Gut Organoid and Microbiome Interactions in Hypertension

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.

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