Time-Related Evidence of Intestinal Oxidative Stress in Obstructive Jaundice-Induced Rats.

INTRODUCTION: Obstructive jaundice is known to affect intestinal permeability and facilitate bacterial translocation through related mechanisms. This study was conducted to evaluate the alterations concerning blood biochemistry and levels of several markers of oxidative stress (OS) in blood and intestinal mucosa caused by obstructive jaundice and how these fluctuate over time, in order to further explore the possibility of intervening in the OS path in future experiments. METHODS: A total of 54 albino Wistar rats were randomly divided into three groups (control, sham operated, and bile duct ligation) and sacrificed at specific time intervals (12 h and 2, 7, and 14 days). The intestinal barrier function was evaluated by measuring endotoxin levels in portal, aortic, and peripheral blood. Also, basic biochemical parameters were simultaneously measured in peripheral blood. Tissue samples collected from the terminal ileum were homogenized for determining the OS markers, lipid peroxidation, and protein-free radical-induced oxidation. RESULTS: We designed this experiment to examine the alterations in enteric mucosa primarily in relation to OS in a period of 14 days. During this time period, we investigated in specific time intervals not only OS fluctuations but also other liver function parameters, as well as CRP and endotoxin levels. The alterations were monitored in relation to time after bile duct ligation. CONCLUSION: Bile duct ligation in rats causes OS versus post-ligation time progression of the common bile duct. OS was increased by ∼50% compared to control/sham and peaked at 7 days and at least up to 14 days post-ligation. This phenomenon was accompanied with a deranging of liver function after ligation, as anticipated, but not in all measured parameters; biochemical and endotoxin levels followed the same pattern.

Beneficial effect of synbiotics on experimental colon cancer in rats.

BACKGROUND/AIMS: The aim of this study was to investigate the influence of a synbiotic preparation (a mixture of six probiotics and a prebiotic) on aberrant crypt foci (ACF) formation, dysplasia, inflammation, and colitis-like lesions in experimental colon cancer in rats. MATERIALS AND METHODS: Sixty male rats were categorized into three groups of 20 animals each. Group A was administered 1,2-dimethylydrazine, 15 mg/kg body weight (BW), once a week for 2 weeks. Group B was administered 1,2-dimethylydrazine at the same dose plus synbiotic, started after the second dose of carcinogen and lasted for 5 weeks. Group C was administered synbiotic plus carcinogen from the beginning of the experiment and lasted for 7 weeks. Animals were killed at the end of week 7. RESULTS: At the end of the experiment, the animals that received carcinogen plus the synbiotic had 100%, whereas the animals that received only carcinogen has 70% survival. Animals of groups B and C had significantly lower percentage of inflammation, colitis-like lesions, and ACF dysplasia than animals of group A, whereas those of group C had the least pathological lesions. CONCLUSION: Synbiotics seem to protect against the appearance of preneoplastic colon lesions in rats. The results of this experimental study suggest that treatment with a synbiotic preparation exerts significant antimutagenic properties against the development of preneoplastic lesions in rats.

Effect of Infliximab and Adalimumab on Experimental Colitis Following Orally Supplemented Iron.

BACKGROUND: Orally administered iron can induce colonic inflammation in healthy animals and aggravate experimental colitis. AIM: To investigate the influence of the biologic agents infliximab and adalimumab on the severity of TNBS colitis following orally supplemented iron. MATERIALS-METHODS: 204 Wistar rats were allocated into 14 groups. Colitis was induced by TNBS. Iron was administered via a mouth catheter at a dose of 0.027, 0.3, and 3%/kg diet per day, respectively. Infliximab was subcutaneously administered on the 2nd and 6th day in a dose of 5 mg/kgBW, while adalimumab was administered on the 2nd day in a dose of 2 mg/kgBW. On the 8th day, all animals were euthanatized. Activity of colitis and extent of tissue damage were assessed histologically. Tissue Tumor Necrosis Factor-α (t-TNF-α) and malondialdehyde (t-MDA) were estimated. RESULTS: In normal rats both agents significantly worsen the degree of inflammation induced by moderate or high iron supplementation despite the disappearance of t-TNF-α, and reduction of t-MDA. In the groups of TNBS colitis and moderate or high iron administration, both agents again significantly worsen the degree of inflammation despite the significant reduction in the t-TNF-α and t-MDA. CONCLUSION: Adalimumab and infliximab do not ameliorate the inflammation in TNBS-induced colitis aggravated by orally administered iron. These findings might be clinically relevant in patients with active IBD under concurrent treatment with biologic agents and per oral iron.

The role of enteral nutrition in patients with inflammatory bowel disease: current aspects.

Enteral nutrition (EN) is considered to be of great importance in patients with inflammatory bowel disease (IBD) and nutritional problems. This comprehensive review is aiming to provide the reader with an update on the role of EN in IBD patients. EN can reduce Crohn's disease (CD) activity and maintain remission in both adults and children. Nutritional support using liquid formulas should be considered for CD patients and in serious cases of ulcerative colitis (UC), especially for those who may require prolonged cycles of corticosteroids. Given that the ultimate goal in the treatment of CD is mucosal healing, this advantage of EN over corticosteroid treatment is valuable in therapeutic decision-making. EN is indicated in active CD, in cases of steroid intolerance, in patient's refusal of steroids, in combination with steroids in undernourished individuals, and in patients with an inflammatory stenosis of the small intestine. No differences between the efficiency of elemental diets and nonelemental formulas have been noticed. EN must be the first choice compared to TPN. EN has a restricted value in the treatment of patients with large bowel CD. In conclusion, it seems important not to underestimate the role of nutrition as supportive care in patients with IBD.

Cyclin D1 and Rb protein expression and their correlation with prognosis in patients with colon cancer.

BACKGROUND: Cyclin D1 plays a major role as a potential contributor to the multistep process of oncogenesis; nevertheless its prognostic significance in colon cancer has already been examined in a few studies and needs to be further delineated. The aim of this study was to assess the expression of cyclin D1 and pRb and to correlate them with tumor histological stage and grade, proliferative capacity (Ki-67 labeling index) and clinical parameters, in order to delineate their impact on prognosis. METHODS: One hundred and eleven patients, who underwent surgical resection of the colon for colon cancer constituted the group of our study. The immunohistochemical expression of cyclin D1, Rb and Ki-67 proteins was examined and correlated with clinico-pathological parameters and survival. RESULTS: The 5-years survival rate of patients presenting cyclin D1 positive tumors was 54%, while that of cyclin D1 negative ones was 67% (P = or > 0.05). The survival rate of patients with pRb positive tumors was similar to that of pRb negative ones. Significant association was observed between Ki-67 and cyclin D1 positivity (P = 0.045). Univariate analysis revealed worse survival in advanced stage patients presenting cyclin D1 positive tumors (P = 0.025). Additionally, the survival of patients aging less than 70 years old was correlated to cyclin D1 positivity (P = 0.009). Multivariate survival analysis revealed statistical significance for stage and hepatic metastasis. CONCLUSION: Even though cyclin D1 and pRb have not disclosed any clear association with shorter survival, cyclin D1 positivity may be a useful predictor of subgroup patients with colon cancer being in advanced stage and early age.