Human Epicardial Adipose Tissue Expresses Glucose-dependent Insulinotropic Polypeptide, Glucagon and Glucagon-Like Peptide 1 Receptors as Potential Targets of Pleiotropic Therapies

Survodutide for the Treatment of Obesity: Rationale and Design of the SYNCHRONIZE Cardiovascular Outcomes Trial

Dual agonism of glucagon and glucagon-like peptide-1 (GLP-1) receptors may be more effective than GLP-1 receptor agonism alone in reducing body weight, but the cardiovascular (CV) effects are unknown. The authors describe the rationale and design of SYNCHRONIZE-CVOT, a phase 3, randomized, double-blind, parallel-group, event-driven, CV safety study of survodutide, a dual glucagon and GLP-1 receptor agonist, administered subcutaneously once weekly compared with placebo in adults with a body mass index ≥27 kg/m2 and established CV disease or chronic kidney disease, and/or at least 2 weight-related complications or risk factors for CV disease. The primary endpoint of SYNCHRONIZE-CVOT is time to first occurrence of the composite adjudicated endpoint of 5-point major adverse CV events. This global CV outcomes trial is currently enrolling, with a target recruitment of 4,935 participants. SYNCHRONIZE-CVOT is the first trial that will determine the CV safety and efficacy of survodutide in people with obesity and increased CV risk. (A Study to Test the Effect of Survodutide [BI 456906] on Cardiovascular Safety in People With Overweight or Obesity [SYNCHRONIZE-CVOT]; NCT06077864).

Venous thrombosis and obesity: from clinical needs to therapeutic challenges

Weight bias and stigma have limited the awareness of the systemic consequences related to obesity. As the narrative evolves, obesity is emerging as a driver and enhancer of many pathological conditions. Among these, the risk of venous thromboembolism (VTE) is a critical concern linked to obesity, ranking as the third most common cardiovascular condition. Obesity is recognized as a multifactorial risk factor for VTE, influenced by genetic, demographic, behavioral, and socio-economic conditions. Despite established links, the exact incidence of obesity related VTE in the general population remains largely unknown. The complexity of distinguishing between provoked and unprovoked VTE, coupled with gaps in obesity definition and assessment still complicates a tailored risk assessment of VTE risk. Obesity reactivity, hypercoagulability, and endothelial dysfunction are driven by the so-called 'adiposopathy'. This state of chronic inflammation and metabolic disturbance amplifies thrombin generation and alters endothelial function, promoting a pro-thrombotic environment. Additionally, the inflammation-induced clot formation-also referred to as 'immunothrombosis' further exacerbates VTE risk in people living with obesity. Furthermore, current evidence highlights significant gaps in the management of obesity related VTE, particularly concerning prophylaxis and treatment efficacy of anticoagulants in people living with obesity. This review underscores the need for tailored therapeutic approaches and well-designed clinical trials to address the unique challenges posed by obesity in VTE prevention and management. Advanced research and innovative strategies are imperative to improve outcomes and reduce the burden of VTE in people living with obesity.

Semaglutide and heart failure: Updated meta-analysis

BACKGROUND

Heart failure (HF) is a major contributor to global health challenges, affecting mortality rates and healthcare expenditure. Glucagon-like peptide-1 receptor agonists (GLP-1RA) offer promise in HF management, though their precise impact is unclear. The main objective of this study was to evaluate the effect of semaglutide on HF-related outcomes.

METHODS

We conducted a meta-analysis of studies assessing the effects of semaglutide therapy on HF-related outcomes. This meta-analysis was performed according to PRISMA guidelines. Randomized clinical trials or observational cohorts studies with a follow-up duration ≥ 6 months were included. The random-effects model was performed.

