Promise of SGLT2 Inhibitors in Heart Failure: Diabetes and Beyond

Hyperglycemia-driven signaling bridges between diabetes and cancer

Growing epidemiological evidence indicates an association between obesity, type 2 diabetes, and certain cancers, suggesting the existence of common underlying mechanisms in these diseases. Frequent hyperglycemias in type 2 diabetes promote pro-inflammatory responses and stimulate intracellular metabolic flux which rewires signaling pathways and influences the onset and advancement of different types of cancers. Here, we review the provocative impact of hyperglycemia on a subset of interconnected signalling pathways that regulate (i) cell growth and survival, (ii) metabolism adjustments, (iii) protein function modulation in response to nutrient availability (iv) and cell fate and proliferation and which are driven respectively by PI3K (Phosphoinositide 3-kinase), AMPK (AMP-activated protein kinase), O-GlcNAc (O-linked N-acetylglucosamine) and Wnt/β-catenin. Specifically, we will elaborate on their involvement in glucose metabolism, inflammation, and cell proliferation, highlighting their interplay in the pathogenesis of diabetes and cancer. Furthermore, the influence of antineoplastic and antidiabetic drugs on the unbridled cellular pathways will be examined. This review aims to inspire the next molecular studies to understand how type 2 diabetes may lead to certain cancers. This will contribute to personalized medicine and direct better prevention strategies.

Exploring the therapeutic potential of tetrahydrobiopterin for heart failure with preserved ejection fraction: A path forward

A large number of patients are affected by classical heart failure (HF) symptomatology with preserved ejection fraction (HFpEF) and multiorgan syndrome. Due to high morbidity and mortality rate, hospitalization and mortality remain serious socioeconomic problems, while the lack of effective pharmacological or device treatment means that HFpEF presents a major unmet medical need. Evidence from clinical and basic studies demonstrates that systemic inflammation, increased oxidative stress, and impaired mitochondrial function are the common pathological mechanisms in HFpEF. Tetrahydrobiopterin (BH4), beyond being an endogenous co-factor for catalyzing the conversion of some essential biomolecules, has the capacity to prevent systemic inflammation, enhance antioxidant resistance, and modulate mitochondrial energy production. Therefore, BH4 has emerged in the last decade as a promising agent to prevent or reverse the progression of disorders such as cardiovascular disease. In this review, we cover the clinical progress and limitations of using downstream targets of nitric oxide (NO) through NO donors, soluble guanylate cyclase activators, phosphodiesterase inhibitors, and sodium-glucose co-transporter 2 inhibitors in treating cardiovascular diseases, including HFpEF. We discuss the use of BH4 in association with HFpEF, providing new evidence for its potential use as a pharmacological option for treating HFpEF.

Impact of end stage renal disease on the clinical outcomes of diabetics admitted for heart failure: Analysis of national inpatient sample

Introduction: Patients with diabetes and heart failure (HF) can have varying outcomes depending on whether they also have End Stage Renal Disease (ESRD). This study aimed to compare the outcomes of patients with diabetes and HF with and without ESRD. Methods: Data from the National Inpatient Sample (NIS) 2016-2018 was analyzed to find hospitalizations for patients with HF as the main diagnosis and diabetes as a secondary diagnosis, with and without ESRD. Multivariable logistic and linear regression analysis was used to adjust for confounding factors. Results: In the total cohort of 12215 patients with a principal diagnosis of heart failure and secondary diagnosis of type 2 diabetes, the in-hospital mortality rate was 2.5%. Patients with ESRD had higher odds of in-hospital mortality (1.37x) compared to those without ESRD. The mean difference in length of stay was higher for patients with ESRD (0.49 days) and in total hospital charges (13360 US$). Patients with ESRD had higher odds of developing acute pulmonary edema, cardiac arrest, and requiring endotracheal intubation. However, they had lower odds of developing cardiogenic shock or requiring an intra-aortic balloon pump insertion. Conclusion: The results suggest that ESRD leads to higher in-patient mortality, length of stay, and total hospital charges for patients with diabetes admitted for HF. The lower incidence of cardiogenic shock and intra-aortic balloon pump insertion in patients with ESRD may be due to timely dialysis.

Effect of Dapagliflozin on Indicators of Myocardial Fibrosis and Levels of Inflammatory Factors in Heart Failure Patients

Objective

To explore the effect of dapagliflozin on the myocardial fibrosis and the levels of inflammatory factors in heart failure patients.

Methods

60 patients with T2DM who were diagnosed as acute left heart failure or acute exacerbation of chronic left heart failure in the Department of Cardiology of our hospital from November 1, 2020, to December 31, 2021, during hospitalization were the study subjects. According to the treatment regimen, they were divided into the experimental group (EG) which received dapagliflozin and conventional drugs and the control group (CG) which received conventional drugs, with 30 cases in each group to compare and analyze the clinical indicators such as myocardial fibrosis and inflammatory factors.

Results

The levels of TNF-α, IL-1β, IL-6, and hs-CRP in the two groups were decreased gradually after treatment, and the levels of TNF-α, IL-1β, IL-6, and hs-CRP in the EG were visibly lower compared with those in the CG at week 4 of treatment (P < 0.05). The cardiac function evaluation of patients showed that the levels of LVEF and LVEDD in both groups were gradually improved after treatment, with a significant difference from the fourth week. In other words, compared with the CG, the LVEF level in the EG was obviously higher (P < 0.05), the LVEDD level was distinctly lower (P < 0.05), and the levels of ST2, BNP, and MCP-1 in the EG were clearly lower at week 4 of treatment (P < 0.05) with a statistical significance in difference.

Conclusion

Dapagliflozin has a definite curative effect in heart failure patients with type 2 diabetes mellitus, which can effectively reduce the inflammatory response of patients and inhibit the myocardial fibrosis, and has a potential value in improving cardiac function and promoting prognosis.

Mitochondrial dysfunction in heart failure and its therapeutic implications

The ATP consumption in heart is very intensive to support muscle contraction and relaxation. Mitochondrion is the power plant of the cell. Mitochondrial dysfunction has long been believed as the primary mechanism responsible for the inability of energy generation and utilization in heart failure. In addition, emerging evidence has demonstrated that mitochondrial dysfunction also contributes to calcium dysregulation, oxidative stress, proteotoxic insults and cardiomyocyte death. These elements interact with each other to form a vicious circle in failing heart. The role of mitochondrial dysfunction in the pathogenesis of heart failure has attracted increasing attention. The complex signaling of mitochondrial quality control provides multiple targets for maintaining mitochondrial function. Design of therapeutic strategies targeting mitochondrial dysfunction holds promise for the prevention and treatment of heart failure.

The use of glucagon-like-peptide-1 receptor agonist in the cardiology practice

The presence of type 2 diabetes confronts the patient with an elevated risk to develop atherosclerotic cardiovascular disease (ASCVD), heart failure (HF), or chronic kidney disease (CKD). Glucose control in itself does not prevent these complications in their entirety. More recently several agents within the class of Sodium-Glucose cotransporter 2 inhibitors (SGLT2-I) and Glucagon-like-peptide-1 receptor agonists (GLP-1RA) have emerged as preferred agents to tackle the residual risk of ASCVD, HF, and CKD in patients with type 2 diabetes. Despite compelling trial data and professional society endorsement, the uptake of these agents in clinical practice is low. Especially GLP-1RA is only used in 8% of eligible candidates with type 2 diabetes and <5% of these prescriptions are attributed to cardiologists. This low uptake amongst cardiologists is related to the unfamiliarity with this class, its initiation, and titration, hesitation regarding simultaneous adjustment of other glucose-lowering agents, the unaccustomedness to prescribing injectable agents, and differential medical priorities. This review aims to offer cardiologists a practical tool for the optimal use of a GLP-1RA in their suitable patients and is focussed on the Belgian field of practice.

