Body weight in patients with idiopathic gastroparesis

BACKGROUND

The classic clinical picture of gastroparesis is a symptomatic patient losing weight. In addition, a number of patients with delayed gastric emptying are obese and/or gaining weight. Our aim was to investigate the factors impacting body weight in patients with idiopathic gastroparesis.

METHODS

In patients with idiopathic gastroparesis, detailed history and weight were acquired at enrollment and after 48 weeks. Questionnaires assessed symptoms, food intake, physical activity, and quality of life. Patients underwent laboratory testing, gastric emptying scintigraphy, and water load testing.

RESULTS

Of 138 patients with idiopathic gastroparesis, 10% were underweight (BMI < 18.5), 39% were normal weight (BMI 18.5-25), 20% were overweight with BMI 25 to 30 kg/m² , and 29% were obese with BMI > 30 kg/m² . Body weight at enrollment was positively associated with oral caloric consumption (P < .001), following a gastroparesis diet (P = .04), nutrition consultation (P = .001), upper abdominal pain (P = .01); and negatively associated with energy expenditure (P = .05), alcohol use (P = .003) and severity of bloating (P < .001). When followed over 48 weeks, 53% patients stayed stable (within 5% of baseline weight), 30% gained, and 17% lost weight. Weight gain over 48 weeks was positively associated with oral caloric consumption (P = .003) and constipation severity (P = .005) at enrollment, and negatively associated with lower abdominal pain severity (P = .007) at enrollment, and associated with improvement in inability to finish meal score (P < .001) at 48 weeks.

CONCLUSIONS

In this series of patients with idiopathic gastroparesis, 10% were underweight whereas 29% were obese. Over 48 weeks, 30% of patients increased their body weight ≥ 5%. Diet, activity, and symptoms are important factors associated with body weight in patients with idiopathic gastroparesis.

Vagally Mediated Gut-Brain Relationships in Appetite Control-Insights from Porcine Studies

Signals arising from the upper part of the gut are essential for the regulation of food intake, particularly satiation. This information is supplied to the brain partly by vagal nervous afferents. The porcine model, because of its sizeable gyrencephalic brain, omnivorous regimen, and comparative anatomy of the proximal part of the gut to that of humans, has provided several important insights relating to the relevance of vagally mediated gut-brain relationships to the regulation of food intake. Furthermore, its large size combined with the capacity to become obese while overeating a western diet makes it a pivotal addition to existing murine models, especially for translational studies relating to obesity. How gastric, proximal intestinal, and portal information relating to meal arrival and transit are encoded by vagal afferents and their further processing by primary and secondary brain projections are reviewed. Their peripheral and central plasticities in the context of obesity are emphasized. We also present recent insights derived from chronic stimulation of the abdominal vagi with specific reference to the modulation of mesolimbic structures and their role in the restoration of insulin sensitivity in the obese miniature pig model.

Acceleration of Gastric Emptying by Insulin-Induced Hypoglycemia is Dependent on the Degree of Hypoglycemia

CONTEXT

Hypoglycemia is a major barrier to optimal glycemic control in insulin-treated diabetes. Recent guidelines from the American Diabetes Association have subcategorized "non-severe" hypoglycemia into level 1 (<3.9 mmol/L) and 2 (<3 mmol/L) hypoglycemia. Gastric emptying of carbohydrate is a major determinant of postprandial glycemia but its role in hypoglycemia counter-regulation remains underappreciated. "Marked" hypoglycemia (~2.6 mmol/L) accelerates gastric emptying and increases carbohydrate absorption in health and type 1 diabetes, but the impact of "mild" hypoglycemia (3.0-3.9 mmol/L) is unknown.

OBJECTIVE

To determine the effects of 2 levels of hypoglycemia, 2.6 mmol/L ("marked") and 3.6 mmol/L ("mild"), on gastric emptying in health.

DESIGN, SETTING, AND SUBJECTS

Fourteen healthy male participants (mean age: 32.9 ± 8.3 years; body mass index: 24.5 ± 3.4 kg/m2) from the general community underwent measurement of gastric emptying of a radiolabeled solid meal (100 g beef) by scintigraphy over 120 minutes on 3 separate occasions, while blood glucose was maintained at either ~2.6 mmol/L, ~3.6 mmol/L, or ~6 mmol/L in random order from 15 minutes before until 60 minutes after meal ingestion using glucose-insulin clamp. Blood glucose was then maintained at 6 mmol/L from 60 to 120 minutes on all days.

RESULTS

Gastric emptying was accelerated during both mild (P = 0.011) and marked (P = 0.001) hypoglycemia when compared to euglycemia, and was more rapid during marked compared with mild hypoglycemia (P = 0.008). Hypoglycemia-induced gastric emptying acceleration during mild (r = 0.57, P = 0.030) and marked (r = 0.76, P = 0.0014) hypoglycemia was related to gastric emptying during euglycemia.

CONCLUSION

In health, acceleration of gastric emptying by insulin-induced hypoglycemia is dependent on the degree of hypoglycemia and baseline rate of emptying.

Effect of the Natural Sweetener Xylitol on Gut Hormone Secretion and Gastric Emptying in Humans: A Pilot Dose-Ranging Study

Sugar consumption is associated with a whole range of negative health effects and should be reduced and the natural sweetener xylitol might be helpful in achieving this goal. The present study was conducted as a randomized, placebo-controlled, double-blind, cross-over trial. Twelve healthy, lean volunteers received intragastric solutions with 7, 17 or 35 g xylitol or tap water on four separate days. We examined effects on: gut hormones, glucose, insulin, glucagon, uric acid, lipid profile, as well as gastric emptying rates, appetite-related sensations and gastrointestinal symptoms. We found: (i) a dose-dependent stimulation of cholecystokinin (CCK), active glucagon-like peptide-1 (aGLP-1), peptide tyrosine tyrosine (PYY)-release, and decelerated gastric emptying rates, (ii) a dose-dependent increase in blood glucose and insulin, (iii) no effect on motilin, glucagon, or glucose-dependent insulinotropic peptide (GIP)-release, (iv) no effect on blood lipids, but a rise in uric acid, and (v) increased bowel sounds as only side effects. In conclusion, low doses of xylitol stimulate the secretion of gut hormones and induce a deceleration in gastric emptying rates. There is no effect on blood lipids and only little effect on plasma glucose and insulin. This combination of properties (low-glycemic sweetener which stimulates satiation hormone release) makes xylitol an attractive candidate for sugar replacement.

The Postprandial Glycaemic and Hormonal Responses Following the Ingestion of a Novel, Ready-to-Drink Shot Containing a Low Dose of Whey Protein in Centrally Obese and Lean Adult Males: A Randomised Controlled Trial

PURPOSE

Elevated postprandial glycaemia [PPG] increases the risk of cardiometabolic complications in insulin-resistant, centrally obese individuals. Therefore, strategies that improve PPG are of importance for this population. Consuming large doses of whey protein [WP] before meals reduces PPG by delaying gastric emptying and stimulating the secretion of the incretin peptides, glucose-dependent insulinotropic polypeptide [GIP] and glucagon-like peptide 1 [GLP-1]. It is unclear if these effects are observed after smaller amounts of WP and what impact central adiposity has on these gastrointestinal processes.

METHODS

In a randomised-crossover design, 12 lean and 12 centrally obese adult males performed two 240 min mixed-meal tests, ~5-10 d apart. After an overnight fast, participants consumed a novel, ready-to-drink WP shot (15 g) or volume-matched water (100 ml; PLA) 10 min before a mixed-nutrient meal. Gastric emptying was estimated by oral acetaminophen absorbance. Interval blood samples were collected to measure glucose, insulin, GIP, GLP-1, and acetaminophen.

RESULTS

WP reduced PPG area under the curve [AUC_0-60] by 13 and 18.2% in the centrally obese and lean cohorts, respectively (both p <0.001). In both groups, the reduction in PPG was accompanied by a two-three-fold increase in GLP-1 and delayed gastric emptying. Despite similar GLP-1 responses during PLA, GLP-1 secretion during the WP trial was ~27% lower in centrally obese individuals compared to lean (p = 0.001). In lean participants, WP increased the GLP-1_ACTIVE/TOTAL ratio comparative to PLA (p = 0.004), indicative of reduced GLP-1 degradation. Conversely, no treatment effects for GLP-1_ACTIVE/TOTAL were seen in obese subjects.

CONCLUSION

Pre-meal ingestion of a novel, ready-to-drink WP shot containing just 15 g of dietary protein reduced PPG in lean and centrally obese males. However, an attenuated GLP-1 response to mealtime WP and increased incretin degradation might impact the efficacy of nutritional strategies utilising the actions of GLP-1 to regulate PPG in centrally obese populations. Whether these defects are caused by an individual's insulin resistance, their obese state, or other obesity-related ailments needs further investigation.

CLINICAL TRIAL REGISTRATION

ISRCTN.com, identifier [ISRCTN95281775]. https://www.isrctn.com/.

Prucalopride in diabetic and connective tissue disease-related gastroparesis: Randomized placebo-controlled crossover pilot trial

BACKGROUND

Gastroparesis, defined by delayed gastric emptying in the absence of mechanical outlet obstruction, is a frequent neuropathic complication of diabetes mellitus, and effective treatments are lacking. Prucalopride is a pan-gut prokinetic with selective agonist effects on serotonin 5-HT4 receptors in the gut. This study aimed to assess the effect of prucalopride 4 mg daily on Gastroparesis Cardinal Symptom Index (GCSI), meal-related symptom score (MRSS), and gastric emptying rate in diabetic or connective tissue disease (CTD)-related gastroparesis patients.

METHODS

This was a double-blind crossover trial of four-week treatment periods with prucalopride or placebo divided by two weeks of washout. GSCI, MRSS, gastric emptying scintigraphy, PAGI-SYM, and PAGI-QoL were assessed at baseline and the end of each treatment period. Daily bowel movement (BM) frequency and gastrointestinal symptoms were recorded in each period.

