The Kidney's Response to Exercise in Heat, and the Impact of Vitamin B3 on This Response

Purpose

The goal of this clinical trial is to learn about the processes occurring in the kidneys while under heat stress in healthy volunteers. The main questions it aims to answer are: - How do the chemicals produced by the body change under conditions of higher versus lower heat stress? - What role does a specific area of the body's metabolism, known as NAD+ metabolism, play in the body's response to heat stress, and can this response be modified by taking vitamin B3?

Conditions

  • Heat Strain
  • Healthy Volunteer Study
  • Kidney Dysfunction

Eligibility

Eligible Ages
Between 18 Years and 45 Years
Eligible Sex
All
Accepts Healthy Volunteers
Yes

Inclusion Criteria

  • Healthy volunteer - Any race - Estimated glomerular filtration rate greater than 90 ml/min/1.73m2 - Urine albumin/creatinine ratio less than 30mg/g - Nonsmoker - No regular dietary supplements, particularly vitamin B3 - Physically fit, defined as having a VO2 max of between 35 and 60mL/kg/min

Exclusion Criteria

  • Medical condition preventing safe participation in exercise during heat - Allergy to Vitamin B3 - Severe food allergies or dietary restrictions that would preclude eating the planned study diet without major modifications

Study Design

Phase
Early Phase 1
Study Type
Interventional
Allocation
Randomized
Intervention Model
Crossover Assignment
Intervention Model Description
There are two phases to this study. The first phase is a dose-response phase evaluating the effect of experimental heat strain on kidney metabolic and stress response. The second phase uses this experimental heat strain at a dose producing kidney metabolic and stress response to conduct a crossover trial investigating how Vitamin B3 impacts the kidney's metabolic and stress response during heat strain.
Primary Purpose
Basic Science
Masking
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)

Arm Groups

ArmDescriptionAssigned Intervention
Experimental
Vitamin B3, then placebo 		Individuals will receive 1000mg oral Vitamin B3 daily for two days leading up to their first exercise session, and oral placebo daily for two days leading up to their second exercise session.
  • Dietary Supplement: Vitamin B3
    1000mg once a day orally for two days, once the day before the exercise session, and once the day of the exercise session.
    Other names:
    • niacinamide
Experimental
Placebo, then vitamin B3 		Individuals will receive 1000mg oral placebo daily for two days leading up to their first exercise session, and oral vitamin B3 daily for two days leading up to their second exercise session.
  • Dietary Supplement: Vitamin B3
    1000mg once a day orally for two days, once the day before the exercise session, and once the day of the exercise session.
    Other names:
    • niacinamide

Recruiting Locations

Boston University
Boston 4930956, Massachusetts 6254926 02215
Contact:
Dustin Allen, PhD
417-693-2182
drallen@bu.edu

More Details

Status
Recruiting
Sponsor
Beth Israel Deaconess Medical Center

Study Contact

Nathan H Raines, MD MPH
703-927-0992
nraines@bidmc.harvard.edu

Detailed Description

To answer these questions, researchers will compare the chemical changes in each participant under progressively higher levels of heat stress, and while taking either vitamin B3 or a placebo. This clinical trial will occur in two stages. Participants may choose participate in stage 1 only, stage 2 only, or both parts of this clinical trial. During stage 1, participants will exercise using a stationary rowing ergometer in a hot and humid environmental chamber for three sessions, each session separated by about a week. - Each session, they will be asked to work out at a progressively higher intensity with climate conditions kept the same in the chamber. - More intense exercise produces greater heat stress, resulting in lower, moderate, and higher levels of heat stress exposure across the three sessions. - Researchers will see how chemicals in the blood and urine, along with physical measurements like heart rate and body temperature, change across these different levels of heat stress. During stage 2, participants will exercise using the same rowing ergometer in the same environmental chamber. They will do this for two sessions, each separated by about a week. - One of the sessions each participant will take vitamin B3, and the other session each participant will take placebo. - Heat stress exposure will be the same each session. - Researchers will again see how chemicals in the blood and urine, along with physical measurements like heart rate and body temperature, differ between sessions with vitamin B3 and sessions with placebo