RESULTS

Six randomised clinical trials (n = 28,762 patients) and two observational studies were identified and considered eligible for this systematic review. A total of 14,608 subjects were assigned to the semaglutide group and 14,716 individuals were assigned to control or placebo groups. Overall, this meta-analysis shows that semaglutide use was associated with an decreased risk of HF (OR: 0.74; 95 % CI: 0.58 to 0.94, I2 45 %), compared to placebo or control groups. The analytical evaluation does not suggest publication bias, and the sensitivity analysis demonstrated that the result was robust.

CONCLUSION

This meta-analysis demonstrates that the use of semaglutide is associated with a reduction in clinical events related to HF. As HF is a heterogeneous clinical condition, further studies will be necessary to analyze this association in different subgroups of patients.

Liraglutide effects on epicardial adipose tissue micro-RNAs and intra-operative glucose control

BACKGROUND AND AIM

Epicardial adipose tissue (EAT) plays a role in coronary artery disease (CAD). EAT has regional distribution throughout the heart and each location may have a different genetic profile and function. Glucagon like peptide-1 receptor analogs (GLP-1RAs) reduce cardiovascular risk. However, the short-term effects of GLP-1RA on microRNA (miRNA) profile of each EAT location is unknown. Objective was to evaluate if EAT miRNAs were different between coronary (CORO-EAT), left atrial EAT (LA-EAT) and subcutaneous fat (SAT), and liraglutide can modulate EAT miRNAs expression.

METHODS AND RESULTS

This was a 12-week randomized, double-blind, placebo-controlled study in 38 patients with type 2 diabetes (T2DM) and coronary artery disease (CAD) who were started on either liraglutide or placebo for a minimum of 4 up to 12 weeks prior to coronary artery by-pass grafting (CABG). Fat samples were collected during CABG. miR16, miR155 and miR181a were significantly higher in CORO-EAT and in LA-EAT than SAT (p < 0.01 and p < 0.05) in overall patients. miR16 and miR181-a were significantly higher in CORO-EAT than SAT (p < 0.01), and miR155 and miR181a were higher in LA-EAT than SAT (p < 0.05) in the liraglutide group. Liraglutide-treated patients had better intra-op glucose control than placebo (146 ± 21 vs 160 ± 21 mg/dl, p < 0.01).

CONCLUSIONS

Our study shows that CORO- and LA-miRNAs profiles were significantly different than SAT miRNAs in overall patients and miRNAs were significantly higher in CORO-EAT and LA-EAT than SAT in the liraglutide group. Pre-op liraglutide was also associated with better intra operative glucose control than placebo independently of weight loss.

Combined Sodium-Glucose-Transporters Inhibitors and Glucagon-Like-Peptide Receptor Agonist Compared With Monotherapy Improves Long-Term Survival: A Real-World Registry

BACKGROUND

The benefits of new glucose-lowering agents on cardiovascular disease have been demonstrated in randomized clinical trials. However, more evidence is required to assess the additive value of a combined therapy based on sodium-glucose transporter inhibitors (SGLT2i) and glucagon-like peptide receptor agonists (GLP1ra) in a real-world population.

METHODS

A nonconcurrent prospective study was conducted using integrated electronic medical records from primary care and hospitals obtained through "big data" technologies in a healthy area in Galicia. The study involved patients who were given SGLT2i, GLP1ra, or both treatments between January 2018 and June 2022 and were categorized as either mono- or combined therapy (SGLT2i, GLP1ra, or both). The cumulative risk for different events: hospitalization or mortality, or both, for 1) coronary artery disease, 2) heart failure, 3) cerebrovascular accident, and all-cause mortality were represented by Kaplan-Meier curves and multivariate Cox regression analysis to obtain the hazard ratio (HR) and (95% confidence interval [CI]). Validation was performed in a subpopulation with propensity score matching.

