The role of incretin receptor agonists in the treatment of obesity.

INTRODRODUCTION: Obesity and its associated metabolic conditions have become a significant global health problem in recent years, with many people living with obesity fulfilling criteria for pharmacological treatment. The development of the glucagon-like peptide-1 receptor agonists for chronic weight management has triggered new interest in the incretins and other hormones as targets for obesity, and investigations into dual and triple co-agonists. METHODS: The objective of this narrative review was to summarize the available data on approved and emerging incretin-based agents for the treatment of obesity. RESULTS: In clinical trials of currently available agents in people with overweight or obesity, weight loss of between 6% and 21% of baseline body weight has been observed, with between 23% and 94% of participants achieving 10% or higher weight loss, depending on the study and the agent used. Favourable outcomes have also been seen with regard to cardiovascular risk and outcomes, diabetes prevention, metabolic dysfunction-associated steatotic liver disease/steatohepatitis and prevention of weight regain after metabolic surgery. Limitations associated with these agents include high costs, the potential for weight regain once treatment is stopped, the potential loss of lean body mass and gastrointestinal adverse events; potential issues with respect to gallbladder and biliary diseases require further investigation. CONCLUSIONS: Many dual and triple co-agonists are still in development, and more data are needed to assess the efficacy, safety and tolerability of these emerging therapies versus the established incretin-based therapies; however, data are promising, and further results are eagerly awaited.

The association of chronic complications with time in tight range and time in range in people with type 1 diabetes: a retrospective cross-sectional real-world study.

AIMS/HYPOTHESIS: The aim of this study was to evaluate the association of chronic complications with time in tight range (TITR: 3.9-7.8 mmol/l) and time in range (TIR: 3.9-10.0 mmol/l) in people with type 1 diabetes. METHODS: The prevalence of microvascular complications (diabetic retinopathy, diabetic nephropathy and diabetic peripheral neuropathy [DPN]) and macrovascular complications according to sensor-measured TITR/TIR was analysed cross-sectionally in 808 adults with type 1 diabetes. Binary logistic regression was used to evaluate the association between TITR/TIR and the presence of complications without adjustment, with adjustment for HbA1c, and with adjustment for HbA1c and other confounding factors (sex, age, diabetes duration, BMI, BP, lipid profile, smoking, and use of statins and renin-angiotensin-aldosterone system inhibitors). RESULTS: The mean TITR and TIR were 33.9 ± 12.8% and 52.5 ± 15.0%, respectively. Overall, 46.0% had any microvascular complication (34.5% diabetic retinopathy, 23.8% diabetic nephropathy, 16.0% DPN) and 16.3% suffered from any macrovascular complication. The prevalence of any microvascular complication, diabetic retinopathy, diabetic nephropathy and a cerebrovascular accident (CVA) decreased with increasing TITR/TIR quartiles (all ptrend<0.05). Each 10% increase in TITR was associated with a lower incidence of any microvascular complication (OR 0.762; 95% CI 0.679, 0.855; p<0.001), diabetic retinopathy (OR 0.757; 95% CI 0.670, 0.856; p<0.001), background diabetic retinopathy (OR 0.760; 95% CI 0.655, 0.882; p<0.001), severe diabetic retinopathy (OR 0.854; 95% CI 0.731, 0.998; p=0.048), diabetic nephropathy (OR 0.799; 95% CI 0.699, 0.915; p<0.001), DPN (OR 0.837; 95% CI 0.717, 0.977; p=0.026) and CVA (OR 0.651; 95% CI 0.470, 0.902; p=0.010). The independent association of TITR with any microvascular complication (OR 0.867; 95% CI 0.762, 0.988; p=0.032), diabetic retinopathy (OR 0.837; 95% CI 0.731, 0.959; p=0.010), background diabetic retinopathy (OR 0.831; 95% CI 0.705, 0.979; p=0.027) and CVA (OR 0.619; 95% CI 0.426, 0.899; p=0.012) persisted after adjustment for HbA1c. Similar results were obtained when controlling for HbA1c and other confounding factors. CONCLUSIONS/INTERPRETATION: TITR and TIR are inversely associated with the presence of microvascular complications and CVA in people with type 1 diabetes. Although this study was not designed to establish a causal relationship, this analysis adds validity to the use of TITR and TIR as key measures in glycaemic management. TRIAL REGISTRATION: ClinicalTrials.gov NCT02601729 and NCT02898714.

Comparative impact of Roux-en-Y gastric bypass, sleeve gastrectomy or diet alone on beta-cell function in insulin-treated type 2 diabetes patients.

