Enhanced neuron-glia network in the submucosa and increased neuron outgrowth into the mucosa are associated with distinctive expressions of neuronal factors in the colon of rat IBS model.

BACKGROUND: Neuronal attraction and repulsion factors regulate neuron network formation. In the colon of irritable bowel syndrome (IBS), neuron network and enteric glial cells (EGCs) in the submucosa, neuronal outgrowth in the mucosa, and expressions of neuronal factors remain unknown. METHODS: IBS models were prepared by intracolonic injections of acetic acid to Wistar Kyoto (WKY) rats. Using whole-mount submucosal plexus tissue stripped from the distal colon, we examined neuron network, EGC morphology, and localization of both attraction factor (nerve growth factor: NGF) and repulsion factor (semaphorin3A: Sema3A). We evaluated mRNA expressions of NGF and Sema3A in the mucosa and submucosa and neuron outgrowth into the mucosa. KEY RESULTS: In IBS models, nerve fibers were thickened and densely increased in the submucosa remarkably from the outer toward the inner plexus. Submucosal EGCs exhibited process hyperplasia and bulbous swelling of terminals. NGF was predominantly expressed in EGCs than neurons in the submucosa. NGF mRNA expressions were increased in the submucosa in WKY, and their expressions were increased in the mucosa after the injection. Sema3A mRNA expressions were increased in both layers of WKY but tended to be decreased in the mucosa alone after the injection. Neuron outgrowth was increased into the mucosa. NGF was localized at EGCs in the lamina propria mucosae but not mucosal mast cells. CONCLUSIONS & INFERENCES: Neuron network enhancement in the submucosa and neuron outgrowth into the mucosa may be associated with axon guidance factors expressed in hyperplastic EGCs in the colonic submucosa of IBS models.

Tryptase activates enteric glial cells followed by affecting neuronal properties possibly via the stimuli-associated mediators.

OBJECTIVES: Mast cell-derived tryptase causes neuronal elongation/sensitization leading to visceral hypersensitivity. However, effects of tryptase on enteric glial cells (EGCs) and subsequent interaction between EGCs and neurons remain unknown. METHODS: We evaluated proteins and mRNA expressions in EGC (CRL-2690, ATCC) after tryptase stimulation: nerve growth factor (NGF), netrin-1, and glial cell-derived neurotrophic factor (GDNF). We examined morphological changes in neurons (PC12 cells, CRL-1721.1) by co-incubation with the conditioned medium of EGCs after tryptase stimulation. RESULTS: EGC was activated by tryptase, and proliferated (by 1.8-fold) with cytoplasmic expansion and process elongation. Intercellular connections of EGC were more complexed. Tryptase induced mRNA expression (2.5-fold) and protein expression of NGF. Netrin-1 (3-fold) and GDNF (3-fold) mRNA expressions were increased at 30 min. Increase in netrin-1 continued until 6 h, whereas the latter decreased by 3 h. The conditioned medium of EGC after tryptase stimulation expanded neuronal cytoplasm (round or ramified shapes) and neurite outgrowth with elongation of cytoskeletal filaments in time-dependent and dose-dependent manners. These changes were similar to those after NGF stimulation. Growth cone proteins of neurons were also increased by the conditioned medium. CONCLUSION: EGC activated by tryptase changes neuronal morphology (process elongation and cytoplasm expansion) possibly via the stimuli-associated mediators.

Evidence-based clinical practice guidelines for irritable bowel syndrome 2020.

