Dapagliflozin acutely improves endothelial dysfunction, reduces aortic stiffness and renal resistive index in type 2 diabetic patients: a pilot study

Cardiovascular Benefits from Gliflozins: Effects on Endothelial Function

Type 2 diabetes mellitus (T2DM) is a known independent risk factor for atherosclerotic cardiovascular disease (CVD) and solid epidemiological evidence points to heart failure (HF) as one of the most common complications of diabetes. For this reason, it is imperative to consider the prevention of CV outcomes as an effective goal for the management of diabetic patients, as important as lowering blood glucose. Endothelial dysfunction (ED) is an early event of atherosclerosis involving adhesion molecules, chemokines, and leucocytes to enhance low-density lipoprotein oxidation, platelet activation, and vascular smooth muscle cell proliferation and migration. This abnormal vascular phenotype represents an important risk factor for the genesis of any complication of diabetes, contributing to the pathogenesis of not only macrovascular disease but also microvascular damage. Gliflozins are a novel class of anti-hyperglycemic agents used for the treatment of Type 2 diabetes mellitus (T2DM) that selectively inhibit the sodium glucose transporter 2 (SGLT2) in the kidneys and have provoked large interest in scientific community due to their cardiovascular beneficial effects, whose underlying pathophysiology is still not fully understood. This review aimed to analyze the cardiovascular protective mechanisms of SGLT2 inhibition in patients T2DM and their impact on endothelial function.

Effects of GLP-1 receptor agonists and SGLT-2 inhibitors on cardiac structure and function: a narrative review of clinical evidence

The impressive results of recent clinical trials with glucagon-like peptide-1 receptor agonists (GLP-1Ra) and sodium glucose transporter 2 inhibitors (SGLT-2i) in terms of cardiovascular protection prompted a huge interest in these agents for heart failure (HF) prevention and treatment. While both classes show positive effects on composite cardiovascular endpoints (i.e. 3P MACE), their actions on the cardiac function and structure, as well as on volume regulation, and their impact on HF-related events have not been systematically evaluated and compared. In this narrative review, we summarize and critically interpret the available evidence emerging from clinical studies. While chronic exposure to GLP-1Ra appears to be essentially neutral on both systolic and diastolic function, irrespective of left ventricular ejection fraction (LVEF), a beneficial impact of SGLT-2i is consistently detectable for both systolic and diastolic function parameters in subjects with diabetes with and without HF, with a gradient proportional to the severity of baseline dysfunction. SGLT-2i have a clinically significant impact in terms of HF hospitalization prevention in subjects at high and very high cardiovascular risk both with and without type 2 diabetes (T2D) or HF, while GLP-1Ra have been proven to be safe (and marginally beneficial) in subjects with T2D without HF. We suggest that the role of the kidney is crucial for the effect of SGLT-2i on the clinical outcomes not only because these drugs slow-down the time-dependent decline of kidney function and enhance the response to diuretics, but also because they attenuate the meal-related anti-natriuretic pressure (lowering postprandial hyperglycemia and hyperinsulinemia and preventing proximal sodium reabsorption), which would reduce the individual sensitivity to day-to-day variations in dietary sodium intake.

Effects of SGLT2 Inhibitors on Ion Homeostasis and Oxidative Stress associated Mechanisms in Heart Failure

Sodium-glucose cotransporter 2 (SGLT2) inhibitors present a class of antidiabetic drugs, which inhibit renal glucose reabsorption resulting in the elevation of urinary glucose levels. Within the past years, SGLT2 inhibitors have become increasingly relevant due to their effects beyond glycemic control in patients with type 2 diabetes (T2DM). Although dedicated large trials demonstrated cardioprotective effects of SGLT2 inhibitors, the exact mechanisms responsible for those benefits have not been fully identified. Alterations in Ca²⁺ signaling and oxidative stress accompanied by excessive reactive oxygen species (ROS) production, fibrosis and inflammatory processes form cornerstones of potential molecular targets for SGLT2 inhibitors. This review focused on three hypotheses for SGLT2 inhibitor-mediated cardioprotection: ion homeostasis, oxidative stress and endothelial dysfunction.

SGLT2 Inhibitors and Their Mode of Action in Heart Failure-Has the Mystery Been Unravelled?

PURPOSE OF REVIEW

SGLT2 inhibitors (SGLT2i) are new drugs for patients with heart failure (HF) irrespective of diabetes. However, the mechanisms of SGLT2i in HF remain elusive. This article discusses the current clinical evidence for using SGLT2i in different types of heart failure and provides an overview about the possible underlying mechanisms.

