Preventing and Treating Heart Failure with Sodium-Glucose Co-Transporter 2 Inhibitors

Efficacy and Safety of Sodium-Glucose Cotransporter 2 Inhibitors to Decrease the Risk of Cardiovascular Diseases: A Systematic Review

Cardiovascular disorders are one of the most frequent causes of death in people throughout the world. These disorders can account for the deaths of 31% of people worldwide. This systematic review examines the effectiveness of sodium-glucose cotransporter 2 (SGLT2) inhibitors in lowering the likelihood of cardiovascular diseases. The study aimed to evaluate various types of research, including randomized controlled trials and observational studies, to analyze how SGLT2 inhibitors impact cardiovascular disorders and establish evidence-based recommendations for clinical practice. The data in this research study were collected from 19 relevant published research articles. The key findings emphasized the potential advantages of SGLT2 inhibitors in reducing major cardiovascular disorders, such as myocardial infarction and stroke. Nonetheless, the study had certain limitations, including reliance on existing literature, exclusion of articles published prior to 2018, and restriction to English-language studies. Despite these limitations, this study contributed significantly to understanding the role of SGLT2 inhibitors in decreasing cardiovascular risk.

IncidenCe and predictOrs of heaRt fAiLure after acute coronarY Syndrome: The CORALYS registry

BACKGROUND

Previous studies investigating predictors of Heart Failure (HF) after acute coronary syndrome (ACS) were mostly conducted during fibrinolytic era or restricted to baseline characteristics and diagnoses prior to admission. We assessed the incidence and predictors of HF hospitalizations among patients treated with percutaneous coronary intervention (PCI) for ACS.

METHODS AND RESULTS

CORALYS is a multicenter, retrospective, observational registry including consecutive patients treated with PCI for ACS. Patients with known history of HF or reduced left ventricular ejection fraction (LVEF) were excluded. Incidence of HF hospitalizations was the primary endpoint. The composite of HF hospitalization or cardiovascular death, and cardiovascular and all-cause death were the secondary endpoints. Predictors of HF hospitalizations and the impact of HF hospitalization on cardiovascular and all-cause death were assessed by means of multivariable Cox proportional hazards model.14699 patients were included. After 2.9 ± 1.8 years, the incidence of HF hospitalizations was 12.7%. Multivariable analysis identified age, diabetes, chronic kidney disease, previous myocardial infarction, atrial fibrillation, pulmonary disease, GRACE risk-score ≥ 141, peripheral artery disease, cardiogenic shock at admission and LVEF ≤40% as independently associated with HF hospitalizations. Complete revascularization was associated with a lower risk of HF (HR 0.46,95%CI 0.39-0.55). HF hospitalization was associated with higher risk of CV and all-cause death (HR 1.89,95%CI 1.5-2.39 and HR 1.85,95%CI 1.6-2.14, respectively).

CONCLUSIONS

Incidence of HF hospitalizations among patients treated with PCI for ACS is not negligible and is associated with detrimental impact on patients' prognosis. Several variables may help to assess the risk of HF after ACS.

Management of cardiac diseases in liver transplant recipients: Comprehensive review and multidisciplinary practice-based recommendations

Cardiac diseases are one of the most common causes of morbidity and mortality following liver transplantation (LT). Prior studies have shown that cardiac diseases affect close to one-third of liver transplant recipients (LTRs) long term and that their incidence has been on the rise. This rise is expected to continue as more patients with advanced age and/or non-alcoholic steatohepatitis undergo LT. In view of the increasing disease burden, a multidisciplinary initiative was developed to critically review the existing literature (between January 1, 1990 and March 17, 2021) surrounding epidemiology, risk assessment, and risk mitigation of coronary heart disease, arrhythmia, heart failure, and valvular heart disease and formulate practice-based recommendations accordingly. In this review, the expert panel emphasizes the importance of optimizing management of metabolic syndrome and its components in LTRs and highlights the cardioprotective potential for the newer diabetes medications (e.g., sodium glucose transporter-2 inhibitors) in this high-risk population. Tailoring the multidisciplinary management of cardiac diseases in LTRs to the cardiometabolic risk profile of the individual patient is critical. The review also outlines numerous knowledge gaps to pave the road for future research in this sphere with the ultimate goal of improving clinical outcomes.

