Celiac Disease and Gallbladder: Pathophysiological Aspects and Clinical Issues.

Background: Celiac Disease (CD) is an immune-mediated disorder which primarily affects the small intestine; however, extra-intestinal organs are often affected by the pathological process, too. As regards the digestive system, liver alterations in CD patients have been widely described, which can also extend to the biliary tract. Notably, gallbladder function can be altered in CD patients. In this review, we specifically analyze and summarize the main pathophysiological aspects and clinical evidence of gallbladder dysfunction in CD patients, in order to discuss the potential medical complications and clinical research gaps. In addition to some perturbations of bile composition, CD patients can develop gallbladder dysmotility, which mainly expresses with an impaired emptying during the digestive phase. The main pathophysiological determinant is a perturbation of cholecystokinin secretion by the specific duodenal enteroendocrine cells in response to the appropriate nutrient stimulation in CD patients. This situation appears to be reversible with a gluten-free diet in most cases. Despite this gallbladder impairment, CD patients do not seem to be more predisposed to gallbladder complications, such as calculous and acalculous cholecystitis. However, very few clinical studies have actively investigated these clinical aspects, which may not be completely evidenced so far; alternatively, the substantial improvements in the last two decades regarding CD diagnosis, which have reduced the diagnostic delay (and related dietary treatment), may have lessened the potential clinical consequences of CD-related gallbladder dysfunction. Specific clinical studies focused on these aspects are needed for a better understanding of the clinical implications of gallbladder alterations in CD patients.

Relationship between gallstones and interstitial cells of Cajal in the gallbladder.

INTRODUCTION: A high percentage of patients with gallstones exhibit abnormalities in gallbladder emptying, and gallstones are often associated with gallbladder contraction. Interstitial cells of Cajal (ICC) in the gallbladder are involved in the generation and spreading of spontaneous contractions of the gallbladder. This study examined the relationship among the number of gallbladder ICC, gallbladder contractility, and gallstones. MATERIALS AND METHODS: Forty-six patients, who underwent cholecystectomy within 3 months of enduring a gallbladder ejection fraction scan, were enrolled in this study. ICC were identified using a microscope after immunohistochemical staining for CD117/c-kit. Five high-power field (magnification 400×) units were randomly assigned, and the number of ICC in the mucosal and muscular layers was counted. These counts were compared according to the sex, age, reason for cholecystectomy, presence of gallstone, presence of gallbladder polyp, gallbladder ejection fraction, and gallbladder size for each patient. RESULTS: The number of ICC in the mucosal layer was increased in the male participants (154.4 ± 73.9) compared with the female participants (107.3 ± 75.2); however, the ICC in the muscular layer was not different between the 2 groups. Additionally, the ICC in the mucosal and muscular layers did not differ according to age, cause of cholecystectomy, number of stones, stone character, stone diameter, or the presence of polyps. A larger gallbladder size was correlated with a decreased number of ICC in the muscular layer of the gallbladder. Additionally, when the number of gallbladder stones was increased, the number of ICC in the muscular layer of the gallbladder was decreased; however, there was no significant correlation between the number of ICC in the mucosal layer of the gallbladder and any of the following factors: age, GBEF, gallbladder size, stone number, or diameter. Furthermore, there was no significant correlation between the number of ICC in the muscular layer of the gallbladder, regardless of age, GBEF, and stone diameter. CONCLUSION: Although we were unable to achieve significant results regarding the relationship between GBEF and ICC, this is the first human study to reveal the relationship among ICC, gallbladder size, and the number of gallstones.

Sincalide-Stimulated Cholescintigraphy: A Retrospective Study and Proposal of a Modified Workflow.

