Moderate physical exercise and ATP modulate the P2X7 receptor and improve cisplatin-induced gastric emptying delay in rats.

Patients undergoing chemotherapy with cisplatin commonly present gastrointestinal effects such as constipation and gastric emptying (GE) delay. Both the purinergic system and physical exercise modulate the gastrointestinal (GI) tract. In the current study, we investigated the role of ATP, physical exercise, and P2X7 receptor blocking on GE delay induced by cisplatin in rats. Male rats were divided into the following groups: control (C), cisplatin (Cis), exercise (Ex), Brilliant Blue G (BBG), ATP, Cis+Ex, Cis+ATP, Cis+BBG, Cis+Ex+BBG, Cis+Ex+BBG+ATP, and Cis+ATP+BBG. GE delay was induced by treatment with 1 mg/kg cisplatin (1 time/week for 5 weeks, ip). The moderate physical exercise was swimming (1 h/day, 5 days/week for 5 weeks). At the end of the treatment or exercise and 30 min before the GE assessment, some groups received BBG (50 mg/kg, sc) or ATP (2 mg/kg, sc). Then, GE was assessed after a 10-min postprandial period. Chronic use of Cis decreased GE delay (P<0.05) compared to the control group. Both exercise and ATP prevented (P<0.05) GE delay compared to Cis. The pretreatment with BBG significantly inhibited (P<0.05) the effect of exercise and ATP. On the other hand, the association between exercise and ATP reversed (P<0.05) the effect of the BBG and prevented GE delay. Therefore, we suggest that both exercise and treatment with ATP activate P2X7 receptors and prevent GE delay induced by cisplatin in rats.

Resolution of severe gastroparesis induced by parasympathetic surge following facial trauma: a case report.

BACKGROUND: Gastroparesis is a condition that affects the motility of the gastrointestinal (GI) tract, causing a delay in the emptying process and leading to nausea, vomiting, bloating, and upper abdominal pain. Motility treatment along with symptom management can be done using antiemetics or prokinetics. This study highlights the diagnostic and therapeutic challenges of gastroparesis and suggests a potential link between facial trauma and symptom remission, indicating the need for further investigation. CASE PRESENTATION: A 46-year-old Hispanic man with hypertension, type 2 diabetes (T2D), and hyperlipidemia on amlodipine 10 mg, lisinopril 5 mg, empagliflozin 25 mg, and insulin glargine presented with a diabetic foot ulcer with probable osteomyelitis. During hospitalization, the patient developed severe nausea and vomiting. The gastroenterology team advised continuing antiemetic medicine and trying very small sips of clear liquids. However, the patient didn't improve. Therefore, the gastroenterology team was contacted again. They advised having stomach emptying tests to rule out gastroparesis as the source of emesis. In addition, they recommended continuing metoclopramide, and starting erythromycin due to inadequate improvement. Studies found a 748-min stomach emptying time. Normal is 45-90 min. An uneventful upper GI scope was done. Severe gastroparesis was verified, and the gastroenterology team advised a percutaneous jejunostomy or gastric pacemaker for gastroparesis. Unfortunately, the patient suffered a mechanical fall resulting in facial trauma. After the fall, the patient's nausea eased, and emesis stopped. He passed an oral liquids trial after discontinuation of erythromycin and metoclopramide. CONCLUSION: This case exemplifies the difficulties in diagnosing and treating gastroparesis. An interesting correlation between parasympathetic surges and recovery in gastroparesis may be suggested by the surprising remission of symptoms following face injuries.

Inhibition of calcium-sensing receptor by its antagonist promotes gastrointestinal motility in a Parkinson's disease mouse model.