Mitochondrial Effects of Common Cardiovascular Medications: The Good, the Bad and the Mixed

Mitochondria are central organelles in the homeostasis of the cardiovascular system via the integration of several physiological processes, such as ATP generation via oxidative phosphorylation, synthesis/exchange of metabolites, calcium sequestration, reactive oxygen species (ROS) production/buffering and control of cellular survival/death. Mitochondrial impairment has been widely recognized as a central pathomechanism of almost all cardiovascular diseases, rendering these organelles important therapeutic targets. Mitochondrial dysfunction has been reported to occur in the setting of drug-induced toxicity in several tissues and organs, including the heart. Members of the drug classes currently used in the therapeutics of cardiovascular pathologies have been reported to both support and undermine mitochondrial function. For the latter case, mitochondrial toxicity is the consequence of drug interference (direct or off-target effects) with mitochondrial respiration/energy conversion, DNA replication, ROS production and detoxification, cell death signaling and mitochondrial dynamics. The present narrative review aims to summarize the beneficial and deleterious mitochondrial effects of common cardiovascular medications as described in various experimental models and identify those for which evidence for both types of effects is available in the literature.

Anti-Diabetic Therapy, Heart Failure and Oxidative Stress: An Update

Diabetes mellitus (DM) and heart failure (HF) are two chronic disorders that affect millions worldwide. Hyperglycemia can induce excessive generation of highly reactive free radicals that promote oxidative stress and further exacerbate diabetes progression and its complications. Vascular dysfunction and damage to cellular proteins, membrane lipids and nucleic acids can stem from overproduction and/or insufficient removal of free radicals. The aim of this article is to review the literature regarding the use of antidiabetic drugs and their role in glycemic control in patients with heart failure and oxidative stress. Metformin exerts a minor benefit to these patients. Thiazolidinediones are not recommended in diabetic patients, as they increase the risk of HF. There is a lack of robust evidence on the use of meglinitides and acarbose. Insulin and dipeptidyl peptidase-4 (DPP-4) inhibitors may have a neutral cardiovascular effect on diabetic patients. The majority of current research focuses on sodium glucose cotransporter 2 (SGLT2) inhibitors and glucagon-like peptide 1 (GLP-1) receptor agonists. SGLT2 inhibitors induce positive cardiovascular effects in diabetic patients, leading to a reduction in cardiovascular mortality and HF hospitalization. GLP-1 receptor agonists may also be used in HF patients, but in the case of chronic kidney disease, SLGT2 inhibitors should be preferred.

Sodium-Glucose Co-Transporter-2 Inhibitors and Cardiac Outcomes Among Patients Treated With Anthracyclines

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors improve outcomes among patients with established heart failure. Despite supportive basic science studies, there are no data on the value of SGLT2 inhibitors among patients treated with anthracyclines.

OBJECTIVES

This study sought to test the cardiac efficacy and overall safety of SGLT2 inhibitors in patients treated with anthracyclines.

METHODS

This study identified 3,033 patients with diabetes mellitus (DM) and cancer who were treated with anthracyclines. Cases were patients with cancer and DM who were on SGLT2 inhibitor therapy during anthracycline treatment (n = 32). Control participants (n = 96) were patients with cancer and DM who were also treated with anthracyclines, but were not on an SGLT2 inhibitor. The primary cardiac outcome was a composite of cardiac events (heart failure incidence, heart failure admissions, new cardiomyopathy [>10% decline in ejection fraction to <53%], and clinically significant arrhythmias). The primary safety outcome was overall mortality.

