This pilot, randomized, double-blind trial in a relatively small sample of patients with IBS-related pain shows rimegepant significantly reduced sensations of gas, urgency, and pain during rectal distention and decreased rectal compliance. Decrease in compliance implies that changes in physical properties or distensibility of rectum did not contribute to alterations in rectal sensation. Same dose of rimegepant did not significantly impact daily abdominal pain, BM frequency, or colonic transit. There were no serious adverse events.
Effects of Ricinoleic Acid (Castor Oil) on Gut Permeability in Healthy Participants: Provocative Test for Treatments Aimed at Restoring Barrier Function
INTRODUCTION: Altered intestinal permeability (IP) is implicated in multiple gastrointestinal and systemic disease conditions; an experimental model of perturbed IP in healthy subjects is needed. Traditional approaches to perturbing IP include use of nonsteroidal anti-inflammatory drugs. METHODS: We conducted a single-center, randomized, placebo-controlled pilot study of dose-related effects of castor oil (CO) (and its ingredient ricinoleic acid) at 750, 1,500, or 3,000 mg daily doses on IP. Permeability was assessed using validated 13 C-mannitol and lactulose urine excretion at 0–2, 8–24, and 0–24 hours after oral administration. RESULTS: Permeability analysis across all groups demonstrated significant difference among the groups for 0–2 hours 13 C-mannitol, 0–24 hours 13 C-mannitol, and borderline significant difference for 2–8 hours 13 C-mannitol ( P = 0.060) and 0–24 hours lactulose ( P = 0.056). Direct comparison of 3,000 mg CO vs placebo ( t test) demonstrated higher excretion of 13 C-mannitol and lactulose at 0–2, and 0–24 hours, and lactulose at 2–8 hours. DISCUSSION: CO may perturb small intestinal and colonic permeability in healthy adults.
Intestinal Permeability In Vivo in Patients With Inflammatory Bowel Disease: Comparison of Active Disease and Remission
Abstract Background and Aims Inflammatory bowel disease (IBD) is associated with altered mucus and increased intestinal permeability (IP). Prior reports on permeability in IBD typically used lactulose-to-mannitol ratio (LMR). Food contamination with 12C-mannitol is a significant potential confounder in IP assessment. We aimed to compare small intestinal (SI) and colonic (COL) permeability in IBD, both active (ACT) and in remission (REM), to normal healthy volunteers (NHV). Methods Inflammatory bowel disease activity was based on Simple Endoscopic Score for Crohn’s Disease (SES-CD) and Mayo endoscopy score for ulcerative colitis (UC). We performed 24-hour IP test using 100 mg 13C-mannitol and 1000 mg lactulose with urine collected during 0-2, 2-8, and 8-24 hours. The primary endpoint was mg excretion of 13C-mannitol and lactulose during 2-24 hours reflecting SI and COL permeability. Results Among 17 CD patients, 7 were ACT (SES-CD >6), and 10 REM (SES-CD 0-2). Among 20 UC patients, 10 had ACT (Mayo score 2-3), and 10 REM (Mayo score 0-1). Urinary excretions over 2-24 hours were higher for IBD than NHV: 13C-mannitol (13.8 [IQR 8.8, 18.7] NHV; 18.4 [15.6, 29.9] REM; 19.7 [13.8, 23.6] ACT, P = .003) and lactulose (1.8 [1.3, 3.1] NHV; 3.6 [2.0, 5.0] REM; 3.5 [2.0, 6.6] ACT, P = .006). There was no difference between ACT and REM for any timed urine collection. LMR at 2-24 hours (or 2-8 and 8-24 hours) were not statistically significant between the 3 groups (0.014 [0.010, 0.021] NHV; 0.016 [0.010, 0.023] REM; 0.016 [0.012, 0.038] ACT, P = .237). Conclusions Intestinal permeability is increased in IBD using validated in vivo assay relative to NHV; increased IP in IBD persists during remission.
