Incretin therapy for diabetes mellitus type 2

Effects of Tirzepatide vs Semaglutide on β-Cell Function, Insulin Sensitivity, and Glucose Control During a Meal Test

CONTEXT

In a clinical study, tirzepatide, a glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonist (GIP/GLP-1RA), provided superior glycemic control vs the GLP-1RA semaglutide. The physiologic mechanisms are incompletely understood.

OBJECTIVE

This work aimed to evaluate treatment effects by model-based analyses of mixed-meal tolerance test (MMTT) data.

METHODS

A 28-week double-blind, randomized, placebo-controlled trial of patients with type 2 diabetes treated with metformin was conducted at 2 clinical research centers in Germany. Interventions included tirzepatide 15 mg, semaglutide 1 mg, and placebo. Main outcome measures included glycemic control, model-derived β-cell function indices including insulin secretion rate (ISR) at 7.2-mmol/L glucose (ISR7.2), β-cell glucose sensitivity (β-CGS), insulin sensitivity, and estimated hepatic insulin-to-glucagon ratio.

RESULTS

Tirzepatide significantly reduced fasting glucose and MMTT total glucose area under the curve (AUC) vs semaglutide (P < .01). Incremental glucose AUC did not differ significantly between treatments; therefore, greater total glucose AUC reduction with tirzepatide was mainly attributable to greater suppression of fasting glucose. A greater reduction in total ISR AUC was achieved with tirzepatide vs semaglutide (P < .01), in the context of greater improvement in insulin sensitivity with tirzepatide (P < .01). ISR7.2 was significantly increased with tirzepatide vs semaglutide (P < .05), showing improved β-CGS. MMTT-derived β-CGS was increased but not significantly different between treatments. Both treatments reduced fasting glucagon and total glucagon AUC, with glucagon AUC significantly reduced with tirzepatide vs semaglutide (P < .01). The estimated hepatic insulin-to-glucagon ratio did not change substantially with either treatment.

CONCLUSION

These results suggest that the greater glycemic control observed for tirzepatide manifests as improved fasting glucose and glucose excursion control, due to improvements in ISR, insulin sensitivity, and glucagon suppression.

Semaglutide treatment for PRevention Of Toxicity in high-dosE Chemotherapy with autologous haematopoietic stem-cell Transplantation (PROTECT): study protocol for a randomised, double-blind, placebo-controlled, investigator-initiated study

INTRODUCTION

Cancer treatment with high-dose chemotherapy damages the mucosal barrier of the gastrointestinal (GI) tract and is associated with severe toxicity involving mucositis, severe inflammation and organ dysfunction. Currently, there is no effective prophylaxis against this. Glucagon-like peptide 1 (GLP-1), a well-known regulator of blood glucose, has been suggested in mouse studies to possess trophic effects on gut epithelial cells as well as anti-inflammatory properties. In line with this, endogenous GLP-1 levels have been shown to be inversely correlated with toxicities after haematopoietic stem cell transplantation (HSCT) and treatment with a GLP-1 receptor agonist (GLP-1RA) was shown to limit chemotherapy-induced mucositis in rodents. This present study investigates the effects of the GLP-1RA semaglutide on GI mucositis severity score in patients with lymphoma undergoing high-dose chemotherapy followed by autologous (auto) HSCT.

METHODS AND ANALYSIS

This is a randomised, double-blind, placebo-controlled, two-centre investigator-initiated clinical study. Forty adult patients with malignant lymphoma referred for auto-HSCT will be randomised in a 1:1 manner to receive either semaglutide or placebo once-weekly for 8 weeks. This includes a run-in period of 3-4 weeks with semaglutide 0.25 mg prior to high-dose chemotherapy treatment followed by a period of 4-5 weeks with semaglutide 0.5 mg including the 1 week of high-dose chemotherapy treatment. Clinical assessment of endpoint measurements and safety will be performed weekly during treatment and in a follow-up period of 10 weeks. The primary endpoint is GI mucositis severity (mean severity grade (0-II) during week 1-4 after auto-HSCT). Secondary endpoints include C-reactive protein increment, quality of life and safety. Fever, bacteraemia, antibiotic use, weight loss, morphine consumption, duration of hospitalisation, use of parenteral nutrition, change in muscle mass and clinical and laboratory evidence of organ toxicities will also be assessed.