PURPOSE: Current guidelines for sincalide-stimulated cholescintigraphy (SSC) call for a 60-minute sincalide infusion, and a gallbladder ejection fraction (GBEF) ≥38% is considered normal. In this retrospective study, we hypothesize that most patients reach a normal GBEF by 30 minutes. METHODS: Eligible patients had undergone a 60-minute SSC from January to December 2019. The clinical SSC data were previously processed on a Xeleris workstation (GE Healthcare). In subjects with GBEF ≥38% based on standard SSC, the GBEF at 20 minutes and 30 minutes were retrospectively calculated using manual pixel height measurements. Receiving operating characteristic was analyzed to determine the best GBEF cutoff at 30 minutes. RESULTS: Of 302 subjects, mean age of 46 ± 17 years, 33 (10.9%) showed an abnormal GBEF <38% suggestive of functional gallbladder disorder. In the remaining 269 patients (89.1%) with a normal GBEF, 60.6% and 86.6% reached a normal GBEF at 20 minutes and 30 minutes, respectively. Moreover, a GBEF threshold >29.1% at 30 minutes was associated with a negative predictive value of 99.6%, indicating that a 60-minute SSC was not necessary. The GBEF values were not associated with sex, age, patient symptoms, or type of referral. Manually calculated GBEFs on the time-activity curve showed excellent correlation with the primary values. We propose a modified workflow that splits the 60-minute SSC into two 30-minute image sets to allow for a screening GBEF at 30 minutes. If GBEF is >29.1% at 30 minutes, the second image set may be stopped, and the examination is complete. CONCLUSIONS: The majority of patients (77.2%) undergoing the standard 60-minute SSC reach a normal GBEF already by 30 minutes. The proposed workflow shortens the SCC procedure by 30 minutes, while maintaining high diagnostic accuracy and contributing to improved procedure efficiency and reduced patient discomfort as well as symptoms.

Clinical utility of stimulated cholescintigraphy using a standardized Ensure-Plus fatty meal protocol in patients with suspected functional gallbladder disorder: a retrospective study of seven-years clinical experience.

BACKGROUND: The clinical utility of fatty meal stimulated cholescintigraphy particularly using a standardized formulation in patients with suspected functional gallbladder disorder has not been extensively studied. We present our seven-year clinical experience using an Ensure plus protocol. METHODS: A retrospective study was performed on patients undergoing stimulated cholescintigraphy using Ensure Plus for evaluation of suspected functional gallbladder disorder. A gallbladder ejection fraction (GBEF) of <33% was considered abnormal. RESULTS: Of the 173 patients evaluated, 57 (33%) had an abnormal GBEF, 112 (65%) had a normal GBEF and 4 (2%) had no gallbladder visualization. Of the 57 patients with an abnormal GBEF, symptom improvement occurred in 30/31 (97%) who underwent cholecystectomy and in 17/26 (65%) who were managed conservatively (p = 0.003). Of the 112 patients with a normal GBEF, symptom improvement occurred in 8/10 (80%) who underwent cholecystectomy and 74/102 (73%) who were managed conservatively (p = 1.000). In the subgroup of 102 patients with a normal GBEF managed conservatively, those without symptomatic improvement had lower GBEFs compared to those with symptomatic improvement (median GBEF 46% versus 57%, p = 0.019). CONCLUSION: Our retrospective results support a clinical role for stimulated cholescintigraphy using Ensure Plus in the evaluation of patients with suspected functional gallbladder disorder. While an abnormal GBEF predicts good surgical outcome, our results suggest that using an absolute GBEF cut off value of <33% may not apply to all patients and hence GBEF results should only be used as an adjunct in the surgical decision-making process.

An Update on the Lithogenic Mechanisms of Cholecystokinin a Receptor (CCKAR), an Important Gallstone Gene for Lith13.

The cholecystokinin A receptor (CCKAR) is expressed predominantly in the gallbladder and small intestine in the digestive system, where it is responsible for CCK's regulation of gallbladder and small intestinal motility. The effect of CCKAR on small intestinal transit is a physiological response for regulating intestinal cholesterol absorption. The Cckar gene has been identified to be an important gallstone gene, Lith13, in inbred mice by a powerful quantitative trait locus analysis. Knockout of the Cckar gene in mice enhances cholesterol cholelithogenesis by impairing gallbladder contraction and emptying, promoting cholesterol crystallization and crystal growth, and increasing intestinal cholesterol absorption. Clinical and epidemiological studies have demonstrated that several variants in the CCKAR gene are associated with increased prevalence of cholesterol cholelithiasis in humans. Dysfunctional gallbladder emptying in response to exogenously administered CCK-8 is often found in patients with cholesterol gallstones, and patients with pigment gallstones display an intermediate degree of gallbladder motility defect. Gallbladder hypomotility is also revealed in some subjects without gallstones under several conditions: pregnancy, total parenteral nutrition, celiac disease, oral contraceptives and conjugated estrogens, obesity, diabetes, the metabolic syndrome, and administration of CCKAR antagonists. The physical-chemical, genetic, and molecular studies of Lith13 show that dysfunctional CCKAR enhances susceptibility to cholesterol gallstones through two primary mechanisms: impaired gallbladder emptying is a key risk factor for the development of gallbladder hypomotility, biliary sludge (the precursor of gallstones), and microlithiasis, as well as delayed small intestinal transit augments cholesterol absorption as a major source for the hepatic hypersecretion of biliary cholesterol and for the accumulation of excess cholesterol in the gallbladder wall that further worsens impaired gallbladder motor function. If these two defects in the gallbladder and small intestine could be prevented by the potent CCKAR agonists, the risk of developing cholesterol gallstones could be dramatically reduced.

