An European team of researchers made new progress in the treatment of inflammatory bowel disease. Inflammatory bowel disease, which includes ulcerative colitis and Crohn’s disease are chronic diseases of the digestive tract of unknown etiology. Symptoms of these two diseases are similar but there, however, are some differences. Crohn’s disease affects mainly the terminal ileum, has transmural lesions that are asymmetric and discontinuous, while ulcerative colitis affects especially the rectum and the lesions are continuous and are only present in the mucosa. IBD can cause both digestive symptoms such as pain, diarrhea, rectal bleeding, and extra-digestive symptoms and signs such as weight loss, anemia, joint pain, uveitis, etc.. It must be mentioned that IBD can cause a number of serious complications requiring emergency treatment, such as massive bleeding, peritonitis, perforation, ileus, etc..
It seems that IBD occurs due to a disorder of the immune system, and this is caused by environmental and genetic factors. Several genes were studied: major histocompatibility complex genes (HLA DR and DQ), genes encoding TNF alpha, NOD2 etc; it seems that those who have mutations in the NOD2 gene have a higher risk of developing Crohn’s disease. Regarding environmental factors, there appears to be an inappropriate immune response to specific antigens such as Listeria, Mycobacterium, etc., which causes an inflammation of the lining mucosa. However, we do not know the exact cause of IBD.
IBD treatment consists of several drugs that relieve symptoms: derivatives of 5-ASA, corticosteroids, immunosuppressive agents, biological response modifiers (anti-TNF alpha monoclonal antibody) or surgical treatment. Drugs are not effective for all patients and in addition they also have many side effects. Regarding surgery, it must be said that sometimes surgery can cure ulcerative colitis, but there are also situations when the disease recurs. Now a team of researchers in Europe have conducted research to better understand the causes IBD and focused on specific enzymes called matrix metalloproteases (MMPs). MMPs degrade other proteins such as those found in the spaces between cells, freeing the way for inflammatory cells to target tissue. These enzymes are controlled by tissue inhibitors of metalloproteases, TIMPs, and it seems that tissue damage and inflammation occur when there is an imbalance between these two.
Researchers have identified the enzymes that may be targets for TIMPs after comparing the expression of MMPs in healthy and chronically inflamed digestive tract. They also have found that the proteases associated with inflammation sometimes originate in bacteria from the digestive tract. This new perspective on the causes of IBD can be the basis for new therapeutic targets in the treatment of IBD.