ETHICS AND DISSEMINATION

The study complies with Danish and European Union legislation and is approved by the Danish Medicines Agency, the Danish National Medical Research Ethics Committee (EU CT #2022-502139-20-00) 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 international scientific meetings and in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT06449625.

Exendin-4 affects calcium signalling predominantly during activation and activity of beta cell networks in acute mouse pancreas tissue slices

Tight control of beta cell stimulus-secretion coupling is crucial for maintaining homeostasis of energy-rich nutrients. While glucose serves as a primary regulator of this process, incretins augment beta cell function, partly by enhancing cytosolic [Ca2+] dynamics. However, the details of how precisely they affect beta cell recruitment during activation, their active time, and functional connectivity during plateau activity, and how they influence beta cell deactivation remain to be described. Performing functional multicellular Ca2+ imaging in acute mouse pancreas tissue slices enabled us to systematically assess the effects of the GLP-1 receptor agonist exendin-4 (Ex-4) simultaneously in many coupled beta cells with high resolution. In otherwise substimulatory glucose, Ex-4 was able to recruit approximately a quarter of beta cells into an active state. Costimulation with Ex-4 and stimulatory glucose shortened the activation delays and accelerated beta cell activation dynamics. More specifically, active time increased faster, and the time required to reach half-maximal activation was effectively halved in the presence of Ex-4. Moreover, the active time and regularity of [Ca2+]IC oscillations increased, especially during the first part of beta cell response. In contrast, subsequent addition of Ex-4 to already active cells did not significantly enhance beta cell activity. Network analyses further confirmed increased connectivity during activation and activity in the presence of Ex-4, with hub cell roles remaining rather stable in both control experiments and experiments with Ex-4. Interestingly, Ex-4 demonstrated a biphasic effect on deactivation, slightly prolonging beta cell activity at physiological concentrations and shortening deactivation delays at supraphysiological concentrations. In sum, costimulation by Ex-4 and glucose increases [Ca2+]IC during beta cell activation and activity, indicating that the effect of incretins may, to an important extent, be explained by enhanced [Ca2+]IC signals. During deactivation, previous incretin stimulation does not critically prolong cellular activity, which corroborates their low risk of hypoglycemia.

Diabetes-Related Mechanisms of Action Involved in the Therapeutic Effect of Croton Species: A Systematic Review

Over the years, ethnopharmacological and phytochemical investigations have been conducted to understand the potential effects of the Croton genus on several diseases. It has been revealed that these terpenoid-rich species traditionally used to treat gastrointestinal diseases, heal wounds, and relieve pain have a wide range of therapeutic effects; however, those used to treat diabetes, as well as their action mechanisms, have not been reviewed so far. Therefore, the main objective of this review was to compile all Croton species that have shown pharmacological effects against diabetes and describe their action mechanisms. Through a search of the literature, 17 species with hypoglycemic, antihyperglycemic, antilipidemic, antihypertensive, antioxidant, and anti-inflammatory effects were found. Among the mechanisms by which they exerted these effects were the inhibition of α-glucosidases, the promotion of insulin secretion, and the increase in glucose uptake. Interestingly, it was found that some of them may have antihyperglycemic properties, although there were no ethnopharmacological reports that support their traditional use. Moreover, others only presented studies on their hypoglycemic effect in fasting, so further works are encouraged to describe the mechanisms involved in lowering fasting blood glucose levels, such as hepatic glucose production, especially for C. cajucara, C. cuneatus, C. gratissimus var. gratissimus, C. guatemalensis, and C. membranaceus. It is expected that this review contributes to the plant science knowledge of the genus, and it can be used in future references on the identification and development of new molecules/phytomedicines that help in the treatment of diabetes.