RESULTS

Age, sex, ethnicity, cancer type, cancer stage, and other cardiac risk factors were similar between groups. There were 20 cardiac events over a median follow-up period of 1.5 years. The cardiac event incidence was lower among case patients in comparison to control participants (3% vs 20%; P = 0.025). Case patients also experienced lower overall mortality when compared with control participants (9% vs 43%; P < 0.001) and a lower composite of sepsis and neutropenic fever (16% vs 40%; P = 0.013).

CONCLUSIONS

SGLT2 inhibitors were associated with lower rate of cardiac events among patients with cancer and DM who were treated with anthracyclines. Additionally, SGLT2 inhibitors appeared to be safe. These data support the conducting of a randomized clinical trial testing SGLT2 inhibitors in patients at high cardiac risk treated with anthracyclines.

Effects of Metoprolol Succinate Combined with Entresto on Cardiac Function Indexes and Coagulation Function in Patients with Congestive Heart Failure

Objective

To investigate the effects of metoprolol succinate combined with Entresto (Sacubitril Valsartan Sodium Tablets) on cardiac function and coagulation function in patients with congestive heart failure (CHF).

Methods

About 120 patients with CHF treated from April 2018 to April 2021 were enrolled in our hospital. The patients were arbitrarily assigned into control group and study group. The control group was cured with metoprolol succinate sustained-release tablets, and the study group was cured with metoprolol succinate sustained-release tablets combined with Entresto. The curative effect, cardiac function, vascular endothelial function, oxidative stress, and coagulation function were compared.

Results

First of all, we compared the general data, and there exhibited no difference in age, sex, course of disease, hypertension, coronary heart disease, diabetes, atrial fibrillation, and other general data (P > 0.05). Second, we compared the clinical efficacy. The effective rate of the study group (98.33%) was higher (90.00%) (P < 0.05). There exhibited no significant difference in cardiac function indexes before treatment, but after treatment, LVEF increased, LVESD and LVEDD decreased, LVESD and LVEDD in the study group were lower, and LVEF in the study group was higher (P < 0.05). Before treatment, there exhibited no significant difference in vascular endothelial function. However, the levels of CGRP and ET increased and the level of NO decreased, and the level of NO in the study group was lower, while the levels of CGRP and ET in the study group were higher after treatment (P < 0.05). There exhibited no significant difference in oxidative stress indexes before treatment, however, the levels of GSH-Px and SOD increased and the levels of MDA decreased after treatment, while the level of MDA in the study group was lower, while the levels of GSH-Px and SOD in the study group were higher (P < 0.05). Finally, we compared the indexes of blood coagulation function. There exhibited no significant difference before treatment, but after treatment, the levels of APTT, PT, and FIB decreased, and the levels of APTT, PT, and FIB in the study group were lower (P < 0.05).

Conclusion

Clinical practice demonstrated that LVESD and LVEDD decreased and LVEF increased after treatment with Entresto combined with metoprolol in CHF patients, which can effectively facilitate cardiac function and vascular endothelial function, reduce oxidative stress reaction, and improve blood coagulation indexes, suggesting that Entresto combined with metoprolol can improve ventricular remodeling with good safety.

A Conversation on an Effective, Straightforward, Quantitative Approach to the Outpatient Use of Insulin

For primary care providers, using insulin can present challenges that can be met by a straightforward approach using the following principles. Depending on when it is injected, each component of the insulin regimen has a maximal effect on a specific period of the 24-hour cycle (e.g., overnight, morning, afternoon, or evening). The glucose pattern in that period determines whether the dose of that component of the insulin regimen requires adjusting. Regarding which insulin types and insulin regimens to use, human insulin (NPH and regular) is as effective as analog insulins, and a two-injection intensified insulin regimen is as effective as a four-injection regimen.

