Expression of bile acid receptors and transporters along the intestine of patients with type 2 diabetes and controls.

CONTEXT: The enterohepatic circulation of bile acids depends on intestinal absorption by bile acid transporters and activation of bile acid receptors, which stimulates secretion of hormones regulating glucose and lipid metabolism and appetite. Distribution of bile acid transporters and receptors in the human gut and their potential involvement in type 2 diabetes (T2D) pathophysiology remain unknown. OBJECTIVE: We explored the expression of genes involved in bile acid metabolism throughout the intestines of patients with T2D and matched healthy controls. METHODS: Intestinal mucosa biopsies sampled along the intestinal tract in 12 individuals with T2D and 12 healthy controls were subjected to mRNA sequencing. We report expression profiles of apical sodium-dependent bile acid transporter (ASBT), organic solute transporter (OST) α/ß, farnesoid X receptor (FXR), Takeda G receptor 5 (TGR5), fibroblast growth factor 19 (FGF19) and FGF receptor 4 (FGFR4). RESULTS: Expression of ASBT and OSTα/ß was evident in the duodenum of both groups with increasing levels through the small intestine, and no (ASBT) or decreasing levels (OSTα/ß) through the large intestine. The FXR expression pattern followed that of OSTα/ß whereas FGFR4 were evenly expressed through the intestines. Negligible levels of TGR5 and FGF19 were evident. Patients with T2D exhibited lower levels of FGF19, FXR, ASBT and OSTα/ß mRNAs compared with healthy controls, although the differences were not statistically significant after adjusting for multiple testing. CONCLUSIONS: We demonstrate distinct expression patterns of bile acid transporters and receptors through the intestinal tract with signs of reduced ASBT, OSTα/ß, FXR and FGF19 mRNAs in T2D.

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.

The Body weight Reducing Effects of Tirzepatide in People with and without Type 2 Diabetes: A Review on Efficacy and Adverse Effects.

Obesity is becoming more frequent and has several negative health impacts. Recent advances in weight management strategies have primarily resided in pharmaceutical treatments, and the glucagon-like peptide-1 (GLP-1) receptor agonists have shown great potential in terms of body weight reduction in addition to improving glycemic control in patients with type 2 diabetes (T2D). Recently, the dual GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide has been developed. Tirzepatide has shown strong effects on glycated hemoglobin (HbA1C) levels in several clinical trials including participants with T2D (SURPASS program). In addition to its lowering effect on HbA1C, tirzepatide leads to substantial reductions in body weight, and a series of clinical trials (SURMOUNT program) have investigated the effects on body weight as the primary outcome. In these two trial programs, tirzepatide in doses of 5 mg to 15 mg administered subcutaneously once weekly resulted in body weight reduction of up to 15% in participants with T2D and up to 21% in participants without T2D, despite comparable baseline bodyweight. Across the two trial programs, adverse effects were mainly gastrointestinal (nausea, diarrhea, and vomiting) occurring with similar incidences of vomiting and lower incidences of diarrhea and nausea in trial participants with T2D compared to trials participants without T2D. Overall, discontinuation due to adverse events occurred in 3-7% of participants with no major differences between individuals with and without T2D. The higher weight-reducing efficacy of tirzepatide in trial participants without T2D is currently unexplained and may be partly reflected in dissimilarities in frequencies of gastrointestinal adverse events. The weight reducing effects of tirzepatide hold great promise for weight management in obese patients regardless of the presence of T2D.

Elucidating the glucose-lowering effect of the bile acid sequestrant sevelamer.

