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

Cholecystitis following the initiation of glucagon-like peptide-2 analogue for short bowel syndrome: A case report

Patients with short bowel syndrome (SBS) have a risk for cholelithiasis and cholecystitis, particularly those who have received long-term parenteral nutrition (PN). Teduglutide (Revestive), a glucagon-like peptide-2 (GLP-2) analogue, is the first effective therapy approved for treating patients with SBS via self-subcutaneous injection. It also pharmacologically inhibits gallbladder contraction, which may increase the risks for cholelithiasis and cholecystitis. Here, we report a case of cholecystitis occurring after the introduction of a GLP-2 analogue in a patient with SBS and cholelithiasis. A 16-year-old girl, with a residual intestinal anatomy of 5 cm jejunum and left colon, was referred to our hospital for further treatment of SBS. She underwent jejunocolic anastomosis 2 months later. After that, she received PN for 2.5 years. Teduglutide treatment was initiated to reduce PN dependence. Several asymptomatic gallbladder stones were found during a routine ultrasound examination before drug initiation. On day 31 of teduglutide treatment, right subcostal pain with fever occurred, and the patient was diagnosed with acute cholecystitis. GLP-2 analogue treatment was temporarily discontinued. The patient underwent gallbladder drainage followed by cholecystectomy 3 weeks later. Histopathological findings illustrated mucosal hyperplasia of the gallbladder. Her postoperative course was uneventful, and teduglutide was restarted 2 weeks postoperatively. GLP-2 analogues promote gallbladder refilling and epithelial hyperplasia, which may be a risk factor for cholecystitis in patients with cholelithiasis, as observed in our patient. Based on our experience, patients with SBS and established asymptomatic cholelithiasis may be considered for prophylactic cholecystectomy before the administration of GLP-2 analogues.

Non-genomic actions of steroid hormones on the contractility of non-vascular smooth muscles

Steroid hormones play an important role in physiological processes. The classical pathway of steroid actions is mediated by nuclear receptors, which regulate genes to modify biological processes. Non-genomic pathways of steroid actions are also known, mediated by cell membrane-located seven transmembrane domain receptors. Sex steroids and glucocorticoids have several membrane receptors already identified to mediate their rapid actions. However, mineralocorticoids have no identified membrane receptors, although their rapid actions are also measurable. In non-vascular smooth muscles (bronchial, uterine, gastrointestinal, and urinary), the rapid actions of steroids are mediated through the modification of the intracellular Ca2+ level by various Ca-channels and the cAMP and IP3 system. The non-genomic action can be converted into a genomic one, suggesting that these distinct pathways may interconnect, resulting in convergence between them. Sex steroids mostly relax all the non-vascular smooth muscles, except androgens and progesterone, which contract colonic and urinary bladder smooth muscles, respectively. Corticosteroids also induce relaxation in bronchial and uterine tissues, but their actions on gastrointestinal and urinary bladder smooth muscles have not been investigated yet. Bile acids also contribute to the smooth muscle contractility. Although the therapeutic application of the rapid effects of steroid hormones and their analogues for smooth muscle contractility disorders seems remote, the actions and mechanism discovered so far are promising. Further research is needed to expand our knowledge in this field by using existing experience. One of the greatest challenges is to separate genomic and non-genomic effects, but model molecules are available to start this line of research.

The bile-gut axis and metabolic consequences of cholecystectomy

Cholelithiasis and cholecystitis affect individuals of all ages and are often treated by surgical removal of the gallbladder (cholecystectomy), which is considered a safe, low-risk procedure. Nevertheless, recent findings show that bile and its regulated storage and excretion may have important metabolic effects and that cholecystectomy is associated with several metabolic diseases postoperatively. Bile acids have long been known as emulsifiers essential to the assimilation of lipids and absorption of lipid-soluble vitamins, but more recently, they have also been reported to act as metabolic signaling agents. The nuclear receptor, farnesoid X receptor (FXR), and the G protein-coupled membrane receptor, Takeda G protein-coupled receptor 5 (TGR5), are specific to bile acids. Through activation of these receptors, bile acids control numerous metabolic functions. Cholecystectomy affects the storage and excretion of bile acids, which in turn may influence the activation of FXR and TGR5 and their effects on metabolism including processes leading to metabolic conditions such as metabolic dysfunction-associated steatotic liver disease and metabolic syndrome. Here, with the aim of elucidating mechanisms behind cholecystectomy-associated dysmetabolism, we review studies potentially linking cholecystectomy and bile acid-mediated metabolic effects and discuss possible pathophysiological mechanisms behind cholecystectomy-associated dysmetabolism.