Pathophysiology of type 2 diabetes and the impact of altered metabolic interorgan crosstalk

Diabetes is a complex and multifactorial disease that affects millions of people worldwide, reducing the quality of life significantly, and results in grave consequences for our health care system. In type 2 diabetes (T2D), the lack of β-cell compensatory mechanisms overcoming peripherally developed insulin resistance is a paramount factor leading to disturbed blood glucose levels and lipid metabolism. Impaired β-cell functions and insulin resistance have been studied extensively resulting in a good understanding of these pathways but much less is known about interorgan crosstalk, which we define as signaling between tissues by secreted factors. Besides hormones and organokines, dysregulated blood glucose and long-lasting hyperglycemia in T2D is associated with changes in metabolism with metabolites from different tissues contributing to the development of this disease. Recent data suggest that metabolites, such as lipids including free fatty acids and amino acids, play important roles in the interorgan crosstalk during the development of T2D. In general, metabolic remodeling affects physiological homeostasis and impacts the development of T2D. Hence, we highlight the importance of metabolic interorgan crosstalk in this review to gain enhanced knowledge of the pathophysiology of T2D, which may lead to new therapeutic approaches to treat this disease.

A comprehensive review on the antidiabetic attributes of thiazolidine-4-ones: Synthetic strategies and structure-activity relationships

The thiazolidine-4-one scaffold has recently emerged as a potential pharmacophore having clinical significance for medicinal chemists. This heterocyclic ring has been reported to possess a plethora of biological activities, including antidiabetic activity that has inspired researchers to integrate this core with different pharmacophoric fragments to design novel and effective antidiabetic leads. The antidiabetic activity has been observed due to the ability of the thiazolidine-4-one nucleus to interact with different biological targets, including peroxisome proliferator-activated receptor γ, protein tyrosine phosphatase 1B, aldose reductase, α-glucosidase, and α-amylase. The present review discusses the mode of action of thiazolidine-4-ones through these antidiabetic drug targets. This review attempts to summarize and analyze the recent developments with regard to the antidiabetic potential of thiazolidine-4-ones covering different synthetic strategies, structure-activity relationships, and docking studies reported in the literature. The significance of various structural modifications at C-2, N-3, and C-5 of the thiazolidine-4-one ring has also been discussed in this manuscript. This comprehensive compilation will provide an inevitable scope for the design and development of potential antidiabetic drug candidates having a thiazolidine-4-one core.

Induced Human Regulatory T Cells Express the Glucagon-like Peptide-1 Receptor

The glucagon-like peptide-1 receptor (GLP-1R) plays a key role in metabolism and is an important therapeutic target in diabetes and obesity. Recent studies in experimental animals have shown that certain subsets of T cells express functional GLP-1R, indicating an immune regulatory role of GLP-1. In contrast, less is known about the expression and function of the GLP-1R in human T cells. Here, we provide evidence that activated human T cells express GLP-1R. The expressed GLP-1R was functional, as stimulation with a GLP-1R agonist triggered an increase in intracellular cAMP, which was abrogated by a GLP-1R antagonist. Analysis of CD4⁺ T cells activated under T helper (Th) 1, Th2, Th17 and regulatory T (Treg) cell differentiation conditions indicated that GLP-1R expression was most pronounced in induced Treg (iTreg) cells. Through multimodal single-cell CITE- and TCR-sequencing, we detected GLP-1R expression in 29–34% of the FoxP3⁺CD25⁺CD127^- iTreg cells. GLP-1R⁺ cells showed no difference in their TCR-gene usage nor CDR3 lengths. Finally, we demonstrated the presence of GLP-1R⁺CD4⁺ T cells in skin from patients with allergic contact dermatitis. Taken together, the present data demonstrate that T cell activation triggers the expression of functional GLP-1R in human CD4⁺ T cells. Given the high induction of GLP-1R in human iTreg cells, we hypothesize that GLP-1R⁺ iTreg cells play a key role in the anti-inflammatory effects ascribed to GLP-1R agonists in humans.