KEY RESULTS

Fifteen gastroparesis patients (13 diabetic, 2 CTD) were enrolled. GCSI scores were lower than baseline but not different between treatment arms. MRSS scores over time or cumulative score were not significantly different between groups. Gastric emptying was more rapid in the prucalopride treatment period, with mean four-hour meal retention of 22 ± 6% in PRU period vs 40 ± 9% in the placebo period (P = 0.05). Weekly BM frequency was significantly higher in prucalopride than placebo periods (10.5 ± 1.8 vs 7.5 ± 0.8, P < 0.0001). Perception of weight loss was higher in patients on prucalopride. Analysis of diabetic gastroparesis (n = 13) population did not change the conclusions.

CONCLUSION AND INFERENCE

Prucalopride at 4 mg accelerates gastric emptying and bowel movement frequency but does not appear to ameliorate gastroparesis or meal-related symptoms in this study.

Gut-Based Strategies to Reduce Postprandial Glycaemia in Type 2 Diabetes

Postprandial glycemic control is an important target for optimal type 2 diabetes management, but is often difficult to achieve. The gastrointestinal tract plays a major role in modulating postprandial glycaemia in both health and diabetes. The various strategies that have been proposed to modulate gastrointestinal function, particularly by slowing gastric emptying and/or stimulating incretin hormone GLP-1, are summarized in this review.

The role of autonomic pathways in peripheral apelin-induced gastrointestinal dysmotility: involvement of the circumventricular organs

NEW FINDINGS

What is the central question of this study? Are central autonomic pathways and circumventricular organs involved in apelin-induced inhibition of gut motility? What is the main finding and its importance? Peripherally administered apelin-13 inhibits gastric and colonic motor functions through sympathetic and parasympathetic autonomic pathways, which seems to be partly mediated by the apelin receptor in circumventricular organs.

ABSTRACT

Peripheral administration of apelin-13 has been shown to inhibit gastrointestinal (GI) motility, but the relevant mechanisms are incompletely understood. This study aimed to investigate (i) whether the apelin receptor (APJ) is expressed in circumventricular structures involved in autonomic functions, (ii) whether they are activated by peripherally administered apelin, (iii) the role of autonomic pathways in peripheral exogenous apelin-induced GI dysmotility, and (iv) the changes in apelin levels in the extracellular environment of the brain following its peripheral application. Ninety minutes after apelin-13 administration (300 μg kg^-1 , i.p.), gastric emptying (GE) and colon transit (CT) were measured in rats that underwent parasympathectomy and/or sympathectomy. Plasma and cerebrospinal fluid (CSF) samples were also collected from another group of rats that received apelin-13 or vehicle injection. The immunoreactivities for APJ and c-Fos in circumventricular organs (CVOs) were evaluated by immunohistochemistry. Compared with vehicle-treated rats, GE and CT were inhibited significantly by apelin-13 treatment, and were completely restored in animals that underwent the combination of parasympathectomy and sympathectomy and sympathectomy alone, respectively. Apelin concentrations were elevated in both plasma and CSF following peripheral administration of apelin-13. APJ expression was detected in area postrema (AP), subfornical organ and organum vasculosum of lamina terminalis, and c-Fos expression was observed in response to apelin injection. Apelin-induced c-Fos expression in AP was partially attenuated by pretreatment with the cholecystokinin-1 receptor antagonist lorglumide, whereas it was completely abolished in vagotomized rats. The present data suggest that APJ in CVOs could indirectly contribute to the inhibitory action of peripheral apelin on GI motor functions.

Sleeve Gastrectomy as a Novel Procedure for Gastroparesis

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has recently been considered for the surgical management of refractory gastroparesis. Our study aims to determine the efficacy of LSG as a new treatment modality for gastroparesis.

METHODS

A multi-surgeon single institution retrospective chart review of patients who underwent LSG for refractory gastroparesis from September 2016-December 2017. Pre- and postoperative Patient Assessment of Upper Gastrointestinal Disorders-Symptoms Severity Index and/or Gastroparesis Cardinal Symptom Index (GCSI) questionnaires were reviewed. A telephone survey was conducted. Statistical analysis consisted of two-sample t test and utilized SAS v9.4. A P-value <.05 was considered significant.

RESULTS

There were 10 patients included and 80% were women with an average age of 43 years (24-63). Mean Body Mass Index was 24.5 (16.8-39.6), and median gastric emptying at 4 hours was 50% (30-85). Etiology of gastroparesis was 50% idiopathic, 40% diabetic, and 10% postsurgical. 80% of patients had previously undergone gastric electrical stimulator implantation, 20% pyloric botox injections, and 1 patient jejunostomy tube placement. One patient required conversion from laparoscopic to open secondary to adhesions. Median length of stay was 5 days (2-13), and median follow-up was 13.3 months. 90% of patients were tolerating a regular diet at longest follow-up with significant improvement in self-reported symptoms. GCSI scores were 33.6 preoperatively and 14.9 postoperatively (P = .01).

DISCUSSION

Our study adds to the literature examining the role of LSG in the treatment of gastroparesis. LSG has favorable outcomes at short-term follow-up for patients with refractory gastroparesis.

Ultrasound assessment of gastric emptying time after intake of clear fluids in children scheduled for general anesthesia-A prospective observational study

BACKGROUND

While many clinics have changed their local regimen toward a more liberal policy regarding clear fluid fasting for general anesthesia, there is a lack of studies evaluating gastric emptying time in a clinical setting.

AIMS

Based on this and before implementation of a more liberal preoperative clear fluid fasting policy for children, we studied gastric emptying time of clear fluids in children and hypothesized that the mean gastric emptying time would be 1 hour.

METHODS

Between March and December 2019, children scheduled for general anesthesia at our University Children's Hospital were enrolled in this prospective observational study. After overnight fasting, gastric emptying was examined by sonographic measurements of the gastric antral area before and 5, 15, 30, 45, and 60 minutes after intake of water or fruit juice.

RESULTS

Twenty-six children were enrolled in this study, and 24 aged 11 (range 4-17) years were included for statistical analysis. The median ingested fluid volume was 4.7 (range 1.8-11.8) mL kg^-1 . The gastric antral area of the children initially increased and subsequently decreased after intake of clear fluids and correlated significantly with fasting time (r = -0.55, P < .0001). After 1 hour, the gastric antral area had returned to the baseline level in 20 children but not in four children with a fluid intake >5 mL kg^-1 . There was no difference in the gastric antral area between water and fruit juice. Using a linear regression model, the calculated mean gastric emptying time of clear fluids was 52 minutes.

CONCLUSION

This study showed that the gastric emptying time of children after intake up to 5 mL kg^-1 clear fluids was <1 hour in a clinical setting. These results support the more liberal fasting regimen favoring a 1-hour fasting time and suggest 5 mL kg^-1 as an upper limit for clear fluids (eg, water, sugared water or tea or diluted fruit juice) from 2 hours to 1 hour before induction of anesthesia in children.

Colonic motility in patients with type 1 diabetes and gastrointestinal symptoms

BACKGROUND

Gastrointestinal (GI) symptoms are common in patients with diabetes mellitus (DM). The electromagnetic 3D-Transit system allows assessment of regional transit times and motility patterns throughout the GI tract. We aimed to compare GI transit times and detailed motility patterns of the colon in patients with DM and GI symptoms to those of healthy controls (HC). We further aimed to determine whether any abnormalities in motility were reversible by cholinergic stimulation.

METHODS

We compared 18 patients with DM with 20 HC by means of the 3D-Transit system. Patients were studied before and during oral administration of 60 mg pyridostigmine.

KEY RESULTS

Compared to HC, patients had prolonged gastric emptying (DM: 3.3 hours (interquartile range (IQR) 2.6-4.6); HC: 2.3 hours (IQR 1.7-2.7) (P < .01)), colonic transit time (DM: 52.6 hours (IQR 23.3-83.0); HC: 22.4 hours (IQR 18.9-43.6) (P = .02)), and whole gut transit time (DM: 69.4 hours (IQR 32.9-103.6); HC: 30.3 hours (IQR 25.2-49.9) (P < .01)). In addition, compared to HC, patients had prolonged transit time in the ascending colon (DM: 20.5 hours (IQR 11.0-44.0); HC: 8.0 hours (IQR 3.8-21.0) (P < .05)) and more slow retrograde movements in the colon (DM: 2 movements (IQR 1-4); HC: 1 movement (IQR 0-1) (P = .01)). In patients, pyridostigmine increased the number of bowel movements (P < .01) and reduced small intestine transit times (P < .05).

CONCLUSIONS

Patients with DM and GI symptoms have longer than normal GI transit times. This is only partly reversible by pyridostigmine. The increased number of retrograde colonic movements in patients could potentially explain the abnormally long transit time in proximal colon.

A transformational change in scintigraphic gastroesophageal reflux studies: A comparison with historic techniques

BACKGROUND

The inclusion of scintigraphy in the diagnostic algorithm for gastroesophageal reflux is controversial due to variability in methodology and reporting. A novel scintigraphic reflux study has been developed and validated against the current standards for the diagnosis of gastroesophageal reflux disease (GORD).

OBJECTIVE

To compare a new scintigraphic reflux test against historic techniques and standardised diagnostic reference tests for gastroesophageal reflux disease.

METHODS

Paired scintigraphic studies were conducted in seventeen patients. All patients underwent at least one other standardised diagnostic reflux test such as 24- hour oesophageal impedance/ pH, and oesophageal manometry, barium swallow, gastroscopy or the Peptest. Patients inadvertently presented at sites B for scintigraphic reflux testing rather than at Site A which was part of an approved study. The findings from sites B did not correlate with clinical symptoms and other diagnostic reference tests from GORD. These studies were then repeated at Site A with approval from the patients. A second reflux study was performed at site A, utilising a novel technique with the capability of assessing oesophageal and extra-oesophageal disease.

RESULTS

The Site A technique shows good concordance with the reference diagnostic tests with an accuracy of 82.4% and kappa of 0.64 (SE: 0.16, p = 0.00). Site B had an overall accuracy of 47.1% and kappa of 0.066 (SE: 0.068, p = 0.45).

CONCLUSION

The Site A technique shows higher accuracy than either site B or the historic reflux techniques. It has characteristics that make it an effective screening tool for assessment of local oesophageal disease and its extraoesophageal manifestations.

