Jin Satoh

Alteration of aquaporin mRNA expression after small bowel resection in the rat residual ileum and colon

Background: Diarrhea occurring after small bowel resection gradually improves due to intestinal adaptation. It is known that several water channels, termed aquaporins (AQP), are expressed in the gastrointestinal tract and facilitate water transport. However, the changes of AQP after bowel resection remain unclear. In the present paper, the alterations in AQP mRNA expression were investigated after a massive small bowel resection in the rat residual ileum and colon.

Clinical importance of n-3 fatty acid-rich diet and nutritional education for the maintenance of remission in Crohn's disease

Abstract: Elemental diet (ED) therapy has been established as primary therapy for Crohns disease, and home enteral nutrition (HEN) has been reported to control relapse at a dose of more than 30 kcal/kg of ideal body weight. However, a decrease in ED compliance with long-term use is becoming problem. We developed an n-3 fatty acid-rich diet and carried out nutritional education specifically for Crohns disease patients using HEN to facilitate compliance and to improve their nutritional status. After the introduction of this n-3 rich diet, disease activity was not altered, and nutritional status, especially serum n-3 fatty acid levels, improved. The remission periods in patients with poor compliance seemed to be prolonged by the nutritional education. Thus, a n-3 rich diet in combination with nutritional education specific for Crohns disease patients is very important for the in maintenance of high compliance and for maintaining nutritional balance.

Nutritional benefits of enteral alanyl‐glutamine supplementation on rat small intestinal damage induced by cyclophosphamide

Background: Glutamine is the principal fuel used by the small intestine. Although the parental administration of glutamine promotes intestinal mucosal growth, it is controversial whether enteral glutamine is effective against small intestinal damage caused by chemotherapy. To further evaluate the benefits of enteral supplementation, peptide and amino acid transporter functions must be considered.

Medium-chain triglycerides modulate ileitis induced by trinitrobenzene sulfonic acid

Background : It is important to develop an appropriate animal model for further investigation into inflammatory bowel disease (IBD). We therefore investigated a trinitrobenzene sulfonic acid (TNBS) ileitis model. Dietary fat in Crohn’s disease is still a controversial risk factor for IBD. We therefore also studied the effects of medium‐chain triglycerides (MCT) and long‐chain triglycerides (LCT) on TNBS ileitis.

Is fish oil (n-3 fatty acids) effective for the maintenance of remission in Crohn's disease?

Despite the strong evidence linking diet with the pathogenesis of Crohn’ s disease, the mechanism and nature of this link remains unclear. There has been growing interest in the importance of nutritional factors in the pathogenesis of Crohn’s disease. In fact, dietary therapy, either with total parenteral nutrition or an elemental diet, has been successful as primary treatment for Crohn’s disease. O’ Morain et al.7 showed that treatment with an elemental diet was as effective as treatment with corticosteroids in patients with Crohn’s disease in a controlled study. The fundamental role of dietary therapy is to remove intraluminal factors that can induce or maintain intestinal inflammation. We have demonstrated that intestinal CD4 T cells expressing selected T-cell receptor (TCR) V â chains are preferentially activated in the inflamed terminal ileum in patients with Crohn’s disease and that T-cell lines established from these cells show increased cytolytic activity and produce large amounts of T helper (Th)1 type cytokines, such as interleukin (IL)-2 and interferon (IFN)-γ.8 Our results strongly suggest that activated CD4 T cells infiltrated in the intestinal mucosa could respond to luminal antigens derived from food or intestinal microbes. Nutritional therapy in Crohn’s disease may reduce the interaction between intestinal stimulants and immune competent cells. This therapy also alleviates nutrient deficiencies and improves nutritional status, which may, indirectly, affect symptoms and the patients comfort. The importance of n-3 fatty acids in the prevention of intestinal inflammation in Crohn’s disease has been proposed by several investigators. The low incidence of Crohn’s disease in Japan for the past few decades suggests that a fish-oil-rich diet has protected Japanese populations against occurrence of the disease. The incidence of Crohn’s disease in Japan has been increasing in recent years, and this is correlated with increased dietary fat intake and decreased oily fish intake. On the basis of the results of these epidemiological studies, Crohn’s disease is a chronic inflammatory bowel disease, characterized by the infiltration of activated T cells and monocytes/macrophages in the intestinal wall; but its pathogenesis remains obscure. In 1979, the National Cooperative Crohn’s Disease Study (NCCDS) showed that the response of active Crohn’s disease to prednisone or sulfasalazine was significantly better than the response to placebo. However, none of the drugs, such as corticosteroids, azathioprine, or sulfasalazine, were superior to placebo for the maintenance of remission in that study of 20 years ago.1 Although several new therapies, such as anti-tumor necrosis factor (TNF) α chimera-antibody and immunosuppressants, have been employed for the treatment of active Crohn’s disease, there is no established treatment for the management of quiescent Crohn’s disease. Recent studies have demonstrated some effectiveness of 5-aminosalicylate (5ASA) with a new delivery system2 and azathioprine3 for maintaining remission. We have shown that low-dose 6-mercaptopurine (6MP) was effective in treating Japanese patients with Crohn’s disease who were corticosteroid-dependent or had associated fistula.4 It is important to prevent the relapse of patients with quiescent Crohn’s disease, and home enteral nutrition (HEN) is widely used in Japan for the maintenance of remission.5 However, compliance with HEN is poor and most patients cannot bear the long-term HEN treatment. Thus, a novel therapy for preventing relapse is awaited. In this issue of the Journal, Tsujikawa et al.6 report the efficacy of an n-3 fatty acids-rich diet, in combination with nutritional education, in patients with Crohn’s disease to maintain the quiescent periods after the induction of remission and to resolve the poor compliance with nutritional therapy. This may be a great boon to patients with Crohn’s disease who find it difficult to comply with the large amounts HEN.