BACKGROUND: The Calcium-sensing receptor (CaSR) participates in the regulation of gastrointestinal (GI) motility under normal conditions and might be involved in the regulation of GI dysmotility in patients with Parkinson's disease (PD). METHODS: CaSR antagonist-NPS-2143 was applied in in vivo and ex vivo experiments to study the effect and underlying mechanisms of CaSR inhibition on GI dysmotility in the MPTP-induced PD mouse model. FINDINGS: Oral intake of NPS-2143 promoted GI motility in PD mice as shown by the increased gastric emptying rate and shortened whole gut transit time together with improved weight and water content in the feces of PD mice, and the lack of influence on normal mice. Meanwhile, the number of cholinergic neurons, the proportion of serotonergic neurons, as well as the levels of acetylcholine and serotonin increased, but the numbers of nitrergic and tyrosine hydroxylase immunoreactive neurons, and the levels of nitric oxide synthase and dopamine decreased in the myenteric plexus in the gastric antrum and colon of PD mice in response to NPS-2143 treatment. Furthermore, the numbers of c-fos positive neurons in the nucleus tractus solitarius (NTS) and cholinergic neurons in the dorsal motor nucleus of the vagus (DMV) increased in NPS-2143 treated PD mice, suggesting the involvement of both the enteric (ENS) and central (CNS) nervous systems. However, ex vivo results showed that NPS-2143 directly inhibited the contractility of antral and colonic strips in PD mice via a non-ENS mediated mechanism. Further studies revealed that NPS-2143 directly inhibited the voltage gated Ca2+ channels, which might, at least in part, explain its direct inhibitory effects on the GI muscle strips. INTERPRETATION: CaSR inhibition by its antagonist ameliorated GI dysmotility in PD mice via coordinated neuronal regulation by both ENS and CNS in vivo, although the direct effects of CaSR inhibition on GI muscle strips were suppressive.

Hypoglycemic effects of mountain caviar extract and inhibitory mechanism of saponins, including momordin Ic, on glucose absorption.

Mountain caviar is a fruit of Kochia scoparia that contains momordin Ic as a major saponin constituent. Its extract (MCE) has been shown to suppress blood glucose elevations in the human oral glucose tolerance test (OGTT) as well as increases in blood glucose in OGTT, gastric emptying (GE), and glucose incorporation in the small intestine in rats. However, the effects of MCE and momordin Ic on glucose absorption in mice and these action mechanisms have not been examined for more than 2 decades. Therefore, we herein investigated the effects of MCE, its saponin fraction, and momordin Ic on blood glucose elevations in mice. Mouse blood glucose elevation tests were performed on carbohydrate-loaded mice. The mountain caviar saponin fraction significantly delayed blood glucose elevations in glucose-, sucrose-, and soluble starch-loaded mice. In glucose-loaded mice, the saponin fraction, MCE, and momordin Ic significantly suppressed rapid glucose elevations after glucose loading, but not sucrose loading. A mouse GE study was performed by loading with glucose and phenolphthalein solution. Momordin Ic and MCE strongly suppressed mouse GE. Intestinal glucose absorption was evaluated by the incorporation of 2-deoxyglucose (2-DG) into Caco-2 cell layers and mouse duodenum wall vesicles. The results obtained showed that momordin Ic inhibited the incorporation of 2-DG into Caco-2 cells and mouse duodenum vesicles. Collectively, these results suggest that MCE, particularly the principal saponin, momordin Ic, preferably suppressed glucose-induced blood glucose elevations and delayed carbohydrate-induced glucose elevations in mice. The underlying mechanism was found to involve the suppression of GE and intestinal glucose absorption.

In Vitro Simulation of the Fasted Gastric Conditions and Their Variability to Elucidate Contrasting Properties of the Marketed Dabigatran Etexilate Pellet-Filled Capsules and Loose Pellets.

