Chemopreventive effect of mofezolac on beef tallow diet/azoxymethane-induced colon carcinogenesis in rats.

BACKGROUND/AIMS: We have previously shown that long-term consumption of 10% beef tallow diet promotes colon carcinogenesis in both saline- and azoxymethane (AOM)-treated rats. Here, we investigated the effects of mofezolac, a selective COX-1 inhibitor, on beef tallow-fed rats with saline- or AOM treatment. METHODOLOGY: Male SD rats were intraperitoneally injected with saline or AOM and fed 10% beef tallow diet with or without 1200 ppm mofezolac. At 12 weeks, aberrant crypt foci (ACF) were examined. At 44 weeks, tumors were counted, the proliferation and expression of COX-1 and 8-catenin on normal-appearing colonic mucosa was evaluated using the BrdU incorporation assay and Western blotting respectively. RESULTS: Mofezolac decreased the number of ACF at 12 weeks (p < 0.05) and reduced tumor multiplicity and incidence at 44 weeks in beef tallow-fed rats with AOM treatment (p < 0.05). At 44 weeks, reduction of the BrdU-positive cells (p < 0.05) and beneficial distribution changes of these cells within the colon crypts in both groups with mofezolac supplementation were observed. The expression of COX-1 and beta-catenin also reduced in mofezolac-added groups simultaneously (p < 0.05). CONCLUSIONS: This study suggested that mofezolac suppressed beef tallow-promoted colon carcinogenesis in rats, which probably was, appropriate for populations with high fat intake.

Functional disturbance of the stress-adaptation system in patients with scleroderma.

There have been several reports indicating the association between recent stress experiences and the onset or the exacerbation of rheumatic diseases, although few such reports exist in patients with scleroderma (SSc). The present study was performed to elucidate whether there were any functional disturbances in the neuro-endocrine-immune system as a homeostatic system upon stress in SSc patients. Various serum levels of stress-related hormones and cytokines were examined before and after a mental calculation stress test, and a basal questionnaire study of sense of coherence (SOC, which is related to the ability to cope with stress), recent stress experiences, and quality of life (QOL) was performed in 17 SSc patients and in 38 healthy volunteers. Physical QOL state was impaired in patients, but there were no differences in recent stress experiences and SOC scores between patients and controls. Basal serum cortisol levels were similar in patients and controls, but increased levels of proinflammatory cytokine and noradrenalin were seen in SSc patients. Characteristically, contrary to the control group, whose cortisol levels increased significantly following the mental calculation stress test, no significant increase was observed in the patients when post-test cortisol levels were compared to pre-test levels, suggesting a defect in the normal cortisol response upon stress in SSc patients. The present results suggest that there may be impaired function of the neuro-endocrine-immune system upon stress in SSc patients.

Imbalance in the stress-adaptation system in patients with inflammatory bowel disease.

AIM: Though inflammatory bowel disease (IBD) is known as a stress-related disorder, basic evidence for this claim is lacking. The current study was performed to investigate the function of the neuroendocrine-immune system as a main pathway in stress response and stress-coping ability and the associations among stress response, stress-coping ability, and disease activity in IBD patients. METHOD: A questionnaire was administered to obtain information concerning stress state and stress-coping ability (self-efficacy and sense of coherence [SOC]) in 78 IBD patients and 21 healthy volunteers. Blood samples were taken for determining the serum levels of various stress-related hormones and cytokines before and after a calculation stress test. RESULTS: Self-efficacy was significantly decreased in patients, though the degree of perceived stress and SOC did not differ between patients and controls. Basal levels of cortisol did not differ, but levels of adrenocorticotropic hormone, ß-endorphin and interleukin (IL)-6 were significantly higher in patients than in controls. In addition, the control group, but not the patient group, demonstrated significant differences in the basal cortisol levels between low and high SOC subgroups and between low and high perceived stress subgroups. Furthermore, IL-6 levels were significantly increased following the calculation stress test in patients only. CONCLUSION: Results indicate that IBD patients may have skewed neuroendocrine-immune systems and that emotional stress may aggravate the disease. Stress-management interventions might be useful, not only for patients' quality of life (QOL) but also for disease control.

