Cardiovascular effects of glucagon-like peptide 1 receptor agonists: from mechanistic studies in humans to clinical outcomes

A review of serious adverse events linked with GLP-1 agonists in type 2 diabetes mellitus and obesity treatment

Glucagon-like peptide-1 (GLP-1) agonists play a crucial role in treating type 2 diabetes mellitus and obesity by providing glycemic control and aiding weight management. Despite their widespread use, concerns about serious adverse events have prompted extensive research. This review aims to describe the current understanding of serious adverse events associated with GLP-1 agonists. A comprehensive search of PubMed, Google Scholar and Embase databases was performed starting from 2010. Studies reporting evidence of an association between GLP-1 agonists and serious adverse events from 22 articles (5 case reports, 5 randomized controlled trials (RCTs), 9 real-world data cohort analyses, 2 meta-analyses and 1 systematic review and meta-analysis) were included and categorized by the type of adverse event. While some studies reported risks, including anaphylaxis, cardiovascular, gastrointestinal, psychiatric and thyroid-related events, others found no significant associations. The evidence remains mixed, necessitating further research to fully understand the safety profile of GLP-1 agonists and inform clinical practice.

SGLT2 Inhibitors vs GLP-1 Receptor Agonists and Clinical Outcomes in Patients With Diabetes With/Without Atrial Fibrillation

CONTEXT

The coexistence of diabetes mellitus and atrial fibrillation (AF) is associated with substantial risks of adverse cardiovascular events.

OBJECTIVE

The relevant outcomes associated with the use of a sodium-glucose cotransporter-2 inhibitor (SGLT2i) vs glucagon-like peptide-1 receptor agonists (GLP-1RAs) among patients with type 2 diabetes (T2D) with/without concomitant AF remain unknown.

METHODS

In this nationwide retrospective cohort study from the Taiwan National Health Insurance Research Database, there were 344 392 and 31 351 patients with T2D without AF, and 11 462 and 816 T2D patients with AF treated with SGLT2is and GLP-1RAs, respectively, from May 1, 2016, to December 31, 2019. Patients were followed from the drug index date until the occurrence of study events, discontinuation of the index drug, or the end of the study period (December 31, 2020), whichever occurred first. We used propensity score-stabilized weight to balance covariates across the 2 medication groups.

RESULTS

The incidence rate of all study outcomes in patients with concomitant AF was much higher than in those without concomitant AF. For the AF cohort, SGLT2i vs GLP-1RA was associated with a lower risk of hospitalization for heart failure (HF) (2.32 vs 4.74 events per 100 person-years; hazard ratio [HR] 0.48, 95% CI 0.36-0.66), with no benefit seen for the non-AF cohort (P for homogeneity < .01). SGLT2i vs GLP-1RA was associated with a lower risk of composite kidney outcomes both in the AF (0.38 vs 0.79 events per 100 person-years; HR 0.47; 95% CI 0.23-0.96) and the non-AF cohorts (0.09 vs 0.18 events per 100 person-years; HR 0.53; 95% CI 0.43-0.64). There were no significant differences in the risk of major adverse cardiovascular events and all-cause mortality in those who received SGLT2i compared with GLP-1RA for the AF or non-AF cohorts.

CONCLUSION

Considering the high risk of developing HF and/or high prevalence of concomitant HF in patients with concomitant diabetes and AF, whether SGLT2is should be the preferred treatment to GLP-1RAs for such a high-risk population requires further investigation.

Role of endogenous GLP-1 on arterial stiffness and renal haemodynamics following bariatric surgery

BACKGROUND

Cardiovascular trials have revealed the positive impact of GLP-1 receptor agonists (GLP-1 RAs) on cardiovascular outcomes in type 2 diabetes (T2D). However, the specific effects of endogenous GLP-1 on arterial stiffness and renal function remain understudied. This study aimed to explore the influence of endogenous GLP-1 response post-bariatric surgery on arterial stiffness and renal haemodynamic.

METHODS

Thirty individuals with morbid obesity and without T2D, scheduled for Roux-en-Y Gastric Bypass (RYGB), were included. Clinical parameters, 3-hour oral glucose tolerance test (OGTT) with serial sampling for glycaemia, GLP-1 and insulin, carotid-femoral pulse wave velocity (cf-PWV), carotid distensibility coefficient (carotid-DC) and renal resistive index (RRI) measurements were conducted pre-surgery and 1-year post-surgery. Participants were categorized into high-response and low-response groups based on their post-surgery increase in GLP-1 (median increase of 104% and 1%, respectively, pre- vs. post-surgery).

RESULTS

Post-surgery, high-response group demonstrated a greater reduction in cf-PWV (p = .033) and a greater increase (p = .043) in carotid DC compared to low-response group. These enhancements were observed independently of weight loss or blood pressure changes. High-response group exhibited a reduction in RRI (p = .034), although this association was influenced by improvement in pulse pressure. Finally, a multivariate stepwise regression analysis indicated that the percentage increase of GLP1, Δ-GLP1(AUC)%, was the best predictor of percentage decrease in cf-PWV (p = .014).

CONCLUSIONS

Elevated endogenous GLP-1 response following RYGB was associated with improved arterial stiffness and renal resistances, suggesting potential cardio-renal benefits. The findings underscore the potential role of endogenous GLP-1 in influencing vascular and renal haemodynamics independent of traditional weight loss.

High-Salt Diet and Intestinal Microbiota: Influence on Cardiovascular Disease and Inflammatory Bowel Disease

Salt, or sodium chloride, is an essential component of the human diet. Recent studies have demonstrated that dietary patterns characterized by a high intake of salt can influence the abundance and diversity of the gut microbiota, and may play a pivotal role in the etiology and exacerbation of certain diseases, including inflammatory bowel disease and cardiovascular disease. The objective of this review is to synthesize the effects of elevated salt consumption on the gut microbiota, including its influence on gut microbial metabolites and the gut immune system. Additionally, this review will investigate the potential implications of these effects for the development of cardiovascular disease and inflammatory bowel disease. The findings of this study offer novel insights and avenues for the management of two common conditions with significant clinical implications.

Efficacy and safety of polyethylene glycol loxenatide in treating mild-to-moderate diabetic kidney disease in type 2 diabetes patients: a randomized, open-label, clinical trial

Objective

This study aimed to evaluate the efficacy and safety of polyethylene glycol loxenatide (PEG-Loxe) compared to those of dapagliflozin in patients with mild-to-moderate diabetic kidney disease (DKD), a prevalent microvascular complication of type 2 diabetes mellitus (T2DM). The study is set against the backdrop of increasing global diabetes incidence and the need for effective DKD management.

Methods

This study constituted a single-center, randomized, open-label, clinical trial. The trial included patients with mild-to-moderate DKD and suboptimal glycemic control. Eligible participants were randomly allocated to one of the two groups for treatment with either PEG-Loxe or dapagliflozin. The primary endpoint was the change in UACR from baseline at 24 weeks.

Results

Overall, 106 patients were randomized and 80 patients completed the study. Following 24 weeks of treatment, the PEG-Loxe group exhibited a mean percent change in baseline UACR of -29.3% (95% confidence interval [CI]: -34.8, -23.7), compared to that of -31.8% in the dapagliflozin group (95% CI: -34.8, -23.7). Both PEG-Loxe and dapagliflozin showed similar efficacy in reducing UACR, with no significant difference between the groups (p = 0.336). The HbA1c levels decreased by -1.30% (95% CI: -1.43, -1.18) in the PEG-Loxe group and by -1.29% (95% CI: -1.42, -1.17) in the dapagliflozin group (p = 0.905). The TG levels decreased by -0.56 mmol/L (95% CI: -0.71, -0.42) in the PEG-Loxe group and -0.33 mmol/L (95% CI: -0.48, -0.19) in the dapagliflozin group (p = 0.023). Differences in TC, HDL-C, LDL-C, SBP, and DBP levels between the groups were not statistically significant (all p > 0.05). Safety profiles were consistent with previous findings, with gastrointestinal adverse events being more common in the PEG-Loxe group.

Conclusions

PEG-Loxe is as effective as dapagliflozin in improving urine protein levels in patients with mild-to-moderate DKD and offers superior benefits in improving lipid profiles. These findings support the use of PEG-Loxe in DKD management, contributing to evidence-based treatment options.

Clinical Trial Registration

www.chictr.org.cn, identifier ChiCTR2300070919.

Cardiovascular Benefits of GLP-1 Receptor Agonists in Patients Living with Obesity or Overweight: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

GLP-1 receptor agonists (GLP-1 RAs) have emerged as an effective therapeutic class for weight loss. However, the efficacy of these agents in reducing cardiovascular endpoints among patients living with obesity or overweight is unclear.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing GLP-1 RAs versus placebo in patients with obesity or overweight. We searched PubMed, Cochrane, and Embase databases. A random-effects model was used to calculate risk ratios (RRs) and mean differences (MDs), with 95% confidence intervals (CIs).

