Sayuri Yamamoto, Yurika Kawamura, Kazuhiro Yamamoto, Yoshiharu Yamaguchi, Yasuhiro Tamura, Shinya Izawa, Hiroaki Nakagawa, Yoshinori Wakita, Yasutaka Hijikata, Masahide Ebi, Yasushi Funaki, Wataru Ohashi, Naotaka Ogasawara, Makoto Sasaki, Masato Maekawa, and Kunio Kasugai. J Neurogastroenterol Motil 2021;27:602-11. https://doi.org/10.5056/jnm20135

Background In Japan, the prevalence of constipation-predominant irritable bowel syndrome (IBS-C) and functional constipation (FC) diagnosed by the Rome III criteria is unclear, as are the demographic profile, quality of life (QOL), and habits of persons with IBS-C or FC. Methods We performed an internet survey of constipation. After extracting 3000 persons fitting the composition of the general Japanese population, we investigated demographic factors, lifestyle, defecation, and laxatives. IBS-C and FC were diagnosed by Rome III criteria. Respondents also completed the Japanese IBS severity index (IBS-SI-J), Japanese IBS QOL scale (IBS-QOL-J), SF-8, Hospital Anxiety and Depression Scale (HADS), and Japanese Health Practice Index (JHPI). Results There were 262 respondents with FC (8.73%) [73 men and 189 women; mean age: 49.8 ± 13.1 years; mean body mass index (BMI): 21.0 ± 3.3 g/m²] and 149 respondents with IBS-C (4.97%) (76 men and 73 women; mean age; 41.6 ± 13.7 years; mean BMI: 20.8 ± 3.0 kg/m²). Total IBS-QOL-J score were significantly lower in the IBS-C group than the FC group. With regard to SF-8, score of mental component summary (MCS) was significantly lower in the IBS-C group. The total IBS-SI-J score and item scores, except for satisfactory defecation, were significantly higher in the IBS-C group than the FC group. HADS showed a significant increase of anxiety and depression in both the groups, and the JHPI revealed insufficient sleep. Conclusions In Japan, among the population of under 70 years old, the prevalence of IBS-C and FC (Rome III criteria) was 4.97% and 8.76%, respectively. IBS-C caused more severe symptoms than FC, resulting in impairment of QOL.

Palatal fusion is a critical step during palatogenesis. In this fusing interface, the epithelial sheets need to be removed in order to achieve mesenchymal continuity. Epithelial cellular migration is one of the possible mechanisms, and live imaging of the labeled epithelium could provide direct evidence for it. However, the removal of medial edge epithelium (MEE) between the bilateral processes takes place in the middle of the dorso-ventral axis of the palatal shelf, and thus it is challenging to capture the cellular behavior directly. Here, we evaluate cellular behavior of MEE cells using a live imaging technique with a mouse model which expresses GFP under the promoter of Keratin14 (K14-GFP) and unpaired palatal shelf culture. Using this approach, we successfully obtained live images of epithelial behavior and detected epithelial cell migration on the surface of the secondary palatal shelf without touching of the opposing shelf. Additionally, the pattern of epithelial elimination resulted in oval-shaped exposed mesenchyme, which recapitulated the situation during secondary palate fusion in vivo. Detailed image processing revealed that most of the MEE migrated in an outward direction at the boundary regions as the oval shape of the exposed mesenchyme expanded. The migration was preceded by the bulging of MEE, and disappearance of GFP signals was not evident in bulging or migrating MEE at the boundary regions. Furthermore, the MEE migration and the subsequent mesenchymal exposure were disturbed by application of ROCK inhibitor. Together, these findings indicated that epithelial cell migration contributed importantly to the MEE removal and the subsequent exposure of the underlying mesenchyme. Furthermore, they indicated that the migration of epithelial cells was regulated in a time- and space-specific manner, since unpaired palatal shelf culture exhibited these cellular behaviors even in the absence of the opposing shelf. Altogether, present data indicated that this new experimental system combining live imaging with GFP-labeled epithelium mice and unpaired palatal shelf culture enabled direct visualization of cellular migration of MEE in vitro and could be a powerful tool to investigate its cellular and molecular mechanisms.

