Recruiting

Extracellular Vesicles

Sponsor:

University of Colorado, Boulder

Code:

NCT06776081

Conditions

Obesity

Weight Loss

Eligibility Criteria

Sex: All

Age: 40+

Healthy Volunteers: Accepted

Interventions

Weight loss without pharmacotherapy

Study Details

Brief summary:

Changes in adipose tissue biology are now recognized as a key factor underlying the increased risk of metabolic and cardiovascular disease with obesity. Clinical interest in adipocyte-derived extracellular vesicles (Ad-EVs) has intensified due to their potential as circulating biomarkers of adipose tissue health and systemic messengers, regulators and mediators of cardiometabolic health and disease with obesity.

The investigators hypothesize that elevated Ad-EVs in adults with obesity will be negatively associated with endothelium-dependent vasodilation. Furthermore, the investigators hypothesize that in adults with obesity, intentional weight loss-induced reduction in circulating Ad-EVs is associated with greater endothelium-dependent vasodilation.

Conditions

Obesity

Weight Loss

Study ID

NCT06776081

Start date

Jul 1, 2024

Status verified date

Apr, 2026

Completion date

Jun 30, 2027

Anticipated

Primary completion date

Jun 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 40+

Healthy Volunteers: Accepted

Inclusion criteria:

  • Age ≥40 years
  • BMI <25 kg/m2 and BMI >25 kg/m2 for Phase 1 and BMI >25 kg/m2 for Phase 2. Rationale for defining obesity as BMI >25 kg/m2

Exclusion criteria:

  • Current smoker
  • Chronic overt medical condition (e.g., evidence of coronary artery disease on resting ECG, any history of myocardial infarction or stroke, or cancer, diabetes based on fasting blood glucose concentration)
  • Alcohol abuse or dependence defined as more than 14 standard drinks/week and no more than 4 standard drinks/day for men and 7 standard drinks/week and 3 standard drinks/day for women (a standard drink is defined as 12 ounces of beer, 5 ounces of wines, 1 ½ ounces of 80-proof distilled spirits) reported during the medical history/physical exam
  • Stage III hypertension (systolic blood pressure >160 mmHg and/or diastolic blood pressure >100 mmHg)
  • Regular vigorous aerobic/endurance exercise (>3 bouts/week, >30 minutes/bout at a workload >6 METS)
  • Women who are pregnant or breastfeeding
  • History of anaphylaxis to betadine, lidocaine, iodine
  • Raynaud's disease
  • History of clotting disorders
  • Anyone taking blood thinners and clotting medications
  • Anyone taking statin medication
  • Planned pregnancy in coming 4-6 months

Study Design

Enrollment

84 participants

Anticipated

Allocation

Non randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

no intervention: No Intervention: Phase 1

Phase 1 is a cross-sectional study to compare whether circulating Ad-EVs are associated with obesity-related endothelial dysfunction in normal weight adults and adults with obesity.

experimental: Experimental: Phase 2

Phase 2 employs an intervention study design, to determine in adults with obesity, the effects of intentional weight loss (12-weeks) on circulating Ad-EVs and their effect on endothelium-dependent vasodilation.

Interventions

Weight loss without pharmacotherapy

Adults with obesity participating in the 12-week hypocaloric diet-induced weight loss intervention will be individually counseled by the Clinical and Translational Research Center (CTRC) bionutritionist to consume a hypocaloric diet consistent with current dietary recommendations for weight loss until a 6-10% weight loss is achieved.

Primary outcome measure

  • Phase 1: Circulating adipocyte-derived extracellular vesicles (Ad-EVs) [ Time Frame: Circulating Ad-EVs will measured during Phase 1 visit 2 which is ~2 weeks from their respective start date. ]
  • Phase 2: Circulating adipocyte-derived extracellular vesicles (Ad-EVs) [ Time Frame: Circulating Ad-EVs will be measured during Phase 2 visit 15 which is ~17 weeks from their respective start date. ]
  • Phase 1: Forearm Blood Flow (FBF) Response to Acetylcholine (ACh) [ Time Frame: FBF response to ACh will be measured during Phase 1 and the participant's visit 2 which is ~ 2 weeks from their respective start date. ]
  • Phase 2: Forearm Blood Flow (FBF) Response to Acetylcholine (ACh) [ Time Frame: FBF response to ACh will be measured during Phase 2 and the participant's visit 15 which is ~17 weeks from their respective start date. ]
  • Phase 1: Forearm Blood Flow (FBF) Response to Sodium Nitroprusside (NTP) [ Time Frame: FBF response to NTP will be measured during Phase 1 and the participant's visit 2 which is ~ 2 weeks from their respective start date. ]
  • Phase 2: Forearm Blood Flow (FBF) Response to Sodium Nitroprusside (NTP) [ Time Frame: FBF response to NTP will be measured during Phase 2 and the participant's visit 15 which is ~17 weeks from their respective start date. ]

Central Contacts and Locations

Central contacts

Jared Greiner, MS

303-735-3605greinerj@colorado.edu

Locations

University of Colorado Boulder Clinical and Translational Research Center (CTRC)

Recruiting

Boulder, Colorado, United States, 80309

Contacts

Jared Greiner, MS

303-735-3056greinerj@colorado.edu

More Information

Sponsor

University of Colorado, Boulder

Last update posted

Apr 28, 2026

Last verified

Apr, 2026

Keywords

  • Obesity
  • Weight Loss

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Colorado, Boulder on 2026-04-28.