RESULTS

The patients (15,549) who were included were median (standard deviation) 68 (12) years old, with 41% of them being female and 46% experiencing obesity. The median (interquartile range) of follow-up was 19 (8-33) months. The Kaplan-Meier analysis determined that the cumulative risk for coronary artery disease and cerebrovascular accident events was similar among the 3 different therapy groups. However, the combined therapy vs SGLT2i reduced the risk of heart failure events (HR 0.69; 95% CI, 0.56-0.87) or all-cause mortality (HR 0.68; 95% CI, 0.54-0.86). Multivariate Cox regression analysis, after matching with a propensity score, confirmed the benefits of combined therapy regarding SGLT2i or GLP1ra monotherapy.

CONCLUSION

Compared with SGLT2i or GLP1ra alone, combined therapy SGLT2i + GLP1ra reduces heart failure risk and all-cause mortality in a real-world population.

GPCR-mediated regulation of beige adipocyte formation: Implications for obesity and metabolic health

Obesity and its associated complications pose a significant burden on health. The non-shivering thermogenesis (NST) and metabolic capacity properties of brown adipose tissue (BAT), which are distinct from those of white adipose tissue (WAT), in combating obesity and its related metabolic diseases has been well documented. However, beige adipose tissue, the third and relatively novel type of adipose tissue, which emerges in extensive presence of WAT and shares similar favorable metabolic properties with BAT, has garnered considerable attention in recent years. In this review, we focused on the role of G protein-coupled receptors (GPCRs), the largest receptor family and the most successful class of drug targets in humans, in the induction of beige adipocytes. More importantly, we highlight researchers' clinical treatment attempts to ameliorate obesity and other related metabolic diseases through the formation and activation of beige adipose tissue. In summary, this review provides valuable insights into the formation of beige adipose tissue and the involvement of GPCRs, based on the latest advancements in scientific research.

Glycolipid Metabolic Disorders, Metainflammation, Oxidative Stress, and Cardiovascular Diseases: Unraveling Pathways

Glycolipid metabolic disorders (GLMDs) are various metabolic disorders resulting from dysregulation in glycolipid levels, consequently leading to an increased risk of obesity, diabetes, liver dysfunction, neuromuscular complications, and cardiorenal vascular diseases (CRVDs). In patients with GLMDs, excess caloric intake and a lack of physical activity may contribute to oxidative stress (OxS) and systemic inflammation. This study aimed to review the connection between GLMD, OxS, metainflammation, and the onset of CRVD. GLMD is due to various metabolic disorders causing dysfunction in the synthesis, breakdown, and absorption of glucose and lipids in the body, resulting in excessive ectopic accumulation of these molecules. This is mainly due to neuroendocrine dysregulation, insulin resistance, OxS, and metainflammation. In GLMD, many inflammatory markers and defense cells play a vital role in related tissues and organs, such as blood vessels, pancreatic islets, the liver, muscle, the kidneys, and adipocytes, promoting inflammatory lesions that affect various interconnected organs through their signaling pathways. Advanced glycation end products, ATP-binding cassette transporter 1, Glucagon-like peptide-1, Toll-like receptor-4, and sphingosine-1-phosphate (S1P) play a crucial role in GLMD since they are related to glucolipid metabolism. The consequences of this is system organ damage and increased morbidity and mortality.

Excessive accumulation of epicardial adipose tissue promotes microvascular obstruction formation after myocardial ischemia/reperfusion through modulating macrophages polarization

BACKGROUND

Owing to its unique location and multifaceted metabolic functions, epicardial adipose tissue (EAT) is gradually emerging as a new metabolic target for coronary artery disease risk stratification. Microvascular obstruction (MVO) has been recognized as an independent risk factor for unfavorable prognosis in acute myocardial infarction patients. However, the concrete role of EAT in the pathogenesis of MVO formation in individuals with ST-segment elevation myocardial infarction (STEMI) remains unclear. The objective of the study is to evaluate the correlation between EAT accumulation and MVO formation measured by cardiac magnetic resonance (CMR) in STEMI patients and clarify the underlying mechanisms involved in this relationship.

