Investigation on the Efficacy of Oral Carnitine Challenge Test Based on a Gut Microbiota Functional Test

This study seeks to enlist healthy volunteers to form a validation cohort. The purpose is to confirm the observed correlations between the gut microbiome and the capacity to produce trimethylamine N-oxide (TMAO), which will be assessed using the oral carnitine challenge test (OCCT).

Study Overview

• Status: Completed
• Conditions: Healthy; Dysbiosis
• Intervention / Treatment: Diagnostic test: oral carnitine challenge test

Detailed Description

Carnitine, a nutrient widely found in meat, can promote the use of fatty acids by mitochondria to produce energy in the human body. It was previously thought to be beneficial in helping the body consume fat for energy and might be helpful for muscle training or weight loss. However, some human populations have harmful bacteria in their intestines that compete with the body for the use of carnitine. These bacteria metabolize carnitine to produce potentially harmful Trimethylamine N-oxide (TMAO). This might be one of the reasons why long-term consumption of red meat, which is rich in carnitine, is associated with a higher risk of cardiovascular disease. Therefore, understanding the functional state of one's gut microbiota and whether it is suitable to consume foods rich in carnitine can greatly aid in long-term dietary and health planning. In recent years, we have established an oral carnitine challenge test that (OCCT) can distinguish whether the intestinal bacteria in a subject produce a large amount of TMAO in the body. This was published in the Gut journal in 2019 and is expected to provide dietary or nutritional supplement recommendations for personalized nutrition for the test subjects. However, the value of the carnitine challenge test in distinguishing between high TMAO producers and low TMAO producers, and whether it can serve as an effective reference for whether a subject is suitable to consume large amounts of meat or take carnitine supplements, still needs further experimental verification. This study seeks to enlist healthy volunteers to form a validation cohort. The purpose is to confirm the observed correlations between the gut microbiome and the capacity to produce TMAO, which will be assessed using the OCCT.

• Study Type: Observational
• Enrollment (Actual): 91

Contacts and Locations

Study Locations

• Taiwan
  • Taipei, Taiwan
    • National Taiwan University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

Healthy individuals undergoing health examinations at the Health Management Center of National Taiwan University Hospital.

Description

Inclusion Criteria:

• adults aged 20 and above who are willing to participate in the trial.

Exclusion Criteria:

1. Under the age of 20
2. History of gastrointestinal surgery
3. History of malignant tumors
4. Those who have used antibiotics, probiotics, or carnitine supplements within the past month will be excluded
5. Liver cirrhosis
6. End-stage kidney disease

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Trimethylamine N-oxide (TMAO) production capacity measured by oral carnitine challenge test (OCCT)	The area under the curve of TMAO levels under OCCT	at enrollment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlations between the gut microbiome and the capacity to produce TMAO	The gut microbiome indicated microbial genes and taxonomies measured by shotgun metagenome sequencing whereas TMAO producing capacity was measured by OCCT.	at enrollment

Collaborators and Investigators

• Sponsor: National Taiwan University Hospital
• Investigators: Principal Investigator: Ming-Shiang Wu, MD, PhD, National Taiwan University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): June 5, 2019
• Primary Completion (Actual): May 14, 2021
• Study Completion (Actual): June 30, 2022

Study Registration Dates

• First Submitted: December 7, 2023
• First Submitted That Met QC Criteria: December 14, 2023
• First Posted (Actual): December 18, 2023

Study Record Updates

• Last Update Posted (Actual): December 18, 2023
• Last Update Submitted That Met QC Criteria: December 14, 2023
• Last Verified: June 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Dysbiosis
• Other Study ID Numbers: 201906010RINC

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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