Pathophysiology and Treatment of Diabetic Cardiomyopathy and Heart Failure in Patients with Diabetes Mellitus

There is a close relationship between diabetes mellitus and heart failure, and diabetes is an independent risk factor for heart failure. Diabetes and heart failure are linked by not only the complication of ischemic heart disease, but also by metabolic disorders such as glucose toxicity and lipotoxicity based on insulin resistance. Cardiac dysfunction in the absence of coronary artery disease, hypertension, and valvular disease is called diabetic cardiomyopathy. Diabetes-induced hyperglycemia and hyperinsulinemia lead to capillary damage, myocardial fibrosis, and myocardial hypertrophy with mitochondrial dysfunction. Lipotoxicity with extensive fat deposits or lipid droplets is observed on cardiomyocytes. Furthermore, increased oxidative stress and inflammation cause cardiac fibrosis and hypertrophy. Treatment with a sodium glucose cotransporter 2 (SGLT2) inhibitor is currently one of the most effective treatments for heart failure associated with diabetes. However, an effective treatment for lipotoxicity of the myocardium has not yet been established, and the establishment of an effective treatment is needed in the future. This review provides an overview of heart failure in diabetic patients for the clinical practice of clinicians.

Sodium-glucose co-transporter-2 inhibitors do not increase the risk of fractures in real-world clinical practice in Korea: A national observational cohort study

AIMS/INTRODUCTION

This study aimed to determine whether sodium-glucose cotransporter-2 inhibitors (SGLT2i) were related to increased fracture risk in adults with type 2 diabetes compared to dipeptidyl peptidase-4 inhibitors (DPP-4i).

MATERIALS AND METHODS

Between May 1, 2016, and December 31, 2018, we conducted a new-user cohort study using the Korean National Health Insurance Service database. Propensity score matching was performed on 478,826 new users of an SGLT2 inhibitor or DPP-4 inhibitor. After propensity score matching on > 80 covariates, 84,460 individuals were initiated on SGLT2i or DPP-4i, with 42,230 individuals in each treatment group. The time to first fracture event was compared between the SGLT2i and DPP-4i groups using Cox proportional hazard models, and the results are reported as hazard ratios (HRs) with 95% confidence intervals (CIs) for fracture occurrence. Subgroup analyses investigated fractures between treatment groups according to baseline characteristics.

RESULTS

Individuals who were started on SGLT2i were not linked with increased fracture risk in both as-treated (AT) and intention-to-treat (ITT) analyses (AT: HR 0.98, 95% CI 0.92-1.04; ITT: HR 0.94, 95% CI 0.89-1.00). We identified no significant interaction between the individuals' age, sex, fracture history, or thiazolidinedione usage in any subgroup analyses, indicating that none of these variables appeared to be impact modifiers in the connection between SGLT2i and fractures.

CONCLUSIONS

Our study found no increase in the risk of fracture among individuals treated with SGLT2i in a real-world clinical setting for type 2 diabetes.

Trends in Antidiabetic Drug Discovery: FDA Approved Drugs, New Drugs in Clinical Trials and Global Sales

Type 2 diabetes mellitus (T2DM) continues to be a substantial medical problem due to its increasing global prevalence and because chronic hyperglycemic states are closely linked with obesity, liver disease and several cardiovascular diseases. Since the early discovery of insulin, numerous antihyperglycemic drug therapies to treat diabetes have been approved, and also discontinued, by the United States Food and Drug Administration (FDA). To provide an up-to-date account of the current trends of antidiabetic pharmaceuticals, this review offers a comprehensive analysis of the main classes of antihyperglycemic compounds and their mechanisms: insulin types, biguanides, sulfonylureas, meglitinides (glinides), alpha-glucosidase inhibitors (AGIs), thiazolidinediones (TZD), incretin-dependent therapies, sodium-glucose cotransporter type 2 (SGLT2) inhibitors and combinations thereof. The number of therapeutic alternatives to treat T2DM are increasing and now there are nearly 60 drugs approved by the FDA. Beyond this there are nearly 100 additional antidiabetic agents being evaluated in clinical trials. In addition to the standard treatments of insulin therapy and metformin, there are new drug combinations, e.g., containing metformin, SGLT2 inhibitors and dipeptidyl peptidase-4 (DPP4) inhibitors, that have gained substantial use during the last decade. Furthermore, there are several interesting alternatives, such as lobeglitazone, efpeglenatide and tirzepatide, in ongoing clinical trials. Modern drugs, such as glucagon-like peptide-1 (GLP-1) receptor agonists, DPP4 inhibitors and SGLT2 inhibitors have gained popularity on the pharmaceutical market, while less expensive over the counter alternatives are increasing in developing economies. The large heterogeneity of T2DM is also creating a push towards more personalized and accessible treatments. We describe several interesting alternatives in ongoing clinical trials, which may help to achieve this in the near future.

The Effects of the New Therapeutic Treatments for Diabetes Mellitus on the Male Reproductive Axis

One of the complications of chronic hyperglycemia and insulin resistance due to type 2 diabetes mellitus (T2DM) on the hypothalamic-pituitary-gonadal axis in men, is the high prevalence of hypogonadotropic hypogonadism, which has been recently defined as functional hypogonadism, characterized by low testosterone associated with inappropriately normal gonadotropin levels. Although the pathophysiology of this hormonal imbalance may be related to several factors, including glycemic control, concomitant sleep apnea, insulin resistance, the main role is determined by the degree of central or visceral obesity and the consequent inflammatory state. Several drugs have been developed to treat T2DM such as glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase 4 inhibitors, and sodium-glucose co-transporter 2 inhibitors. All appear to be effective in ameliorating blood glucose control, by lowering inflammation and body weight, and most seem to reduce the risk of micro- and macrovascular damage as a consequence of uncontrolled diabetes. A few studies have evaluated the impact of these drugs on gonadal function in T2DM patients with hypogonadism, with promising results. This review summarizes the main current knowledge of the effects of these new antidiabetic drugs on the hypothalamus-pituitary-gonadal axis, showing their potential future application in addition to glucose control in dysmetabolic male patients.

Mini Review: Effect of GLP-1 Receptor Agonists and SGLT-2 Inhibitors on the Growth Hormone/IGF Axis

Accumulating evidence supports the early use of glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium glucose transporter-2 inhibitors (SGLT-2is) for the treatment of type 2 diabetes. Indeed, these compounds exert numerous pleiotropic actions that favorably affect metabolism and diabetes comorbidities, showing an additional effect beyond glucose control. Although a substantial amount of knowledge has been generated regarding the mechanism of action of both drug classes, much remains to be understood. Growth hormone (GH) is an important driver for multiple endocrine responses involving changes in glucose and lipid metabolism, and affects several tissues and organs (e.g., bone, heart). It acts directly on several target tissues, including skeletal muscle and bone, but several effects are mediated indirectly by circulating (liver-derived) or locally produced IGF-1. In consideration of the multiple metabolic and cardiovascular effects seen in subjects treated with GLP-1RAs and SGLT-2is (e.g., reduction of hyperglycemia, weight loss, free/fat mass and bone remodeling, anti-atherosclerosis, natriuresis), it is reasonable to speculate that GH and IGF-1 may play a about a relevant role in this context. This narrative mini-review aims to describe the involvement of the GH/IGF-1/IGF-1R axis in either mediating or responding to the effects of each of the two drug classes.

Optimal Type 2 Diabetes Mellitus Management and Active Ageing

Type two diabetes mellitus (T2DM) represents a chronic condition with increasing prevalence worldwide among the older population. The T2DM condition increases the risk of micro and macrovascular complications as well as the risk of geriatric syndromes such as falls, fractures and cognitive impairment. The management of T2DM in the older population represents a challenge for the clinician, and a Comprehensive Geriatric Assessment should always be prioritized, in order to tailor the glycated hemoglobin target according to functional and cognitive status comorbidities, life expectancy and type of therapy. According to the most recent guidelines, older adults with T2DM should be categorized into three groups: healthy patients with good functional status, patients with complications and reduced functionality and patients at the end of life; for each group the target for glycemic control is different, also according to the type of treatment drug. The therapeutic approach should always begin with lifestyle changes; after that, several lines of therapy are available, with different mechanisms of action and potential effects other than glucose level reduction. Particular interest is growing in sodium-glucose cotransporter-2 inhibitors, due to their effect on the cardiovascular system. In this review, we evaluate the therapeutic options available for the treatment of older diabetic patients, to ensure a correct treatment approach.

