• Parasites, Hosts and Diseases
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• 제49권2호
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• pp.177-180
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• 2011

Entamoeba histolytica is an enteric tissue-invading protozoan parasite that can cause amebic colitis and liver abscess in humans. E. histolytica has the capability to kill colon epithelial cells in vitro; however, information regarding the role of calpain in colon cell death induced by ameba is limited. In this study, we investigated whether calpains are involved in the E. histolytica-induced cell death of HT-29 colonic epithelial cells. When HT-29 cells were co-incubated with E. histolytica, the propidium iodide stained dead cells markedly increased compared to that in HT-29 cells incubated with medium alone. This pro-death effect induced by ameba was effectively blocked by pretreatment of HT-29 cells with the calpain inhibitor, calpeptin. Moreover, knockdown of m- and ${\mu}$-calpain by siRNA significantly reduced E. histolytica-induced HT-29 cell death. These results suggest that m- and ${\mu}$-calpain may be involved in colon epithelial cell death induced by E. histolytica.

• Parasites, Hosts and Diseases
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• 제51권1호
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• pp.61-68
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• 2013

Entamoeba histolytica, which causes amoebic colitis and occasionally liver abscess in humans, is able to induce host cell death. However, signaling mechanisms of colon cell death induced by E. histolytica are not fully elucidated. In this study, we investigated the signaling role of NOX in cell death of HT29 colonic epithelial cells induced by E. histolytica. Incubation of HT29 cells with amoebic trophozoites resulted in DNA fragmentation that is a hallmark of apoptotic cell death. In addition, E. histolytica generate intracellular reactive oxygen species (ROS) in a contact-dependent manner. Inhibition of intracellular ROS level with treatment with DPI, an inhibitor of NADPH oxidases (NOXs), decreased Entamoebainduced ROS generation and cell death in HT29 cells. However, pan-caspase inhibitor did not affect E. histolytica-induced HT29 cell death. In HT29 cells, catalytic subunit NOX1 and regulatory subunit Rac1 for NOX1 activation were highly expressed. We next investigated whether NADPH oxidase 1 (NOX1)-derived ROS is closely associated with HT29 cell death induced by E. histolytica. Suppression of Rac1 by siRNA significantly inhibited Entamoeba-induced cell death. Moreover, knockdown of NOX1 by siRNA, effectively inhibited E. histolytica-triggered DNA fragmentation in HT29 cells. These results suggest that NOX1-derived ROS is required for apoptotic cell death in HT29 colon epithelial cells induced by E. histolytica.

• Advances in pediatric surgery
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• 제4권1호
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• pp.74-78
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• 1998

Early recognition and surgical treatment of Hirschsprung's disease prevents serious mortality and morbidity from enterocolitis and obstruction. Usually this disease is characterized by a single aganglionic segment of the colon extending distally to the anal margin. In surgical treatment, the surgeon performs a frozen section biopsy to confirm whether there are ganglion cells. If there are intervening ganglionic sites in aganglionic bowel, there may be confusion in diagnosis and treatment. The authors experienced one case of total colonic aganglionosis with skip area. A transverse loop colostomy was performed on a 7 day-old male baby with colon perforation due to Hirschsprung's disease. But intestinal obstruction persisted and required two more operations to find the true nature of the disease. There were aganglionic segments from the anal margin to the terminal ileum 3.7cm proximal to the ileocecal valve. The entire transverse colon and appendix were normally ganglionated.

• 사상체질의학회지
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• 제27권2호
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• pp.254-269
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• 2015