Attenuation of Adverse Postinfarction Left Ventricular Remodeling with Empagliflozin Enhances Mitochondria-Linked Cellular Energetics and Mitochondrial Biogenesis

Sodium-glucose cotransporter 2 (SGLT2) inhibitors such as empagliflozin are known to reduce the risk of hospitalizations related to heart failure irrespective of diabetic state. Meanwhile, adverse cardiac remodeling remains the leading cause of heart failure and death in the USA. Thus, understanding the mechanisms that are responsible for the beneficial effects of SGLT2 inhibitors is of the utmost relevance and importance. Our previous work illustrated a connection between adverse cardiac remodeling and the regulation of mitochondrial turnover and cellular energetics using a short-acting glucagon-like peptide-1 receptor agonist (GLP1Ra). Here, we sought to determine if the mechanism of the SGLT2 inhibitor empagliflozin (EMPA) in ameliorating adverse remodeling was similar and/or to identify what differences exist, if any. To this end, we administered permanent coronary artery ligation to induce adverse remodeling in wild-type and Parkin knockout mice and examined the progression of adverse cardiac remodeling with or without EMPA treatment over time. Like GLP1Ra, we found that EMPA affords a robust attenuation of PCAL-induced adverse remodeling. Interestingly, unlike the GLP1Ra, EMPA does not require Parkin to improve/maintain mitochondria-related cellular energetics and afford its benefits against developing adverse remodeling. These findings suggests that further investigation of EMPA is warranted as a potential path for developing therapy against adverse cardiac remodeling for patients that may have Parkin and/or mitophagy-related deficiencies.

Exploring the Pleiotropic Genes and Therapeutic Targets Associated with Heart Failure and Chronic Kidney Disease by Integrating metaCCA and SGLT2 Inhibitors' Target Prediction

Background

Previous studies have shown that heart failure (HF) and chronic kidney disease (CKD) have common genetic mechanisms, overlapping pathophysiological pathways, and therapeutic drug—sodium-glucose cotransporter 2 (SGLT2) inhibitors.

Methods

The genetic pleiotropy metaCCA method was applied on summary statistics data from two independent meta-analyses of GWAS comprising more than 1 million people to identify shared variants and pleiotropic effects between HF and CKD. Targets of SGLT2 inhibitors were predicted by SwissTargetPrediction and DrugBank databases. To refine all genes, we performed using versatile gene-based association study 2 (VEGAS2) and transcriptome-wide association studies (TWAS) for HF and CKD, respectively. Gene enrichment and KEGG pathway analyses were used to explore the potential functional significance of the identified genes and targets.

Results

After metaCCA analysis, 4,624 SNPs and 1,745 genes were identified to be potentially pleiotropic in the univariate and multivariate SNP-multivariate phenotype analyses, respectively. 21 common genes were detected in both metaCCA and SGLT2 inhibitors' target prediction. In addition, 169 putative pleiotropic genes were identified, which met the significance threshold both in metaCCA analysis and in the VEGAS2 or TWAS analysis for at least one disease.

Conclusion

We identified novel variants associated with HF and CKD using effectively incorporating information from different GWAS datasets. Our analysis may provide new insights into HF and CKD therapeutic approaches based on the pleiotropic genes, common targets, and mechanisms by integrating the metaCCA method, TWAS and VEGAS2 analyses, and target prediction of SGLT2 inhibitors.

Diabetes Mellitus and Heart Failure

Diabetes mellitus (DM) is a major risk factor for new-onset heart failure (HF) and vice versa. The pathogenesis of new-onset HF in DM is complex and has been largely attributed to the toxic cardiovascular effects of hyperglycemia and relevant metabolic abnormalities (diabetic cardiomyopathy) as well as the frequently coexisting morbidities such as hypertension (HTN), coronary artery disease (CAD), and diabetic nephropathy. In patients with type 1 DM (T1DM), HF develops in the setting of a dysregulated immune response, whereas in most patients with type 2 DM (T2DM), against a background of overweight/obesity. HF prevention in DM is feasible with rigorous treatment of cardiovascular risk factors and selective antidiabetic agents. Conversely, development of new-onset T2DM in HF (cardiogenic DM) is common and has been attributed to an increase in the resistance to insulin, especially in the skeletal muscle, liver, and adipose tissue as well as in diminished insulin secretory response to hyperglycemia by pancreatic β-cells. Cardiogenic DM further deteriorates cardiac dysfunction and adversely affects outcome in HF. Novel lifesaving medications employed in HF management such as sacubitril/valsartan and sodium glucose cotransporter 2 inhibitors (SGLT-2i) have a favorable metabolic profile and lower the incidence of cardiogenic diabetes. Whether mitigation of cardiogenic DM should be a treatment target in HF deserves further investigation.

