Yuka Endo

Effect of a corticotropin releasing hormone receptor antagonist on colonic sensory and motor function in patients with irritable bowel syndrome

Background and aims: Corticotropin releasing hormone (CRH) is a major mediator of the stress response in the brain-gut axis. Irritable bowel syndrome (IBS) is presumed to be a disorder of the brain-gut link associated with an exaggerated response to stress. We hypothesised that peripheral administration of α-helical CRH (αhCRH), a non-selective CRH receptor antagonist, would improve gastrointestinal motility, visceral perception, and negative mood in response to gut stimulation in IBS patients. Methods: Ten normal healthy subjects and 10 IBS patients, diagnosed according to the Rome II criteria, were studied. The tone of the descending colon and intraluminal pressure of the sigmoid colon were measured at baseline, during rectal electrical stimulation (ES), and at recovery after administration of saline. Visceral perception after colonic distension or rectal ES was evaluated as threshold values on an ordinate scale. The same measurements were repeated after administration of αhCRH (10 μg/kg). Results: ES induced significantly higher motility indices of the colon in IBS patients compared with controls. This response was significantly suppressed in IBS patients but not in controls after administration of αhCRH. Administration of αhCRH induced a significant increase in the barostat bag volume of controls but not in that of IBS patients. αhCRH significantly reduced the ordinate scale of abdominal pain and anxiety evoked by ES in IBS patients. Plasma adrenocorticotropic hormone and serum cortisol levels were generally not suppressed by αhCRH. Conclusion: Peripheral administration of αhCRH improves gastrointestinal motility, visceral perception, and negative mood in response to gut stimulation, without affecting the hypothalamo-pituitary-adrenal axis in IBS patients.

Patients and nonconsulters with irritable bowel syndrome reporting a parental history of bowel problems have more impaired psychological distress

Little is known about the prevalence and risk factors for development of irritable bowel syndrome (IBS) in Japan. In the United States, it is reported that heredity and social learning contribute to the development of IBS. Our aims were (1) to estimate the prevalence of IBS, (2) to confirm that subjects with IBS are more likely to have parents with a history of bowel problems, (3) to confirm that gastroenteritis is a risk factor for IBS, and (4) to determine whether these two risk factors interact with psychological distress. Prevalence was estimated from a sample of 417 young adults seen for annual health screening examinations. To evaluate risk factors related to consulting physicians, the 46 subjects who fulfilled Rome II diagnostic criteria for IBS but denied ever having seen a physician about these symptoms (IBS non-consulters) were compared to the 317 subjects who did not meet the criteria for IBS (controls) and to a group of 56 patients diagnosed with IBS by gastroenterologists (IBS patients). All subjects completed the Gastrointestinal Symptoms Rating Scale, the State-Trait Anxiety Inventory, the Self-Rating Depression Scale, the Perceived Stress Scale, and the SF-36 quality of life scale. Fourteen and two-tenths percent (15.5% of females and 12.9% of males) of the community sample met the criteria for IBS diagnosis, of whom 22% consulted physicians. IBS patients and IBS nonconsulters were more likely than controls to have a parental history (33.9 vs. 12.6%, P < 0:001, for patients and 26.1 vs. 12.6%, P < 0:01, for nonconsulters) and were more likely to report an infective history compared to controls (44.6 vs. 16.1%, P < 0:001, for patients and 32.6 vs. 16.1%, P < 0:01, for nonconsulters). Two-way analysis of variance showed that the parental history was associated with a significantly greater impact on symptoms of indigestion, diarrhea, constipation, state and trait anxiety, and the SF-36 scales for social functioning and role emotional and that an infective history was associated with a greater impact on bodily pain. Both a parental history of bowel problems and a history of acute gastroenteritis are significant risk factors for development of IBS in Japan, as reported for the United States. Moreover, patients with such a family history show more psychological distress than other patients.

Impact of serotonin transporter gene polymorphism on brain activation by colorectal distention.

BACKGROUND AND AIMS Determining the gene that plays a key role in brain-gut interactions is a crucial step for clarifying the pathophysiology of irritable bowel syndrome (IBS). We previously reported that the 5-hydroxytryptamine transporter gene-linked polymorphic region (5-HTTLPR) is related to anxiety in subjects with IBS. The amygdala is more activated during fearful face recognition in individuals with the s allele of 5-HTTLPR. Here, we tested our hypothesis that 5-HTTLPR differentially activates brain regions with colorectal distention in humans. METHODS We enrolled 28 subjects without any organic disease. The study was approved by the Ethics Committee and all subjects gave written informed consent. DNA was extracted from the peripheral blood. The genotype of 5-HTTLPR was determined using polymerase chain reaction. Age, sex, diagnosis-matched individuals with the s/s genotype (n=14) and individuals with the l allele (genotypes l/s, l/l, l/extra-l, n=14) were compared. A barostat bag was inserted to the colorectum and was intermittently inflated with no (0 mm Hg), mild (20 mm Hg), or intense (40 mm Hg) stimulation on a random order. Radioactive H2[(15-)O] saline was injected at bag inflation and then positron emission tomography was performed. Changes in rCBF were analyzed using statistical parametric mapping. RESULTS Individuals with the s/s genotype showed a significantly larger increase in rCBF by colorectal distention from 0 mm Hg to 40 mm Hg than individuals with the l allele. The significantly more activated brain regions in individuals with the s/s genotype were the left anterior cingulate cortex and right parahippocampal gyrus (p<0.0001). The increase in rCBF by colorectal distention of 20 mm Hg compared with 0 mm Hg was significantly larger in the left orbitofrontal cortex of individuals with the s/s genotype than that of individuals with the l allele (p<0.0001). CONCLUSION These data suggest that individuals with a weak function of serotonin transporter respond to gut signals more in emotion-regulating brain regions. Functional gene polymorphism may partially predict the individual effect of a selective serotonin reuptake inhibitor on visceral pain.