Influence of receptor selectivity on benefits from SGLT2 inhibitors in patients with heart failure: a systematic review and head-to-head comparative efficacy network meta-analysis

Background

Receptor selectivity of sodium-glucose cotransporter-2 inhibitors (SGLT2i) varies greatly between agents. The overall improvement of cardiovascular (CV) outcomes in heart failure (HF) patients varies between trials. We, therefore, evaluated the comparative efficacy of individual SGLT2i and the influence of their respective receptor selectivity thereon.

Methods

We identified randomized controlled trials investigating the use of SGLT2i in patients with HF—either as the target cohort or as a subgroup of it. Comparators included placebo or any other active treatment. The primary endpoint was the composite of hospitalization for HF or CV death. Secondary outcomes included all-cause mortality, CV mortality, hospitalization for HF, worsening renal function (RF), and the composite of worsening RF or CV death. Evidence was synthesized using network meta-analysis. In addition, the impact of receptor selectivity on outcomes was analysed using meta-regression.

Results

We identified 18,265 patients included in 22 trials. Compared to placebo, selective and non-selective SGLT2i improved fatal and non-fatal HF events. Head-to-head comparisons suggest superior efficacy with sotagliflozin as compared to dapagliflozin, empagliflozin or ertugliflozin. No significant difference was found between canagliflozin and sotagliflozin. Meta-regression analyses show a decreasing benefit on HF events with increasing receptor selectivity of SGLT2i. In contrast, receptor selectivity did not affect mortality and renal endpoints and no significant difference between individual SGLT2i was noted.

Conclusion

Our data point towards a class-effect of SGLT2i on mortality and renal outcomes. However, non-selective SGLT2i such as sotagliflozin may be superior to highly selective SGLT2i in terms of HF outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01913-z.

The effects of liraglutide and dapagliflozin on cardiac function and structure in a multi-hit mouse model of heart failure with preserved ejection fraction

AIMS

Heart failure with preserved ejection fraction (HFpEF) is a multifactorial disease that constitutes several distinct phenotypes, including a common cardiometabolic phenotype with obesity and type 2 diabetes mellitus. Treatment options for HFpEF are limited, and development of novel therapeutics is hindered by the paucity of suitable preclinical HFpEF models that recapitulate the complexity of human HFpEF. Metabolic drugs, like glucagon-like peptide receptor agonist (GLP-1 RA) and sodium-glucose co-transporter 2 inhibitors (SGLT2i), have emerged as promising drugs to restore metabolic perturbations and may have value in the treatment of the cardiometabolic HFpEF phenotype. We aimed to develop a multifactorial HFpEF mouse model that closely resembles the cardiometabolic HFpEF phenotype, and evaluated the GLP-1 RA liraglutide (Lira) and the SGLT2i dapagliflozin (Dapa).

METHODS AND RESULTS

Aged (18-22 months old) female C57BL/6J mice were fed a standardized chow (CTRL) or high-fat diet (HFD) for 12 weeks. After 8 weeks HFD, angiotensin II (ANGII), was administered for 4 weeks via osmotic mini pumps. HFD + ANGII resulted in a cardiometabolic HFpEF phenotype, including obesity, impaired glucose handling, and metabolic dysregulation with inflammation. The multiple hit resulted in typical clinical HFpEF features, including cardiac hypertrophy and fibrosis with preserved fractional shortening but with impaired myocardial deformation, atrial enlargement, lung congestion, and elevated blood pressures. Treatment with Lira attenuated the cardiometabolic dysregulation and improved cardiac function, with reduced cardiac hypertrophy, less myocardial fibrosis, and attenuation of atrial weight, natriuretic peptide levels, and lung congestion. Dapa treatment improved glucose handling, but had mild effects on the HFpEF phenotype.

CONCLUSIONS

We developed a mouse model that recapitulates the human HFpEF disease, providing a novel opportunity to study disease pathogenesis and the development of enhanced therapeutic approaches. We furthermore show that attenuation of cardiometabolic dysregulation may represent a novel therapeutic target for the treatment of HFpEF.

Role of Glucose-Lowering Medications in Erectile Dysfunction

Erectile dysfunction (ED) is a long-term complication of type 2 diabetes (T2D) widely known to affect the quality of life. Several aspects of altered metabolism in individuals with T2D may help to compromise the penile vasculature structure and functions, thus exacerbating the imbalance between smooth muscle contractility and relaxation. Among these, advanced glycation end-products and reactive oxygen species derived from a hyperglycaemic state are known to accelerate endothelial dysfunction by lowering nitric oxide bioavailability, the essential stimulus of relaxation. Although several studies have explained the pathogenetic mechanisms involved in the generation of erectile failure, few studies to date have described the efficacy of glucose-lowering medications in the restoration of normal sexual activity. Herein, we will present current knowledge about the main starters of the pathophysiology of diabetic ED and explore the role of different anti-diabetes therapies in the potential remission of ED, highlighting specific pathways whose activation or inhibition could be fundamental for sexual care in a diabetes setting.

Multi-Organ Protective Effects of Sodium Glucose Cotransporter 2 Inhibitors

Sodium glucose cotransporter 2 inhibitors (SGLT2i) block the reabsorption of glucose by inhibiting SGLT2, thus improving glucose control by promoting the renal excretion of glucose, without requiring insulin secretion. This pharmacological property of SGLT2i reduces body weight and improves insulin resistance in diabetic patients. Such beneficial metabolic changes caused by SGLT2i are expected to be useful not only for glucose metabolism, but also for the protection for various organs. Recent randomized controlled trials (RCTs) on cardiovascular diseases (EMPA-REG OUTCOME trial and CANVAS program) showed that SGLT2i prevented cardiovascular death and the development of heart failure. RCTs on renal events (EMPA-REG OUTCOME trial, CANVAS program, and CREDENCE trial) showed that SGLT2i suppressed the progression of kidney disease. Furthermore, SGLT2i effectively lowered the liver fat content, and our study demonstrated that SGLT2i reduced the degree of hepatic fibrosis in patients at high-risk of hepatic fibrosis. Such promising properties of SGLT2i for cardiovascular, renal, and hepatic protection provide us the chance to think about the underlying mechanisms for SGLT2i-induced improvement of multiple organs. SGLT2i have various mechanisms for organ protection beyond glucose-lowering effects, such as an increase in fatty acids utilization for hepatic protection, osmotic diuresis for cardiac protection, an improvement of insulin resistance for anti-atherogenesis, and an improvement of tubuloglomerular feedback for renal protection.

Sodium glucose cotransporter 2 inhibitors: mechanisms of action in heart failure

Diabetes is a key independent risk factor in the development of heart failure (HF) and a strong, adverse prognostic factor in HF patients. HF remains the primary cause of hospitalisation for diabetics and, as previous studies have shown, when HF occurs in these patients, intensive glycaemic control does not directly improve the prognosis. Recent clinical studies assessing a new class of antidiabetic drugs, sodium-glucose cotransporter 2 inhibitors (SGLT2is) showed some unexpected beneficial results. Patients treated with SGLT2is had a significant decrease in both cardiovascular (CV) and all-cause mortality and less hospitalisations due to HF compared to those given a placebo. These significant clinical benefits occurred quickly after the drugs were administered and were not solely due to improved glycaemic control. These groundbreaking clinical trials’ results have already changed clinical practice in the management of patients with diabetes at high CV risk. These trials have triggered numerous experimental studies aimed at explaining the mechanisms of action of this unique group of drugs. This article presents the current state of knowledge about the mechanisms of action of SGLT2is developed for the treatment of diabetes and which, thanks to their cardioprotective effects, may, in the future, become a treatment for patients with HF.

