Central serotonergic and noradrenergic receptors in functional dyspepsia

Beta 3-adrenoceptor agonism ameliorates early-life stress-induced visceral hypersensitivity in male rats

Visceral hypersensitivity, a hallmark of disorders of the gut-brain axis, is associated with exposure to early-life stress (ELS). Activation of neuronal β3-adrenoceptors (AR) has been shown to alter central and peripheral levels of tryptophan and reduce visceral hypersensitivity. In this study, we aimed to determine the potential of a β3-AR agonist in reducing ELS-induced visceral hypersensitivity and possible underlying mechanisms. Here, ELS was induced using the maternal separation (MS) model, where Sprague Dawley rat pups were separated from their mother in early life (postnatal day 2-12). Visceral hypersensitivity was confirmed in adult offspring using colorectal distension (CRD). CL-316243, a β3-AR agonist, was administered to determine anti-nociceptive effects against CRD. Distension-induced enteric neuronal activation as well as colonic secretomotor function were assessed. Tryptophan metabolism was determined both centrally and peripherally. For the first time, we showed that CL-316243 significantly ameliorated MS-induced visceral hypersensitivity. Furthermore, MS altered plasma tryptophan metabolism and colonic adrenergic tone, while CL-316243 reduced both central and peripheral levels of tryptophan and affected secretomotor activity in the presence of tetrodotoxin. This study supports the beneficial role of CL-316243 in reducing ELS-induced visceral hypersensitivity, and suggests that targeting the β3-AR can significantly influence gut-brain axis activity through modulation of enteric neuronal activation, tryptophan metabolism, and colonic secretomotor activity which may synergistically contribute to offsetting the effects of ELS.

A study of the therapeutic mechanism of Jakyakgamcho-Tang about functional dyspepsia through network pharmacology research

Herbal medicines have traditionally been used as an effective digestive medicine. However, compared to the effectiveness of Herbal medicines, the treatment mechanism has not been fully identified. To solve this problem, a system-level treatment mechanism of Jakyakgamcho-Tang (JGT), which is used for the treatment of functional dyspepsia (FD), was identified through a network pharmacology study. The two components, paeoniae radix alba and licorice constituting JGT were analyzed based on broad information on chemical and pharmacological properties, confirming 84 active chemical compounds and 84 FD-related targets. The JGT target confirmed the relationship with the regulation of various biological movements as follows: cellular behaviors of muscle and cytokine, calcium ion concentration and homeostasis, calcium- and cytokine-mediated signalings, drug, inflammatory response, neuronal cells, oxidative stress and response to chemical. And the target is enriched in variety FD-related signaling as follows: MAPK, Toll-like receptor, NOD-like receptor, PI3K-Akt, Apoptosis and TNF signaling pathway. These data give a new approach to identifying the molecular mechanisms underlying the digestive effect of JGT.

Resveratrol Modulates the Gut-Brain Axis: Focus on Glucagon-Like Peptide-1, 5-HT, and Gut Microbiota

Resveratrol is a natural polyphenol that has anti-aging and anti-inflammatory properties against stress condition. It is reported that resveratrol has beneficial functions in various metabolic and central nervous system (CNS) diseases, such as obesity, diabetes, depression, and dementia. Recently, many researchers have emphasized the connection between the brain and gut, called the gut-brain axis, for treating both CNS neuropathologies and gastrointestinal diseases. Based on previous findings, resveratrol is involved in glucagon-like peptide 1 (GLP-1) secreted by intestine L cells, the patterns of microbiome in the intestine, the 5-hydroxytryptamine (5-HT) level, and CNS inflammation. Here, we review recent evidences concerning the relevance and regulatory function of resveratrol in the gut-brain axis from various perspectives. Here, we highlight the necessity for further study on resveratrol's specific mechanism in the gut-brain axis. We present the potential of resveratrol as a natural therapeutic substance for treating both neuropathology and gastrointestinal dysfunction.

Expression of tryptophan hydroxylase in gastric mucosa in symptomatic and asymptomatic Helicobacter pylori infection

INTRODUCTION

Helicobacter pylori infection induces clinical symptoms in 15-20% of subjects, and the reason for this variation is still not clear. The aim of the present study is to evaluate the expression of tryptophan hydroxylase (TpH-1) in gastric mucosa of patients with symptomatic and asymptomatic H. pylori infection in relation to the intensity of bacterial colonization and severity of dyspeptic symptoms.