Objectives This study aimed to observe the effect of Taeumjowi-tang on the cisplatin-induced gastrointestinal dysfunctions in rats. Methods Four groups, each of 8 rats per group, were used in this study. Saline and distilled water treated control rats were intact vehicle control group. Delayed gastrointestinal motility was induced by intraperitoneal treatment of cisplatin 2mg/kg, once a week for 5 weeks(Cisplatin control group). Taeumjowi-tang aqueous extracts(TJ) were orally administered in a volume of 5ml/kg, once a day for 14 days from 4th cisplatin treatment(TJ group). Ondansetron 1mg/kg was subcutaneously treated, in a volume of 1ml/kg, as same as TJ(ondansetron group). We measured the body weights, intestinal charcoal transit ratio, fecal parameters, fundus MDA(malondialdehyde), GSH(glutathione) contents and SOD(superoxide dismutase), CAT(catalase) activities, TPH(tryptophanhydroxylase) and MAO(monoamine oxidase) activities, pyloric gastrin and serotonin contents with their immunoreactive cells, colonic serotonin-immunoreactive cells, the histopathology of pylorus, fundus mucosa and colon. Results 1) The body weight gains, the small intestinal charcoal transfer rates, the fecal parameters(numbers, weights and water contents) were increased in TJ, ondansetron group. 2) The inhibit of fundus antioxidant defense systems by cisplatin were decreased in TJ, ondansetron group. 3) The pyloric TPH activities were increased and the pyloric MAO activities were decreased in TJ group. 4) The pyloric gastric contents and the gastrin-immunoreactive cells were increased and the pyloric serotonin contents and the pyloric and colonic serotonin-immunoreactive cells were decreased in TJ group. 5) The pylorus atrophic changes and the gastric surface erosive damage regions by cisplatin were favorably inhibited by treatment of TJ group. Conclusions The results obtained in this study suggest that TJ favorably retarded the cisplatin related GI(gastrointestinal) dysfunctions and constipation through modulations of GI enterochromaffin cells, serotonin and gastrin-producing cells and antioxidative systems.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3473-3477
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• 2015

Plants and their by-products offer a diverse mixture of chemical constituents like natural antioxidants. Date-pits are rich in phenolic compounds that have antioxidant potential. The main objective of this study was to investigate the protective effect of a date-pit extract (DPE) against AOM-induced colonic carcinogenicity and oxidative stress. Thirty-two weanling male Sprauge-Dawley rats were randomly divided into four groups (eight rats in each group). All rats were fed basic diet and water ad libitum, and randomly distributed per treatment groups as follows: negative controls injected with normal saline once a week for two weeks, a cancer group injected intra-peritoneally with azoxymethane (15mg/kg body weight) for two consecutive weeks, and DPE treated groups receiving the extract via the oral route (1.5ml/day) for the entire experiment in the presence or absence of AOM injection. Results showed that DPE contained phytonutrients that were capable of inhibiting chemically-induced oxidative stress in the rat colonic cells. In those animals that consumed DPE, a protective effect was observed against AOM-induced oxidative stress in rat colonic cells as evident by a significant decrease in MDA and oxidized DCF formation in AOM injected and DPE fed groups. It is concluded that DPE has potential antioxidant and anticarcinogenic properties.

• 대한수의학회지
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• 제52권2호
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• pp.115-124
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• 2012

Colorectal cancer (CRC) is one of the leading causes of cancer death in western countries or in the developed countries. Zinc intake has been associated with decreased risk of CRC. We investigated the effect of zinc on the formation of colonic aberrant crypt foci (ACF) induced by azoxymethane followed by dextran sodium sulfate in mice. Five-week old ICR mice were fed with the different zinc levels (0.01, 0.1, 1 ppm) for 12 weeks. The numbers of ACF were measured in the colonic mucosa. The ACF number of HZn group was significantly low compared with LZn group or MZn group. Cytosolic superoxide dismutase activity was the highest in HZn group, while thiobarbituric acid reactive substance level for lipid peroxidation was the highest in LZn group. There was no difference in number of PCNA-positive proliferative cells among the groups. TUNEL-positive apoptotic cells were increased in HZn group compared with LZn group. The HZn group exhibited a decrease of ${\beta}$-catenin immunostaining areas compared with the LZn or MZn group. These findings indicate that dietary zinc might exert a protecting effect against colon carcinogenesis by inhibiting the development of ACF in the mice.

• IMMUNE NETWORK
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• 제6권1호
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• pp.13-19
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• 2006

Background: Granulocyte colony stimulating factor (G-CSF) is known as a cytokine central to the hematopoiesis of blood cells and to modulate their cellular functions. Besides granulocytes and their precursors, monocytes/macrophages and endothelial cells are direct target cells of G-CSF action. G-CSF influences immune cells in an anti inflammatory way. Methods: To evaluate whether G-CSF has a potential for preventing or ameliorating diseases characterized by mucosal inflammation, we used a mouse model with trinitrobenzene sulfonic acid (TNBS)-induced inflammatory colitis. To the mice model G-CSF was administrated daily by intraperitoneal injection. Macroscopic evaluation and immunohistochemical analysis of colonic tissues were performed. Results: Re combinant human G-CSF significantly inhibited LPS-induced TNF-${\alpha}$ mRNA expression in THP-1 cells. As for in vivo relevance, G-CSF dramatically reduced the weight loss of mice, colonic damage, and mucosal ulceration that characterize TNBS colitis. Moreover, G-CSF suppressed the expression of tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$, and intercellular adhesion molecule-1 in TNBS colitis. Conclusion: Current results demonstrate that G-CSF may be an effective agent for the treatment of diseases characterized by mucosal inflammation.