Kinetics of Gallbladder Emptying During Cholecystokinin Cholescintigraphy as an Indicator of In Vivo Hormonal Sensitivity.

Cholecystokinin cholescintigraphy is used clinically to quantify gallbladder ejection fraction as an indicator of functional gallbladder disorder. It can also provide the opportunity to quantify an individual's responsiveness to the physiologic stimulant of gallbladder contraction, cholecystokinin, which is a major regulator of appetite and postprandial satiety. Methods: In the current work, we use cholecystokinin cholescintigraphy to quantify the kinetics of gallbladder emptying, including average and peak rates, in response to a standard cholecystokinin infusion. Results: We demonstrated that patients with no gallstones or biliary obstruction who empty their gallbladders completely in response to cholecystokinin, having an ejection fraction greater than 80%, exhibit a broad range of sensitivity to this hormone. Three distinct kinetic profiles were observed, with those most sensitive to cholecystokinin achieving the earliest peak and the fastest rate of gallbladder emptying, whereas those least sensitive to cholecystokinin have the latest peak and the slowest rate of emptying. Conclusion: Patients can have abnormal cholecystokinin stimulus-activity coupling as an effect of endogenous negative allosteric modulation by membrane cholesterol. This was predicted in ex vivo studies but has not, to our knowledge, previously been demonstrated in vivo. This type of kinetic analysis provides a tool to quantify cholecystokinin responsiveness in patients and identify patients who might benefit from a drug that would positively modulate cholecystokinin action to improve their appetite regulation and to better control their weight.

Glucagon-Like Peptide 2 Inhibits Postprandial Gallbladder Emptying in Man: A Randomized, Double-Blinded, Crossover Study.

INTRODUCTION: A recent study in mice points to the gut-derived hormone glucagon-like peptide 2 (GLP-2) as an important regulator of gallbladder motility inducing gallbladder relaxation and refilling. In this study, we evaluated the effect of exogenous GLP-2 on postprandial gallbladder motility in healthy men. METHODS: In a randomized, double-blinded, placebo-controlled, crossover study, we evaluated the effect of 4-hour intravenous infusions of high-dose GLP-2 (10 pmol × kg × min), low-dose GLP-2 (1 pmol × kg × min), and placebo (saline) on postprandial gallbladder motility. A 300-kcal liquid-mixed meal (added 1.5 g of acetaminophen for indirect measurement of gastric emptying) was served 30 minutes after start of intravenous infusions. Gallbladder volume was assessed by ultrasonography. RESULTS: Fifteen healthy men, age 24.3 (22.4-26.1) years (mean [95% confidence interval]) and body mass index 22.5 (21.7-23.4) kg × m, were included. Basal plasma GLP-2 concentration was 14 (11-17) pmol/L. During low-dose and high-dose GLP-2 infusions, steady-state postprandial plasma GLP-2 concentrations amounted to 201 (188-214) and 2,658 (2,443-2,873) pmol/L, respectively, compared with maximum postprandial plasma GLP-2 concentration of 34 (25-44) pmol/L during placebo. Gallbladder emptying (assessed as baseline-subtracted area under the curve for gallbladder volume) was reduced by low-dose GLP-2 (-0.8 [0.7-1.9] L × min, P < 0.0001) and nearly abolished by high-dose GLP-2 (1.3 [-1.7 to 0.01] L × min, P = 0.029) compared to placebo (-2.0 [-2.8 to -1.1] L × min). Compared to placebo, gastric emptying was reduced by high-dose GLP-2 (P = 0.0060 and 0.019), whereas low-dose GLP-2 did not affect gastric emptying (P = 0.13 and 0.85). DISCUSSION: Exogenous GLP-2 exerts a dose-dependent inhibitory effect on postprandial gallbladder emptying in healthy men.