Colesevelam has no acute effect on postprandial GLP-1 levels but abolishes gallbladder refilling

OBJECTIVE

Colesevelam, a bile acid sequestrant approved for the treatment of hypercholesterolaemia, improves glycaemic control in type 2 diabetes. We hypothesised that single-dose colesevelam increases postprandial GLP-1 secretion, thus, reducing postprandial glucose excursions in individuals with type 2 diabetes. Further, we explored the effects of single-dose colesevelam on ultrasonography-assessed postprandial gallbladder motility, paracetamol absorption (proxy for gastric emptying), and circulating factors known to affect gallbladder motility.

METHODS

In a randomised, double-blind, placebo-controlled crossover study, 12 individuals with type 2 diabetes (mean ± SD: age 61 ± 8.8 years; body mass index 29.8 ± 3.0 kg/m2) were subjected to 4 mixed meal tests on separate days; 2 with orally administered colesevelam (3.75 g) and 2 with placebo, with intravenous infusion of the GLP-1 receptor antagonist exendin(9-39)NH2 or saline.

RESULTS

Single-dose colesevelam had no effect on postprandial concentrations of glucose (P = .786), C-peptide (P = .440), or GLP-1 (P = .729), and exendin(9-39)NH2 administration revealed no GLP-1-mediated effects of colesevelam. Colesevelam did not affect gallbladder emptying but abolished gallbladder refilling (P = .001), increased postprandial cholecystokinin (CCK) secretion (P = .010), and decreased postprandial serum concentrations of fibroblast growth factor 19 (FGF19) (P = .035) and bile acids (P = .043).

CONCLUSION

Single-dose colesevelam had no effect on postprandial GLP-1 responses or glucose tolerance but disrupted postprandial gallbladder refilling by increasing CCK secretion and reducing circulating concentrations of FGF19 and bile acids. These findings leave the antidiabetic actions of colesevelam unresolved but provide mechanistic insights into its effect on gallbladder motility.

Liraglutide changes postprandial responses of gut hormones involved in the regulation of gallbladder motility

AIM

Liraglutide treatment is associated with gallbladder-related disorders and has been shown to delay postprandial gallbladder refilling. The gut hormones cholecystokinin (CCK), fibroblast growth factor 19 (FGF19) and glucagon-like peptide 2 (GLP-2), are known to regulate gallbladder motility and may be implicated in gallbladder-related disorders associated with liraglutide treatment.

MATERIALS AND METHODS

In a double-blind, 12-week trial, 52 participants [50% male, age 47.6 ± 10.0 years, body mass index 32.6 ± 3.4 kg/m² (mean ± standard deviation)] with obesity were randomized 1:1 to once-daily subcutaneous liraglutide (escalated from 0.6 mg to 3.0 mg once-daily) or placebo. During liquid meal tests performed at baseline, after the first dose and following 12 weeks of treatment, we evaluated postprandial gallbladder dynamics and plasma responses of CCK, FGF19 and GLP-2.

RESULTS

Liraglutide reduced postprandial FGF19 after the first dose [area under the curve (AUC)_{0-240 min} 24.8 vs. 48.0 min × ng/ml, treatment ratio (TR) (95% confidence interval) 0.52 (0.39; 0.69)] and following 12 weeks of treatment [AUC_{0-240 min} 33.7 vs. 48.5 ng/ml × min, TR 0.69 (0.52; 0.93)]. Liraglutide also reduced postprandial GLP-2 responses (AUC_{0-240 min} 3650 vs. 4894 min × pmol/L, TR 0.75 (0.62; 0.90)] following the first dose as well as after 12 weeks [AUC_{0-240 min} 3760 vs. 4882 min × pmol/L, TR 0.77 (0.60; 0.99)]. Liraglutide increased postprandial responses of CCK after the first dose [AUC_{0-240 min} 762 vs. 670 min × pmol/L; TR 1.14 (0.97; 1.33)] and following 12 weeks of treatment [AUC_{0-240 min} 873 vs. 628 min × pmol/L; TR 1.39 (1.12; 1.73)].