Gastrointestinal Mechanisms Underlying the Cardiovascular Effect of Metformin

Metformin, the most widely prescribed drug therapy for type 2 diabetes, has pleiotropic benefits, in addition to its capacity to lower elevated blood glucose levels, including mitigation of cardiovascular risk. The mechanisms underlying the latter remain unclear. Mechanistic studies have, hitherto, focused on the direct effects of metformin on the heart and vasculature. It is now appreciated that effects in the gastrointestinal tract are important to glucose-lowering by metformin. Gastrointestinal actions of metformin also have major implications for cardiovascular function. This review summarizes the gastrointestinal mechanisms underlying the action of metformin and their potential relevance to cardiovascular benefits.

Processing Apples to Puree or Juice Speeds Gastric Emptying and Reduces Postprandial Intestinal Volumes and Satiety in Healthy Adults

BACKGROUND

Whole apples produce greater satiety than processed apples, but the underlying mechanisms remain unclear.

OBJECTIVE

Our aim was to assess the intragastric processing of apple preparations and the associated small and large bowel contents using MRI.

METHODS

An open label, 3-way crossover, randomized, controlled trial. Eighteen healthy adults (mean ± SD age, 25 ± 4 y; BMI, 22.7 ± 3.5 kg/m2) underwent serial MRI scans on 3 occasions separated by 7 d, after consumption of isocaloric (178 kcal) portions of either whole apples, apple puree, or apple juice. Gastric emptying, small bowel water content (SBWC; primary endpoint), were measured at baseline and at 45 min intervals (0-270 min) postmeal ingestion. Fullness and satiety were also assessed at each time point. Treatment effects between groups were analyzed using ANOVA.

RESULTS

Gastric emptying half-time (GE t50) was greater (P < 0.0001) after participants consumed whole apple (mean ± SEM), 65 (3.3) min compared with when they consumed apple puree (41 [2.8] min) or apple juice (38 [2.9] min), times that did not differ. Postprandial area under the curve (AUC) (135-270 min) SBWC was also greater for whole apples than puree (P = 0.025) and juice (P = 0.0004) but juice and puree did not differ. AUC for fullness and satiety (0-270 min) postingestion was also greater (P = 0.002 and 0.004, respectively) for whole apple compared with juice but juice and puree did not differ.

CONCLUSIONS

Gastric emptying is slower after whole apple consumption causing a greater sensation of fullness and satiety than puree or juice in healthy adults. Whole apples increased small bowel and colonic contents during the later phase of the study which may be relevant for subsequent food consumption.This study was registered at clinicaltrials.gov as NCT03714464.

Impact of gastric per-oral endoscopic myotomy on static and dynamic pyloric function in gastroparesis patients

BACKGROUND

Functional Lumen Imaging Probe (EndoFLIP) tests typically measure static pyloric parameters, but the pylorus exhibits phasic variations on manometry. Dynamic changes in pyloric function have not been quantified using EndoFLIP, and the impact of Gastric Per-Oral Endoscopic Myotomy (G-POEM) on static and dynamic pyloric activity in gastroparesis is unknown.

METHODS

EndoFLIP balloon inflation to 30, 40, and 50 mL was performed to measure mean, maximum, and minimum values and variability in pyloric diameter and distensibility before and after G-POEM in 20 patients with refractory gastroparesis. The impact of phasic contractions on these pyloric measures was compared.

KEY RESULTS

G-POEM increased mean (P < .0001) and maximum (P = .0002) pyloric diameters and mean (P = .02) and maximum (P = .02) pyloric distensibility on 50 mL EndoFLIP inflation but not intraballoon pressures or minimum diameters or distensibility. Temporal variability of pyloric diameter (P = .02) and distensibility (P = .02) also increased after G-POEM. Phasic coupled contractions propagating from the antrum through the pylorus were observed in 37.5% of recordings; other phasic activity including isolated pyloric contractions were seen in 23.3%. Variability of pyloric diameter and distensibility tended to be higher during recordings with phasic activity. Some pyloric responses to G-POEM were influenced by age, gastroparesis etiology, gastric emptying, and prior botulinum toxin injection.

CONCLUSIONS & INFERENCES

Pyloric activity exhibits dynamic changes on EndoFLIP testing in gastroparesis. G-POEM increases maximal but not minimal diameter and distensibility with increased variations, suggesting this therapy enhances pyloric opening but may not impair pyloric closure. Phasic pyloric contractions contribute to variations in pyloric activity.

L-Glutamine and Physical Exercise Prevent Intestinal Inflammation and Oxidative Stress Without Improving Gastric Dysmotility in Rats with Ulcerative Colitis

The aim of this study was to evaluate the effects of glutamine supplementation or exercise on gastric emptying and intestinal inflammation in rats with ulcerative colitis (UC). Strength exercise consisted of jump training 4 × 10 repetitions/5 days a week/8 weeks with progressive overload. Endurance exercise consisted of swimming without overload for a period of 1 h a day/5 days a week/8 weeks. Another group (sedentary) of animals was supplemented with L-glutamine (1 g/kg of body weight) orally for 8 weeks before induction of UC. Colitis was induced by intra-colonic administration of 1 mL of 4% acetic acid. We assessed gastric emptying, macroscopic and microscopic scoring, oxidative stress markers, and IL-1β, IL-6, and (TNF-α) levels. The UC significantly increased (p < 0.05) the gastric emptying compared with the saline control group. We observed a significantly decrease (p < 0.05) in body weight gain in UC rats compared with the control groups. Both exercise interventions and L-glutamine supplementation significantly prevented (p < 0.05) weight loss compared with the UC group. Strength and endurance exercises significantly prevented (p < 0.05) the increase of microscopic scores and oxidative stress (p < 0.05). L-glutamine supplementation in UC rats prevented hemorrhagic damage and improved oxidative stress markers (p < 0.05). Strength and endurance exercises and glutamine decreased the concentrations of inflammatory cytokines IL-1β, IL-6, and TNF-α compared with the UC group (p < 0.05). Strength and endurance exercises and L-glutamine supplementation prevented intestinal inflammation and improved cytokines and oxidative stress levels without altering gastric dysmotility in rats with UC.

Whey Protein Drink Ingestion before Breakfast Suppressed Energy Intake at Breakfast and Lunch, but Not during Dinner, and Was Less Suppressed in Healthy Older than Younger Men

Ageing is associated with changes in feeding behavior. We have reported that there is suppression of energy intake three hours after whey protein drink ingestion in young, but not older, men. This study aimed to determine these effects over a time period of 9 h. Fifteen younger (27 ± 1 years, 25.8 ± 0.7 kg/m²) and 15 older (75 ± 2 years, 26.6 ± 0.8 kg/m²) healthy men were studied on three occasions on which they received, in a randomized order, a 30 g/120 kcal, 70 g/280 kcal whey-protein, or control (~2 kcal) drink. Ad-libitum energy intake (sum of breakfast, lunch, and dinner) was suppressed in a protein load responsive fashion (P = 0.001). Suppression was minimal at breakfast, substantial at lunch (~-16%, P = 0.001), no longer present by dinner, and was less in older than younger men (-3 ± 4% vs. -8 ± 4%, P = 0.027). Cumulative protein intake was increased in the younger and older men (+20% and +42%, P < 0.001). Visual analogue scale ratings of fullness were higher and desire to eat and prospective food consumption were lower after protein vs. control, and these effects were smaller in older vs. younger men (interaction effect P < 0.05). These findings support the use of whey-protein drink supplements in older people who aim to increase their protein intake without decreasing their overall energy intake.

Oral D/L-3-Hydroxybutyrate Stimulates Cholecystokinin and Insulin Secretion and Slows Gastric Emptying in Healthy Males

BACKGROUND

D-3-hydroxybutyrate (D-3-OHB) is a ketone body that serves as an alternative nutritional fuel but also as an important signaling metabolite. Oral ketone supplements containing D/L-3-OHB are becoming a popular approach to achieve ketosis.

AIM

To explore the gut-derived effects of ketone supplements.

METHODS

Eight healthy lean male volunteers were investigated on 2 separate occasions:An acetaminophen test was performed to evaluate gastric emptying and blood samples were obtained consecutively throughout the study period.

RESULTS

We show that oral consumption of D/L-3-OHB stimulates cholecystokinin release (P = 0.02), elevates insulin (P = 0.03) and C-peptide (P < 0.001) concentrations, and slows gastric emptying (P = 0.01) compared with matched intravenous D/L-3-OHB administration. Measures of appetite and plasma concentrations of glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) were unaffected by interventions.

CONCLUSION

Our findings show that D/L-3-OHB exert incretin effects and indicate luminal sensing in the gut endothelium. This adds to our understanding of ketones as signaling metabolites and displays the important difference between physiological ketosis and oral ketone supplements.

Effects of Moxibustion on Stress-Induced Delayed Gastric Emptying via Somatoautonomic Reflex in Rats

Objective: Moxibustion (MOX) is used to treat a wide variety of disorders, including those with gastric symptoms. However, the exact mechanisms underlying the beneficial effects of MOX are unknown. The purpose of this study was to investigate if application of indirect MOX (iMOX) to ST 36 reduces restraint stress (RS)-induced alteration in gastric responses of conscious rats, and if a somatoautonomic reflex mediates gastric emptying (GE). Materials and Methods: One group of rats was fed solid food after 24 hours of fasting. Immediately after food ingestion. These rats were subjected to RS. Ninety minutes after feeding, the rats were euthanized, and their gastric contents were removed to calculate GE. iMOX had been performed at ST 36 bilaterally throughout the stress loading. To investigate if vagal-nerve activity was involved in mediating the stress-induced alterations of GE by iMOX, atropine was intraperitoneally administered to other rats just before initiating RS; bilateral truncal vagotomy had been performed on day 14 before GE measurement. Results: RS delayed GE significantly (42.9 ± 5.8%)in stressed rats, compared to nonstressed rats (68.7 ± 1.8%). iMOX at ST 36 reduced stress-induced inhibition of GE significantly (67.1 ± 2.4%). MOX-mediated reduction of GE disappeared upon atropine injection and vagotomy. Conclusions: RS-induced delayed GE may be ameliorated by iMOX at ST 36. Somatoautonomic, reflex-induced vagal-nerve activity helps mediate the stimulatory effects of iMOX on RS-induced delayed GE. As a complementary and alternative medicine, iMOX may also be advantageous for patients with gastric disorders, such as functional dyspepsia.