Modifying a Hydroxyl Patch in Glucagon-like Peptide 1 Produces Biased Agonists with Unique Signaling Profiles

Glucagon-like peptide-1 (GLP-1) lowers blood glucose by inducing insulin but also has other poorly understood properties. Here, we show that hydroxy amino acids (Thr11, Ser14, Ser17, Ser18) in GLP-1(7-36) act in concert to direct cell signaling. Mutating any single residue to alanine removes one hydroxyl group, thereby reducing receptor affinity and cAMP 10-fold, with Ala11 or Ala14 also reducing β-arrestin-2 10-fold, while Ala17 or Ala18 also increases ERK1/2 phosphorylation 5-fold. Multiple alanine mutations more profoundly bias signaling, differentially silencing or restoring one or more signaling properties. Mutating three serines silences only ERK1/2, the first example of such bias. Mutating all four residues silences β-arrestin-2, ERK1/2, and Ca²⁺ maintains the ligand and receptor at the membrane but still potently stimulates cAMP and insulin secretion in cells and mice. These novel findings indicate that hydrogen bonding cooperatively controls cell signaling and highlight an important regulatory hydroxyl patch in hormones that activate class B G protein-coupled receptors.

Epigenetic modifications at DMRs of imprinting genes in sperm of type 2 diabetic men

High rates of infertility in type 2 diabetic (T2DM) men have led to attempts to understand the mechanisms involved in this process. This condition can be investigated from at least two aspects, namely sperm quality indices and epigenetic alterations. Epigenetics science encompasses the phenomena that can lead to inherited changes independently of the genetics. This study has been performed to test the hypothesis of the relationship between T2DM and the epigenetic profile of the sperm, as well as sperm quality indices. This research included 42 individuals referred to the infertility clinic of Royan Institute, Iran in 2019–2021. The study subjects were assigned to three groups: normozoospermic non-diabetic (control), normozoospermic diabetic (DN) and non-normozoospermic diabetic (D.Non-N). Sperm DNA fragmentation was evaluated using the sperm chromatin structure assay technique. The global methylation level was examined using 5-methyl cytosine antibody and the methylation status in differentially methylated regions of H19, MEST, and SNRPN was assessed using the methylation-sensitive high-resolution melting technique. The results showed that the sperm global methylation in spermatozoa of D.Non-N group was significantly reduced compared with the other two groups (P < 0.05). The MEST and H19 genes were hypomethylated in the spermatozoa of D.Non-N individuals, but the difference level was not significant for MEST. The SNRPN gene was significantly hypermethylated in these individuals (P < 0.05). The results of this study suggest that T2DM alters the methylation profile and epigenetic programming in spermatozoa of humans and that these methylation changes may ultimately influence the fertility status of men with diabetes.

Effects of glucagon-like peptide-1 receptor agonists on secretions of insulin and glucagon and gastric emptying in Japanese individuals with type 2 diabetes: A prospective, observational study

AIMS/INTRODUCTION

Differences in the glucose-lowering mechanisms of glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been noted. Clarifying these differences could facilitate the choice of optimal drugs for individuals with type 2 diabetes and requires investigation in a clinical setting.

MATERIALS AND METHODS

A single-arm, prospective, observational study was conducted to evaluate the effects of various GLP-1RAs on postprandial glucose excursion, secretions of insulin and glucagon as well as on the gastric emptying rate. Participants were subjected to meal tolerance tests before and 2 weeks and 12 weeks after GLP-1RA initiation. Effects on postprandial secretions of glucose-dependent insulinotropic polypeptide (GIP) and apolipoprotein B48 were also investigated.

RESULTS

Eighteen subjects with type 2 diabetes received one of three GLP-1RAs, i.e., lixisenatide, n = 7; liraglutide, n = 6; or dulaglutide, n = 5. While 12-week administration of all of the GLP-1RAs significantly reduced HbA1c, only lixisenatide and liraglutide, but not dulaglutide, significantly reduced body weight. Postprandial glucose elevation was improved by all of the GLP-1RAs. Postprandial insulin levels were suppressed by lixisenatide, while insulin levels were enhanced by liraglutide. Postprandial glucagon levels were suppressed by lixisenatide. The gastric emptying rate was significantly delayed by lixisenatide, while liraglutide and dulaglutide had limited effects on gastric emptying. GIP secretion was suppressed by lixisenatide and liraglutide. Apolipoprotein B48 secretion was suppressed by all of the GLP-1RAs.

