Effects of motilin on human interdigestive gastrointestinal and gallbladder motility, and involvement of 5HT3 receptors

Hesperidin facilitating gastrointestinal motility by "Gut-brain axis" and "SCF/C-Kit signaling pathways"

Hesperidin shows promising results as a potential feed additive for enhancing gastrointestinal motility in animals. Gastrointestinal function plays a pivotal role in animal growth and the digestibility of dietary nutrients, with gastrointestinal motor function serving as a crucial component. However, limited research has been conducted on the application of hesperidin as a feed additive to promote gastrointestinal motility. The present study aims to assess the efficacy of Hesperidin as a feed additive in promoting gastrointestinal motility and elucidating its underlying mechanism. A total of 200 newly hatched (1-day-old) broilers with similar body weight were randomly allocated into 4 groups as follows: the control group receiving only the basal diet, and the other 3 groups supplemented with 50, 100, and 150 mg of hesperidin per kg of the basal diet, respectively. Each group consisted of 5 replicates with ten broilers per replicate, and the feeding trial lasted for a duration of 21 d. At 21 d of age, a 5% w/v Evans Blue solution in distilled water was utilized to measure intestinal transit rates (ITR). Gastric emptying (GE) was evaluated by administering a phenol red solution at a concentration of 0.05% w/v (1 mL/broiler). Fifteen broilers from each group were euthanized and immediately dissected to obtain gizzard, hypothalamus, duodenum, and jugular blood samples. Jugular blood samples were collected for brain-gut peptide content analysis, while gizzard, hypothalamus, and duodenum samples were used for immunohistochemical analysis. Real-time qPCR was performed on gizzard samples. The results demonstrated a significant improvement in the GE and ITR of broilers in all treatment groups compared to the control group (P < 0.05), particularly in the 100mg/Kg and 150mg/Kg hesperidin group. Incorporation of hesperidin into the broilers' diet significantly enhances serum levels of ghrelin, encompassing serotonin (5-HT), motilin (MTL), cholecystokinin (CCK), and Stem Cell Factor (SCF) as well as substance P (SP) in the gizzard and duodenal tissues while reducing vasoactive intestinal peptide (VIP) levels (P < 0.05). The group administered a dosage of 150mg/Kg exhibited the most pronounced effect.Immunohistochemistry analysis revealed that hesperidin supplementation up-regulated SP protein content and down-regulated VIP protein content in the hypothalamus, gizzard, and duodenum of broilers (P < 0.05), with the most pronounced effect illustrated in the 150mg/Kg hesperidin group. Furthermore, addition of hesperidin to broiler feed resulted in a significant up-regulation of protein expression and gene expression related to SCF and The protein expression of Receptor tyrosine kinase (C-Kit) was significantly upregulated in the 150mg/Kg group, while the gene expression of C-Kit was significantly upregulated in the 50 mg/Kg group (P < 0.05). In conclusion, hesperidin exhibits promising potential as a feed additive for broilers, as its dietary supplementation of hesperidin improves gastrointestinal motility through modulation of both "gut-brain axis" signaling pathways and "SCF/C-Kit signaling pathways" within broiler chicken's digestive system. Notably, basal diet supplemented with 150mg/Kg hesperidin demonstrates superior efficacy.

The influence of herbal medicine on serum motilin and its effect on human and animal model: a systematic review

Introduction: Motilin (MLN) is a gastrointestinal (GI) hormone produced in the upper small intestine. Its most well understood function is to participate in Phase III of the migrating myoelectric complex component of GI motility. Changes in MLN availability are associated with GI diseases such as gastroesophageal reflux disease and functional dyspepsia. Furthermore, herbal medicines have been used for several years to treat various GI disorders. We systematically reviewed clinical and animal studies on how herbal medicine affects the modulation of MLN and subsequently brings the therapeutic effects mainly focused on GI function. Methods: We searched the PubMed, Embase, Cochrane, and Web of Science databases to collect all articles published until 30 July 2023, that reported the measurement of plasma MLN levels in human randomized controlled trials and in vivo herbal medicine studies. The collected characteristics of the articles included the name and ingredients of the herbal medicine, physiological and symptomatic changes after administering the herbal medicine, changes in plasma MLN levels, key findings, and mechanisms of action. The frequency patterns (FPs) of botanical drug use and their correlations were investigated using an FP growth algorithm. Results: Nine clinical studies with 1,308 participants and 20 animal studies were included in the final analyses. Herbal medicines in clinical studies have shown therapeutic effects in association with increased levels of MLN, including GI motility regulation and symptom improvement. Herbal medicines have also shown anti-stress, anti-tumor, and anti-inflammatory effects in vivo. Various biochemical markers may correlate with MLN levels. Markers may have a positive correlation with plasma MLN levels included ghrelin, acetylcholine, and secretin, whereas a negative correlation included triglycerides and prostaglandin E2. Markers, such as gastrin and somatostatin, did not show any correlation with plasma MLN levels. Based on the FP growth algorithm, Glycyrrhiza uralensis and Paeonia japonica were the most frequently used species. Conclusion: Herbal medicine may have therapeutic effects mainly on GI symptoms with involvement of MLN regulation and may be considered as an alternative option for the treatment of GI diseases. Further studies with more solid evidence are needed to confirm the efficacy and mechanisms of action of herbal medicines. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=443244, identifier CRD42023443244.