Brief Questioning by Nursing Staffs before Endoscopic Examination May Not Always Pick Up Clinical Symptoms of Endoscopic Reflux Esophagitis.

The clinical features of patients reflux esophagitis without any symptoms have not been clearly demonstrated. This study evaluated the clinical features of patients with endoscopy-positive reflux esophagitis, who did not complain of symptoms, as detected by brief questioning by nursing staffs. Eight thousand and thirty-one patients not taking medication for gastrointestinal disease, were briefly asked about the presence of heartburn, dysphagia, odynophagia and acid regurgitation by nursing staffs before endoscopy for assessment of esophagitis utilizing the Los Angeles Classification. Endoscopically, 1199 (14.9%) patients were classified as positive for reflux esophagitis. The endoscope positive subjects who complain heartburn were 539/1199 (45.0%).The endoscope positive subjects who do not complain symptoms were 465 in 1199 positive reflux esophagitis (38.8%). We compared endoscopic positive subjects without any complain by brief question by nursing staffs to endoscopic positive subjects with heartburn. Male gender, no obesity, absence of hiatus hernia, and low-grade esophagitis were associated with endoscopy-positive patients who do not complain of symptoms. The results of this study indicated correct detection of clinical symptoms of reflux esophagitis might be not easy with brief questioning by nursing staffs before endoscopic examination.

Conjugated linoleic acid suppresses colon carcinogenesis in azoxymethane-pretreated rats with long-term feeding of diet containing beef tallow.

BACKGROUND: We have indicated previously that long-term feeding of beef tallow increases colorectal cancer in rats. In this study, we investigated the effects of conjugated linoleic acid (CLA) on colon carcinogenesis in rats under long-term feeding of beef tallow diets, pretreated with azoxymethane (AOM). METHODS: Six-week-old male Sprague-Dawley rats were fed with 10% beef tallow diet only, 10% beef tallow with 1% CLA in triglyceride form (CLA-TG), or 10% beef tallow with 1% CLA in free fatty acid form (CLA-FFA). Colon carcinogenesis was induced by two intraperitoneal injections of AOM. Aberrant crypt foci (ACFs) were examined at 12 weeks. Cancer, cell proliferation, apoptosis, Wnt signaling, and the arachidonic acid cascade were examined at 44 weeks. RESULTS: At 12 weeks, CLA-TG and CLA-FFA attenuated the increase in ACFs induced by 10% beef tallow and AOM pretreatment. At 44 weeks, both forms of CLA attenuated multiple colon cancers, and CLA-FFA reduced the incidence of colon cancer to 50% of that seen with CLA-TG. CLA-TG and CLA-FFA decreased the number of 5-bromo-2'-deoxyuridine-positive cells in AOM-pretreated rats fed with 10% beef tallow. CLA-FFA increased the number of apoptotic cells and the activity of caspase-3 in the colon mucosa, and CLA-TG enhanced the activity of caspase-3. Both forms of CLA suppressed Wnt signaling and the arachidonic acid cascade in rats treated with beef tallow and AOM. CONCLUSION: These results suggested that CLA-TG and CLA-FFA suppressed colon carcinogenesis in rats with long-term feeding of a 10% beef tallow diet, through several mechanisms. The results of the present study with rats might be applicable to humans.

Long-term ingestion of reduced glutathione suppressed an accelerating effect of beef tallow diet on colon carcinogenesis in rats.

PURPOSE: We have shown previously that long-term feeding of beef tallow increases colorectal cancer in rats. This study investigated the effects of enzymic antioxidant, reduced glutathione (GSH), on colon carcinogenesis in rats fed with beef tallow. METHODS: Colon carcinogenesis was induced by intraperitoneal injection of azoxymethane (AOM) to rats. Rats were fed with 10% beef tallow supplemented with or without 1% GSH in drinking water. Aberrant crypt foci (ACF) and expression of beta-catenin in colonic mucosa were examined at 12 weeks. Cancers, related substances of oxidative stress and arachidonic acid cascade in plasma and normal colonic mucosa were determined at 44 weeks. RESULTS: GSH attenuated the number of ACF increased by beef tallow, but GSH had no influence on expression of beta-catenin increased by AOM. Incidence of colon cancer was no different with or without GSH, but GSH attenuated the number of colon cancers in each rat. GSH suppressed plasma malondialdehyde concentration. GSH increased GSH concentration and activities of catalase, glutathione peroxidase and superoxide dismutase in colonic mucosa, and decreased cyclooxygenase-2, prostaglandin E2 and thromboxane B2 levels. CONCLUSIONS: This study indicated that GSH suppressed the number of ACF, but the attenuation of colon carcinogenesis was limited to the number of colon cancers, although anti-oxidative effects and suppressive effects of arachidonic acid cascade were demonstrated by several indexes. These results suggested that colon carcinogenesis enhanced by beef tallow was partly caused by oxidative stress and arachidonic acid cascade, which were reduced by GSH.

