The Pimentel Laboratory focuses on the association between acute gastroenteritis and disruption of gut flora, impairment of gastrointestinal (GI) tract motility and small intestinal bacterial overgrowth (SIBO) in the pathophysiology of irritable bowel syndrome (IBS). The research includes basic science and physiology, as well as clinical and translational research. Since autoimmunity and vinculin modulation may be the root events in IBS that lead from food poisoning to SIBO, the Pimentel Lab aims to manipulate this in two ways to attain a “cure” for IBS through 1) reducing the circulating autoantibodies to CdtB, which attack vinculin, and 2) activating or enhancing vinculin activity. The Pimentel group is also pursuing therapies that target Methanobrevibacter smithii, which they hypothesize causes C-IBS. Since an antibiotic approach produces only a short-lived response, they are developing drugs that have known inhibitory effects on methane synthesis by these organisms in a “drugs for bugs” approach.
Cultured intestinal flora in an agar plate.
Gel electrophoresis of PCR amplification on total versus methane-producing gut bacteria.
The Pimentel Laboratory has many ongoing basic science, translational and clinical research projects with the overarching aim of increasing our understanding of the gut microbiome and its role in human health and disease. One of the most ambitious of these is a large-scale effort to understand the small bowel microbiome for the first time. Since the small intestine is the absorbing surface, elements that bacteria produce here are more likely to be absorbed and impact health. The Pimentel Lab is convinced that these studies will lead to the development of a growing series of discoveries and potential microbiome based treatments.
In the laboratory, the Pimentel team has a number of research projects related to:
- Inflammation after acute gastroenteritis
- Mechanism of development of disease
- Role of host-immune responses in IBS
- Shifts in gut flora microbial species associated with disease
- Correlations between gut methane, gut transit, gut flora, constipation/diarrhea, metabolic symptoms and obesity
These studies are designed to provide answers that will lead to deeper investigations.
Validation of Breath Test Prototype
The purpose of this study is to evaluate an investigational method of breath testing. Researchers aim to determine whether analysis of an additional gas (hydrogen sulfide) will improve their ability to diagnose and treat patients with small intestinal bacterial overgrowth. The study will compare breath gas testing that includes measurement of hydrogen sulfide to the standard testing, which measures only methane and hydrogen gas.
Colonic Inertia Pilot Study
The purpose of this pilot study is to identify the causes of a condition called colonic inertia, which involves severe constipation. Researchers aim to determine whether colonic inertia can be caused by changes in the types of microbes that are present in the colon, or possibly by a toxin produced by particular microbes.
Small Intestinal Sampling Study
The purpose of the study is to understand how microorganisms in the gut affect individuals and how they may contribute to gut-related human diseases.
Irritable Bowel Syndrome Study
The purpose of this study is to understand the causes of irritable bowel syndrome by looking at both genetic and immunologic mechanisms.