CONCLUSION

Compared with placebo, treatment with liraglutide decreased postprandial FGF19 and GLP-2 concentrations and increased postprandial CCK concentrations, which may explain the delayed postprandial gallbladder refilling observed in individuals with obesity treated with liraglutide.

Association of the gallbladder or biliary diseases with dipeptidyl peptidase 4 inhibitors in patients with type 2 diabetes: a meta-analysis of randomized controlled trials

BACKGROUND

Previous studies have shown inconsistent conclusions regarding the association between incretin-based therapies and the risk of developing gallbladder or biliary diseases. We conducted a meta-analysis to evaluate the risk of gallbladder or biliary diseases associated with dipeptidyl peptidase 4 inhibitors (DPP4i) in patients with type 2 diabetes.

METHODS

The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched (from inception up to March 14, 2022) for published randomized controlled trials (RCTs) that compared DPP4i with placebo or other glucose-lowering drugs in patients with type 2 diabetes. The outcomes of interest were cholecystitis, cholangitis, cholelithiasis, bile duct stones, and biliary colic. Relative risks (RRs) and 95% confidence intervals (CI) were pooled using a random-effects model. Subgroup analyses were performed according to patient age, trial duration, and types of DPP4i.

RESULTS

In total, 97,150 participants from 75 eligible RCTs were included in the meta-analysis. DPP4i were associated with an increased risk of composite of gallbladder or biliary diseases (RR 1.20 [95% CI 1.01-1.42]) and cholecystitis (RR 1.38 [95% CI 1.08-1.75]). Among all included trials, DPP4i showed no association with the following manifestations of gallbladder or biliary diseases: cholelithiasis (RR 1.00 [95% CI 0.76-1.32]), cholangitis (RR 0.81 [95% CI 0.39-1.66]), bile duct stones (RR 1.08 [95% CI 0.57-2.05]), and biliary colic (RR 0.72 [95% CI 0.23-2.25]). Subgroup analyses showed that DPP4i were associated with a higher risk of cholecystitis in older patients (RR 1.37 [95% CI 1.03-1.83]) compared with younger patients (RR 1.08 [95% CI 0.89-2.18]) and in those with a longer duration of drug use (RR 1.43 [95% CI 1.08-1.89]) compared with shorter use (RR 1.23 [95% CI 0.74-2.03]).

CONCLUSIONS

This systematic review and meta-analysis of RCTs found that the use of DPP4i was associated with an increased risk of cholecystitis, especially in patients of advanced age or in those who were exposed to the drugs for a long period of time.

Association between glucagon-like peptide-1 receptor agonists and biliary-related diseases in patients with type 2 diabetes: A nationwide cohort study

STUDY OBJECTIVE

Clinical trials have suggested that glucagon-like peptide-1 receptor agonists (GLP-1RAs) may be associated with a higher risk of biliary-related diseases in patients with type 2 diabetes. Limited real-world studies have examined the comparative biliary safety of GLP-1RAs versus other antihyperglycemic drugs. We aimed to estimate the comparative risk of biliary-related diseases between GLP-1RAs and sodium glucose cotransporter 2 inhibitors (SGLT2is), which are indicated for patients with similar diabetes severity in Taiwan.

DESIGN

Retrospective cohort study.

DATA SOURCE

Taiwan National Health Insurance Database during 2011 to 2018.

PATIENTS

Patients with type 2 diabetes who initiated GLP-1RAs or SGLT2is.

INTERVENTION

GLP-1RAs versus SGLT2is.