MATERIAL AND METHODS

Ninety subjects (aged 35-49 years) were enrolled in the study and separated into 3 groups of 30 subjects each. Group I - healthy volunteers without H. pylori infection, group II - subjects with asymptomatic H. pylori infection, group III - H. pylori-infected patients with dyspeptic symptoms, mainly fasting and nocturnal epigastric pain. To diagnose H. pylori infection the urea breath test (UBT-13C) and histological analysis were performed. The level of mRNA expression of tryptophan hydroxylase (TpH-1) was estimated in gastric mucosa with RT-PCR.

RESULTS

The expression of this enzyme in antral mucosa was 2.69 ±0.97 in group I, 2.28 ±0.69 in group II (p > 0.05) and 4.40 ±1.64 in group III (p < 0.001). The levels of expression of TpH-1 in gastric body mucosa were 2.16 ±0.70, 1.57 ±0.52 (p > 0.05) and 3.40 ±1.51 (p < 0.001), respectively. In group III a positive correlation was found between intensity of H. pylori colonization and TpH-1 expression as well as between TpH-1 expression and severity of dyspeptic symptoms.

CONCLUSIONS

Increased expression of TpH-1 in gastric mucosa plays a role in pathogenesis of chronic dyspepsia.

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.

Depression and Dyspepsia: An Implication of Islamic Resources

Depression is a common mental disorder and the leading cause of disability in the worldwide. Based on Islamic resources, indigestion and dyspepsia can lead to depression. In modern medicine, though many somatic diseases have been named as possible causes of depression, the effect of gastrointestinal disorders on depression is still an enigma. Therefore, the focus of this study is to explore the available scientific literature of modern medicine in order to find the footprint of effect of indigestion on depression. In this study, related articles were retrieved from PubMed, Ovid, Proquest and Magiran databases by using the Medical Subject Heading keywords "depression," "psychology," "dyspepsia" and "gastrointestinal diseases." In the next step, studies, which are exactly confirm the Islamic viewpoint, were selected from the retrieved articles. Only one prospective study in 2012 has stated that people with functional gastrointestinal disorders and without elevated levels of anxiety and depression at baseline had significantly higher levels of anxiety and depression at 12-year follow-up. Based on Islamic viewpoint, indigestion can lead to depression, but this aspect approved by only one 12-year prospective population-based study in our review. It seems that it is necessary to conduct complementary studies investigating this hypothesis.

The Role of H. pylori CagA in Regulating Hormones of Functional Dyspepsia Patients

Helicobacter pylori (H. pylori, Hp) colonizes the stomachs of approximately 20%–80% of humans throughout the world. The Word Healthy Organization (WHO) classified H. pylori as a group 1 carcinogenic factor in 1994. Recently, an increasing number of studies has shown an association between H. pylori infection and various extragastric diseases. Functional dyspepsia (FD) is considered a biopsychosocial disorder with multifactorial pathogenesis, and studies have shown that infection with CagA-positive H. pylori strains could explain some of the symptoms of functional dyspepsia. Moreover, CagA-positive H. pylori strains have been shown to affect the secretion of several hormones, including 5-HT, ghrelin, dopamine, and gastrin, and altered levels of these hormones might be the cause of the psychological disorders of functional dyspepsia patients. This review describes the mutual effects of H. pylori and hormones in functional dyspepsia and provides new insight into the pathogenesis of functional dyspepsia.

Anethole restores delayed gastric emptying and impaired gastric accommodation in rodents

Functional dyspepsia (FD), a functional gastrointestinal disorder, is characterized by persistent or recurrent postprandial upper abdominal discomfort and epigastric pain. The high prevalence of FD and associated healthcare costs suggests that treatment of this condition by methods other than prescribed medicines, such as natural products, could be beneficial. Delayed gastric emptying and impaired gastric accommodation play important roles in the development of FD. Anethole (1-methoxy-4-((E)-propenyl)-benzene), a major component of essential fennel oil, has been used as a flavoring, in alcoholic beverage production and in pharmaceutical formulations for many years. In this study, we examined the effects of anethole on delayed gastric emptying and impaired gastric accommodation in rodents. Oral administration of anethole improved clonidine-induced delayed gastric emptying but did not affect normal gastric emptying in mice. Fennel oil and Anchu-san (a Japanese herbal medicine containing anethole) also restored delayed gastric emptying. Furthermore, oral administration of anethole stimulated gastric accommodation in rats. These results suggest that anethole could be beneficial for the treatment of FD.