Physiological functions and potential clinical applications of motilin

Motilin is a gastrointestinal hormone secreted by the duodenum. This peptide regulates a characteristic gastrointestinal contraction pattern, called the migrating motor complex, during the fasting state. Motilin also affects the pressure of the lower esophageal sphincter, gastric motility and gastric accommodation in the gastrointestinal tract. Furthermore, motilin induces bile discharge into the duodenum by promoting gallbladder contraction, pepsin secretion in the stomach, pancreatic juice and insulin secretion from the pancreas. In recent years, it has been shown that motilin is associated with appetite, and clinical applications are expected for diseases affected by food intake, e.g. obesity, by regulating motilin levels. Gastric acid and bile are the two major physiological regulators for motilin release. Caloric foods have varying effects on motilin levels, depending on their composition. Among non-caloric foods, bitter substances reduce motilin levels and are therefore expected to have an appetite-suppressing effect. Various motilin receptor agonists and antagonists have been developed but have yet to reach clinical use.

Analysis of Risk Factors and Establishment of a Prediction Model for Endoscopic Primary Bile Reflux: A Single-Center Retrospective Study

Background: Endoscopic primary bile reflux is one of the main diagnostic criteria for bile reflux gastritis (BRG). Presently, the risk factors and prediction models of endoscopic primary bile reflux (EPBR) in gastropathy patients who cannot or will not undergo endoscopy due to contraindications are not clear. Thus, this study aimed to evaluate the risk factors of EPBR and to establish and verify a prediction model.

Methods: A series of 844 patients (564 subjects with EPBR and 280 control subjects) were retrospectively selected for this study and divided into a training set (n = 591) and a validation set (n = 253) according to the usual ratio of 70:30% for the subsequent internal validation of the logistic regression model for EPBR. Fifteen parameters that might affect the occurrence of EPBR were collected. Subsequently, univariate and stepwise logistic regression analyses were introduced to reveal the risk factors and the multivariate prediction model. An R package was dedicated to the corresponding internal validation of the EPBR model.

Results: The univariate analysis showed that gender, age, smoking, Helicobacter pylori (H. pylori) infection status, metabolic syndrome (MS), non-steroidal anti-inflammatory drugs (NSAIDs) use history, and previous medical histories of chronic liver diseases, cholelithiasis, and erosive gastritis were statistically significant between the two groups (P < 0.05). Multivariate regression described that being a male [OR (95%confidence interval (CI)) = 2.29 (1.50–3.50), P < 0.001], age≥45 years old [OR (95% CI) = 4.24 (2.59–6.96), P < 0.001], H. pylori infection status [OR (95% CI) = 2.34 (1.37–4.01), P = 0.002], MS [OR (95% CI) = 3.14 (1.77–5.54), P < 0.001], NSAIDs use history [OR (95% CI) = 1.87 (1.03–3.40), P = 0.04], cholelithiasis history [OR (95% CI) = 3.95 (2.18–7.18), P < 0.001] and erosive gastritis history [OR (95% CI) = 6.77 (3.73–12.29), P < 0.001] were the risk factors for the occurrence of EPBR. Based on the results of these risk factors, an EPBR prediction model with an adequate calibration and excellent discrimination was established [area under the curve (AUC): 0.839, 95% CI = 0.806–0.872].

Conclusions: Being a male, age ≥ 45 years old, H. pylori infection, histories of MS, NSAIDs use, cholelithiasis, and erosive gastritis appear to be the risk factors for EPBR, and our favorable prediction model might be an option for the prediction of EPBR.

International Union of Basic and Clinical Pharmacology. CX. Classification of Receptors for 5-hydroxytryptamine; Pharmacology and Function

5-HT receptors expressed throughout the human body are targets for established therapeutics and various drugs in development. Their diversity of structure and function reflects the important role 5-HT receptors play in physiologic and pathophysiological processes. The present review offers a framework for the official receptor nomenclature and a detailed understanding of each of the 14 5-HT receptor subtypes, their roles in the systems of the body, and, where appropriate, the (potential) utility of therapeutics targeting these receptors. SIGNIFICANCE STATEMENT: This review provides a comprehensive account of the classification and function of 5-hydroxytryptamine receptors, including how they are targeted for therapeutic benefit.