Variability of the gastrointestinal tract is rarely reflected in in vitro test protocols but often turns out to be crucial for the oral dosage form performance. In this study, we present a generation method of dissolution profiles accounting for the variability of fasted gastric conditions. The workflow featured 20 biopredictive tests within the physiological variability. The experimental array was constructed with the use of the design of experiments, based on three parameters: gastric pH and timings of the intragastric stress event and gastric emptying. Then, the resulting dissolution profiles served as a training data set for the dissolution process modeling with the machine learning algorithms. This allowed us to generate individual dissolution profiles under a customizable gastric pH and motility patterns. For the first time ever, we used the method to successfully elucidate dissolution properties of two dosage forms: pellet-filled capsules and bare pellets of the marketed dabigatran etexilate product Pradaxa. We showed that the dissolution of capsules was triggered by mechanical stresses and thus was characterized by higher variability and a longer dissolution onset than observed for pellets. Hence, we proved the applicability of the method for the in vitro and in silico characterization of immediate-release dosage forms and, potentially, for the improvement of in vitro-in vivo extrapolation.

Gastrointestinal dysfunction in the valproic acid induced model of social deficit in rats.

Autism spectrum disorder (ASD) has increased in incidence over the past several decades, and is associated with a range of co-morbidities including gastrointestinal (GI) dysfunctions including gastroesophageal reflux, abdominal pain, bloating, constipation and/or diarrhea. Several animal models have been used that replicate several aspects of ASD but no single model has been able to replicate the entire disease pathophysiology. In humans, prenatal exposure to valproic acid (VPA) has been identified as a significant risk factor and rodent models have shown that in utero VPA exposure leads to behavioral deficits in offspring. The present study aimed to investigate whether in utero exposure to VPA induces GI dysfunction in rats. Timed pregnant Sprague-Dawley rats were injected with a single dose of VPA at embryonic day 12.5. Both male and female offspring subsequently underwent behavioral studies and assessment of GI function in adulthood. In utero VPA treatment induced social deficits in both male and female offspring, decreasing sociability and social novelty. Histological examination showed that VPA treated offspring had decreased thickness of GI muscle and mucosa, while immunohistochemical studies showed a decrease in myenteric neuron number in the fundus. Functional studies showed that both male and female VPA offspring had a delay in gastric emptying compared to vehicle treated offspring. Results of the current study suggest that the rat VPA model of behavioral deficits may be a convenient model by which both mechanistic and functional insights into GI dysfunction may be studied.

TAAR1 agonist ulotaront delays gastric emptying of solids in patients with schizophrenia and concurrent metabolic syndrome with prediabetes.

BACKGROUND: Metabolic syndrome (MetS), which can be induced or exacerbated by the current class of antipsychotic drugs, is highly prevalent in patients with schizophrenia and presents significant challenges to lifetime disease management. Supported by initial clinical results, trace amine-associated receptor 1 (TAAR1) agonists have emerged as potential novel treatments for schizophrenia. Notably, non-clinical studies have also shown weight-lowering and glucoregulatory effects of TAAR1 agonists, including the investigational agent ulotaront. However, the translatability of these findings to humans has not been adequately assessed. Given that delayed gastric emptying (GE) was identified as a potential mechanism contributing to the metabolic benefits of TAAR1 agonists in rodents, the aim of this study was to evaluate the effect of ulotaront on GE in patients with schizophrenia and concurrent MetS with prediabetes. METHODS: Patients with schizophrenia were randomized to receive a single oral dose of ulotaront (150 mg) and their previous antipsychotic (PA) in an open-label, crossover, two-sequence design (NCT05402111). Eligible participants fulfilled at least three of five MetS criteria and had prediabetes defined by elevated glycated haemoglobin (5.7-6.4%) and/or fasting homeostatic model assessment of insulin resistance (i.e. ≥2.22). Following an overnight fast and 4 h post-dose, participants ingested a 99mTc-sulphur colloid radiolabelled egg meal (320 kcal, 30% fat). GE was measured by scintigraphy over 4 h. Endpoints included GE of solids half-time (T1/2) and percentage gastric retention at 1, 2 and 4 h. RESULTS: Thirty-one adults were randomized and 27 completed the study. Ulotaront significantly delayed GE of solids [median GE T1/2 ulotaront at 139 min (119, 182) vs. the participant's PA of 124 min (109, 132), p = .006]. A significant increase in gastric retention was seen in the ulotaront versus the PA group at 1 h (80% vs. 75%, p = .015), 2 h (61% vs. 50%, p = .023) and 4 h (17% vs. 7%, p = .002) post-meal. CONCLUSION: Ulotaront delayed the GE of solids in patients with schizophrenia and concurrent MetS with prediabetes. Additional studies are needed to assess whether treatment with TAAR1 agonists is associated with weight loss and glucoregulatory improvement.

