D). BAT has the unique capability to burn large amounts of sugar and fat and effectively dissipate this energy as heat due to the expression of uncoupling protein 1 (UCP1) which is controlled by a thermogenic gene program of transcription factors, co-activators and protein kinases. Thus, enhancing the thermogenic gene program may be beneficial for treating obesity and T2D. Despite the importance of BAT in regulating metabolism our understanding of the factors which suppress its metabolic activity with obesity, aging and T2D are largely unknown. Recently, it was shown that peripheral serotonin, which is regulated by the tryptophan hydroxylase 1 (Tph1), is a negative regulator of BAT metabolic activity. In addition to serotonin, other studies have indicated that pro-inflammatory stimuli may also inhibit BAT metabolic activity. These data suggest that reduced activation of BAT may be due to increases in peripheral serotonin and inflammation. Importantly, the gut microbiome has recently been recognized as an important regulator of serotonin and inflammatory pathways suggesting the observed effects of the microbiome on obesity, T2D may be mediated in part through reductions in BAT activity.

One mechanism by which the environment may impact BAT activity and the thermogenic gene program over the last 3 decades involves changes in our food supply as result of changes in agricultural production (chlorpyrifos, glyphosphate) and the addition of food additives (fructose). These agents have been reported to alter inflammation, serotonin metabolism and the gut microbiome indicating a potential bimodal (direct and indirect via the microbiome) mechanism by which they may alter the thermogenic gene program and contribute to chronic metabolic disease. Thus, our overarching hypothesis is that environmental agents and additives related to food production may contribute to the reduced metabolic activity of BAT. The objective is to identify and characterize how food production agents and additives reduce the metabolic activity of BAT.

Detailed description: Each subject will follow 3 metabolic studies (A, B and C), each lasting 7.5h which includes a 3h acute cold exposure.

These studies will be almost identical: same perfusion of tracers, same number of Positron Emission Tomography (PET) acquisitions and same number of Magnetic Resonance Imaging (MRI) associated with Magnetic Resonance Spectroscopy (MRS) acquisitions .

The difference will be in the diet ingested by the subjects two weeks before each metabolic study: during protocol A, the subjects will follow an isocaloric diet; during protocol B, the subjects will follow the same isocaloric diet supplemented with a daily beverage containing +25% of energy intake from fructose; and during protocol C, the subjects will follow the same isocaloric diet supplemented with a daily beverage containing +25% of energy intake from glucose.

Stool samples will be collected for each metabolic study for microbiome flora and metabolites.

Eligibility criteria: Inclusion Criteria:

* Healthy subjects: subjects with normal glucose tolerance determined according to an oral glucose tolerance test and with a BMI \< 27 kg/m2 without first degree of familial history of type 2 diabetes (parents, siblings).

Exclusion Criteria:

1. Plasma triglycerides \> 5.0 mmol/L at fasting;
2. More than 2 alcohol consumption per day;
3. More than 1 cigarette per day;
4. History of total cholesterol level \> 7 mmol/L, of cardiovascular disease, hypertensive crisis;
5. Treatment with fibrates, thiazolidinedione, insulin, beta-blockers or other drugs with effects on insulin resistance or lipid metabolism (exception for anti-hypertensive drugs, statins or metformin);
6. Presence of a non-controlled thyroid disease, renal or hepatic disease, history of pancreatitis, bleeding diatheses, cardiovascular disease or any other serious medical conditions;
7. History of serious gastrointestinal disorders (malabsorption, peptic ulcer, gastroesophageal reflux having required a surgery, etc.);
8. Presence of a pacemaker;
9. Have undergone of PET study or CT scan in the past year;
10. Chronic administration of any medication;

Primary outcomes:
measure: Microbiome flora
timeFrame: 4 months
measure: Microbiome metabolites
timeFrame: 4 months
measure: BAT oxidative metabolism
timeFrame: 4 months
measure: BAT triglyceride content
timeFrame: 4 months
Secondary outcomes:
measure: BAT blood flow
timeFrame: 4 months
measure: BAT net glucose uptake
timeFrame: 4 months
measure: Whole-body glucose partitioning
timeFrame: 4 months
measure: BAT volume of metabolic activity
timeFrame: 4 months
measure: metabolites appearance rate
timeFrame: 12 months
measure: energy metabolism (whole body production)
timeFrame: 4 months
measure: hormonal responses
timeFrame: 12 months
Other outcomes:
Locations:
city: Sherbrooke
country: Canada
facility: Centre de recherche du CHUS
state: Quebec
Study officials:
affiliation: Université de Sherbrooke
name: André C. Carpentier
role: PRINCIPAL_INVESTIGATOR
References:
citation: Richard G, Blondin DP, Syed SA, Rossi L, Fontes ME, Fortin M, Phoenix S, Frisch F, Dubreuil S, Guerin B, Turcotte EE, Lepage M, Surette MG, Schertzer JD, Steinberg GR, Morrison KM, Carpentier AC. High-fructose feeding suppresses cold-stimulated brown adipose tissue glucose uptake independently of changes in thermogenesis and the gut microbiome. Cell Rep Med. 2022 Sep 20;3(9):100742. doi: 10.1016/j.xcrm.2022.100742.