Managing irritable bowel syndrome (IBS) has attracted international attention because single-agent therapy rarely relieves bothersome symptoms for all patients. The Japanese Society of Gastroenterology (JSGE) published the first edition of evidence-based clinical practice guidelines for IBS in 2015. Much more evidence has accumulated since then, and new pharmacological agents and non-pharmacological methods have been developed. Here, we report the second edition of the JSGE-IBS guidelines comprising 41 questions including 12 background questions on epidemiology, pathophysiology, and diagnostic criteria, 26 clinical questions on diagnosis and treatment, and 3 questions on future research. For each question, statements with or without recommendations and/or evidence level are given and updated diagnostic and therapeutic algorithms are provided based on new evidence. Algorithms for diagnosis are requisite for patients with chronic abdominal pain or associated symptoms and/or abnormal bowel movement. Colonoscopy is indicated for patients with one or more alarm symptoms/signs, risk factors, and/or abnormal routine examination results. The diagnosis is based on the Rome IV criteria. Step 1 therapy consists of diet therapy, behavioral modification, and gut-targeted pharmacotherapy for 4 weeks. For non-responders, management proceeds to step 2 therapy, which includes a combination of different mechanistic gut-targeted agents and/or psychopharmacological agents and basic psychotherapy for 4 weeks. Step 3 therapy is for non-responders to step 2 and comprises a combination of gut-targeted pharmacotherapy, psychopharmacological treatments, and/or specific psychotherapy. These updated JSGE-IBS guidelines present best practice strategies for IBS patients in Japan and we believe these core strategies can be useful for IBS diagnosis and treatment globally.

Association between Functional Dyspepsia and Gastric Depressive Erosions in Japanese Subjects.

Objective The association between functional dyspepsia (FD) and endoscopic findings has not been fully elucidated. Helicobacter pylori infection is considered a key factor in the pathophysiology of FD. The Kyoto Classification of Gastritis (KCG) was proposed in 2014 to evaluate endoscopic findings based on the H. pylori status. We investigated the endoscopic findings associated with FD according to the KCG. Methods This cross-sectional study included subjects who underwent esophagogastroduodenoscopy during a medical health check-up. We compared the endoscopic findings between subjects with FD and healthy controls (HCs) according to the KCG. Results A total of 456 subjects were analyzed. Among them, the detection rate of FD was 5.5% (25/456 persons). In a univariate analysis of the endoscopic findings, a significantly lower proportion of subjects with FD had gastric red streak in comparison to HCs (0% vs. 18.6%, respectively; p=0.0124). Subjects with FD were more likely to have gastric depressive erosion (20.0% vs. 7.9%; p=0.0522). A higher proportion of the erosion-positive subjects had FD in comparison to erosion-negative subjects (12.8% vs. 4.8%). There were no significant differences in the other endoscopic findings, including gastric atrophy, intestinal metaplasia, enlarged fold, nodularity, and diffuse redness. A multivariate analysis revealed that gastric depressive erosion was significantly and independently associated with FD (odds ratio, 2.92; 95% confidence interval, 1.03-8.26; p=0.0436). In contrast, gastric red streak was not associated with FD (p=0.989). Conclusion Gastric depressive erosions may be associated with dyspepsia.

[A Case Survived Long Period after Repeated Operation against the Small Intestinal GIST with Perforation].

A patient was 60-year-old man. In March 2011, the small bowel tumor with perforation was found and the partial resection of small intestine was urgently performed. KIT of resected specimen was positive. Then, diagnosis as GIST was defined. Oral administration of imatinib was started, but it was finished in 5 months because of development of the systemic edema. In February 2013, the abdominal CT revealed a tumor of 20 cm in size in the pelvis. Upon laparotomy, we detected the GIST recurrence generated at the region of small intestine anastomosis where manipulated previously, then resected all of tumor and partially small intestine. Afterward, we diagnosed as a recurrence of GIST. In March 2014, the abdominal CT found 4 cm sized mesenteric tumor and 2 cm sized abdominal wall tumor. The laparotomy was performed and we found 5 disseminated nodules intraperitoneally. We confirmed that all of these disseminated nodules were successfully removed. We defined them as re-recurrence of GIST. Six years and 5 months have elapsed since the first operation was performed, but there is no sign of three times recurrence.

Postprandial Symptoms Felt at the Lower Part of the Epigastrium and a Possible Association of Pancreatic Exocrine Dysfunction with the Pathogenesis of Functional Dyspepsia.