Effects of corticotropin-releasing hormone on gastric electrical activity and sensorimotor function in healthy volunteers: a double-blinded crossover study.

Biopsychosocial factors are associated with disorders of gut-brain interaction (DGBI) and exacerbate gastrointestinal symptoms. The mechanisms underlying pathophysiological alterations of stress remain unclear. Corticotropin-releasing hormone (CRH) is a central regulator of the hormonal stress response and has diverse impact on different organ systems. The aim of the present study was to investigate the effects of peripheral CRH infusion on meal-related gastrointestinal symptoms, gastric electrical activity, and gastric sensorimotor function in healthy volunteers (HVs). In a randomized, double-blinded, placebo-controlled, crossover study, we evaluated the effects of CRH on gastric motility and sensitivity. HVs were randomized to receive either peripheral-administered CRH (100 µg bolus + 1 µg/kg/h) or placebo (saline), followed by at least a 7-day washout period and assignment to the opposite treatment. Tests encompassed saliva samples, gastric-emptying (GE) testing, body surface gastric mapping (BSGM, Gastric Alimetry; Alimetry) to assess gastric myoelectrical activity with real-time symptom profiling, and a gastric barostat study to assess gastric sensitivity to distention and accommodation. Twenty HVs [13 women, mean age 29.2 ± 5.3 yr, body mass index (BMI) 23.3 ± 3.8 kg/m2] completed GE tests, of which 18 also underwent BSGM measurements during the GE tests. The GE half-time decreased significantly after CRH exposure (65.2 ± 17.4 vs. 78.8 ± 24.5 min, P = 0.02) with significantly increased gastric amplitude [49.7 (34.7-55.6) vs. 31.7 (25.7-51.0) µV, P < 0.01], saliva cortisol levels, and postprandial symptom severity. Eleven HVs also underwent gastric barostat studies on a separate day. However, the thresholds for discomfort during isobaric distensions, gastric compliance, and accommodation did not differ between CRH and placebo.NEW & NOTEWORTHY In healthy volunteers, peripheral corticotropin-releasing hormone (CRH) infusion accelerates gastric-emptying rate and increases postprandial gastric response, accompanied by a rise in symptoms, but does not alter gastric sensitivity or meal-induced accommodation. These findings underscore a significant link between stress and dyspeptic symptoms, with CRH playing a pivotal role in mediating these effects.

Perioperative management of patients on glucagon-like peptide-1 receptor agonists.

PURPOSE OF REVIEW: To summarize the mechanism of action, clinical outcomes, and perioperative implications of glucagon-like peptide-1 receptor agonists (GLP-1-RAs). Specifically, this review focuses on the available literature surrounding complications (primarily, bronchoaspiration) and current recommendations, as well as knowledge gaps and future research directions on the perioperative management of GLP-1-RAs. RECENT FINDINGS: GLP-1-RAs are known to delay gastric emptying. Accordingly, recent case reports and retrospective observational studies, while anecdotal, suggest that the perioperative use of GLP-1-RAs may increase the risk of bronchoaspiration despite fasting intervals that comply with (and often exceed) current guidelines. As a result, guidelines and safety bulletins have been published by several Anesthesiology Societies. SUMMARY: While rapidly emerging evidence suggests that perioperative GLP-1-RAs use is associated with delayed gastric emptying and increased risk of bronchoaspiration (particularly in patients undergoing general anesthesia and/or deep sedation), high-quality studies are needed to provide definitive answers with respect to the safety and duration of preoperative drug cessation, and optimal fasting intervals according to the specific GLP-1-RA agent, the dose/duration of administration, and patient-specific factors. Meanwhile, clinicians must be aware of the potential risks associated with the perioperative use of GLP-1-RAs and follow the recommendations put forth by their respective Anesthesiology Societies.