RECENT FINDINGS

Clinical and basic data strongly support and extend the use of SGLT2i in HF. Improvement of conventional secondary risk factors is unlikely to explain the prognostic benefits of these drugs in HF. However, different multidirectional mechanisms of SGLT2i could improve HF status including volume regulation, cardiorenal mechanisms, metabolic effects, improved cardiac remodelling, direct effects on cardiac contractility and ion-homeostasis, reduction of inflammation and oxidative stress as well as an impact on autophagy and adipokines. Further translational studies are needed to determine the mechanisms of SGLT2i in HF. However, basic and clinical evidence encourage the use of SGLT2i in HFrEF and possibly HFpEF.

Switch to SGLT2 Inhibitors and Improved Endothelial Function in Diabetic Patients with Chronic Heart Failure

PURPOSE

The use of sodium-glucose-cotransporter-type-2 inhibitors (SGLT2i) was associated in previous studies with an improved vascular function in non-human experimental models. We therefore sought to evaluate possible changes in endothelial function assessed by flow-mediated dilation (FMD) in patients with chronic heart failure (CHF) and type-2 diabetes mellitus (T2DM), switching from other oral hypoglycemic agents to SGLT2i in an observational study.

METHODS

Twenty-two consecutive outpatients with CHF and T2DM were enrolled after switching to SGLT2i therapy, and compared with 23 consecutive controls from the same registry comparable for principal clinical characteristics. In all patients, endothelial function was assessed by FMD at baseline and after 3 months of follow-up.

RESULTS

Three months of therapy with SGLT2i were associated with a statistically significant improvement in endothelial function (19.0 ± 5.7% vs 8.5 ± 4.1%, p < 0.0001); baseline levels of FMD were comparable between groups (p n.s.). Therapy with SGLT2i was significantly associated to improved FMD levels even at multivariable stepwise regression analysis (p < 0.001).

CONCLUSIONS

Switch to SGLT2i in patients with CHF and T2DM was associated in an observational non-randomized study with an improved endothelial function.

SGLT2-Inhibition reverts urinary peptide changes associated with severe COVID-19: An in-silico proof-of-principle of proteomics-based drug repurposing

Severe COVID‐19 is reflected by significant changes in urine peptides. Based on this observation, a clinical test predicting COVID‐19 severity, CoV50, was developed and registered as in vitro diagnostic in Germany. We have hypothesized that molecular changes displayed by CoV50, likely reflective of endothelial damage, may be reversed by specific drugs. Such an impact by a drug could indicate potential benefits in the context of COVID‐19. To test this hypothesis, urinary peptide data from patients without COVID‐19 prior to and after drug treatment were collected from the human urinary proteome database. The drugs chosen were selected based on availability of sufficient number of participants in the dataset (n > 20) and potential value of drug therapies in the treatment of COVID‐19 based on reports in the literature. In these participants without COVID‐19, spironolactone did not demonstrate a significant impact on CoV50 scoring. Empagliflozin treatment resulted in a significant change in CoV50 scoring, indicative of a potential therapeutic benefit. The study serves as a proof‐of‐principle for a drug repurposing approach based on human urinary peptide signatures. The results support the initiation of a randomized control trial testing a potential positive effect of empagliflozin for severe COVID‐19, possibly via endothelial protective mechanisms.

Dapagliflozin in patients with cardiometabolic risk factors hospitalised with COVID-19 (DARE-19): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

COVID-19 can lead to multiorgan failure. Dapagliflozin, a SGLT2 inhibitor, has significant protective benefits for the heart and kidney. We aimed to see whether this agent might provide organ protection in patients with COVID-19 by affecting processes dysregulated during acute illness.

METHODS

DARE-19 was a randomised, double-blind, placebo-controlled trial of patients hospitalised with COVID-19 and with at least one cardiometabolic risk factor (ie, hypertension, type 2 diabetes, atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease). Patients critically ill at screening were excluded. Patients were randomly assigned 1:1 to dapagliflozin (10 mg daily orally) or matched placebo for 30 days. Dual primary outcomes were assessed in the intention-to-treat population: the outcome of prevention (time to new or worsened organ dysfunction or death), and the hierarchial composite outcome of recovery (change in clinical status by day 30). Safety outcomes, in patients who received at least one study medication dose, included serious adverse events, adverse events leading to discontinuation, and adverse events of interest. This study is registered with ClinicalTrials.gov, NCT04350593.