Utilizing the Cholecystagogue, Ensure Plus, Results in Similar Hepatobiliary Scintigraphy Study Results and Patient Outcomes Status Post Cholecystectomy, in Comparison With Sincalide.

OBJECTIVE: To determine if use of the oral cholecystagogue, Ensure Plus (EP), in hepatobiliary scintigraphy (HBS) leads to a similar distribution of normal and abnormal gallbladder ejection fractions (GBEFs) versus other historical secondary findings of chronic biliary disease in a similar patient population compared with the conventional cholecystokinin analog, sincalide. The HBS findings analyzed included the GBEF, small bowel transit time, gallbladder fill time, and reversal of the normal gallbladder versus small bowel transit. The secondary objectives were to determine whether patient outcomes were significantly different for EP and sincalide HBS study patients following cholecystectomy, namely, the surgical pathology and patient-reported biliary-type pain. METHODS: We reviewed all HBS examinations over a retrospective 34-month period. Data from 446 patients who underwent sincalide or EP HBS with GBEF determination for evaluation of chronic symptoms concerning for biliary etiology met the inclusion criteria. The aforementioned HBS findings and postsurgical patient outcomes were obtained for each patient group. RESULTS: Comparing HBS examinations performed with sincalide or EP, no significant differences were noted in the major HBS findings of similar patient populations. Outcomes for the sincalide and EP groups status post cholecystectomy were assessed to determine their sensitivity, specificity, positive predictive value, and negative predictive value. The outcomes assessed were the histopathology and patient-reported amelioration of biliary-type pain. No significant differences were noted. CONCLUSIONS: The sincalide and EP cholecystagogues did not lead to significantly different HBS findings for similar patient populations or postcholecystectomy outcomes.

Sourdough Fermented Breads are More Digestible than Those Started with Baker's Yeast Alone: An In Vivo Challenge Dissecting Distinct Gastrointestinal Responses.

As a staple food, bread digestibility deserves a marked nutritional interest. Combining wide-spectrum characterization of breads, in vitro nutritional indices, and in vivo postprandial markers of gastrointestinal function, we aimed at comparing the digestibility of sourdough and baker's yeast breads. Microbiological and biochemical data showed the representativeness of the baker´s yeast bread (BYB) and the two sourdough breads (SB and t-SB, mainly differing for the time of fermentation) manufactured at semi-industrial level. All in vitro nutritional indices had the highest scores for sourdough breads. Thirty-six healthy volunteers underwent an in vivo challenge in response to bread ingestion, while monitoring gallbladder, stomach, and oro-cecal motility. SB, made with moderate sourdough acidification, stimulated more appetite and induced lower satiety. t-SB, having the most intense acidic taste, induced the highest fullness perception in the shortest time. Gallbladder response did not differ among breads, while gastric emptying was faster with sourdough breads. Oro-cecal transit was prolonged for BYB and faster for sourdough breads, especially when made with traditional and long-time fermentation (t-SB), whose transit lasted ca. 20 min less than BYB. Differences in carbohydrate digestibility and absorption determined different post-prandial glycaemia responses. Sourdough breads had the lowest values. After ingesting sourdough breads, which had a concentration of total free amino acids markedly higher than that of BYB, the levels in blood plasma were maintained at constantly high levels for extended time.

Gallbladder interstitial Cajal-like cells and gallbladder contractility in patients with cholelithiasis: a prospective study.

INTRODUCTION: A reduced number of interstitial Cajal-like cells (ICLCs) in the gallbladder have been proposed to play a role in the pathogenesis of cholelithiasis. Therefore, this prospective study was conducted to investigate the relationship between gallbladder contractility and the number of gallbladder ICLCs in patients with cholelithiasis. MATERIAL AND METHODS: Patients admitted to the Department of Hepatobiliary Surgery for cholecystectomy were divided into the cholelithiasis (n = 18) and non-cholelithiasis (n = 8) groups based on their clinical data. Patients' clinical data were collected on admission, and B-mode ultrasonography was performed to assess their gallbladder contractility. The resected gallbladder specimens were fixed, paraffin sections mounted on slides, and the immunofluorescence staining with the anti-human CD-117 and anti-human tryptase antibodies was performed to identify ICLSs and mast cells, respectively. The number of ICLCs was counted in 10 high-power fields (HPFs) randomly. RESULTS: Independent sample t-tests revealed differences between the cholelithiasis and non-cholelithiasis groups in the number of ICLCs (mean ± standard deviation: 88.61 ± 28.22 vs. 115.89 ± 27.87 per HPFs, P = 0.032) and gallbladder contractility (43.94% ± 18.50% vs. 61.00% ± 20.50%, P = 0.046). Pearson and Spearman cor-relation analyses revealed no significant correlation between the number of ICLCs and gallbladder contractility. CONCLUSION: The results suggest that the number of gallbladder ICLCs in the wall of the gallbladder of patients with or without cholelithiasis is not a decisive factor affecting gallbladder contractility.