Genetics and pharmacogenetics of aminergic transmitter pathways in functional gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) are highly prevalent syndromes, without evident underlying organic causes. Their pathogenesis is multifactorial in nature, with a combination of environmental and genetic factors contributing to their clinical manifestations, for which most of current treatments are not satisfactory. It is acknowledged that amine mediators (noradrenaline, dopamine and serotonin) play pivotal regulatory actions on gut functions and visceral sensation. In addition, drugs of therapeutic interest for FGIDs act on these transmitter pathways. The present article reviews current knowledge on the impact of genetics and pharmacogenetics of aminergic pathways on FGID pathophysiology, clinical presentations, symptom severity and medical management, in an attempt of highlighting the most relevant evidence and point out issues that should be addressed in future investigations.

Sasang constitution affects the prevalence of functional dyspepsia

Background

Functional dyspepsia (FD), which is a very common disorder worldwide, is known to be caused by multiple factors including environmental and genetic factors. Sasang constitutional medicine (SCM) is a component of traditional Korean medicine that emphasizes inherited characteristics of the physical and psychological patterns of a patient. This study investigated whether the prevalence of FD differs depending on Sasang classification.

Methods

A total 517 subjects (190 males and 327 females) were recruited, and interviewed for the presence of FD using a Rome III-based questionnaire. The Sasang constitution of all subjects were diagnosed using a Sasang constitutional analytical tool (SCAT). A Chi-square test was performed to compare prevalence of DF among different Sasang constitutional types.

Results

Of the 517 subjects, 115 (22.2 %) met the diagnostic criteria for FD, and the prevalence was significantly higher in females (26.9 %) than males (14.2 %, p < 0.01). The Sasang-constitution-based prevalence among all subjects was 27.5 % for Taeumin, 23.1 % for Soumin, and 16.4 % for Soyangin (p = 0.055). When compared by sex, the prevalence of FD among Sasang types showed significantly different patterns between males and females (p < 0.05); in females with FD, Taeumin predominated (32.5 % compared with 29.5 % and 18.8 % for Soumin and Soyangin, respectively; p < 0.05), whereas males with FD displayed a higher prevalence of Soumin (17.3 % compared with 9.1 % and 11.3 % for Taeumin and Soyangin, respectively; p > 0.05).

Conclusions

This study identified significant differences in FD prevalence depending on Sasang constitution and sex. Our findings provide data to guide future research on the prevention and management of FD.

Evaluation and management of patients with symptoms after anti-reflux surgery

Over the past two decades, there has been an increase in the number of anti-reflux operations being performed. This is mostly due to the use of laparoscopic techniques, the increasing prevalence of gastroesophageal reflux disease (GERD) in the population, and the increasing unwillingness of patients to take acid suppressive medications for life. Laparoscopic fundoplication is now widely available in both academic and community hospitals, has a limited length of stay and postoperative recovery time, and is associated with excellent outcomes in carefully selected patients. Although the operation has low mortality and postoperative morbidity, it is associated with late postoperative complications, such as gas bloat syndrome, dysphagia, diarrhea, and recurrent GERD symptoms. This review summarizes the diagnostic evaluation and appropriate management of such postoperative complications. If a reoperation is needed, it should be performed by experienced foregut surgeons.

Abnormal resting brain activity in patients with functional dyspepsia is related to symptom severity

BACKGROUND & AIMS

Abnormal processing of visceral sensation at the level of the central nervous system is believed to be involved in functional dyspepsia. However, compared with studies of stimulation-related changes in brain activity, few studies have focused on resting brain activity, which also is important in pathogenesis. We mapped changes in resting brain glucometabolism of patients with functional dyspepsia, compared with healthy subjects, and attempted to correlate abnormal brain activity with symptom severity.

METHODS

We performed fluorodeoxyglucose positron emission tomography-computed tomography on 40 patients with functional dyspepsia and 20 healthy subjects who were in resting states. The symptom index of dyspepsia and the Nepean dyspepsia index were used to determine symptom severity. The positron emission tomography-computed tomography data were analyzed using statistical parametric mapping software.

