NCT03578887

Brief Summary

Patients and clinicians need better options to prevent the weight regain that almost universally follows a weight loss intervention. In lay terms, a new, higher "set point" seems to occur after people gain weight. Evidence from some research studies reinforces these observations, showing that processes of energy homeostasis vigorously defend the higher level of adiposity for years, if not permanently. Only bariatric surgery appears to "re-set" to a lower level of adiposity. No clear mechanism has been elucidated to date that explains these phenomena. The current proposal endeavors to address this crucial scientific gap by translating preclinical data into human studies testing novel mechanistic hypotheses. Prior studies in rodents show that a high-fat diet causes inflammation and a cellular response, known as gliosis, within hypothalamic regions regulating energy balance and glucose homeostasis. Evidence further suggests that gliosis might play a pathogenic role in obesity and type 2 diabetes mellitus (T2D) because its development precedes weight gain and impaired glucose homeostasis and its inhibition improves metabolic health. Importantly, gliosis is detectable in mice and humans by magnetic resonance imaging (MRI). Using MRI, the investigators discovered the first evidence of gliosis in obese humans and went on to show associations of gliosis with insulin resistance in humans, independent of the level of adiposity. New findings suggest that people with T2D have more extensive gliosis than is seen in nondiabetic obese subjects. Further findings reveal that gliosis improves, but is not completely reversed, 8 mo. after Roux-en-Y gastric bypass (RYGB) surgery in T2D patients. It remains unknown whether gliosis improves similarly when weight loss occurs by lifestyle change or if the efficacy and durability of weight loss via bariatric surgery is partially explained by its ability to reverse gliosis via an as yet unknown mechanism of action. We therefore propose three studies in humans to discover 1) if hypothalamic gliosis is reversed by a standard behavioral weight loss intervention, 2) if the extent of gliosis predicts successful weight loss during, or weight regain after, behavioral weight loss, and 3) the time course of improvement in gliosis after RYGB and the relation of its improvement to the short- and long-term efficacy of RYGB. Future research would define dietary, environmental, or other risk factors for the development of hypothalamic gliosis in humans. Achieving a better understanding of the role of the brain in obesity and its treatment could open new avenues for research, intervention, and prevention.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
112

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started Jun 2019

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 25, 2018

Completed
11 days until next milestone

First Posted

Study publicly available on registry

July 6, 2018

Completed
11 months until next milestone

Study Start

First participant enrolled

June 1, 2019

Completed
5.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 30, 2024

Completed
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

June 30, 2025

Completed
28 days until next milestone

Results Posted

Study results publicly available

July 28, 2025

Completed
Last Updated

September 4, 2025

Status Verified

August 1, 2025

Enrollment Period

5.1 years

First QC Date

June 25, 2018

Results QC Date

June 26, 2025

Last Update Submit

August 22, 2025

Conditions

Keywords

Obesity, Gliosis, Weight-Loss, Roux-en-Y Gastric Bypass, Type 2 Diabetes Mellitus

Outcome Measures

Primary Outcomes (2)

  • Percent Change in Weight From Baseline

    During 6 Month Behavioral Weight Loss Program

  • Weight Regain

    Change in Weight (kg) during 12 month follow-up period

    During 12-Month Follow-Up After Intervention

Study Arms (3)

Lifestyle Cohort

ACTIVE COMPARATOR

Participants Undergoing Behavioral Weight Loss Program

Behavioral: Behavioral Weight Loss Program

Surgical Cohort

ACTIVE COMPARATOR

Participants Scheduled for Roux-en-Y Gastric Bypass Surgery

Procedure: Roux-en-Y Gastric Bypass or Sleeve Gastrectomy

Healthy Weight Control Cohort

NO INTERVENTION

Healthy Weight Controls With No Intervention

Interventions

Behavioral Weight Loss Program is a modified version of the Diabetes Prevention Program (DPP).