Pathophysiology, Aetiology and Treatment of Gastroparesis

Gastroparesis is characterized by delayed gastric emptying, with symptoms such as nausea, vomiting and abdominal pain, in the absence of mechanical obstruction. In most cases, it is idiopathic although diabetes mellitus is another leading cause. The physiology of gastric emptying is a complex process which is influenced by various inputs including the central nervous system, enteric nervous system and gut hormones. Developments in our understanding of gastroparesis have now demonstrated dysfunction in these systems, thus disrupting normal gastric emptying. Once mechanical obstruction is excluded, gastric scintigraphy remains the gold standard for diagnosis although wireless motility capsule and breath testing are alternative methods for diagnosis. Treatment for gastroparesis is challenging, and widely available therapies are often limited either by their poor evidence for efficacy or concerns over their long-term safety profile. Novel prokinetic agents have shown initial promise in clinical trials, and new endoscopic techniques such as gastric per-oral endoscopic myotomy are emerging. These new treatment modalities may provide an option in refractory gastroparesis with the adage of reduced morbidity compared to surgical treatments.

Motilin: a panoply of communications between the gut, brain, and pancreas

Introduction: Motilin was first alluded to nearly a century ago. But it remains a rather abstruse peptide, in the shadow of its younger but more lucid 'cousin' ghrelin.Areas covered: The review aimed to bring to the fore multifarious aspects of motilin research with a view to aiding prioritization of future studies on this gastrointestinal peptide.Expert opinion: Growing evidence indicates that rodents (mice, rats, guinea pigs) do not have functional motilin system and, hence, studies in these species are likely to have a minimal translational impact. Both the active peptide and motilin receptor were initially localized to the upper gastrointestinal tract only but more recently - also to the brain (in both humans and other mammals with functional motilin system). Motilin is now indisputably implicated in interdigestive contractile activity of the gastrointestinal tract (in particular, gastric phase III of the migrating motor complex). Beyond this role, evidence is building that there is a cross-talk between motilin system and the brain-pancreas axis, suggesting that motilin exerts not only contractile but also orexigenic and insulin secretagogue actions.

Research on mechanism of charred hawthorn on digestive through modulating "brain-gut" axis and gut flora

ETHNOPHARMACOLOGICAL RELEVANCE

Hawthorn is a traditional Chinese medicine for high-calorie-diet-induced dyspepsia (HC-DID) for thousands of years old. Based on traditional Chinese medicine (TCM) theory and clinical and non-clinical trials, its stir-frying processed product, charred hawthorn, possesses better effect. At present, most research mainly focuses on chemical constituents of hawthorn before and after stir-frying process, but there is no relevant action-mechanism study about fragrant odor promoting HC-DID during the stir-frying process of the hawthorn.

AIM OF THE STUDY

The purpose of the present study is to research on mechanism of hawthorn decoction coupled with odor of charred hawthorn on digestive in rats with HC-DID.

MATERIALS AND METHODS

The SPF Kunming (KM) mice and Sprague Dawley (SD) rats were randomly divided into 7 groups: control group, model group, cisapride group, hawthorn group (HT), charred hawthorn group (CHT), odor of charred hawthorn (OCHT), CHT + OCHT group. The rats were modeled as HC-DID, whose treatment by intragastric administration and odor administration. Obvious symptoms of HC-DID were observed. Gastrointestinal motility were detected. Histopathology was performed in hypothalamus and gastrointestinal tract. Related brain-gut peptides were assayed in serum, hypothalamus and gastrointestinal tract. Illumina Miseq platform was used for 16S rDNA high-throughput sequencing to detect the intestinal flora structure of the caecum of rats.

RESULTS

Traditional Chinese medicine decoction of hawthorn (HT and CHT) regulated the body weight, food intake, gastrointestinal motility and abnormal secretion of brain-gut peptides in rats with HC-DID, and the odor of charred hawthorn also had good curative effect for it. Moreover, the intestinal dysbiosis was induced by high-calorie diet in rats with dyspepsia, and hawthorn decoction could ease this trend.

CONCLUSION

The above study showed that hawthorn decoction coupled with the odor of charred hawthorn effectively alleviate HC-DID in rats by regulating the "Brain-Gut" axis and gut flora. Odor treatment of hawthorn could be a potential therapeutic approach for HC-DID.

Motilin: from gastric motility stimulation to hunger signalling

After the discovery of motilin in 1972, motilin and the motilin receptor were studied intensely for their role in the control of gastrointestinal motility and as targets for treating hypomotility disorders. The genetic revolution - with the use of knockout models - sparked novel insights into the role of multiple peptides but contributed to a decline in interest in motilin, as this peptide and its receptor exist only as pseudogenes in rodents. The past 5 years have seen a major surge in interest in motilin, as a series of studies have shown its relevance in the control of hunger and regulation of food intake in humans in both health and disease. Luminal stimuli, such as bitter tastants, have been identified as modulators of motilin release, with effects on hunger and food intake. The current state of knowledge and potential implications for therapy are summarized in this Review.