RESULTS

Compared with healthy subjects, patients with functional dyspepsia had higher levels of glycometabolism in the bilateral insula, anterior cingulate cortex (ACC), middle cingulate cortex (MCC), cerebellum, thalamus, prefrontal cortex, precentral gyrus, postcentral gyrus, middle temporal gyrus, superior temporal gyrus, putamen, right parahippocampal gyrus, claustrum, and left precuneus (P < .001). The signal increase in the ACC, insula, thalamus, MCC, and cerebellum was correlated with symptom index of dyspepsia scores and Nepean dyspepsia index scores (P < .01). The glycometabolism in ACC, insula, thalamus, MCC, and cerebellum of patients with more severe functional dyspepsia was significantly higher than that of patients with less severe functional dyspepsia (P < .005).

CONCLUSIONS

In patients with functional dyspepsia, resting cerebral glycometabolism differs significantly from that of healthy subjects. The ACC, insula, thalamus, MCC, and cerebellum might be the key regions that determine the severity of symptoms.

The effect of intracerebroventricular injection of histamine in visceral nociception induced by acetic acid in rats

OBJECTIVE

This study was designed to investigate the role of brain histamine and H1 and H2 receptors in mediating the central perception of visceral pain in rats.

MATERIALS AND METHODS

In conscious rats implanted with a lateral brain ventricle cannula, the effect of intracerebroventricular (i.c.v.) injection of histamine (2.5, 10, and 40 μg), and chlorpheniramine and ranitidine at the same doses of 5, 20, and 80 μg were investigated on visceral pain. Visceral nociception induced by intraperitoneal (i.p.) injection of acetic acid (1 mL, 1%), and the number of complete abdominal wall muscle contractions accompanied with stretching of hind limbs (writhes) were counted for 1 h.

RESULTS

Histamine at doses of 10 and 40 μg and chlorpheniramine and ranitidine at the same doses of 20 and 80 μg, significantly decreased the numbers of writhes (P < 0.05). Pretreatment with chlorpheniramine and ranitidine at the same dose of 80 μg, significantly prevented histamine (40 μg)-induced antinociception (P < 0.05).

CONCLUSION

The results of this study suggest that brain histamine may be involved in modulation of visceral antinociception through both central H(1)and H(2)receptors.

Pharmacogenetics of low dose clonidine in irritable bowel syndrome

Adrenergic and serotonergic (ADR-SER) mechanisms alter gut (gastrointestinal, GI) sensorimotor functions. We aimed to determine whether candidate ADR-SER genes affect GI responses to low dose clonidine (CLO) in humans. Forty healthy and 120 irritable bowel syndrome (IBS) participants received CLO, 0.1 mg or 0.15 mg b.i.d., for 6 days. At baseline and post-CLO, we measured: gastric volume (GV); satiation volume; rectal compliance, sensation thresholds and ratings with distensions. Genetic variations tested were: alpha2A (C-1291G), alpha2C (Del 322-325), GNbeta3 (C825T) and solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) (serotonin transporter linked polymorphic region). CLO reduced volume to satiation (P = 0.002), postprandial GV (P < 0.001), sensation threshold for pain (<0.001); CLO increased rectal compliance (P = 0.024). There were significant associations between post-CLO responses and gene variations for DeltaGV (alpha2A and SLC6A4), rectal sensation of gas (alpha2A, GNbeta3), urgency (alpha2A); and pain (GNbeta3 and SLC6A4); and rectal compliance (SLC6A4). alpha2A, GNbeta3 and SLC6A4 genotypes significantly modify responses to CLO on sensory and motor GI functions in health and IBS.