Although bariatric surgery is an effective treatment for type 2 diabetes by inducing weight loss and augmenting gut hormone secretion, the immediate effect on beta-cell function itself remains to be elucidated in type 2 diabetes. Therefore, a prospective, randomized trial was performed in 30 patients with insulin-treated type 2 diabetes and a body mass index ≥ 35 kg/m2. Patients were randomly assigned (1:1:1) to Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) in combination with protein-sparing modified fast (PSMF), or to PSMF alone. Eu- and hyperglycemic clamps were performed before and 3 weeks after surgery and/or PSMF initiation. The primary outcome was the evolution of insulin sensitivity and beta-cell function after surgery, calculated using the composite measures of glucose disposal rate, insulin secretion rate, and disposition index (DI). Results revealed that markers of insulin sensitivity increased similarly in all arms (p = 0.43). A higher marker for maximal beta-cell function was observed when comparing SG to PSMF (p = 0.007). The DI showed a clear positive evolution after RYGB and SG, but not after PSMF alone. Altogether, these findings indicate that bariatric surgery results in an immediate beta-cell function recovery in insulin-treated type 2 diabetes.

CVOT Summit Report 2023: new cardiovascular, kidney, and metabolic outcomes.

The 9th Cardiovascular Outcome Trial (CVOT) Summit: Congress on Cardiovascular, Kidney, and Metabolic Outcomes was held virtually on November 30-December 1, 2023. This reference congress served as a platform for in-depth discussions and exchange on recently completed outcomes trials including dapagliflozin (DAPA-MI), semaglutide (SELECT and STEP-HFpEF) and bempedoic acid (CLEAR Outcomes), and the advances they represent in reducing the risk of major adverse cardiovascular events (MACE), improving metabolic outcomes, and treating obesity-related heart failure with preserved ejection fraction (HFpEF). A broad audience of endocrinologists, diabetologists, cardiologists, nephrologists and primary care physicians participated in online discussions on guideline updates for the management of cardiovascular disease (CVD) in diabetes, heart failure (HF) and chronic kidney disease (CKD); advances in the management of type 1 diabetes (T1D) and its comorbidities; advances in the management of CKD with SGLT2 inhibitors and non-steroidal mineralocorticoid receptor antagonists (nsMRAs); and advances in the treatment of obesity with GLP-1 and dual GIP/GLP-1 receptor agonists. The association of diabetes and obesity with nonalcoholic steatohepatitis (NASH; metabolic dysfunction-associated steatohepatitis, MASH) and cancer and possible treatments for these complications were also explored. It is generally assumed that treatment of chronic diseases is equally effective for all patients. However, as discussed at the Summit, this assumption may not be true. Therefore, it is important to enroll patients from diverse racial and ethnic groups in clinical trials and to analyze patient-reported outcomes to assess treatment efficacy, and to develop innovative approaches to tailor medications to those who benefit most with minimal side effects. Other keys to a successful management of diabetes and comorbidities, including dementia, entail the use of continuous glucose monitoring (CGM) technology and the implementation of appropriate patient-physician communication strategies. The 10th Cardiovascular Outcome Trial Summit will be held virtually on December 5-6, 2024 ( http://www.cvot.org ).

CD4+ T Cells From Individuals With Type 1 Diabetes Respond to a Novel Class of Deamidated Peptides Formed in Pancreatic Islets.

The ß-cell plays a crucial role in the pathogenesis of type 1 diabetes, in part through the posttranslational modification of self-proteins by biochemical processes such as deamidation. These neoantigens are potential triggers for breaking immune tolerance. We report the detection by LC-MS/MS of 16 novel Gln and 27 novel Asn deamidations in 14 disease-related proteins within inflammatory cytokine-stressed human islets of Langerhans. T-cell clones responsive against one Gln- and three Asn-deamidated peptides could be isolated from peripheral blood of individuals with type 1 diabetes. Ex vivo HLA class II tetramer staining detected higher T-cell frequencies in individuals with the disease compared with control individuals. Furthermore, there was a positive correlation between the frequencies of T cells specific for deamidated peptides, insulin antibody levels at diagnosis, and duration of disease. These results highlight that stressed human islets are prone to enzymatic and biochemical deamidation and suggest that both Gln- and Asn-deamidated peptides can promote the activation and expansion of autoreactive CD4+ T cells. These findings add to the growing evidence that posttranslational modifications undermine tolerance and may open the road for the development of new diagnostic and therapeutic applications for individuals living with type 1 diabetes.