RESULTS

A total of 13 RCTs were included, with 30,512 patients. Compared with placebo, GLP-1 RAs reduced systolic blood pressure (MD - 4.76 mmHg; 95% CI - 6.03, - 3.50; p < 0.001; I2 = 100%) and diastolic blood pressure (MD - 1.41 mmHg; 95% CI - 2.64, - 0.17; p = 0.03; I2 = 100%). GLP-1 RA significantly reduced the occurrence of myocardial infarction (RR 0.72; 95% CI 0.61, 0.85; p < 0.001; I2 = 0%). There were no significant differences between groups in unstable angina (UA; RR 0.84; 95% CI 0.65, 1.07; p = 0.16; I2 = 0%), stroke (RR 0.91; 95% CI 0.74, 1.12; p = 0.38; I2 = 0%), atrial fibrillation (AF; RR 0.49; 95% CI 0.17, 1.43; p = 0.19; I2 = 22%), and deep vein thrombosis (RR 0.30; 95% CI 0.06, 1.40; p = 0.13; I2 = 0%).

CONCLUSIONS

In patients living with obesity or overweight, GLP-1 RA reduced systolic and diastolic blood pressure and the occurrence of myocardial infarction, with a neutral effect on the occurrence of UA, stroke, AF, and deep vein thrombosis.

REGISTRATION

PROSPERO identifier number CRD42023475226.

The dual GCGR/GLP-1R agonist survodutide: Biomarkers and pharmacological profiling for clinical candidate selection

AIM

To describe the biomarker strategy that was applied to select survodutide (BI 456906), BI 456908 and BI 456897 from 19 dual glucagon receptor (GCGR)/ glucagon-like peptide-1 receptor (GLP-1R) agonists for in-depth pharmacological profiling, which led to the qualification of survodutide as the clinical development candidate.

MATERIALS AND METHODS

Potencies to increase cyclic adenosine monophosphate (cAMP) were determined in Chinese hamster ovary (CHO)-K1 cells stably expressing human GCGR and GLP-1R. Agonism for endogenously expressed receptors was investigated in insulinoma cells (MIN6) for mouse GLP-1R, and in rat primary hepatocytes for the GCGR. In vivo potencies to engage the GLP-1R or GCGR were determined, measuring improvement in oral glucose tolerance (30 nmol/kg) and increase in plasma fibroblast growth factor-21 (FGF21) and liver nicotinamide N-methyltransferase (NNMT) mRNA expression (100 nmol/kg), respectively. Body weight- and glucose-lowering efficacies were investigated in diet-induced obese (DIO) mice and diabetic db/db mice, respectively.

RESULTS

Upon acute dosing in lean mice, target engagement biomarkers for the GCGR and GLP-1R demonstrated a significant correlation (Spearman correlation coefficient with p < 0.05) to the in vitro GCGR and GLP-1R potencies for the 19 dual agonists investigated. Survodutide, BI 456908 and BI 456897 were selected for in-depth pharmacological profiling based on the significant improvement in acute oral glucose tolerance achieved (area under the curve [AUC] of 54%, 57% and 60% vs. vehicle) that was comparable to semaglutide (AUC of 45% vs. vehicle), while showing different degrees of in vivo GCGR engagement, as determined by hepatic NNMT mRNA expression (increased by 15- to 17-fold vs. vehicle) and plasma FGF21 concentrations (increased by up to sevenfold vs. vehicle). In DIO mice, survodutide (30 nmol/kg/once daily), BI 456908 (30 nmol/kg/once daily) and BI 456897 (10 nmol/kg/once daily) achieved a body weight-lowering efficacy from baseline of 25%, 27% and 26%, respectively. In db/db mice, survodutide and BI 456908 (10 and 20 nmol/kg/once daily) significantly lowered glycated haemoglobin (0.4%-0.6%); no significant effect was observed for BI 456897 (3 and 7 nmol/kg/once daily).

CONCLUSIONS

Survodutide was selected as the clinical candidate based on its balanced dual GCGR/GLP-1R pharmacology, engaging the GCGR for robust body weight-lowering efficacy exceeding that of selective GLP-1R agonists, while achieving antidiabetic efficacy that was comparable to selective GLP-1R agonism. Survodutide is currently being investigated in Phase 3 clinical trials in people living with obesity.

Cyclic Adenosine Monophosphate in Cardiac and Sympathoadrenal GLP-1 Receptor Signaling: Focus on Anti-Inflammatory Effects

Glucagon-like peptide-1 (GLP-1) is a multifunctional incretin hormone with various physiological effects beyond its well-characterized effect of stimulating glucose-dependent insulin secretion in the pancreas. An emerging role for GLP-1 and its receptor, GLP-1R, in brain neuroprotection and in the suppression of inflammation, has been documented in recent years. GLP-1R is a G protein-coupled receptor (GPCR) that couples to Gs proteins that stimulate the production of the second messenger cyclic 3',5'-adenosine monophosphate (cAMP). cAMP, acting through its two main effectors, protein kinase A (PKA) and exchange protein directly activated by cAMP (Epac), exerts several anti-inflammatory (and some pro-inflammatory) effects in cells, depending on the cell type. The present review discusses the cAMP-dependent molecular signaling pathways elicited by the GLP-1R in cardiomyocytes, cardiac fibroblasts, central neurons, and even in adrenal chromaffin cells, with a particular focus on those that lead to anti-inflammatory effects by the GLP-1R. Fully elucidating the role cAMP plays in GLP-1R's anti-inflammatory properties can lead to new and more precise targets for drug development and/or provide the foundation for novel therapeutic combinations of the GLP-1R agonist medications currently on the market with other classes of drugs for additive anti-inflammatory effect.

Semaglutide in Cardiometabolic Diseases: SELECTing the Target Population

Cardiovascular diseases remain the main cause of death and disability worldwide. Despite the tremendous improvement in pharmacological, minimally invasive and rehabilitative strategies, global deaths due to cardiovascular diseases are still increasing. Additional risk factors have been recently proposed, and thanks to scientific progress, novel drugs for the control of the main risk factors focusing on the cardiometabolic pathways have been identified. Glucagon-like peptide-1 (GLP-1) receptor agonists represent an innovative step in the management of patients affected by type 2 diabetes mellitus. In addition to their significant efficacy on glycemic homeostasis, some members of this class of drugs have indications in the treatment of obesity. Furthermore, accumulated evidence in the literature has finally suggested a protective role in cardiovascular health. The possible role of GLP-1R agonist drugs (GLP-1RAs) on the mechanisms underlying chronic inflammation and the almost ubiquitous distribution of GLP-1 receptors could explain the enormous versatility of these drugs. Semaglutide is a GLP-1RA recently proven to be effective in cardiovascular outcomes. In the present article, we will review the available data on semaglutide in light of the most recent publications to better characterize the target population achieving cardiovascular benefits.

Thinner is better: Intentional weight loss and cardiovascular risk

The relationship between overweight/obesity and cardiovascular events needs to be tackled. The SELECT trial earns praise in showing that using GLP-1 receptor agonists to reduce overweight/obesity itself, in patients without dysglycemia, has beneficial effects on cardiovascular risk factors and clinical outcomes.1.

GLP-1RA may have varying effects on cardiac structure in patients with ASCVD depending on BMI

Background

Glucagon-like peptide-1 receptor agonist(GLP-1RA) is commonly used in patients with cardiovascular disease due to its significant improvement in the prognosis of atherosclerotic cardiovascular disease (ASCVD). However, previous studies have primarily focused on obese patients, leaving uncertainty regarding whether GLP-1RA can yield similar cardiovascular benefits in individuals with normal or low body weight.

Methods

In this study, we enrolled patients with ASCVD to establish a retrospective cohort. Patients receiving GLP-1RA treatment were assigned to the GLP-1RA group, while a control group was formed by matching age and body mass index (BMI) among patients not receiving GLP-1RA treatment. Each group was further divided into subgroups based on baseline BMI levels: normal weight, overweight, and obesity. A six-month follow-up was conducted to assess changes in patient weight, metabolic indicators, and cardiac structure and function.

Results

Among the normal weight subgroup, no significant weight change was observed after six months of GLP-1RA treatment (57.4 ± 4.8 vs. 58.7 ± 9.2, p = 0.063). However, significant weight reduction was observed in the other two subgroups (Overweight group: 70.0 ± 9.1 vs. 73.1 ± 8.2, p = 0.003, Obesity group: 90.5 ± 14.3 vs. 95.5 ± 16.6, p<0.001). Regardless of baseline BMI levels, GLP-1RA demonstrated significant glucose-lowering effects in terms of metabolic indicators. However, GLP-1RA have a more significant effect on improving blood lipids in overweight and obese patients. The effects of GLP-1RA on cardiac structure exhibited variations among patients with different baseline BMI levels. Specifically, it was observed that the improvement in atrial structure was more prominent in patients with normal body weight(LAD: 33.0 (30.3, 35.5) vs. 35.0 (32.5, 37.1), p = 0.018, LAA (18.0 (16.0, 21.5) vs. 18.5 (16.5, 20.5), p = 0.008), while the enhancement in ventricular structure was more significant in obese subjects(LEVDD: 49.8 ± 5.8 vs. 50.2 ± 5.0, p < 0.001, LVMI: 65.1 (56.2, 71.4) vs. 65.8 (58.9, 80.4), p < 0.039).

