The Effect of Vitamin B3 on Substrate Metabolism, Insulin Sensitivity, and Body Composition in Obese Men

Study Overview
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Brief Summary
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In animals, treatment with vitamin B3 improved insulin sensitivity and substrate metabolism. It is currently not know if vitamin B3 has the same positive effects in humans. In the current study the effect of a 3 month treatment with vitamin B3 on insulin sensitivity and substrate metabolism in obese men will be investigated.

Official Title
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The Effect of Nicotinamide Ribose (NR) on Substrate Metabolism, Insulin Sensitivity, and Body Composition in Obese Men - a Randomized, Placebo Controlled Clinical Trial

Conditions
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Obese

Intervention / Treatment
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* Dietary Supplement: Nicotinamide riboside (NIAGEN TM, ChromaDex, CA, USA )
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: written signed consent male BMI>30 kg/(m2) age: 40-70 no medication non-smoker Exclusion Criteria: endocrine disease other severe disease high daily activity level (>30 min / day)

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

Sexes Eligible for Study
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Male

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br>lime tablets | Dietary Supplement: Placebo<br> <br> |
| Experimental: Nicotinamide riboside (NR, Vit B3)<br>NIAGEN (ChromaDex) 1 g x 2 orally per day | Dietary Supplement: Nicotinamide riboside (NIAGEN TM, ChromaDex, CA, USA )<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin sensitivity | determined by a hyperinsulineamic clamp | Change from baseline in insulin sensitivity at 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Substrate metabolism | measured by indirect calorimetry | Change from baseline in substrate metabolism at 3 months | 
| body composition | measured by DEXA scan | Change from baseline in body composition at 3 months | 
| Activation of satellite cells | measured by immunohistochemestry | Change from baseline in activation of satellite cells at 3 months | 
| lipid accumulation in liver and skeletal muscle tissue | determined by MR-spectroscopy | Change from baseline in liver and muscle lipid content at 3 months | 
| glucose turnover | determined by glucose tracer techniques | Change from baseline in glucose turnover at 3 months | 
| insulin signalling in skeletal muscle and adipose tissue biopsies | western blotting | Change from baseline in insulin signaling at 3 months | 
| Palmitate turnover | determined by palmitate tracer techniques | Change from baseline in palmitate turnover at 3 months | 
| Gut microbiota | Intestinal bacteria composition by whole genome sequencing | Change from baseline in composition of gut microbiota at 3 months | 
| Incretin hormone secretion | Determined by measurement of incretin homones during an oral glucose tolerance test (OGTT) | Change from baseline in incretion hormone secretion at 3 months |