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

Targeting the GLP-2 receptor in the management of obesity

Recent advancements in understanding glucagon-like peptide 2 (GLP-2) biology and pharmacology have sparked interest in targeting the GLP-2 receptor (GLP-2R) in the treatment of obesity. GLP-2 is a proglucagon-derived 33-amino acid peptide co-secreted from enteroendocrine L cells along with glucagon-like peptide 1 (GLP-1) and has a range of actions via the GLP-2R, which is particularly expressed in the gastrointestinal tract, the liver, adipose tissue, and the central nervous system (CNS). In humans, GLP-2 evidently induces intestinotrophic effects (i.e., induction of intestinal mucosal proliferation and improved gut barrier function) and promotes mesenteric blood flow. However, GLP-2 does not seem to have appetite or food intake-reducing effects in humans, but its gut barrier-promoting effect may be of interest in the context of obesity. Obesity is associated with reduced gut barrier function, increasing the translocation of proinflammatory gut content to the circulation. This phenomenon constitutes a strong driver of obesity-associated systemic low-grade inflammation, which in turn plays a major role in the development of most obesity-associated complications. Thus, the intestinotrophic and gut barrier-improving effect of GLP-2, which in obese rodent models shows strong anti-inflammatory potential, may, in combination with food intake-reducing strategies, e.g., GLP-1 receptor (GLP-1) agonism, be able to rectify core pathophysiological mechanism of obesity. Here, we provide an overview of GLP-2 physiology in the context of obesity pathophysiology and review the pharmacological potential of GLP-2R activation in the management of obesity and related comorbidities.

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.

How traditional Chinese medicine can prevent recurrence of common bile duct stones after endoscopic retrograde cholangiopancreatography?

Common bile duct stones, as a type of cholelithiasis, are a benign biliary obstruction that easily acute abdominalgia, and Endoscopic Retrograde Cholangiopancreatography (ERCP) is usually the first choice for clinical treatment. However, the increasing recurrence rate of patients after treatment is troubling clinicians and patients. For the prevention of recurrence after ERCP, there is no guideline to provide a clear drug regimen, traditional Chinese medicine however has achieved some result in the treatment of liver-related diseases based on the "gut-liver-bile acid axis". On the basis of this, this article discusses the possibility of traditional Chinese medicine to prevent common bile duct stones (CBDS) after ERCP, and we expect that this article will provide new ideas for the prevention of recurrence of CBDS and for the treatment of cholelithiasis-related diseases with traditional Chinese medicine in future clinical and scientific research.

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.

Long-term outcomes and adverse effects of teduglutide in patients with short bowel syndrome: Highlighting hyperamylasemia and hyperlipasemia

PURPOSE

Short bowel syndrome is a malabsorptive condition that occurs due to surgical removal or a congenital absence of a significant portion of the small intestine. Patients with short bowel syndrome often rely on parenteral support for extended periods or even their entire lives. Teduglutide, a glucagon-like peptide-2 analog, has shown promising results in reducing dependency on parenteral support in these patients by promoting intestinal adaptation and enhancing nutrient absorption. However, the long-term safety of teduglutide remains a concern, particularly with respect to its potential for the development of hyperamylasemia and hyperlipasemia.

METHODS

This study involved patients who received teduglutide from December 2012 to December 2022 at Boston Medical Center. We evaluated outcomes and adverse events, focusing on hyperamylasemia and hyperlipasemia, through chart review.

RESULTS

Thirteen eligible patients were identified who had used teduglutide. Of these, the majority (84.6%) experienced a reduction in parenteral support. A high incidence (72.7%) of nonpathological pancreatic enzyme elevation was observed in patients treated with teduglutide. These elevations were often dose dependent and were not associated with any clinical signs of acute pancreatitis or abnormal imaging findings.

CONCLUSION

This study highlights the need for further investigations into the long-term safety of teduglutide and the importance of closely monitoring amylase and lipase levels in patients undergoing treatment with teduglutide.

The role of glucagon after bariatric/metabolic surgery: much more than an "anti-insulin" hormone

The biological activity of glucagon has recently been proposed to both stimulate hepatic glucose production and also include a paradoxical insulinotropic effect, which could suggest a new role of glucagon in the pathophysiology type 2 diabetes mellitus (T2DM). An insulinotropic role of glucagon has been observed after bariatric/metabolic surgery that is mediated through the GLP-1 receptor on pancreatic beta cells. This effect appears to be modulated by other members of the proglucagon family, playing a key role in the beneficial effects and complications of bariatric/metabolic surgery. Glucagon serves a dual role after sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). In addition to maintaining blood glucose levels, glucagon exhibits an insulinotropic effect, suggesting that glucagon has a more complex function than simply an "anti-insulin hormone".

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.