AIM: Bile acid sequestrants are cholesterol-lowering drugs, which also improve glycaemic control in people with type 2 diabetes. The mechanism behind the glucose-lowering effect is unknown but has been proposed to be mediated by increased glucagon-like peptide-1 (GLP-1) secretion. Here, we investigated the glucose-lowering effects of sevelamer including any contribution from GLP-1 in people with type 2 diabetes. MATERIALS AND METHODS: In a randomized, double-blind, placebo-controlled, crossover study, 15 people with type 2 diabetes on metformin monotherapy underwent two 17-day treatment periods with the bile acid sequestrant sevelamer and placebo, respectively, in a randomized order and with an interposed wash-out period of minimum 6 weeks. On days 15 and 17 of each treatment period, participants underwent experimental days with 4-h liquid meal tests and application of concomitant infusion of exendin(9-39)NH2 or saline. RESULTS: Compared with placebo, sevelamer improved insulin sensitivity (assessed by homeostatic model assessment of insulin resistance) and beta-cell sensitivity to glucose and lowered fasting and postprandial plasma glucose concentrations. In both treatment periods, exendin(9-39)NH2 increased postprandial glucose excursions compared with saline but without absolute or relative difference between the two treatment periods. In contrast, exendin(9-39)NH2 abolished the sevelamer-induced improvement in beta-cell glucose sensitivity. CONCLUSIONS: The bile acid sequestrant sevelamer improved insulin sensitivity and beta-cell sensitivity to glucose, but using the GLP-1 receptor antagonist exendin(9-39)NH2 we were not able to detect a GLP-1-mediated glucose-lowering effect of sevelamer in individuals with type 2 diabetes. Nevertheless, the sevelamer-induced improvement of beta-cell sensitivity to glucose was shown to be GLP-1-dependent.

Effects of levothyroxine substitution therapy on hunger and food intake in individuals with hypothyroidism.

Context: In individuals with hypothyroidism and overweight, levothyroxine substitution therapy is often expected to cause weight loss due to its effect on resting energy expenditure. However, despite levothyroxine-induced enhancement of resting energy expenditure, fat mass loss is rarely seen after levothyroxine substitution therapy. The mechanism behind this conundrum is unknown. Aim: The aim of the study was to assess the effect of levothyroxine therapy on hunger sensations and ad libitum food intake in individuals with hypothyroidism. Design and setting: Prospective cohort study of 18 newly diagnosed hypothyroid women (thyroid-stimulating hormone (TSH) >10 mU/L). Participants were investigated at diagnosis, after normalization of TSH (<4.0 mU/L), and after 6 months of successful treatment. Eighteen age and body mass index-matched healthy controls were also included. Intervention: Hypothyroid individuals were treated with levothyroxine according to European Thyroid Association guidelines. Main outcomes: Changes in hunger sensation were assessed using visual analog scales (cm) before and during a standardized mixed meal test, and food intake was measured during a subsequent ad libitum meal (g). Results: After 6 months of levothyroxine therapy, mean resting energy expenditure was increased by 144 kcal/day (10%) (P < 0.001). Weight loss was comprised of 0.8 kg fat-free mass while fat mass remained unchanged. Fasting hunger sensation increased from a mean of 4.5 (s.d. 2.2) cm to 5.5 (s.d. 2.2) cm (P = 0.047). The numerical increase in ad libitum meal intake did not reach statistical significance. Conclusion: Our data suggest that levothyroxine-induced hunger may be a culprit in the lack of fat mass loss from levothyroxine therapy.

Effects of DPP-4 inhibitors, GLP-1 receptor agonists, SGLT-2 inhibitors and sulphonylureas on mortality, cardiovascular and renal outcomes in type 2 diabetes: A network meta-analyses-driven approach.

AIMS: The aim of our meta-analyses was to compare the effects of glucose-lowering drugs on mortality, cardiovascular and renal endpoints for a range of type 2 diabetes (T2D) subgroups defined by their specific cardiovascular risk profile. METHODS: Meta-analyses comparing drugs within the classes of GLP-1RAs and SGLT-2 inhibitors were performed and compared to sulphonylureas and DPP-4 inhibitors with available cardiovascular outcome trials. The comparison between the different classes of glucose-lowering drugs included analyses of T2D populations with low risk and high risk for cardiovascular disease including populations with established cardiovascular disease and/or kidney disease. Outcomes included mortality, major cardiovascular adverse events (MACE), hospitalisation for heart failure (HHF) and a composite renal endpoint as applied in the underlying clinical trials. RESULTS: SGLT-2 inhibitors and GLP-1RAs showed beneficial effects on mortality and MACE compared to the classes of DPP-4 inhibitors and sulphonylureas. SGLT-2 inhibitors were shown to be the most effective treatment in terms of HHF and kidney disease. Metformin was used as background therapy for the vast majority of participants in all included studies. Overall, the absolute effects of SGLT-2 inhibitors and GLP-1RAs on these important outcomes were evident for patients with established or at high risk for cardiovascular disease but limited for the low-risk subgroup. CONCLUSIONS: The findings from our analyses substantiate the relevance of treatment with SGLT-2 inhibitors or GLP-1RAs as an add-on to metformin in patients with T2D and a high risk for cardiovascular disease, and furthermore, support the recommendation for SGLT-2 inhibitor treatment in patients with T2D and heart failure or established kidney disease.