FINDINGS

Between April 22, 2020 and Jan 1, 2021, 1250 patients were randomly assigned with 625 in each group. The primary composite outcome of prevention showed organ dysfunction or death occurred in 70 patients (11·2%) in the dapagliflozin group, and 86 (13·8%) in the placebo group (hazard ratio [HR] 0·80, 95% CI 0·58-1·10; p=0·17). For the primary outcome of recovery, 547 patients (87·5%) in the dapagliflozin group and 532 (85·1%) in the placebo group showed clinical status improvement, although this was not statistically significant (win ratio 1·09, 95% CI 0·97-1·22; p=0·14). There were 41 deaths (6·6%) in the dapagliflozin group, and 54 (8·6%) in the placebo group (HR 0·77, 95% CI 0·52-1·16). Serious adverse events were reported in 65 (10·6%) of 613 patients treated with dapagliflozin and in 82 (13·3%) of 616 patients given the placebo.

INTERPRETATION

In patients with cardiometabolic risk factors who were hospitalised with COVID-19, treatment with dapagliflozin did not result in a statistically significant risk reduction in organ dysfunction or death, or improvement in clinical recovery, but was well tolerated.

FUNDING

AstraZeneca.

Effects of Sodium-Glucose Co-Transporter 2 Inhibitors on Vascular Cell Function and Arterial Remodeling

Cardiovascular disease is the leading cause of morbidity and mortality in diabetes. Recent clinical studies indicate that sodium-glucose co-transporter 2 (SGLT2) inhibitors improve cardiovascular outcomes in patients with diabetes. The mechanism underlying the beneficial effect of SGLT2 inhibitors is not completely clear but may involve direct actions on vascular cells. SGLT2 inhibitors increase the bioavailability of endothelium-derived nitric oxide and thereby restore endothelium-dependent vasodilation in diabetes. In addition, SGLT2 inhibitors favorably regulate the proliferation, migration, differentiation, survival, and senescence of endothelial cells (ECs). Moreover, they exert potent antioxidant and anti-inflammatory effects in ECs. SGLT2 inhibitors also inhibit the contraction of vascular smooth muscle cells and block the proliferation and migration of these cells. Furthermore, studies demonstrate that SGLT2 inhibitors prevent postangioplasty restenosis, maladaptive remodeling of the vasculature in pulmonary arterial hypertension, the formation of abdominal aortic aneurysms, and the acceleration of arterial stiffness in diabetes. However, the role of SGLT2 in mediating the vascular actions of these drugs remains to be established as important off-target effects of SGLT2 inhibitors have been identified. Future studies distinguishing drug- versus class-specific effects may optimize the selection of specific SGLT2 inhibitors in patients with distinct cardiovascular pathologies.

Acute pleiotropic effects of dapagliflozin in type 2 diabetic patients with heart failure with reduced ejection fraction: a crossover trial

Aims

This study aimed to explore the rapid effects of dapagliflozin in heart failure with reduced ejection fraction (HFrEF).

Methods and results

We studied the functional, echocardiographic, electrophysiological, lung ultrasound, ambulatory blood pressure (BP), microvascular and macrovascular function, and biochemical effects of 2 week treatment with dapagliflozin in 19 type 2 diabetic HFrEF patients in a double‐blind, crossover, placebo‐controlled trial. Dapagliflozin had no significant effect on clinical, functional, or quality of life parameters. Dapagliflozin reduced systolic BP [114 (105, 131) vs. 106 (98, 113) mmHg, P < 0.01] and diastolic BP [71 (61, 78) vs. 62 (55, 70) mmHg, P < 0.01]. There was no effect on cardiac chamber size, ventricular systolic function, lung ultrasound, or arterial wave reflection. Dapagliflozin increased creatinine [117 (92, 129) vs. 122 (107, 135) μmol/L, P < 0.05] and haemoglobin [135 (118, 138) vs. 136 (123, 144) g/L, P < 0.05]. There was a reduction in ventricular ectopy [1.4 (0.1, 2.9) vs. 0.2 (0.1, 1.4) %, P < 0.05] and an increase in standard deviation of normal heart beat intervals [70 (58, 90) vs. 74 (62, 103), P < 0.05]. Unexpectedly, dapagliflozin increased high‐sensitivity troponin T [25 (19, 37) vs. 28 (20, 42) ng/L, P < 0.01] and reduced reactive hyperaemia index [1.29 (1.21, 1.56) vs. 1.40 (1.23, 1.84), P < 0.05].