MEASUREMENTS AND MAIN RESULTS

We used an on-treatment approach to examine the effect of continuous use and an intention-to-treat approach to assess the effect of initiation of GLP-1RAs versus SGLT2is. We used Coxregression models to estimate the hazard ratios (HRs) and 95% confidenceintervals (CIs) for the composite hospitalized biliary-related diseases, including acute cholecystitis or cholecystectomy, choledocholithiasis, and acute cholangitis, after matching each GLP-1RA initiator to up to 10 SGLT2iinitiators using propensity scores (PSs). Among 78,253 PS-matched patients, GLP-1RA use was associated with a numerically higher risk of biliary-related diseases versus SGLT2i use in the on-treatment analysis, with an HR of 1.20 (95% CI, 0.93-1.56) for the composite outcome, an HR of 1.22 (95% CI, 0.92-1.62) for acute cholecystitis or cholecystectomy, an HR of 1.20 (95% CI, 0.69-2.07) for choledocholithiasis, and an HR of 1.14 (95% CI,0.82-2.42) for acute cholangitis. The HRs were more pronounced in theintention-to-treat analysis (1.27 [95% CI, 1.05-1.53] for the composite outcome, 1.29 [95% CI, 1.04-1.58] foracute cholecystitis or cholecystectomy, 1.74 [95% CI, 1.23-2.46] for choledocholithiasis, and 1.31 [95% CI, 0.89-1.94] for acute cholangitis). The increased risk of the composite outcome associated with GLP-1RAs was more evident in patients aged 〉60 years, women, and 120 days after treatment initiation. Liraglutide, but not dulaglutide, was associated with an elevated risk.

CONCLUSIONS

GLP-1RAs might be associated with an elevated risk of biliary-related diseases compared to SGLT2is in Asian patients with type 2 diabetes.

Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials

IMPORTANCE

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have been widely recommended for glucose control and cardiovascular risk reduction in patients with type 2 diabetes, and more recently, for weight loss. However, the associations of GLP-1 RAs with gallbladder or biliary diseases are controversial.

OBJECTIVE

To evaluate the association of GLP-1 RA treatment with gallbladder and biliary diseases and to explore risk factors for these associations.

DATA SOURCES

MEDLINE/PubMed, EMBASE, Web of Science, and Cochrane Library (inception to June 30, 2021), websites of clinical trial registries (July 10, 2021), and reference lists. There were no language restrictions.

STUDY SELECTION

Randomized clinical trials (RCTs) comparing the use of GLP-1 RA drugs with placebo or with non-GLP-1 RA drugs in adults.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data according to the PRISMA recommendations and assessed the quality of each study with the Cochrane Collaboration risk-of-bias tool. Pooled relative risks (RRs) were calculated using random or fixed-effects models, as appropriate. The quality of evidence for each outcome was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) framework.

MAIN OUTCOMES AND MEASURES

The primary outcome was the composite of gallbladder or biliary diseases. Secondary outcomes were biliary diseases, biliary cancer, cholecystectomy, cholecystitis, and cholelithiasis. Data analyses were performed from August 5, 2021, to September 3, 2021.

RESULTS

A total of 76 RCTs involving 103 371 patients (mean [SD] age, 57.8 (6.2) years; 41 868 [40.5%] women) were included. Among all included trials, randomization to GLP-1 RA treatment was associated with increased risks of gallbladder or biliary diseases (RR, 1.37; 95% CI, 1.23-1.52); specifically, cholelithiasis (RR, 1.27; 95% CI, 1.10-1.47), cholecystitis (RR, 1.36; 95% CI, 1.14-1.62), and biliary disease (RR, 1.55; 95% CI, 1.08-2.22). Use of GLP-1 RAs was also associated with increased risk of gallbladder or biliary diseases in trials for weight loss (n = 13; RR, 2.29; 95% CI, 1.64-3.18) and for type 2 diabetes or other diseases (n = 63; RR, 1.27; 95% CI, 1.14-1.43; P <.001 for interaction). Among all included trials, GLP-1 RA use was associated with higher risks of gallbladder or biliary diseases at higher doses (RR, 1.56; 95% CI, 1.36-1.78) compared with lower doses (RR, 0.99; 95% CI, 0.73-1.33; P  = .006 for interaction) and with longer duration of use (RR, 1.40; 95% CI, 1.26-1.56) compared with shorter duration (RR, 0.79; 95% CI, 0.48-1.31; P  = .03 for interaction).