Conclusion

According to the study, it was found that the administration of GLP-1RA can have different effects on cardiac structure in patients with different baseline BMI, In obese patients, improvements in ventricular remodeling may be more associated with weight loss mechanisms, while in patients with normal or low BMI, GLP-1RA may directly improve atrial remodeling through GLP-1 receptors in atrial tissue.

Association Between the Magnitude of Glycemic Control and Body Weight Loss With GLP-1 Receptor Agonists and Risk of Atherosclerotic Cardiovascular Disease: A Systematic Review and Meta-analyses of Randomized Diabetes Cardiovascular Outcomes Trials

PURPOSE

Reduction of major atherosclerotic cardiovascular events (MACE) has not been consistent among different glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with type 2 diabetes mellitus (T2DM). The aim of this study was to assess the association between the magnitude of glycemic control, body weight loss, and reductions in systolic blood pressure (SBP) and low-density lipoprotein cholesterol (LDL-C) achieved through GLP-1 RA therapy and MACE.

METHODS

Electronic databases (MEDLINE, CENTRAL, SCOPUS) were searched through March 2023. Studies were eligible if they were cardiovascular outcome trials (CVOTs) comparing GLP-1 RAs versus placebo in T2DM patients. The outcome of interest was 3-point MACE - cardiovascular death, myocardial infarction, or stroke. Random-effects meta-regression analyses evaluated the associations between reductions of HbA1c, body weight, SBP and LDL-C and reduction of MACE.

RESULTS

Overall, 8 CVOTs were included (60079 patients, 30693 with GLP-1 RAs). Reductions of HbA1C were associated with the reduction of 3P-MACE (Log RR -0.290 [95% CI -0.515;-0.064], p = 0.012), with an estimated RR reduction of 25% for each 1% absolute reduction in HbA1C levels. Body weight loss was associated with the reduction of 3P-MACE (Log RR -0.068 [95% CI -0.135;-0.001], p = 0.047), with an estimated RR reduction of 7% for each 1 kg reduction in body weight. Reductions of SBP (Log RR -0.058 [95% CI -0.192;0.076], p = 0.396) and LDL-C (Log RR -0.602 [95% CI -4.157;2.953], p = 0.740) were not associated with the reduction of 3P-MACE.

CONCLUSIONS

In T2DM patients, more potent GLP-1 RAs in reducing HbA1c and body weight were associated with greater reductions of MACE.

Endogenous glucagon-like peptide (GLP)-1 as alternative for GLP-1 receptor agonists: Could this work and how?

In recent years, we have witnessed the many beneficial effects of glucagon-like peptide (GLP)-1 receptor agonists, including the reduction in cardiovascular risk in patients with type 2 diabetes, and the reduction of body weight in those with obesity. Increasing evidence suggests that these agents differ considerably from endogenous GLP-1 when it comes to their routes of action, although their clinical effects appear to be the same. Given the limitations of the GLP-1 receptor agonists, could it be useful to develop agents which stimulate GLP-1 release? Here we will discuss the differences and similarities between GLP-1 receptor agonists and endogenous GLP-1, and will detail how endogenous GLP-1-when stimulated appropriately-could have clinically relevant effects.

Effects of Incretin-Based Treatment on the Diastolic (Dys)Function in Patients with Uncontrolled Type 2 Diabetes Mellitus: A Prospective Study with 1-Year Follow-Up

Left ventricular diastolic dysfunction (DD) is a subclinical cardiac abnormality in patients with type 2 diabetes mellitus (T2DM) that can progress to heart failure (HF) and increase cardiovascular risk. This prospective study evaluated the DD in T2DM patients without atherosclerotic cardiovascular disease after one year of incretin-based drugs added to standard treatment. Of the 138 enrolled patients (49.30% male, mean age 57.86 ± 8.82, mean T2DM history 5 years), 71 were started on dipeptidyl peptidase-4 inhibitor sitagliptin/saxagliptin, 21 on glucagon-like peptide-1 receptor agonist exenatide, and 46 formed the control group (metformin and sulphonylurea/acarbose). At baseline, 71 patients had grade 1 DD, another 12 had grade 2 and 3 DD, and 15 had indeterminate DD. After one year, DD was evidenced in 50 cases. Diastolic function improved in 9 cases, and 27 patients went from grade 1 to indeterminate DD. The active group benefited more, especially patients treated with exenatide; their metabolic and inflammation profiles also improved the most. An in-depth analysis of echocardiographic parameters and paraclinical results in the context of literature data justifies the conclusion that early assessment of diastolic function in T2DM patients is necessary and the benefits of affordable incretin-based treatment may extend to subclinical cardiovascular manifestations such as DD.

Spatially resolved multiomics of human cardiac niches

The function of a cell is defined by its intrinsic characteristics and its niche: the tissue microenvironment in which it dwells. Here we combine single-cell and spatial transcriptomics data to discover cellular niches within eight regions of the human heart. We map cells to microanatomical locations and integrate knowledge-based and unsupervised structural annotations. We also profile the cells of the human cardiac conduction system1. The results revealed their distinctive repertoire of ion channels, G-protein-coupled receptors (GPCRs) and regulatory networks, and implicated FOXP2 in the pacemaker phenotype. We show that the sinoatrial node is compartmentalized, with a core of pacemaker cells, fibroblasts and glial cells supporting glutamatergic signalling. Using a custom CellPhoneDB.org module, we identify trans-synaptic pacemaker cell interactions with glia. We introduce a druggable target prediction tool, drug2cell, which leverages single-cell profiles and drug-target interactions to provide mechanistic insights into the chronotropic effects of drugs, including GLP-1 analogues. In the epicardium, we show enrichment of both IgG+ and IgA+ plasma cells forming immune niches that may contribute to infection defence. Overall, we provide new clarity to cardiac electro-anatomy and immunology, and our suite of computational approaches can be applied to other tissues and organs.

Are arrhythmias the drivers of sudden cardiac death in heart failure with preserved ejection fraction? A review

In patients with heart failure with preserved ejection fraction (HFpEF), sudden cardiac death (SCD) accounts for approximately 25-30% of all-cause mortality and 40% of cardiovascular mortality in properly adjudicated large clinical trials. The mechanism of SCD in HFpEF remains unknown but thought to be driven by arrhythmic events. Apart from atrial fibrillation, which is prevalent in approximately 45% of HFpEF patients, the true burden of other cardiac arrhythmias in HFpEF remains undetermined. The incidence and risk of clinically significant advanced cardiac conduction disease with bradyarrhythmias and ventricular arrhythmias remain less known. Recommendations have been made for long-term cardiac rhythm monitoring to determine the incidence of arrhythmias and clarify mechanisms and mode of death in HFpEF patients. In animal studies, spontaneous ventricular arrhythmias and SCD are significantly elevated in HFpEF animals compared with controls without heart failure. In humans, these studies are scant, with a few published small-size studies suggesting an increased incidence of ventricular arrhythmias in HFpEF. Higher rates of clinically significant conduction disease and cardiac pacing are seen in HFpEF compared with the general population. Excepting atrial fibrillation, the predictive effect of other arrhythmias on heart failure hospitalization, all-cause mortality, and precisely SCD remains unknown. Given the high occurrence of SCD in the HFpEF population, it could potentially become a target for therapeutic interventions if driven by arrhythmias. Studies to address these knowledge gaps are urgently warranted. In this review, we have summarized data on arrhythmias and SCD in HFpEF while highlighting avenues for future research in this area.

Meta-Inflammation and New Anti-Diabetic Drugs: A New Chance to Knock Down Residual Cardiovascular Risk

Type 2 diabetes mellitus (DM) represents, with its macro and microvascular complications, one of the most critical healthcare issues for the next decades. Remarkably, in the context of regulatory approval trials, sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide 1 receptor agonists (GLP-1 RAs) proved a reduced incidence of major adverse cardiovascular events (MACEs), i.e., cardiovascular death and heart failure (HF) hospitalizations. The cardioprotective abilities of these new anti-diabetic drugs seem to run beyond mere glycemic control, and a growing body of evidence disclosed a wide range of pleiotropic effects. The connection between diabetes and meta-inflammation seems to be the key to understanding how to knock down residual cardiovascular risk, especially in this high-risk population. The aim of this review is to explore the link between meta-inflammation and diabetes, the role of newer glucose-lowering medications in this field, and the possible connection with their unexpected cardiovascular benefits.