Candidate genes and sensory functions in health and irritable bowel syndrome

Adrenergic and serotonergic (ADR-SER) mechanisms alter gut (GI) function; these effects are mediated through G protein transduction. Candidate genetic variations in ADR-SER were significantly associated with somatic scores in irritable bowel syndrome (IBS) and gastric emptying but not small bowel or colonic transit. Our aim was to assess whether candidate ADR-SER genes are associated with motor and sensory GI functions in IBS and subgroups on the basis of bowel dysfunction. In 122 patients with IBS and 39 healthy controls, we assessed gastrointestinal somatic symptoms and affect by validated questionnaires. We measured: gastric volume (GV), maximum tolerated volume, rectal compliance, sensation thresholds and ratings, and genetic variations including alpha2A (C-1291G), alpha2C (Del 332-325), GNbeta3 (C825T), and 5-HTTLPR. Demographics and genotype distributions were similar in the patients with IBS subgrouped on bowel function. There were significant associations between 5-HTTLPR SS genotype and absence of IBS symptoms and between 5-HTTLPR LS/SS genotype and increased rectal compliance and increased pain ratings, particularly at 12 and 24 mmHg distensions. GNbeta3 was associated only with fasting GV; we did not detect associations between alpha2A genotype and the gastrointestinal sensory or motor functions tested. We concluded that 5-HTTLPR LS/SS genotype is associated with both increased pain sensation and increased rectal compliance though the latter effect is unlikely to contribute to increased pain sensation ratings with LS/SS genotype. The data suggest the hypotheses that the endophenotype of visceral hypersensitivity in IBS may be partly related to genetic factors, and the association of GNbeta3 with fasting GV may explain, in part, the reported association of GNbeta3 with dyspepsia.

Evidence of an enhanced central 5HT response in irritable bowel syndrome and in the rat maternal separation model

Efforts to define either a biomarker for irritable bowel syndrome (IBS) or a valid animal model have proven disappointing. The aims of this study were to determine if buspirone stimulates prolactin release through the 5-hydroxytryptamine (5HT)1a receptor and whether this response is altered in patients with IBS and in the rat maternal separation model. Buspirone (30 mg) was used to stimulate prolactin release in 40 patients with IBS and in 40 healthy controls. In study 1, 10 IBS patients and 10 controls underwent pretreatment with pindolol (5HT1a antagonist) or placebo followed by buspirone. In study 2, 30 patients with IBS and 30 healthy controls had prolactin release stimulated by buspirone. Maternally separated and nonseparated rats were also treated with buspirone and prolactin monitored. Serotonin metabolites were measured together with the expression of the 5HT1a and serotonin transporter (SERT) gene. Pindolol produced a dose-dependent decrease in the buspirone prolactin response. Patients with IBS and maternally separated rats showed an exaggerated release of prolactin in response to buspirone. In the animal model, an increased turnover of 5HT was found in the brainstem together with a trend toward increased activity of the SERT gene. In conclusion altered central serotonin responses are found in both IBS and in an animal model.

Clinical trial: a randomized controlled cross-over study of flupenthixol + melitracen in functional dyspepsia

BACKGROUND

Functional dyspepsia is a prevalent condition associated with diminished quality of life (QoL) and high economic burden.

AIM

To study the efficacy of a combination of flupenthixol and melitracen (F + M) with anxiolytic and antidepressant properties in functional dyspepsia using a randomized controlled cross-over design.

METHODS

Patients met the Rome III criteria for functional dyspepsia and a validated questionnaire was used to exclude those with anxiety or depression. Moreover, patients had to have failed a trial of acid-suppressive therapy and Helicobacter pylori eradication when positive. End points included subjective global symptom relief and QoL assessed by the Nepean Dyspepsia Index (NDI).

RESULTS

Twenty-five patients (14 females, 11 males; mean age = 34.3 +/- 9.9 years) were enrolled and 24 completed the 8-week study. There was a significant improvement in subjective global symptom relief with F + M vs. placebo (ITT: 73.9% vs. 26.1%, P = 0.001) and a significant drop in the NDI score vs. placebo (ITT: -9.0 +/- 11.9 vs. -2.4 +/- 8.9, P = 0.03). No difference was noted whether the initial treatment was F + M or placebo. No significant side effects were noted.

CONCLUSIONS

A combination of F and M is safe and effective in the short-term treatment of functional dyspepsia. F + M is associated with significant improvement in QoL independent of the presence of anxiety or depression.

Visceral sensitivity and expression of 5-hydroxytryptamine and c-fos in the spinal dorsal horn in a rat model with irritable bowel syndrome

AIM: To study the visceral sensitivity by rectal balloon distension and expression of 5-hydroxy-tryptamine (5-HT) and c-fos in the spinal dorsal horn of a rat model with constipation-predominant irritable bowel syndrome (C-IBS).

