Sodium-Glucose Cotransporter 2 Inhibitors in Heart Failure

Association of common variant rs9934336 of SLC5A2 (SGLT2) gene with SARS-CoV-2 infection and mortality

COVID-19 has its life-threatening complications more pronounced in people with underlying health conditions such as diabetes, cardiovascular disease and kidney disease. Inhibition of the sodiumglucose cotransporter 2 (SGLT2), which primarily increases urinary glucose excretion, is shown to be beneficial in patients with type 2 diabetes mellitus (T2D) and other comorbidities. SGLT2 is encoded by SLC5A2 gene, and of the several genetic variants, SNP rs9934336 is gaining importance for being associated with reduced HbA1c level and lower incidence of T2D. Since a complex bidirectional relationship exists between COVID-19 and hyperglycaemia, we conducted a worldwide association study to investigate the effect of rs9934336 on COVID-19 outcomes. Worldwide prevalence data of SLC5A2 SNP rs9934336 were obtained from relevant published articles and databases for genomic variants. COVID-19 data procured from the Worldometer website were used for conducting Spearman’s correlation analysis with minor allele frequency data of rs9934336. Significant positive correlation was observed between rs9934336 and COVID-19 incidence (p < 0.0001, r = 0.6225) as well as deaths (p < 0.0001, r = 0.5837). The present finding of significant association of SLC5A2 variant rs9934336 with COVID-19 risk has to be validated by case–control studies in diverse populations along with other variants regulating the expression and function of SGLT2.

New insights into the molecular mechanisms of SGLT2 inhibitors on ventricular remodeling

Ventricular remodeling is a pathological process of ventricular response to continuous stimuli such as pressure overload, ischemia or ischemia-reperfusion, which can lead to the change of cardiac structure and function structure, which is central to the pathophysiology of heart failure (HF) and is an established prognostic factor in patients with HF. Sodium glucose cotransporter 2 inhibitors (SGLT2i) get a new hypoglycemic drug that inhibit sodium glucose coconspirator on renal tubular epithelial cells. Recently, clinical trials increasingly and animal experiments increasingly have shown that SGLT2 inhibitors have been largely applied in the fields of cardiovascular diseases, forinstance heart failure, myocardial ischemia-reperfusion injury, myocardial infarction, atrial fibrillation, metabolic diseases such as obesity, diabetes cardiomyopathy and other diseases play a cardiovascular protective role in addition to hypoglycemic. These diseases are association with ventricular remodeling. Inhibiting ventricular remodeling can improve the readmission rate and mortality of patients with heart failure. So far, clinical trials and animal experiments demonstrate that the protective effect of SGLT2 inhibitors in the cardiovascular field is bound to inhibit ventricular remodeling. Therefore, this review briefly investigates the molecular mechanisms of SGLT2 inhibitors on ameliorating ventricular remodeling, and further explore the mechanisms of cardiovascular protection of SGLT2 inhibitors, in order to establish strategies for ventricular remodeling to prevent the progress of heart failure.

Sodium–Glucose cotransporter 2 inhibitor empagliflozin decreases ventricular arrhythmia susceptibility by alleviating electrophysiological remodeling post-myocardial-infarction in mice

Background: Recent clinical trials indicate that sodium–glucose cotransporter 2 (SGLT2) inhibitors improve cardiovascular outcomes in myocardial infarction (MI) patients, but the underlying mechanisms remain unknown. As arrhythmia often occurs during myocardial infarction, it is the main cause of death.

Objective: The purpose of this study was to investigate the influence of empagliflozin (EMPA), an SGLT2 inhibitor, on cardiac electrophysiological remodeling and arrhythmia susceptibility of myocardial infarction mice.

Methods: ECG was obtained from mice 1 week after MI to determine the QT interval. In an electrophysiological study and optical mapping was performed to evaluate the function of EMPA and underlying mechanisms of post-myocardial-infarction in mice.