Inhibition of GSK-3β restores delayed gastric emptying in obesity-induced diabetic female mice

Diabetic gastroparesis (DG) is a clinical syndrome characterized by delayed gastric emptying (DGE). Loss of nuclear factor erythroid 2-related factor 2 (Nrf2) is associated with reduced neuronal nitric oxide synthase-α (nNOSα)-mediated gastric motility and DGE. Previous studies have shown that nuclear exclusion and inactivation of Nrf2 is partly regulated by glycogen synthase kinase 3β (GSK-3β). In the current study, the molecular signaling of GSK-3β-mediated Nrf2 activation and its mechanistic role on DG were investigated in high-fat diet (HFD)-induced obese/Type 2 diabetes (T2D) female mice. Adult female C57BL/6J mice were fed with HFD or normal diet (ND) with or without GSK-3β inhibitor (SB 216763, 10 mg/kg body wt ip) start from the 14th wk and continued feeding mice for an additional 3-wk time period. Our results show that treatment with GSK-3β inhibitor SB attenuated DGE in obese/T2D mice. Treatment with SB restored impaired gastric 1) Nrf2 and phase II antioxidant enzymes through PI3K/ERK/AKT-mediated pathway, 2) tetrahydrobiopterin (BH₄, cofactor of nNOS) biosynthesis enzyme dihydrofolate reductase, and 3) nNOSα dimerization in obese/T2 diabetic female mice. SB treatment normalized caspase 3 activity and downstream GSK-3β signaling in the gastric tissues of the obese/T2 diabetic female mice. In addition, GSK-3β inhibitor restored impaired nitrergic relaxation in hyperglycemic conditions. Finally, SB treatment reduced GSK3 marker, pTau in adult primary enteric neuronal cells. These findings emphasize the importance of GSK-3β on regulating gastric Nrf2 and nitrergic mediated gastric emptying in obese/diabetic rodents.NEW & NOTEWORTHY Inhibition of glycogen synthase kinase 3β (GSK-3β) with SB 216763 attenuates delayed gastric emptying through gastric nuclear factor erythroid 2-related factor 2 (Nrf2)-phase II enzymes in high-fat diet-fed female mice. SB 216763 restored impaired gastric PI3K/AKT/ β-catenin/caspase 3 expression. Inhibition of GSK-3β normalized gastric dihydrofolate reductase, neuronal nitric oxide synthase-α expression, dimerization and nitrergic relaxation. SB 216763 normalized both serum estrogen and nitrate levels in female obese/Type 2 diabetes mice. SB 216763 reduced downstream signaling of GSK-3β in enteric neuronal cells in vitro.

Bile acid composition regulates GPR119-dependent intestinal lipid sensing and food intake regulation in mice

OBJECTIVES

Lipid mediators in the GI tract regulate satiation and satiety. Bile acids (BAs) regulate the absorption and metabolism of dietary lipid in the intestine, but their effects on lipid-regulated satiation and satiety are completely unknown. Investigating this is challenging because introducing excessive BAs or eliminating BAs strongly impacts GI functions. We used a mouse model (Cyp8b1^-/- mice) with normal total BA levels, but alterations in the composition of the BA pool that impact multiple aspects of intestinal lipid metabolism. We tested two hypotheses: BAs affect food intake by (1) regulating production of the bioactive lipid oleoylethanolamide (OEA), which enhances satiety; or (2) regulating the quantity and localisation of hydrolysed fat in small intestine, which controls gastric emptying and satiation.

DESIGN

We evaluated OEA levels, gastric emptying and food intake in wild-type and Cyp8b1^-/- mice. We assessed the role of the fat receptor GPR119 in these effects using Gpr119^-/- mice.

RESULTS

Cyp8b1^-/- mice on a chow diet showed mild hypophagia. Jejunal OEA production was blunted in Cyp8b1^-/- mice, thus these data do not support a role for this pathway in the hypophagia of Cyp8b1^-/- mice. On the other hand, Cyp8b1 deficiency decreased gastric emptying, and this was dependent on dietary fat. GPR119 deficiency normalised the gastric emptying, gut hormone levels, food intake and body weight of Cyp8b1^-/- mice.

CONCLUSION

BAs regulate gastric emptying and satiation by determining fat-dependent GPR119 activity in distal intestine.

Emulsion Droplet Crystallinity Attenuates Short-Term Satiety in Healthy Adult Males: A Randomized, Double-Blinded, Crossover, Acute Meal Study

BACKGROUND

The influence of triacylglycerol (TAG) physical properties on satiety remains poorly understood.

OBJECTIVES

The objective was to investigate if and how TAG digestion and absorption, modulated only by differences in TAG crystallinity, would differentially affect short-term satiety in healthy men.

METHODS

We tempered 500 mL 10% palm stearin oil-in-water emulsions such that the lipid droplets were either undercooled liquid (LE) or partially crystalline solid (SE). Fifteen healthy men (mean ± SD age: 27.5 ± 5.7 y; BMI: 24.1 ± 2.5 kg/m2; fasting TAG: 0.9 ± 0.3 mmol/L) consumed each beverage at two 6-h study visits separated by ≥6 d after an overnight fast, along with 1500 mg acetaminophen suspended in water. The participants characterized the emulsion sensory properties, completed satiety visual analog scale ratings, and had serial blood samples collected for 6-h analysis of plasma peptide YY (PYY), glucagon-like peptide-1 (GLP-1), ghrelin, leptin, glucose-dependent insulinotropic polypeptide (GIP), insulin, and acetaminophen (for assessing gastric emptying). Repeated-measures ANOVAs and 2-tailed paired t tests were used to analyze the changes from baseline and incremental area under the curve (iAUC) values, respectively.

RESULTS

With consumption of LE compared with SE, there was a 358% higher fullness (P = 0.015) and a 103% lower average appetite (P = 0.041) score, along with higher iAUC values for PYY (P = 0.011) and GLP-1 (P = 0.028) (103% and 66% higher, respectively), but not for ghrelin (P = 0.39), based on change from baseline values. Acetaminophen response trended toward significance (P = 0.08) and was 15% higher with LE. SE was rated as 44% thicker (P = 0.034) and 24% creamier (P = 0.05) than LE.

CONCLUSIONS

The suppression of TAG digestion by the presence of partially crystalline lipid droplets blunted the appetite-suppressing effects of an oil-in-water emulsion.This trial was registered at clinicaltrials.gov as NCT03990246.

A Pilot Study Examining the Effects of GLP-1 Receptor Blockade Using Exendin-(9,39) on Gastric Emptying and Caloric Intake in Subjects With and Without Bariatric Surgery

Background: Obesity causes significant morbidity and mortality and continues to be a significant public health concern. Unfortunately, lifestyle modification and pharmacotherapy do not produce durable results. This has led to bariatric surgical procedures playing an increasingly prominent role in the management of medically complicated obesity. Roux-en-Y gastric bypass and sleeve gastrectomy are the most commonly performed bariatric surgeries in North America and produce mechanical restriction with accelerated gastrointestinal transit accompanied by increased postprandial secretion of glucagon-like peptide-1 (GLP-1). GLP-1 is a gastrointestinal hormone that delays gastric emptying and causes satiety and weight loss. This raises the possibility that the postprandial rise in GLP-1 might affect feeding behavior over and above the mechanical restriction produced by bariatric surgery. Methods: We, therefore, sought to determine the effects of GLP-1 receptor blockade using exendin-9,39-a competitive antagonist of the actions of GLP-1 at its receptor-on caloric intake and gastrointestinal transit in subjects after sleeve gastrectomy and after Roux-en-Y gastric bypass compared with weight-matched controls. Results: GLP-1 receptor blockade did not alter caloric intake in people after bariatric surgery. However, caloric intake was decreased in age-, weight- and sex-matched control subjects, and the mechanisms require further study. Conclusions: Given the known effects of GLP-1 on gastric accommodation, future studies should ascertain effects of GLP-1 receptor blockade on gastric accommodation, which might be a useful and novel strategy to decrease caloric intake in humans with an intact upper gastrointestinal tract. The Clinical Trial Resigtration number is NCT02779075.

Curcumin Alleviates the Side Effects of Cisplatin on Gastric Emptying of Mice by Inhibiting the Signal Changes of Acetylcholine and Interstitial Cells of Cajal

Cisplatin is a widely used anticancer drug that has adverse effects on gastrointestinal function. Curcumin is a natural polyphenol extracted from the rhizome of turmeric that has a wide range of biological activities. The present study investigated the effects of cisplatin on gastric emptying in mice and examined whether these can be inhibited by curcumin. We found that pretreatment with curcumin (200 mg/kg/day) for 10-30 days partly inhibited the decreases in gastric emptying rate and body weight induced by cisplatin. Furthermore, cisplatin reduced acetylcholine (ACh) concentration and the messenger RNA (mRNA) level of ACh receptor (AChR) as well as acetylcholinesterase activity in the stomach of mice; caused ultrastructural damage to interstitial cells of Cajal (ICC); and altered the expression of c-kit/stem cell factor and the gap junction protein connexin 43 in ICC. Curcumin pretreatment inhibited the effects of cisplatin on ACh indicators and ICC. These results demonstrate that curcumin can protect against cisplatin-induced gastric emptying disorder and thus has therapeutic potential for alleviating this condition in cancer patients receiving cisplatin chemotherapy.

Acotiamide attenuates central urocortin 2-induced intestinal inflammatory responses, and urocortin 2 treatment reduces TNF-α productions in LPS-stimulated macrophage cell lines

BACKGROUND

To determine whether central and in vitro administration of urocortin 2 (Ucn 2) affected intestinal inflammatory responses in LPS-stimulated rat models and macrophage cell lines and acotiamide modified mucosal inflammation in this model.

