Insulin Resistance
Conditions
Brief summary
The primary aims of the current study: * using L-carnitine supplementation modulate the level of plasma trimethylamine N-oxide to assess its effect on circulating cytokines related to diabetes and metabolic syndrome; * using simulated night-shift work intervention as a stress factor, explore the effect of circulating metabolites on insulin sensitivity The secondary aim is to evaluate the effect of carnitine supplementation on gut microbiome composition.
Detailed description
Subjects will be randomly divided in two groups: supplemented by L-carnitine 2g/day for 12 weeks, and placebo group receiving leucine in identical gelatine capsules. Subjects who successfully complete the protocol will be divided into four subgroups - two with a changed circadian cycle and two controls (supplemented and placebo). Subgroups with a changed daily cycle will be able to sleep between 8:00 and 17:00 for four consecutive days, while during the night they will stay active in the laboratory. The oral glucose tolerance test (OGTT) will be performed before and after the circadian cycle modification. Glucose levels will be monitored by FreeStyle Libre Sensor. Moreover, the activity of the participants will be monitored by wearable activity trackers. Before supplementation, as well as before circadian cycle modification and after finishing the whole experimental procedure, fasting blood samples will be collected for determination of plasma trimethylamine N-oxide (TMAO), trimethylamine (TMA), carnitine (free and acyl derivatives), protein markers of diabetes and inflammation. Moreover, the stool samples will be collected before and after 12 weeks of supplementation, to determine the composition of the gut microbiome. In addition diet of participants will be monitored.
Interventions
DIETARY_SUPPLEMENTL-carnitine
L-carnitine-L-tartrate
DIETARY_SUPPLEMENTL-leucine
L-leucine
BEHAVIORALChange of the circadian cycle
Reducing sleep at night for four consecutive days (enabling sleep between 8:00 and 17:00)
Sponsors
Poznan University of Physical Education
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
20 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy volunteers, * must be able to swallow tablets
Exclusion criteria
* smokers, * cardiovascular disease * liver disease * kidney disease * gastrointestinal disorders (including stomach ulcers and erosions) * diabetes
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Circulating microbiome metabolites | 13 weeks | Determination of plasma trimethylamine and trimethylamine N-oxide using ultra performance liquid chromatography - tandem mass spectrometer (UPLC-MS/MS) method |
| Circulating carnitine metabolites | 13 weeks | Determination of plasma free, total, and acyl-L-carnitines using ultra performance liquid chromatography - tandem mass spectrometer (UPLC-MS/MS) method |
| Circulating diabetes biomarkers | 13 weeks | insulin, C-peptide, ghrelin, leptin, resistin using enzyme-linked immunosorbent assay |
| Circulating inflammatory biomarkers | 13 weeks | tumor necrosis factor, C-reactive protein using enzyme-linked immunosorbent assay |
| Oral Glucose Tolerance Test | 1 week | The subjects will consume 75 g of glucose solution drink within a 5-minute time frame. The glucose level will be continuously monitored with the FreeStyle Libre Sensor. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| gut microbiome composition | 13 weeks | 16 S rRNA sequencing will be used to analyze the gut microbiome in the stool samples |
Countries
Poland
Outcome results
None listed