Ulcerative Colitis: Neut C

Karrout Y, Neut C, Wils D, Siepmann F, Deremaux L, Flament MP, Dubreuil L, Desreumaux P, Siepmann J. · College of Pharmacy, JE 2491, Universite Lille Nord de France, 3 rue du Professeur Laguesse, 59006 Lille, France. · Eur J Pharm Sci. · Pubmed #19491034 No free full text.

Abstract: The aim of this study was to prepare and characterize novel types of polymer coated pellets allowing for the site-specific delivery of drugs to the colon. 5-Aminosalicylic acid (5-ASA)-loaded beads were prepared by extrusion-spheronization and coated with different Nutriose:ethylcellulose blends. In vitro drug release from these systems was measured under various conditions, including the exposure to fresh fecal samples from inflammatory bowel disease patients under anaerobic conditions. Nutriose is a starch derivative, which is preferentially degraded by enzymes secreted by the microflora in the colon of Crohn's disease and ulcerative colitis patients. Interestingly, the release of 5-ASA (which is commonly used for the local treatment of inflammatory bowel diseases) could effectively be suppressed upon exposure to release media simulating the conditions in the upper GIT, irrespective of the degree of agitation and presence or absence of enzymes. But as soon as the pellets came into contact with fecal samples of inflammatory bowel disease patients, the release rate significantly increased and the drug was released in a time-controlled manner. Thus, this novel type of colon targeting system is adapted to the pathophysiology of the patient. Furthermore, culture media containing specific colonic bacteria are presented providing an interesting potential as substitutes for fresh fecal samples.

Karrout Y, Neut C, Wils D, Siepmann F, Deremaux L, Desreumaux P, Siepmann J. · College of Pharmacy, JE 2491, University of Lille, 3 rue du Professeur Laguesse, 59006 Lille, France. · Int J Pharm. · Pubmed #19135511 No free full text.

Abstract: The major aim of this work was to optimize the properties of novel polymeric films based on blends of ethylcellulose and Nutriose (a water-soluble, branched dextrin). Such blends were recently shown to be highly promising for the site-specific delivery of drugs to the colon in patients suffering from inflammatory bowel diseases, in particular Crohn's disease and ulcerative colitis. Importantly, and in contrast to various other colon targeting approaches, the system is adapted to the pathophysiological conditions in the disease state. However, it is yet unknown how desired membrane properties, especially water uptake and dry mass loss kinetics as well as mechanical stability can be adjusted to the specific needs of particular drug treatments. Different highly efficient and easy to apply tools were identified altering the membrane's properties, in particular their mechanical resistance required to withstand the shear forces resulting from the motility of the upper GIT and the hydrostatic pressure built up within the devices upon contact with aqueous media. This includes the variation of the Nutriose:ethylcellulose blend ratio and initial plasticizer content. Importantly, Nutriose also exhibits significant pre-biotic activity, normalizing the microflora in the patients' colon, which is of major clinical benefit in the case of inflammatory bowel diseases.

Darfeuille-Michaud A, Boudeau J, Bulois P, Neut C, Glasser AL, Barnich N, Bringer MA, Swidsinski A, Beaugerie L, Colombel JF. · Pathogénie Bactérienne Intestinale, Laboratoire de Bactériologie, Université d'Auvergne, Clermont-Ferrand, France. · Gastroenterology. · Pubmed #15300573 No free full text.

Abstract: BACKGROUND & AIMS: Adherent-invasive Escherichia coli (AIEC) pathovar has been identified in the intestinal mucosa of patients with Crohn's disease (CD). AIEC reference strain LF82 is able to adhere to intestinal epithelial cells, to invade epithelial cells via a mechanism involving actin polymerization and microtubules, and to survive and replicate within macrophages. This study was performed to assess the prevalence of AIEC associated with intestinal mucosa of patients with CD, ulcerative colitis (UC), and of controls. METHODS: A search for E. coli strains was performed with ileal specimens of 63 patients with CD and 16 controls without inflammatory bowel disease (IBD), and with colonic specimens of 27 patients with CD, 8 patients with UC, and 102 controls. The abilities of E. coli strains to invade epithelial cells and to survive and replicate within macrophages were assessed using the gentamicin protection assay. Bacterial uptake by epithelial cells was analyzed using cytoskeletal inhibitors. Bacterial adhesion was quantified with Caco-2 and Intestine-407 cells. The presence of known E. coli virulence genes was assessed by polymerase chain reaction and DNA hybridization. RESULTS: In ileal specimens, AIEC strains were found in 21.7% of CD chronic lesions vs. in 6.2% of controls. In neoterminal ileal specimens, AIEC strains were found in 36.4% of CD early lesions (P = 0.034 vs. controls) and 22.2% of healthy mucosa of CD patients. In colonic specimens, AIEC strains were found in 3.7% of CD patients, 0% of UC patients, and 1.9% of controls. CONCLUSIONS: AIEC strains are associated specifically with ileal mucosa in CD.