Systolic blood pressure reduction with tirzepatide in patients with type 2 diabetes: insights from SURPASS clinical program

BACKGROUND

Tirzepatide, a once-weekly glucose-dependent insulinotropic polypeptide/ glucagon-like peptide-1 receptor agonist, is approved in the United States, Europe and Japan for the treatment of type 2 diabetes. Across the SURPASS-1 to -5 clinical studies, tirzepatide 5, 10 and 15 mg demonstrated significant improvements in glycated haemoglobin A1c (HbA1c) (- 1.9 to - 2.6%), body weight (- 6.6 to - 13.9%) and systolic blood pressure (SBP) (- 2.8 to - 12.6 mmHg) at the end of study treatment.

METHODS

Post-hoc mediation analyses were conducted to evaluate weight-loss dependent and weight-loss independent effects of tirzepatide on SBP reductions across the 5 SURPASS studies. The safety population (all randomized patients who took at least 1 dose of study drug) of each study was analyzed. Additional analyses were conducted at individual study level or pooled across 5 SURPASS trials.

RESULTS

The difference in mean SBP change from baseline at 40 weeks (total effect) between the tirzepatide and comparator groups was - 1.3 to - 5.1 mmHg (tirzepatide 5 mg), - 1.7 to - 6.5 mmHg (tirzepatide 10 mg) and - 3.1 to - 11.5 mmHg (tirzepatide 15 mg). These SBP reductions were primarily mediated through weight loss, with different degrees of contributions from weight-loss independent effects across the different trials. In the SURPASS-4 study, which enrolled patients with established cardiovascular disease, weight-loss independent effects explained 33% to 57% of difference in SBP change between tirzepatide and insulin glargine groups. In a pooled analysis of the SURPASS-1 to -5 studies, there was a significant (p < 0.001) but weak correlation (r = 0.18 to 0.22) between change in body weight and SBP. Reductions in SBP with tirzepatide were not dependent on concomitant antihypertensive medications at baseline as similar reductions were observed whether participants were receiving them or not (interaction p = 0.77). The largest SBP reductions were observed in the highest baseline category (> 140 mmHg), while those in the first quartile of baseline SBP category (< 122 mmHg) observed no further decrease in SBP.

CONCLUSIONS

Tirzepatide-induced SBP reduction was primarily mediated through weight loss, with different degrees of contributions from weight-loss independent effects across the different trials. SBP reduction was not dependent on antihypertensive medication use but dependent on baseline SBP value, alleviating theoretical concerns of hypotension.

Urinary Proteome Differences in Patients with Type 2 Diabetes Pre and Post Liraglutide Treatment

Diabetes mellitus is a chronic multisystem disease with a high global prevalence. The glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide is known to lower glucose levels and reduce weight. However, the mechanisms underlying the benefits of liraglutide treatment in patients with type 2 diabetes mellitus (T2DM) remain unclear. Twelve male patients with T2DM (pre and post liraglutide treatment) and HbA1c between 8% and 11% were recruited. In the present study, a two-dimensional difference gel electrophoresis (2D-DIGE) matrix-assisted laser desorption/ionization-time of flight (MALDI TOF) mass spectrometric approach combined with bioinformatics and network pathway analysis was used to explore the urine proteomic profile. The mean age of the patients was 52.4 ± 7.5 years. After treatment with liraglutide, a statistically significant change (p < 0.006) was observed in HbA1c with no significant changes in body weight or markers of dyslipidemia. Two-dimensional difference gel electrophoresis identified significant changes (≥1.5-fold change, ANOVA, p ≤ 0.05) in 32 proteins (4 down- and 28 upregulated) in liraglutide post treatment compared to the pre-treatment state. Albumin, serotransferrin, metallothionein-2 (MT-2), and keratins K1 and K10 were found to be upregulated after liraglutide treatment. The patients showed significant improvement in glycemic control after the 12-week treatment with liraglutide. The renoprotective effect of liraglutide may be linked to the increased urinary abundance of MT-2 and the decreased abundance of zinc alpha 2-glycoprotein (ZAG) and Alpha-1 antitrypsin (α1-AT). More studies are needed to elucidate the molecular mechanisms behind the renoprotective effects of liraglutide.

Protection against stroke with glucagon-like peptide-1 receptor agonists: a comprehensive review of potential mechanisms

Several randomized controlled trials have demonstrated the benefits of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on ischemic stroke in patients with diabetes. In this review, we summarize and discuss the potential mechanisms of stroke protection by GLP-1RAs. GLP-1RAs exert multiple anti-atherosclerotic effects contributing to stroke prevention such as enhanced plaque stability, reduced vascular smooth muscle proliferation, increased nitric oxide, and improved endothelial function. GLP-1RAs also lower the risk of stroke by reducing traditional stroke risk factors including hyperglycemia, hypertension, and dyslipidemia. Independently of these peripheral actions, GLP-1RAs show direct cerebral effects in animal stroke models, such as reduction of infarct volume, apoptosis, oxidative stress, neuroinflammation, excitotoxicity, blood-brain barrier permeability, and increased neurogenesis, neuroplasticity, angiogenesis, and brain perfusion. Despite these encouraging findings, further research is still needed to understand more thoroughly the mechanisms by which GLP-1RAs may mediate stroke protection specifically in the human diabetic brain.

New-Onset Atrial Fibrillation in Patients With Type 2 Diabetes Treated With Novel Glucose-Lowering Therapies

CONTEXT

Whether sodium-glucose cotransporter 2 inhibitors (SGLT2is) are associated with lower risk of new-onset atrial fibrillation (AF) compared with glucagon-like peptide-1 receptor agonists (GLP-1RAs) in patients with type 2 diabetes was unknown.

OBJECTIVE

We aimed to determine the comparative risk of new-onset AF with SGLT2is vs GLP-1RAs in Asian patients with type 2 diabetes in a real-world setting.

METHODS

We used medical data from a multicenter health care provider in Taiwan and enrolled 16 566 and 2746 patients treated with an SGLT2i and a GLP-1RA, respectively, from January 1, 2016, to December 31, 2018. Propensity score weighting was used to balance the baseline covariates. The patients were followed from the drug index date until the occurrence of new-onset AF or the end of the follow-up period.

RESULTS

In this study, 54%, 45%, and 1% of the SGLT2i group patients were treated with empagliflozin, dapagliflozin, and canagliflozin, respectively, and 65% and 35% of the GLP-1RA group patients were treated with liraglutide and dulaglutide, respectively. SGLT2is were associated with lower risk of new-onset AF compared with GLP-1RAs after inverse probability of treatment weighting (subdistribution hazard ratio: 0.72; 95% CI, 0.54-0.97; P = 0.028). Subgroup analysis revealed that this finding was consistent among the following high-risk subgroups: older patients, female patients, and patients with cardiovascular disease or chronic kidney disease.

CONCLUSION

SGLT2is were associated with lower risk of new-onset AF compared with GLP-1RAs among patients with type 2 diabetes mellitus in a real-world practice.

Heart Failure: An Underappreciated Complication of Diabetes. A Consensus Report of the American Diabetes Association

Heart failure (HF) has been recognized as a common complication of diabetes, with a prevalence of up to 22% in individuals with diabetes and increasing incidence rates. Data also suggest that HF may develop in individuals with diabetes even in the absence of hypertension, coronary heart disease, or valvular heart disease and, as such, represents a major cardiovascular complication in this vulnerable population; HF may also be the first presentation of cardiovascular disease in many individuals with diabetes. Given that during the past decade, the prevalence of diabetes (particularly type 2 diabetes) has risen by 30% globally (with prevalence expected to increase further), the burden of HF on the health care system will continue to rise. The scope of this American Diabetes Association consensus report with designated representation from the American College of Cardiology is to provide clear guidance to practitioners on the best approaches for screening and diagnosing HF in individuals with diabetes or prediabetes, with the goal to ensure access to optimal, evidence-based management for all and to mitigate the risks of serious complications, leveraging prior policy statements by the American College of Cardiology and American Heart Association.

New antidiabetic therapy and HFpEF: light at the end of tunnel?