Efficacy of Gum Chewing on Bowel Movement After Open Colectomy for Left-Sided Colorectal Cancer: A Randomized Clinical Trial

BACKGROUND

Prolonged intestinal paralysis can be a problem after gastrointestinal surgery. Several systematic reviews and meta-analyses have suggested the efficacy of gum chewing for the prevention of postoperative ileus.

OBJECTIVE

The purpose of this study was to examine the efficacy of gum chewing for the recovery of bowel function after surgery for left-sided colorectal cancer and to determine the physiological mechanism underlying the effect of gum chewing on bowel function.

DESIGN

This was a single-center, placebo-controlled, parallel-group, prospective randomized trial.

SETTINGS

The study was conducted at a general hospital in Japan.

PATIENTS

Forty-eight patients with left-sided colorectal cancer were included.

INTERVENTIONS

The patients were randomly assigned to a gum group (N = 25) and a control group (N = 23). Four patients in the gum group and 1 in the control group were subsequently excluded because of difficulties in continuing the trial, resulting in the analysis of 21 and 22 patients in the respective groups. Patients in the gum group chewed commercial gum 3 times a day for ≥5 minutes each time from postoperative day 1 to the first day of food intake.

MAIN OUTCOME MEASURES

The time to first flatus and first bowel movement after the operation were recorded, and the colonic transit time was measured. Gut hormones (gastrin, des-acyl ghrelin, motilin, and serotonin) were measured preoperatively, perioperatively, and on postoperative days 1, 3, 5, 7, and 10.

RESULTS

Gum chewing did not significantly shorten the time to the first flatus (53 ± 2 vs. 49 ± 26 hours; p = 0.481; gum vs. control group), time to first bowel movement (94 ± 44 vs. 109 ± 34 hours; p = 0.234), or the colonic transit time (88 ± 28 vs. 88 ± 21 hours; p = 0.968). However, gum chewing significantly increased the serum levels of des-acyl ghrelin and gastrin.

LIMITATIONS

The main limitation was a greater rate of complications than anticipated, which limited the significance of the findings.

CONCLUSIONS

Gum chewing changed the serum levels of des-acyl ghrelin and gastrin, but we were unable to demonstrate an effect on the recovery of bowel function.

Variants in motilin, somatostatin and their receptor genes and risk of biliary tract cancers and stones in Shanghai, China

Altered motility of the gallbladder can result in gallstone and cholecystitis, which are important risk factors for biliary tract cancer. Motilin (MLN) and somatostatin (SST) are known important modulators of gallbladder motility. To determine whether genetic variants in motilin, somatostatin, and their receptor genes are associated with the risk of biliary tract cancers and stones, nine tag-SNPs were determined in 439 biliary tract cancer cases (253 gallbladder, 133 extrahepatic bile duct and 53 ampulla of Vater cancer cases), 429 biliary stone cases, and 447 population controls in a population-based case–control study in Shanghai, China. We found that subjects with the MLNR rs9568169 AA genotype and SSTR5 rs169068 CC genotype were significantly associated with risk of extrahepatic bile duct cancer (OR = 0.49, 95% CI: 0.27–0.89; OR = 2.40, 95% CI: 1.13–5.13) compared to the major genotypes. MLN rs2281820 CT and rs3793079 AT genotypes had significantly increased risks of gallstones (OR = 1.52, 95% CI: 1.06–2.18; OR = 1.64, 95% CI: 1.20–2.25) compared to TT genotypes. Besides, haplotype analysis showed that MLN T-T-T haplotype (rs2281820–rs3793079–rs2281819) had a non-significantly elevated risk of gallstone (OR = 1.30, 95% CI: 0.91–1.86) compared with C-A-A haplotype. To the best of our knowledge, this is the first study to report an association between genetic polymorphisms in MLN, MLNR and their receptor genes and risk of biliary tract cancers and stones.

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We conduct a population-based case–control study of biliary tract diseases in China.

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We examine nine TagSNPs in gallbladder motility genes in this study.

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MLNR rs9568169 and SSTR5 rs169068 are related to extrahepatic bile duct cancer risk.

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MLN rs2281820 and rs3793079 are associated with gallstone risk.

Food intake and interdigestive gastrointestinal motility in ghrelin receptor mutant rats

BACKGROUND

Ghrelin is the endogenous ligand for the growth hormone secretagogue receptor (GHSR). Ghrelin regulates feeding activity and interdigestive contractions of the stomach in rodents. To investigate the role of endogenous ghrelin in the digestive system, we have developed GHSR-mutant rats, named FHH-Ghsr(m1Mcwi), using the Fawn-Hooded Hypertensive (FHH) parental strain.