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 [AUC0-240 min 33.7 vs. 48.5 ng/ml × min, TR 0.69 (0.52; 0.93)]. Liraglutide also reduced postprandial GLP-2 responses (AUC0-240 min 3650 vs. 4894 min × pmol/L, TR 0.75 (0.62; 0.90)] following the first dose as well as after 12 weeks [AUC0-240 min 3760 vs. 4882 min × pmol/L, TR 0.77 (0.60; 0.99)]. Liraglutide increased postprandial responses of CCK after the first dose [AUC0-240 min 762 vs. 670 min × pmol/L; TR 1.14 (0.97; 1.33)] and following 12 weeks of treatment [AUC0-240 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.

Safety and efficacy of liraglutide versus colesevelam for the treatment of bile acid diarrhoea: a randomised, double-blind, active-comparator, non-inferiority clinical trial.

BACKGROUND: Bile acid diarrhoea is an underdiagnosed disease estimated to affect 1-2% of the general population. Case reports indicate that the glucagon-like peptide 1 receptor agonist liraglutide might be an effective treatment for bile acid diarrhoea. We aimed to investigate the safety and efficacy of liraglutide for the treatment of bile acid diarrhoea. METHODS: We conducted a randomised, double-blind, active-comparator, double-dummy, non-inferiority clinical trial at the Center for Clinical Metabolic Research at Copenhagen University Hospital-Herlev and Gentofte, Hellerup, Denmark. Patients aged 18-75 years with 75selenium-homotaurocholic acid test (SeHCAT)-verified moderate-to-severe primary bile acid diarrhoea were randomly assigned (1:1) to receive liraglutide (one daily subcutaneous injection uptitrated from 0·6-1·8 mg per day over 3 weeks) or colesevelam (three capsules of 625 mg twice daily), the standard of care, for 6 weeks following one run-in week with no treatment. The primary endpoint was the proportion of participants experiencing a reduction in daily stool frequency of 25% or greater after 6 weeks. Data from all participants were included in the analysis of the primary outcome. The non-inferiority limit was set to 15% in favour of colesevelam. This trial is registered with EudraCT (2018-003575-34) and is completed. FINDINGS: Between April 1, 2019, and Jan 31, 2021, 52 patients were enrolled; 26 were assigned to liraglutide and 26 to colesevelam. 20 (77%) of 26 participants on liraglutide and 13 (50%) of 26 on colesevelam experienced a 25% or greater reduction in stool frequency, corresponding to a significant risk difference of -27% in favour of liraglutide (one-sided 95% CI -100 to -6). Liraglutide was therefore superior to colesevelam in reducing daily stool frequency. Mild nausea with a duration of 10-21 days was reported by six participants in the liraglutide group and by one participant in the colesevelam group. No other adverse events were reported. INTERPRETATION: The superiority of liraglutide compared with colesevelam in reducing stool frequency suggests consideration of liraglutide as a potential new treatment modality for bile acid diarrhoea, although larger confirmatory trials powered for superiority are warranted. FUNDING: Novo Nordisk, Novo Nordisk Foundation, Foundation for the Advancement of Medical Science under The A.P. Møller and Chastine Mc-Kinney Møller Foundation.

Protocol for a randomised, double-blinded, placebo-controlled, double-dummy 6-week clinical trial comparing the treatment effects of the glucagon-like peptide 1 receptor agonist liraglutide versus the bile acid sequestrant colesevelam on bile acid malabsorption.

