Studies tissue samples from people with obesity and diabetes after bariatric surgery
Collects tissue and blood samples from adults with obesity or diabetes, some having bariatric surgery.
Plain-language title generated from the registry record
Registry title: Physiologic and Functional Adaptations of Insulin Sensitive Tissues
Key facts
- Where
- Nashville, United StatesSee the site
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults scheduled for an upper endoscopy, a colonoscopy, weight-loss (bariatric) surgery or a liver transplant at Vanderbilt University Medical Center. Tissue and blood samples are taken during these procedures.
- Age
- 18 years or older
- Sex
- All sexes can join
- Disease stage
- For weight-loss surgery: obesity with BMI 40 kg/m2 or more, or BMI 35 kg/m2 or more plus one other condition (type 2 diabetes, fatty liver disease, high blood pressure, heart disease or high blood fats). For liver transplant: nonalcoholic liver disease or nonalcoholic steatohepatitis.
- Earlier treatment
- People with a previous lap band, sleeve gastrectomy or gastric bypass cannot join the surgery and liver transplant groups.
Main reasons for not taking part
- Known bowel disease such as ulcerative colitis, Crohn's disease or celiac sprue
- Smoking more than 7 cigarettes per day
- Malabsorptive syndromes
- Pregnant or breastfeeding
- Cancer in the last 5 years (endoscopy and bariatric surgery groups)
Read by machine on 12 November 2026.
Where in United States
- Vanderbilt University Medical CenterNashville, United StatesNo longer taking part
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorTrial details
- Who runs it
- Vanderbilt University Medical Center
- Trial code
- NCT03407833
- Record updated
- 18 December 2025
- Original description
The long-term goal is to understand the mechanisms of intestinal nutrient sensing and signal relays to insulin sensitive tissues (adipose, skeletal muscle, liver) in humans. The investigators hypothesize that human tissue biopsies (from obese surgery and non-surgery subjects as well as lean controls) can be used to understand the molecular mechanisms underlying intestinal nutrient sensing and signal relay in humans. The investigator will obtain tissue specimens from patients during scheduled upper endoscopies, colonoscopies and scheduled metabolic and bariatric surgeries or liver transplantation. A blood sample (4mL) will be obtained concurrent with these procedures. From metabolic and bariatric surgery subjects blood and tissues (liver, adipose, small intestine, omentum, skeletal muscle) can be collected at the time of surgery. From liver transplantation patients, excised liver tissue will be collected. Stool can be obtained preoperatively and at various time points after surgery. Some bariatric surgery subjects will participate in a mixed-meal tolerance test at their pre-operative visit and several post-operative visits to compare the whole-body metabolic alterations following bariatric procedures.Read full original descriptionShow less
Physiologic and Functional Adaptations of Insulin Sensitive Tissues After Bariatric Surgery
The long-term goal is to understand the mechanisms of intestinal nutrient sensing and signal relays to insulin sensitive tissues (adipose, skeletal muscle, liver) in humans. The investigators hypothesize that human tissue biopsies (from obese surgery and non-surgery subjects as well as lean controls) can be used to understand the molecular mechanisms underlying intestinal nutrient sensing and signal relay in humans. The investigator will obtain tissue specimens from patients during scheduled upper endoscopies, colonoscopies and scheduled metabolic and bariatric surgeries or liver transplantation. A blood sample (4mL) will be obtained concurrent with these procedures. From metabolic and bariatric surgery subjects blood and tissues (liver, adipose, small intestine, omentum, skeletal muscle) can be collected at the time of surgery. From liver transplantation patients, excised liver tissue will be collected. Stool can be obtained preoperatively and at various time points after surgery. Some bariatric surgery subjects will participate in a mixed-meal tolerance test at their pre-operative visit and several post-operative visits to compare the whole-body metabolic alterations following bariatric procedures.
Inclusion: Scheduled for upper endoscopy, colonoscopy or metabolic and bariatric surgery, or liver transplantation at Vanderbilt University Medical Center; Additional inclusion criteria for individuals scheduled for metabolic and bariatric surgery: Obese, ≥ 40 kg/m2 or ≥ 35 kg/m2 + one comorbidity (type 2 diabetes [fasting blood glucose ≥ 120 mg/dL; HbA1C ≥ 6.5%]; fatty liver disease, hypertension, cardiovascular disease, hyperlipidemia); Additional inclusion criteria for individuals scheduled for liver transplantation: diagnosis of nonalcoholic liver disease or nonalcoholic steatohepatitis.
Exclusion: Previous lap band surgery; Previous lap band, sleeve gastrectomy, or gastric bypass surgery; Established organ dysfunction; Additional exclusion criteria for patients undergoing liver transplantation:; Previous lap band, sleeve gastrectomy, or gastric bypass surgery; Known history of intestinal diseases including, but not limited to, inflammatory bowel disease (e.g. ulcerative colitis, Crohn's disease) and celiac sprue; Malabsorptive syndromes; Established renal disease; Additional exclusion criteria for patients undergoing bariatric surgery:; Alpha 1 anti-trypsin disease, Wilson's disease, viral hepatitis, alcoholic liver disease; Recent history of malignancy (<5 years ago); Recent history of malignancy (< 5 years ago); Smoking >7 cigarettes per day; Pregnant or breastfeeding; Additional exclusion criteria for patients undergoing endoscopy/colonoscopy:.