METHODS

Rats were divided into four groups. LPS-stimulated group (n = 4); LPS- and urocortin 2-treated group (n = 4); LPS- and acotiamide-treated group (n = 4); and LPS-, urocortin 2-, and acotiamide-treated group (n = 4). CD68-, CCR2-, and corticotropin-releasing hormone receptor type 2 (CRHR2)-positive cells were assessed by immunostaining. Myeloperoxidase (MPO) activity was measured. TNF-α, IL-6, and IL-4 levels were measured by ELISA method. Gastric emptying and small intestinal transit time were determined using Evans blue.

KEY RESULTS

Central administration of Ucn 2 significantly aggravated infiltrations of CD68- and CCR2-positive cells in the intestinal mucosa of LPS-stimulated rat models compared to those in LPS treatment alone. Interestingly, acotiamide treatment significantly reduced the migrations of both CD68- and CCR2-positive cells in the jejunum of central Ucn 2-treated LPS-stimulated rat models. Acotiamide significantly reduced the expression levels of IkB-α phosphorylation in LPS- and MCP-1-stimulated NR8383 cells. Central administration of Ucn 2 significantly delayed gastric emptying. In contrast, Ucn 2 stimulation significantly reduced TNF-α and IL-6 productions in LPS-stimulated NR8383 cells and astressin B reversed the inhibition of TNF-α production in stimulated NR8383 cells. Acotiamide (30 μmol/L) significantly reduced TNF-α and IL-6 productions in LPS- and MCP-1-stimulated NR8383 cells.

CONCLUSIONS AND INFERENCES

Central and in vitro treatments of Ucn 2 affected intestinal inflammatory responses, respectively, and acotiamide improved them.

Gastrointestinal motility evaluation in children with orthostatic intolerance: Mayo Clinic experience

OBJECTIVE

Orthostatic intolerance (OI) and autonomic dysfunction (AD) are common in adolescents and young adults. Patients experience multisystem symptoms including gastrointestinal (GI), postural orthostatic tachycardia syndrome (POTS), orthostatic hypotension (OH), or only symptoms of OI (SOI) without significant findings on 70-degree head-up tilt testing (HUT). We hypothesize that patients with POTS, OH, and SOI show differences in GI symptoms and motility test and that heart rate (HR) changes on HUT predict severity of GI dysmotility.

STUDY DESIGN

From medical records of patients (<18 years) with OI, we collected demographics, presenting symptoms, GI manifestations, and GI motility testing. Data were compared between the 3 groups (POTS, OH, and SOI). We assessed changes in HR on HUT with changes on GI motility evaluation.

RESULTS

Two hundred twenty-nine patients were included (73% females). Abdominal pain (65%), nausea (49%), vomiting (18%), and constipation (24%) were the most common GI symptoms. In patients who had motility evaluation, there were 27% (53/193) with delayed gastric emptying (GE) at 4 hours, 35% (32/92) with delayed colonic transit (CT), 55% (17/31) with reduced gastric accommodation (GA), and 75% (21/28) with dyssynergic defecation (DD). Among 100 POTS, 34 OH, and 95 SOI patients, no significant differences in GI symptoms or motility tests were identified and HR changes on HUT were not associated with changes on motility tests.

CONCLUSION

GI symptoms are frequent in adolescents with OI and are associated with delayed GE, reduced GA, delayed CT, and presence of DD.

Volume and position change of the stomach during gastric accommodation and emptying: A detailed three-dimensional morphological analysis based on MRI

BACKGROUND

The proximal and distal regions of the stomach are thought to have different roles during gastric accommodation and emptying; however, regional changes in gastric structure and function during and after a meal have not been described in detail. This study applied non-invasive imaging to study changes in regional gastric volume and morphology during accommodation and emptying of a liquid nutrient meal.

METHOD

MRI studies were performed on 16 healthy volunteers. Three-dimensional (3D) gastric morphology was reconstructed by validated image processing technology. The 3D models were segmented into seven regions. The relative contribution of each region to gastric accommodation and emptying was assessed. Changes in morphology were documented by tracking movements of four distinct gastric landmarks.

KEY RESULTS

The initial 100 mL liquid nutrient increases distal stomach volume more than that of other gastric regions (∆V7 = 28 ± 6% ∆TGV; P ≤ .05). Subsequent volume is accommodated mainly in the proximal stomach (∆V1 = 42 ± 10% ∆TGV; P ≤ .05). Early-phase emptying occurs from distal stomach with proximal stomach volume remaining stable. Subsequently, distal stomach volume remains stable while proximal stomach volume decreases progressively. During gastric filling, the stomach elongates and expands anteriorly and inferiorly (15.2 ± 7.4 mm and 32.3 ± 8.4 mm, respectively, for the incisural midpoint) with torsion indicated by ~70° difference in the movements of proximal and distal gastric landmarks.

CONCLUSIONS AND INFERENCES

Non-invasive MRI describes volume change and distribution of a liquid meal within proximal and distal stomach during gastric accommodation and emptying. Additionally, novel observations of changes to 3D gastric morphology within the abdomen are documented.

Autonomic function in gastroparesis and chronic unexplained nausea and vomiting: Relationship with etiology, gastric emptying, and symptom severity

BACKGROUND

Autonomic dysfunction can be present in patients with idiopathic and diabetic gastroparesis. The role of autonomic dysfunction relating to gastric emptying and upper gastrointestinal symptoms in patients with gastroparesis and chronic unexplained nausea and vomiting (CUNV) remains unclear. The aim of our study is to evaluate autonomic function in patients with gastroparesis and CUNV with respect to etiology, gastric emptying and symptom severity.

METHODS

We studied 242 patients with chronic gastroparetic symptoms recruited at eight centers. All patients had a gastric emptying scintigraphy within 6 months of the study. Symptom severity was assessed using the gastroparesis cardinal symptom index. Autonomic function testing was performed at baseline enrollment using the ANX 3.0 autonomic monitoring system which measures heart rate variability and respiratory activity measurements.

KEY RESULTS

Low sympathetic response to challenge (Valsalva or standing) was the most common abnormality seen impacting 89% diabetic and 74% idiopathic patients. Diabetics compared to idiopathics, exhibited greater global hypofunction with sympathetic (OR = 4.7, 95% CI 2.2-10.3; P < .001) and parasympathetic (OR = 7.2, 95% CI 3.4-15.0; P < .001) dysfunction. Patients with delayed gastric emptying were more likely to have paradoxic parasympathetic excessive during sympathetic challenge [(Valsalva or standing) 40% vs. 26%, P = .05]. Patients with more severe symptoms exhibited greater parasympathetic dysfunction compared to those with mild-moderate symptoms: resting sympathovagal balance [LFa/RFa 1.8 (1.0-3.1) vs. 1.2 (0.6-2.3), P = .006)] and standing parasympathetic activity [0.4 (0.1-0.8) vs. 0.6 (0.2-1.7); P = .03].

CONCLUSIONS

Autonomic dysfunction was common in patients with gastroparesis and CUNV. Parasympathetic dysfunction was associated with delayed gastric emptying and more severe upper gastrointestinal symptoms. Conversely, sympathetic hypofunction was associated with milder symptoms.

INFERENCES

Gastroparesis and CUNV may be a manifestation of GI autonomic dysfunction or imbalance, such that sympathetic dysfunction occurs early on in the manifestation of chronic upper GI symptoms, while parasympathetic dysfunction results in more severe symptoms and delayed gastric emptying.

Pyloroplasty and the risk of Barrett's esophagus in patients with gastroparesis

Barrett's esophagus (BE), a consequence of gastroesophageal reflux disease (GERD), is a premalignant condition for esophageal adenocarcinoma. Impaired gastric emptying leads to increased gastric volume and therefore more severe reflux. We seek to investigate the association between gastroparesis and BE and the predictors of BE among patients with gastroparesis. This is a retrospective review of patients seen at Cleveland Clinic between 2011 and 2016 who had an upper endoscopy and a gastric emptying study. Demographics, symptoms, medications, endoscopic and histological findings, and therapeutic interventions were abstracted. Risk of BE among gastroparesis group and control group was assessed, and logistic regression analysis was performed to identify predictors of BE among gastroparesis patients. Of the 4,154 patients, 864 (20.8%) had gastroparesis and 3, 290 (79.2%) had normal gastric emptying. The mean age was 51.4 ± 16.4 years, 72% were women and 80% were Caucasians. Among the gastroparesis group, 18 (2.1%) patients had BE compared to 71 (2.2%) cases of BE in the control group, P = 0.89. There were no differences in gender, race, reflux symptoms, or esophageal findings between the two groups. Among gastroparesis group, predictors of developing BE were a history of alcohol use (odds ratio [OR] 6.76; 95% confidence intervals [CI]: 1.65-27.67, P = 0.008), history of pyloroplasty (OR: 8.228; CI: 2.114-32.016, P = 0.002), and hiatal hernia (OR: 8.014; CI: 2.053-31.277, P = 0.003). Though gastroparesis is a known contributing factor for GERD, there was no increased prevalence of BE in gastroparesis. Among patients with gastroparesis, predictors of BE are history of alcohol use, hiatal hernia, and pyloroplasty.

Destructuring and restructuring of foods during gastric digestion

All foods harbor unique length scale-dependent structural features that can influence the release, transport, and utilization of macro- or micronutrients in the human gastrointestinal tract. In this regard, food destructuring and restructuring processes during gastric passage significantly influence downstream nutrient assimilation and feelings of satiety. This review begins with a synopsis of the effects of oral processing on food structure. Then, stomach-centric factors that contribute to the efficacy of gastric digestion are discussed, and exemplified by comparing the intragastric de- and restructuring of a number of common foods. The mechanisms of how intragastric structuring influences gastric emptying and its relationship to human satiety are then discussed. Finally, recently developed, non-destructive instrumental approaches used to quantitively and qualitatively characterize food behavior during gastric destructuring and restructuring are described.

Stomach 'tastes' the food and adjusts its emptying: A neurophysiological hypothesis (Review)

The presence of taste receptors and their secondary messengers in stomach raised the possibility that the stomach might play a role in food 'tasting' and consequently, it might initiate specific adaptations of its secretory and motor function. Furthermore, activated taste receptors release a variety of chemical mediators able to modulate the activity of the enteric nervous system (ENS), and also to influence both secretory and motor functions of the stomach. Based on the physiological fundamental structure of a reflex arch, the stimulation of the gastric taste receptors activates sensory neurons of the gastric wall, continues with motor neurons which initiate the contraction of the local smooth muscle fibers. Beyond this, compounds which act on different taste receptors initiate different responses, stimulatory or inhibitory. These interactions may be translated in the gastric ability to selectively evacuate different nutritive compounds into the duodenum. Consequently, sugars could be favored to the detriment of other compounds.

