The Impact of Bariatric Surgery on Adipocyte Metabolism

The purpose of this study is to understand how daily rhythms of behavior affect the expression of genes in fat cells, and how these daily cycles affect the way fat cells respond to insulin (a hormone that controls blood sugar levels) before and after bariatric surgery.

Study Overview

• Status: Recruiting
• Conditions: Obesity; Metabolic Syndrome
• Intervention / Treatment: Behavioral: Circadian Clock Alignment; Behavioral: Circadian Clock Control

Detailed Description

Bariatric surgery as a means of weight loss has become increasingly popular over the last 10-15 years. In addition to promoting weight loss, bariatric surgery has become increasingly recognized for use in the management of diabetes. Recent studies have indicated that bariatric surgery can result in a marked improvement in insulin sensitivity before long term weight loss is attained. The goal of this project is to delineate the changes in the insulin responsiveness of subcutaneous adipocytes obtained by needle biopsy 2 weeks prior to surgery vs. 12 weeks after bariatric surgery, which could account for improvements in overall insulin sensitivity seen before any long-term sustained weight loss has occurred. The investigators will also examine gene expression in adipocytes (fat cells).

• Study Type: Interventional
• Enrollment (Anticipated): 82
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Erin Hanlon, PhD; Phone Number: (773) 834-5849; Email: ehanlon@bsd.uchicago.edu
• Study Contact Backup: Name: Matthew Brady, PhD; Phone Number: (773) 702-2346; Email: mbrady@bsd.uchicago.edu

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60637
      • Recruiting
      • University of Chicago
      • Contact: Erin Hanlon, PhD; Phone Number: (773) 834-5849; Email: ehanlon@bsd.uchicago.edu
      • Contact: Matthew Brady, PhD; Phone Number: 773-702-2346; Email: mbrady@bsd.uchicago.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Obese Subjects

Inclusion Criteria:

• 18-55 years old
• Female
• BMI greater than 40 kg/m2
• Scheduled for bariatric surgery at the Center for the Surgical Treatment of Obesity at the University of Chicago
• Signed informed consent

Exclusion Criteria:

• Male
• Diagnosed with a systemic illnesses, including heart, renal, liver, or malignant disease
• Uncontrolled hypertension (blood pressure greater than 140 mmHg systolic and 90 mmHg diastolic without medication)
• use of beta blockers
• hemoglobin less than 11.5g/dL
• known allergy to lidocaine
• pregnancy
• lactation
• Subjects will not have undergone surgery, donated a unit of blood, or participated in another clinical study within the last 4 weeks prior to consent.
• Post-menopausal

Non-Obese Subjects

Inclusion Criteria:

• 18-55 years old
• Female
• BMI less than 30 kg/m2
• Signed informed consent

Exclusion Criteria:

• Male
• Diagnosed with a systemic illnesses, including heart, renal, liver, or malignant disease
• Uncontrolled hypertension (blood pressure greater than 140 mmHg systolic and 90 mmHg diastolic without medication)
• use of beta blockers
• hemoglobin less than 11.5g/dL
• known allergy to lidocaine
• pregnancy
• lactation
• Subjects will not have undergone surgery, donated a unit of blood, or participated in another clinical study within the last 4 weeks prior to consent.
• Post-menopausal

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Circadian Clock Alignment - High BMI; Subjects will come to the Sleep Lab three nights before their bariatric surgery procedure for an intervention that will align their central circadian clock. The intervention includes eating meals and snacks at fixed times and having lights off at a specific time at night and lights on at a specific time in the morning.	Behavioral: Circadian Clock Alignment; Use timed lights and meals to align the circadian clock
Active Comparator: Circadian Clock Control - High BMI; Subjects will not come to the Sleep Lab and will live normally at home with no changes to their meal, sleep or wake times.	Behavioral: Circadian Clock Control; No circadian clock alignment
Active Comparator: Circadian Clock Control - Low BMI; Subjects will not come to the Sleep Lab and will live normally at home with no changes to their meal, sleep or wake times.	Behavioral: Circadian Clock Control; No circadian clock alignment

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in insulin sensitivity	Insulin sensitivity will be measured as the by the phosphorylation level of Akt in adipocytes (fat cells) at baseline and 12 weeks post bariatric surgery	12 weeks

Collaborators and Investigators

• Sponsor: University of Chicago
• Investigators: Principal Investigator: Matthew Brady, PhD, University of Chicago

Study record dates

Study Major Dates

• Study Start (Actual): March 26, 2015
• Primary Completion (Anticipated): December 1, 2025
• Study Completion (Anticipated): December 1, 2025

Study Registration Dates

• First Submitted: January 23, 2020
• First Submitted That Met QC Criteria: January 23, 2020
• First Posted (Actual): January 27, 2020

Study Record Updates

• Last Update Posted (Actual): May 10, 2023
• Last Update Submitted That Met QC Criteria: May 8, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Keywords: insulin; gene expression; adipocyte
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Insulin Resistance; Hyperinsulinism; Metabolic Syndrome
• Other Study ID Numbers: IRB14-0984

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No