METHODS

N-ethyl-N-nitrosourea (ENU) was used as a mutagen. Genomic DNA prepared from a tail clip was analyzed using the targeting induced local lesions in genomes (TILLING) approach. The non-synonymous mutation in position 343 (NM_032075) led to the generation of a premature stop codon, causing deletion of the last 22 amino acids at the C-terminal of ghrelin receptor protein. Spontaneous and ghrelin-stimulated food intake was measured in wild-type (WT) FHH and FHH-Ghsr(m1Mcwi) rats. For interdigestive motility recording, two strain gauge transducers were sutured on the antrum and duodenum. Spontaneous gastroduodenal contractions were recorded in freely moving conscious rats.

RESULTS

Ghrelin (40 μg/kg) failed to stimulate food intake in the mutant rats, while spontaneous food intake was not significantly different between the WT rats and FHH-Ghsr(m1Mcwi) rats. Phase III-like contractions were observed in stomach and duodenum both in the WT and FHH-Ghsr(m1Mcwi) rats. In the WT rats, ghrelin (12 μg/kg) administration enhanced spontaneous phase III-like contractions, and a GHSR antagonist, (D-lys3)GHRP-6 (0.28 mg/kg), abolished the spontaneous phase III-like contractions. In FHH-Ghsr(m1Mcwi) rats, ghrelin and (D-lys3)GHRP-6 did not affect phase III-like contractions.

CONCLUSIONS

It is suggested that the intact GHSR structure is essential for the ghrelin-dependent regulation of interdigestive motility and feeding behavior. Even in FHH-Ghsr(m1Mcwi) rats, spontaneous gastric phase III-like contractions were still observed, suggesting the development of a compensatory mechanism to maintain these contractions.

Mechanisms underlying the roles of nervous and humoral factors in the pathogenesis of gallstones

Gallstone disease is a common disorder with an incidence rate of about 10%. Recent research has revealed that nervous and humoral factors are involved in the pathogenesis of gallstone disease. This article focuses on the mechanisms underlying the roles of parasympathetic nerve, sympathetic nerve, non-adrenergic non-cholinergic nerve, cholecystokinin, gastrin, bombesin, gastrin-releasing peptide, motilin, vasoactive intestinal polypeptide, somatostatin, pancreatic polypeptide, substance P, secretin, neurotensin, opioid peptide, nitric oxide, estrogen, thyroxine, and leptin in the pathogenesis of gallstones.

Effects of a 5-HT(3) antagonist, ondansetron, on fasting and postprandial small bowel water content assessed by magnetic resonance imaging

BACKGROUND

5-HT(3) antagonists have been shown to be effective in relieving the symptoms of irritable bowel syndrome with diarrhoea (IBS-D). Using a recently validated magnetic resonance imaging (MRI) method, we have demonstrated reduced fasting small bowel water content (SBWC) in IBS-D associated with accelerated small bowel transit. We hypothesized that slowing of transit with ondansetron would lead to an increase in SBWC by inhibiting fasting motility.

AIM

To assess the effects of ondansetron compared with placebo in healthy volunteers on SBWC and motility in two different groups of subjects, one studied using MRI and another using manometry.

METHODS

Healthy volunteers were given either a placebo or ondansetron on the day prior to and on the study day. Sixteen volunteers underwent baseline fasting and postprandial MRI scans for 270 min. In a second study, a separate group of n = 18 volunteers were intubated and overnight migrating motor complex (MMC) recorded. Baseline MRI scans were carried out after the tube was removed.

RESULTS

Fasting SBWC was markedly increased by ondansetron (P < 0.0007). Ondansetron reduced the overall antroduodenal Motility Index (P < 0.04). The subjects who were intubated had significantly lower fasting SBWC (P < 0.0002) compared with the group of subjects who were not intubated.

CONCLUSIONS

The 5-HT(3) receptor antagonism increased fasting small bowel water. This was associated with reduced fasting antroduodenal Motility Index which may explain the clinical benefit of such drugs.

Association between plasma ghrelin and motilin levels during MMC cycle in conscious dogs

BACKGROUND

Migrating motor complex (MMC) is well characterized by the appearance of gastrointestinal contractions in the interdigestive state. Gastric phase III contractions of MMC are regulated by motilin, but not ghrelin, in dogs. Ghrelin regulates feeding activity in dogs and rodents. It remains unclear how motilin and ghrelin interact during the MMC cycle in dogs.

METHODS

Four strain gauge transducers were implanted on stomach and intestine in 6 female dogs. To investigate the correlation between ghrelin and motilin, plasma motilin and acyl ghrelin (active type) levels were measured by radioimmunoassay (RIA) during MMC cycle.