Systematic review with meta-analysis: cholecystectomy for biliary dyskinesia-what can the gallbladder ejection fraction tell us?

BACKGROUND: Gallbladder dyskinesia (gallbladder spasm, biliary dyskinesia or chronic acalculous cholecystitis) is a poorly defined entity which presents as biliary-type pain without any identifiable organic pathology. Abnormal gallbladder ejection fraction (GBEF) is used by some to select those likely to benefit from cholecystectomy. The validity of this approach has been questioned. AIM: To systematically review the literature and summarise the evidence surrounding the practice of cholecystectomy based on GBEF for gallbladder dyskinesia. METHODS: We conducted a systematic search of PubMed/MEDLINE and SCOPUS from 1980 to 2016 to identify the relevant literature. RESULTS: Twenty-nine studies including 2891 patients were included in the final analysis. In comparing cholecystectomy with medical management, patients with a normal GBEF did not benefit from cholecystectomy; whereas those with low GBEF had a higher chance (RR, relative risk = 2.37) of symptomatic improvement following surgery. When those classified as "low" and "normal" GBEF were compared in terms of outcome following cholecystectomy, the rate of improvement following surgery was similar in the two groups (RR 1.09) which suggests a placebo effect of surgery. CONCLUSIONS: While a low GBEF may provide some guidance in identifying those with gallbladder dyskinesia who may benefit from cholecystectomy, the available data are inconsistent and based on studies of poor quality which are often subject to bias and the impact of confounding factors. For these reasons, we conclude that the role of scintigraphy and cholecystectomy in the definition and management of this disorder remain unclear pending definitive study.

Gastrointestinal defects in gallstone and cholecystectomized patients.

BACKGROUND AND AIM: Several gallstone patients complain of dyspeptic symptoms, irrespective of the presence of typical colicky pain. Symptoms often persist after a cholecystectomy. Systematic studies on dyspepsia and dynamic gastrointestinal motor function are missing in gallstone patients with preserved gallbladder or after a cholecystectomy. MATERIALS AND METHODS: Forty-six gallstone patients (age 55 ± 2 years; 15M, 31F) and 24 cholecystectomized patients (age 57 ± 2 years; 6M, 18F) (no difference in type and volume of gallstones between the two groups) were compared against a group of 65 healthy controls (age 51 ± 2 years; 30M, 35F). Dyspepsia occurring in the prior months was assessed by a questionnaire, gastric and gallbladder emptying by functional ultrasonography and orocecal transit time by a hydrogen breath test using a lactulose-enriched standard liquid meal. RESULTS: Gallstone patients had significantly greater dyspepsia, fasting and residual gallbladder volumes, and slower gallbladder emptying, gastric emptying and small intestinal transit time than controls. In cholecystectomized patients, gastric emptying further delayed, compared to gallstone patients and controls. CONCLUSION: Gallstone patients with the gallbladder "in situ" or after a cholecystectomy display dyspeptic symptoms. Symptoms are associated with multiple gastrointestinal motility defects involving the gallbladder, stomach and small intestine. After cholecystectomy, gastric emptying worsens.

New Avenues in the Regulation of Gallbladder Motility-Implications for the Use of Glucagon-Like Peptide-Derived Drugs.

