What this study is
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.
What's being tested
- Endoscopy biopsy
Intervention · OTHER
Tissue samples will be collected from the jejunum, duodenum, and colon during the subject's standard of care procedure.
- Surgical biopsy
Intervention · OTHER
Biopsy of the liver is standard of care for diagnosing NAFLD. Biopsy of omentum, skeletal muscle and subcutaneous adipose (the latter two tissues taken at the site of trocar placement) will be collected intraoperatively at the time of Roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG).
- Mixed-meal tolerance test
Intervention · OTHER
The mixed meal tolerance test (MMTT) shows how much insulin your body is making after drinking a liquid meal beverage that contains fats, protein and carbohydrates (sugar). Glucose, C-peptide, free fatty acids, triglycerides, incretins, pancreatic polypertide, bile aceis, and fatty acid amides can also be measured. A total of 9 tablespoons of blood is taken over a 255 minute period.
- Excised Liver Tissue Sampling
Intervention · OTHER
Tissue will be collected from the excised liver for research after the diseased liver has been removed as part of the standard of care procedure.
Study details
- Official title
- Physiologic and Functional Adaptations of Insulin Sensitive Tissues After Bariatric Surgery
- Sponsor
- Vanderbilt University Medical Center
- Conditions
- Diabetes · Insulin Resistance · Obesity · Bariatric Surgery Candidate · Roux-en-y Gastric Bypass · Liver Diseases
- Enrolling
- 500 people
- Starts
- 2018-02-13
- Est. completion
- 2028-02
- Record
- View on ClinicalTrials.gov ↗
Who can join
Age 18 Years and overSex ALLHealthy volunteers Not acceptedYou may qualify if
- 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
You can't join if
- Known history of intestinal diseases including, but not limited to, inflammatory bowel disease (e.g. ulcerative colitis, Crohn's disease) and celiac sprue.
- Smoking >7 cigarettes per day
- Malabsorptive syndromes
- Pregnant or breastfeeding Additional exclusion criteria for patients undergoing endoscopy/colonoscopy:; Recent history of malignancy (<5 years ago); Previous lap band surgery; Established renal disease Additional exclusion criteria for patients undergoing bariatric surgery:; Previous lap band, sleeve gastrectomy, or gastric bypass surgery; Recent history of malignancy (< 5 years ago); Established organ dysfunction Additional exclusion criteria for patients undergoing liver transplantation:; Previous lap band, sleeve gastrectomy, or gastric bypass surgery; Alpha 1 anti-trypsin disease, Wilson's disease, viral hepatitis, alcoholic liver disease
Sign in and we'll check these against your records.Full criteria on ClinicalTrials.gov ↗
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Study locations (1)
1 openVanderbilt University Medical Center
Nashville, Tennessee, United States
Study team
Sponsor
Vanderbilt University Medical Center
Study ID 171845
Principal investigator
Charles Flynn, Ph.D.
Vanderbilt University Medical Center
Frequently asked questions
The sponsor hasn't published answers to common questions for this trial.