Conclusions

After 2 weeks, while multiple parameters supported BP reduction and haemoconcentration with dapagliflozin, reduction in cardiac filling pressure, lung water, and functional improvement was not shown. Reduced ventricular ectopic burden suggests an early antiarrhythmic benefit. The small increase in troponin T and the reduction in the reactive hyperaemia index warrant further mechanistic exploration in this treatment of proven mortality benefit in HFrEF.

Vascular and metabolic effects of SGLT2i and GLP-1 in heart failure patients

Alterations of endothelial function, inflammatory activation, and nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway are involved in the pathophysiology of heart failure. Metabolic alterations have been studied in the myocardium of heart failure (HF) patients; alterations in ketone body and amino acid/protein metabolism have been described in patients affected by HF, as well as mitochondrial dysfunction and other modified metabolic signaling. However, their possible contributions toward cardiac function impairment in HF patients are not completely known. Recently, sodium-glucose co-transporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) have emerged as a new class of drugs designed to treat patients with type 2 diabetes (T2D), but have also been shown to be protective against HF-related events and CV mortality. To date, the protective cardiovascular effects of these drugs in patients with and without T2D are not completely understood and several mechanisms have been proposed. In this review, we discuss on vascular and metabolic effects of SGLT2i and GLP-1 in HF patients.

Potential Therapeutic Benefits of Sodium-Glucose Cotransporter 2 Inhibitors in the Context of Ischemic Heart Failure: A State-Of-The-Art Review

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a class of anti-diabetic agents that block the reabsorption of glucose in the proximal convoluted tubule of the nephron, thereby contributing to glycosuria and lowering blood glucose levels. SGLT2 inhibitors have been associated with improved cardiovascular outcomes in patients with diabetes, including a reduced risk of cardiovascular death and hospitalizations for heart failure. Recently, DAPA-HF and EMPEROR REDUCED trials showed the beneficial cardiovascular effect of SGLT2 inhibitors in patients with heart failure with consistently reduced ejection fraction (HFrEF) regardless of the presence of diabetes. Moreover, some exploratory studies suggested that these drugs improve Left Ventricular (LV) systolic function and oppose LV adverse remodeling in patients with HFrEF. However, the exact mechanisms that mediated for this benefit are not fully understood. Beyond glycemic control, enhanced natriuresis, increased erythropoiesis, improved endothelial function, changes in myocardial metabolism, anti-inflammatory and anti-oxidative properties may all play an active role in SGLT2 inhibitors' cardiovascular benefits. A deep understanding of the pathophysiological interplay is key to define which HF phenotype could benefit more from SGLT2 inhibitors. Current clinical evidence on the comparison of different HF etiologies is limited to posthoc subgroup analysis of DAPA-HF and EMPEROR-REDUCED, which showed similar outcomes in patients with or without ischemic HF. On the other hand, in earlier studies of patients suffering from diabetes, rates of classic ischemic endpoints, such as myocardial infarction, stroke or coronary revascularization, did not differ between patients treated with SGLT2 inhibitors or placebo. The aim of this review is to discuss whether SGLT2 inhibitors may improve prognosis in patients with ischemic HF, not only in terms of reducing re-hospitalizations and improving left ventricular function but also by limiting coronary artery disease progression and ischemic burden.

The Role of SGLT2 Inhibitors in Vascular Aging

Vascular aging is defined as organic and functional changes in blood vessels, in which decline in autophagy levels, DNA damage, MicroRNA (miRNA), oxidative stress, sirtuin, and apoptosis signal-regulated kinase 1 (ASK1) are integral thereto. With regard to vascular morphology, the increase in arterial stiffness, atherosclerosis, vascular calcification and high amyloid beta levels are closely related to vascular aging. Further closely related thereto, at the cellular level, is the aging of vascular endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Vascular aging seriously affects the health, economy and life of patients, but can be delayed by SGLT2 inhibitors through the improvement of vascular function. In the present article, a review is conducted of recent domestic and international progress in research on SGLT2 inhibitors,vascular aging and diseases related thereto, thereby providing theoretical support and guidance for further revealing the relationship between SGLT2 inhibitors and diseases related to vascular aging.