Objective In symptom-dependent diseases such as functional dyspepsia (FD), matching the pattern of epigastric symptoms, including severity, kind, and perception site, between patients and physicians is critical. Additionally, a comprehensive examination of the stomach, duodenum, and pancreas is important for evaluating the origin of such symptoms. Methods FD-specific symptoms (epigastric pain, epigastric burning, early satiety, and postprandial fullness) and other symptoms (regurgitation, nausea, belching, and abdominal bloating) as well as the perception site of the above symptoms were investigated in healthy subjects using a new questionnaire with an illustration of the human body. A total of 114 patients with treatment-resistant dyspeptic symptoms were evaluated for their pancreatic exocrine function using N-benzoyl-L-tyrosyl-p-aminobenzoic acid. Results A total of 323 subjects (men:women, 216:107; mean age, 52.1 years old) were initially enrolled. Most of the subjects felt the FD-specific symptoms at the epigastrium, while about 20% felt them at other abdominal sites. About 30% of expressed as epigastric symptoms were FD-nonspecific symptoms. At the epigastrium, epigastric pain and epigastric burning were mainly felt at the upper part, and postprandial fullness and early satiety were felt at the lower part. The prevalence of patients with pancreatic exocrine dysfunction was 71% in the postprandial fullness group, 68% in the epigastric pain group, and 82% in the diarrhea group. Conclusion We observed mismatch in the perception site and expression between the epigastric symptoms of healthy subjects and FD-specific symptoms. Postprandial symptoms were often felt at the lower part of the epigastrium, and pancreatic exocrine dysfunction may be involved in the FD symptoms, especially for treatment-resistant dyspepsia patients.

Concentration of Glial Cell Line-Derived Neurotrophic Factor Positively Correlates with Symptoms in Functional Dyspepsia.

BACKGROUND: In patients with functional dyspepsia (FD), mild duodenal inflammation correlates with increased mucosal permeability. Enteric glial cells can produce glial cell line-derived neurotrophic factor (GDNF) to repair disrupted epithelial barrier function. AIMS: We examined the role of duodenal GDNF in FD pathophysiology and its association with dyspeptic symptoms. METHODS: Duodenal biopsies taken from FD patients and control subjects were used for analysis. GDNF protein expression and localization were examined. Cellular infiltration of eosinophils and mast cells was measured. We also examined the intercellular space between the adjacent epithelial cells at the apical junction complex using transmission electron microscopy. RESULTS: In FD patients, expression of GDNF protein was significantly increased compared with controls, 107.3 (95.3-136.7) versus 49.3 (38.0-72.6) pg/mg protein (median (interquartile range), p = 0.006), respectively. GDNF was localized in enteric glial cells, eosinophils, and epithelial cells. The number of eosinophils was significantly greater in FD patients than in controls, 1039 (923-1181) versus 553 (479-598) cells/mm2 (p = 0.021), respectively. The intercellular space was dilated at the adherent junction in FD patients compared to control patients, 32.4 (29.8-34.8) versus 22.0 (19.9-26.1) nm (p = 0.002), respectively. Intercellular distance positively correlated with the frequency of postprandial fullness and early satiation (p = 0.001, r = 0.837 and p = 0.009, r = 0.693, respectively). Expression of GDNF correlated with epigastric burning (p = 0.041, r = 0.552). CONCLUSIONS: Increased expression of duodenal GDNF might be involved in FD pathophysiology and symptom perception.

Disorder of autonomic nervous system and its vulnerability to external stimulation in functional dyspepsia.

To elucidate the role of autonomic nervous system in functional dyspepsia patients, we examined 24-h heart rate variability: the basal levels, responses after lunch, cold pressor and mental arithmetic tests, and the efficacy of an autonomic drug (tofisopam). The high-frequency component (HF: 0.15-0.40 Hz) and the ratio of HF to the low-frequency component (LF: 0.04-0.15 Hz; LF/HF ratio) were used as indicators of parasympathetic and sympathetic autonomic nervous system function. The HF component in the 24-h, daytime, and nighttime was low in 86.7%, 97.8%, and 66.7% of patients (n = 45) and the LF/HF ratio was high in 51.1%, 73.3%, and 26.6% of patients. Gastrointestinal symptom tended to be severe in patients with autonomic nervous system disorder (p = 0.085). The abnormal response in HF component after lunch occurred in 38.2% (13/34) of patients who revealed a greater tendency towards in indigestion score (p = 0.061). Delays in recovery to the basal autonomic nervous system level after stimulus of the cold pressor and the mental arithmetic tests occurred in parts of patients. Tofisopam partially improved autonomic nervous system dysfunction and abdominal pain/indigestion. Imbalanced autonomic nervous system function and vulnerability for recovery from external stimuli were observed in functional dyspepsia patients, which was associated with dyspeptic symptoms.