Short-Term Changes in Albuminuria and Risk of Cardiovascular and Renal Outcomes in Type 2 Diabetes Mellitus: A Post Hoc Analysis of the EMPA-REG OUTCOME Trial

Background

Early reduction in albuminuria with an SGLT2 (sodium‐glucose cotransporter 2) inhibitor may be a positive indicator of long‐term cardiovascular and renal benefits. We assessed changes in albuminuria during the first 12 weeks of treatment and subsequent long‐term cardiovascular and renal risks associated with the SGLT2 inhibitor, empagliflozin, in the EMPA‐REG OUTCOME (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 diabetes Mellitus Patients) trial.

Methods and Results

We calculated the percentage urinary albumin creatinine ratio (UACR) change from baseline to week 12 in 6820 participants who did not experience a cardiovascular outcome (including 3‐point major cardiovascular events and cardiovascular death or hospitalization for heart failure) or renal outcome (defined as 40% decline in estimated glomerular filtration rate from baseline, estimated glomerular filtration rate <15 mL/min per 1.73 m², need for continuous renal‐replacement therapy, or renal death) during the first 12 weeks. Multivariable Cox regression models were used to estimate the hazard ratio (HR) for each 30% reduction in UACR with outcomes. Empagliflozin reduced UACR by 18% (95% CI, 14–22) at week 12 compared with placebo, and increased the likelihood of a >30% reduction in UACR (odds ratio, 1.42; 95% CI, 1.27–1.58; P<0.001). During 3.0 years of follow‐up, 704 major cardiovascular events, 440 cardiovascular deaths/hospitalizations for heart failure, and 168 renal outcomes were observed. Each 30% decrease in UACR during the first 12 weeks was statistically significantly associated with a lower hazard for major cardiovascular events (HR, 0.96; 95% CI, 0.93–0.99; P=0.012), cardiovascular deaths/hospitalizations for heart failure (HR, 0.94; 95% CI, 0.91–0.98; P=0.003), and renal outcomes (HR, 0.83; 95% CI, 0.78–0.89; P<0.001).

Conclusions

Short‐term reduction in UACR was more common with empagliflozin and was statistically significantly associated with a decreased risk of long‐term cardiovascular and renal outcomes.

Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01131676.

Beyond the myocardium? SGLT2 inhibitors target peripheral components of reduced oxygen flux in the diabetic patient with heart failure with preserved ejection fraction

Recent cardiovascular outcome trials have highlighted the propensity of the antidiabetic agents, SGLT2 inhibitors (SGLT2is or -flozin drugs), to exert positive clinical outcomes in patients with cardiovascular disease at risk for major adverse cardiovascular events (MACEs). Of interest in cardiac diabetology is the physiological status of the patient with T2DM and heart failure with preserved ejection fraction (HFpEF), a well-examined association. Underlying this pathologic tandem are the effects that long-standing hyperglycemia has on the ability of the HFpEF heart to adequately deliver oxygen. It is believed that shortcomings in oxygen diffusion or utilization and the resulting hypoxia thereafter may play a role in underlying the clinical sequelae of patients with T2DM and HFpEF, with implications in the long-term decline of extra-cardiac tissue. Oxygen consumption is one of the most critical factors in indexing heart failure disease burden, warranting a probe into the role of SGLT2i on oxygen utility in HFpEF and T2DM. We investigated the role of oxygen flux in the patient with T2DM and HFpEF extending beyond the heart with focuses on cellular metabolism, perivascular fibrosis with endothelial dysfunction, hematologic changes, and renal effects with neurohormonal considerations in the patient with HFpEF and T2DM. Moreover, we give a commentary on potential therapeutic targets of these components with SGLT2i to gain insight into disease burden amelioration in patients with HFpEF and T2DM.

Contemporary choice of glucose lowering agents in heart failure patients with type 2 diabetes

Background: The choice of glucose lowering agent in heart failure (HF)-patients can have a strong effect on HF-related adverse events, with some classes increasing and other classes reducing the risk. Little data is available about the choice of glucose lowering agents in HF-patients with type-2-diabetes.Methods: We performed a cross-sectional single centre point analysis of all patients with both a diagnoses of HF and type-2-diabetes followed in a tertiary HF-clinic. Medical records were used to determine the choice of current glucose lowering agent. Data at the time of cross-sectional analysis was used to determine potential eligibility to a sodium-glucose-linked-transporter-2-inhibitor (SGLT2-inhibitor) based on the enrolment criteria of the EMPAREG-OUTCOME-trial.Results: A total of 571 HF-patients with diabetes were assessed on June the first 2017. The majority of patients were either managed with one or two glucose lowering agents (43% respectively 34%), with metformin (N = 391;61%), Insulin (N = 278;49%) and sulfonylurea (N = 259;45%) being the most frequently employed treatments. SGLT2-inhibitor use was low (N = 7;1%). According to trial criteria 184 patients (32%) qualified for an SGLT2-inhibitor. With main reasons for ineligibility being a HbA1C < 7% (N = 324) or a glomerular-filtration-rate <30 ml/min (N = 154; of whom 101 patients overlapped with HbA1C < 7%). However 54% of patients with a HbA1C < 7% were treated with ≥2 glucose lowering agents from a class other than SGLT-2-inhibiton.Conclusion: Despite potential eligibility, SGLT2-inhibition remains an underused glucose lowering agent in this contemporary HF-population. Additional research is necessary on optimising its implementation in clinical practice, which might include switching glucose lowering therapies in patients at HbA1C-target.

Empagliflozin Ameliorates Obesity-Related Cardiac Dysfunction by Regulating Sestrin2-Mediated AMPK-mTOR Signaling and Redox Homeostasis in High-Fat Diet-Induced Obese Mice

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have favorable cardiovascular outcomes in patients with diabetes. However, whether SGLT2i can improve obesity-related cardiac dysfunction is unknown. Sestrin2 is a novel stress-inducible protein that regulates AMPK-mammalian target of rapamycin (mTOR) and suppresses oxidative damage. The aim of this study was to determine whether empagliflozin (EMPA) improves obesity-related cardiac dysfunction via regulating Sestrin2-mediated pathways in diet-induced obesity. C57BL/6J mice and Sestrin2 knockout mice were fed a high-fat diet (HFD) for 12 weeks and then treated with or without EMPA (10 mg/kg) for 8 weeks. Treating HFD-fed C57BL/6J mice with EMPA reduced body weight and whole-body fat and improved metabolic disorders. Furthermore, EMPA improved myocardial hypertrophy/fibrosis and cardiac function and reduced cardiac fat accumulation and mitochondrial injury. Additionally, EMPA significantly augmented Sestrin2 levels and increased AMPK and endothelial nitric oxide synthase phosphorylation, but inhibited Akt and mTOR phosphorylation. These beneficial effects were partially attenuated in HFD-fed Sestrin2 knockout mice. Intriguingly, EMPA treatment enhanced the Nrf2/HO-1-mediated oxidative stress response, suggesting antioxidant and anti-inflammatory activity. Thus, EMPA improved obesity-related cardiac dysfunction via regulating Sestrin2-mediated AMPK-mTOR signaling and maintaining redox homeostasis. These findings provide a novel mechanism for the cardiovascular protection of SGLT2i in obesity.