SGLT2 Inhibitors as Calorie Restriction Mimetics: Insights on Longevity Pathways and Age-Related Diseases

Sodium-glucose cotransporter-2 (SGLT2) inhibitors induce glycosuria, reduce insulin levels, and promote fatty acid oxidation and ketogenesis. By promoting a nutrient deprivation state, SGLT2 inhibitors upregulate the energy deprivation sensors AMPK and SIRT1, inhibit the nutrient sensors mTOR and insulin/IGF1, and modulate the closely linked hypoxia-inducible factor (HIF)-2α/HIF-1α pathways. Phosphorylation of AMPK and upregulation of adiponectin and PPAR-α favor a reversal of the metabolic syndrome which have been linked to suppression of chronic inflammation. Downregulation of insulin/IGF1 pathways and mTOR signaling from a reduction in glucose and circulating amino acids promote cellular repair mechanisms, including autophagy and proteostasis which confer cellular stress resistance and attenuate cellular senescence. SIRT1, another energy sensor activated by NAD+ in nutrient-deficient states, is reciprocally activated by AMPK, and can deacetylate and activate transcription factors, such as PCG-1α, mitochondrial transcription factor A (TFAM), and nuclear factor E2-related factor (NRF)-2, that regulate mitochondrial biogenesis. FOXO3 transcription factor which target genes in stress resistance, is also activated by AMPK and SIRT1. Modulation of these pathways by SGLT2 inhibitors have been shown to alleviate metabolic diseases, attenuate vascular inflammation and arterial stiffness, improve mitochondrial function and reduce oxidative stress-induced tissue damage. Compared with other calorie restriction mimetics such as metformin, rapamycin, resveratrol, and NAD+ precursors, SGLT2 inhibitors appear to be the most promising in the treatment of aging-related diseases, due to their regulation of multiple longevity pathways that closely resembles that achieved by calorie restriction and their established efficacy in reducing cardiovascular events and all-cause mortality. Evidence is compelling for the role of SGLT2 inhibitors as a calorie restriction mimetic in anti-aging therapeutics.

Emergence of SGLT2 Inhibitors as Powerful Antioxidants in Human Diseases

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of oral glucose-lowering agents. Apart from their glucose-lowering effects, large clinical trials assessing certain SGLT2 inhibitors have revealed cardiac and renal protective effects in non-diabetic patients. These excellent outcomes motivated scientists and clinical professionals to revisit their underlying mechanisms. In addition to the heart and kidney, redox homeostasis is crucial in several human diseases, including liver diseases, neural disorders, and cancers, with accumulating preclinical studies demonstrating the therapeutic benefits of SGLT2 inhibitors. In the present review, we aimed to update recent advances in the antioxidant roles of SGLT2 inhibitors in common but debilitating human diseases. We anticipate that this review will guide new research directions and novel therapeutic strategies for diabetes, cardiovascular diseases, nephropathies, liver diseases, neural disorders, and cancers in the era of SGLT2 inhibitors.

The Potential Roles of Osmotic and Nonosmotic Sodium Handling in Mediating the Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Heart Failure

Concomitant type 2 diabetes and chronic kidney disease increases the risk of heart failure. Recent studies demonstrate beneficial effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on chronic kidney disease progression and heart failure hospitalization in patients with and without diabetes. In addition to inhibiting glucose reabsorption, SGLT2 inhibitors decrease proximal tubular sodium reabsorption, possibly leading to transient natriuresis. We review the hypothesis that SGLT2 inhibitor’s natriuretic and osmotic diuretic effects mediate their cardioprotective effects. The degree to which these benefits are related to changes in sodium, independent of the kidney, is currently unknown. Aside from effects on osmotically active sodium, we explore the intriguing possibility that SGLT2 inhibitors could also modulate nonosmotic sodium storage. This alternative hypothesis is based on emerging literature that challenges the traditional 2-compartment model of sodium balance to provide support for a 3-compartment model that includes the binding of sodium to glycosaminoglycans, such as those in muscles and skin. This recent research on nonosmotic sodium storage, as well as direct cardiac effects of SGLT2 inhibitors, provides possibilities for other ways in which SGLT2 inhibitors might mitigate heart failure risk. Overall, we review the effects of SGLT2 inhibitors on sodium balance and sensitivity, cardiac tissue, interstitial fluid and plasma volume, and nonosmotic sodium storage.

