Microbiome Individuality and Stability Over Time (MISO)

Microbial derived uremic solutes (p-cresol sulfate, indoxyl sulfate, and phenylacetylglutamine) are present in blood and excreted into the urine. Uremic solutes have high inter-individual variability of unclear etiology, that the investigators hypothesize is due to intestinal microbiome variation and/or dietary variation between people. In this study, the investigators will collect baseline samples on participant's habitual diet. The investigators will then administer a homogenous diet to all participants for 7 days and examine levels of uremic solutes in the urine via 24-hour urine collection during this period. In parallel, the investigators will monitor microbiome composition. The investigators predict that during the period subjects are consuming the same, homogenous diet, their excretion of uremic solutes (p-cresol sulfate, indoxyl sulfate, and phenylacetylglutamine) into the urine will have less inter-individual variation.

Study Overview

• Status: Completed
• Conditions: Diet
• Intervention / Treatment: Other: Standardized diet

Detailed Description

Participants will be asked to eat exactly the same meal for one week and to eat this same meal three times each day. Subjects will be allowed to eat as much of this meal as they want and to eat enough so that they do not lose weight. The food will provide a nutritionally adequate diet, designed by a registered dietitian. Participants will be asked not to eat anything else including candy, snacks, etc. and not to drink anything except water including coffee, tea, sodas, or alcoholic drinks.

Samples will be collected at 5 time points:

2 weeks prior to starting test diet, Baseline (day 1 on diet), day 4 on the diet, day 7 on the diet, 7 days after end of diet.

Samples collected include:

Blood sample Stool sample 24 hr urine collection Diet and Gastrointestinal questionnaires

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Stanford, California, United States, 94305
      • Stanford University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Healthy individuals

Exclusion Criteria:

• pregnancy
• diabetes
• gastrointestinal disease
• use of medications thought by the investigators to have a significant effect on the microbiome

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Uremic solute variability	25% reduction of the coefficient of variation of 24hr urinary excretion of at least 1 of 3 uremic solutes (p-cresol sulfate, indoxyl sulfate or phenylacetylglutamine) measured in mg/day/1.73 during the homogenous diet period as compared to the baseline/habitual diet period.	2 years

Collaborators and Investigators

• Sponsor: Stanford University

Study record dates

Study Major Dates

• Study Start (ACTUAL): August 6, 2018
• Primary Completion (ACTUAL): February 11, 2019
• Study Completion (ACTUAL): February 11, 2019

Study Registration Dates

• First Submitted: February 1, 2021
• First Submitted That Met QC Criteria: February 1, 2021
• First Posted (ACTUAL): February 5, 2021

Study Record Updates

• Last Update Posted (ACTUAL): May 7, 2021
• Last Update Submitted That Met QC Criteria: May 4, 2021
• Last Verified: May 1, 2021

More Information

Terms related to this study

• Other Study ID Numbers: 44718

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No