Indigestible material attenuated changes in apoptosis in the fasted rat jejunal mucosa.

We have previously demonstrated that fasting induced apoptosis and decreased cell proliferation in the rat intestinal mucosa. The aim was to investigate the effect of expanded polystyrene as indigestible material on apoptosis and cell proliferation in rat small intestinal mucosa during fasting. Male SD rats were divided into 3 groups. The first group was fed with chow and water ad libitum. The second group fasted for 72 hrs. The third group was fasted for 24 hrs and was fed expanded polystyrene. Intestinal apoptosis was evaluated by percent fragmented DNA assay, terminal deoxynucleotidyl transferase-mediated dUDP-biotin nick end-labeling (TUNEL) staining, and caspase-3 assay. Cell proliferation was analyzed by 5-bromo-2'-deoxyuridine (5-BrdU) uptake. Truncal vagotomy was performed to evaluate a role of the central nervous system. In the 72-hr fasted rat, mucosal height of the rat jejunum was decreased to 73% of that in rats fed ad libitum, and this decrease was partly restored to 90% in rats fed expanded polystyrene. The fragmented DNA was increased in fasted rats (28.0%) when compared with that in rats fed ad libitum (2.6%). The increase in fragmented DNA in fasted rats was recovered by feeding them expanded polystyrene (8.3%). TUNEL staining confirmed this result. The effect of polystyrene on apoptosis was decreased by truncal vagotomy. Expression of cleaved caspase-3 was increased in fasted rats, which was then decreased by feeding of expanded polystyrene. In contrast to apoptosis, feeding of expanded polystyrene had no reconstructive effect on 5-BrdU uptake in the intestinal epithelium, which was decreased by fasting to 60% of that in rats fed ad libitum. In conclusion, feeding of indigestible material partly restored the decrease in intestinal mucosal length in the fasted rats through the apoptotic pathway without any influence on BrdU uptake. Further exploration focused on the mechanism of this effect of indigestible material is required.

Suppression of intestinal mucosal apoptosis by ghrelin in fasting rats.

Ghrelin is mainly produced in the stomach and has several physiologic functions. The aim of this study was to investigate whether ghrelin regulates apoptosis in the small intestinal mucosa of fasting rats. Intestinal mucosal apoptosis was evaluated as the percentage of fragmented DNA, villus height, and terminal deoxynucleotidyl transferase-mediated dUDP-biotin nick end-labeling (TUNEL) staining and by Western blot analysis of caspase-3 in 48-hr fasting rats. Crypt cell proliferation was evaluated by counting the number of 5-bromo-2-deoxyuridine (BrdU) positive cells. Ghrelin was administered intraperitoneally at dosages of 2.5, 25, and 250 microg/kg per 48 hrs by continuous infusion via an Alzet micro-osmotic pump or injections at 12-hr intervals. Ghrelin was also infused in rats that underwent truncal vagotomy. The lowest dosage of ghrelin (2.5 microg/kg per 48 hrs) was administered into the third cerebroventricle. Ghrelin treatment attenuated the percentage of fragmented DNA in the small intestinal mucosa in 48-hr fasting rats in a dose-dependent manner. Continuous infusion of ghrelin and injections of ghrelin at 12-hr intervals suppressed intestinal apoptosis almost equally. This effect on apoptosis was not attenuated by truncal vagotomy. Cerebroventricular infusion of ghrelin also attenuated intestinal apoptosis. The antiapoptotic effect of ghrelin was confirmed by decreased TUNEL staining, recovery of the villus height, and decreased expression of caspase-3. BrdU uptake indicated that ghrelin enhanced cell proliferation in the intestinal crypt. Taken together, these data indicate that ghrelin enhanced intestinal growth with the suppression of small intestinal mucosal apoptosis in 48-hr fasting rats, suggesting that ghrelin controls intestinal function through the regulation of intestinal apoptosis.