SGLT2 inhibitors have cardiovascular benefits that include HF outcomes in patients with and without diabetes. Because the underlying mechanisms are only partly explained by improvements in BP, body weight, or glucose control, other mechanisms have been proposed. We focus here on a central role for effects on sodium as underlying the positive benefits of SGLT2 inhibitors in HF. We explore the new (although still unconfirmed) idea that SGLT2 inhibitors exert some of their positive effects by affecting nonosmotic sodium (ie, sodium bound to muscles and skin and not dissolved in the blood).

SGLT2 inhibitors have emerged as a class of drugs, previously prescribed for patients with T2D, that have in more recent years been shown to have substantial heart and kidney clinical benefits in patients with and without T2D.

The degree to which these benefits are related to kidney-independent changes in sodium homeostasis is currently unknown.

A better understanding of the nonosmotic mechanisms underpinning the benefits of SGLT2 inhibition on HF (with reduced or preserved left ventricular ejection fraction) may allow researchers to assess the effects of SGLT2 inhibitors in combination with other treatments that affect sodium balance.

Sodium-Glucose Cotransporter-2 Inhibitors in Vascular Biology: Cellular and Molecular Mechanisms

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are new antidiabetic drugs that reduce hyperglycemia by inhibiting the glucose reabsorption in renal proximal tubules. Clinical studies have shown that SGLT2 inhibitors not only improve glycemic control but also reduce major adverse cardiovascular events (MACE, cardiovascular and total mortality, fatal or nonfatal myocardial infarction or stroke) and hospitalization for heart failure (HF), and improve outcome in chronic kidney disease. These cardiovascular and renal benefits have now been confirmed in both diabetes and non-diabetes patients. The precise mechanism(s) responsible for the protective effects are under intensive investigation. This review examines current evidence on the cardiovascular benefits of SGLT2 inhibitors, with a special emphasis on the vascular actions and their potential mechanisms.

The Forgotten Antiproteinuric Properties of Diuretics

BACKGROUND

Although diuretics are one of the most widely used drugs by nephrologists, their antiproteinuric properties are not generally taken into consideration.

SUMMARY

Thiazide diuretics have been shown to reduce proteinuria by >35% in several prospective controlled studies, and these values are markedly increased when combined with a low-salt diet. Thiazide-like diuretics (indapamide and chlorthalidone) have shown similar effectiveness. The antiproteinuric effect of mineralocorticoid receptor antagonists (spironolactone, eplerenone, and finerenone) has been clearly established through prospective and controlled studies, and treatment with finerenone reduces the risk of chronic kidney disease progression in type-2 diabetic patients. The efficacy of other diuretics such as amiloride, triamterene, acetazolamide, or loop diuretics has been less explored, but different investigations suggest that they might share the same antiproteinuric properties of other diuretics that should be evaluated through controlled studies. Although the inclusion of sodium-glucose cotransporter-2 inhibitors (SGLT2i) among diuretics is a controversial issue, their renoprotective and cardioprotective properties, confirmed in various landmark trials, constitute a true revolution in the treatment of patients with kidney disease. Recent subanalyses of these trials have shown that the early antiproteinuric effect induced by SGLT2i predicts long-term preservation of kidney function. Key Message: Whether the early reduction in proteinuria induced by diuretics other than finerenone and SGLT2i, as summarized in this review, also translates into long-term renoprotection requires further prospective and observational studies. In any case, it is important for the clinician to be aware of the antiproteinuric properties of drugs so often used in daily clinical practice.

Impact of Sodium-Glucose Co-Transporter 2 Inhibitors on Cardiac Protection

Sodium–glucose co-transporter 2 (SGLT2) inhibitors have been approved as a new class of anti-diabetic drugs for type 2 diabetes mellitus (T2DM). The SGLT2 inhibitors reduce glucose reabsorption through renal systems, thus improving glycemic control in all stages of diabetes mellitus, independent of insulin. This class of drugs has the advantages of no clinically relevant hypoglycemia and working in synergy when combined with currently available anti-diabetic drugs. While improving sugar level control in these patients, SGLT2 inhibitors also have the advantages of blood-pressure improvement and bodyweight reduction, with potential cardiac and renal protection. In randomized control trials for patients with diabetes, SGLT2 inhibitors not only improved cardiovascular and renal outcomes, but also hospitalization for heart failure, with this effect extending to those without diabetes mellitus. Recently, dynamic communication between autophagy and the innate immune system with Beclin 1-TLR9-SIRT3 complexes in response to SGLT2 inhibitors that may serve as a potential treatment strategy for heart failure was discovered. In this review, the background molecular pathways leading to the clinical benefits are examined in this new class of anti-diabetic drugs, the SGLT2 inhibitors.