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis of RCTs found that use of GLP-1 RAs was associated with increased risk of gallbladder or biliary diseases, especially when used at higher doses, for longer durations, and for weight loss.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42021271599.

The current significance and prospects for the use of dual receptor agonism GLP-1/Glucagon

The therapeutic arsenal for treating type 2 diabetes mellitus (T2DM) has been enriched recently with the inclusion of type 1 glucagon-like peptide (GLP-1). GLP-1 receptor agonists (RA) secondarily reduce appetite, decrease gastric emptying, and reduce body weight. This effect has been used to treat overweight/obesity, especially with comorbidities associated with T2DM. However, the first formulations and adverse effects gradually gave way to new formulations with fewer unpleasant effects and a more extended period of action (weekly subcutaneous administration and even oral administration), which improved the acceptance and adherence to the treatment. Therefore, titration of GLP-1RA should be done gradually. Furthermore, when side effects are consistent and intolerable after weeks/months of titration, a lower dose or a combination of antidiabetic therapies should be implemented, avoiding treatment interruption. The effort to produce increasingly powerful molecules with fewer side effects is the driving force behind the pharmaceutical industry. The unimolecular dual agonism GLP-1RA plus glucagon receptor agonism (GRA) represents an updated pharmacological indication for controlling blood glucose levels in treating T2DM and its comorbidities, showing better effects with less adverse impact than mono GLP-1RA. There are currently different proposals in this way by different laboratories. Nevertheless, the experimental results are promising and show that soon, we will have the contribution of new drugs for the treatment of T2DM.

Understanding the place for GLP-1RA therapy: Translating guidelines for treatment of type 2 diabetes into everyday clinical practice and patient selection

Since the first glucagon-like peptide 1 (GLP-1) receptor agonist (GLP-1RA) was approved in 2005 (exenatide twice daily) for type 2 diabetes (T2D), the class has developed with newer compounds having more pronounced effects on glycaemic control and body weight. Also, administration regimes have become more convenient with once weekly injections, and recently an oral administration has become available. Large-scale randomized controlled cardiovascular (CV) outcome trials (CVOTs) have shown that GLP-1RA therapy can reduce the risk of CV disease (CVD) in high-risk individuals with T2D. In addition, GLP-1RAs may have renal benefits driven by new-onset macroalbuminuria, although no effect on hard renal endpoints has been found. Subsequently, the place for GLP-1RA therapy has changed over recent years, with most societies endorsing GLP-1RA therapy in patients with established or high risk of CVD independently of glycaemia. Initiation of GLP-1RA therapy can be complex due to differences in efficacy, side effects and safety profiles as well as administration forms within the class. Implementing guideline recommendations into ideal patient selection may be challenging both in specialty and non-specialty settings. To ensure adequate and proactive use of modern glucose-lowering medications in the treatment of T2D, it is essential to recognize patients with high risk or documented CVD. The present review provides an overview of the efficacy and benefits of the currently available GLP-1RA compounds. Furthermore, we review the results from recent large-scale CVOTs in a clinical context and suggest improving the implementation of GLP-1RA therapy across specialties to improve overall patient selection.

How glucagon-like peptide 1 receptor agonists work

In recent years, glucagon-like peptide 1 receptor agonists (GLP-1RAs) have become central in the treatment of type 2 diabetes (T2D). In addition to their glucose-lowering properties with low risk of hypoglycaemia, GLP-1RAs reduce body weight and show promising results in reducing cardiovascular risk and renal complications in high-risk individuals with T2D. These findings have changed guidelines on T2D management over the last years, and GLP-1RAs are now widely used in overweight patients with T2D as well as in patients with T2D and cardiovascular disease regardless of glycaemic control. The currently available GLP-1RAs have different pharmacokinetic profiles and differ in their ability to improve glycaemia, reduce body weight and in their cardio- and renal protective potentials. Understanding how these agents work, including insights into their pleiotropic effects on T2D pathophysiology, may improve their clinical utilisation and be useful for exploring other indications such as non-alcoholic steatohepatitis and neurodegenerative disorders. In this review, we provide an overview of approved GLP-1RAs, their clinical effects and mode of action, and we offer insights into the potential of GLP-1RAs for other indications than T2D. Finally, we will discuss the emerging data and therapeutic potential of using GLP-1RAs in combinations with other receptor agonists.