Comparative efficacy of empagliflozin and drugs of baseline therapy in post-infarct heart failure in normoglycemic rats

The study aimed to investigate the effects of the sodium-glucose co-transporter 2 (SGLT2) inhibitor empagliflozin on chronic heart failure (HF) in normoglycemic rats. The effects of empagliflozin were compared with the standard medications for HF, e.g., angiotensin-converting enzyme (ACE) inhibitor fosinopril, beta-blocker bisoprolol, and aldosterone antagonist spironolactone. Myocardial infarction (MI) was induced in male Wistar rats via permanent ligation of the left descending coronary artery. One-month post MI, 50 animals were randomized into 5 groups (n = 10): vehicle-treated, empagliflozin (1.0 mg/kg), fosinopril (10 mg/kg), bisoprolol (10 mg/kg), and spironolactone (20 mg/kg). All medications except empagliflozin were titrated within a month and administered per os daily for 3 months. Echocardiography, 24-hour urine volume test, and treadmill exercise tests were performed at the beginning and at the end of the study. Treatment with empagliflozin slowed the progression of left ventricular dysfunction: LV sizes and ejection fraction were not changed and the minute volume was significantly increased (from 52.0 ± 15.5 to 61.2 ± 21.2 ml/min) as compared with baseline. No deaths occurred in empagliflozin group. The 24-hour urine volume tends to be higher in empagliflozin and spironolactone groups than in vehicle and fosinopril group. Moreover, empagliflozin exhibited maximal physical exercise tolerance in comparison with all investigated groups (289 ± 27 s versus 183 ± 61 s in fosinopril group, 197 ± 95 s in bisoprolol group, and 47 ± 46 s in spironolactone group, p = 0.0035 for multiple comparisons). Sodium-glucose co-transporter 2 inhibitor empagliflozin reduced progression of left ventricular dysfunction and improved tolerance of physical exercise in normoglycemic rats with HF. Empagliflozin treatment was superior with respect to physical tolerance compared with fosinopril, bisoprolol, and spironolactone.

DAPA-HF trial: dapagliflozin evolves from a glucose-lowering agent to a therapy for heart failure

Heart failure (HF) continues to be a major global health problem with a notable impact in terms of morbidity and mortality and so, in consequence, with a large unmet necessity for new therapies. The inhibition of sodium-glucose cotransporter 2 (SGLT2) causes glycosuria and natriuresis, leading to reductions in hyperglycemia (antidiabetic effect), body weight, and blood pressure. In this context, outcome trials have been shown to reduce hospitalizations for HF in patients with type 2 diabetes mellitus treated with SGLT2 inhibitors. The underlying protective cardiovascular (CV) mechanisms of these agents are complex, multifactorial, and not entirely understood as, in addition to a diuretic-like function, SGLT2 inhibitors may mitigate glycemic-related toxicity, promote ketogenesis, increase hematocrit, and exert antihypertrophic, antifibrotic, and antiremodeling properties. The DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) trial enrolled 4744 patients with HF and reduced ejection fraction (EF) who were receiving excellent guideline-directed treatment before the addition of dapagliflozin (a SGLT2 inhibitor) or placebo. The DAPA-HF trial clearly showed that dapagliflozin was superior to placebo at preventing CV deaths and HF events. The relative and absolute risk reductions in death and hospitalizations were consistent across subgroups including patients with and without diabetes; so, in consequence, dapagliflozin represents the first in a new class of drug for HF with reduced EF. The recently published Dapagliflozin Effects on Biomarkers, Symptoms, and Functional Status in Patients With Heart Failure With Reduced Ejection Fraction (DEFINE-HF) trial is also described in this review as well as the thought-to-be mechanisms of action of SGLT2 inhibitors beyond their known glucose-lowering effects. There is a vast, ambitious, and promising ongoing clinical investigation program with dapagliflozin and other SGLT2 inhibitors, which may result in changes to the therapeutic approach to HF in a relatively short time.

The historical evolution of knowledge of the involvement of neurohormonal systems in the pathophysiology and treatment of heart failure

Our knowledge of the pathophysiology of heart failure (HF) underwent profound changes during the 1980s. Once thought to be of exclusively structural origin, HF began to be seen as the consequence of hormonal imbalance. A number of seminal studies were published in that decade focusing on the impact of neurohormonal activation in HF. Presently, eight neurohormonal systems are known to have a key role in HF development: four stimulate vasoconstriction and sodium/water retention (the sympathetic nervous system, the renin-angiotensin-aldosterone system [RAAS], endothelin, and the vasopressin-arginine system), while the other four stimulate vasodilation and natriuresis (the prostaglandin system, nitric oxide, the dopaminergic system, and the natriuretic peptide system [NPS]). These systems are strongly interconnected and are subject to intricate regulation, functioning together in a delicate homeostasis. Disruption of this homeostasis is characteristic of HF. This review explores the historical development of knowledge on the impact of the neurohormonal systems on HF pathophysiology, from the first studies to current understanding. In addition, the therapeutic potential of each of these systems is discussed, and currently used neurohormonal antagonists are characterized. Special emphasis is given to the latest drug approved for use in HF with reduced ejection fraction, sacubitril/valsartan. This drug combines two different molecules, acting on two different systems (RAAS and NPS) simultaneously.

CT-IGFBP-4 as a novel prognostic biomarker in acute heart failure

Aims

Insulin‐like growth factor binding protein‐4 (IGFBP‐4) fragments have been shown to predict the risk of major adverse cardiovascular events, including segment‐elevation myocardial infarction, in patients with acute coronary syndrome. We evaluated the prognostic value of the carboxy‐terminal fragment of IGFBP‐4 (CT‐IGFBP‐4) for all‐cause mortality in emergency room patients with acute heart failure (AHF).

Methods and results

CT‐IGFBP‐4, N‐terminal pro brain natriuretic peptide (NT‐proBNP), and C‐reactive protein (CRP) were measured at admission from the lithium‐heparin plasma of 156 patients with AHF. All‐cause mortality was recorded for 1 year. Receiver operator characteristic (ROC) curves, Kaplan–Meier, and Cox proportional hazard ratio analyses were performed to evaluate the prognostic value of the various clinical variables, CT‐IGFBP‐4, NT‐proBNP, CRP, and their combinations. During 1 year of follow‐up, 52 (33.3%) patients died. CT‐IGFBP‐4 only weakly correlated with NT‐proBNP (Pearson correlation coefficient r = 0.16, P = 0.044) and did not correlate with CRP (r = 0.08, P = 0.35), emphasizing the different nature of these biomarkers. The receiver operator characteristic area under the curve (ROC AUC) of CT‐IGFBP‐4 for the prediction of all‐cause mortality (0.727) was significantly higher than that of NT‐proBNP (0.680, P = 0.045) and CRP (0.669, P = 0.016). The combination of CT‐IGFBP‐4, NT‐proBNP, and CRP predicted mortality significantly better (ROC AUC = 0.788) than any of the biomarkers alone (P < 0.01 for all). The addition of CT‐IGFBP‐4 to a clinical prediction model that included age, gender, systolic blood pressure, creatinine, and sodium levels, as well as the history of previous heart failure, coronary artery disease, and hypertension significantly improved the mortality risk prediction (ROC AUC 0.774 vs. 0.699, P = 0.025). Cox hazard analysis indicated that elevated CT‐IGFBP‐4 was independently associated with 1 year mortality (hazard ratio 3.26, P = 0.0008) after adjustment for age, gender, history of previous heart failure, coronary artery disease, hypertension, chronic kidney failure, history of diabetes, heart rate, haemoglobin, plasma sodium, NT‐proBNP, CRP, cystatin C, and elevated cardiac troponin I or T. Patients with increased levels of either two or three of the biomarkers CT‐IGFBP‐4, NT‐proBNP, and CRP had significantly higher mortality risk (adjusted hazard ratio 10.04, P < 0.0001) than patients with increased levels of one or none of the biomarkers.

Conclusions

CT‐IGFBP‐4 was independently associated with all‐cause mortality in patients with AHF. Compared with single biomarkers, the combination of CT‐IGFBP‐4, NT‐proBNP, and CRP improved the prediction of all‐cause mortality in patients with AHF.