Imeglimin prevents heart failure with preserved ejection fraction by recovering the impaired unfolded protein response in mice subjected to cardiometabolic stress

The pathogenesis of heart failure with preserved ejection fraction (HFpEF) in obese diabetic patients has been implicated in metainflammation. Increased expression of inducible nitric oxide synthase (iNOS) and dysfunction of the unfolded protein response (UPR), especially inositol-requiring enzyme 1α-X-box binding protein 1 (IRE1α-Xbp1s) signaling in the heart, have been associated with HFpEF. We investigated the effect of imeglimin, a potential new treatment for type 2 diabetes, on the pathogenesis of HFpEF. We induced obesity, impaired glucose tolerance, and cardiac hypertrophy with fibrosis, fat accumulation, and diastolic dysfunction in wild-type mice with a high-fat diet (HFD) and the nitric oxide synthase (NOS) inhibitor l-NAME for 16 weeks. Treatment with imeglimin starting at 10 weeks not only improved their abnormal systemic glucose metabolism and visceral obesity but also their cardiac abnormalities. We found that imeglimin suppressed the upregulation of iNOS, and restored the expression of Xbp1s and the expression of the E3 ubiquitin ligase STIP1 homology and U-box-containing protein 1 (STUB1), which is responsible for the degradation of Forkhead box protein O1 (FoxO1), a direct transcriptional target of Xbp1s. It also suppressed the excessive transcriptional activity of FoxO1, which is located downstream of Xbp1s and is involved in the form development of HFpEF and cardiac adipogenesis. Imeglimin also restored the expression of Glutathione peroxidase 4 (GPX4), which protects cells against excess lipid peroxidation and governs a novel form of programmed cell death, called ferroptosis.

Evolution of Type 2 Diabetes Management from a Glucocentric Approach to Cardio-Renal Risk Reduction: The New Paradigm of Care

For many years, clinical studies could not show that lowering glucose in patients with type 2 diabetes leads to better macrovascular outcomes. In the past few years, new data have shown that treatment with two classes of dugs developed as "glucose-lowering agents," SGLT2 inhibitors and GLP-1 receptor agonists, can reduce macrovascular and renal complications. These studies have prompted debate about the main aim of type 2 diabetes management. In this review, three eras of diabetes management are described according to the treatment recommendations, such as the ADA/EASD consensus, moving from a pure glucocentric view into the present cardio-renal outcome-oriented approach, this has been endorsed by major diabetes and cardiology societies. While in the first era normalizing HbA_1c was the only focus (e.g., UK Prospective Diabetes Study), failing to show a reduction in cardiovascular morbidity and mortality, further studies analyzing the pros and cons of intensified control such as ACCORD, VADT, ADVANCE recognized that treatment intensification was associated with weight gain and hypoglycemia, thereby potentially reducing the benefits of glycemic control. Therefore, the focus in the second area was on controlling HbA_1c without these unwanted effects. The consistent beneficial results of several cardiovascular outcome trials with SGLT2 inhibitors and GLP-1 receptor agonists showing significantly improved cardio-renal outcomes, induced a paradigm shift: a change from (only) control of HbA_1c to an organ-protective approach with the main focus now on cardio-renal risk; this is now considered as the third era. Recent data indicating beneficial effects of glucose-lowering agents in particular SGLT2 inhibitors even in subjects without diabetes, improving hospitalization for heart failure and renal outcomes might reveal another new era, which could then be considered a fourth era. While current international guidelines call for this paradigm shift, registry data show that we are still far from translating this objective into real-world practice.