RESULTS

The peak of plasma motilin levels was always observed at the period of gastric phase III contractions. The peak of ghrelin levels were followed 20-25 min after the peak of plasma motilin levels in 13 cases of 18 observations (72.2%). These were frequently observed at the early stage of gastric phase I contractions. In 3 of 16 observations (18.8%), the ghrelin peak was not associated with the motilin peaks. Immediately after the feeding, the interdigestive GI motor pattern was changed to the postprandial pattern. No significant increases of the plasma motilin levels and ghrelin levels were observed after the feeding.

CONCLUSION

This is the first demonstration showing the correlation between ghrelin and motilin levels during gastric MMC cycle in conscious dogs. As it is rather difficult to evaluate the hunger score in dogs, it remains unclear whether increased ghrelin levels after finishing gastric phase III contractions may mediate hunger sensation in dogs.

The physiology of gastric emptying

The gastric emptying rate is a carefully regulated process consisting of different mathematically defined phases. The gastric metabolic load, as well as neural regulatory mechanisms and hormonal influences, cooperate in order to achieve a well-balanced emptying of contents from the stomach into the duodenum for absorption in the small intestine. This finely tuned regulation is primarily regulated by the release of gastrointestinal peptide hormones which serve to counteract the emptying process in the fed state and to stimulate sweeping contractions in the fasted state, most likely in order to prepare the stomach for another meal. We have found that the two peptide hormones ghrelin and glucagon-like peptide- I (GLP- I) have a great impact on the regulation of gastric emptying: ghrelin is a most potent stimulator of gastric contractions and emptying, and GLP- I profoundly inhibits this emptying process. These data suggest possibilities for governing the rate of gastric emptying as a natural step in achieving metabolic balance and control.

Duodenal interdigestive migrating motor complex in patients 5 years or more after pylorus-preserving gastrectomy for early gastric cancer

BACKGROUND

We investigated the relationship between interdigestive migrating motor complex, phase III (IMMC-pIII) and postoperative quality of life (QOL) in pylorus-preserving gastrectomy (PPG) patients.

MATERIALS AND METHODS

A total of 40 patients (26 men and 14 women; average age 59.4 years) 5 to 7.5 years after PPG for early gastric cancer (Billroth I) (average 6 years and 3 months) were divided into two groups according to the occurrence of IMMC-pIII from the duodenum, and their postoperative quality of life (QOL) was compared.

RESULTS

As for appetite, "No change compared with before operation" was significantly more frequent in the IMMC-pIII positive group compared with the negative group (P=0.0002). Food consumption per meal compared with normal; "80% or more" was significantly more frequent in the IMMC-pIII positive group than the negative group (P=0.0002). Body weight loss during 5 years after surgery; "6 kg or more" was significantly more frequent in the IMMC-pIII negative group than the positive group (P=0.0002). Early dumping symptoms did not occur in any patients of either group. Reflux esophagitis and nausea; no patients in the IMMC-pIII positive group experienced these symptoms, which was significantly different from the negative group (P=0.0018). Abdominal pain occurred but was significantly less frequent in the IMMC-pIII positive group than in the negative group (P=0.0023). Epigastric fullness occurred but was less frequent in the IMMC-pIII positive group compared with the negative group (P<0.0001). Gastric stasis of the remnant stomach was significantly more frequent in the IMMC-pIII negative group than in the positive group (P<0.0001). Gholelithiasis was significantly more frequent in the IMMC-pIII negative group than in the positive group (P=0.0119).

CONCLUSIONS

These results showed more satisfactory QOL in the IMMC-PIII positive group than in the negative group.

Intragastric acidification inhibits motilin-induced phase III activity in humans

In a randomized, placebo-controlled crossover design we studied the effect of gastric acidification on motilin-induced interdigestive antropyloroduodenal motility. Ten healthy volunteers participated in the study consisting of four experiments. Each experiment started after a spontaneous occurring phase III and consisted of intragastric infusion of either saline or acid (0.08 mol L(-1) HCl) for 90 min and intravenous infusion of either saline or motilin (4 pmol kg(-1) min(-1)) for 30 min. Antropyloroduodenal motility and pH were recorded continuously for 240 min. Reoccurrence of phase III was significantly (P < 0.05) earlier during intragastric saline-intravenous motilin infusion compared with control (intragastric saline-intravenous saline), 52 min (range 25-79) and 113 min (84-141) respectively. This effect was completely abolished during intragastric acid-intravenous motilin infusion, 112 min (82-142). The percentage of phase III of antral origin was significantly (P < 0.05) higher during intragastric saline-intravenous motilin infusion (90%) compared with control (30%). The mean area under the contraction (AUC) for phase II was significantly (P < 0.05) lower during intragastric saline-intravenous motilin infusion and intragastric acid-intravenous saline infusion compared with control. It is concluded that in humans intragastric acidification inhibits the effect of motilin on antroduodenal motility, decreases the AUC of antral phase II contractions and delays the occurrence of phase III of the migrating motor complex.