Prospect of Sodium-Glucose Co-transporter 2 Inhibitors Combined With Insulin for the Treatment of Type 2 Diabetes

Sodium-glucose co-transporter 2 (SGLT2) inhibitors are a new family of antidiabetic drugs that reduce blood glucose independent of insulin. In this review, we present the advantages and adverse effects of SGLT2 inhibitors plus insulin therapy as a treatment regimen for patients with type 2 diabetes (T2D). Compared with placebo, SGLT2 inhibitors plus insulin therapy could significantly decrease fasting blood glucose and HbA1c, thereby reducing the daily required dose of insulin. A reduction in body weight and improvements in insulin resistance and β-cell function have also been widely reported with this therapy, and other potential advantages, including the reduction in blood pressure, adverse cardiovascular outcomes, and visceral adipose tissue volume, have been revealed. SGLT2 inhibitors cause a greater reduction than dipeptidyl peptidase-4 (DPP-4) inhibitors in body weight and the risk of cardiovascular disease. Furthermore, compared with glucagon-like peptide-1 (GLP-1) agonists, SGLT2 inhibitors reduce blood pressure, and heart failure. As this therapy is an oral preparation, an improvement in patient compliance is also achieved. Despite these advantages, however, combination therapy with SGLT2 inhibitors and insulin has several risks. Although no difference has been found in the incidence of hypoglycemic events and urinary tract infection between the administration of this combination and that of placebo, the risk of genital tract infections was reported to increase with the combination therapy. Additionally, bone adverse effects, euglycemic diabetic ketoacidosis, and volume depletion-and osmotic diuresis-related adverse effects have been observed. Altogether, we could conclude that SGLT2 inhibitors plus insulin therapy is an efficient treatment option for patients with T2D, especially those requiring high daily insulin doses and those with insulin resistance, obesity, and a high risk of cardiovascular events. However, careful monitoring of the adverse effects of this combination is also warranted.

Role of Leptin in Cardiovascular Diseases

The adipocyte-derived adipokine leptin exerts pleiotropic effects, which are essential for the regulation of energy balance and cell metabolism, for controlling inflammatory and immune responses, and for the maintenance of homeostasis of the cardiovascular system. Leptin resistance in obese or type 2 diabetes mellitus (T2DM) patients is defined as a decrease in tissue response to leptin. In the cardiovascular system, leptin resistance exhibits the adverse effect on the heart's response to stress conditions and promoting cardiac remodeling due to impaired cardiac metabolism, increased fibrosis, vascular dysfunction, and enhanced inflammation. Leptin resistance or leptin signaling deficiency results in the risk increase of cardiac dysfunction and heart failure, which is a leading cause of obesity- and T2DM-related morbidity and mortality. Animal studies using leptin- and leptin receptor- (Lepr) deficient rodents have provided many useful insights into the underlying molecular and pathophysiological mechanisms of obese- and T2DM-associated metabolic and cardiovascular diseases. However, none of the animal models used so far can fully recapitulate the phenotypes of patients with obese or T2DM. Therefore, the role of leptin in the human cardiovascular system, and whether leptin affects cardiac function directly or acts through a leptin-regulated neurohumoral pathway, remain elusive. As the prevalence of obesity and diabetes is continuously increasing, strategies are needed to develop and apply human cell-based models to better understand the precise role of leptin directly in different cardiac cell types and to overcome the existing translational barriers. The purpose of this review is to discuss the mechanisms associated with leptin signaling deficiency or leptin resistance in the development of metabolic and cardiovascular diseases. We analyzed and comprehensively addressed substantial findings in pathophysiological mechanisms in commonly used leptin- or Lepr-deficient rodent models and highlighted the differences between rodents and humans. This may open up new strategies to develop directly and reliably applicable models, which resemble the human pathophysiology in order to advance health care management of obesity- and T2DM-related cardiovascular complications.

Integrated Multiomics Approach to Identify Genetic Underpinnings of Heart Failure and Its Echocardiographic Precursors

Background:

Heart failure (HF) may arise from alterations in metabolic, structural, and signaling pathways, but its genetic architecture is incompletely understood. To elucidate potential genetic contributors to cardiac remodeling and HF, we integrated genome-wide single-nucleotide polymorphisms, gene expression, and DNA methylation using a transomics analytical approach.

Methods:

We used robust rank aggregation (where the position of a certain gene in a rank order list [based on statistical significance level] is tested against a randomly shuffled rank order list) to derive an integrative transomic score for each annotated gene associated with a HF trait.

Results:

We evaluated ≤8372 FHS (Framingham Heart Study) participants (54% women; mean age, 55±17 years). Of these, 62 (0.7%) and 35 (0.4%) had prevalent HF with reduced ejection fraction and HF with preserved left ventricular ejection fraction, respectively. During a mean follow-up of 8.5 years (minimum–maximum, 0.005–18.6 years), 223 (2.7%) and 234 (2.8%) individuals developed incident HF with reduced ejection fraction and HF with reduced ejection fraction, respectively. Top genes included MMP20 and MTSS1 (promotes actin assembly at intercellular junctions) for left ventricular systolic function; ITGA9 (receptor for VCAM1 [vascular cell protein 1]) and C5 for left ventricular remodeling; NUP210 (expressed during myogenic differentiation) and ANK1 (cytoskeletal protein) for diastolic function; TSPAN16 and RAB11FIP3 (involved in regulation of actin cytoskeleton) for prevalent HF with reduced ejection fraction; ANKRD13D and TRIM69 for incident HF with reduced ejection fraction; HPCAL1 and PTTG1IP for prevalent HF with reduced ejection fraction; and ZNF146 (close to the COX7A1 enzyme) and ZFP3 (close to SLC52A1 —the riboflavin transporter) for incident HF with reduced ejection fraction. We tested the HF-related top single-nucleotide polymorphisms in the UK biobank, where rs77059055 in TPM1 (minor allele frequency, 0.023; odds ratio, 0.83; P =0.002) remained statistically significant upon Bonferroni correction.

Conclusions:

Our integrative transomics approach offers insights into potential molecular and genetic contributors to HF and its precursors. Although several of our candidate genes have been implicated in HF in animal models, independent replication is warranted.

Optimizing The Management of Obese HFpEF Phenotype: Can We Mind Both The Heart and The Kidney?

The adverse prognostic implications of significant renal dysfunction during treatment of acute decompensated heart failure (HF) in patients with obese HF and preserved ejection fraction (HFpEF) provide strong rationale for development of therapeutic strategies that enhance decongestion while preserving renal function in this cohort. The combination of preload sensitivity, intrinsic renal dysfunction related to obesity, glomerular hyperfiltration, reversible renal hypoperfusion (poor renal arterial perfusion and renal venous congestion), and decreased systemic vascular resistance in obesity may predispose patients to renal hemodynamic compromise during diuresis. Thus, serum creatinine increase should not be evaluated in isolation but rather considered in the context of the entire clinical picture in patients with obese HFpEF.

Loop diuretic use among patients with heart failure and type 2 diabetes treated with sodium glucose cotransporter-2 inhibitors

AIMS

To compare loop diuretic use in patients with comorbid heart failure (HF) and type 2 diabetes (T2D) newly initiated on sodium glucose cotransporter-2 inhibitors (SGLT2Is) versus other oral anti-glycemic agents (AGAs).

METHODS

This analysis used 2013-2015 MarketScan Medicare Supplemental claims data. HF and T2D patients were identified and SGLT2I users were propensity score matched to other AGA users. The mean daily dose of loop diuretics in furosemide equivalents was ascertained. For those not on baseline loop diuretics, new use was compared between cohorts. For those on baseline loop diuretics, we assessed patterns of use (increased dose, decreased dose, stable dose, no longer using) at 12-months.

RESULTS

A total of 750 SGLT2I users were matched to 750 other AGA users. The distribution of loop diuretic use at mean doses of 0 mg (i.e., no use), ≤20 mg, >20 mg-40 mg, >40 mg-80 mg and >80 mg/day did not differ between cohorts at baseline or 12-months (p > 0.05 for both). SGLT2I use was associated with less new loop diuretic use (22.7% [79/348] vs. 34.0% [132/388]; p = 0.001). For those on loop diuretics at baseline (n = 764), patterns of use at 12-months did not differ between cohorts (p = 0.14).

CONCLUSIONS

New loop diuretic use was less frequent among SGLT2I users; however, patterns of loop diuretic use did not differ between cohorts in those on loop diuretics at baseline.