Possible dulaglutide-associated cholecystitis with safe continuation post cholecystectomy

Purpose

Possible dulaglutide-induced cholecystitis, with successful resumption of dulaglutide after cholecystectomy, is discussed.

Summary

A 72-year-old White man was started on dulaglutide for outpatient management of type 2 diabetes, in addition to his existing antihyperglycemic regimen of metformin, glipizide, pioglitazone, and insulin glargine. His glycated hemoglobin (HbA_1c) concentration improved from 8.2% to 7.2% with the addition of dulaglutide. Furthermore, the use of dulaglutide did not lead to weight loss. After 16 months of treatment with dulaglutide, he presented to the emergency room with nausea, loss of appetite, and progressive sharp, nonradiating right upper quadrant pain. Based on symptom presentation, laboratory workup, and computed tomography scan results, acute cholecystitis was diagnosed. He underwent a cholecystectomy to remove what was found to be a gangrenous gallbladder. Per documented surgical dictation from the cholecystectomy, the gallbladder was removed, but portions of the biliary tree were left intact. The patient was continued on dulaglutide postoperatively without recurrence of bile stones, biliary tree disease, or abdominal symptoms at 8 months after initial cholecystitis incident.

Conclusion

A male patient with possible dulaglutide-induced cholecystitis was successfully continued on dulaglutide therapy post cholecystectomy without recurrent complications within the biliary tract.

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⁻¹ × min⁻¹), low-dose GLP-2 (1 pmol × kg⁻¹ × min⁻¹), 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⁻², 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.

Gastrointestinal autonomic neuropathy in diabetes

Gastrointestinal autonomic neuropathy represents an important and diverse, but poorly appreciated, manifestation of diabetic autonomic neuropathy that impacts negatively on quality of life. There is no test to assess gastrointestinal autonomic nerve damage directly in humans; cardiovascular autonomic reflex tests are often used as a surrogate, but are suboptimal. Gastrointestinal symptoms are common in diabetes, but usually correlate only weakly with disordered motility. Diabetic gastroparesis, or abnormally delayed gastric emptying, occurs frequently and is the best characterized manifestation of gastrointestinal autonomic neuropathy. There is a bi-directional relationship between postprandial glycaemia and the rate of gastric emptying. However, autonomic neuropathy can affect the function of any gut segment from the esophagus to the anus. Current management options for gastrointestinal autonomic neuropathy are, for the main part, empirical and sub-optimal.

The effect of acute intragastric vs. intravenous alcohol administration on inflammation markers, blood lipids and gallbladder motility in healthy men

Ethanol intake increases plasma concentrations of triglycerides and chronic ethanol use impairs lipid metabolism and causes chronic inflammation. The gut plays an important role in metabolic handling of nutrients, including lipids, and a leaky gut associated with alcohol intake, allowing inflammatory signals to the portal vein, has been proposed to constitute a mechanism by which ethanol induces hepatic inflammation. We compared the effects of enteral and parenteral administration of ethanol on a range of circulating inflammation markers (including soluble CD163, a marker of liver macrophage activation), lipids, cholecystokinin (CCK) and fibroblast growth factor 19 (FGF19) as well as gallbladder volume. On two separate and randomized study days, we subjected healthy men (n = 12) to double-blinded intragastric ethanol infusion (IGEI) and isoethanolemic intravenous ethanol infusion (IVEI). Blood was sampled and ultrasonographic evaluation of gallbladder volume was performed at frequent intervals for 4 h after initiation of ethanol administration on both days. Little or no effects were observed on plasma levels of inflammation markers during IGEI and IVEI, respectively. Circulating levels of total, low-density lipoprotein and high-density lipoprotein cholesterol decreased after ethanol administration independently of the administration form. Triglyceride and very low-density lipoprotein (VLDL) cholesterol concentrations increased more after IGEI compared to IVEI. IVEI had no effect on plasma CCK and caused an increased gallbladder volume whereas IGEI elicited a CCK response (P < 0.0001) without affecting gallbladder volume. Circulating FGF19 concentrations decreased equally in response to both ethanol administration forms. In conclusion, by evaluating a range of circulating inflammation markers during IGEI and IVEI we were not able to detect signs of systemic low-grade inflammation originating from the presence of ethanol in the gut. IVEI increased gallbladder volume whereas IGEI increased plasma CCK (with neutral effect on gallbladder volume), increased plasma VLDL cholesterol and triglyceride concentrations; indicating that the enteral route of administration may influence ethanol's effects on lipid metabolism.