S801 Dose-Related Effects of Ricinoleic Acid (Castor Oil) on Gut Permeability in Healthy Participants: Provocative Test for Treatments Aimed at Restoring Barrier Function
AbstractBackgroundColonic transit (CT) measured by validated scintigraphy using 111In‐labeled activated charcoal particles is summarized using geometric center (GC) of isotopic distribution in four colonic regions and stool at 24 and 48 h. Diagnosis of rapid CT is currently based on GC24 ≥4.4 in females and >4.7 in males, which lack sensitivity. Our aim was to evaluate, in patients with chronic diarrhea with normal CT by GC24 and GC48, the diagnostic utility of CT change (∆GC) relative to sex‐matched normal values.MethodsWe evaluated two adult patient cohorts: 701 clinical patients (1994–2023) with chronic diarrhea and 76 research participants with irritable bowel syndrome with diarrhea (N = 63) or bile acid diarrhea (BAD, N = 13). Results of ∆GC were compared to 220 healthy controls' 95th percentiles (%ile) (≥2.0 females and ≥2.2 males). In the research cohort, we also analyzed (Spearman correlation) colonic ∆GC with ascending colon emptying T1/2 (AC T1/2), average stool frequency and consistency based on a daily diary, total fecal bile acid (BA) concentration, and % primary BA in a single stool sample.Key ResultsAmong 701 clinical patients with normal GC24, 160 (22.3%) had rapid CT based on ∆GC 95th %ile in health. Among 76 research participants, an additional 20.6% IBS‐D and 23% BAD had rapid CT ∆GC. Younger age and absence of diabetes mellitus were predictive of rapid ∆GC. ∆GC significantly correlated with AC T1/2 and with fecal BA.Conclusions & Inferences∆GC identified an additional 21%–23% patients with rapid colonic transit among patients with diarrhea and normal GC24.
Optimal measurement of gastric emptying of solids in gastroparesis or functional dyspepsia: evidence to establish standard test
Objective Symptoms in gastroparesis (Gp) and functional dyspepsia (FD) overlap; using egg protein substitute to measure gastric emptying of solids (GES), ~40% of patients are reclassified from Gp to FD, and vice versa. Our aim was to assess inter-individual and intra-individual coefficients of variation (COV) in GES in symptomatic patients with Gp or FD with documented slow or normal GES, respectively. Design Scintigraphic GES (T1/2 and GE% at 2 and 4 hours) using a 320 kcal real egg meal (30% fat) was tested in the following: single measurements in 20 patients with diabetes mellitus (10 each type 1 and type 2); repeat GES to estimate COVintra measured: 3 days apart in 9 Gp, 4 weeks apart in 21 Gp and 18 with FD with normal GE assigned to placebo and in 70 patients at 94.3 weeks (median) apart. Results COVinter for GE% at 4 hours and GE T1/2 were respectively 14.2% and 23.5% in FD and 27.5% and 33% in Gp; COVintra for GE% at 4 hours and GE T1/2 up to 4 weeks apart were 23.4% and 37.9% in FD and 20.1% and 33% in Gp. GE% at 2 hours showed less consistent results. However, >85% retained original diagnosis as normal or delayed. From clinical GES to baseline research for Gp group, repeat GES (after treatment) showed the COVintra for GE% at 4 hours was 37.3% at median 94.3 weeks, with 26/70 changed diagnoses. Conclusion The 320 kcal (30% fat) GES scintigraphic test provides consistent diagnosis in >85% and should be the standard test for suspected gastric emptying disorders.
Factors associated with successful weight loss after liraglutide treatment for obesity
Abstract Aim To identify patient factors, including gastrointestinal functions, that are predictive or associated with weight loss in response to once‐daily 3 mg liraglutide administered subcutaneously (SQ) or placebo in obesity. Methods One hundred and thirty‐six obese adults (87% female) were randomized in a placebo‐controlled, 16‐week trial of liraglutide, escalated to 3 mg administered SQ daily. Gastrointestinal functions were measured at baseline and 16 weeks: gastric emptying of solids (GET 1/2 ); fasting and postprandial gastric volumes; kcal ingested during ad libitum buffet meal and the nutrient drink test. GET 1/2 was also measured at 5 weeks. A multiple variable regression model examined variables associated with weight loss of more than 4 kg at 16 weeks. A parsimonious model using backward selection identified the final model. Results Weight loss of more than 4 kg at 16 weeks occurred in 71% of liraglutide‐ and 16% of placebo‐treated patients. In all participants combined, parameters univariately associated with a weight loss of more than 4 kg were GET 1/2 at 5 and 16 weeks, weight loss at 5 weeks and kcal intake during the buffet meal at 16 weeks. The final parsimonious model (area under the receiver operator characteristics [AUROC] curve = 0.832) identified that factors associated with more than 4‐kg weight loss were GET 1/2 at 5 weeks (OR = 2.505; 95% CI: 1.57‐3.997) per 50 minutes and kcal intake during ad libitum meal at 16 weeks (OR = 0.721; 95% CI: 0.602‐0.864) per 100 kcal. Among only the 60 liraglutide‐treated subjects, kcal intake at 16 weeks was associated with 4‐kg weight loss (AUROC = 0.757). Conclusions Slower GET 1/2 and weight loss at 5 weeks predicted a weight loss of more than 4 kg at 16 weeks in all participants. Among liraglutide‐treated adults, weight loss of more than 4 kg was associated with ad libitum meal kcal intake at 16 weeks.