Heart failure in the patient with diabetes: Epidemiology, aetiology, prognosis, therapy and the effect of glucose-lowering medications

In people with type 2 diabetes the frequency of heart failure (HF) is increased and mortality from HF is higher than with non-diabetic HF. The increased frequency of HF is attributable to the cardiotoxic tetrad of ischaemic heart disease, left ventricular hypertrophy, diabetic cardiomyopathy and an extracellular volume expansion resistant to atrial natriuretic peptides. Activation of the renin-angiotensin-aldosterone system and sympathetic nervous systems results in cardiac remodelling, which worsens cardiac function. Reversal of remodelling can be achieved, and cardiac function improved in people with HF with reduced ejection fraction (HFrEF) by treatment with angiotensin-converting enzyme inhibitors and β-blockers. However, with HF with preserved ejection fraction (HFpEF), only therapy for the underlying risk factors helps. Blockers of mineralocorticoid receptors may be beneficial in both HFrEF and HFpEF. Glucose-lowering drugs can have a negative effect (insulin, sulphonylureas, dipeptidyl peptidase-4 inhibitors and thiazolidinediones), a neutral effect (α-glucosidase inhibitors and glucagon-like peptide-1 receptor agonists) or a positive effect (sodium-glucose co-transporter-2 inhibitors and metformin).

Inhibition of sodium-glucose cotransporter-2 preserves cardiac function during regional myocardial ischemia independent of alterations in myocardial substrate utilization

The goal of the present study was to evaluate the effects of SGLT2i on cardiac contractile function, substrate utilization, and efficiency before and during regional myocardial ischemia/reperfusion injury in normal, metabolically healthy swine. Lean swine received placebo or canagliflozin (300 mg PO) 24 h prior to and the morning of an invasive physiologic study protocol. Hemodynamic and cardiac function measurements were obtained at baseline, during a 30-min complete occlusion of the circumflex coronary artery, and during a 2-h reperfusion period. Blood pressure, heart rate, coronary flow, and myocardial oxygen consumption were unaffected by canagliflozin treatment. Ventricular volumes remained unchanged in controls throughout the protocol. At the onset of ischemia, canagliflozin produced acute large increases in left ventricular end-diastolic and systolic volumes which returned to baseline with reperfusion. Canagliflozin-mediated increases in end-diastolic volume were directly associated with increases in stroke volume and stroke work relative to controls during ischemia. Canagliflozin also increased cardiac work efficiency during ischemia relative to control swine. No differences in myocardial uptake of glucose, lactate, free fatty acids or ketones, were noted between treatment groups at any time. In separate experiments using a longer 60 min coronary occlusion followed by 2 h of reperfusion, canagliflozin increased end-diastolic volume and stroke volume and significantly diminished myocardial infarct size relative to control swine. These data demonstrate that SGLT2i with canagliflozin preserves cardiac contractile function and efficiency during regional myocardial ischemia and provides ischemia protection independent of alterations in myocardial substrate utilization.

Cardiovascular efficacy and safety of sodium-glucose co-transporter-2 inhibitors and glucagon-like peptide-1 receptor agonists: a systematic review and network meta-analysis

AIMS

To compare the cardiovascular efficacy and safety of sodium-glucose co-transporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs) in adults with Type 2 diabetes.

METHODS

Electronic databases were searched from inception to 22 October 2018 for randomized controlled trials designed to assess the cardiovascular efficacy of SGLT2 inhibitors or GLP-1RAs with regard to a three-point composite measure of major adverse cardiovascular events (non-fatal stroke, non-fatal myocardial infarction and cardiovascular mortality). Cardiovascular and safety data were synthesized using Bayesian network meta-analyses.

RESULTS

Eight trials, including 60 082 participants, were deemed eligible for the network meta-analysis. Both SGLT2 inhibitors [hazard ratio 0.86 (95% credible interval 0.74, 1.01]) and GLP-1RAs [hazard ratio 0.88 (95% credible interval 0.78, 0.98)] reduced the three-point composite measure compared to placebo, with no evidence of differences between them [GLP-1RAs vs SGLT2 inhibitors: hazard ratio 1.02 (95% credible interval 0.83, 1.23)]. SGLT2 inhibitors reduced risk of hospital admission for heart failure compared to placebo [hazard ratio 0.67 (95% credible interval 0.53, 0.85)] and GLP-1RAs [hazard ratio 0.71 (95% credible interval 0.53, 0.93)]. No differences were found between the two drug classes in non-fatal stroke, non-fatal myocardial infarction, cardiovascular mortality, all-cause mortality or safety outcomes.

CONCLUSIONS

SGLT2 inhibitors and GLP-1RAs reduced the three-point major adverse cardiovascular event risk compared to placebo, with no differences between them. Compared with GLP-1RAs and placebo, SGLT2 inhibitors led to a larger reduction in hospital admission for heart failure risk.

Molecular Mechanisms Responsible for Diastolic Dysfunction in Diabetes Mellitus Patients

In diabetic patients, cardiomyopathy is an important cause of heart failure, but its pathophysiology has not been completely understood thus far. Myocardial hypertrophy and diastolic dysfunction have been considered the hallmarks of diabetic cardiomyopathy (DCM), while systolic function is affected in the latter stages of the disease. In this article we propose the potential pathophysiological mechanisms responsible for myocardial hypertrophy and increased myocardial stiffness leading to diastolic dysfunction in this specific entity. According to our model, increased myocardial stiffness results from both cellular and extracellular matrix stiffness as well as cell–matrix interactions. Increased intrinsic cardiomyocyte stiffness is probably the most important contributor to myocardial stiffness. It results from the impairment in cardiomyocyte cytoskeleton. Several other mechanisms, specifically affected by diabetes, seem to also be significantly involved in myocardial stiffening, i.e., impairment in the myocardial nitric oxide (NO) pathway, coronary microvascular dysfunction, increased inflammation and oxidative stress, and myocardial sodium glucose cotransporter-2 (SGLT-2)-mediated effects. Better understanding of the complex pathophysiology of DCM suggests the possible value of drugs targeting the listed mechanisms. Antidiabetic drugs, NO-stimulating agents, anti-inflammatory agents, and SGLT-2 inhibitors are emerging as potential treatment options for DCM.

Stage-Based Management of Type 2 Diabetes Mellitus with Heart Failure

Type 2 diabetes negatively impacts heart failure outcomes. Insulin resistance, central adiposity, dyslipidemia, and altered cellular substrate metabolism each have a mechanistic role. Management strategies focused solely on glycemic control have had limited success. However, three new classes of drugs, each with several options, offer the promise of improved diabetes management in heart failure. Unlike earlier classes, these medications have had favorable cardiovascular outcomes. In this review, we present a therapeutic guide for metabolic treatment based on the stages of heart failure.

Direct cardiovascular impact of SGLT2 inhibitors: mechanisms and effects

Diabetes is a global epidemic and a leading cause of death with more than 422 million patients worldwide out of whom around 392 million alone suffer from type 2 diabetes (T2D). Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are novel and effective drugs in managing glycemia of T2D patients. These inhibitors gained recent clinical and basic research attention due to their clinically observed cardiovascular protective effects. Although interest in the study of various SGLT isoforms and the effect of their inhibition on cardiovascular function extends over the past 20 years, an explanation of the effects observed clinically based on available experimental data is not forthcoming. The remarkable reduction in cardiovascular (CV) mortality (38%), major CV events (14%), hospitalization for heart failure (35%), and death from any cause (32%) observed over a period of 2.6 years in patients with T2D and high CV risk in the EMPA-REG OUTCOME trial involving the SGLT2 inhibitor empagliflozin (Empa) have raised the possibility that potential novel, more specific mechanisms of SGLT2 inhibition synergize with the known modest systemic improvements, such as glycemic, body weight, diuresis, and blood pressure control. Multiple studies investigated the direct impact of SGLT2i on the cardiovascular system with limited findings and the pathophysiological role of SGLTs in the heart. The direct impact of SGLT2i on cardiac homeostasis remains controversial, especially that SGLT1 isoform is the only form expressed in the capillaries and myocardium of human and rodent hearts. The direct impact of SGLT2i on the cardiovascular system along with potential lines of future research is summarized in this review.

