The Effect of LCFA on Nutrient Absorption
Conditions
Keywords
Nutrient absorption, Duodenal feeding tube, Gut-brain-gut axis
Brief summary
Preliminary studies in humans suggest that the presence of lipids in the gut can modify glucose absorption. The overall hypothesis of this proposal is that long chain fatty acid sensing in the duodenum has a significant role in modifying nutrient (glucose and amino acid) absorption from the GI tract through a gut-brain-gut axis.
Detailed description
The investigator will conduct a study in 20 lean (BMI = 19-27 kg/m2) subjects involving intravenous (IV) and intraduodenal (ID) infusions of glucose tracers or amino acid tracers and measurement of tracer rate of appearance in the plasma. An ID infusion of LCFA will allow the investigators to determine if LCFA can alter nutrient absorption and glucose and amino acid metabolism. Benzocaine will be added to the ID infusion of LCFA to inhibit nerve terminals in the duodenum thereby preventing gut-brain communication. Plasma levels of glucose and amino acid tracers, glucose oxidation (13CO2 breath test), gut hormones (CCK, GIP, PYY, GLP-1, ghrelin), and bioactive lipids (N-acyl phosphatidylethanolamines, NAPEs) will be measured during all infusion periods.
Interventions
DRUGBenzocaine Infusion into Duodenum
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Vanderbilt University Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* BMI = 19-27 kg/m2 * 30-55 years of age
Exclusion criteria
* Contraindication for nasal tube placement (e.g. deviated septum, prior upper gastrointestinal bleed, or history of easy bleeding) * Prior gastric or intestinal surgery or pancreas resection * Females with a positive pregnancy test * Known history of intestinal diseases including (but not limited to) inflammatory bowel disease (e.g. ulcerative colitis, Crohn's disease), celiac sprue, Barrett's esophagus * Type 1 or type 2 diabetes * Gastroenteritis (diarrhea and/or vomiting) or constipation within the past week
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Nutrient Absorption | 6 hours | Stable isotope tracers (glucose or amino acid) will be administered intravenously (IV) and intraduodenally (ID) and tracer rate of appearance in the plasma will be measured. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Substrate Oxidation | 6 hours | Oxidation of intraduodenally administered glucose or amino acid will be determined by the amount of 13C recovered from expired air. |
| Gut Hormone Levels | 6 hours | Plasma levels of gut hormones will be measured by standard RIA or ELISA assays |
Other
| Measure | Time frame | Description |
|---|---|---|
| Bioactive Lipids | 6 hours | Plasma levels of N-acyl phosphatidylethanolamines (NAPES)will be measured by LC-MS |
Countries
United States
Outcome results
None listed