- Peripheral pain mechanisms underlying irritable bowel syndrome and inflammatory bowel diseas
- Synthetic stool transplants for treating C. difficile colitis and potential “ecosystem therapeutics” for other disorders such as IBD, IBS and others (Petrof PI)
- Colon cleansing kits for colonoscopy
Key signaling molecules and targets of interest:
- mast cell and non mast cell proteases
- endogenous opioids in chronic inflammation
- FODMAP diets (low CHO) diets and their effect on the microbiome
Human models of study (current or potential):
- irritable bowel syndrome – indirect studies of microbiome using breath testing and combined Tc99 scintography; baraostat measurements of rectal sensory thresholds
- DNA methylation studies of colonic biopsies from colon cancer screening patients (Will King PI)
- fecal probiotic for treatment of C. difficile (Elaine Petrof PI)
- electrophysiology recordings from the human colon and the effects of stress hormones (joint program GIDRU members and General Surgery)
- GIDRU is developing a “human research laboratory” for comprehensive and capacity studies of humans
Animal models of study (existing or desired):
- post infectious IBS model – self limiting colitis induced by Citrobacter rodentium (a model of Human E. coli infection) combined with chronic stress – patch clamp, multi-unit afferent recordings, plus in vivo sensory threshold measurements with visceromotor reflexes
- acute and chronic models of IBD – TNBS, DSS (same techniques as 1.)
Biobanking of human samples (existing or desired):
- colonic biopsies from all disease from upper and lower GI tract; currently studying irritable bowel syndrome, IBD, and colon polyp/cancer patients
- stool samples for microbiome analysis; currently studying C. difficile colitis (Petof PI)
- access to blood and urine samples on all of above
A few relevant publications:
Ibeakanma C, Ochoa-Cortes F, Miranda-Morales M, McDonald T, Spreadbury I, Cenac N, Cattaruzza F, Hurlbut D, Vanner S, Bunnett N, Vergnolle N, & Vanner S (2011). Brain-gut interactions increase peripheral nociceptive signaling in mice with postinfectious irritable bowel syndrome. Gastroenterology 141, 2098-2108.
Yu D, Cheeseman F and Vanner S (2011). Combined oro-caecal scintigraphy and lactulose hydrogen breath testing demonstrate that breath testing detects oro-caecal transit, not small intestinal bacterial overgrowth in patients with IBS. Gut 60: 334-340.
Ibeakanma, C. and Vanner, S (2010). TNF alpha is a key mediator of the pronociceptive effects of mucosal supernatant from human ulcerative colitis on colonic DRG neurons. Gut 59:612-621,2010.