EVOC - EVs in Obesity and Cardiometabolic Disease (EVOC)

Extracellular Vesicle Signaling in Obesity and Cardiometabolic Disease (EVOC)

The goal of this observational study is to research the impact of molecular signals from the heart, liver and fat tissue on cardiovascular disease risk, and the presentation of Type II Diabetes and diseases that affect the heart, blood vessels and metabolism (Cardiometabolic Disease). Specifically, the focus is on the content and function of Extracellular Vesicles (EVs), small sacs released from a cell's surface that contain important molecular cargo. The main questions it aims to answer are:

1. What molecular cargo do adipose-tissue EVs carry?
2. How do these cargo impact cardiac and hepatic function?
3. Are changes in EV content related to cardiac function and adiposity with weight loss?

Tissue samples from fat tissue and blood samples will be collected from patients receiving bariatric weight loss surgery.

Study Overview

• Status: Recruiting
• Conditions: Cardiovascular Diseases

Detailed Description

The primary clinical objective of this research is to study the impact of molecular signals from the adipose tissue to the heart, liver and brain on cardiovascular disease risk in obesity, Type II Diabetes and other metabolic diseases that affect the heart, blood vessels and metabolism (Cardiometabolic Disease). Specifically, the focus is on the content and function of Extracellular Vesicles (EVs), small sacs released from a cell's surface that contain important molecular cargo. The hypothesis is that EVs derived from metabolically active fat tissue located around the abdominal organs (visceral adipose tissue) have a different cargo than those derived from non-metabolically active fat tissue located directly under the skin (subcutaneous adipose tissue), and that these cargoes impact the function of other organs. Further, we hypothesize that visceral adipose EVs are also present in the plasma in circulation, and that the content changes as patients become metabolically healthy following bariatric surgery.

After obtaining patient consent, samples from visceral fat tissue, subcutaneous fat tissue and blood will be collected during the gastric bypass weight loss surgery. These samples will be brought to lab where they will be processed for EVs. Subject's medical history and records will be followed as well. An optional, secondary blood draw may be collected 3 month post-surgery or within 24 months.

Following collection, the samples will be brough to the laboratory of the PI for processing. Samples will undergo characterization for proteins, extracellular or exosomal RNAs, tissue RNAs (e.g., leukocyte/buffy coat), and/or metabolites. A trascriptomic and proteomic analysis will be performed to determine differences in protein and RNA expression. The EVs will be extracted from subcutaneous and visceral fat tissue and used to treat heart muscle cells and liver-on-chip cells that have been produced in a laboratory setting.

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Saumya Das, MD, PhD; Phone Number: 617-724-4500; Email: SDAS@mgh.harvard.edu

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02114-2696
      • Recruiting
      • Massachusetts General Hospital
      • Principal Investigator: Saumya Das, MD/PhD
      • Contact: Clinical Research Coordinator; Phone Number: 617-643-9621; Email: cazzam@mgh.harvard.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of 100 eligible subjects with obesity (BMI>/=30 kg/m2) who are planned to undergo bariatric surgery recruited from the clinic of Dr. Denise Gee in the Weight Center at Massachusetts General Hospital.

Description

Inclusion Criteria:

• Age greater than or equal to 18 years of age
• Obese (BMI>/=30 kg/m2; for obesity/bariatric surgery group)
• For 20 patients, additional criteria will be presence of pre-diabetes or diabetes (HgbA1c > 5.7 or Fasting blood glucose > 100).

Exclusion Criteria:

• Pregnancy (as adjudicated by patient history)
• Prior clinical history of myocardial infarction or valvular heart disease

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Bariatric Surgery; Patients undergoing bariatric surgery

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
What are the contents inside of fat (adipose) tissue derived Extracellular Vesicles (EVs)?	The study staff aim to obtain EVs from fat samples obtained at the time of bariatric weight loss surgery. The activity of genes within the cargo of the collected EVs are assessed using RNA sequencing and protein contents analysis. A statistical analysis performed utilizing computer technology will provide us with differentially expressed cargo that may be a step in the molecular communication pathway to the heart and liver tissues.	2 years
How does the contents of Extracellular Vesicles (EVs) impact cardiac and liver function?	The study will look at the functional role of EVs from visceral and subcutaneous fat tissue on 3D organ on chip (liver on chip) and the heart's muscle cells (cardiomyocytes) using microscopes, gene expression and an assessment of the cardiomyocyte's electrical properties. It is predicted that changes in the recipient cell's gene expression will correlate with the contents discovered in Outcome 1.	2 years
Are changes in Extracellular Vesicle (EV) content related to cardiac function and adiposity with weight loss?	EVs collected from fat tissue are present in blood and provide a minimally invasive method to determine the fat cell's activity for turning food to into energy. We aim to assess how the content of EVs collected from plasma within the blood, and the content related to fat tissue EVs from Objective 1 change with weight loss.	2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
How does the presence of diabetes or pre-diabetes alter the RNA content of Extracellular Vesicles?	The fat samples will be categorized based on the presence of diabetes, pre-diabetes and no diabetes of the subject at the time of weight loss surgery.	2 years

Collaborators and Investigators

• Sponsor: Massachusetts General Hospital
• Collaborators: American Heart Association
• Investigators: Principal Investigator: Saumya Das, MD, PhD, Massachusetts General Hospital

Publications and helpful links

General Publications

• Chatterjee E, Betti MJ, Sheng Q, Lin P, Emont MP, Li G, Amancherla K, Garcia-Contreras M, Gokulnath P, Limpitikul WB, Whittaker OR, Luong K, Azzam C, Gee D, Hutter M, Flanders K, Sahu P, Flynn CR, Brown J, Yu D, Rosen ED, Van-Keuren Jensen K, Gamazon ER, Shah R, Das S. The extracellular vesicle transcriptome provides tissue-specific functional genomic annotation relevant to disease susceptibility in obesity. Cell Genom. 2025 Sep 10;5(9):100925. doi: 10.1016/j.xgen.2025.100925. Epub 2025 Jul 15.

Study record dates

Study Major Dates

• Study Start (Actual): February 2, 2019
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): July 1, 2028

Study Registration Dates

• First Submitted: May 7, 2024
• First Submitted That Met QC Criteria: May 7, 2024
• First Posted (Actual): May 10, 2024

Study Record Updates

• Last Update Posted (Actual): June 17, 2026
• Last Update Submitted That Met QC Criteria: June 15, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Type II Diabetes; Cardiovascular Risk; Extracellular Vesicles; Cardiometabolic Disease
• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Nutritional and Metabolic Diseases; Diabetes Mellitus, Type 2; Cardiovascular Diseases
• Other Study ID Numbers: 2022P002665

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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