CONTEXT: Several cases of cholelithiasis and cholecystitis have been reported in patients treated with glucagon-like peptide 1 (GLP-1) receptor agonists (GLP-1RAs) and GLP-2 receptor agonists (GLP-2RAs), respectively. Thus, the effects of GLP-1 and GLP-2 on gallbladder motility have been investigated. We have provided an overview of the mechanisms regulating gallbladder motility and highlight novel findings on the effects of bile acids and glucagon-like peptides on gallbladder motility. EVIDENCE ACQUISITION: The articles included in the present review were identified using electronic literature searches. The search results were narrowed to data reporting the effects of bile acids and GLPs on gallbladder motility. EVIDENCE SYNTHESIS: Bile acids negate the effect of postprandial cholecystokinin-mediated gallbladder contraction. Two bile acid receptors seem to be involved in this feedback mechanism, the transmembrane Takeda G protein-coupled receptor 5 (TGR5) and the nuclear farnesoid X receptor. Furthermore, activation of TGR5 in enteroendocrine L cells leads to release of GLP-1 and, possibly, GLP-2. Recent findings have pointed to the existence of a bile acid-TGR5-L cell-GLP-2 axis that serves to terminate meal-induced gallbladder contraction and thereby initiate gallbladder refilling. GLP-2 might play a dominant role in this axis by directly relaxing the gallbladder. Moreover, recent findings have suggested GLP-1RA treatment prolongs the refilling phase of the gallbladder. CONCLUSIONS: GLP-2 receptor activation in rodents acutely increases the volume of the gallbladder, which might explain the risk of gallbladder diseases associated with GLP-2RA treatment observed in humans. GLP-1RA-induced prolongation of human gallbladder refilling may explain the gallbladder events observed in GLP-1RA clinical trials.

Ultrasound Assessment of Hepatobiliary and Splenic Changes in Patients With Dengue and Warning Signs During the Acute and Recovery Phases.

OBJECTIVES: To evaluate whether abdominal ultrasound (US) with a gallbladder (GB) contractility study or motor function test can be used as a diagnostic tool in patients with dengue and warning signs in acute and recovery phases. METHODS: Fifty-one individuals in the acute phase of dengue presenting with warning signs (dengue group) and 49 healthy individuals without a history of dengue or hepatobiliary disease (control group) were studied with abdominal US and a GB contractility study. RESULTS: Statistical differences in US measurements of the liver (right lobe, P = .012; left lobe, P = .001) and spleen (P = .008) dimensions, GB wall thickness (P < .001), and the GB emptying fraction (P < .001) were observed in dengue during the acute phase compared with the control group. After 60 days, abdominal US of the dengue group showed a statistical difference in liver (right lobe, P < .001; left lobe, P = .078) and spleen (P < .001) dimensions, GB wall thickness, and the GB emptying fraction (P < .001) compared with the results obtained during the acute phase. Furthermore, a statistical difference in the spleen volume and GB emptying fraction (P < .001) was observed when comparing dengue after clinical recovery and the control group. Abdominal pain in patients with dengue was positively associated with hepatomegaly (P = .031), splenomegaly (P = .008), increased GB wall thickness (P = .016), and a reduced GB emptying fraction (P = .038) during the acute phase and with splenomegaly (P = .001) and a reduced GB emptying fraction (P = .003) after clinical recovery. CONCLUSIONS: Abdominal US with a GB motor function test can be used as a diagnostic tool in patients with dengue during acute and recovery phases.

Update on the Molecular Mechanisms Underlying the Effect of Cholecystokinin and Cholecystokinin-1 Receptor on the Formation of Cholesterol Gallstones.

Cholecystokinin (CCK) is an important neuro-intestinal peptide hormone produced by the enteroendocrine I-cells in the upper part of small intestine. Protein- and fat-enriched food plays an important role in triggering CCK secretion from the intestine. Carbohydrates stimulate only small amounts of CCK release. The CCK-1 receptor (CCK-1R) is largely localized in the gallbladder, sphincter of Oddi, pancreas, small intestine, gastric mucosa, and pyloric sphincter, where it is responsible for CCK to regulate multiple digestive processes including gallbladder contraction, pancreatic secretion, small intestinal transit, and gastric emptying. Accumulated evidence clearly demonstrates that CCK regulates gallbladder and small intestinal motility through CCK-1R signaling cascade and the effect of CCK-1R on small intestinal transit is a physiological response for regulating intestinal cholesterol absorption. Disruption of the Cck or the Cck-1r gene in mice significantly increases the formation of cholesterol gallstones by disrupting gallbladder emptying and biliary cholesterol metabolism, as well as promoting intestinal absorption of cholesterol. Abnormalities in gallbladder motility function in response to exogenously administered CCK are found primarily in patients with cholesterol gallstones. Patients with pigment gallstones display an intermediate degree of gallbladder motility defect without gallbladder inflammation and enlarged fasting gallbladder. Dysfunctional gallbladder contractility has been found under several conditions such as pregnancy, obesity, diabetes, celiac disease, and total parenteral nutrition although gallstones are not observed. The gallbladder-specific CCK-1R-selective agonist may lead to an efficacious novel way for preventing gallstone formation by promoting gallbladder emptying, particularly for pregnant women and subjects with dysfunctional gallbladder motility function such as celiac patients, as well as patients with total parenteral nutrition.