Gastric peroral endoscopic myotomy versus botulinum toxin injection for the treatment of refractory gastroparesis: results of a double-blind randomized controlled study.

INTRODUCTION: Gastric peroral endoscopic myotomy (G-POEM) is a promising technique for treating refractory gastroparesis. We present the first double-blind randomized study comparing the clinical efficacy of G-POEM versus pyloric botulinum toxin injection (BTI). METHODS: This randomized study, conducted in two expert centers, enrolled patients with refractory gastroparesis, medically managed for >6 months and confirmed by gastric emptying scintigraphy (GES), into two groups, G-POEM versus BTI, with follow-up of 1 year. The primary end point was the 3-month clinical efficacy, defined as a >1-point decrease in the mean Gastroparesis Cardinal Symptom Index (GCSI) score. Secondary end points were: 1-year efficacy, GES evolution, adverse events, and quality of life. RESULTS: 40 patients (22 women; mean age 48.1 [SD 17.4]), with mean symptom duration of 5.8 (SD 5.7) years, were randomized. Etiologies included idiopathic (n=18), diabetes (n=11), postoperative (n=6), and mixed (n=4). G-POEM showed a higher 3-month clinical success than BTI (65% vs. 40%, respectively; P=0.10), along with non-significantly higher 1-year clinical success (60% vs. 40%, respectively) on intention-to-treat analysis. The GCSI decreased in both groups at 3 months and 1 year. Only three minor adverse events occurred in the G-POEM group. The GES improvement rate was 72% in the G-POEM group versus 50% in the BTI group (non-significant). CONCLUSION: G-POEM seems to have a higher clinically relevant success rate than BTI, but this was not statistically demonstrated. This study confirms the interest in treatments targeting the pylorus, either mechanically or chemically, for managing refractory gastroparesis.

The underlying rationality of Chinese medicine herb pair Coptis chinensis and Dolomiaea souliei: From the perspective of metabolomics and intestinal function.

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Coptis chinensis (RC) and Dolomiaea souliei (VR) has long been used as a classic herb pair for the treatment of gastrointestinal diseases, but the underlying mechanisms remain unknown. MATERIALS AND METHODS: In this study, the rationality of evidence-based RC and VR combination was explored from the perspective of metabolism, gut microbiota and gastrointestinal function. RESULTS: After 5 weeks treatment, VR extracts (700 mg/kg) and RC alkaloids (800 mg/kg) showed no toxic effect on mice. However, RC administration significantly decreased the body weight of mice. Gastric emptying, gastrointestinal motility function and the absorption of FITC dextran were retarded in the mice of RC group, taking RC along with low dose VR (RC-VRL) and high dose VR (RC-VRH) reversed the impaired gastrointestinal function caused by RC. RC administration significantly increased villus height/crypt depth value. Notably, VR administration increased the number of crypts in mice ileum and reduced villus height/crypt depth value in VR and RC combination group. RC treatment significantly increased the expression of occludin compared to NC group; RC-VRL treatment reversed this tendency. While, VR administration increased ZO1 expression by 99.4% compared to NC mice. As for gut microbiota, RC gavage decreased the gut microbiota diversity, but gut microbiota in VR group was similar to NC group, and VR and RC combination increased gut microbiota diversity. RC administration obviously increased the proportion of Akkermansia muciniphila, Bacteroides thetaiotaomicron, Parabacteroides distasonis, and Escherichia coli, compared to NC mice. VR treatment increased the richness of Bacteroides thetaiotaomicron, Parabacteroides distasonis. RC-VRL and RC-VRH treatment dose-dependently increased the richness of Rikenellaceae RC9, Lactobacillus, and decreased the abundance of Psychrobacter, Bacteroides and Ruminococcus in mice. Serum metabolomic analysis revealed that RC gavage significantly down regulated 76 metabolites and up regulated 31 metabolites. VR treatment significantly down regulated 30 metabolites and up regulated 12 metabolites. Weight loss caused by RC may attribute to the elevated methylxanthine level in mice. The potential adverse effects caused by high dose RC intake may partially alleviate by high serum contents of adenosine, inosine and urolithin A resulted from VR coadministration. CONCLUSION: VR may alleviate RC caused "fluid retention" via normalizing gastrointestinal function, gut microbiota and modulating the perturbed metabolism.