METHODS

Firstly, we utilized CMR technique to explore the association of EAT distribution and quantity with MVO formation in patients with STEMI. Then we utilized a mouse model with EAT depletion to explore how EAT affected MVO formation under the circumstances of myocardial ischemia/reperfusion (I/R) injury. We further investigated the immunomodulatory effect of EAT on macrophages through co-culture experiments. Finally, we searched for new therapeutic strategies targeting EAT to prevent MVO formation.

RESULTS

The increase of left atrioventricular EAT mass index was independently associated with MVO formation. We also found that increased circulating levels of DPP4 and high DPP4 activity seemed to be associated with EAT increase. EAT accumulation acted as a pro-inflammatory mediator boosting the transition of macrophages towards inflammatory phenotype in myocardial I/R injury through secreting inflammatory EVs. Furthermore, our study declared the potential therapeutic effects of GLP-1 receptor agonist and GLP-1/GLP-2 receptor dual agonist for MVO prevention were at least partially ascribed to its impact on EAT modulation.

CONCLUSIONS

Our work for the first time demonstrated that excessive accumulation of EAT promoted MVO formation by promoting the polarization state of cardiac macrophages towards an inflammatory phenotype. Furthermore, this study identified a very promising therapeutic strategy, GLP-1/GLP-2 receptor dual agonist, targeting EAT for MVO prevention following myocardial I/R injury.

Human epicardial fat has a beige profile and contains higher type 2 innate lymphoid cells than subcutaneous fat

OBJECTIVE

Epicardial adipose tissue (EAT) is a visceral fat that has been associated with coronary artery disease and atrial fibrillation. Previous work has revealed that EAT exhibits beige features.

METHODS

First, a new pan-genomic microarray analysis was performed on previously collected paired human EAT and thoracic subcutaneous AT (thSAT) from the EPICAR study (n = 31) to decipher a specific immune signature and its link with browning genes. Then, adaptive (T and B cells) and innate lymphoid cell (ILC1, ILC2, and ILC3) immunophenotyping assay panels, including CD127, CD117, and prostaglandin D2 receptor 2, were performed on prospectively collected paired human multiorgan donors (n = 18; INTERFACE study).

RESULTS

In the EPICAR study, a positive correlation between the T helper cell subtype Th2 immune pathway and browning genes was found in EAT versus thSAT (r = 0.82; p < 0.0001). In the INTERFACE study, this correlation was also observed (r = 0.31; p = 0.017), and a preponderance of CD4+T cells, CD8+T cells, and a few B cells was observed in all ATs (p < 0.0001). An increase in ILCs was observed in visceral AT (VAT) (i.e., EAT + VAT; 30 ± 5 ILCs per gram of AT) compared with subcutaneous counterparts (i.e., thSAT + abdominal SAT; 8 ± 2 ILCs per gram of AT; p = 0.001), with ILC1 being the most frequent (ILC1 > ILC3 > ILC2). Numbers of ILCs per gram of AT correlated with several Th2 or browning genes (IL-13, TNF receptor superfamily member 9 [TNFRSF9], and alkaline phosphatase, biomineralization associated [ALPL]). Interestingly, a specific increase in EAT-ILC2 compared with other ATs was observed, including a significant proportion expressing CD69 and/or CD25 activation markers (97.9% ± 1.2%; p < 0.0001). Finally, more natural killer cells were observed in EAT + VAT than in thSAT + abdominal SAT (p = 0.01). Exclusion of patients with coronary artery disease in the EPICAR and INTERFACE studies did not modify the main findings. Gene expression phenotyping confirmed specific upregulation of Th2 pathway and browning genes (IL-33 and uncoupling protein 1 [UCP-1]) in EAT.

CONCLUSIONS

This is the first study, to our knowledge, to provide a comparison between innate and adaptive lymphoid cells in human EAT. Further studies are ongoing to decipher whether these cells could be involved in EAT beiging.