New antidiabetic therapy that includes sodium-glucose co-transporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor (GLP-1R) agonists, and dipeptidyl peptidase 4 (DPP-4) inhibitors showed significant benefit on cardiovascular outcomes in patients with and without type 2 diabetes mellitus, and this was particularly confirmed for SGLT2 inhibitors in subjects with heart failure (HF) with reduced ejection fraction (HFrEF). Their role on patients with HF with preserved ejection fraction (HFpEF) is still not elucidated, but encouraging results coming from the clinical studies indicate their beneficial role. The role of GLP-1R agonists and particularly DPP-4 inhibitors is less clear and debatable. Findings from the meta-analyses are sending positive message about the use of GLP-1R agonists in HFrEF therapy and revealed the improvement of left ventricular (LV) diastolic function in HFpEF. Nevertheless, the relevant medical societies still consider their effect as neutral or insufficiently investigated in HF patients. The impact of DPP-4 inhibitors in HF is the most controversial due to conflicting data that range from negative impact and increased risk of hospitalization due to HF, throughout neutral effect, to beneficial influence on LV diastolic dysfunction. However, this is a very heterogeneous group of medications and some professional societies made clear discrepancy between saxagliptin that might increase risk of HF hospitalization and those DPP-4 inhibitors that have no effect on hospitalization. The aim of this review is to summarize current clinical evidence about the effect of new antidiabetic medications on LV diastolic function and their potential benefits in HFpEF patients.

The risk of incident atrial fibrillation in patients with type 2 diabetes treated with sodium glucose cotransporter-2 inhibitors, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors: a nationwide cohort study

Background

Although a few meta-analyses were conducted to compare the risk of incident atrial fibrillation (AF) between sodium-glucose cotransporter-2 inhibitor (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1RA), and other anti-hyperglycemic agents using indirect or direct comparison, the above analyses showed conflicting results with each other. We aimed to evaluate the risk of new-onset AF associated with the use of SGLT2i, GLP-1RA, and dipeptidyl peptidase-4 inhibitor (DPP4i) among a large longitudinal cohort of diabetic patients.

Methods

In this nationwide retrospective cohort study based on the Taiwan National Health Insurance Research Database, a total of 344,893, 44,370, and 393,100 consecutive patients with type 2 diabetes without preexisting AF receiving GLP-1RA, SGLT2i, and DPP4i, respectively, were enrolled from May 1, 2016, to December 31, 2019. We used 1:1 propensity score matching (PSM) to balance covariates across paired study groups. Patients were followed from the drug index date until the occurrence of AF, death, discontinuation of the index drug, or the end of the study period (December 31, 2020), whichever occurred first.

Results

After PSM, there were 245,442, 43,682, and 39,190 paired cohorts of SGLT2i-DPP4i, SGLT2i-GLP-1RA, and GLP-1RA-DPP4i, respectively. SGLT2i treatment was associated with lower risk of new-onset AF in participants with type 2 diabetes compared with either DPP4i [hazard ratio (HR):0.90; 95% confidential interval (CI) 0.84–0.96; P = 0.0028] or GLP-1RA [HR 0.74; 95% CI 0.63–0.88; P = 0.0007] treatment after PSM. There was no difference in the risk of incident AF between GLP-1RA and DPP4i users [HR 1.01; 95% CI 0.86–1.19; P = 0.8980]. The above findings persisted among several important subgroups. Dapagliflozin was specifically associated with a lower risk of new-onset AF compared with DPP4i (P interaction = 0.02).

Conclusions

Compared with DPP4i, SGLT2i but not GLP-1RA was associated with a lower risk of incident AF in patients with type 2 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01549-x.

Glucagon-Like Peptide 1 Receptor Agonists: A Medication for Obesity Management

PURPOSE OF REVIEW

The burden of obesity worldwide is high and projected to rise. Obesity increases the risk of several cardiovascular diseases and cardiometabolic risk factors; hence, utilizing effective long-term therapies for obesity is of utmost importance. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have emerged as effective therapies that achieve substantial weight loss and improve cardiometabolic risk. The purpose of this review is to discuss the role of GLP-1RAs in obesity management.

RECENT FINDINGS

Two subcutaneous GLP-1RAs, liraglutide and semaglutide, have been evaluated in several clinical trials for weight loss. Liraglutide achieves a mean weight loss of 4-7 kg, and more than 50% of treated individuals achieve 5% or more weight loss. Semaglutide has a greater impact on weight loss, with a mean weight loss of 9-16 kg, and more than 50% of treated individuals achieve 10-15% or more weight loss. These results led to regulatory approval of these agents for weight loss in individuals with obesity, regardless of diabetes status. In addition to weight loss, the benefits of GLP-1RAs extend to other risk factors, such as glycemic control and blood pressure. Gastrointestinal symptoms are the most frequently encountered adverse events with incidences between 5 and 30%. Finally, the cost remains one of the most critical challenges that limit GLP-1RAs use. GLP-1RAs have robust weight loss benefits and are expected to have a critical role in the management of obesity in the coming years. Upcoming studies will evaluate the durability of weight loss achieved with GLP-1RAs and the impact on cardiovascular outcomes.

GLP-1 Receptor Agonists and Coronary Arteries: From Mechanisms to Events

Objective: Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) lower plasma glucose through effects on insulin and glucagon secretion and by decelerating gastric emptying. GLP-1 RAs have many beneficial effects beyond glycemic control, including a protective role on the cardiovascular system. However, underlying mechanisms linking GLP-1 RAs with coronary artery disease are complex and not fully elucidated. In this mini-review, we discuss these mechanisms and subsequent clinical events.

Data Sources: We searched PubMed and Google Scholar for evidence on GLP-1 RAs and coronary events. We did not apply restrictions on article type. We reviewed publications for clinical relevance.

Synopsis of Content: In the first part, we review the current evidence concerning the role of GLP-1 RAs on potential mechanisms underlying the development of coronary events. Specifically, we discuss the role of GLP-1 RAs on atherosclerosis and vasospasms of epicardial coronary arteries, as well as structural/functional changes of coronary microvasculature. In the second part, we summarize the clinical evidence on the impact of GLP-1 RAs in the prevention of acute and chronic coronary syndromes and coronary revascularization. We conclude by discussing existing gaps in the literature and proposing directions for future research.

Association of Metabolic Syndrome With Long-Term Cardiovascular Risks and All-Cause Mortality in Elderly Patients With Obstructive Sleep Apnea

Background

Evidence suggests that an increased risk of major adverse cardiac events (MACE) and all-cause mortality is associated with obstructive sleep apnea (OSA), particularly in the elderly. Metabolic syndrome (MetS) increases cardiovascular risk in the general population; however, less is known about its influence in patients with OSA. We aimed to assess whether MetS affected the risk of MACE and all-cause mortality in elderly patients with OSA.

Methods

From January 2015 to October 2017, 1,157 patients with OSA, aged ≥60 years, no myocardial infarction (MI), and hospitalization for unstable angina or heart failure were enrolled at baseline and were followed up prospectively. OSA is defined as an apnea-hypopnea index of ≥5 events per hour, as recorded by polysomnography. Patients were classified on the basis of the presence of MetS, according to the definition of the National Cholesterol Education Program (NCEP). Incidence rates were expressed as cumulative incidence. Cox proportional hazards analysis was used to estimate the risk of all events. The primary outcomes were MACE, which included cardiovascular death, MI, and hospitalization for unstable angina or heart failure. Secondary outcomes were all-cause mortality, components of MACE, and a composite of all events.

Results

MetS was present in 703 out of 1,157 (60.8%) elderly patients with OSA. During the median follow-up of 42 months, 119 (10.3%) patients experienced MACE. MetS conferred a cumulative incidence of MACE in elderly patients with OSA (log-rank, P < 0.001). In addition, there was a trend for MACE incidence risk to gradually increase in individuals with ≥3 MetS components (P = 0.045). Multivariate analysis showed that MetS was associated with an incidence risk for MACE [adjusted hazard ratio (aHR), 1.86; 95% confidence interval (CI), 1.17–2.96; P = 0.009], a composite of all events (aHR, 1.54; 95% CI, 1.03–2.32; P = 0.036), and hospitalization for unstable angina (aHR, 2.01; 95% CI, 1.04–3.90; P = 0.039). No significant differences in the risk of all-cause mortality and other components of MACE between patients with and without MetS (P > 0.05). Subgroup analysis demonstrated that males (aHR, 2.23; 95% CI, 1.28–3.91, P = 0.05), individuals aged <70 years (aHR, 2.36; 95% CI, 1.27–4.39, P = 0.006), overweight and obese individuals (aHR, 2.32; 95% CI, 1.34–4.01, P = 0.003), and those with moderate-severe OSA (aHR, 1.81;95% CI: 1.05–3.12, P = 0.032) and concomitant MetS were at a higher risk for MACE.

Conclusion

MetS is common in elderly patients with OSA in the absence of MI, hospitalization for unstable angina or heart failure. Further, it confers an independent, increased risk of MACE, a composite of all events, and hospitalization for unstable angina. Overweight and obese males, aged <70 years with moderate-severe OSA combined with MetS presented a significantly higher MACE risk.