Changes in glycemic variability, gastric emptying and vascular endothelial function after switching from twice-daily to once-weekly exenatide in patients with type 2 diabetes: a subpopulation analysis of the twin-exenatide study.

BACKGROUND: We investigated the changes in blood glucose fluctuation, gastric emptying, and vascular endothelial function by switching from an exenatide twice-daily formulation (BID) to a once-weekly formulation (QW) since the evaluation of postprandial glucose excursion and glycemic variability (GV) by continuous glucose monitoring (CGM) after switching was lacking. METHODS: Twenty-nine patients with type 2 diabetes treated with exenatide BID were included in this study and switched to exenatide QW for 24 weeks. GV assessed by CGM, gastric emptying (by 13 C-acetate breath test) and vascular endothelial function (by reactive hyperemia - peripheral arterial tonometry) were evaluated at baseline and 24 weeks after switching. RESULTS: HbA1c decreased significantly from the baseline to week 24, while postprandial glucose levels after breakfast and dinner significantly increased (both P <0.05). However, the increases in GV indices were modest and not statistically significant at week 24. Vascular endothelial function was also not significantly changed after switching (P >0.05). Gastric emptying was significantly accelerated at week 24 (Tmax 83.4 ± 12.1 min vs. 58.2 ± 16.4 min) (P <0.001) and correlated with increased postprandial glucose levels after breakfast and dinner (both P <0.05). CONCLUSIONS: Despite the increase in postprandial glucose associated with accelerated gastric emptying after switching from exenatide BID to QW, change in GV was modest and no significant deterioration in vascular endothelial function was observed after switching. These results support the superiority of treatment with exenatide QW over exenatide BID in clinical practice; however, attention should be paid to the monitoring and management of postprandial glucose levels when selecting exenatide QW. TRIAL REGISTRATION: Clinical trial registry number; UMIN000016390 and jRCTs031180320 . Approval date of Registry and the Registration: December 12, 2014.

Oral lactate slows gastric emptying and suppresses appetite in young males.

BACKGROUND: Lactate serves as an alternative energy fuel but is also an important signaling metabolite. We aimed to investigate whether oral lactate administration affects appetite-regulating hormones, slows gastric emptying rate, and dampens appetite. METHODS: Ten healthy male volunteers were investigated on two separate occasions: 1) following oral ingestion of D/L-Na-lactate and 2) following oral ingestion of isotonic iso-voluminous NaCl and intravenous iso-lactemic D/L-Na-lactate infusions. Appetite was evaluated by questionnaires and ad libitum meal tests were performed at the end of each study day. Gastric emptying rate was evaluated using the acetaminophen test. RESULTS: Plasma concentrations of growth differential factor 15 (GDF15, primary outcome) increased following oral and iv administration of lactate (p < 0.001) with no detectable difference between interventions (p = 0.15). Oral lactate administration lowered plasma concentrations of acylated ghrelin (p = 0.02) and elevated glucagon like peptide-1 (GLP-1, p = 0.045), insulin (p < 0.001), and glucagon (p < 0.001) compared with iv administration. Oral lactate administration slowed gastric emptying (p < 0.001), increased the feeling of being "full" (p = 0.008) and lowered the "anticipated future food intake" (p = 0.007) compared with iv administration. Food intake during the ad libitum meal test did not differ between the two study days. CONCLUSION: Oral lactate administration has a direct effect on the upper gastrointestinal tract, affecting gut hormone secretion, motility and appetite sensations which cannot be mediated through lactate in the systemic circulation alone. These data suggest that compounds rich in lactate may be useful in the treatment of metabolic disease. CLINICAL TRIAL REGISTRY NUMBER: NCT0429981, https://clinicaltrials.gov/ct2/show/NCT04299815.

