Research Interests

  • 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:

  1. mast cell and non mast cell proteases
  2. endogenous opioids in chronic inflammation
  3. FODMAP diets (low CHO) diets and their effect on the microbiome

 Human models of study (current or potential):

  1. irritable bowel syndrome – indirect studies of microbiome using breath testing and combined Tc99 scintography; baraostat measurements of rectal sensory thresholds
  2. DNA methylation studies of colonic biopsies from colon cancer screening patients (Will King PI)
  3. fecal probiotic for treatment of C. difficile (Elaine Petrof PI)
  4. electrophysiology recordings from the human colon and the effects of stress hormones (joint program GIDRU members and General Surgery)
  5. GIDRU is developing a “human research laboratory” for comprehensive and capacity studies of humans

 Animal models of study (existing or desired):

  1. 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
  2. acute and chronic models of IBD – TNBS, DSS (same techniques as 1.)

 Biobanking of human samples (existing or desired):

  1. colonic biopsies from all disease from upper and lower GI tract; currently studying irritable bowel syndrome, IBD, and colon polyp/cancer  patients
  2. stool samples for microbiome analysis; currently studying C. difficile colitis (Petof PI)
  3. 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.