Takashi Yasuoka

Effects of the Soluble Fibre Pectin on Intestinal Cell Proliferation, Fecal Short Chain Fatty Acid Production and Microbial Population

Aim: Although pectin, a dietary fibre, has been suggested to possess some trophic effects on the intestine, the mechanisms involved remain unclear. This study aimed to evaluate the effects of pectin on rat intestinal cell proliferation and the intraluminal environment. Methods: Control and pectin-fed rats were given a fibre-free elemental diet (ED) and an ED containing 2.5% pectin, respectively. On the 15th day, the length, weight and number of Ki-67-positive cells from each intestinal segment, and the short chain fatty acids (SCFAs) and microbial population in the caecum were measured. Plasma glucagon-like peptide-2 (GLP-2) concentration and GLP-2 receptor (GLP-2R) mRNA levels in the epithelium were also determined. Results: Pectin supplementation resulted in significant increases in the length, weight, and number of Ki-67-positive cells in the ileum, caecum and colon. Although pectin supplementation did not affect the caecal microbial flora that produced SCFAs, the caecal SCFA content was significantly increased. Pectin supplementation also induced an increase in the plasma GLP-2 concentration, but did not affect the GLP-2R mRNA levels in the small intestine. Conclusions: The increases in the caecal SCFAs and plasma GLP-2 levels induced by pectin supplementation may cause mucosal proliferation in the lower intestinal tract.

Changes in the prevalence of Helicobacter pylori infection and gastrointestinal diseases in the past 17 years.

Background and Aims:  The aim of the study was to examine whether the change in the prevalence of Helicobacter pylori infection had influenced upper gastrointestinal diseases in a recent 17‐year period.

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.

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.

The effects of lectins on indomethacin‐induced small intestinal ulceration

Summary.  Growth factors, such as epidermal growth factor and keratinocyte growth factor, have considerable therapeutic potential for repairing mucosal injury in the intestine when given systemically. Recently, several lectins have been shown to have trophic effects on the intestine when given orally. We examined the effects of phytohaemagglutinin (PHA) and concanavalin A (Con‐A) on indomethacin‐induced intestinal injury in rat. Five‐week‐old rats were randomized to four groups (n = 5), and intestinal injury was induced by indomethacin injection in three of these groups. Elemental diet (ED) feeding was then commenced. The groups were thus ED feeding/indomethacin untreated (control group), ED feeding/indomethacin treated (ED group), 0.1% PHA‐supplemented ED feeding/indomethacin treated (PHA group) and 0.1% Con‐A‐supplemented ED feeding/indomethacin treated (Con‐A group). After 7 days of feeding, macroscopic inflammatory scores, mucosal permeability, myeloperoxidase (MPO) activities and cell proliferation were determined. Macroscopic inflammatory scores, mucosal permeability and MPO activities were significantly lower in both lectin groups than that in control group. Twenty‐four hour excretion rate of phenolsulphonphthalein was significantly lower in both lectin groups than that in ED group. Cell proliferation of the small intestine was significantly increased by both lectins. Lectin supplementation can induce ulcer healing following indomethacin‐induced damage.