Results: EMPA treatment significantly reduced the QT interval of MI mice (MI + EMPA 50.24 ms vs. MI 64.68 ms). The membrane potential and intracellular Ca [Ca_i] were mapped from 13 MI hearts and five normal hearts using an optical mapping technique. A dynamic pacing protocol was used to determine action potential duration and [Ca_i] at baseline and after EMPA (10 umol/L) infusion. EMPA perfusion did not change the APD₈₀ and CaT₈₀ in normal ventricles while shortening them in an infarct zone, bordering zone, and remote zone of MI hearts at 200 ms, 150 ms, 120 ms, and 100 ms pacing cycle length. The conduction velocity of infarcted ventricles was 0.278 m/s and 0.533 m/s in normal ventricles at baseline (p < 0.05). After EMPA administration, the conduction velocity of infarcted ventricles increased to 0.363 m/s, whereas no significant changes were observed in normal ventricles. The action potential rise time, CaT rise time, and CaT tau time were improved after EMPA perfusion in infarcted ventricles, whereas no significant changes were observed in normal ventricles. EMPA decreases early afterdepolarizations premature ventricular beats, and ventricular fibrillation (VF) in infarcted ventricles. The number of phase singularities (baseline versus EMPA, 6.26 versus 3.25), dominant frequency (20.52 versus 10.675 Hz), and ventricular fibrillation duration (1.072 versus 0.361 s) during ventricular fibrillation in infarcted ventricles were all significantly decreased by EMPA.

Conclusion: Treatment with EMPA improved post-MI electrophysiological remodeling and decreased substrate for VF of MI mice. The inhibitors of SGLT2 may be a new class of agents for the prevention of ventricle arrhythmia after chronic MI.

Sodium-Glucose Cotransporter-2 Inhibitors Improve Cardiovascular Dysfunction in Type 2 Diabetic East Asians

In East Asians, the incidence of type 2 DM (T2DM) has increased as a result of major alterations in life. Cardiovascular problems are more likely in those with T2DM. Sodium-glucose cotransporter-2 (SGLT2) inhibitors are novel insulin-independent antihyperglycemic drugs that limit renal glucose reabsorption and thereby improve glycemic control. They are used alone or in combination with insulin and other antihyperglycemic medications to treat diabetes, and they are also helpful in protecting against the progression of complications. This review has evaluated the available evidence not only on the efficacy of SGLT2 inhibitors in T2DM, but also on their favourable cardiovascular events in East Asians. DM is an independent risk factor for cardiovascular diseases. As a result, in addition to glycemic control in diabetes management, the therapeutic goal in East Asian diabetic patients should be to improve adverse cardiovascular outcomes. Besides establishing antidiabetic effects, several studies have reported cardioprotective benefits of SGLT2 inhibitors via numerous pathways. SGLT2 inhibitors show promising antidiabetic drugs with potential cardiovascular advantages, given that a high number of diabetic patients in East Asia have co-existing cardiovascular disorders. Despite significant positive results in favour of SGLT2, more research is needed to determine how SGLT2 inhibitors exert these impressive cardiovascular effects.

Introduction to the Theme "New Insights, Strategies, and Therapeutics for Common Diseases"

The reviews in Volume 62 of the Annual Review of Pharmacology and Toxicology (ARPT) cover a diverse range of topics. A theme that encompasses many of these reviews is their relevance to common diseases and disorders, including type 2 diabetes, heart failure, cancer, tuberculosis, Alzheimer's disease, neurodegenerative disorders, and Down syndrome. Other reviews highlight important aspects of therapeutics, including placebos and patient-centric approaches to drug formulation. The reviews with this thematic focus, as well as other reviews in this volume, emphasize new mechanistic insights, experimental and therapeutic strategies, and novel insights regarding topics in the disciplines of pharmacology and toxicology. As the editors of ARPT, we believe that these reviews help advance those disciplines and, even more importantly, have the potential to improve the health care of the world's population. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 62 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.