Clinical impact of oral antidiabetic medications in heart failure patients

Heart failure (HF) is a common complication in patients with type 2 diabetes and it is closely associated with high morbidity and mortality rate. The incidence of cardiovascular events in patients with diabetes is related to high levels of glycemia, expressed by increase of HbA1c levels. However, there is little evidence to indicate that glycemic control can reduce the incidence of HF events in this population. Recently, several new antidiabetic drugs have been proposed although the exact clinical impact on heart failure occurrence and deterioration is under debate. Most common oral antidiabetic medication such as SGLT2, GLP-1 receptor agonist, metformin, and DPP4 inhibitor revealed peculiar metabolic and biomolecular signal effects. Moreover, the negative effects of thiazolidinediones on HF prognosis, on cardiac function, and exercise tolerance is of great interest. Conversely, several studies on GLP-1RA have highlighted many positive effects on cardiac myocytes, reducing apoptosis through cAMP/PKA/CRCB-mediated pathways protecting against oxidative stress. DPP-4 inhibitors have a controversial effect: saxagliptin and alogliptin may increase the risk of HF as opposed to vildagliptin and sitagliptin. Metformin increases myocardial ATP levels due to activation of 5-AMPK and this could explain the positive link between the drug and events rate reduction in diabetic patients with HF. The more interesting class of new drugs is SGLT2 inhibitors, that seems to have a positive effect on cardiac function by 38% reduction of HF incidence and mortality with empagliflozin treatment. In this review, we would analyze the specific effects of each class so as to better elucidate the clinical impact of antidiabetic drug on HF for guiding the clinicians in the choice of a best individualized therapy.

Dehydration and insulinopenia are necessary and sufficient for euglycemic ketoacidosis in SGLT2 inhibitor-treated rats

Sodium-glucose transport protein 2 (SGLT2) inhibitors are a class of anti-diabetic agents; however, concerns have been raised about their potential to induce euglycemic ketoacidosis and to increase both glucose production and glucagon secretion. The mechanisms behind these alterations are unknown. Here we show that the SGLT2 inhibitor (SGLT2i) dapagliflozin promotes ketoacidosis in both healthy and type 2 diabetic rats in the setting of insulinopenia through increased plasma catecholamine and corticosterone concentrations secondary to volume depletion. These derangements increase white adipose tissue (WAT) lipolysis and hepatic acetyl-CoA content, rates of hepatic glucose production, and hepatic ketogenesis. Treatment with a loop diuretic, furosemide, under insulinopenic conditions replicates the effect of dapagliflozin and causes ketoacidosis. Furthermore, the effects of SGLT2 inhibition to promote ketoacidosis are independent from hyperglucagonemia. Taken together these data in rats identify the combination of insulinopenia and dehydration as a potential target to prevent euglycemic ketoacidosis associated with SGLT2i.

The use of sodium-glucose transport protein 2 (SGLT2) inhibitors for the treatment of diabetes has been associated with euglycemic ketoacidosis and increased glucose production and glucagon secretion. Here Perry et al. show that these effects rely on both insulinopenia and dehydration, and thus suggest ways to manage the side effects associated with the use of SGLT2 inhibitors.

The use of diuretics in heart failure with congestion - a position statement from the Heart Failure Association of the European Society of Cardiology

The vast majority of acute heart failure episodes are characterized by increasing symptoms and signs of congestion with volume overload. The goal of therapy in those patients is the relief of congestion through achieving a state of euvolaemia, mainly through the use of diuretic therapy. The appropriate use of diuretics however remains challenging, especially when worsening renal function, diuretic resistance and electrolyte disturbances occur. This position paper focuses on the use of diuretics in heart failure with congestion. The manuscript addresses frequently encountered challenges, such as (i) evaluation of congestion and clinical euvolaemia, (ii) assessment of diuretic response/resistance in the treatment of acute heart failure, (iii) an approach towards stepped pharmacologic diuretic strategies, based upon diuretic response, and (iv) management of common electrolyte disturbances. Recommendations are made in line with available guidelines, evidence and expert opinion.

Review on sodium-glucose cotransporter 2 inhibitor (SGLT2i) in diabetes mellitus and heart failure

SGLT-2 inhibitors are a novel class of anti-diabetic agents which act by inhibiting glucose reabsorption in proximal convoluted tubules of kidney. Apart from maintaining glucose homeostasis they exert a number of positive effects on the cardiovascular system like weight loss, decreasing blood pressure, preserving renal function, reducing triglycerides, natriuresis and improving endothelial dysfunction. In large clinical trials, all the three prototype agents – Empaglifozin, Canaglifozin and dapaglifozin have shown reductions in major adverse cardiovascular events including cardiovascular deaths, non fatal MI, stroke and heart failure (HF) hospitalizations. The reduction in heart failure hospitalization is a surprising finding and trials of these drug are now underway for HF also. More surprising is the fact that the benefits are comparable or even better that achieved by recently approved novel drugs for HF. In this review, we briefly discuss the pathophysiology of HF in diabetes, describe the prototype SGLT-2 molecules available, their data from large cardiovascular outcome trials till date and their role in current practice of diabetes management.

The metabolic model of heart failure: the role of sodium glucose co-transporter-2 (SGLT-2) inhibition

Heart failure (HF) is one of the leading causes of hospital readmissions and health care expenditures. With a vast degree of advancements in the clinical approach and diagnosis, its management protocol is limited in terms of enhancing quality of life and prognosis. Type 2 diabetes mellitus (T2DM) is considered as one of the commonly associated comorbid conditions in the HF population. The understanding of the molecular and metabolic models of HF has led to the utilization of therapeutic goals of T2DM in improving HF-related complications. In the recent era, SGLT-2 inhibitors have shown success in decreasing cardiovascular mortality in the T2DM population. This article will help the reviewer to comprehend the pathophysiology of HF and the potential role of SGLT-2 inhibitors in the management algorithm of HF and its associated risk factors in T2DM.

Mitochondrial dysfunction in pathophysiology of heart failure

Mitochondrial dysfunction has been implicated in the development of heart failure. Oxidative metabolism in mitochondria is the main energy source of the heart, and the inability to generate and transfer energy has long been considered the primary mechanism linking mitochondrial dysfunction and contractile failure. However, the role of mitochondria in heart failure is now increasingly recognized to be beyond that of a failed power plant. In this Review, we summarize recent evidence demonstrating vicious cycles of pathophysiological mechanisms during the pathological remodeling of the heart that drive mitochondrial contributions from being compensatory to being a suicide mission. These mechanisms include bottlenecks of metabolic flux, redox imbalance, protein modification, ROS-induced ROS generation, impaired mitochondrial Ca2+ homeostasis, and inflammation. The interpretation of these findings will lead us to novel avenues for disease mechanisms and therapy.

Diabetes-related cardiomyopathy: The sweet story of glucose overload from epidemiology to cellular pathways

Type 2 diabetes (T2D) is a major risk factor for heart failure (HF). Although the number of cases of myocardial infarction in the T2D population has been reduced by 25% over the last 10 years, the incidence of HF is continuously increasing, making it the most worrying diabetes complication. This strongly reinforces the urgent need for innovative therapeutic interventions to prevent cardiac dysfunction in T2D patients. To this end, epidemiological, imaging and animal studies have aimed to highlight the mechanisms involved in the development of diabetic cardiomyopathy. Epidemiological observations clearly show that hyperglycaemia correlates with severity of cardiac dysfunction and mortality in T2D patients. Both animal and cellular studies have demonstrated that, in the context of diabetes, the heart loses its ability to utilize glucose, therefore leading to glucose overload in cardiomyocytes that, in turn, promotes oxidative stress, accumulation of advanced glycation end-products (AGEs) and chronic activation of the hexosamine pathway. These have all been found to activate apoptosis and to alter heart contractility, calcium signalling and mitochondrial function. Although, in the past, tight glycaemic control has failed to improve cardiac function in T2D patients, recent clinical trials have reported cardiovascular benefit with hypoglycaemic antidiabetic drugs of the SGLT2-inhibitor family. This review, based on clinical evidence from mechanistic studies as well as several large clinical trials, covers 15 years of research, and strongly supports the idea that hyperglycaemia and glucose overload play a central role in the pathophysiology of diabetic cardiomyopathy.