Gut Organoid and Microbiome Interactions in Hypertension

Completed

Conditions: Gut Inflammation
Hypertension

Registration Number: NCT04497727

Lead Sponsor: University of Florida

Brief Summary: The study compared basic properties of gut epithelia of hypertensive and normotensive reference subjects. The study determined if there are fundamental differences in the gut epithelium in hypertension compared to normotension. Specifically, this study examined gene expression profiles of gut organoids derived from biopsy samples of hypertensive and normotensive individuals undergoing clinically indicated colonoscopy.

Detailed Description: This investigated whether there is a difference in gut epithelia between individuals with and without high blood pressure by comparing colonic biopsy samples from. The study was conducted among adults undergoing routine elective colonoscopy at the University of Florida. Participants were classified into high blood pressure (HBP) and normotensive (REF) groups based on blood pressure criteria defined by the 2017 ACC/AHA guidelines.

The study had two primary aims. Aim 1 was to evaluate whether gene expression patterns in the gut epithelium differ between hypertensive and normotensive individuals using RNA sequencing. Aim 2 was to assess whether gut organoids-three-dimensional epithelial cultures derived from colonic biopsies-exhibit different growth rates and proportions, using immunohistochemistry and fluorescence-activated cell sorting (FACS).

Biopsy specimens were collected during clinically indicated colonoscopies. Tissue samples were processed immediately after collection: one portion was snap-frozen for RNA isolation and sequencing; the other was used to establish gut organoid cultures. Data were coded and stored in a secure, encrypted database with all identifiers removed to protect confidentiality, in compliance with HIPAA regulations.

Although the study protocol initially planned to recruit 60 participants, a total of 35 subjects were successfully enrolled-16 with high blood pressure (HBP) and 19 normotensive (REF) participants. All provided adequate biopsy material for gene expression analysis.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 35

Inclusion Criteria

Inclusion/exclusion criteria for hypertension participants
Ages: 18-80 years old with a weight greater than or equal to 110 lbs
Diagnosis of hypertension or without hypertension for the reference cohort. 2017 ACC/AHA (American College of Cardiology/American Heart Association) definition for hypertension (systolic blood pressure ≥130 mmHg and/or diastolic BP ≥80 mmHg) will be used.
Scheduled elective colonoscopy

Exclusion Criteria

Hypertensive or reference individuals with history of autoimmune disease or other chronic inflammatory conditions.
Pregnant or have been pregnant in the last six months.
Antibiotic treatment within two months of study enrollment
Currently taking a medication (e.g. antibiotic, anti-inflammatory agents, glucocorticoids, other immune modulating medications, antacids or proton pump inhibitor drugs like Prilosec) known to modify gut microbiota.
Unwilling to discontinue using probiotics for at least two weeks before scheduled biopsy.
History of intestinal surgery, inflammatory bowel disease, celiac disease, lactose intolerance, chronic pancreatitis or other malabsorption disorder.
History of blood transfusion within 4 weeks.
Subjects who, in the opinion of the investigator, will be uncooperative or unable to comply with study procedures

Study & Design

Study Type: OBSERVATIONAL

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Differential Gene Expression in Gut Epithelium	At time of colonoscopy (single visit)	Number of differentially expressed genes identified through RNA sequencing of colonic epithelial tissue obtained during colonoscopy. Expression profiles were compared between individuals with High Blood pressure (HBP) (hypertensive group) and normotensive reference (REF) participants. Genes were considered differentially expressed if they met criteria of false discovery rate (FDR)-adjusted p-value \< 0.05 and absolute fold change ≥ 1.5.
Growth Rates of Gut Organoids	Within days to weeks post-biopsy (in vitro culture period)	To compare growth rates and proportions of gut organoids derived from High Blood pressure (HBP) vs. normotensive (REF) participants.

Secondary Outcome Measures