INTRODUCTION: Bile acid malabsorption (BAM) is a socially debilitating disease characterised by high stool frequency and urgency caused by a spillover of bile acids into the colon. Bile acid sequestrants (BASs) have limited therapeutic effect but represent the only available treatment option. Cases reporting total remission of BAM-related symptoms after treatment with liraglutide, a glucagon-like peptide 1 analogue, prompted us to design a clinical trial investigating the therapeutic effect of this compound in patients with BAM. METHODS AND ANALYSIS: Fifty adult individuals with moderate or severe BAM as assessed by the 75selenium-homotaurocholic acid test (SeHCAT) will, after a run-in period of 10 days with no BAM treatment, be randomised to either treatment with the BAS colesevelam or liraglutide (double blinded) for 6 weeks. Daily symptom diaries and questionnaires will be filled in. Blood and faecal samples will be collected and SeHCAT will be performed at baseline, after week 3 and at end of trial. The primary endpoint is change in daily stool frequency. Secondary endpoints include changes from baseline in questionnaires, biochemistry, SeHCAT and faecal bile acid content and microbial composition. ETHICS AND DISSEMINATION: The study complies with Danish and European Union legislation and is approved by the Danish Medicines Agency, the Regional Scientific Ethics Committee of the Capital Region of Denmark and the Danish Data Protection Agency. The study is monitored by the Capital Region of Denmark's good clinical practice unit. All results, positive, negative and inconclusive, will be disseminated at national and/or international scientific meetings and in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: EudraCA: 2018-003575-34; Pre-results.

Clinical pharmacology of imeglimin for the treatment of type 2 diabetes.

INTRODUCTION: With the rising prevalence of type 2 diabetes (T2D), there is a substantial interest in novel, glucose-lowering drugs that may complement existing treatment options. Imeglimin is an oral antidiabetic agent currently in clinical development. AREAS COVERED: This review is based on a literature search using PubMed and Embase including all published manuscripts and presentations concerning imeglimin. Supplementary information was retrieved from the manufacturer's official webpage. Preclinical and clinical data are summarized with a focus on mechanisms of action as well as clinical efficacy and safety in T2D. EXPERT OPINION: Imeglimin's mode of action seems to be improved mitochondrial function in pancreatic beta cells leading to improved insulin secretion and lowering of plasma glucose levels. In clinical trials of up to 24 weeks, imeglimin in doses of 1,000-1,500 mg twice daily conferred modest reductions in glycates hemoglobin A1c of 6-11 mmol/mol (0.5-1.0%) (placebo-adjusted) as a monotherapy and 7 mmol/mol (0.6%) as an add-on therapy to metformin or sitagliptin in patients with T2D. Reported adverse effects were mainly gastrointestinal discomfort. The position of imeglimin among other pharmacotherapies in the treatment of T2D will be determined based on future studies more clearly outlining the safety and long-term cardiovascular effects. ABBREVIATIONS: AUC: area under the curve; BID: twice daily; DPP-4: dipeptidyl peptidase 4; GLP-1R: glucagon-like peptide-1 receptor; HbA1c: glycated hemoglobin A1c; HFHSD: high-fat high-sucrose diet; OAD: oral antidiabetic; OD: once daily; OGTT: oral glucose tolerance test; PPAR-γ: peroxisome proliferator-activated receptor gamma; PTP: permeability transition pore; SGLT-2: sodium-glucose transport protein 2; STZ: streptozotocin; T2D: type 2 diabetes.

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.

Changes in oxidative nucleic acid modifications and inflammation following one-week treatment with the bile acid sequestrant sevelamer: Two randomised, placebo-controlled trials.

AIMS: Sevelamer has been reported to have anti-oxidative and anti-inflammatory effects as well as effects on glycaemic control and plasma lipids. The aim of this study was to determine the effects of one-week treatment with sevelamer on oxidative nucleic acid modifications and inflammation markers. METHODS: Two double-blinded studies including 30 patients with type 2 diabetes (T2D) and 20 healthy individuals were conducted. Participants were randomised to one week of treatment with sevelamer (1600 mg three times daily) or placebo. RNA and DNA oxidation, measured by urinary excretion of 8-oxo-7,8-dihydroguanosine(8-oxoGuo) and (8-oxo-7,8-dihydro-2'-deoxyguanosine(8-oxodG), and markers of inflammation were determined before and after the intervention. RESULTS: In patients with T2D there was no significant placebo-corrected reduction in 8-oxoGuo or 8-oxodG. However, a reduction in 8-oxoGuo was observed within the group treated with sevelamer (∆8-oxoGuo/creatinine (median[IQR]): -0.04 [-0.24; 0.01] nmol/mmol, p = 0.02). A sevelamer-mediated reduction in interleukin-2 (p = 0.04) and a trend towards reduction in interleukin-6 (p = 0.053) were found in patients with T2D. CONCLUSIONS: This study reveals a potential effect of sevelamer treatment on inflammation and possible oxidative RNA modifications. The potential protective effects of sevelamer in terms of cardiovascular disease in patients with T2D need further investigation.