Risk factors for gallstone disease onset in Japan: Findings from the Shizuoka Study, a population-based cohort study

In the research literature on factors associated with gallstones, large population-based cohort studies are rare. We carried out a study of this type to explore risk factors for the onset of gallstones. This study included Japanese participants aged 40-107 years who were followed prospectively from January 2012 to September 2020 using a dataset composed of two individually linked databases, one containing annual health checkup records and the other containing medical claims for beneficiaries of the National Health Insurance System and the Medical Care System for Elderly in the Latter Stage of Life in Shizuoka Prefecture, Japan. Among the 611,930 participants in the analysis set, 23,843 (3.9%) were diagnosed with gallstones during the observational period (median [max]: 5.68 [7.5] years). Multivariate analysis revealed that risk of gallstone disease was increased by male sex, cerebrovascular disease, any malignancy, dementia, rheumatic disease, chronic pulmonary disease, hypertension, and H. pylori-infected gastritis. These findings provide essential insights into the etiology of cholelithiasis and may contribute to efforts to reduce the incidence of the disease.

GLP-1 and GLP-2 Orchestrate Intestine Integrity, Gut Microbiota, and Immune System Crosstalk

The intestine represents the body’s largest interface between internal organs and external environments except for its nutrient and fluid absorption functions. It has the ability to sense numerous endogenous and exogenous signals from both apical and basolateral surfaces and respond through endocrine and neuronal signaling to maintain metabolic homeostasis and energy expenditure. The intestine also harbours the largest population of microbes that interact with the host to maintain human health and diseases. Furthermore, the gut is known as the largest endocrine gland, secreting over 100 peptides and other molecules that act as signaling molecules to regulate human nutrition and physiology. Among these gut-derived hormones, glucagon-like peptide 1 (GLP-1) and -2 have received the most attention due to their critical role in intestinal function and food absorption as well as their application as key drug targets. In this review, we highlight the current state of the literature that has brought into light the importance of GLP-1 and GLP-2 in orchestrating intestine–microbiota–immune system crosstalk to maintain intestinal barrier integrity, inflammation, and metabolic homeostasis.

Serum cholecystokinin levels can be a predictive factor for difficult cholecystectomy: Decreased cholecystokinin receptor levels

BACKGROUND

Laparoscopic cholecystectomy (LC) is being performed frequently in general surgery practice. Estimation of difficult cholecystectomy is very important to take precautions against complications. Cholecystokinin (CCK) is an important enzyme for gall-bladder motility. CCK receptor is the target for CCK. Fibrosis and emptying problems of gallbladder are related with difficult cholecys-tectomies. We aimed to evaluate the association between plasma CCK and difficult cholecystectomy and try to explain the mechanism.

METHODS

Prospective cross-sectional study was conducted on a group of patients with cholelithiasis Patients who underwent elective cholecystectomy were classified into easy, difficult and very difficult preoperatively using LC difficulty scores. Pre-operative gallbladder empting ratios were measured by ultrasonography. Serum C-reactive protein, and postprandial serum CCK and pancreas polypeptide levels were measured before the operation. Operation data including operation times, adhesion scores, and complications were collected. Tissue CCK receptor levels and tissue fibrosis scores were obtained.

RESULTS

Easy, difficult, and very difficult LC (DLC) groups were consisted of 34, 28, and 8 patients, respectively. Gallbladder emp-tying was 60% in easy LC group, but 15% in very DLC group. Plasma CCK levels in easy group (37.4 pg/ml) were significantly lower than plasma CCK levels of difficult (58.6 pg/ml), and very difficult groups (66.23 pg/ml). Tissue CCK receptor levels of easy, difficult, and very difficult were 372.4, 178.3, and 144.1 ng/100 mg, respectively. Adhesion scores and fibrosis scores of very difficult group were significantly higher than other groups. Operation times were significantly longer in very difficult group. There were two conversions to open in very DLC group (25%).

CONCLUSION

CCK is a reliable parameter for determining the difficulty of LC. Decreased CCK receptor levels with fibrosis of gallbladder are the probably responsible mechanism.

Peptides in the regulation of glucagon secretion

Glucose homeostasis is maintained by the glucoregulatory hormones, glucagon, insulin and somatostatin, secreted from the islets of Langerhans. Glucagon is the body's most important anti-hypoglycemic hormone, mobilizing glucose from glycogen stores in the liver in response to fasting, thus maintaining plasma glucose levels within healthy limits. Glucagon secretion is regulated by both circulating nutrients, hormones and neuronal inputs. Hormones that may regulate glucagon secretion include locally produced insulin and somatostatin, but also urocortin-3, amylin and pancreatic polypeptide, and from outside the pancreas glucagon-like peptide-1 and 2, peptide tyrosine tyrosine and oxyntomodulin, glucose-dependent insulinotropic polypeptide, neurotensin and ghrelin, as well as the hypothalamic hormones arginine-vasopressin and oxytocin, and calcitonin from the thyroid. Each of these hormones have distinct effects, ranging from regulating blood glucose, to regulating appetite, stomach emptying rate and intestinal motility, which makes them interesting targets for treating metabolic diseases. Awareness regarding the potential effects of the hormones on glucagon secretion is important since secretory abnormalities could manifest as hyperglycemia or even lethal hypoglycemia. Here, we review the effects of each individual hormone on glucagon secretion, their interplay, and how treatments aimed at modulating the plasma levels of these hormones may also influence glucagon secretion and glycemic control.