Formulation, Optimization, in vitro and in-vivo evaluation of levofloxacin hemihydrate Floating Tablets

Abstract The objective of the present investigation was to design, optimize and characterize the gastro retentive floating levofloxacin tablets and perform in-vivo evaluation using radiographic imaging. The floating tablets were prepared by using polymers i.e hydroxy propyl methyl cellulose (HPMC-K4M) and carbopol-940 individually and in combination by nonaquous granulation method. All the Formulations were evaluated for swelling index (S.I), floating behavior and in-vitro drug release kinetics. The compatibility study of levofloxacin with other polymers was investigated by FTIR, DSC, TGA and XRD. Results from FTIR and DSC revealed no chemical interaction amongst the formulation components. The optimized formulation (F11) showed floating lag time (FLT), total floating time (TFT) swelling index (S.I) of 60 sec, >16h and approximately 75 %, respectively. Moreover, F11 showed zero order levofloxacin release in simulated gastric fluid over the period of 6 h. X-ray studies showed that total buoyancy time was able to delay the gastric emptying of levofloxacin floating tablets in rabbits for more than 4 hours. In conclusion the optimized formulation (F11) can be used for the sustained delivery of levofloxacin for the treatment of peptic ulcer.

The Short-Term Effects and Tolerability of Low-Viscosity Soluble Fibre on Gastroparesis Patients: A Pilot Clinical Intervention Study.

Gastroparesis is a motility disorder that causes severe gastric symptoms and delayed gastric emptying, where the majority of sufferers are females (80%), with 29% of sufferers also diagnosed with Type-1 or Type-2 diabetes. Current clinical recommendations involve stringent dietary restriction and includes the avoidance and minimization of dietary fibre. Dietary fibre lowers the glycaemic index of food, reduces inflammation and provides laxation. Lack of dietary fibre in the diet can affect long-term gastrointestinal health. Our previously published rheological study demonstrated that "low-viscosity" soluble fibres could be a potentially tolerable source of fibre for the gastroparetic population. A randomised controlled crossover pilot clinical study was designed to compare Partially-hydrolysed guar gum or PHGG (test fibre 1), gum Arabic (test fibre 2), psyllium husk (positive control) and water (negative control) in mild-to-moderate symptomatic gastroparesis patients (requiring no enteral tube feeding). The principal aim of the study was to determine the short-term physiological effects and tolerability of the test fibres. In n = 10 female participants, post-prandial blood glucose, gastroparesis symptoms, and breath test measurements were recorded. Normalized clinical data revealed that test fibres PHGG and gum Arabic were able to regulate blood glucose comparable to psyllium husk, while causing far fewer symptoms, equivalent to negative control. The test fibres did not greatly delay mouth-to-caecum transit, though more data is needed. The study data looks promising, and a longer-term study investigating these test fibres is being planned.

MECHANISMS IN ENDOCRINOLOGY: The physiology of neuronostatin.

In 2008, the first evidence of a new hormone called neuronostatin was published. The hormone was discovered using a bioinformatic method and found to originate from the same preprohormone as somatostatin. This small peptide hormone of 13 amino acids and a C-terminal amidation was soon found to exert pleiotropic physiological effects. In animal studies, neuronostatin has been shown to reduce food intake and delay gastric emptying and gastrointestinal transit. Furthermore, neuronostatin has been shown to affect glucose metabolism by increasing glucagon secretion during situations when glucose concentrations are low. Additionally, neuronostatin has been shown to affect neural tissue and cardiomyocytes by suppressing cardiac contractility. The effects of neuronostatin have not yet been delineated in humans, but if the effects found in animal studies translate to humans it could position neuronostatin as a promising target in the treatment of obesity, hypertension and diabetes. In this review, we describe the discovery of neuronostatin and the current understanding of its physiological role and potential therapeutic applicability.