Chances and risks of sodium-glucose cotransporter 2 inhibitors in solid organ transplantation: A review of literatures

Solid organ transplantation offers life-saving treatment for patients with end-organ dysfunction. Patient survival and quality of life have improved over the past few decades as a result of pharmacological development, expansion of the donor pool, technological advances and standardization of practices related to transplantation. Still, transplantation is associated with cardiovascular complications, of which post-transplant diabetes mellitus (PTDM) is one of the most important. PTDM increases mortality, which is best documented in patients who have received kidney and heart transplants. PTDM results from traditional risk factors seen in patients with type 2 diabetes mellitus, but also from specific post-transplant risk factors such as metabolic side effects of immunosuppressive drugs, post-transplant viral infections and hypomagnesemia. Oral hypoglycaemic agents are the first choice for the treatment of type 2 diabetes mellitus in non-transplanted patients. However, the evidence on the safety and efficacy of oral hypoglycaemic agents in transplant recipients is limited. The favourable risk/benefit ratio, which is suggested by large-scale and long-term studies on new glucose-lowering drug classes such as glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, makes studies warranted to assess the potential role of these agents in the management of PTDM.

A Bioinformatics Investigation into the Pharmacological Mechanisms of Sodium-Glucose Co-transporter 2 Inhibitors in Diabetes Mellitus and Heart Failure Based on Network Pharmacology

PURPOSE

Diabetes mellitus (DM) is a major risk factor for the development of heart failure (HF). Sodium-glucose co-transporter 2 (SGLT2) inhibitors have demonstrated consistent benefits in the reduction of hospitalization for HF in patients with DM. However, the pharmacological mechanism is not clear. To investigate the mechanisms of SGLT2 inhibitors in DM with HF, we performed target prediction and network analysis by a network pharmacology method.

METHODS

We selected targets of SGLT2 inhibitors and DM status with HF from databases and studies. The "Drug-Target" and "Drug-Target-Disease" networks were constructed using Cytoscape. Then the protein-protein interaction (PPI) was analyzed using the STRING database. Gene Ontology (GO) biological functions and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed to investigate using the Bioconductor tool for analysis.

RESULTS

There were 125 effective targets between SGLT2 inhibitors and DM status with HF. Through further screening, 33 core targets were obtained, including SRC, MAPK1, NARS, MAPK3 and EGFR. It was predicted that the Rap1 signaling pathway, MAPK signaling pathway, EGFR tyrosine kinase inhibitor resistance, AGE-RAGE signaling pathway in diabetic complications and other signaling pathways were involved in the treatment of DM with HF by SGLT2 inhibitors.

CONCLUSION

Our study elucidated the possible mechanisms of SGLT2 inhibitors from a systemic and holistic perspective based on pharmacological networks. The key targets and pathways will provide new insights for further research on the pharmacological mechanism of SGLT2 inhibitors in the treatment of DM with HF.

Effects of SGLT2 inhibitors on cardiovascular, renal, and major safety outcomes in heart failure: A meta-analysis of randomized controlled trials

AIMS

Sodium-glucose co-transporter 2 inhibitor (SGLT2i), initially introduced for the treatment of diabetes mellitus (DM), demonstrates cardiovascular and renal benefits in patients with heart failure (HF). We aimed to conduct a meta-analysis of its effects on cardiovascular, renal, and major safety outcomes in HF.