Gluco-Metabolic Effects of Pharmacotherapy-Induced Modulation of Bile Acid Physiology.

CONTEXT: The discovery and characterization of the bile acid specific receptors farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5) have facilitated a wealth of research focusing on the link between bile acid physiology and glucose metabolism. Modulation of FXR and TGR5 activation have been demonstrated to affect the secretion of glucagon-like peptide 1, insulin, and glucagon as well as energy expenditure and gut microbiota composition, with potential beneficial effects on glucose metabolism. EVIDENCE ACQUISITION: A search strategy based on literature searches in on PubMed with various combinations of the key words FXR, TGR5, agonist, apical sodium-dependent bile acid transporter (ASBT), bile acid sequestrant, metformin, and glucose metabolism has been applied to obtain material for the present review. Furthermore, manual searches including scanning of reference lists in relevant papers and conference proceedings have been performed. EVIDENCE SYNTHESIS: This review provides an outline of the link between bile acid and glucose metabolism, with a special focus on the gluco-metabolic impact of treatment modalities with modulating effects on bile acid physiology; including FXR agonists, TGR5 agonists, ASBT inhibitors, bile acid sequestrants, and metformin. CONCLUSIONS: Any potential beneficial gluco-metabolic effects of FXR agonists remain to be established, whereas the clinical relevance of TGR5-based treatment modalities seems limited because of substantial safety concerns of TGR5 agonists observed in animal models. The glucose-lowering effects of ASBT inhibitors, bile acid sequestrants, and metformin are at least partly mediated by modulation of bile acid circulation, which might allow an optimization of these bile acid-modulating treatment modalities. (J Clin Endocrinol Metab XX: 00-00, 2019).

The efficacy and safety of exenatide once weekly in patients with type 2 diabetes.

INTRODUCTION: Exenatide once weekly (QW) is a glucagon-like peptide 1 receptor agonist (GLP-1RA) that was approved in 2012 in Europe and the U.S.A. for the treatment of type 2 diabetes (T2D). Areas covered: This review provides an overview of the safety and efficacy of exenatide QW for the treatment of T2D and evaluates the benefit-risk ratio compared to other available long-acting GLP-1RAs. In addition, the authors provide an outline of the novel formulations and delivery methods of exenatide. Expert opinion: Exenatide QW is an efficacious and safe treatment for T2D. However, head-to-head trials have demonstrated exenatide QW to be inferior to liraglutide and semaglutide with respect to effects on fasting plasma glucose, glycated hemoglobin A1c, and bodyweight. In addition, exenatide QW appears inferior to liraglutide and semaglutide in terms of cardiovascular risk reduction. Currently, the overall risk-benefit profiles for the range of GLP-1RAs point to liraglutide and semaglutide as first-choice for the management of T2D, which has been confirmed by a recently published consensus report on the treatment of T2D from the American Diabetes Association and the European Association for the Study of Diabetes. The pricing of exenatide QW will most likely be a key determinant for its place in the future management of T2D.

Preclinical discovery and development of colesevelam for the treatment of type 2 diabetes.

Introduction: Type 2 diabetes (T2D) is a major global health challenge associated with increased cardiovascular morbidity and mortality. Intervention strategies managing multiple risk factors (hyperglycemia, hypertension and dyslipidemia) in patients with T2D can reduce the risk of cardiovascular disease by ~50%. Areas covered: Herein, the authors provide an update on the development and clinical potential of colesevelam as a glucose-lowering drug in T2D. Furthermore, they outline the pharmacokinetics, pharmacodynamics, and the clinical efficacy and safety data from the studies carried out to obtain market authorization for colesevelam. Expert opinion: Four phase III clinical trials provide evidence that colesevelam, as a monotherapy and add-on to various background glucose-lowering treatments, confers placebo-corrected reductions in HbA1c of ~5 mmol/mol. In addition, colesevelam reduces low-density lipoprotein (LDL) cholesterol and total cholesterol. Some antidiabetic agents seem superior to colesevelam in terms of clinical efficiency (HbA1c lowering), tolerability/convenience, and price. Nonetheless, colesevelam offers a clinically relevant combination of HbA1c- and LDL-lowering that in selected patients could be relevant as add-on treatment to other glucose-lowering drugs and a statin. Potential patients include those with renal impairment, and patients that are close to reaching their lipid and glycemic treatment goals but need further LDL and HbA1c reductions.