Effects of liraglutide on gastrointestinal functions and weight in obesity: A randomized clinical and pharmacogenomic trial
Abstract Objective This study aimed to determine the effects of a long‐acting glucagon‐like peptide‐1 (GLP‐1) receptor agonist, liraglutide, and placebo subcutaneously over 16 weeks on weight and gastric functions and to evaluate associations of single‐nucleotide polymorphisms in GLP1R (rs6923761) and TCF7L2 (rs7903146) with effects of liraglutide. Methods The study conducted a randomized, parallel‐group, placebo‐controlled, 16‐week trial of liraglutide, escalated to 3 mg subcutaneously daily in 136 otherwise healthy adults with obesity. Weight, gastric emptying of solids (GES), gastric volumes, satiation, and body composition measured at baseline and after treatment were compared in two treatment groups using analysis of covariance. Results Liraglutide ( n = 59) and placebo ( n = 65) groups completed treatment. Relative to placebo, liraglutide increased weight loss at 5 and 16 weeks (both p < 0.05), slowed time to half GES (T 1/2 ) at 5 and 16 weeks (both p < 0.001), and increased fasting gastric volume ( p = 0.01) and satiation ( p < 0.01) at 16 weeks. GES T 1/2 was positively correlated with weight loss on liraglutide (both p < 0.001). After 16 weeks of liraglutide, GLP1R rs6923761 (AG/AA vs. GG) was associated with reduced percent body fat ( p = 0.062), and TCF7L2 rs7903146 (CC vs. CT/TT) was associated with lower body weight ( p = 0.015). Conclusions Liraglutide, 3 mg, induces weight loss with delay in GES T 1/2 and reduces calorie intake. Slowing GES and variations in GLP1R and TCF7L2 are associated with liraglutide effects in obesity.
Comprehensive characterization of antral and pyloric contractions by high resolution manometry: applied physiology in suspected gastroparesis
Current selection of different treatments for patients with gastroparesis is empiric or based on trial and error, though pyloric distensibility and diameter may predict response to pyloric interventions. High-resolution antropyloroduodenal manometry (HR-ADM) can characterize a variety of postprandial antral contractile and pyloric motility dysfunctions in patients with suspected gastroparesis. HR-ADM shows promise to provide guidance for selection and individualization of treatments such as prokinetic agents or pyloric interventions for patients with gastroparesis based on documented pathophysiology.
Liraglutide reduces attenuation coefficient as a measure of hepatic steatosis during 16 weeks' treatment in nondiabetic obese patients: A pilot trial
AbstractBackground and AimLiraglutide, a long‐acting GLP‐1 analog, is approved for the treatment of obesity with improvements in fasting blood glucose, hemoglobin A1c, and cardiovascular health. Our aim was to measure the impact of liraglutide dose for obesity on hepatic steatosis measured by ultrasound.MethodsA single‐center, randomized, double‐blind, placebo‐controlled pilot trial was undertaken in nondiabetic obese, otherwise healthy patients aged 18–65 years. Participants were randomly assigned to receive subcutaneous liraglutide (3.0 mg) or placebo over 16 weeks with dose escalation following US Food and Drug Administration guidelines. Both groups received standardized nutritional and behavioral counseling during the 16 weeks. Hepatic fat content was measured by ultrasound at baseline, 8 weeks, and 16 weeks as an attenuation coefficient (ACE). Effects of treatment were assessed using t‐test for the entire groups and for patient subgroup with baseline ACE >0.66 (indicating significant steatosis).ResultsAmong 30 patients (93% female) enrolled, 16 were randomized to placebo and 14 to liraglutide. Baseline body mass indices (BMIs) and average age were similar in the two groups. After 16 weeks, the liraglutide group had a significant improvement in steatosis ACE scores (−0.068 ± 0.02 vs −0.0077 ± 0.02 placebo, P = 0.05). Change in steatosis was positively correlated with change in BMI (R2 = 0.402, P = 0.0007). Within the liraglutide group, patients with baseline ACE >0.66 had improvement in ACE (−0.134 ± 0.03) compared to those without significant steatosis (−0.041 ± 0.02, P = 0.05).ConclusionsIn this pilot trial, liraglutide, 3.0 mg over 16 weeks, reduced hepatic steatosis; a reduction in hepatic steatosis is correlated with BMI reduction, and effects are particularly evident in those with a significant degree of steatosis by ultrasound imaging.