METHODS AND RESULTS

PubMed, Embase, Cochrane Library, and Web of Science were searched using the terms of "SGLT2i and HF" or "SGLT2i *". Seven randomized, placebo-controlled trials comprising 14,113 HF patients (mean age, 66.0 years; female, 27.6%; DM, 58.9%) were included. SGLT2i treatment was associated with lower incidences (compared with placebo) of the composite outcomes of cardiovascular death or hospitalization for HF (HHF) (ratio risk [RR] 0.773; 95% confidence interval [CI], 0.719-0.831; p < 0.001; I² = 8.1%), cardiovascular death (RR 0.872; 95% CI, 0.788-0.964; p = 0.008; I² = 0.0%), HHF (RR 0.722; 95% CI, 0.657-0.793; p < 0.001; I² = 15.4%) and serious decrease in renal function (RR 0.673; 95% CI, 0.549-0.825; p < 0.001; I² = 17.7%). SGLT2i treatment was associated with a lower incidence of serious adverse events (SAEs) (RR 0.867; 95% CI, 0.808-0.930; p < 0.001; I² = 60.1%), but a higher incidence of volume depletion (RR 1.177; 95% CI, 1.040-1.333; p = 0.010; I² = 0.0%). Analysis on patients without DM showed consistent results, except for cardiovascular death.

CONCLUSION

SGLT2i treatment contributed to better cardiovascular and renal outcomes in patients with HF, regardless of the presence or absence of DM. SGLT2i also resulted in a lower incidence of SAEs, although a higher incidence of volume depletion was observed.

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.

Sodium-Glucose Cotransporter-2 (SGLT-2) Inhibitors: Benefits in Diabetics With Cardiovascular Disease

Optimal blood glucose control helps reduce the development of the complications of type II diabetes mellitus (T2DM). T2DM patients usually are at increased risk of cardiovascular (CV) events and mortality. Therapies and strategies to treat diabetes and its related CV outcomes still need more investigation to find the best management options for this population. Sodium-glucose cotransporter-2 (SGLT-2) inhibitors have several benefits over multiple organ systems of the human body. However, the comparative effectiveness of this drug class is still not well-established. Our review aims to assess SGLT-2 inhibitors' effects on the CV complications that occur because of uncontrolled diabetes.

A comprehensive literature search was conducted on PubMed and PubMed Central to find the relevant studies that were done from 2016 through 2020 to gather data for this review article. Those studies include reviews, randomized clinical trials, systematic reviews, and meta-analyses.

Studies used in this article found an associated decrease in CV complications and mortality in patients with T2DM who received treatment with SGLT-2 inhibitors compared to the placebo group. These drugs have shown significant efficacy and safety outcomes in diabetic patients with heart disease, as they are glycosuric and diuretics, both of which are characteristics that could provide benefits to this population.

SGLT-2 inhibitors appear to reduce the risk of cardiovascular events and mortality, suggesting that the benefits of these drugs seen in people with diabetes may apply to a broad population in the real world. We recommend further studies should confirm the immense clinical benefits with SGLT-2 inhibitors in patients with T2DM.

Glucose transporters in the kidney in health and disease

The kidneys filter large amounts of glucose. To prevent the loss of this valuable fuel, the tubular system of the kidney, particularly the proximal tubule, has been programmed to reabsorb all filtered glucose. The machinery involves the sodium-glucose cotransporters SGLT2 and SGLT1 on the apical membrane and the facilitative glucose transporter GLUT2 on the basolateral membrane. The proximal tubule also generates new glucose, particularly in the post-absorptive phase but also to enhance bicarbonate formation and maintain acid-base balance. The glucose reabsorbed or formed by the proximal tubule is primarily taken up into peritubular capillaries and returned to the systemic circulation or provided as an energy source to further distal tubular segments that take up glucose by basolateral GLUT1. Recent studies provided insights on the coordination of renal glucose reabsorption, formation, and usage. Moreover, a better understanding of renal glucose transport in disease states is emerging. This includes the kidney in diabetes mellitus, when renal glucose retention becomes maladaptive and contributes to hyperglycemia. Furthermore, enhanced glucose reabsorption is coupled to sodium retention through the sodium-glucose cotransporter SGLT2, which induces secondary deleterious effects. As a consequence, SGLT2 inhibitors are new anti-hyperglycemic drugs that can protect the kidneys and heart from failing. Recent studies discovered unique roles for SGLT1 with implications in acute kidney injury and glucose sensing at the macula densa. This review discusses established and emerging concepts of renal glucose transport, and outlines the need for a better understanding of renal glucose handling in health and disease.