Interleukin-10 and Zonulin Are Associated With Postoperative Delayed Gastric Emptying in Critically Ill Surgical Pediatric Patients: A Prospective Pilot Study

Background

Impaired gastric emptying (GE) is associated with morbidity in surgical critically ill children. The relationship between inflammation, gut barrier integrity (lipopolysaccharide binding protein [LBP]; zonulin), and GE has not been described in this cohort.

Methods

Children ≥2 years of age and requiring critical care after surgery were enrolled. Preoperative and postoperative levels of serum cytokines, LBP, and zonulin, and GE by the acetaminophen absorption test, were measured, allowing patients to serve as their own controls. Postoperative delayed GE was defined as a decrease in GE by ≥20% compared with preoperative GE. The following were examined : comparison between postoperative andpreoperative values, correlations between fold change (postoperative/preoperative) in study variables, and fold change in study variables between patients with and without postoperative delayed GE.

Results

Twenty patients, median age 14 years (12.25, 18), 12 female, were included. Eight of 20 patients had postoperative delayed GE. Postoperative interleukin‐6 (IL‐6), IL‐8, IL‐10, and LBP were increased, and zonulin was decreased (P‐values < .05). Fold change in IL‐10 and zonulin were inversely correlated (ρ −0.618, P = .004). Patients with postoperative delayed GE had greater fold increase in IL‐10 (P = .0159) and fold decrease in zonulin (P = .0160). Five of 7 (71%) patients with both fold increase in IL‐10 and decrease in zonulin had delayed GE.

Conclusion

Postoperative changes in IL‐10 and zonulin were associated with delayed GE in surgical critically ill children, which might suggest a mechanism to for delayed GE in postoperative inflammation and gut barrier dysregulation after surgery.

Endokinin A/B stimulates rat gastric motility through myogenic NK1 receptors located in the fundus

Endokinin A/B (EKA/B), the common C-terminal decapeptide in endokinins A and B, is a preferred ligand of the NK1 receptor and regulates pain and itch. The study focused on the effects of EKA/B on rat gastric motility in vivo and in vitro. Gastric emptying was measured to evaluate gastric motility in vivo. Intragastric pressure and the contraction of gastric muscle strips were measured to evaluate gastric motility in vitro. Moreover, various neural blocking agents and neurokinin receptor antagonists were applied to explore the mechanisms. TAC4 and TACR1 mRNAs were expressed throughout rat stomach. EKA/B promoted gastric emptying by intraperitoneal injection in vivo. Correspondingly, EKA/B also increased intragastric pressure in vitro. Additionally, EKA/B contracted the gastric muscle strips from the fundus but not from the corpus or antrum. Further studies revealed that the contraction induced by EKA/B on muscle strips from the fundus could be significantly reduced by NK1 receptor antagonist SR140333 but not by NK2 receptor antagonist, NK3 receptor antagonist, or the neural blocking agents used. Our results suggested that EKA/B might stimulate gastric motility mainly through the direct activation of myogenic NK1 receptors located in the fundus.

Ultrasonographic evaluation of gastric emptying after ingesting carbohydrate-rich drink in young children: A randomized crossover study

BACKGROUND

A recent consensus statement in Europe has suggested that the fasting time for clear liquid in children can be shortened to 1 hour before a surgery. However, the study to show that 1-hour fasting time for clear fluids is safe in young children is still lacking. This study aimed to investigate the gastric emptying time for carbohydrate-rich drink and regular 5% glucose solution in children aged 3-7 years.

METHODS

After overnight fasting, individuals were randomly assigned to ingest 5 mL kg^-1 of either carbohydrate-rich drink or 5% glucose solution. One week later, the same subjects were asked to ingest the other one. Ultrasonography was performed to examine the gastric contents. Gastric antral cross-sectional area was measured, and the gastric fluid volume was calculated before and after fluid ingestion within 120 minutes. The primary outcome was the gastric emptying time for both the clear fluids calculated using the antral cross-sectional area and logarithms of gastric fluid volume. The degrees of thirst and hunger of two drinks were evaluated using a visual analogue scale as the secondary outcomes.

RESULTS

Data from 16 individuals were analyzed. In the glucose solution group, the antral cross-sectional area and logarithms of gastric fluid volume returned to baseline at 30 minutes after ingestion. However, in the carbohydrate-rich drink group, the median [interquartile range; range] antral cross-sectional area (3.69 [2.64-5.15; 1.83-8.93] cm² vs 2.41 [2.10-2.96; 1.81-4.37] cm² , P < .001) and mean (95% confidence interval) logarithms of gastric fluid volume (2.54 [2.30-2.79] mL vs 2.12 [1.94-2.30] mL, P = .048) were still higher than at 60 minutes and returned to the baseline values at 90 minutes after ingestion, respectively. The degree of thirst was lower in the glucose solution group than that in the carbohydrate-rich drink group.

CONCLUSIONS

Gastric emptying of carbohydrate-rich drink is slower than that of 5% glucose solution but the residual gastric fluid volume is low one hour after ingestion of 5 mL kg^-1 of either fluid.

Exenatide once weekly slows gastric emptying of solids and liquids in healthy, overweight people at steady-state concentrations

AIMS

To evaluate the effects of 8 weeks' administration of exenatide (EXE) once weekly on gastric emptying of solids and liquids (using the "gold standard" technique, scintigraphy), glucose absorption and postprandial glycaemia in healthy people.

MATERIAL AND METHODS

A total of 32 healthy participants were randomized to receive either EXE once weekly (2 mg/wk subcutaneously; six men, 10 women, mean age 59.9 ± 0.9 years, mean body mass index [BMI] 29.6 ± 0.6 kg/m² ) or matching placebo (PBO; six men, 10 women, mean age 60.6 ± 1.2 years, mean BMI 29.5 ± 1.0 kg/m² ) for 8 weeks. Gastric emptying, nausea (visual analogue scale), and plasma glucose, insulin, C-peptide and glucagon were measured for 120 min after a solid/liquid meal, comprising 100 g ground beef (radiolabelled with 20 MBq ^99m Tc-sulphur colloid) and 150 mL 10% glucose (radiolabelled with 7 MBq ⁶⁷ Ga-EDTA), and containing 5 g 3-O-methyl-glucose (3-OMG) as a marker of glucose absorption, at baseline and after 8 weeks' treatment.

RESULTS

The study treatments were well tolerated. Scores for nausea were consistently low, with no difference between the EXE once weekly and PBO groups. EXE once weekly slowed gastric emptying of solids (area under the curve [AUC]_0-120min : P < 0.05) and liquids (AUC_0-120min : P = 0.01) substantially, and attenuated glucose absorption (3-OMG incremental AUC [iAUC]_0-30min : P = 0.001) and the postprandial rise in plasma glucose (iAUC_0-30min : P = 0.008). Plasma glucagon at 2 h was reduced by EXE once weekly (P = 0.001). The magnitude of the reduction in plasma glucose at t = 30 min from baseline to 8 weeks with EXE once weekly was related inversely to the 50% emptying time of the glucose drink (r = -0.55, P = 0.03).

CONCLUSIONS

In healthy participants, 8 weeks' administration of the "long-acting" glucagon-like peptide-1 receptor agonist EXE, slowed gastric emptying of solids and liquids substantially, with consequent reductions in glucose absorption and postprandial glycaemia.

Hypoganglionosis in the gastric antrum causes delayed gastric emptying

BACKGROUND

Enteric nervous system (ENS) abnormalities have been implicated in delayed gastric emptying but studies exploring potential treatment options are limited by the lack of an experimental animal model. We examined the ENS abnormalities in the mouse stomach associated with aging, developed a novel model of gastroparesis, and established a new approach to measure gastric emptying.

METHODS

A modified gastric emptying assay was developed, validated in nNOS ^-/- mice, and tested in mice at multiple ages. Age-related changes in ENS structure were analyzed by immunohistochemistry. Gastric aganglionosis was generated in Wnt1-iDTR mice using focal administration of diphtheria toxin (DT) into the anterior antral wall.

KEY RESULTS

Older mice (>5 months) exhibit hypoganglionosis in the gastric antrum and a decreased proportion of nNOS neurons as compared to younger mice (age 5-7 weeks). This was associated with a significant age-dependent decrease in liquid and solid gastric emptying. A novel model of gastric antrum hypoganglionosis was established using neural crest-specific expression of diphtheria toxin receptor. In this model, a significant reduction in liquid and solid gastric emptying is observed.

CONCLUSIONS & INFERENCES

Older mice exhibit delayed gastric emptying associated with hypoganglionosis and a reduction in nNOS-expressing neurons in the antrum. The causal relationship between antral hypoganglionosis and delayed gastric emptying was verified using a novel experimental model of ENS ablation. This study provides new information regarding the pathogenesis of delayed gastric emptying and provides a robust model system to study this disease and develop novel treatments.

Suppression of Oral Sweet Sensations during Consumption of Sweet Food in Humans: Effects on Gastric Emptying Rate, Glycemic Response, Appetite, Food Satisfaction and Desire for Basic Tastes

Suppression of oral sweet sensation (OSS) acutely reduces intake of sweet-tasting food due to lower liking. However, little is known about other physiological responses during both the prandial and postprandial phase. Here, we explored the effects of Gymnema sylvestre (GS)-based suppression of OSS of several types of sweet-tasting food (muffin, sweet yogurt, banana) on gastric emptying, blood glucose (BG), plasma insulin (PI), appetite indices (hunger, fullness and prospective consumption), satisfaction and desire for tastes. Fifteen healthy subjects (22 ± 3 years, 9 women) took part in the study. Subjects rinsed their mouth with either GS solution or distilled water before eating the sweet-tasting food. Subjects felt decreased sweet taste intensity and reduced taste liking associated with GS rinsing after consuming each food, compared with rinsing with distilled water (p < 0.05). Gastric emptying, BG, PI and appetite indices during and after the prandial phase did not significantly change with GS rinsing compared to rinsing with distilled water (p > 0.05). Higher desire for sweet taste as well as lower satisfaction (p < 0.05) in the postprandial phase were observed with GS rinsing. These results suggest that the suppression of OSS does not affect gastric emptying, glycemic response and appetite during and after consumption of sweet-tasting food.