Utilization Rates of SGLT2 Inhibitors and GLP-1 Receptor Agonists and Their Facility-Level Variation Among Patients With Atherosclerotic Cardiovascular Disease and Type 2 Diabetes: Insights From the Department of Veterans Affairs

OBJECTIVE

There is mounting evidence regarding the cardiovascular benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide 1 receptor agonists (GLP-1 RA) among patients with atherosclerotic cardiovascular disease (ASCVD) and type 2 diabetes mellitus (T2DM). There is paucity of data assessing real-world practice patterns for these drug classes. We aimed to assess utilization rates of these drug classes and facility-level variation in their use.

RESEARCH DESIGN AND METHODS

We used the nationwide Veterans Affairs (VA) health care system data set from 1 January 2020 to 31 December 2020 and included patients with established ASCVD and T2DM. Among these patients, we assessed the use of SGLT2i and GLP-1 RA and the facility-level variation in their use. Facility-level variation was computed using median rate ratios (MRR), a measure of likelihood that two random facilities differ in use of SGLT2i and GLP-1 RA in patients with ASCVD and T2DM.

RESULTS

Among 537,980 patients with ASCVD and T2DM across 130 VA facilities, 11.2% of patients received an SGLT2i while 8.0% of patients received a GLP-1 RA. Patients receiving these cardioprotective glucose-lowering drug classes were on average younger and had a higher proportion of non-Hispanic Whites. Overall, median (10th-90th percentile) facility-level rates were 14.92% (9.31-22.50) for SGLT2i and 10.88% (4.44-17.07) for GLP-1 RA. There was significant facility-level variation among SGLT2i use-MRRunadjusted: 1.41 (95% CI 1.35-1.47) and MRRadjusted: 1.55 (95% CI 1.46 -1.63). Similar facility-level variation was observed for use of GLP-1 RA-MRRunadjusted: 1.34 (95% CI 1.29-1.38) and MRRadjusted: 1.78 (95% CI 1.65-1.90).

CONCLUSIONS

Overall utilization rates of SGLT2i and GLP-1 RA among eligible patients are low, with significantly higher residual facility-level variation in the use of these drug classes. Our results suggest opportunities to optimize their use to prevent future adverse cardiovascular events among these patients.

Effects on weight loss and glycemic control with SAR441255, a potent unimolecular peptide GLP-1/GIP/GCG receptor triagonist

Unimolecular triple incretins, combining the activity of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon (GCG), have demonstrated reduction in body weight and improved glucose control in rodent models. We developed SAR441255, a synthetic peptide agonist of the GLP-1, GCG, and GIP receptors, structurally based on the exendin-4 sequence. SAR441255 displays high potency with balanced activation of all three target receptors. In animal models, metabolic outcomes were superior to results with a dual GLP-1/GCG receptor agonist. Preclinical in vivo positron emission tomography imaging demonstrated SAR441255 binding to GLP-1 and GCG receptors. In healthy subjects, SAR441255 improved glycemic control during a mixed-meal tolerance test and impacted biomarkers for GCG and GIP receptor activation. Single doses of SAR441255 were well tolerated. The results demonstrate that integrating GIP activity into dual GLP-1 and GCG receptor agonism provides improved effects on weight loss and glycemic control while buffering the diabetogenic risk of chronic GCG receptor agonism.

Effects of Resveratrol on Metabolic Indicators in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Previous studies on the effects of resveratrol on metabolic indicators reported contradictory findings, and these indicators have not been frequently studied in patients with type 2 diabetes. In this study, we aimed to examine the effects of resveratrol on metabolic indicators in a specific group of people with type 2 diabetes using the most recent literature.

METHODS

We used RevMan 5.4 and Stata 14.0 software to identify randomized controlled studies on the impact of resveratrol on metabolic indicators in patients with type 2 diabetes using relevant search terms and keywords such as "resveratrol" and "type 2 diabetes" in the China National Knowledge Infrastructure, PubMed, Cochrane, and Embase. Data were expressed as the weighted mean difference (WMD) and 95% confidence interval (CI).

RESULTS

This meta-analysis included 19 studies involving 1151 patients with type 2 diabetes, including 584 patients treated with resveratrol and 567 patients who received placebo. Compared with the control data, large doses of resveratrol (≥1000 mg) reduced fasting blood glucose levels (WMD: -18.76 mg/dL, 95% CI: -23.43, -14.09; P < 0.00001). Additionally, resveratrol reduced systolic blood pressure (WMD: -7.97 mmHg, 95% CI: -10.63, -5.31; P < 0.00001) and diastolic blood pressure (WMD: -3.55 mmHg, 95% CI: -5.18, -1.93; P < 0.00001) in patients with type 2 diabetes but did not improve waist circumference (WMD: 0.05 cm, 95% CI: -1.77, 1.88; P=0.95), triglyceride levels (WMD: -4.49 mg/dL, 95% CI: -24.23, 15.25; P=0.66), or high-density lipoprotein cholesterol levels (WMD: -1.05 mg/dL, 95% CI: -2.44, 0.33; P=0.14) in patients with type 2 diabetes.

CONCLUSION

This systematic review and meta-analysis updated the most recent literature and provided new evidence, proving that resveratrol treatment can reduce systolic blood pressure and diastolic blood pressure. High-dose resveratrol can reduce fasting blood glucose in patients with type 2 diabetes, although it has no effect on waist circumference, triglyceride, and high-density lipoprotein cholesterol.

Glucagon-Like Peptide-1 Receptor Agonists in Type 2 Diabetes Mellitus and Cardiovascular Disease: The Past, Present, and Future

Type 2 diabetes mellitus (T2DM) is associated with high cardiovascular morbidity and mortality, and cardiovascular diseases are the leading causes of death and disability in people with T2DM. Unfortunately, therapies strictly aimed at glycemic control have poorly contributed to a significant reduction in the risk of cardiovascular events. On the other hand, randomized controlled trials have shown that five glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and one exendin-based GLP-1 RA reduced atherosclerotic cardiovascular events in patients with diabetes at high cardiovascular risk. Furthermore, a meta-analysis including these six agents showed a reduction in major adverse cardiovascular events as well as all-cause mortality compared with placebo, regardless of structural homology. Evidence has also shown that some drugs in this class have beneficial effects on renal outcomes, such as preventing the onset of macroalbuminuria. In addition to lowering blood pressure, these drugs also favorably impacted on body weight in large randomized controlled trials as in real-world studies, a result considered a priority in T2DM management; these and other factors may justify the benefits of GLP-1 RAs upon the cardiovascular system, regardless of glycemic control. Finally, studies showed safety with a low risk of hypoglycemia and no increase in pancreatitis events. Given these benefits, GLP-1 RAs were preferentially endorsed in the guidelines of the European and American societies for patients with these conditions. This narrative review provides a current and comprehensive overview of GLP-1 RAs as cardiovascular and renal protective agents, far beyond their use as glucose-lowering drugs, supporting their effectiveness in treating patients with T2DM at high cardiovascular risk.

An update on the safety of insulin-GLP-1 receptor agonist combinations in type 2 diabetes mellitus

INTRODUCTION

Recent development of novel antidiabetic drugs with proven cardiovascular (CV) and renal benefit and positive effect on body weight enable to take a more complex approach toward the management of type 2 diabetes mellitus (T2DM). Fixed-ratio combinations of insulin-GLP-1 receptor agonist (FRC) utilize complementary mechanisms of action of their individual components and address multiple pathologies linked with T2DM at the same time.

AREAS COVERED

There are currently three FRCs on the market: iGlarLixi (glargine and lixisenatide in 2 different formulations) and IDegLira (degludec and liraglutide). We provide an up-to-date review on the rationale for the use of FRCs and their current position in the management of T2DM. We discuss the available evidence from randomized controlled trials, post hoc analyses, indirect comparative studies and real-world data on their effect on glycemic control, risk of hypoglycemia, body weight, CV safety, and their safety profile.

EXPERT OPINION

FRCs represent an efficacious option for treatment intensification from basal insulin or even the first insulin-based therapy in T2DM. Their excellent glucose-lowering efficacy is complemented with lower risk of hypoglycemia in comparison to basal insulin, neutral effect on body weight and the lower risk of gastrointestinal adverse effects in comparison to GLP-1 receptor agonists.

Anti-diabetic drugs and NASH: from current options to promising perspectives

Introduction: Accumulating evidence supports a bidirectional association between nonalcoholic steatohepatitis (NASH) and type 2 diabetes (T2D). There is a clinical challenge to consider pharmaceutical strategies targeting the metabolic dysfunction common to NASH and T2D pathogenesis.Areas covered: By using PubMed, we performed a literature search to review the potential beneficial effect of anti-diabetic and metabolic investigational drugs on NASH.Expert opinion: Since insulin resistance is central in the pathophysiology of both T2D and NASH, there is an urgent need for new insulin sensitizers. Peroxisome proliferator-activated receptor (PPAR) agonists, especially PPARγ and pan-PPARs agonists, have shown some beneficial effects on both NASH and liver fibrosis, but their routine use should be limited by their safety profile. Incretin-based therapies, including glucagon-like peptide 1 receptor agonists (GLP-1 RAs) and the polyagonists (GLP-1, GIP, glucagon) under development are the most promising anti-diabetic drugs for NASH treatment, mainly due to their action on body weight loss. Preliminary, preclinical and early phase studies suggest that SGLT2 inhibitors and fibroblast growth factor (FGF)19 and FGF21-based therapies are promising targets for NASH and T2D treatment. The common weakness for all of these drugs is their limited effect on liver fibrosis, potentially due to short-term trial design.

