Dietary Exposure
Conditions
Keywords
Gut microbiota, Trimethylamine N-oxide, L-carnitine supplementation, Oral carnitine challenge test
Brief summary
In this project, the investigators aim to explore the impact of dietary L-carnitine supplementation on the TMAO production capacity of gut microbiota.
Detailed description
Recent studies have established plasma trimethylamine N-oxide (TMAO) levels as a strong, independent risk factor for cardiovascular disease. TMAO is produced by the interaction between gut microflora and ingested L-carnitine from food. Research indicates that both plasma TMAO concentration and the TMAO production capacity of gut microbiota in vegetarians are significantly lower than in omnivores, likely due to the reduced L-carnitine intake in vegetarian diets. This study aims to explore the impact of L-carnitine supplementation on the TMAO production capacity of human gut microbiota and to identify TMAO-producing bacteria within the gut microflora. The study plans to recruit both omnivore and vegetarian volunteers to undergo a one-month L-carnitine supplementation, followed by an evaluation of changes in TMAO production using an oral L-carnitine challenge test, along with gut microbiota assessment. TMAO concentration will be measured using LC-MS/MS, and gut microbiome analysis will be conducted through shotgun metagenome sequencing. Bioinformatic analysis may reveal potential TMAO-producing bacteria. Understanding the changes in TMAO production and gut microbiota composition post-L-carnitine supplementation may enhance our knowledge of the interplay between L-carnitine supplements, TMAO, and gut microflora.
Interventions
DIETARY_SUPPLEMENTL-carnitine supplementation (500 mg per tablet per day, purchased from GNC company)
Sponsors
National Taiwan University Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
All participants received L-carnitine supplementation (500 mg per tablet per day, GNC) for one month. Oral carnitine challenge tests and fecal sampling were conducted both before and after the intervention.
Eligibility
Sex/Gender
ALL
Age
20 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy subjects aged 20 to 65 years old * no usage of antibiotics within one month * no use of carnitine supplement within one month
Exclusion criteria
* having serious GI disorder * medical history of myasthenia gravis * history of diabetes, * history of hyperparathyroidism, * history of chronic kidney disease * history of epilepsy * history of severe anemia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| TMAO level | Before and 1 month after L-carnitine supplementation | plasma and urine TMAO concentrations of oral carnitine challenge test |
| Compositional and functional alterations of gut microbiota | Before and 1 month after L-carnitine supplementation | The compositional and functional changes of gut microbiota will be evaluated by shotgun metagenome sequencing. Taxonomy will be calculated as relative abundance of species-level genome bins (SGBs) and specific bacteria genes will be quantified as Reads Per Kilobase per Million (RPKM). |
Countries
Taiwan
Outcome results
None listed