New Mechanisms to Prevent Heart Failure with Preserved Ejection Fraction Using Glucagon-like Peptide-1 Receptor Agonism (GLP-1 RA) in Metabolic Syndrome and in Type 2 Diabetes: A Review

This review examines the impact of obesity on the pathophysiology of heart failure with preserved ejection fraction (HFpEF) and focuses on novel mechanisms for HFpEF prevention using a glucagon-like peptide-1 receptor agonism (GLP-1 RA). Obesity can lead to HFpEF through various mechanisms, including low-grade systemic inflammation, adipocyte dysfunction, accumulation of visceral adipose tissue, and increased pericardial/epicardial adipose tissue (contributing to an increase in myocardial fat content and interstitial fibrosis). Glucagon-like peptide 1 (GLP-1) is an incretin hormone that is released from the enteroendocrine L-cells in the gut. GLP-1 reduces blood glucose levels by stimulating insulin synthesis, suppressing islet α-cell function, and promoting the proliferation and differentiation of β-cells. GLP-1 regulates gastric emptying and appetite, and GLP-1 RA is currently indicated for treating type 2 diabetes (T2D), obesity, and metabolic syndrome (MS). Recent evidence indicates that GLP-1 RA may play a significant role in preventing HFpEF in patients with obesity, MS, or obese T2D. This effect may be due to activating cardioprotective mechanisms (the endogenous counter-regulatory renin angiotensin system and the AMPK/mTOR pathway) and by inhibiting deleterious remodeling mechanisms (the PKA/RhoA/ROCK pathway, aldosterone levels, and microinflammation). However, there is still a need for further research to validate the impact of these mechanisms on humans.

Dapagliflozin treatment is associated with a reduction of epicardial adipose tissue thickness and epicardial glucose uptake in human type 2 diabetes

OBJECTIVE

We recently demonstrated that treatment with sodium-glucose cotransporter-2 inhibitors (SGLT-2i) leads to an increase in myocardial flow reserve in patients with type 2 diabetes (T2D) with stable coronary artery disease (CAD). The mechanism by which this occurs is, however, unclear. One of the risk factors for cardiovascular disease is inflammation of epicardial adipose tissue (EAT). Since the latter is often increased in type 2 diabetes patients, it could play a role in coronary microvascular dysfunction. It is also well known that SGLT-2i modify adipose tissue metabolism. We aimed to investigate the effects of the SGLT-2i dapagliflozin on metabolism and visceral and subcutaneous adipose tissue thickness in T2D patients with stable coronary artery disease and to verify whether these changes could explain observed changes in myocardial flow.

METHODS

We performed a single-center, prospective, randomized, double-blind, controlled clinical trial with 14 T2D patients randomized 1:1 to SGLT-2i dapagliflozin (10 mg daily) or placebo. The thickness of visceral (epicardial, mediastinal, perirenal) and subcutaneous adipose tissue and glucose uptake were assessed at baseline and 4 weeks after treatment initiation by 2-deoxy-2-[18F]fluoro-D-glucose Positron Emission Tomography/Computed Tomography during hyperinsulinemic euglycemic clamp.

RESULTS

The two groups were well-matched for baseline characteristics (age, diabetes duration, HbA1c, BMI, renal and heart function). Dapagliflozin treatment significantly reduced EAT thickness by 19% (p = 0.03). There was a significant 21.6% reduction in EAT glucose uptake during euglycemic hyperinsulinemic clamp in the dapagliflozin group compared with the placebo group (p = 0.014). There were no significant effects on adipose tissue thickness/metabolism in the other depots explored.

CONCLUSIONS

SGLT-2 inhibition selectively reduces EAT thickness and EAT glucose uptake in T2D patients, suggesting a reduction of EAT inflammation. This could explain the observed increase in myocardial flow reserve, providing new insights into SGLT-2i cardiovascular benefits.