CONCLUSIONS

All of the GLP-1RAs were found to improve HbA1c in a 12-week prospective observational study in Japanese individuals with type 2 diabetes. However, differences in the mechanisms of the glucose-lowering effects and body weight reduction were observed.

Incretin based therapies and SGLT-2 inhibitors in kidney transplant recipients with diabetes: A systematic review and meta-analysis

AIMS

We aimed to conduct a systematic review and meta-analysis regarding the use of incretin-based therapies including dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists as well as sodium-glucose co-transporter-2 (SGLT2) inhibitorsin persons with posttransplantation diabetes mellitus (PTDM) so as to assess both their efficacy and safety.

METHODS

We searched for publications on Kidney/Renal Transplantation and DPP-4 inhibitors, GLP-1-receptor agonists and SGLT-2 inhibitors and included every study using these antidiabetics. A p-value < 0.05 was considered statistical significant.

RESULTS

Sixteen studies and 310 individuals with a mean age of 55.98 ± 8.81 years were included in the analysis. Participants received DPP-4 inhibitors in 8 studies, SGLT-2 inhibitors in 6 studies and GLP-1 receptor agonists in 2 studies, with a mean follow-up of 22.03 ± 14.95 weeks. Hemoglobin A1c (HbA1c) reduction was demonstrated in 10 studies (mean +/- standard deviation (MD) = - 0.38%, I² = 45%). MD of HbA1c was -0.3741 and -0.4596 mg/dl for DPP-4 inhibitors and SGLT-2 inhibitors respectively. Nine studies demonstrated differences in fasting plasma glucose (FPG) (MD = - 25,76) and 5 studies in post-prandial glucose (PPG) (MD = - 6.61) before and following treatment. Most studies did not show adverse effects on the glomerular filtration rate (GFR) and hepatic function.

CONCLUSIONS

DPP-4 inhibitors and SGLT2 inhibitors appear both efficacious and safe in renal transplant recipients. More high-quality studies are required to guide therapeutic choices for PTDM.

GRK Inhibition Potentiates Glucagon-Like Peptide-1 Action

The glucagon-like peptide-1 receptor (GLP-1R) is a G-protein-coupled receptor (GPCR) whose activation results in suppression of food intake and improvement of glucose metabolism. Several receptor interacting proteins regulate the signaling of GLP-1R such as G protein-coupled receptor kinases (GRK) and β-arrestins. Here we evaluated the physiological and pharmacological impact of GRK inhibition on GLP-1R activity leveraging small molecule inhibitors of GRK2 and GRK3. We demonstrated that inhibition of GRK: i) inhibited GLP-1-mediated β-arrestin recruitment, ii) enhanced GLP-1-induced insulin secretion in isolated islets and iii) has additive effect with dipeptidyl peptidase 4 in mediating suppression of glucose excursion in mice. These findings highlight the importance of GRK to modulate GLP-1R function in vitro and in vivo. GRK inhibition is a potential therapeutic approach to enhance endogenous and pharmacologically stimulated GLP-1R signaling.

Incretin Hormones and Type 2 Diabetes-Mechanistic Insights and Therapeutic Approaches

Simple Summary

When we ingest a meal, our intestine secretes hormones that are released into the bloodstream. Amongst these hormones are the incretins hormones which stimulate the release of insulin from the pancreas which is essential for the regulation of in particular postprandial glucose concentrations. In patients with type 2 diabetes, the effect of the incretins is diminished. This is thought to contribute importantly to the pathophysiology of the disease. However, in pharmacological amounts, the incretins may still influence insulin secretion and metabolism. Much research has therefore been devoted to the development of incretin-based therapies for type 2 diabetes. These therapies include compounds that strongly resemble the incretins, hereby stimulating their effects as well as inhibitors of the enzymatic degradation of the hormones, thereby increasing the concentration of incretins in the blood. Both therapeutic approaches have been implemented successfully, but research is still ongoing aimed at the development of further optimized therapies.

