An interventional study of Bariatric surgery and Stable isotope tracer infusion in Metabolic Dysfunction-Associated Steatotic Liver Disease, Metabolic Dysfunction-Associated Steatohepatitis and Obesity, sponsored by Vanderbilt University Medical Center. Not yet recruiting. Open to participants aged 21 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-08-12.
Sponsored by Vanderbilt University Medical Center · Not applicable, Interventional, and Basic science
This prospective, single-center pilot study will evaluate metabolic flux dysregulation in adults with obesity and suspected or confirmed metabolic dysfunction-associated steatotic liver disease (MASLD) who are scheduled for protocol-eligible bariatric surgery at Vanderbilt University Medical Center. Participants will undergo research assessments before surgery, during the planned bariatric surgery encounter, and approximately 6 months after surgery. The study uses non-radioactive stable isotope tracer infusions, serial blood sampling, abdominal MRI/MRE, and research tissue specimens collected only during clinically planned bariatric surgery to quantify hepatic and extrahepatic metabolic fluxes. The primary objective is to determine how hepatic citric acid cycle flux and related metabolic pathways change after bariatric surgery and how these metabolic measures relate to liver fat, liver stiffness, and biopsy-graded MASLD/MASH severity.
MASLD and its progressive form MASH are associated with obesity, insulin resistance, altered hepatic substrate delivery, and changes in mitochondrial metabolism. However, the direction and significance of hepatic citric acid cycle flux changes in human MASLD remain unresolved. This study will apply in vivo metabolic flux analysis using non-radioactive stable isotope tracers to quantify hepatic and extrahepatic metabolic pathway activity in bariatric surgery participants before and after surgery.
Participants will complete three study timepoints. Approximately one week before surgery, participants will undergo fasting physical measurements, questionnaires, research blood collection, and abdominal MRI/MRE to quantify liver fat and stiffness. On the day of surgery, participants will receive intravenous infusions of [¹³C₃]lactate, [6,6-²H₂]-D-glucose, and [9,9-²H₂]palmitate for approximately 120 minutes with serial blood collection. During the clinically planned bariatric surgery, research tissue specimens may be collected from liver, omentum, subcutaneous adipose tissue, and skeletal muscle only if the surgeon determines collection can be performed safely without interfering with clinical care. Approximately 6 months after surgery, participants will repeat fasting physical measurements, questionnaires, MRI/MRE, stable isotope tracer infusion, and blood collection; no follow-up tissue biopsies will be collected.
Isotope enrichment patterns in plasma metabolites and tissue metabolites will be analyzed by mass spectrometry and modeled using metabolic flux analysis software to estimate hepatic citric acid cycle flux, gluconeogenesis, glucose turnover, free fatty acid turnover, lactate turnover, and selected extrahepatic metabolic fluxes. Liver fat and stiffness will be assessed by MRI/MRE, and intraoperative liver tissue will be scored for MASLD/MASH features using established histologic criteria.
11,522 studies on the registry are indexed under Obesity; 2,033 are open to participants now.
This study's planned enrollment of 20 is below the median of 67 across 9,006 interventional studies indexed under Obesity.
Browse Obesity studies →Vanderbilt University Medical Center is the lead sponsor of 833 studies on the registry; 155 are open to participants now.
Of its 125 completed or terminated interventional studies of FDA-regulated products, 92 (74%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
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The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adults scheduled and clinically cleared for protocol-eligible bariatric surgery at VUMC will undergo research MRI/MRE, blood collection, non-radioactive stable isotope tracer infusions, and intraoperative research tissue collection during planned bariatric surgery, followed by repeat noninvasive metabolic assessment approximately 6 months after surgery.
Procedure: Bariatric surgery · Other: Stable isotope tracer infusion · Diagnostic Test: MRI/MRE · Procedure: Research tissue collection during planned bariatric surgery
Clinically indicated bariatric surgery, such as Roux-en-Y gastric bypass or sleeve gastrectomy, performed as part of standard clinical care.
Also known as: Roux-en-Y-gastric byass, sleeve gastrectomey
Intravenous non-radioactive stable isotope tracers administered for research measurement of metabolic flux: \[¹³C₃\]lactate, \[6,6-²H₂\]-D-glucose, and \[9,9-²H₂\]palmitate.
Abdominal MRI proton density fat fraction and magnetic resonance elastography to assess hepatic fat and stiffness before surgery and approximately 6 months after surgery.
Also known as: magnetic resonance imaging, magnetic resonance elastography
Liver, omentum, subcutaneous adipose tissue, and skeletal muscle specimens collected only during clinically planned bariatric surgery and only if safe in the surgeon's judgment.
Change in hepatic citric acid cycle flux after bariatric surgery
Change in hepatic citric acid cycle flux estimated from stable isotope enrichment patterns, including \[¹³C₃\]lactate-based measurements, before bariatric surgery and approximately 6 months after surgery.
Time frame: Baseline/day of surgery to approximately 6 months post-surgery
Change in hepatic gluconeogenic flux
Estimated from plasma glucose isotope enrichment and metabolic flux modeling
Time frame: Baseline/day of surgery to ~6 months
Change in endogenous glucose production
Estimated using \[6,6-²H₂\]-D-glucose tracer dilution
Time frame: Baseline/day of surgery to ~6 months
Change in free fatty acid turnover
Estimated using \[9,9-²H₂\]palmitate tracer dilution
Time frame: Baseline/day of surgery to ~6 months
Change in lactate turnover / lactate-related flux
Estimated using stable isotope enrichment patterns
Time frame: Baseline/day of surgery to ~6 months
Liver fat by MRI-PDFF
Hepatic fat fraction quantified by MRI-PDFF
Time frame: Baseline to ~6 months
Liver stiffness by MRE
Liver stiffness quantified by magnetic resonance elastography
Time frame: Baseline to ~6 months
Histologic MASLD/MASH severity
Liver biopsy scored for steatosis, inflammation, ballooning, fibrosis, and MASLD activity score
Time frame: Intraoperative baseline only
Extrahepatic metabolic fluxes
Metabolic fluxes in skeletal muscle, omentum, and subcutaneous adipose tissue estimated from intraoperative tissue specimens
Time frame: Intraoperative baseline only
Serum inflammatory markers
Research measurement of inflammatory markers including CRP, cytokines, adhesion molecules, and related biomarkers
Time frame: Baseline/day of surgery; possibly ~6 months if collected
Metabolic hormone profile
Insulin, leptin, C-peptide, GLP-1, GIP, PYY, ghrelin
Time frame: Baseline/day of surgery; possibly ~6 months if collected
Bile acid profile
Bile acids measured by LC-IM-MS
Time frame: Baseline/day of surgery; possibly ~6 months if collected
No study locations are listed for this record.
Plan to share: Yes — De-identified or coded individual-level data and biospecimens may be shared for future research only as permitted by the informed consent document, IRB approval, institutional policy, data-use agreements, and applicable privacy protections. No direct identifiers will be included in publications, presentations, reports, or shared datasets.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: Data will be available within one year after study end.
No publications or documents are linked to this record.
Start is estimated for Oct 2026; primary completion for Sep 2029, 35 months later.
Of 3,680 non-industry interventional studies with no phase under Obesity, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 43. This study's planned 35 months is above that.
Counting every sponsor, half of 3,843 studies reached it within 22 months; a quarter within 10 and three quarters within 42.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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