Diagnostic and therapeutic targets in chronic digestive and brain pathologies
Development of diagnostic imaging methods of UNGE.
My research project in 1 video ...
This line of research is transversal to all three previous axes.
It aims to develop innovative imaging tools, especially endoscopic, to characterize the lesions of UNGE during digestive diseases and the brain. Its goal is to identify new diagnostic biomarkers predictive of disease progression or response to treatment.
In addition, this axis also aims to develop and validate new therapeutic and preventive approaches targeting UNGE disorders in pathologies of interest. These approaches are based on the one hand on the use of neurostimulation methods (stimulation of sacred roots in inflammatory diseases). On the other hand, we are also developing research focused on the use of nutritional compounds (short chain fatty acids, lipid mediators, probiotics) or pharmacological compounds.
This last line is developed in close collaboration with all the clinical services (Gastroenterology-Nutrition-Digestive Surgery) and research (CIC-IMAD, UMR Phan) of IMAD.
What is known :
graft-versus-host disease (GVHD) is a set of lesions caused by the action of the donor immune system against recipient tissues in patients who have received allogeneic bone marrow transplantation for the treatment of hematologic disease
GVH can affect many organs: skin, kidneys, digestive tract, liver ...
GVH is severe, frequent and difficult to diagnose
Confocal endomicroscopy (CME) is an optical technique for real-time in vivo microscopy imaging by applying a probe to a tissue
Previous group results :
EMC performed during rectosigmoidoscopy in a small number of asymptomatic transplant patients shows early lesions
The current project :
to create an EMC score to assess intestinal mucosal lesions in early GVHD
characterize the involvement of the intestinal epithelial barrier and enteric nervous system in GVH
Figure : patterns of confocal endomicroscopy observed in patients with gastrointestinal graft-versus-host disease (GVHD) after fluorescein injection. A) normal sigmoid B) abnormal microvessel network with dilatation of a microvessel surrounding a colonic crypt (mild GVHD) C) slight increase in fluorescein intensity in the lamina propria (mild GVHD) D) cryptic distortion (moderate GVHD) ) E and F) Major architectural modifications with proliferation and dilation of microvessels in the lamina propria, major extravasation of fluorescein and destruction of colonic crypt architecture (severe GVHD)
What is known :
irritable bowel syndrome (IBS) is a common and multifactorial condition that causes abdominal pain and transit disorders
some patients with IBS have an increase in intestinal permeability
the microbiota probably plays a role in the pathophysiology of IBS
there are multiple methods to measure intestinal permeability: ex vivo measurement in Ussing chamber, in vivo measurement by measurement of urinary excretion of sugars, confocal endomicroscopy
The current project
to measure changes in intestinal permeability and enteric glia phenotype of probiotic treatment in patients with diarrhea-type irritable bowel syndrome