An Insulin-Chromogranin A Hybrid Peptide Activates DR11-Restricted T Cells in Human Type 1 Diabetes.

Hybrid insulin peptides (HIPs) formed through covalent cross-linking of proinsulin fragments to secretory granule peptides are detectable within murine and human islets. The 2.5HIP (C-peptide-chromogranin A [CgA] HIP), recognized by the diabetogenic BDC-2.5 clone, is a major autoantigen in the nonobese diabetic mouse. However, the relevance of this epitope in human disease is currently unclear. A recent study probed T-cell reactivity toward HIPs in patients with type 1 diabetes, documenting responses in one-third of the patients and isolating several HIP-reactive T-cell clones. In this study, we isolated a novel T-cell clone and showed that it responds vigorously to the human equivalent of the 2.5HIP (designated HIP9). Although the responding patient carried the risk-associated DRB1*04:01/DQ8 haplotype, the response was restricted by DRB1*11:03 (DR11). HLA class II tetramer staining revealed higher frequencies of HIP9-reactive T cells in individuals with diabetes than in control participants. Furthermore, in DR11+ participants carrying the DRB4 allele, HIP9-reactive T-cell frequencies were higher than observed frequencies for the immunodominant proinsulin 9-28 epitope. Finally, there was a negative correlation between HIP9-reactive T-cell frequency and age at diagnosis. These results provide direct evidence that this C-peptide-CgA HIP is relevant in human type 1 diabetes and suggest a mechanism by which nonrisk HLA haplotypes may contribute to the development of ß-cell autoimmunity.

Hypoglycaemia after Initiation of CFTR Modulator Therapy in a Cystic Fibrosis Patient without Diabetes.

Introduction: Cystic fibrosis transmembrane regulator (CFTR) modulator therapies improve respiratory function and glycaemic control in patients with cystic fibrosis (CF). The direct effect of CFTR modulator therapies on pancreatic function in patients without preexisting diabetes remains unclear. Case Presentation. An 18-year-old female with CF caused by F508del/F508del mutation, who had no diabetes, developed postprandial hypoglycaemias 6 months after initiation of elexacaftor, tezacaftor, and ivacaftor combination therapy (ETI). Symptoms were persisted after brief discontinuation of ETI, but her symptoms and time-in-hypoglycaemia had improved remarkably by avoiding high glycaemic index-foods. Discussion. This case of hypoglycaemia associated with CFTR modulator therapy in a patient without preexisting diabetes suggests that CFTR modulator therapy has the potential to directly affect glucose homeostasis. There might be an improvement in insulin secretion as well as a reduction in systemic insulin resistance. Conclusion: Treatment of CF patients without diabetes with CFTR modulator therapies can cause recurrent hypoglycaemic episodes which resolve with dietary measures.

Dapagliflozin versus saxagliptin as add-on therapy in patients with type 2 diabetes inadequately controlled with metformin

ABSTRACT Objective: This analysis compared the efficacy and safety of the sodium-glucose cotransporter-2 (SGLT2) inhibitor, dapagliflozin, and the dipeptidyl peptidase-4 (DPP4) inhibitor, saxagliptin, both added on to metformin. Materials and methods: This was a post-hoc analysis from a double-blind, randomized, 24-week clinical trial (NCT01606007) of patients with type 2 diabetes (T2D) inadequately controlled with metformin. We compared the dapagliflozin 10 mg (n = 179) and saxagliptin 5 mg (n = 176) treatment arms. Results: Dapagliflozin showed significantly greater mean reductions versus saxagliptin in HbA1c (difference versus saxagliptin [95% CI]: −0.32% [-0.54, −0.10]; p < 0.005), fasting plasma glucose (-0.98 [-1.42, −0.54] mmol/L; p < 0.0001), body weight (-2.39 [-3.08, −1.71] kg; p < 0.0001) and systolic blood pressure (SBP) (-3.89 [-6.15, −1.63] mmHg; p < 0.001). More dapagliflozintreated than saxagliptin-treated patients achieved the composite endpoint of HbA1c reduction ≥ 0.5%, weight loss ≥ 2 kg, SBP reduction ≥ 2 mmHg and no major/minor hypoglycemia (24% versus 7%). No major events of hypoglycemia were reported. More patients on dapagliflozin (6%) versus saxagliptin (0.6%) experienced genital infections. Conclusion: Dapagliflozin demonstrated greater glycemic efficacy than saxagliptin with additional benefits on weight and SBP, and the safety profile was consistent with previous studies.