METHODS: The rat model was established by intragastric injection with ice-cold water (0-4℃). The perception thresholds and the number of abdominal withdrawal reflexes (AWRs) were recorded during rectal balloon distention in order to evaluate visceral sensitivity in the model group (A, n = 10) and control group (B, n = 10). Expression of 5-HT and c-fos in the spinal dorsal horn was shown by immunohistochemical staining, and analyzed semi-quantitatively by computerized color image analyzer using immunoreactive areas and optical density (OD). The statistical difference of the OD and immunoreactive areas between the two groups was examined by t test.

RESULTS: The perception threshold in group A was slightly higher than that in group B during rectal balloon distention, but there was no significant difference (0.59 ± 0.09 vs 0.57 ± 0.13, P > 0.05). The number of AWRs to the lower balloon content (1.0 mL) was much lower in group A than in group B (10.3 ± 3.3 vs 18.3 ± 5.5, P < 0.05), although no difference was found to the higher balloon content (1.5 and 2.0 mL). Immunoreactive area and OD of 5-HT- and c-fos-positive neurons and fibers in group A were significantly higher than those in group B (5-HT immunoreactive area, 146.5 ± 15.1 vs 109.3 ± 18.5; 5-HT OD, 45826 ± 2563.2 vs 29358 ± 8965.5; c-fos immunoreactive area, 125.4 ± 23.3 vs 88.7 ± 23.2; c-fos OD, 46258 ± 4642 vs 33238 ± 4587; all P < 0.05).

CONCLUSION: The model of C-IBS has a decreased visceral sensitivity to rectal balloon distention. The increased expression of 5-HT and c-fos in the spinal dorsal horn is probably involved in the process.

Recent insights into digestive motility in functional dyspepsia

Functional gastrointestinal disorders, such as functional dyspepsia (FD) and irritable bowel syndrome, are common pathologies of the gut. FD is a clinical syndrome defined as chronic or recurrent pain or discomfort of unknown origin in the upper abdomen. The pathophysiological mechanisms responsible for FD have not been fully elucidated, but new ideas regarding its pathophysiology and the significance of the pathophysiology with respect to the symptom pattern of FD have emerged. In particular, there is growing interest in alterations in gastric motility, such as accommodation to a meal or gastric emptying, and visceral sensation in FD. The mechanisms underlying impaired gastroduodenal motor function are unclear, but possible factors include abnormal neurohormonal function, autonomic dysfunction, visceral hypersensitivity to acid or mechanical distention, Helicobacter pylori infection, acute gastrointestinal infection, psychosocial comorbidity, and stress. Although the optimum treatment for FD is not yet clearly established, acid-suppressive drugs, prokinetic agents, eradication of H. pylori, and antidepressants have been widely used in the management of patients with FD. The therapeutic efficacy of prokinetics such as itopride hydrochloride and mosapride citrate in the treatment of FD is supported by the results of relatively large and well-controlled studies. In addition, recent research has yielded new therapeutic agents and modalities for dysmotility in FD, including agonists/antagonists of various sensorimotor receptors, activation of the nitrergic pathway, kampo medicine, acupuncture, and gastric electric stimulation. This review discusses recent research on the pathophysiology of and treatment options for FD, with special attention given to digestive dysmotility.

Reassessment of functional dyspepsia: A topic review

Dyspepsia itself is not a diagnosis but stands for a constellation of symptoms referable to the upper gastrointestinal tract. It consists of a variable combination of symptoms including abdominal pain or discomfort, postprandial fullness, abdominal bloating, early satiety, nausea, vomiting, heartburn and acid regurgitation. Patients with heartburn and acid regurgitation invariably have gastroesophageal reflux disease and should be distinguished from those with dyspepsia. There is a substantial group of patients who do not have a definite structural or biochemical cause for their symptoms and are considered to be suffering from functional dyspepsia (FD). Gastrointestinal motor abnormalities, altered visceral sensation, dysfunctional central nervous system-enteral nervous system (CNS-ENS) integration and psychosocial factors have all being identified as important pathophysiological correlates. It can be considered as a biopsychosocial disorder with dysregulation of the brain-gut axis being central in origin of disease. FD can be categorized into different subgroups based on the predominant single symptom identified by the patient. This subgroup classification can assist us in deciding the appropriate symptomatic treatment for the patient.