Hypothalamic GPCR Signaling Pathways in Cardiometabolic Control

Obesity is commonly associated with sympathetic overdrive, which is one of the major risk factors for the development of cardiovascular diseases, such as hypertension and heart failure. Over the past few decades, there has been a growing understanding of molecular mechanisms underlying obesity development with central origin; however, the relative contribution of these molecular changes to the regulation of cardiovascular function remains vague. A variety of G-protein coupled receptors (GPCRs) and their downstream signaling pathways activated in distinct hypothalamic neurons by different metabolic hormones, neuropeptides and monoamine neurotransmitters are crucial not only for the regulation of appetite and metabolic homeostasis but also for the sympathetic control of cardiovascular function. In this review, we will highlight the main GPCRs and associated hypothalamic nuclei that are important for both metabolic homeostasis and cardiovascular function. The potential downstream molecular mediators of these GPCRs will also be discussed.

Silencing circANKRD36 inhibits streptozotocin-induced insulin resistance and inflammation in diabetic rats by targeting miR-145 via XBP1

BACKGROUND

Diabetes mellitus (DM) is defined as a group of metabolic diseases characterized by hyperglycemia, which results from a deficiency in insulin secretion and/or insulin action. In diabetic patients, type 2 diabetes mellitus (T2DM) is in the majority. We explored the effects of circANKRD36 on streptozotocin (STZ)-induced insulin resistance and inflammation in diabetic rats with the aim of uncovering the underlying mechanism.

METHODS

STZ was used to induce the in vivo T2DM rat model. After circANKRD36 interference, blood glucose, insulin and adiponectin were respectively detected. Hematoxylin and eosin (H&E), enzyme-linked immunosorbent assay (ELISA) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) were conducted to examine inflammation and apoptosis in T2DM rats, and western blot was used for detecting apoptosis-related proteins. The binding relationships among circANKRD36, miR-145 and XBP1 were examined by luciferase reporter assay.

RESULTS

Results showed that circANKRD36 was expressed at a high level in T2DM rats, while silencing circANKRD36 led to decreased blood glucose and insulin, accompanied by increased adiponectin level, and ameliorating insulin resistance. Silencing circANKRD36 alleviated the inflammation and suppressed cell apoptosis in the pancreatic tissues of T2DM rats, which was abated by miR-145 inhibitor. The binding of miR-145 to XBP1 was then confirmed. Additionally, miR-145 inhibitor increased the level of XBP1 in T2DM rats, which was decreased in the presence of circANKRD36 silencing.

CONCLUSION

This study is the first to prove that silencing circANKRD36 inhibits STZ-induced insulin resistance and inflammation in diabetic rats by targeting miR- 145 via XBP1. The results warrant the importance of circRNAs as drug target and thereby pave way for the development of newer therapeutic measures for T2DM.

Lipid effects of glucagon-like peptide 1 receptor analogs

PURPOSE OF REVIEW

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are becoming more prominent as a therapeutic choice in diabetes management and their use is being expanded to other indications, such as obesity. Dyslipidemia and cardiovascular disease are common co-morbidities in these populations and understanding the impact of this class of medications on the lipid profile may be an important consideration.

RECENT FINDINGS

Several GLP-1RAs trials demonstrate them to be safe and potentially beneficial for cardiovascular outcomes; improvements in surrogate markers of atherosclerosis have also been observed. Lipid data collected as secondary outcomes from large clinical trials as well as some smaller dedicated trials show that GLP-1RAs can modestly lower low-density lipoprotein (LDL) and total cholesterol (C), and most show modest fasting triglyceride (TG) lowering. Effects on high-density lipoprotein-C have been less consistent. Some have also demonstrated substantial blunting of the postprandial rise in serum TGs. Favorable effects on lipoprotein metabolism, with reduced levels of small dense LDL particles and decreased atherogenic potential of oxidized LDL, have also been seen. Mechanisms underlying these observations have been investigated.

SUMMARY

This review summarizes the data available on the lipid effects of GLP-1RAs, and explores the current understanding of the mechanisms underlying these observed effects.

GLP-1 receptor agonists (GLP-1RAs): cardiovascular actions and therapeutic potential

Type 2 diabetes mellitus (T2DM) is closely associated with cardiovascular diseases (CVD), including atherosclerosis, hypertension and heart failure. Some anti-diabetic medications are linked with an increased risk of weight gain or hypoglycemia which may reduce the efficacy of the intended anti-hyperglycemic effects of these therapies. The recently developed receptor agonists for glucagon-like peptide-1 (GLP-1RAs), stimulate insulin secretion and reduce glycated hemoglobin levels without having side effects such as weight gain and hypoglycemia. In addition, GLP1-RAs demonstrate numerous cardiovascular protective effects in subjects with or without diabetes. There have been several cardiovascular outcomes trials (CVOTs) involving GLP-1RAs, which have supported the overall cardiovascular benefits of these drugs. GLP1-RAs lower plasma lipid levels and lower blood pressure (BP), both of which contribute to a reduction of atherosclerosis and reduced CVD. GLP-1R is expressed in multiple cardiovascular cell types such as monocyte/macrophages, smooth muscle cells, endothelial cells, and cardiomyocytes. Recent studies have indicated that the protective properties against endothelial dysfunction, anti-inflammatory effects on macrophages and the anti-proliferative action on smooth muscle cells may contribute to atheroprotection through GLP-1R signaling. In the present review, we describe the cardiovascular effects and underlying molecular mechanisms of action of GLP-1RAs in CVOTs, animal models and cultured cells, and address how these findings have transformed our understanding of the pharmacotherapy of T2DM and the prevention of CVD.

The current schemes of insulin therapy: Pro and contra

Insulin regimens have been evolving for a century. The schemes used for type 1 (T1D) and type 2 (T2D) diabetes differ due to differences in pathophysiology but share important features. Insulin is required for both types of diabetes when other means of controlling glucose are insufficient. For T1D this requires multiple daily injections or continuous subcutaneous infusion assisted by CGM, whereas in early T2D basal insulin together with oral agents or GLP-1RA is usually effective. In both cases current schemes typically maintain HbA1c levels between 7 and 8%, a range that limits but does not eliminate the long-term complications of diabetes, but do not restore glycemic control to a fully protective level. Inability to control postprandial hyperglycemia without problematic weight gain and hypoglycemia is a leading obstacle in both T1D and long-duration T2D. A greater share of prandial dosing decisions will have to be provided by smart electronic systems. Further changes in the structure or formulation of insulin are of uncertain potential, but schemes including delivery of amylin, GLP-1, and glucagon show promise. More reliable access to insulins, delivery devices, and capable medical advisors will be needed to optimize replacement of this essential hormone.

Evaluation of glucagon-like peptide-1 receptor expression in nondiabetic and diabetic atherosclerotic mice using PET tracer 68Ga-NODAGA-exendin-4

Cardiovascular effects of glucagon-like peptide-1 receptor (GLP-1R) agonist therapies are potentially mediated by anti-inflammatory effects on atherosclerosis. Our study demonstrates that ⁶⁸Ga-NODAGA-exendin-4, a radioligand specifically targeting GLP-1R, detects GLP-1R expression in inflamed atherosclerotic lesions in nondiabetic and diabetic hypercholesterolemic mice. Immunofluorescence staining suggests that GLP-1R is primarily localized in M2 macrophages in lesions. This study describes a new potential tool that may have translational relevance for studies of pharmacological modification of GLP-1R signaling in atherosclerosis.

Newer anti-diabetic therapies with low hypoglycemic risk-potential advantages for frail older people

The prevalence of diabetes is increasing due to increasing aging of the population. Hypoglycemia is a common diabetes-related complication in old age especially in patients with multiple comorbidities and frailty. Hypoglycemia and frailty appear to have a bidirectional relationship reenforcing each other in a negative downhill spiral that leads to an increased risk of adverse events including disability and mortality. The incidence of hypoglycemia in this age group is usually underestimated due to its atypical clinical presentation and difficult recognition by health care professionals. Guidelines generally recommend a relaxed glycemic control in frail older people with diabetes mainly due to the fear of anti-diabetic medications-induced hypoglycemia. The new anti-diabetic therapies of sodium-glucose co-transporter-2 (SGLT-2) inhibitors and glucagon like peptide-1 receptor agonists (GLP-1RA) have consistently shown a cardio-renal protective effect independent of their glycemic control. Contrary to the traditional hypoglycemic agents that either increase insulin stimulation or insulin sensitization with a potential hypoglycemic risk especially sulfonylureas, the new therapies have a novel anti-diabetic mechanisms of action that have a negligible risk of hypoglycemia. The new therapies appear to be both effective and well tolerated in old age. With appropriate patients' selection, most older people will be eligible for the new therapies if well tolerated and no contraindications. In frail older people, we suggest a pragmatic approach of the use of the new therapies based on the concept of the weight status rather than the frailty status. Frail patients with normal or excess weight are likely to gain most from the new therapies due to its favorable metabolic properties in this group, while the use in the underweight frail patients should be largely avoided especially in those with persistent anorexia and weight loss.