Fundamentals of neurogastroenterology: basic science

The focus of neurogastroenterology in Rome II was the enteric nervous system (ENS). To avoid duplication with Rome II, only advances in ENS neurobiology after Rome II are reviewed together with stronger emphasis on interactions of the brain, spinal cord, and the gut in terms of relevance for abdominal pain and disordered gastrointestinal function. A committee with expertise in selective aspects of neurogastroenterology was invited to evaluate the literature and provide a consensus overview of the Fundamentals of Neurogastroenterology textbook as they relate to functional gastrointestinal disorders (FGIDs). This review is an abbreviated version of a fuller account that appears in the forthcoming book, Rome III. This report reviews current basic science understanding of visceral sensation and its modulation by inflammation and stress and advances in the neurophysiology of the ENS. Many of the concepts are derived from animal studies in which the physiologic mechanisms underlying visceral sensitivity and neural control of motility, secretion, and blood flow are examined. Impact of inflammation and stress in experimental models relative to FGIDs is reviewed as is human brain imaging, which provides a means for translating basic science to understanding FGID symptoms. Investigative evidence and emerging concepts implicate dysfunction in the nervous system as a significant factor underlying patient symptoms in FGIDs. Continued focus on neurogastroenterologic factors that underlie the development of symptoms will lead to mechanistic understanding that is expected to directly benefit the large contingent of patients and care-givers who deal with FGIDs.

Effect of bile acid enterohepatic circulation on interdigestive migrating motor complex

AIM: To investigate the effects of enterohepatic circulation of bile acid on interdigestive migrating motor complex (MMC).

METHODS: The dog models of extracorporeal circulation of bile acid were established firstly (n = 12). Then the records of MMC were observed with bile flow intact, during total external biliary diversion and after re-infusion of the bile into the dogs duodenum respectively. At the same time, the concentration of plasma motilin (MTL) was measured under different conditions.

RESULTS: The interdigestive MMC with bile flow intact included 3 phases. The concentration of plasma MTL cycled with MMC. The level of MTL in phase Ⅲ was much higher than that in phaseⅠ(433.8 ± 46.3 ng/L vs 112.6 ± 21.7 ng/L, P = 0.000 < 0.01). During total external biliary diversion, phase Ⅲ was not obvious. Compared with the normal period of MMC, the one during total external biliary divevsion was much longer (110.2 ± 13.6 min vs 99.1 ± 14.4 min, P = 0.001 < 0.01); the duration of phaseⅠwas shorter (31.0 ± 6.6 min vs 53.2 ± 9.2 min, P = 0.002 < 0.01) and that of phase Ⅱ was longer (79.2 ± 11.8 min vs 41.3 ± 9.9 min, P = 0.001 < 0.01). The dynamic index of last 30 min of phase Ⅱwas lower than that of normal (41.3 ± 6.8 mV/s vs 69.1 ± 9.2 mV/s, P = 0.001 < 0.01). At the same time, the concentrations of plasma MTL did not show significant differences with the changing of MMC. Phase Ⅲ was also not obvious after re-infusion of the bile. However, compared with pre-infusion, the characteristics of MMC changed and were more similar to normal MMC.

CONCLUSION: Enterohepatic circulation of bile acid plays an important role in the maintenance of interdigestive MMC. MTL is an important factor in the initiation of phase Ⅲ of MMC.

Effect of portal azygous disconnection on gallbladder motor function

AIM: To investigate and clarify the effect of vagus on gallbladder motility through a comparative study.

METHODS: Twenty-three hepatocirrhosis patients with portal hypertension were included in this study. In Hassab operation group, the anterior and posterior trunk of vagus were surgically excised (H, n = 18); In vena coronaria ventriculi embolization group, the vena coronaria ventriculi bole was ligated and injected TH adhesive (8 mL) after splenectomy (VCE, n = 5). Before operation and 10 d after operation, ^99mTc-labeled diethyl acetyl acid anilide iminodiacetic acid (^99mTc-EHIDA, 185 MBq) was administered intravenously to the patients, and then scintigraphic method was used to assess the motor function of gallbladder. The index including radiocounting 30 min after injected ^99mTc-EHIDA (GBRC 30min), emptying fraction (GBEF), emptying period (GBEP), emptying rate (GBER), latent period (GBLP), latent period radiocounting increment (GBLI) and latent period radiocounting increment rate (GBLR) were analyzed.