Lifestyle Cohort

Subjects undergoing Roux-en-Y Gastric Bypass or Sleeve Gastrectomy with their own surgical team

Surgical Cohort

Eligibility Criteria

Age25 Years - 64 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Aged 25-64 years
  • Behavioral Weight Loss (BWL) \& Surgical Weight Loss (SWL) (Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy): BMI 30- \<56 kg/m²
  • RYGB and Sleeve Gastrectomy: eligible for RYGB or Sleeve Gastrectomy and not undergoing revision or reoperation
  • Healthy Weight Controls (HWC): BMI 18.5-24.9 kg/m²

You may not qualify if:

  • Poorly controlled hypertension or coronary artery disease, or chronic disease (e.g. cancer, multiple sclerosis, autoimmune disease, rheumatic disease) Blood Pressure \> 160/100 mmHG Heart Rate \> 110 bpm
  • Chronic kidney disease (GFR \<60 mL/min/1.73 m2),
  • Presence of cirrhosis (Nonalcoholic Fatty Liver Disease (NALFD)/Nonalcoholic Steatohepatitis (NASH) are acceptable),
  • Previous or planned (during the study period) obesity treatment with surgery (planned surgery ok for the SWL group) or a weight loss device. However, the following are allowed: (1) liposuction and/or abdominoplasty, if performed \> 1 year before screening, (2) lap banding, if the band has been removed \> 1 year before screening, (3) intragastric balloon, if the balloon has been removed \> 1 year before screening or (4) duodenal-jejunal bypass sleeve, if the sleeve has been removed \> 1 year before screening,
  • A1c \> 8.5% in Bariatric group; A1c ≥ 6.5% for BWL and HWC groups,
  • Current use of insulin (insulin ok for Surgical Weight Loss group, also called SWL), DPP-4 inhibitors, thiazolidinediones or medications known to alter metabolic function (e.g. atypical antipsychotics, corticosteroids),
  • Pregnancy or breastfeeding,
  • MRI contraindications (e.g. implanted metal, claustrophobia), or unable to have MRI or fit in MRI scanner
  • Current smoking/daily use of nicotine containing products (cigarettes, e-cigarettes, vaping or other nicotine containing products) or heavy alcohol use,
  • Weight \>450 pounds (iDXA limit),
  • Weight-reduced from lifetime maximum weight by \>16%,
  • Weight not stable over past 3 months (±10%),
  • T2D (for BWL or HWC),
  • Inability to participate in a weight loss program (BWL)
  • History of eating disorder or current eating disorder, currently enrolled in a weight loss program (ok for the SWL group provided weight stability and lifetime weight-reduced maximum conditions are met) or taking medications to lose weight
  • +2 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Washington - South Lake Union

Seattle, Washington, 98109, United States

Location

MeSH Terms

Conditions

ObesityGliosisWeight LossDiabetes Mellitus, Type 2

Interventions

Gastric Bypass

Condition Hierarchy (Ancestors)

OverweightOvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and SymptomsPathologic ProcessesBody Weight ChangesDiabetes MellitusGlucose Metabolism DisordersMetabolic DiseasesEndocrine System Diseases

Intervention Hierarchy (Ancestors)

Bariatric SurgeryBariatricsObesity ManagementTherapeuticsGastroenterostomyAnastomosis, SurgicalSurgical Procedures, OperativeDigestive System Surgical Procedures

Results Point of Contact

Title
Ellen Schur, MD, MS
Organization
University of Washington

Study Officials

  • Ellen Schur, MD, MS

    University of Washington

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NON RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor, School of Medicine: General Internal Medicine

Study Record Dates

First Submitted

June 25, 2018

First Posted

July 6, 2018

Study Start

June 1, 2019

Primary Completion

June 30, 2024

Study Completion

June 30, 2025

Last Updated

September 4, 2025

Results First Posted

July 28, 2025

Record last verified: 2025-08

Locations