Dapagliflozin for heart failure: is it a class effect?

Dapagliflozin, an SGLT2 inhibitor used in the management of Type 2 diabetes mellitus, has been recently approved for the control of worsening cardiovascular events, including deaths and hospitalizations, in adults with heart failure with reduced ejection fraction. Previously, canagliflozin had a label change with regards to its additional usage in the reduction of risk of hospitalization for heart failure in patients with both Type 2 diabetes mellitus and diabetic nephropathy with albuminuria. On the other hand, the therapeutic application of empagliflozin and ertugliflozin in heart failure is yet to be delineated comprehensively. The beneficial effects of these SGLT2 inhibitors, dapagliflozin in particular, in heart failure are found to be independent of neither the glucose-lowering nor the SGLT2 inhibiting effects.

The tubular hypothesis of nephron filtration and diabetic kidney disease

Kidney size and glomerular filtration rate (GFR) often increase with the onset of diabetes, and elevated GFR is a risk factor for the development of diabetic kidney disease. Hyperfiltration mainly occurs in response to signals passed from the tubule to the glomerulus: high levels of glucose in the glomerular filtrate drive increased reabsorption of glucose and sodium by the sodium-glucose cotransporters SGLT2 and SGLT1 in the proximal tubule. Passive reabsorption of chloride and water also increases. The overall capacity for proximal reabsorption is augmented by growth of the proximal tubule, which (alongside sodium-glucose cotransport) further limits urinary glucose loss. Hyperreabsorption of sodium and chloride induces tubuloglomerular feedback from the macula densa to increase GFR. In addition, sodium-glucose cotransport by SGLT1 on macula densa cells triggers the production of nitric oxide, which also contributes to glomerular hyperfiltration. Although hyperfiltration restores sodium and chloride excretion it imposes added physical stress on the filtration barrier and increases the oxygen demand to drive reabsorption. Tubular growth is associated with the development of a senescence-like molecular signature that sets the stage for inflammation and fibrosis. SGLT2 inhibitors attenuate the proximal reabsorption of sodium and glucose, normalize tubuloglomerular feedback signals and mitigate hyperfiltration. This tubule-centred model of diabetic kidney physiology predicts the salutary effect of SGLT2 inhibitors on hard renal outcomes, as shown in large-scale clinical trials.

Potential Mechanisms of Sodium-Glucose Co-Transporter 2 Inhibitor-Related Cardiovascular Benefits

The findings of recent clinical trials have shown that sodium-glucose co-transporter 2 (SGLT2) inhibitors produce effects beyond glucose lowering and have demonstrated beneficial cardiovascular effects that have been observed across a broad range of patients with type 2 diabetes mellitus. In particular, the cardiovascular benefit results largely from substantial and early effects of SGLT2 inhibition on cardiovascular death and hospitalization for heart failure. Recent cardiovascular outcomes trials (CVOTs) have also shown that relative risk reductions in cardiovascular outcomes were observed with SGLT2 inhibition both in patients with current and prior heart failure. Since the observed reductions of cardiovascular outcomes with SGLT2 inhibitor therapy were observed much earlier than would be expected by an anti-atherosclerotic effect, these results have led to speculation about the potential underlying pathways. Suggested mechanisms include natriuresis and osmotic diuresis; reductions in inflammation, oxidative stress, and arterial stiffness; reductions in blood pressure and body weight; and possible renoprotective effects. These effects could produce cardiovascular benefits through a range of cardiac effects, including reduction in left ventricular load, attenuation of cardiac fibrosis and inflammation, and improved myocardial energy production. Other possible mechanisms include inhibition of sodium-hydrogen exchange, increases in erythropoietin levels, and reduction in myocardial ischemia or reperfusion injury. It is likely that a range of mechanisms underlie the observed cardiovascular benefits of SGLT2 inhibitors; further elucidation of these mechanisms will be answered by ongoing research.