Intestinal epithelial cells in inflammatory bowel diseases

The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important element is represented by the intestinal barrier, a complex system formed mostly by intestinal epithelial cells (IECs). IECs have an active role in producing mucus and regulating its composition; they provide a physical barrier capable of controlling antigen traff ic through the intestinal mucosa. At the same time, they are able to play the role of non-professional antigen presenting cells, by processing and presenting antigens directly to the cells of the intestinal immune system. On the other hand, immune cells regulate epithelial growth and differentiation, producing a continuous bi-directional cross-talk within the barrier. Several alterations of the barrier function have been identif ied in IBD, starting from mucus features up to its components, from epithelial junctions up to the Toll-like receptors, and altered immune responses. It remains to be understood whether these defects are primary causes of epithelial damage or secondary effects. We review the possible role of the epithelial barrier and particularly describe the role of IECs in the pathogenesis of IBD.

A new oral formulation for the release of sodium butyrate in the ileo-cecal region and colon

AIM： To develop a new formulation with hydroxy propyl methyl cellulose and Shellac coating for extended and selective delivery of butyrate in the ileo-caecal region and colon. METHODS： One-gram sodium butyrate coated tablets containing ^13C-butyrate were orally administered to 12 healbhy subjects and 12 Crohn＇s disease patients and the rate of ^13C-butyrate absorption was evaluated by t3CO2 breath test analysis for eight hours. Tauroursodeoxycholic acid （500 rag） was co-administered as a biomarker of oro-ileal transit time to determine also the site of release and absorption of butyrate by the time of its serum maximum concentration. RESULTS： The coated formulation delayed the ^13C-butyrate release by 2-3 h with respect to the uncoated tablets. Sodium butyrate was delivered in the intestine of all subjects and a more variable transit time was found in Crohn＇s disease patients than in healthy subjects. The variability of the peak ^13CO2 in the kinetic release of butyrate was explained by the inter-subject variability in transit time. However, the coating chosen ensured an efficient release of the active compound even in patients with a short transit time. CONCLUSION： Simultaneous evaluation of breath ^13CO2 and tauroursodeoxycholic acid concentrationtime curves has shown that the new oral formulation consistently releases sodium butyrate in the ileo-cecal region and colon both in healthy subjects and Crohn＇s disease patients with variable intestinal transit time. This formulation may be of therapeutic value in inflammatory bowel disease patients due to the appropriate release of the active compound.

Inflammatory bowel disease: Moving toward a stem cell-based therapy

The incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel diseases (IBD), are rising in western countries. The modern hygienic lifestyle is probably at the root of a disease where, in genetically susceptible hosts, the intestinal commensal flora triggers dysregulated immune and inflammatory responses. Current therapies ranging from anti-inflammatory drugs to immunosuppressive regimens, remain inadequate. Advances in our understanding of the cell populations involved in the pathogenetic processes and recent findings on the regenerative, trophic and immunoregulatory potential of stem cells open new paths in IBD therapy. Hematopoietic and mesenchymal stem cells are catalyzing the attention of IBD investigators. This review highlights the pivotal fi ndings for stem cell-based approaches to IBD therapy and collects the encouraging results coming in from clinical trials.

A new iron free treatment with oral fish cartilage polysaccharide for iron deficiency chronic anemia in inflammatory bowel diseases:A pilot study

AIM： To investigate the effect of a new oral preparation, highly concentrated in fish cartilage, in a group of inflammatory bowel diseases （IBD） patients with chronic iron deficient anemia. METHODS： In an open label pilot study, we supplemented a group of 25 patients （11 with Crohn＇s disease and 14 with ulcerative colitis） in stable clinical conditions and chronic anemia with a food supplement which does not contain iron but contains a standardized fraction of fish cartilage glycosaminoglycans and a mixture of antioxidants （Captafer Medestea, Turin, Italy）. Patients received 500 mg, twice a day during meals, for at least 4 mo. Patients were suggested to maintain their alimentary habit. At time 0 and after 2 and 4 too, emocrome, sideremia and ferritin were examined. Paired data were analyzed with Student＇s t test. RESULTS： Three patients relapsed during the study （2 in the 3^rd too, 1 in the 4^th too）, two patients were lost to follow up and two patients dropped out （1 for orticaria, 1 for gastric burning）. Of the remaining 18 patients, levels of serum iron started to rapidly increase within the 2^nd mo of treatment, P 〈 0.05）, whereas serum ferritin and hemoglobin needed a longer period to significantly improve their serum levels （too 4） P 〈 0.05. The product was safe, easy to administer and well tolerated by patients. CONCLUSION： These data suggest a potential new treatment for IBD patients with iron deficiency chronic anemia and warrant further larger controlled studies.

Combination of corticosteroids and 5-aminosalicylates or corticosteroids alone for patients with moderate-severe active ulcerative colitis:A global survey of physicians'practice

AIM To examine treatment decisions of gastroenterologists regarding the choice of prescribing 5-aminosalycilates(5ASA) with corticosteroids(CS) versus corticosteroids alone for patients with active ulcerative colitis(UC). METHODS A cross-sectional questionnaire exploring physicians' attitude toward 5ASA + CS combination therapy vs CS alone was developed and validated. The questionnaire was distributed to gastroenterology experts in twelve countries in five continents. Respondents' agreement with stated treatment choices were assessed by standardized Likert scale. Background professional characteristics of respondents were analyzed for correlation with responses. RESULTS Six hundred and sixty-four questionnaires were distributed and 349 received(52.6% response rate). Of 340 eligible respondents, 221(65%) would continue 5ASA in a patient hospitalized for intravenous CS treatment due to a moderate-severe UC flare, while 108(32%) would stop the 5ASA(P < 0.001), and 11(3%) are undecided. Similarly, 62% would continue 5ASA in an out-patient starting oral CS. However, only 140/340(41%) would proactively start 5ASA in a hospitalized patient not receiving 5ASA before admission. Most(94%) physicians consider the safety profile of 5ASA as very good. Only 52% consider them inexpensive, 35% perceive them to be expensive and 12% are undecided. On multi-variable analysis, less years of practice and perception of a plausible additive mechanistic effect of 5ASA + CS were positively associated with the decision to continue 5ASA with CS. CONCLUSION Despite the absence of data supporting its benefit, most gastroenterologists endorse combination of 5ASA + CS for patients with active moderate-to-severe UC. Randomized controlled trials are needed to assess if 5ASA confer any benefit for these patients.