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 .

[Metformin is a possible glucagon-like peptide 1 stimulator].

Metformin is an oral anti-hyperglycaemic drug used as first-line treatment of Type 2 diabetes. It is more effective when administered orally than when administered intravenously, and metformin formulations, which prolong the time residing in the gut are the most potent. This indicates that the intestine plays an essential role in metformin's mode of action. Metformin also increases plasma concentrations of the glucose-lowering gut incretin hormone glucagon-like peptide-1 (GLP-1). This metformin-induced GLP-1 increment may constitute an important link between the gut and the glucose-lowering effect of metformin.

Glucose-lowering effects and mechanisms of the bile acid-sequestering resin sevelamer.

AIMS: Sevelamer, a non-absorbable amine-based resin used for treatment of hyperphosphataemia, has been demonstrated to have a marked bile acid-binding potential alongside beneficial effects on lipid and glucose metabolism. The aim of this study was to investigate the glucose-lowering effect and mechanism(s) of sevelamer in patients with type 2 diabetes. MATERIALS AND METHODS: In this double-blinded randomized controlled trial, we randomized 30 patients with type 2 diabetes to sevelamer (n = 20) or placebo (n = 10). Participants were subjected to standardized 4-hour liquid meal tests at baseline and after 7 days of treatment. The main outcome measure was plasma glucagon-like peptide-1 excursions as measured by area under the curve. In addition, blood was sampled for measurements of glucose, lipids, glucose-dependent insulinotropic polypeptide, C-peptide, glucagon, fibroblast growth factor-19, cholecystokinin and bile acids. Assessments of gastric emptying, resting energy expenditure and gut microbiota composition were performed. RESULTS: Sevelamer elicited a significant placebo-corrected reduction in plasma glucose with concomitant reduced fibroblast growth factor-19 concentrations, increased de novo synthesis of bile acids, a shift towards a more hydrophilic bile acid pool and increased lipogenesis. No glucagon-like peptide-1-mediated effects on insulin, glucagon or gastric emptying were evident, which points to a limited contribution of this incretin hormone to the glucose-lowering effect of sevelamer. Furthermore, no sevelamer-mediated effects on gut microbiota composition or resting energy expenditure were observed. CONCLUSIONS: Sevelamer reduced plasma glucose concentrations in patients with type 2 diabetes by mechanisms that seemed to involve decreased intestinal and hepatic bile acid-mediated farnesoid X receptor activation.

The bile acid-sequestering resin sevelamer eliminates the acute GLP-1 stimulatory effect of endogenously released bile acids in patients with type 2 diabetes.

AIMS: Discovery of the specific bile acid receptors farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5) in enteroendocrine L cells has prompted research focusing on the impact of bile acids on glucagon-like peptide-1 (GLP-1) secretion and glucose metabolism. The aim of the present study was to assess the GLP-1 secretory and gluco-metabolic effects of endogenously released bile, with and without concomitant administration of the bile acid-sequestering resin, sevelamer, in patients with type 2 diabetes. MATERIALS AND METHODS: We performed a randomized, placebo-controlled, double-blinded cross-over study including 15 metformin-treated patients with type 2 diabetes. During 4 experimental study days, either sevelamer 3200 mg or placebo in combination with intravenous infusion of cholecystokinin (CCK) (0.4 pmol sulfated CCK-8/kg/min) or saline was administered in randomized order. The primary endpoint was plasma GLP-1 excursions as measured by incremental area under the curve. Secondary endpoints included plasma responses of glucose, triglycerides, insulin, CCK, fibroblast growth factor-19 and 7α-hydroxy-4-cholesten-3-one (C4). In addition, gallbladder dynamics, gastric emptying, resting energy expenditure, appetite and ad libitum food intake were assessed. RESULTS: CCK-mediated gallbladder emptying was demonstrated to elicit a significant induction of GLP-1 secretion compared to saline, whereas concomitant single-dose administration of the bile acid sequestrant sevelamer was shown to eliminate the acute bile acid-induced increase in plasma GLP-1 excursions. CONCLUSIONS: Single-dose administration of sevelamer eliminated bile acid-mediated GLP-1 secretion in patients with type 2 diabetes, which could be explained by reduced bile acid stimulation of the basolaterally localized TGR5 on enteroendocrine L cells.