Cardiovascular Safety and Benefits of Noninsulin Antihyperglycemic Drugs for the Treatment of Type 2 Diabetes Mellitus: Part 2

Ideal drugs to improve outcomes in type 2 diabetes mellitus (T2DM) are those with antiglycemic efficacy, as well as cardiovascular safety that has to be determined in appropriately designed cardiovascular outcome trials as mandated by regulatory agencies. The more recent antihyperglycemic medications have shown promise with regards to cardiovascular disease (CVD) risk reduction in T2DM patients at a high cardiovascular risk. Sodium glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists are associated with better cardiovascular outcomes and mortality in T2DM patients than are dipeptidylpeptidase-4 inhibitors, leading to the Food and Drug Administration's approval of empagliflozin to reduce mortality, and of liraglutide to reduce CVD risk in high-risk T2DM patients. For heart failure outcomes, sodium glucose cotransporter-2 inhibitors are beneficial, while glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors are neutral. Ongoing and planned randomized controlled trials of these newer drugs should clarify the possibility of class effects and of CVD risk reduction benefits in low-moderate cardiovascular risk patients. While we eagerly await the results on ongoing studies, these medications should be appropriately prescribed in T2DM patients with baseline CVD or those at a high CVD risk after carefully evaluating the elevated risk for adverse events like gastrointestinal disturbances, bladder cancer, genital infections, and amputations. Studies to understand the pleotropic and novel pathophysiological mechanisms demonstrated by the sodium glucose cotransporter-2 inhibitors will shed light on the effects of the modulation of microvascular, inflammatory, and thrombotic milieu for improving the CVD risk in T2DM patients. This is part 2 of the series on noninsulin antihyperglycemic drugs for the treatment of T2DM.

Diabetes Mellitus, Arterial Stiffness and Cardiovascular Disease: Clinical Implications and the Influence of SGLT2i

Type 2 diabetes mellitus (T2DM) is a rapidly evolving global health issue associated with a markedly increased risk of cardiovascular (CV) morbidity and mortality. The hyperglycaemic milieu contributes to the development of CV complications via several pathological pathways, leading to increased arterial stiffness (AS), that can be considered as a predictor of CV events in patients with diabetes. The measurement of AS is increasingly used for the clinical assessment of patients. Several methodologies were used in extensive population studies to assess AS; the most commonly used is the pulse wave velocity (PWV). The cardio-ankle vascular index (CAVI) was developed to measure AS; it is not affected by blood pressure at the time of measurement and shows stable values in healthy persons for years. There are several potential pharmacological and non-pharmacological interventions aiming to reduce AS. Recent evidence from clinical trials suggests that newer antidiabetic drugs do not only exert glycaemic-lowering properties but also decrease CV risk. In this context, sodium glucose cotransporter- 2 inhibitors (SGLT2i) ( empagliflozin, canagliflozin and dapagliflozin) significantly reduced the risk of CV and all-cause mortality (only EMPA-REG OUTCOME study) and hospitalization for heart failure in patients with T2DM with established CV disease and/or with CV risk factors. Improved endothelial function and AS probably represents one of the mechanisms by which these drugs exert their beneficial effects. The present review aimed both to describe the association between AS and T2DM and to discuss the effectiveness of SGLT2i on vascular endothelial dysfunction and AS.

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.

Sodium-Glucose Co-transporter-2 Inhibitors and Nephroprotection in Diabetic Patients: More Than a Challenge

Diabetic nephropathy is the most common cause of end-stage renal disease worldwide. Control of blood glucose and blood pressure (BP) reduces the risk of developing this complication, but once diabetic nephropathy is established, it is then only possible to slow its progression. Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are a novel class of oral hypoglycemic agents that increase urinary glucose excretion by suppressing glucose reabsorption at the renal proximal tubule. SGLT2is lower glycated hemoglobin (HbA1c) without increasing the risk of hypoglycemia, induce weight loss and improve various metabolic parameters including BP, lipid profile, albuminuria and uric acid. Several clinical trials have shown that SGLT2is (empagliflozin, dapagliflozin canagliflozin, and ertugliflozin) improve cardiovascular and renal outcomes and mortality in patients with type 2 diabetes. Effects of SGLT2is on the kidney can be explained by multiple pathways. SGLT2is may improve renal oxygenation and intra-renal inflammation thereby slowing the progression of kidney function decline. Additionally, SGLT2is are associated with a reduction in glomerular hyperfiltration, an effect which is mediated by the increase in natriuresis, the re-activation of tubule-glomerular feedback and independent of glycemic control. In this review, we will focus on renal results of major cardiovascular and renal outcome trials and we will describe direct and indirect mechanisms through which SGLT2is confer renal protection.