Supraphysiological effects of pancreatic polypeptide on gastric motor function and nutrient tolerance in humans.

Pancreatic polypeptide (PP) is known to affect food intake. In this exploratory study, we set out to investigate its supraphysiological effect on food tolerance, gastric accommodation, and emptying. In 12 healthy volunteers, 0, 3, or 10 pmol*kg-1 *min-1 PP was administered intravenously (PP0, PP3 or PP10). Thirty minutes thereafter, nutrient drink infusion (60 ml*min-1 ) through a nasogastric feeding tube was started until maximum satiation. Gastric accommodation was assessed by measuring the intragastric pressure (IGP; nasogastric manometry). In a separate test, the effect of PP0 or PP10 on gastric emptying was tested in 10 healthy volunteers and assessed using the 13 C breath test. Results are presented as mean ± SEM, and p < 0.05 was considered significant. For the IGP test, PP increased ingested nutrient volume: 886 ± 93, 1059 ± 124, and 1025 ± 125 ml for PP0, PP3, and PP10, respectively (p = 0.048). In all groups, Nadir IGP values were reached upon food intake (transformed values: 1.5 ± 0.2, 1.7 ± 0.3, and 1.6 ± 0.3 mmHg for PP0, PP3, and PP10, respectively; NS) to return to baseline thereafter. For the gastric emptying study, volunteers ingested a similar nutrient volume: 802 ± 119 and 1089 ± 128 ml (p = 0.016), and gastric half-emptying time was 281 ± 52 and 249 ± 37 min for PP0 and PP10, respectively (NS). No significant correlation between tolerated nutrient volume and IGP drop (R² < 0.01; p = 0.88 for PP0 vs. PP3 and R² =0.07; p = 0.40 for PP0 vs. PP10, respectively) or gastric half-emptying time (R² = 0.12; p = 0.32) was found. A supraphysiological PP dose enhances food tolerance; however, this effect is not mediated through gastric motility. CLINICAL TRIAL REGISTRY NUMBER: NCT03854708 is obtained from clinicaltrials.gov.

Comparing the Effect of Neostigmine and Metoclopramide on Gastric Residual Volume of Mechanically Ventilated Patients in Intensive Care Unit: A Double-Blind Randomized Clinical Trial.

INTRODUCTION: The gastric residual volume (GRV) monitoring in patients with mechanical ventilation (MV) is a common and important challenge. The purpose of this study was to compare the effect of neostigmine and metoclopramide on GRV among MV patients in the intensive care unit (ICU). METHODS: In a double-blind randomized clinical trial, a total of 200 mechanically ventilated ICU patients with GRV > 120 ml (6 hours after the last gavage) were randomly assigned into two groups (A and B) with 100 patients in each group. Patients in groups A and B received intravenous infusion of neostigmine at a dose of 2.5 mg/100 ml normal saline and metoclopramide at a dose of 10 mg/100 ml normal saline, within 30 minutes, respectively. GRV was evaluated 5 times for each patient, once before the intervention and 4 times (at 3, 6, 9, and 12 hours) after the intervention. In addition, demographic characteristics including age and gender, as well as severity illness based on the sequential organ failure assessment score (SOFA), were initially recorded for all patients. RESULTS: After adjusting of demographic and clinical characteristics (age, gender, and SOFA score), the generalized estimating equation (GEE) model revealed that neostigmine treatment increased odds of GRV improvement compared to the metoclopramide group (OR = 2.45, 95% CI: 1.60-3.76, P < 0.001). However, there is a statistically significant time trend (within-subject differences or time effect) regardless of treatment groups (P < 0.001). CONCLUSION: According to the results, although neostigmine treatment significantly improved GRV in more patients in less time, within 12 hours of treatment, all patients in both groups had complete recovery. Considering that there was no significant difference between the two groups in terms of side effects, it seems that both drugs are effective in improving the GRV of ICU patients.