Cholecystokinin secretion is suppressed by glucagon-like peptide-1: clue to the mechanism of the adverse gallbladder events of GLP-1-derived drugs.

OBJECTIVE: Recent randomized and controlled trials of drugs derived from the gut hormone glucagon-like peptide-1 (GLP-1) show that the most frequent adverse symptoms are gastrointestinal, including gallbladder-related side effects such as cholithiasis and cholecystitis. Since the gut hormone cholecystokinin (CCK) stimulates bile secretion and regulates gallbladder motility and emptying, we examined the effect of GLP-1 on the secretion of CCK in normal subjects and patients with type 1 diabetes mellitus. MATERIALS AND METHODS: Plasma was sampled from 10 healthy subjects and 10 patients with diabetes. With plasma glucose concentrations clamped between 6 and 9 nmol/l, GLP-1 or saline was infused for 240 min during and after a meal. The plasma concentrations of CCK were measured with a highly specific radioimmunoassay. RESULTS: Basal plasma concentrations of CCK were similar in the normal subjects and in the diabetes patients. During the meal, the CCK concentrations rose significantly during saline infusion, whereas the GLP-1 infusion suppressed the secretion of CCK significantly in both normal subjects and in the diabetes patients. CONCLUSIONS: The results show that GLP-1 suppresses the secretion of CCK after a meal in normal and diabetic subjects. The suppression attenuates the gallbladder contractility. Our data, therefore, offer an explanation for the increased risk of adverse gallbladder events during treatment with GLP-1-derived drugs.

Effect of prednisolone administration on gallbladder emptying rate and gallbladder bile composition in dogs.

OBJECTIVE To investigate effects of prednisolone administration on gallbladder emptying rate and gallbladder bile composition in dogs. ANIMALS 6 healthy Beagles. PROCEDURES Prednisolone was administered (2 mg/kg, SC, once daily for 2 weeks) to each dog and tapered over 2 weeks. Gallbladder emptying rate and bile composition were evaluated before and after administration of prednisolone for 2 weeks as well as 1 week after cessation of prednisolone administration. RESULTS Gallbladder emptying rate decreased significantly after prednisolone administration (median, 27%; range, 0% to 38%), compared with rate before administration (median, 59%; range, 29% to 68%), but then increased 1 week after cessation of administration (median, 45%; range, 23% to 48%). Gallbladder bile mucin concentration decreased significantly after prednisolone administration (median, 8.8 mg/dL; range, 6.2 to 11.3 mg/dL), compared with concentration before administration (median, 13.1 mg/dL; range, 10.7 to 21.7 mg/dL), but then increased 1 week after cessation of administration (median, 14.3 mg/dL; range, 9.6 to 26.7 mg/dL). Gallbladder taurochenodeoxycholic acid concentration decreased significantly after prednisolone administration (8.1 mmol/L; range, 6.8 to 15.2 mmol/L), compared with concentration before administration (median, 27.2 mmol/L; range, 22.0 to 31.9 mmol/L), but then increased 1 week after cessation of administration (median, 26.4 mmol/L; range, 15.1 to 31.5 mmol/L). CONCLUSIONS AND CLINICAL RELEVANCE A lower gallbladder emptying rate caused by prednisolone administration may be involved in the pathogenesis of gallbladder disease in dogs. Further studies are required to determine the clinical importance of lower gallbladder bile mucin concentrations caused by glucocorticoid administration in the pathogenesis of gallbladder disease in dogs.

Scintigraphic Findings Beyond Ejection Fraction on Hepatobiliary Scintigraphy: Are They Correlated With Chronic Gallbladder Disease?