Structural changes in gastric glial cells and delayed gastric emptying as responses to early life stress and acute adulthood stress in rats.

AIM: Enteric glial cells (EGCs) modulate colonic motility in a maternal separation model. We aimed to investigate structural changes in gastric EGC and gastric emptying as responses to maternal separation and acute adulthood stress in rats to elucidate the pathophysiological roles of gastric EGC. MAIN METHODS: As a chronic stress, we subjected male Wistar rats to 3h of maternal separation during postnatal days 2-14. As an acute adulthood stress (7weeks of age), we used the 8-h water-immersion method. We morphologically evaluated gastric EGCs using whole-mount longitudinal muscle-myenteric plexus preparations. We analyzed gastric emptying by the phenol red method. KEY FINDING: The area of EGC processes that apparently overlapped with neurons increased according to stress intensity (acute stress, 10.4%; maternal separation, 10.2%; maternal separation plus acute stress, 26.6%; control, 5.0%). Ratios of morphologically changed leaf-like processes to the total processes were 8.1%, acute stress; 10.3%, maternal separation; 4.0%, control. Ratio dramatically increased in the combined stress group (20.5%, p=0.026 vs. control). The mean bulging head area of leaf-like processes in the combined stress group was greater by 6.4µm(2) (control, 2.4µm(2); p=0.042). Gastric emptying in the maternal separation group was gradually delayed (104.1% at 7weeks, 66.7% at 17weeks, and 48.5% at 48weeks; p<0.05, respectively). Gastric emptying in the combined stress group tended to be delayed at 17weeks (45.7% vs. 81% in controls, p=0.066). SIGNIFICANCE: Gastric EGCs exhibited structural changes according to stress intensity, which may be associated with stress-induced dysfunction of the stomach.

[A case of stage IV gastric cancer resected after chemotherapy with capecitabine plus cisplatin].

A 64-year-old woman was diagnosed with Stage IV gastric cancer with lymph node and multiple liver metastases. She was treated with 6 courses of chemotherapy, in 3-week courses, with capecitabine (1,000 mg/m/(2)) plus cisplatin(80 mg/m(2)) administered for 2 weeks, followed by a drug-free week. She underwent curative total gastrectomy with D2 lymph node dissection and reconstruction by using the Roux-en-Y method. The postoperative pathological findings revealed a T3 (SE), N1M1, Stage II B tumor; the tumor was determined to be Grade 1b owing to the chemotherapeutic effect. Postoperatively, only S-1 therapy was administered, because of the development of Grade 3 hand-foot syndrome. The patient is alive 1 year and 8 months after the initial gastrectomy.

[The Outcomes of Laparoscopy-Assisted Surgery in Elderly Patients with Colorectal Carcinoma].

AIM: To evaluate short-term outcomes of laparoscopy-assisted colectomy (LAC) in elderly patients with colorectal carcinoma. METHODS: A total of 289 colorectal cancer patients underwent LAC between 2008 and 2013. They were divided into an elderly group (<80 years of age, group E), and a younger group (<80 years of age, group Y). The treatment results, including the surgery-related factors, the perioperative course, and the pre- and postoperative complications, were retrospectively analyzed. RESULTS: There were 49 patients in group E, and 240 patients in group Y. There was no significant difference between the 2 groups considering the operative time, blood loss, rate of transfusion, post-operative hospital stay, rate of conversion to open surgery, or rate of complications, except for the number of patients with an ASA classification of greater than Grade 2 and the degree of lymph node dissection. CONCLUSIONS: LAC in elderly patients was found to be relatively safe because it was associated with a reduction in damage to the abdominal wall, and with an early recovery from surgery. These results suggest that the indications of LAC could be expanded for elderly patients.