Loss of Glp2r signaling activates hepatic stellate cells and exacerbates diet-induced steatohepatitis in mice

A glucagon-like peptide-2 (GLP-2) analog is used in individuals with intestinal failure who are at risk for liver disease, yet the hepatic actions of GLP-2 are not understood. Treatment of high-fat diet-fed (HFD-fed) mice with GLP-2 did not modify the development of hepatosteatosis or hepatic inflammation. In contrast, Glp2r-/- mice exhibited increased hepatic lipid accumulation, deterioration in glucose tolerance, and upregulation of biomarkers of hepatic inflammation. Both mouse and human liver expressed the canonical GLP-2 receptor (GLP-2R), and hepatic Glp2r expression was upregulated in mice with hepatosteatosis. Cell fractionation localized the Glp2r to hepatic stellate cells (HSCs), and markers of HSC activation and fibrosis were increased in livers of Glp2r-/- mice. Moreover, GLP-2 directly modulated gene expression in isolated HSCs ex vivo. Taken together, these findings define an essential role for the GLP-2R in hepatic adaptation to nutrient excess and unveil a gut hormone-HSC axis, linking GLP-2R signaling to control of HSC activation.

Effects of Liraglutide Compared With Placebo on Events of Acute Gallbladder or Biliary Disease in Patients With Type 2 Diabetes at High Risk for Cardiovascular Events in the LEADER Randomized Trial

OBJECTIVE

To explore gallbladder- and biliary tract-related events reported for the liraglutide and placebo groups in the Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial.

RESEARCH DESIGN AND METHODS

LEADER was an international, randomized, double-blind, controlled cardiovascular (CV) outcomes trial. Participants with type 2 diabetes at high risk for CV events (n = 9,340) were randomized 1:1 to receive either liraglutide (≤1.8 mg daily; n = 4,668) or placebo (n = 4,672), with both groups also receiving standard care (treatment period: 3.5-5 years). Acute gallstone disease was a medical event of special interest. This post hoc analysis categorized captured events of acute gallbladder or biliary disease into four groups: uncomplicated gallbladder stones, complicated gallbladder stones, cholecystitis, and biliary obstruction. Time to first event by treatment group was analyzed using Cox regression.

RESULTS

There was an increased risk of acute gallbladder or biliary disease with liraglutide versus placebo (n = 141 of 4,668 vs. n = 88 of 4,672 patients, respectively; hazard ratio [HR] 1.60; 95% CI 1.23, 2.09; P < 0.001). Similar trends were observed for each of the four categories of gallbladder- or biliary tract-related events. Cholecystectomy was performed more frequently in liraglutide-treated patients (HR 1.56; 95% CI 1.10, 2.20; P = 0.013) but for similar proportions of the patients who experienced gallbladder- or biliary tract-related events (57% with liraglutide vs. 59% with placebo).

CONCLUSIONS

Although LEADER was not specifically designed to assess acute gallbladder or biliary disease, the trial showed an increased risk of gallbladder- or biliary tract-related events with liraglutide versus placebo, which appeared to be consistent across four categories of these events. Further studies should investigate the relevant mechanisms.