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Radiotherapy plays an important role in cancer treatment, although it may cause collateral effects and sever complications due to cellular damage of peritumoral tissues. Recently different nutritional resources have been indicated to achieve intestinal protection during cancer irradiation. The aim of this study was to set the role of glutamine in acute actinic enteritis prevention. Sixty-five Wistar male rats (200 g) were maintained in individual metabolic cages, where body weight and food ingestion were carefully monitored daily. The animals were chosen at random in three groups and fed isocaloric and isoproteid diets: 1) CRt (23)-polymeric-casein diet (CD); 2) GRt (22)-polymeric-casein diet supplemented with 2% glutamine (GD), and 3) ERt (20)--elemental diet supplemented with 2% glutamine (ED). After an adaptation period (seven days), all rats received 1500 cGy of abdominal radiation in five equal daily doses of 300 cGy. After three days post radiation the rats were submitted to jejunal perfusion test with polyethylene-glicol 4000. Finally, small bowel and colon were resected for histological evaluation. It was observed that ERt group had greater average daily food intake than CRt and GRt groups during all periods (p < 0.05). All rats had equal weight gain during adaptation period; during irradiation all the animals had weight loss, but ERt group had smaller weight loss than CRt. All rats recovered weight after irradiation, and ERt group presented better results than the others (p < 0.05). Sodium transepithelial transport average values (mEq/min/cm) were negative and not statistically different in all groups. Small bowel histological evaluation in ERt and GRt rats were better than CRt rats, by preserving mucosal cellularity and increasing mitosis number and villi length (p < 0.05). Simultaneously, ERt group had greater number of rats with normal villuscrypt relation than CRt of CRt groups (p < 0.05). Large bowel histological data showed that the average crypt's length in ERt and GRt rats were greater than in CRt ones (p < 0.05). By the present work, an elemental diet enriched with 2% glutamine favored greater food ingestion and lessened weight loss during and after radiotherapy. Glutamine-supplemented polymeric or elemental diets given to rats before, during and after abdominal radiotherapy showed protective effects against radiation injury, by supporting mucosal structure and recovery.

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Increased concentrations of the soluble form of the interleukin 2 receptor have been observed in the sera of Crohn's disease and ulcerative colitis patients. In this study we have observed the spontaneous release of soluble interleukin 2 receptor by unstimulated, isolated normal and inflammatory bowel disease colonic lamina propria mononuclear cells. Lamina propria mononuclear cells from Crohn's disease patients (median = 204 U/ml (interquartile range 126-396, n 17) secreted significantly (p less than 0.01) more soluble interleukin 2 receptor than normal controls (median = 124.5 U/ml (108-131), n 12). No statistically significant differences were seen between ulcerative colitis (median = 135 U/ml (92-196), n 20) and normal controls. Moreover, significantly (p less than 0.01) increased amounts of soluble interleukin 2 receptor were secreted by colonic diverticulitis lamina propria mononuclear cells (median = 259 U/ml (149-282), n 15) which were used as disease specificity controls. Time course experiments showed that the majority of soluble interleukin 2 receptor was released by isolated lamina propria mononuclear cells in the first six days of culture. Upon stimulation with pokeweed mitogen, Crohn's disease (median = 2258 U/ml (1435-3584), n 14), normal control (median = 2622 U/ml (2030-3180), n 14) and diverticulitis lamina propria mononuclear cells (median = 2745 U/ml (1733-3192), n 10) reached similar maximal soluble interleukin 2 receptor secretion levels, while ulcerative colitis lamina propria mononuclear cells secreted significantly (p less than 0.005) less soluble interleukin 2 receptor (median = 912 U/ml (494-1259), n 17). These results suggest that enhanced shedding/secretion of soluble interleukin 2 receptor by intestinal lymphocytes may account in part for increased serum soluble interleukin 2 receptor concentrations during chronic intestinal inflammatory reactions.

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The fermentation of pectin by colonic bacteria produces short-chain fatty acids (SCFA) which are then absorbed by the host. The purpose of this study was to determine whether pectin, added to a chemically defined diet, would increase hepatic lipogenesis and whether this effect is mediated by intestinal bacteria. Eighteen Sprague-Dawley rats underwent placement of a feeding gastrostomy and a swivel apparatus. Postoperatively, rats were randomly assigned to one of three groups: 1) No Pectin received a fat-free chemically defined diet, 2) Pectin received the same diet with the addition of 1% (w/v) pectin, and 3) Neomycin received the same diet with 1% w/v pectin and neomycin (80 mg/kg of body weight daily). On the 5th postoperative d, all diets included 12.5% (v/v) deuterium as D2O. After the infusion of the labeled diets for 24 hr, the content and deuterium enrichment of liver palmitate, stearate and oleate were measured and the production rates calculated. The liver content and production rates of these fatty acids were higher in Pectin animals than in either the No Pectin or Neomycin animals. Since the effect of pectin on hepatic lipogenesis was reduced by the concomitant administration of the intestinal antibiotic neomycin, it appears that this effect depends on the bacterial fermentation of pectin. It is postulated that the SCFA produced during pectin fermentation promote lipogenesis via a direct stimulatory effect, in addition to being carbon donors.

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