High prevalence of gastroesophageal reflux symptoms in patients with non-alcoholic fatty liver disease associated with serum levels of triglyceride and cholesterol but not simple visceral obesity.

BACKGROUND/AIMS: Visceral obesity is commonly involved in the pathogenesis of gastroesophageal reflux disease (GERD) and non-alcoholic fatty liver disease (NAFLD). However, other characteristic factors different from visceral obesity are associated with the pathogenesis of NAFLD. We investigated the prevalence of GERD symptoms in patients with NAFLD and its associated risk factors. METHODS: NAFLD (n = 96) and controls (n = 139) were enrolled in this study. GERD symptoms were evaluated by using a frequency scale for the symptoms of GERD. RESULTS: GERD symptom score and its prevalence rate were higher in the NAFLD group (7.4 ± 0.7, 37%) than those seen in the control groups (4.5 ± 0.4, 20%), which was independent of sex, age, and body mass index (BMI). GERD symptoms were correlated with insulin resistance (r = 0.167, p = 0.011), total cholesterol (T-CHO) (r = 0.138, p = 0.034), triglyceride (TG) (r = 0.178, p = 0.006), or immunoreactive insulin (r = 0.173, p = 0.008) but not BMI (r = 0.089, p = 0.175). GERD symptoms of the NAFLD group were significantly severer in the higher group of T-CHO and TG levels than those in the lower group. Multivariate analysis proved that risk factors related to GERD symptoms were TG (OR 3.96, 95% CI 1.31-11.9) and T-CHO (OR 3.39, 95% CI 1.11-10.3). CONCLUSION: The severity and prevalence of GERD symptoms in patients with NAFLD were high, which was associated with serum levels of TG and T-CHO but not BMI.

[Efficacy of prostaglandin derivatives and mucoprotective drugs in treatment and prevention for NSAIDs-induced ulcer].

Deficiency of prostaglandins (PGs) by non-steroidal anti-inflammatory drugs (NSAIDs) causes a loss of gastroduodenal mucosal integrity, leading to development of ulceration. PG derivatives such as misoprostol and enprostil have been proven effective in prevention and treatment of NSAIDs-induced gastroduodenal ulcers. Although side effects such as diarrhea limit the use of PG derivatives, the efficacy of these drugs in NSAIDs-induced injuries is approximately equal to that of proton pump inhibitors. Mucoprotective drugs such as rebamipide also have been reported to be effective for prevention of NSAIDs-induced ulcers. Since misoprostol and some mucoprotective drugs can prevent NSAIDs-induced small intestinal injuries, these drugs, especially misoprostol, should be used as first-line therapy for NSAIDs-induced gastrointestinal injuries with attention paid to the side effects.

Arachidonic acid peroxides induce apoptotic Neuro-2A cell death in association with intracellular Ca(2+) rise and mitochondrial damage independently of caspase-3 activation.

The present study aimed at understanding the effects of arachidonic acid peroxides on neuronal cell death using the mouse neuroblastoma cell line, Neuro-2A cells. Arachidonic acid peroxides were produced by ultraviolet (UV) radiation. UV-radiated arachidonic acid significantly reduced Neuro-2A cell viability at concentrations of more than 0.1 muM, with being more potential than non-radiated arachidonic acid. Nuclei of Neuro-2A cells killed with UV-radiated arachidonic acid were reactive to Hoechst 33342, a marker of apoptosis, and the effect was much greater than that achieved with non-radiated arachidonic acid. UV-radiated arachidonic acid persistently increased intracellular Ca(2+) concentrations and dissipated mitochondrial membrane potential in Neuro-2A cells. UV-radiated arachidonic acid-induced Neuro-2A cell death, whereas it was not affected by a pancaspase inhibitor or a caspase-3 inhibitor, was significantly inhibited by an inhibitor of caspase-1, -8, or -9. The results of the present study suggest that arachidonic acid peroxides induce apoptotic neuronal cell death in association with intracellular Ca(2+) rise and mitochondrial damage, in part via a caspase-dependent pathway regardless of caspase-3.