Medium-chain triglyceride-rich enteral nutrition is more effective than low-fat enteral nutrition in rat colitis, but is equal in enteritis

Background. Although enteral nutrition (EN) therapy for Crohns disease has been confirmed to be as effective as steroid therapy, the precise mechanism responsible for the effects of EN remains unclear, although some of the therapeutic effects of EN are believed to be due to a low dietary fat content. In order to elucidate the influence of fat in EN, it is important to investigate not only the quantity of fat, but also the source of the fat. Methods. We compared two enteral nutritional formulae: Elental (Ajinomoto) (elemental diet; ED), which contains only 1.5% fat, provided as long-chain triglycerides (LCT), versus Twinline (Snow Brand Milk Products) (TL), which contains a high percentage of fat (20.4%), provided mainly as medium-chain triglycerides (MCT). These formulae were tested on rat enteritis and rat colitis induced by trinitrobenzene sulfonic acid (TNBS). Results. Both ED and TL reduced the manifestations of enteritis. TL had a stronger anti-inflammatory effect than ED for colitis. TL also had nutritional advantages as compared with ED, as shown by the total serum protein in the TL group being significantly higher than that in the ED group. Conclusion. The results indicate that intraluminal MCT is suitable as a fat energy source during intestinal inflammation in rats. We suggest that Twinline may be more useful to improve nutritional status and to re-duce the mucosal inflammation in rat colitis, but that Twinline is equal in effect to Elental for rat enteritis.

Different-sized triglycerides chains do not influence colitis induced by trinitrobenzene sulfonic acid in rats

Abstract An elemental diet (ED) was established as a primary therapy for patients with Crohn’s disease, and one of its therapeutic mechanism might be due to its low fat content. However, it is thought to be important to investigate not only the quantity of dietary fat, but also the quality of the dietary fat. We therefore studied the effects of medium chain triglycerides (MCT) versus long chain triglycerides (LCT) on colitis induced by trinitrobenzene sulfonic acid (TNBS) in rats in order to investigate whether enteral nutrition containing different-sized triglycerides chain influence intestinal inflammation. An elemental diet containing MCT or LCT was administered for 7 days through an intragastric catheter after an intracolonic injection of TNBS. The mucosal damage series in both groups did not differ significantly. The myeloperoxidase activities, leukotriene B4 levels and interleukin-8 levels also did not change between the MCT and LCT groups. These results indicated that 7 days of administration of different-sized triglycerides did not influence the rat colitis induced by TNBS.