Dysphagia in adult Japanese is not equivalent to the grade of endoscopic reflux esophagitis.

OBJECTIVE: This study was aimed to evaluate the correlation between dysphagia, detected by nursing staff in a brief interview and endoscopic findings in reflux esophagitis. PATIENTS AND METHODS: A total of 8,031 Japanese subjects without medication for gastrointestinal disease were briefly asked about the presence of heartburn, dysphagia, odynophagia, and acid regurgitation by nursing staff before endoscopy for assessment of esophagitis utilizing the Los Angeles Classification. RESULTS: The grade of endoscopic esophagitis was not equivalent to symptoms of dysphagia in 8,031 subjects. We evaluated the characteristics of subjects who complained of only dysphagia. Univariate analysis indicated that non-smoking, and non-drinking females were associated with a higher risk for dysphagia, and multivariate analysis indicated the gender was associated with dysphagia. There was no association of dysphagia with herniation and distribution of age. CONCLUSION: This study indicated that dysphagia was not equivalent to the endoscopic findings according to a brief interview by nursing staff and that dysphagia might be more common in females and those who do not smoke or drink.

Differentiation of gastric surface mucous cells (GSM06) induced by air-liquid interface is regulated partly through mitogen-activated protein kinase pathway.

BACKGROUND AND AIM: The aim of the present study was to examine the role of mitogen-activated protein (MAP) kinase pathway on gastric surface epithelium using an established cell culture model in which differentiation is promoted in GSM06 cells by air-liquid interface. METHODS: A double-dish culture system of mouse gastric surface mucous cell line GSM06 in Ham's F12 medium supplemented with 10% fetal calf serum and 50 microg/mL gentamicin at 37 degrees C in a humidified atmosphere of 5% CO(2) in air was used for an air-liquid interface. Culture cells were examined on histology, cell proliferation was evaluated by bromodeoxy-uridine (BrdU) uptake, and western blot analysis of extracellular signal-regulated kinase (ERK)1/2 and phosphate ERK1/2. On day 3, U0126, an inhibitor of MAP kinase kinase (MEK), was added to medium of incubated cells. RESULTS: GSM06 cells were differentiated with an air-liquid interface for 3 weeks. Compared to immersion control culture, phosphorylated ERK 1/2 expression increased significantly. This increase was completely suppressed with U0126, and tall columnar cells developed by air-liquid interface in GSM06 were not observed in U0126-treated cells. Increase in BrdU uptake with air-liquid interface was suppressed by U0126. CONCLUSION: These results suggested that MAP kinase signaling, activated by air-liquid interface, was, at least in part, related to cell differentiation in GSM06 cells induced by air-liquid interface.

Stress maladjustment in the pathoetiology of ulcerative colitis.

BACKGROUND: The aims of this study were (1) to measure levels of cytokines and stress hormones in ulcerative colitis (UC) patients and determine whether there were any disturbances in the nervous, endocrine, or immune systems, and (2) to measure the ability of UC patients to cope with stress (using a sense of coherence, SOC, test) and their perceived self-efficacy, and to elucidate their response to a stress load. METHODS: We administered questionnaires to and took blood samples from 42 outpatients and eight inpatients whose UC was in remission, and 21 healthy volunteers. In addition, we evaluated blood samples from the inpatients and healthy volunteers following a mental calculation stress test. RESULTS: The questionnaire results revealed that self-efficacy was significantly decreased in the patient groups. Levels of adrenocorticotropic hormone, beta-endorphin and interleukin (IL)-6 were significantly higher in the outpatient than in the control group. IL-6 levels significantly increased following the mental calculation stress test in UC patients compared with in the volunteers. CONCLUSIONS: These results indicate that UC patients (1) have hypersensitive nervous, endocrine, and immune systems, and (2) this hypersensitivity was augmented by the mental calculation stress test.