Epicardial adipose tissue, metabolic disorders, and cardiovascular diseases: recent advances classified by research methodologies

Epicardial adipose tissue (EAT) is located between the myocardium and visceral pericardium. The unique anatomy and physiology of the EAT determines its great potential in locally influencing adjacent tissues such as the myocardium and coronary arteries. Classified by research methodologies, this study reviews the latest research progress on the role of EAT in cardiovascular diseases (CVDs), particularly in patients with metabolic disorders. Studies based on imaging techniques demonstrated that increased EAT amount in patients with metabolic disorders is associated with higher risk of CVDs and increased mortality. Then, in-depth profiling studies indicate that remodeled EAT may serve as a local mediator of the deleterious effects of cardiometabolic conditions and plays a crucial role in CVDs. Further, in vitro coculture studies provided preliminary evidence that the paracrine effect of remodeled EAT on adjacent cardiomyocytes can promote the occurrence and progression of CVDs. Considering the important role of EAT in CVDs, targeting EAT might be a potential strategy to reduce cardiovascular risks. Several interventions have been proved effective in reducing EAT amount. Our review provides valuable insights of the relationship between EAT, metabolic disorders, and CVDs, as well as an overview of the methodological constructs of EAT-related studies.

Synergistic Combinations of Gut- and Pancreas-Hormone-Based Therapies: Advancements in Treatments for Metabolic Diseases

Metabolic diseases, such as obesity, type 2 diabetes mellitus (T2DM), cardiovascular disease, and liver disease, have become increasingly prevalent around the world. As an alternative to bariatric surgery, glucagon-like peptide 1 (GLP-1) receptor agonists have been at the forefront of weight loss medication to combat these metabolic complications. Recently, there has been an exciting rapid emergence of new weight loss medications that combine GLP-1 receptor (GLP-1R) agonists with other gut- and pancreatic-derived hormones, such as glucose-dependent insulinotropic polypeptide (GIP) and glucagon (GCG) receptor agonists. Dual-agonist (GLP-1/GIP and GLP-1/GCG) and tri-agonist (GLP-1/GIP/GCG) administration generally result in greater weight loss, reduction of blood sugar and lipid levels, restoration of tissue function, and improvement in whole-body substrate metabolism compared to when GLP-1R agonists are used alone. The aim of this review is to summarize the recent literature of both preclinical and clinical studies on how these emerging gut-peptide therapies further improve weight loss and metabolic health outcomes for various metabolic diseases.

Amino acids contribute to adaptive thermogenesis. New insights into the mechanisms of action of recent drugs for metabolic disorders are emerging

Adaptive thermogenesis is the heat production by muscle contractions (shivering thermogenesis) or brown adipose tissue (BAT) and beige fat (non-shivering thermogenesis) in response to external stimuli, including cold exposure. BAT and beige fat communicate with peripheral organs and the brain through a variegate secretory and absorption processes - controlling adipokines, microRNAs, extracellular vesicles, and metabolites - and have received much attention as potential therapeutic targets for managing obesity-related disorders. The sympathetic nervous system and norepinephrine-releasing adipose tissue macrophages (ATM) activate uncoupling protein 1 (UCP1), expressed explicitly in brown and beige adipocytes, dissolving the electrochemical gradient and uncoupling tricarboxylic acid cycle and the electron transport chain from ATP production. Mounting evidence has attracted attention to the multiple effects of dietary and endogenously synthesised amino acids in BAT thermogenesis and metabolic phenotype in animals and humans. However, the mechanisms implicated in these processes have yet to be conclusively characterized. In the present review article, we aim to define the principal investigation areas in this context, including intestinal microbiota constitution, adipose autophagy modulation, and secretome and metabolic fluxes control, which lead to increased brown/beige thermogenesis. Finally, also based on our recent epicardial adipose tissue results, we summarise the evidence supporting the notion that the new dual and triple agonists of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon (GCG) receptor - with never before seen weight loss and insulin-sensitizing efficacy - promote thermogenic-like amino acid profiles in BAT with robust heat production and likely trigger sympathetic activation and adaptive thermogenesis by controlling amino acid metabolism and ATM expansion in BAT and beige fat.