Exaggerated motility of the descending colon with repetitive distention of the sigmoid colon in patients with irritable bowel syndrome

Background. Visceral hypersensitivity is one of the mechanisms of irritable bowel syndrome (IBS), but it does not explain the entire symptomatology, i.e., altered bowel habit with abdominal pain relieved by defecation. We tested our hypothesis that an abnormal link between luminal stimulation and mural response may have some role in the pathophysiology of IBS. Methods. Patients with IBS (n = 10, median 21 years old, 5 male patients, 5 female patients) and healthy control subjects (n = 10, median 21 years old, 5 men, 5 women) were studied. A manometric catheter with three transducers was inserted to the descending colon and a balloon was placed in the distal sigmoid colon. Another catheter with three transducers was inserted to the duodenum. After baseline for 30 min, the sigmoid colon was stimulated by balloon distention for 30 min followed by recovery for 30min. Balloon distention was repeated 100 times, and each stimulation consisted of a 5-s inflation and a 10-s deflation, with a volume of 50 ml maximum. The sensory threshold of balloon inflation was then examined, and plasma adrenocorticotropic hormone (ACTH) was measured with radioimmunoassay. Results. Repetitive colonie distention induced a significant increase in motility indices (mmHg s/s%) of the descending colon in the IBS patients (from 118 ± 25 to 333 ± 108, P < 0.05) but not of those in controls (from 90 ± 16 to 89 ± 19). A significant group difference (P < 0.05), period effect (P < 0.02), and group X period interactions (P < 0.01) were detected with two-way ANOVA. Duodenal motility indices in controls were significantly reduced by colonic distention (from 169 ± 25 to 104 ± 14, P < 0.01), but those in the IBS patients were not (from 156 ± 17 to 124 ± 20). The sensory threshold of balloon inflation in the IBS patients (74 ± 10 ml) was significantly lower than that in controls (125 ± 6 ml, P < 0.001). There was no significant difference in plasma ACTH levels between the IBS patients and controls. Conclusions. Repetitive distention of the distal sigmoid colon below the sensory threshold induced orad exaggerated motility of the colon in IBS patients. The distention inhibited motility of the small intestine in healthy subjects, but this inhibition was blunted in IBS patients. These results suggest that IBS patients may have not only visceral hypersensitivity, but also an abnormal intestinal reflex.

Translation and validation of a Japanese version of the irritable bowel syndrome-quality of life measure (IBS-QOL-J).

AimsTo compare quality of life (QOL) for patients with irritable bowel syndrome (IBS) between the U.S. and Japan, it is indispensable to develop common instruments. The IBS-QOL, which is widely used in Western countries, was translated into Japanese as there has been a lack of Japanese disease-specific QOL measures for IBS.MethodsThe original 34 items of the IBS-QOL were translated from English into Japanese through two independent forward translations, resolution, back translation, and resolution of differences. Forty nine patients who had GI symptoms but did not have any organic diseases (including 30 IBS patients diagnosed by Rome II criteria) were recruited from Tohoku University Hospital in Sendai, Japan and completed a Japanese version of the IBS-QOL (IBS-QOL-J) concomitant with a Japanese version of the IBS severity index (IBSSI-J) twice within 7–14 days.ResultsThe IBS-QOL-J demonstrated high internal consistency (Cronbachs alpha; 0.96) and high reproducibility (intraclass correlation coefficient; 0.92, p < 0.001). Convergent analyses confirmed that the overall score of IBS-QOL-J was significantly correlated with overall severity of IBS symptoms on the IBSSI-J (r = -0.36, p = 0.01) and with the individual items on the IBSSI-J that assess interference with life in general (r = -0.47, p = 0.001) and dissatisfaction with bowel habits (r = -0.32, p < 0.05). Eight patients who reported continuous abdominal pain in the past 6 months had significantly lower scores in the IBS-QOL-J than those who did not (53.7 +- 12.7 vs. 73.6 +- 19.5, p < 0.01). Age, sex, education or marital status did not affect scores on the measure.ConclusionThe IBS-QOL-J is a reliable instrument to assess the disease-specific QOL for IBS. Considering cross-cultural comparison, this measure is likely to be a valuable tool to investigate the QOL in Japanese patients with IBS.