• Journal of Nutrition and Health
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• 제55권1호
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• pp.47-58
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• 2022

Purpose: Obesity and a high-fat diet (HFD) are risk factors for colorectal cancer. We have previously shown that luteolin (LUT) supplementation in HFD-fed mice markedly inhibits tumor development in chemically induced colon carcinogenesis. In this study, we evaluated the anticancer effect of LUT in the inhibition of cell proliferation in HFD-fed obese mice and HT-29 human colorectal adenocarcinoma cells grown in an adipocyte-derived medium. Methods: C57BL/6 mice were fed a normal diet (ND, 11.69% fat out of total calories consumed, n = 10), HFD (40% fat out of total calories consumed, n = 10), HFD with 0.0025% LUT (n = 10), and HFD with 0.005% LUT (n = 10) and were subjected to azoxymethane-dextran sulfate sodium chemical colon carcinogenesis. All mice were fed the experimental diet for 11 weeks. 3T3-L1 preadipocytes and HT-29 cells were treated with various doses of LUT in an adipocyte-conditioned medium (Ad-CM). Results: The weekly body weight changes in the LUT groups were similar to those in the HFD group; however, the survival rates of the LUT group were higher than those of the HFD group. Impaired crypt integrity of the colonic mucosa in the HFD group was observed to be restored in the LUT group. The colonic expression of proliferating cell nuclear antigen and insulin-like growth factor 1 (IGF-1) receptors were suppressed by the LUT supplementation in the HFD-fed mice. The LUT treatment (10, 20, and 40 µM) inhibited the proliferation and migration of HT-29 cells cultured in Ad-CM in a dose-dependent manner, as well as the differentiation of 3T3-L1 preadipocytes. Conclusion: These results suggest that the anticancer effect of LUT is probably due to the inhibition of IGF-1 signaling and adipogenesis-related cell proliferation in colon cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2235-2245
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• 2016

Ulcerative colitis (UC) results from colonic epithelial barrier defects and impaired mucosal immune responses. In this study, we aimed to investigate the modifying effects of a Spirogyra neglecta extract (SNE), a polysaccharide extract (PE) and a chloroform fraction (CF) on dextran sodium sulfate (DSS)-induced colitis in mice and to determine the mechanisms. To induce colitis, ICR mice received 3% DSS in their drinking water for 7 days. Seven days preceding the DSS treatment, oral administration of SNE, PE and CF at doses of 50, 25 and 0.25 mg/kg body weight (low dose), 200, 100 and 1 mg/kg body weight (high dose) and vehicle was started and continued for 14 days. Histologic findings showed that DSS-induced damage of colonic epithelial structure and inflammation was attenuated in mice pre-treated with SNE, PE and CF. Furthermore, SNE and PE significantly protected colonic epithelial cells from DSS-induced cell cycle arrest, while SNE, PE and CF significantly diminished apoptosis. Proteome analysis demonstrated that SNE and PE might ameliorate DSS-induced colitis by inducing antioxidant enzymes, restoring impaired mitochondria function, and regulating inflammatory cytokines, proliferation and apoptosis. These results suggest that SNE and PE could prevent DSS-induced colitis in ICR mice by protection against and/or aiding recovery from damage to the colonic epithelium, reducing ROS and maintaining normal mitochondrial function and apoptosis.

• 대한의생명과학회지
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• 제18권4호
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• pp.362-368
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• 2012

Enterotoxigenic Bacteroides fragilis (ETBF) is an intestinal commensal bacterium implicated as a risk factor for colon cancer. The key virulence factor is a secreted toxin called B. fragilis toxin (BFT). In this study we used an in vitro bioassay to examine the prevalence of ETBF in colonic washings from patients with colorectal polyps and normal control patients. We found that 9.3% of polyp patients and 10.9% of non-polyp patients harbored ETBF, respectively. A total of nine ETBF clinical isolates were isolated and confirmed to be positive for the BFT gene by PCR analysis and the ability to induce IL-8 secretion in the colonic epithelial cell line HT29/c1. Two of the ETBF clinical strains were characterized further in vitro and in vivo. We found that the two ETBF clinical isolates induced E-cadherin cleavage in HT29/c1 cells and promoted colonic inflammation in C57BL/6 mice. Our results indicate that the prevalence of ETBF in polyp patients were similar in non-polyp patients suggesting that ETBF carriage does not positively correlate to polyp incidence.