RESULTS: GBRC 30 min in H group was significantly lower after operation than that before operation (74.8 ± 66.9 vs 155.7 ± 72.9,P < 0.05); GBLP was very short in pre-operation, and GBLP prolonged significantly after operation (13.36 ± 5.92 vs 2.24 ± 1.48, P < 0.01); the gallbladder radiocounting increased gradually during GBLP; the GBLI and GBLP level were very low before operation, but the GBLI and GBLP increased significantly after operation (79.5 ± 56.3 vs 9.2 ± 11.7, 113.4 ± 49.5 vs 7.6 ± 10.8, P < 0.01); GBEP shortened significantly after operation (18.5 ± 6.3 vs 24.1 ± 6.4, P < 0.05); GBEF and GBER decreased obviously after operation (13.1 ± 5.4 vs 32.3 ± 16.3, 0.7 ± 0.3 vs 1.4 ± 0.8, P < 0.01). The preceding parameters in VCE group had no significant difference before and after operation (P > 0.05).

CONCLUSION: The gallbladder tension weakens obviously in interdigestive phase after the vagus is excised; the gallbladder contraction delays, and the motor function weakens obviously after meals.

Gallbladder motility in patients with hepatic cirrhosis before and after portal azygous disconnection

AIM: To determine and compare the effect of vagus nerve on gallbladder motility in patients with hepatic cirrhosis before and after portal azygous disconnection (PAD).

METHODS: PAD operation (or Hassab’s operation) was performed on 18 patients with portal hypertension, and anterior and posterior vagal trunks were cut. On d 3 before operation and d 10 after operation, ^99mTc-EHIDA 185 MBq was administered intravenously to the patients, and scintigraphy was performed at 0.25 min/frame. A standard fat meal was administered 30 min after scintigraphy, and dynamic imaging was performed 60 min after the fat meal. Following appearance of the region of interest (ROI) in gallbladder, the time-activity curve of ROI was established. The following seven parameters were used: Radioactivity at 30 min after injection of ^99mTc-EHIDA (RC 30min), bile emptying fraction (EF), bile emptying period (EP), emptying rate (ER), latent period (LP), latent period radiocounting increment (LI), and latent period radiocounting increment rate (LR).

RESULTS: The RC 30 min decreased significantly after operation, compared with that before operation (2 693.6 ± 2 406.9 vs 5 606.8 ± 2 625.4, P < 0.05). The radiocounting of gallbladder increased gradually during LP. LP after operation was significantly longer than that before operation (13.36 ± 5.92 vs 2.24 ± 1.48, P < 0.01). LI and LR after operation were significantly higher than those before operation (2 861.62 ± 028.3 vs 331.21 ± 421.02, and 113.42 ± 49.52 vs 7.57 ± 10.75, respectively, both P < 0.01). EP after operation was significantly shorter than that before operation (18.5 ± 6.3 vs 24.1 ± 6.4, P < 0.05). EF and ER after operation were significantly lower than those before operation (13.1 ± 5.4 vs 32.3 ± 16.3, and 0.7 ± 0.3 vs 1.4 ± 0.8, respectively, both P < 0.01).

CONCLUSION: PAD operation is a good clinical model in studying the effect of vagus on gallbladder motility. The gallbladder tension after PAD operation decreases significantly during the interdigestive phase. The latent period of gallbladder contraction prolongs and the motility weakens apparently after a standard fat meal. Human vagus influences the gallbladder motility, and cutting of the nerve inhibits the gallbladder motility.

Differential effects of motilin on interdigestive motility of the human gastric antrum, pylorus, small intestine and gallbladder

Motilin was infused in this study with the aim of examining refractory characteristics for motilin stimulation of antral phase III and fasting gallbladder emptying. Moreover, interdigestive pyloric and small intestinal motility from duodenum to ileum were studied, as these may be target organs for motilin. Eight fasting, healthy male volunteers received, on separate subsequent days, repeated infusions of 13leucine-motilin (8 pmol (kg min)(-1) for 5 min) or saline at 30 min after phase IIIs in the duodenum. Interdigestive motility of the antrum, pylorus, duodenum, jejunum and ileum was measured for maximum 10 h by using a 21-lumen perfused catheter. Gallbladder motility was measured by ultrasonography. Motilin infusions induced antral phase IIIs, but only after a preceding phase III of duodenal origin. Under this condition, time-interval to phase III at the duodenal recording site was 30 +/- 13 (SEM) min after motilin, compared with 79 +/- 14 min after saline (P < 0.01), and compared with 121 +/- 13 min for motilin infusion following an antral phase III (P < 0.001). Motilin did not affect small intestinal motility or isolated pyloric pressure waves (IPPWs). However, the number of IPPWs was significantly affected by the origin of the preceding phase III, irrespective of whether motilin or saline was infused. Gallbladder volume decreased significantly within 10 min after each motilin infusion. We conclude that this study clearly demonstrates differential regional effects of motilin. Motilin initiates antral phase IIIs, but stimulation is subject to a refractory period which is clearly prolonged after a preceding antral phase III. Motilin induced gallbladder emptying, however, is not subject to a refractory state. Small intestinal phase IIIs as well as pyloric IPPWs are not affected by motilin.