Validation of the Japanese version of the Rome II modular questionnaire and irritable bowel syndrome severity index

BackgroundInstruments for measuring the presence and severity of specific irritable bowel syndrome (IBS) symptoms, comparable to those used in Western countries, have been lacking in Japan. The aim of this study was to develop, validate, and confirm the reliability of the Japanese version of the Rome II modular questionnaire for IBS (RIIMQ-J) and the IBS severity index (IBSSI-J).MethodsForty-nine patients in the university hospital with chronic or recurrent abdominal pain and discomfort and/or altered bowel habits were enrolled. With Rome II criteria, 27 patients were diagnosed as having IBS, and the other 22 patients were evaluated as having other functional bowel disorders (FBDs). The English versions of RIIMQ and IBSSI were translated into Japanese. After back-translation and approval of the questionnaire, subjects completed both questionnaires twice within 14 days.ResultsCronbachs alpha of the RIIMQ-J was high (0.72). The sensitivity of RIIMQ-J for the diagnosis of IBS was also high (89%). The specificity of RIIMQ-J for denial of IBS among patients with other FBD was satisfactory (73%). The IBSSI-J showed high internal consistency (0.69) and reproducibility (intraclass correlation coefficient, 0.86, P < 0.001).ConclusionsThe RIIMQ-J and IBSSI-J are valid, reliable, and appropriate instruments for detecting and assessing the severity of IBS status in Japanese patients.

Increased brain histamine H1 receptor binding in patients with anorexia nervosa.

BACKGROUND The central histaminergic neuron system modulates various brain functions, including eating behavior. We hypothesized that women have higher density of histamine H1 receptor (H1R) in the limbic system than men and that the density of central H1R is increased in patients with anorexia nervosa (AN). METHODS Subjects were 12 female AN patients, 12 healthy female subjects, and 11 healthy male subjects. Positron emission tomography with H1R radioligand [(11)C]doxepin was performed on all subjects and regions of interest based analysis was conducted to evaluate brain H1R binding potential (BP). Abnormal eating behavior, depression, and anxiety of subjects were evaluated using the Eating Attitude Test-26 (EAT-26), Self-Rating Depression Scale (SDS), and State-Trait Anxiety Inventory (STAI), respectively. RESULTS Binding potential of [(11)C]doxepin in female subjects was significantly higher than that in male subjects at the following brain sites: amygdala, hippocampus, medial prefrontal cortex, orbitofrontal cortex, and temporal cortex. Anorexia nervosa patients showed significantly higher BP of [(11)C]doxepin in the amygdala and lentiform nucleus than the control female subjects. In AN patients, BP of [(11)C]doxepin in the amygdala and thalamus negatively correlated with EAT-26 scores. There was a significant negative correlation between BP of [(11)C]doxepin and SDS or STAI scores in the amygdala, anterior cingulate cortex, and orbitofrontal cortex of AN patients. CONCLUSIONS These findings support the hypothesis that women have higher H1R density in the limbic system than men and suggest that AN patients may have higher expression of H1R in the limbic brain, particularly in the amygdala.

The features of adolescent irritable bowel syndrome in Japan.

Objective and Background:  The onset of IBS is in adolescence in many cases. However, the features of adolescent IBS were generally lacking. The objective of this research was to know the features of adolescent IBS in Japan.

Immunoglobulin G4-related gastrointestinal diseases, are they immunoglobulin G4-related diseases

In immunoglobulin G4 (IgG4)-related disease (RD), organ enlargement or nodular lesions consisting of abundant infiltration of lymphocytes and IgG4-positive plasma cells and fibrosis are seen in various organs. Although infiltration of many IgG4-positive plasma cells is detected in the gastric and colonic mucosa and major duodenal papilla of patients with autoimmune pancreatitis, it cannot be diagnosed as a gastrointestinal lesion involved in IgG4-RD, because none of the following is observed in these lesions: a mass-like formation; dense fibrosis; or obliterative phlebitis. Based on our review of the literature, there appear to be two types of IgG4-related gastrointestinal disease. One is a gastrointestinal lesion showing marked thickening of the wall of the esophagus and stomach, consisting of dense fibrosis with abundant infiltration of IgG4-positive plasma cells, which usually show submucosal spreading. The other is an IgG4-related pseudotumor occurring in gastrointestinal regions such as the stomach, colon, and major duodenal papilla, showing polypoid or mass-like lesions. Most solitary IgG4-related gastrointestinal lesions that are not associated with other IgG4-RD appear to be difficult to diagnose. It is of utmost importance to rule out malignancy. However, these lesions may respond to steroid therapy. To avoid unnecessary resection, IgG4-related gastrointestinal diseases should be considered in the differential diagnosis.

Primary care in the treatment of functional gastrointestinal symptoms in Japan: prescription preferences and impression of results.

Background : Functional gastrointestinal (GI) disorders are common in primary care. However, proper pharmacological approaches have not yet been established. The reason for a lack of proper approaches may be attributable to the lack in clarity of their pathogenesis and pathophysiology. Meta‐analysis of pharmacological approaches to functional GI disorders failed to identify the solid cluster of patients’ symptoms.