Background: Functional constipation (FC), a functional bowel disorder with symptoms of constipation, has considerable impact on quality of life. As data regarding its prevalence and epidemiology are lacking, this study aimed to evaluate the prevalence, population composition, lifestyle, quality of life, and clinical characteristics of these individuals by comparing people with and without FC. These parameters were also compared among individuals with strong and weak awareness of constipation. Methods: An internet survey was conducted among 10,000 individuals aged 20–69 years from the general Japanese population; they were registered with an internet survey company. The following data were obtained: age, sex, educational history, occupation, residence, history of other diseases, lifestyle (including smoking/drinking habits using the Japanese Health Practice Index, medication use, symptoms of constipation according to the Rome III criteria, stool types according to the Bristol stool scale, and use of laxatives, including the place of purchase and cost per month or acceptable cost per month. The 8-item Short Form Health Survey Questionnaire was also used; FC was diagnosed based on Rome III criteria. All respondents were classified according to their awareness of constipation (i.e. strong or weak), and their characteristic features were compared. Results: The data of 3000 respondents were evaluated; 262 (8.7%) had FC, which was common among older adults, women, and homemakers. FC was associated with changes in the frequency of bowel movement, sensation of incomplete or scanty evacuation, and the use of manual maneuvers; these are consequential clinical symptoms of FC. These individuals frequently skipped breakfast, had insufficient sleep, had more severe constipation, and had purchased laxatives in pharmacies or online more often than those without FC. A strong awareness of constipation was significantly more prevalent among women and homemakers. A history of anemia and cardiovascular disease was significantly more frequent in the strong awareness group, whereas a history of hypertension was more frequent in the weak awareness group. Conclusions: Appropriate and comprehensive management should be provided for FC, based on the understanding of its characteristic features and considering the symptoms and lifestyle.

Background: There has been an increasing interest in low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diets for irritable bowel syndrome. The aims of the present study were (1) to survey knowledge and eating habits with respect to low- and high-FODMAP foods in a general population, and (2) to analyze the relationship between lower gastrointestinal problems (LGIP, pain and irregular stool habits) and habits/foods for prevention. Methods: The present study was carried out with medical examinees (n = 1024) at a clinic in Japan using self-administrated questionnaires. The subjects were asked whether they knew each FODMAP food, eating habit, and cooking habit. Chi-squared tests were used for analyzing the characteristics of LGIP-related factors. Logistic regression models were utilized to select foods which predict LGIP. Results: Women cooking by themselves and who were younger indicated less LGIP (Chai-square for trend). More than 60% reported that they often ate rice, coffee, eggs, pork, chicken, breads, noodles, and onions, which are solely classified as high-FODMAP foods. LGIP was related to age and self-cooking habits in women. Soybeans had the least significant relationship with LGIP (odds ratio (OR) 0.48, 95% confidence interval (CI) 0.32–0.73), followed by seaweed, shellfish, wheat, cow’s milk, green beans, and cauliflower. In contrast, artificial sweeteners were most significantly related with LGIP (OR 1.54, 95% CI 1.16–2.03), followed by margarine and tomato paste. Conclusions: The associations between FODMAP foods and LGPI appeared to be different from the Western results. Furthermore, some diets related to LGIP are suggested.

Background: Constipation causes substantial morbidity worldwide. Methods: This survey assessed constipation-related factors in Japan using the Japanese version of the Irritable Bowel Syndrome Quality of Life (IBS-QOL-J) instrument. We also examined the relationship among laxative type, Bristol Stool Form Scale (BSFS) scores, and treatment cost. Finally, we examined differences in satisfaction scores according to laxative type, treatment type, treatment cost, and BSFS score. Results: IBS-QOL-J was higher among those taking salt and/or irritation laxatives. Those paying >JPY 5000 (USD 50.00) had the lowest IBS-QOL-J. IBS-QOL-J was significantly lower among those with a BSFS score of 1 or 2 (severe constipation). Conclusions: This study’s findings suggest that a variety of factors, including treatment type and cost, are associated with defecation satisfaction. Those who had hard stools, used multiple laxatives, or spent more on treatment were less satisfied. Future strategies should target therapies that do not require multiple laxatives with lower treatment costs. Adequate defecation with a small number of appropriate laxatives at minimal cost appears to improve defecation satisfaction. It is desirable to identify appropriate laxatives and improve dietary habits and exercise routines. It is also necessary to stop blindly increasing laxative usage and properly diagnose constipation disorders such as anatomical abnormalities other than functional constipation.