OBJECTIVE: To determine if classically reported findings associated with chronic cholecystitis on hepatobiliary scintigraphy (HBS), such as delayed small bowel (SB) transit, slow gallbladder (GB) filling, and reversal of the normal GB and SB transit, are associated with a depressed GB ejection fraction (GBEF). The secondary objectives were to determine whether GBEF is correlated with the time of GB filling, time of SB transit, or reversal of normal GB/SB filling sequence. We hypothesize that an association between a depressed GBEF and these classical HBS findings could validate them as surrogate markers for chronic GB disease. PATIENTS AND METHODS: We reviewed all HBS exams over a retrospective 16-month period. Data from 221 patients (mean age, 45.3 ± 15.2 years; 152 female and 69 male subjects) who underwent HBS with GBEF determination for evaluation of chronic symptoms concerning for biliary etiology met inclusion criteria. Classically reported findings for cholecystitis were recorded for each patient. Comparisons were made using t test and Fisher test analysis. RESULTS: Comparing exams with normal and abnormal GBEF values, there were no significant differences based on age, sex, GB fill time, normal versus delayed SB transit, and reversal of normal GB/SB filling sequence. Additionally, we did not see a correlation between the measured GBEF and GB fill time, SB transit time, or reversal of normal GB/SB filling sequence. CONCLUSIONS: Delayed SB transit, slow GB filling time, and reversal of the normal GB and SB filling sequence on HBS imaging are not associated with the measured GBEF and not predictive of chronic GB disease.

Effects of a Gluten-Containing Meal on Gastric Emptying and Gallbladder Contraction.

The ingestion of gluten has been associated with gastrointestinal symptoms even in the absence of detectable immune responses. Little is known about the pathophysiological effects of gluten on the upper gastrointestinal tract. We aimed to assess whether the ingestion of gluten leads to an impairment of the physiological mechanisms of gastric emptying, gallbladder contraction and relaxation. A total of 17 healthy subjects underwent ultrasound evaluation of gastric emptying dynamics and gallbladder contractions at baseline and every 30 min after a standard gluten-containing and gluten-free meal (250 kcal, 70% carbohydrates). The pattern of gastric emptying was similar after a standard meal with or without gluten, but differed in terms of the peak of the antral filling curve, which was wider (mean area 5.69, median 4.70, range 3.71‒9.27 cm² vs. mean 4.89, median 4.57, 2.27‒10.22 cm², p = 0.023) after the gluten-containing meal. The pattern of gallbladder contractions was different after the gluten-free meal (p < 0.05), with higher gallbladder volumes in the late refilling phases. The results of this study show that gluten ingestion exerts objective effects on gastric and gallbladder motility. Although the underlying pathophysiological mechanism remains unknown, these results could account for some of the gluten-related symptoms reported by patients with celiac disease and non-celiac gluten sensitivity.

Effects of liraglutide on gallbladder emptying: A randomized, placebo-controlled trial in adults with overweight or obesity.

AIMS: Treatment with liraglutide 3.0 mg has been associated with gallbladder-related adverse events. To conduct a single-centre, double-blind, 12-week trial comparing the effect of 0.6 mg liraglutide and steady-state liraglutide 3.0 mg with placebo on gallbladder emptying in adults with body mass index (BMI) ≥27 kg/m2 and without diabetes. METHODS: Participants were randomized 1:1 to once-daily subcutaneous liraglutide (n = 26) or placebo (n = 26), starting at 0.6 mg with 0.6-mg weekly increments to 3.0 mg, with nutritional and physical activity counselling. A 600-kcal (23.7 g fat) liquid meal test was performed at baseline, after the first dose and after 12 weeks. The primary endpoint was the 12-week maximum postprandial gallbladder ejection fraction (GBEFmax ), measured over 240 minutes after starting the meal. RESULTS: Baseline characteristics were similar between groups (mean ± SD overall age 47.6 ± 10.0 years, BMI 32.6 ±3.4 kg/m2 , 50% women). Mean 12-week GBEFmax (treatment difference -3.7%, 95% confidence interval [CI] -13.1, 5.7) and area under the GBEF curve in the first 60 minutes (-390% × min, 95% CI -919, 140) did not differ for liraglutide 3.0 mg (n = 23) vs placebo (n = 24). The median (range) time to GBEFmax was 151 (11-240) minutes with liraglutide 3.0 mg and 77 (22-212) minutes with placebo. Similar findings were noted after the first 0.6-mg liraglutide dose. Gastrointestinal disorders, notably nausea and constipation, were the most frequently reported adverse events. CONCLUSIONS: Treatment with liraglutide did not affect the GBEFmax but appeared to prolong the time to GBEFmax .