Effects of Age on Acute Appetite-Related Responses to Whey-Protein Drinks, Including Energy Intake, Gastric Emptying, Blood Glucose, and Plasma Gut Hormone Concentrations-A Randomized Controlled Trial

Protein-rich supplements are used commonly to increase energy intake in undernourished older people. This study aimed to establish age effects on energy intake, appetite, gastric emptying, blood glucose, and gut hormones in response to protein-rich drinks. In a randomized double-blind, order, 13 older men (age: 75 ± 2 yrs, body mass index (BMI): 26 ± 1 kg/m²) and 13 younger (23 ± 1 yrs, 24 ± 1 kg/m²) men consumed (i) a control drink (~2 kcal) or drinks (450 mL) containing protein/fat/carbohydrate: (ii) 70 g/0 g/0 g (280 kcal/'P_280'), (iii) 14 g/12.4 g/28 g (280 kcal/'M_280'), (iv) 70 g/12.4 g/28 g (504 kcal/'M_504'), on four separate days. Appetite (visual analog scales), gastric emptying (3D ultrasonography), blood glucose, plasma insulin, ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1) concentrations (0-180 min), and ad-libitum energy intake (180-210 min) were determined. Older men, compared to younger men, had higher fasting glucose and CCK concentrations and lower fasting GLP-1 concentrations (all p < 0.05). Energy intake by P₂₈₀ compared to control was less suppressed in older men (increase: 49 ± 42 kcal) than it was in younger men (suppression: 100 ± 54 kcal, p = 0.038). After the caloric drinks, the suppression of hunger and the desire to eat, and the stimulation of fullness was less (p < 0.05), and the stimulation of plasma GLP-1 was higher (p < 0.05) in older men compared to younger men. Gastric emptying, glucose, insulin, ghrelin, and CCK responses were similar between age groups. In conclusion, ageing reduces the responses of caloric drinks on hunger, the desire to eat, fullness, and energy intake, and protein-rich nutrition supplements may be an effective strategy to increase energy intake in undernourished older people.

Effects of sequential treatment with lixisenatide, insulin glargine, or their combination on meal-related glycaemic excursions, insulin and glucagon secretion, and gastric emptying in patients with type 2 diabetes

AIM

To examine the glucose-lowering mechanisms of the glucagon-like peptide-1 receptor agonist lixisenatide after two subsequent meals and in combination with basal insulin.

MATERIALS AND METHODS

Twenty-eight metformin-treated patients with type 2 diabetes were randomly assigned to treatment sequences with either lixisenatide or insulin glargine alone for 4 weeks, and a combination of both treatments for 4 weeks. Metabolic examinations were performed before and after each treatment period following breakfast and a late lunch 8 hours later.

RESULTS

Lixisenatide mainly reduced postprandial glycaemia, while insulin glargine mainly reduced fasting glucose after breakfast (P < 0.05). This was partially preserved after a late lunch (P < 0.05). After breakfast, lixisenatide reduced insulin secretion and glucagon levels significantly. These effects were lost after a late lunch. Insulin glargine did not significantly reduce glucagon or insulin secretion. Gastric emptying was slowed by lixisenatide, but not by insulin glargine after breakfast. After the late lunch, lixisenatide slightly accelerated gastric emptying.

CONCLUSIONS

Lixisenatide decelerates gastric emptying after breakfast, thereby reducing glycaemic excursions, insulin secretion and glucagon levels. The glycaemic reduction persists until after a late lunch, despite accelerated gastric emptying. The combination with insulin glargine enhances the glucose-lowering effect because of complementary modes of action.

Open-label pilot study: Non-invasive vagal nerve stimulation improves symptoms and gastric emptying in patients with idiopathic gastroparesis

BACKGROUND

Gastroparesis, a chronic motility disorder characterized by delayed gastric emptying, abdominal pain, nausea, and vomiting, remains largely unexplained. Medical therapy is limited, reflecting the complex physiology of gastric sensorimotor function. Vagus nerve stimulation is an attractive therapeutic modality for gastroparesis, but prior methods required invasive surgery. In this open-label pilot study, we aimed to assess the benefit of non-invasive vagal nerve stimulation in patients with mild to moderate idiopathic gastroparesis.

METHODS

Patients self-administered the gammaCore vagal nerve stimulator for 4 weeks. The gastroparesis cardinal symptom index daily diary (GCSI-dd) was assessed during a two-week run-in period, ≥4 weeks of therapy, and 4 weeks after therapy was completed. Gastric emptying and autonomic function testing were also performed. The primary endpoint was an absolute reduction in CGSI-dd of 0.75 after nVNS.

RESULTS

There was a total improvement in symptom scores (2.56 ± 0.76 to 1.87 ± 1.05; P = .01), with 6/15 (40%) participants meeting our primary endpoint. Therapy was associated with a reduction in gastric emptying (T1/2 155 vs 129 minutes; P = .053, CI -0.4 to 45). Therapy did not correct autonomic function abnormalities, but was associated with modulation of reflex parasympathetic activity.

CONCLUSIONS

Short-term non-invasive vagal nerve stimulation led to improved cardinal symptoms and accelerated gastric emptying in a subset of patients with idiopathic gastroparesis. Responders had more severe gastric delay at baseline and clinical improvement correlated with duration of therapy, but not with improvements in gastric emptying. Larger randomized sham-controlled trials of greater duration are needed to confirm the results of this pilot study.

Electrogastrographic and autonomic nervous system responses to solid and liquid meals in youth with functional dyspepsia

BACKGROUND

Meal-related symptoms are common in paediatric functional dyspepsia (FD). There are only a small number of paediatric studies assessing mechanisms for meal-related symptoms, and these have not utilized Rome IV criteria. The aim of the current study was to assess gastric myoelectric and autonomic nervous system (ANS) responses to both liquid and solid meals in youth with Rome IV-defined FD.

METHODS

In healthy controls (N = 14) and youth with FD (N = 12), we recorded electrocardiograph (to assess heart rate variability; HRV) and electrogastrograph (EGG) signals before and after two test meals, one liquid and one solid. EGG parameters and HRV were assessed for the entire pre- and postprandial periods and in short time intervals. Additionally, liquid gastric emptying was assessed utilizing a ¹³ C-acetate breath test.

KEY RESULTS

During the EGG, the dominant power increased with both meals in controls but not patients with FD. During HRV assessment, the low frequency to high frequency ratio was higher after the liquid meal in controls, despite being similar preprandial, as compared to patients with FD. In controls, both standard deviation of normal to normal waves (SDNN) and root mean square of successive ECG R peaks (R-R interval) differences (rMSSD) increased after the liquid meal (but not after the solid meal) in controls but not patients with FD.

CONCLUSIONS AND INFERENCES

Youth with Rome IV-defined FD lacks the normal postprandial EGG dominant power response or autonomic nervous system response following a liquid meal. The latter appears to indicate a lack of ANS flexibility.

Wireless motility capsule compared with scintigraphy in the assessment of diabetic gastroparesis

BACKGROUND

Gastroparesis is a potentially severe late complication of diabetes mellitus. Today, delayed gastric emptying (GE) is mandatory for establishing the diagnosis. In this study, we compared wireless motility capsule (WMC) with gastric emptying scintigraphy (GES).

METHODS

Seventy-two patients (49 women) with diabetes mellitus (59 type 1) and symptoms compatible with gastroparesis were prospectively included between 2014 and 2018. Patients were simultaneously examined with GES and WMC. Symptoms were assessed with the Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM) questionnaire. All patients were on intravenous glucose-insulin infusion during testing.

KEY RESULTS

WMC and GES correlated r = .74, P < .001. Compared to GES, WMC at ordinary cutoff for delayed GE (300 minutes) had a sensitivity of 0.92, specificity 0.73, accuracy 0.80, and Cohen's kappa κ = 0.61 (P < .001). By receiver operating characteristics (ROC), the area under the curve was 0.95 (P < .001). A cutoff value for delayed GE of 385 minutes produced sensitivity 0.92, specificity 0.83, accuracy 0.86, and Cohen's kappa κ = 0.72 (P < .001). Inter-rater reliability for GE time with WMC was r = .996, κ = 0.97, both P < .001. There was no difference in symptom severity between patients with normal and delayed GE.

CONCLUSIONS & INFERENCES

Our findings demonstrate the applicability of WMC as a reliable test to assess gastric emptying in diabetic gastroparesis showing very high inter-observer correlation. By elevating the cutoff value for delayed emptying from 300 to 385 minutes, we found higher specificity without reducing sensitivity.

Carbohydrates designed with different digestion rates modulate gastric emptying response in rats

We sought to determine whether design of carbohydrate-based microspheres to have different digestion rates, while retaining the same material properties, could modulate gastric emptying through the ileal brake. Microspheres made to have three slow digestion rates and a rapidly digested starch analogue (maltodextrin) were administrated to rats by gavage and starch contents in the stomach, proximal and distal small intestine, and caecum were measured 2 h post-gavage. A stepwise increase in the amount of starch retained in the stomach was found for microspheres with incrementally slower rates of digestion. Postprandial glycaemic and insulinaemic responses were incrementally lower for the different microspheres than for the rapidly digestible control. A second-meal effect was observed for slowly digestible starch (SDS) microspheres compared to glucose. Thus, dietary slowly digestible carbohydrates were designed to elicit incremental significant changes in gastric emptying, glycaemic and insulinaemic responses, and they may be a means to trigger the ileal brake.

Childhood gastroparesis is a unique entity in need of further investigation

BACKGROUND

Despite increasing knowledge regarding gastroparesis (GP) in adults, little is known regarding the incidence, prevalence, and natural history of childhood GP. Exacerbating the knowledge gap in pediatric GP is both the lack of normative data for gastric emptying scintigraphy in children and lack of GP-specific pediatric reported outcome measures.