Abstract

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are secreted from the gut upon nutrient stimulation and regulate postprandial metabolism. These hormones are known as classical incretin hormones and are responsible for a major part of postprandial insulin release. The incretin effect is severely reduced in patients with type 2 diabetes, but it was discovered that administration of GLP-1 agonists was capable of normalizing glucose control in these patients. Over the last decades, much research has been focused on the development of incretin-based therapies for type 2 diabetes. These therapies include incretin receptor agonists and inhibitors of the incretin-degrading enzyme dipeptidyl peptidase-4. Especially the development of diverse GLP-1 receptor agonists has shown immense success, whereas studies of GIP monotherapy in patients with type 2 diabetes have consistently been disappointing. Interestingly, both GIP-GLP-1 co-agonists and GIP receptor antagonists administered in combination with GLP-1R agonists appear to be efficient with respect to both weight loss and control of diabetes, although the molecular mechanisms behind these effects remain unknown. This review describes our current knowledge of the two incretin hormones and the development of incretin-based therapies for treatment of type 2 diabetes.

Tirzepatide: a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) dual agonist in development for the treatment of type 2 diabetes

INTRODUCTION

The glucagon-like peptide-1 (GLP-1) receptor agonists (RA) have increasingly gained prominence in the treatment of type 2 diabetes (T2D) based on their glycemic benefits and favorable body weight and cardiorenal effects. Despite this, continued development of therapeutics with superior efficacy is important to help address persistent challenges in the attainment of metabolic goals in many patients with T2D.

AREAS COVERED

Tirzepatide is an unimolecular dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RA in development for the treatment of T2D. This review summarizes key characteristics of tirzepatide and Phase 1 and Phase 2 clinical trial efficacy and safety results. Additionally, it provides an overview of the ongoing Phase 3 clinical trial program in T2D and briefly summarizes recently initiated studies in patients with obesity and nonalcoholic steatohepatitis. Information in this review comes primarily from published clinical trials, manufacturer's websites, and ClinicalTrials.gov.

EXPERT OPINION

Based on data from Phase 2 trials, tirzepatide has the potential to be the most efficacious therapy in T2D with respect to both glucose and body weight control. Data from the ongoing Phase 3 clinical trial program should start to become available in late 2020 and will determine the future course of this promising therapeutic agent.

Glucagonoma: From skin lesions to the neuroendocrine component (Review)

Glucagonoma is a hormonally active rare pancreatic neuroendocrine tumour causing an excess of glucagon. This is a narrative review based on a multidisciplinary approach of the tumour. Typically associated dermatosis is necrolytic migratory erythema (NME) which is most frequently seen at disease onset. Insulin-dependent diabetes mellitus, depression, diarrhoea, deep vein thrombosis are also identified, as parts of so-called 'D' syndrome. Early diagnosis is life saving due to potential aggressive profile and high risk of liver metastasis. NME as paraneoplastic syndrome may be present for months and even years until adequate recognition and therapy; it is remitted after successful pancreatic surgery. Thus the level of practitioners' awareness is essential. If surgery is not curative, debulking techniques may improve the clinical aspects and even the outcome in association with other procedures such as embolization of hepatic metastasis; ablation of radiofrequency type; medical therapy including chemotherapy, targeted therapy with mTOR inhibitors such as everolimus, PRRT (peptide receptor radiotherapy), and somatostatin analogues (including combinations of medical treatments). Increased awareness of the condition involves multidisciplinary practitioners.

Characterization of on-target adverse events caused by TRK inhibitor therapy

BACKGROUND

The tropomyosin receptor kinase (TRK) pathway controls appetite, balance, and pain sensitivity. While these functions are reflected in the on-target adverse events (AEs) observed with TRK inhibition, these AEs remain under-recognized, and pain upon drug withdrawal has not previously been reported. As TRK inhibitors are approved by multiple regulatory agencies for TRK or ROS1 fusion-positive cancers, characterizing these AEs and corresponding management strategies is crucial.