Energy substrate metabolism and mitochondrial oxidative stress in cardiac ischemia/reperfusion injury

The heart is the most metabolically flexible organ with respect to the use of substrates available in different states of energy metabolism. Cardiac mitochondria sense substrate availability and ensure the efficiency of oxidative phosphorylation and heart function. Mitochondria also play a critical role in cardiac ischemia/reperfusion injury, during which they are directly involved in ROS-producing pathophysiological mechanisms. This review explores the mechanisms of ROS production within the energy metabolism pathways and focuses on the impact of different substrates. We describe the main metabolites accumulating during ischemia in the glucose, fatty acid, and Krebs cycle pathways. Hyperglycemia, often present in the acute stress condition of ischemia/reperfusion, increases cytosolic ROS concentrations through the activation of NADPH oxidase 2 and increases mitochondrial ROS through the metabolic overloading and decreased binding of hexokinase II to mitochondria. Fatty acid-linked ROS production is related to the increased fatty acid flux and corresponding accumulation of long-chain acylcarnitines. Succinate that accumulates during anoxia/ischemia is suggested to be the main source of ROS, and the role of itaconate as an inhibitor of succinate dehydrogenase is emerging. We discuss the strategies to modulate and counteract the accumulation of substrates that yield ROS and the therapeutic implications of this concept.

GLP-1 Receptor Agonists: Beyond Their Pancreatic Effects

Glucagon like peptide-1 (GLP-1) is an incretin secretory molecule. GLP-1 receptor agonists (GLP-1RAs) are widely used in the treatment of type 2 diabetes (T2DM) due to their attributes such as body weight loss, protection of islet β cells, promotion of islet β cell proliferation and minimal side effects. Studies have found that GLP-1R is widely distributed on pancreatic and other tissues and has multiple biological effects, such as reducing neuroinflammation, promoting nerve growth, improving heart function, suppressing appetite, delaying gastric emptying, regulating blood lipid metabolism and reducing fat deposition. Moreover, GLP-1RAs have neuroprotective, anti-infectious, cardiovascular protective, and metabolic regulatory effects, exhibiting good application prospects. Growing attention has been paid to the relationship between GLP-1RAs and tumorigenesis, development and prognosis in patient with T2DM. Here, we reviewed the therapeutic effects and possible mechanisms of action of GLP-1RAs in the nervous, cardiovascular, and endocrine systems and their correlation with metabolism, tumours and other diseases.

Liraglutide Reduces Carotid Intima-Media Thickness by Reducing Small Dense Low-Density Lipoproteins in a Real-World Setting of Patients with Type 2 Diabetes: A Novel Anti-Atherogenic Effect

INTRODUCTION

Liraglutide has several non-glycemic effects, including those on plasma lipids and lipoproteins, contributing to its cardiovascular benefit; however, the exact underlying mechanisms remain unclear. We investigated a novel anti-atherogenic effect of liraglutide in a real-world prospective study on patients with type 2 diabetes (T2DM).

METHODS

Sixty-two patients with T2DM (31 men, 31 women; mean age ± standard deviation 61 ± 9 years) naïve to incretin-based therapies were treated with liraglutide (1.2 mg/day) as add-on therapy to metformin (1500-3000 mg/day) for 4 months. Laboratory analyses included the assessment of lipoprotein subclass profile by gel electrophoresis (Lipoprint; Quantimetrix Corp., Redondo Beach, CA, USA). Carotid intima-media thickness (cIMT) was assessed by Doppler ultrasonography. Statistical analyses included the paired t test, Spearman correlation and multiple regression analysis.

RESULTS

The addition of liraglutide to metformin monotherapy resulted in significant reductions in fasting glycemia, hemoglobin A1c, body mass index, waist circumference, total cholesterol, triglycerides and low-density lipoprotein (LDL)-cholesterol, as well as in cIMT. There was an increase in the large LDL-1 subfraction, with a concomitant reduction in atherogenic small dense LDL-3 and LDL-4 subfractions. Correlation analysis revealed a significant association between changes in cIMT and changes in small dense LDL-3 subfraction (r = 0.501; p < 0.0001). Multivariate analysis, including all of the measured anthropometric and laboratory parameters, revealed that only changes in the small dense LDL-3 subfraction were independent predictors of changes in cIMT (p < 0.0001).

CONCLUSION

Our findings are the first to show that the vascular benefit of liraglutide in patients with T2DM is associated with reductions in atherogenic small dense LDL. This effect is independent of glycemic control and body weight reduction and may represent one of the key mechanisms by which liraglutide is able to reduce cardiovascular events.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01715428.

Effects of exenatide on microvascular reactivity in patients with type 2 diabetes and coronary artery disease: A randomized controlled study

OBJECTIVE

We studied the effect of the GLP-1RA exenatide on skin microvascular function in patients with T2DM and CAD.

METHODS

Thirty-five patients with T2DM, CAD, and HbA1C 42-86 mmol/mol were randomized to treatment with exenatide or conventional non-GLP-1-based therapy for 12 weeks. Skin microvascular function was examined in the forearm by LDF and iontophoretic application of acetyl choline and SNP, and by PORH at baseline and after 12 weeks. Blood samples for fasting plasma glucose, HbA1C, and lipid profile were collected.

RESULTS

At 12 weeks, patients on exenatide showed reductions in HbA1C (from 63.5 ± 13 to 60.7 ± 14 mmol/mol, p = .065), body weight (from 92.6 ± 16 to 89 ± 16 kg, p < .001), and systolic blood pressure (from 141 ± 13 to 134 ± 16 mm Hg, p < .05) as compared to the conventionally treated group. There were no significant changes in skin microvascular function between or within the two groups at follow-up.

CONCLUSIONS

Three months' daily treatment with the GLP-1RA exenatide in T2DM patients with CAD showed no significant effects on skin microvascular function or blood glucose control, while this study confirms a reduction in body weight and blood pressure by exenatide, as compared to conventional antidiabetic drug treatment.

New hypoglycaemic therapy in frail older people with diabetes mellitus-phenotypic status likely to be more important than functional status

Frail older people are largely excluded from clinical trials and therefore glycaemic targets and optimum hypoglycaemic therapy in this group has not been fully investigated. Guidelines generally recommend tight glycaemic control in functionally fit individuals and relaxed targets in frail ones mainly due to the fear of hypoglycaemia. The newly introduced sodium glucose cotransporter-2 inhibitors and the glucagon like peptide-1 receptor agonists have shown benefit that is independent of glycaemic control and a minimal risk of hypoglycaemia. However, guidelines still express caution about its use in frail older people due to fear of other side effects such as weight loss, hypotension and falls. Some frail older people will miss out on the benefits of this new therapy if frailty is considered as a one entity with a blanket application of guidelines. We propose that frailty should be viewed as two distinct metabolically different phenotypes, the sarcopenic-obese, in which new therapy will improve their metabolic profile and should be liberally used if no contraindications, and the anorexic-malnourished phenotype in which the new therapy should be cautiously considered. In other words, glycaemic targets should be driven by individual's overall function but the use of new therapy should be driven by frailty phenotype.

Glucagon-Like Peptide-1 (GLP-1) in the Integration of Neural and Endocrine Responses to Stress

Glucagon like-peptide 1 (GLP-1) within the brain is produced by a population of preproglucagon neurons located in the caudal nucleus of the solitary tract. These neurons project to the hypothalamus and another forebrain, hindbrain, and mesolimbic brain areas control the autonomic function, feeding, and the motivation to feed or regulate the stress response and the hypothalamic-pituitary-adrenal axis. GLP-1 receptor (GLP-1R) controls both food intake and feeding behavior (hunger-driven feeding, the hedonic value of food, and food motivation). The activation of GLP-1 receptors involves second messenger pathways and ionic events in the autonomic nervous system, which are very relevant to explain the essential central actions of GLP-1 as neuromodulator coordinating food intake in response to a physiological and stress-related stimulus to maintain homeostasis. Alterations in GLP-1 signaling associated with obesity or chronic stress induce the dysregulation of eating behavior. This review summarized the experimental shreds of evidence from studies using GLP-1R agonists to describe the neural and endocrine integration of stress responses and feeding behavior.