PURPOSE

The aim of this article was to review the available literature on pediatric GP and identify similarities and differences with studies in adults. We performed a comprehensive search in MEDLINE and Google Scholar from inception to April 2019 for articles published in English using the following combination of keywords: gastroparesis, pediatric gastroparesis, outcomes, metoclopramide, erythromycin, domperidone, cisapride, and gastric neurostimulator. The limited available pediatric data, often retrospective, suggest marked differences between adult and pediatric GP in several aspects including etiology, concomitant co-morbidities (eg, psychiatric disorders), clinical symptom presentation, diagnostic evaluation, response to therapies, and clinical outcome. Further research in pediatric GP is needed and holds the promise to further elucidate the mechanisms of this disorder in children and lead to pediatric-focused therapies.

The effects of ulimorelin, a ghrelin agonist, on liquid gastric emptying and colonic transit in humans

BACKGROUND

Ulimorelin, a small molecule ghrelin agonist and prokinetic agent, was effective in animal models of gastroparesis and delayed transit. However, employing once daily administration, it failed in clinical trials of postoperative ileus (POI), a condition in which colonic motility recovers last. The aim of this study was to evaluate drug dosing and regional differences in drug activity between stomach and colon.

METHODS

Gastric emptying was assessed by scintigraphy in healthy adults at single doses of 600-1200 µg kg^-1 and multiple doses of 80-600 µg kg^-1 Q8H for 7 days. Colonic motility was assessed by 7-region scintigraphic analysis at a dose of 600 µg kg^-1 for 2 days. The primary endpoints were percent change in time to 50% (∆t₅₀ ) liquid gastric emptying on Days 1, 4, and 6 and the geometric mean center of colonic transit at 24 hours (GC₂₄ ). Plasma concentrations of free and total ulimorelin were measured for pharmacokinetic and exposure-response modeling.

KEY RESULTS

Ulimorelin 150-600 µg kg^-1 every 8 hours resulted in statistically significant improvements (∆t₅₀  = 23% to 46% (P < .05)) in gastric emptying from baseline that were sustained through Day 6. However, no effects on GC₂₄ were observed. Pharmacokinetic analyses suggested that the free concentrations of ulimorelin achieved in POI trials and dosing frequency may have been inadequate.

CONCLUSIONS AND INFERENCES

Ulimorelin is a potent gastric prokinetic but lacks evidence of activity in the human colon, pointing to the stomach as the predominant site of action of ghrelin in humans; ClinicalTrials.gov NCT02993055.

Dietary daidzein decreases food intake accompanied with delayed gastric emptying in ovariectomized rats

We previously found that equol, a metabolite of intestinal bacterial conversion from soy isoflavone daidzein, has female-specific anorectic effects. In the present study, we used seven-week-old female ovariectomized (OVX) Sprague Dawley rats to test the hypothesis that the anorectic effect of dietary daidzein may be attributed to delayed gastric emptying. Results suggest that dietary daidzein delays gastric emptying and that it has an anorectic effect with residual gastric contents, but not without gastric contents. Dietary equol significantly decreased daily food intake in the OVX rats without sleeve gastrectomy, but not in those with sleeve gastrectomy, suggesting that the accumulation of food in the stomach is required for the anorectic effect of equol to occur. These results support the hypothesis that the anorectic effect of dietary daidzein is attributed to delayed gastric emptying.

Thiol/disulfide homeostasis and ischemia modified albumin levels in autoimmune gastritis and their relations with gastric emptying

Background/aim

Autoimmune gastritis is an autoimmune and inflammatory disorder. The aim of this study is to examine dynamic thiol/disulfide homeostasis and ischemia modified albumin levels, and to analyze the association between thiol/disulfide homeostasis and gastric emptying time in autoimmune gastritis.

Materials and methods

Thiol/disulfide homeostasis tests and ischemia modified albumin levels were determined in 50 autoimmune gastritis patients and 53 healthy subjects. Patients with delayed and normal gastric emptying were compared by thiol/disulfide homeostasis tests.

Results

The results showed that native thiol (μmol/L), total thiol (μmol/L), and native thiol/total thiol ratio (%) of the patients with autoimmune gastritis decreased compared to the control group (177.7 ± 34.18 vs. 245.25 ± 33.83, P = 0.001, 227.25 ± 36.78 vs. 284.20 ± 27.19, P = 0.03, and 8.84 ± 1.1 vs. 7.74% ± 1.3%, P = 0.001). In addition, native thiol (μmol/L), total thiol (μmol/L), and native thiol/ total thiol ratio (%) were found to be lower in patients with delayed gastric emptying (198.65 ± 24.27 vs. 167.12 ± 20.51, 241.81 ± 27.14 vs. 213.92 ± 26.35, 8.34 ± 1.29 vs. 7.20 ± 1.83, P = 0.001). Disulfide level, disulfide/native thiol, disulfide/total thiol (P = 0.001) ratios, and ischemia modified albumin levels (ABSU, 0.71 ± 0.08 vs. 0.83 ± 0.07) were found to be higher in autoimmune gastritis patients with delayed gastric emptying (P = 0.001).

Conclusion

The results showed that thiol/disulfide homeostasis in patients with autoimmune gastritis caused an increase in ischemia modified albumin and disulfide whereas a decrease in thiols. An altered thiol/disulfide balance was also observed in patients with delayed gastric emptying. These results suggest that the oxidative process is involved in patients with autoimmune gastritis.

Effects of transportation on gastric pH and gastric ulceration in mares

Background

Transportation has been suggested as a risk factor for gastric ulceration in horses, but limited evidence supports this assumption.

Animals

Twenty‐six Standardbred, Thoroughbred, and Warmblood mares from a university teaching herd.

Methods

Twelve mares were confined for 12 hours, overnight, in reproductive stocks with indwelling nasogastric tubes (NGTs) to assess pH of gastric fluid (GF). Gastric ulceration was assessed endoscopically before and after confinement. Subsequently, 26 horses were transported for 12 hours, overnight, in 2 consignments. During transportation, GF was aspirated from indwelling NGT placed in the same 12 mares used in the confinement study, and gastric ulceration was assessed endoscopically before and after transportation in all horses.

Results

The median pH of GF in confined horses was 1.70‐2.49 at each sampling point, and there was no apparent effect on gastric squamous ulcer scores. The median pH of GF from the same 12 horses at corresponding sampling times during transportation was 6.82‐7.22. Transportation was associated with increased gastric squamous ulcer scores, particularly in horses fasted for gastroscopy and NGT placement immediately before departure. Gastric emptying appeared delayed after transportation in horses fed before departure.

Conclusions and Clinical Importance

Transportation is associated with increased gastric squamous ulceration and with increased pH of GF. These findings may be a consequence of impaired gastric emptying and reflux of alkaline small intestinal content, with factors such as duodenal bile salts and short‐chain fatty acids mediating mucosal injury.

Gastroparesis versus dyspepsia by intragastric meal distribution: new diagnostics and definitions ahead

Gastroparesis often presents a challenge to the practicing gastroenterologist. Postprandial symptoms with nausea and vomiting may not only lead to nutritional and metabolic consequences, but also significant disruption of social activities that often center around food. The treatment options that affect gastric function are limited and often disappointing. The female predominance, the mostly idiopathic and idiosyncratic nature of the illness, often with some common psychiatric co-morbidity, parallels other functional disorders of the gastrointestinal tract. These parallels have provided the rationale for studies investigating alternative diagnostic features of the gastric emptying test as employed in the clinical setting. Hence, not only the regular cut-offs of 60% or 10% gastric retention of a meal at 2 and 4 h, but also a new concept, the intragastric meal distribution at time 0 (IMD⁰) is now introduced as a plausible diagnostic feature that should be more aligned with the patients' symptoms as they appear in close connection with the meal. Impaired gastric accommodation with absence of fundic relaxation followed by dumping of the meal into antrum is suggested to be diagnostic for functional dyspepsia and gastroparesis. The diagnostic cut-off is considered when more than 57% of the meal is distributed to the distal part of the stomach immediately on food intake. This new diagnostic feature of the gastric emptying profile lend support to better understanding of the patients' symptoms and provides a new basis for pharmacological treatment options in gastroparesis that may provide an improved quality of life in affected individuals.

Ghrelin abates bacterial translocation following burn injury by improving gastric emptying

BACKGROUND

In severe burns, increased intestinal permeability facilitates bacterial translocation, resulting in systemic endotoxemia and multi^- organ failure. We investigated the role of burn-induced gastrointestinal dysmotility (BIGD) in promoting bacterial translocation following burn injury, and the protective effect of ghrelin in this process.

METHODS

We assessed gastric emptying (GE%) and intestinal transit (IT by geometric center "GC") in a 60% total body surface area scald burn rat model and measured bacterial counts in mesenteric lymph nodes (MLN) and distal small intestine by colony-forming unit per gram of tissue (CFU/g). A group of animals was treated with ghrelin or saline after burn.

KEY RESULTS

Scald burn was associated with a significant delay in GE (62% ± 4% vs 74% ± 4%; P = .02) and a trend of delay in intestinal transit (GC: 5.5 ± 0.1 vs 5.8 ± 0.2; P = .09). Concurrently, there was a marginal increase in small intestinal bacterial overgrowth (6 × 10⁵ vs 2 × 10⁵  CFU/g; P = .05) and significant translocation to MLN (2 × 10² vs 4 × 10¹ ; P = .03). We observed a negative correlation between GE and intestinal bacterial overgrowth (r_s  = -0.61; P = .002) and between IT and translocation (r_s  = -0.63; P = .004). Ghrelin administration significantly accelerated GE following burn injury (91% ± 3% vs 62% ± 4; P = .03), reduced small intestinal bacterial overgrowth, and completely inhibited translocation to MLN (0.0 vs 5 × 10² ; P = .01).

CONCLUSIONS & INFERENCES

Burn-induced gastrointestinal dysmotility is correlated with the systemic translocation of gram-negative gut bacteria that are implicated in multiple organ failure in burn patients. Therapeutic interventions to restore BIGD are warranted (Neurogastroenterol Motil, 2012, 24, 78).