PATIENTS AND METHODS

Patients with advanced or unresectable solid tumors treated with a TRK inhibitor were retrospectively identified in a search of clinical databases. Among these patients, the frequency, severity, duration, and management outcomes of AEs including weight gain, dizziness or ataxia, and withdrawal pain were characterized.

RESULTS

Ninety-six patients with 15 unique cancer histologies treated with a TRK inhibitor were identified. Weight gain was observed in 53% [95% confidence interval (CI), 43%-62%] of patients and increased with time on TRK inhibition. Pharmacologic intervention, most commonly with glucagon-like peptide 1 analogs or metformin, appeared to result in stabilization or loss of weight. Dizziness, with or without ataxia, was observed in 41% (95% CI, 31%-51%) of patients with a median time to onset of 2 weeks (range, 3 days to 16 months). TRK inhibitor dose reduction was the most effective intervention for dizziness. Pain upon temporary or permanent TRK inhibitor discontinuation was observed in 35% (95% CI, 24%-46%) of patients; this was more common with longer TRK inhibitor use. TRK inhibitor reinitiation was the most effective intervention for withdrawal pain.

CONCLUSIONS

TRK inhibition-related AEs including weight gain, dizziness, and withdrawal pain occur in a substantial proportion of patients receiving TRK inhibitors. This safety profile is unique relative to other anticancer therapies and warrants careful monitoring. These on-target toxicities are manageable with pharmacologic intervention and dose modification.

Labeling and Characterization of Human GLP-1-Secreting L-cells in Primary Ileal Organoid Culture

Glucagon-like peptide-1 (GLP-1) from intestinal L-cells stimulates insulin secretion and reduces appetite after food ingestion, and it is the basis for drugs against type-2 diabetes and obesity. Drugs targeting L- and other enteroendocrine cells are under development, with the aim to mimic endocrine effects of gastric bypass surgery, but they are difficult to develop without human L-cell models. Human ileal organoids, engineered by CRISPR-Cas9, express the fluorescent protein Venus in the proglucagon locus, enabling maintenance of live, identifiable human L-cells in culture. Fluorescence-activated cell sorting (FACS)-purified organoid-derived L-cells, analyzed by RNA sequencing (RNA-seq), express hormones, receptors, and ion channels, largely typical of their murine counterparts. L-cells are electrically active and exhibit membrane depolarization and calcium elevations in response to G-protein-coupled receptor ligands. Organoids secrete hormones in response to glucose and other stimuli. The ability to label and maintain human L-cells in organoid culture opens avenues to explore L-cell function and develop drugs targeting the human enteroendocrine system.

An emerging new concept for the management of type 2 diabetes with a paradigm shift from the glucose-centric to beta cell-centric concept of diabetes - an Asian perspective

INTRODUCTION

Recent advances in anti-diabetic medications and glucose monitoring have led to a paradigm shift in diabetes care. Newer anti-diabetic medications such as DPP-4 inhibitors, GLP-1 receptor agonists (GLP-1RAs), and SGLT2 inhibitors have enabled optimal glycemic control to be achieved without increasing the risk of hypoglycemia and weight gain. Treatment with GLP-1RAs and SGLT2 inhibitors has been demonstrated to improve cardiorenal outcomes, positioning these agents as the mainstay of treatment for patients with type 2 diabetes (T2DM). The development of these newer agents has also prompted a paradigm shift in the concept of T2DM, highlighting the importance of beta cell dysfunction in the pathophysiology of T2DM.

AREAS COVERED

Recent advances in pharmacotherapy for diabetes are summarized with a focus on the role of incretin-based drugs and SGLT2 inhibitors. The importance of a paradigm shift from a glucose-centric to a beta cell-centric concept of T2DM is also discussed, given from an Asian perspective.

EXPERT OPINION

Management of T2DM including lifestyle modification as well as pharmacotherapy should be focused on reducing beta cell workload, to preserve functional beta cell mass. A paradigm shift from a glucose-centric to a beta cell-centric concept of T2DM enhances the implementation of person-centered diabetes care.