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.
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.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
16
Vanderbilt University Medical Center
Nashville, Tennessee, United States
Nutrient Absorption
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.
Time frame: 6 hours
Substrate Oxidation
Oxidation of intraduodenally administered glucose or amino acid will be determined by the amount of 13C recovered from expired air.
Time frame: 6 hours
Gut Hormone Levels
Plasma levels of gut hormones will be measured by standard RIA or ELISA assays
Time frame: 6 hours
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.