Chlorthalidone versus hydrochlorothiazide: major cardiovascular events, blood pressure, left ventricular mass, and adverse effects

BACKGROUND

There is continuous debate whether chlorthalidone (CTD) and hydrochlorothiazide (HCTZ) differ in reducing major cardiovascular events (MACE). HCTZ is prescribed 10 times more commonly than CTD.

METHOD

A systematic literature search yielded 14 references, including two network meta-analyses of randomized trials with MACE and left ventricular mass as outcomes.

RESULTS

The network meta-analysis of randomized trials showed CTD reducing MACE more than HCTZ, hazard ratio = 0.79 (0.72-0.88), P < 0.0001, and an observational cohort study gave an identical point estimate: hazard ratio = 0.79 (0.68-0.92), P = 0.002. In contrast, two observational cohort studies reported no differences between CTD and HCTZ. However, in the studies showing the superiority of CTD median follow-up was 4.3 and 7.0 years, respectively, whereas in the latter studies showing no difference between the two drugs follow-up was only 0.95 and 0.25 years. As differences in outcomes for MACE in hypertension trials with various interventions only emerge after prolonged (>1 year) therapy, differences in follow-up explain these discrepant results. CTD also more effectively reduced left ventricular mass in observational data and network analysis of trials. These advantages of CTD over HCTZ are consistent with greater reductions in night-time blood pressure, greater reductions in oxidative stress and platelet aggregation, and greater improvements in endothelial function.

CONCLUSION

Over the short-term there were no differences in the net clinical benefit between HCTZ and CTD. However, long-term available data document CTD to be significantly more effective in reducing MACE than HCTZ. The Veterans Administration's trial in progress may provide definitive answer to these questions.

Impact of SGLT2 Inhibitors on Heart Failure: From Pathophysiology to Clinical Effects

Heart failure (HF) affects up to over 20% of patients with type 2 diabetes (T2DM), even more in the elderly. Although, in T2DM, both hyperglycemia and the proinflammatory status induced by insulin resistance are crucial in cardiac function impairment, SGLT2i cardioprotective mechanisms against HF are several. In particular, these beneficial effects seem attributable to the significant reduction of intracellular sodium levels, well-known to exert a cardioprotective role in the prevention of oxidative stress and consequent cardiomyocyte death. From a molecular perspective, patients’ exposure to gliflozins’ treatment mimics nutrient and oxygen deprivation, with consequent autophagy stimulation. This allows to maintain the cellular homeostasis through different degradative pathways. Thus, since their introduction in the clinical practice, the hypotheses on SGLT2i mechanisms of action have changed: from simple glycosuric drugs, with consequent glucose lowering, erythropoiesis enhancing and ketogenesis stimulating, to intracellular sodium-lowering molecules. This provides their consequent cardioprotective effect, which justifies its significant reduction in CV events, especially in populations at higher risk. Finally, the updated clinical evidence of SGLT2i benefits on HF was summarized. Thus, this review aimed to analyze the cardioprotective mechanisms of sodium glucose transporter 2 inhibitors (SGLT2i) in patients with HF, as well as their clinical impact on cardiovascular events.

Rationale and design of the randomised controlled cross-over trial: Cardiovascular effects of empaglifozin in diabetes mellitus

BACKGROUND

Type 2 diabetes (T2D) is associated with an increased risk of cardiovascular (CV) disease. In patients with T2D and established CV disease, selective inhibitors of sodium-glucose cotransporter 2 (SGLT2) have been shown to decrease CV and all-cause mortality, and heart failure (HF) admissions. Utilising CV magnetic resonance imaging (CMR) and continuous glucose monitoring (CGM) by FreeStyle Libre Pro Sensor, we aim to explore the mechanisms of action which give Empagliflozin, an SGLT2 inhibitor, its beneficial CV effects and compare these to the effects of dipeptidyl peptidase-4 inhibitor Sitagliptin.

METHODS

This is a single centre, open-label, cross-over trial conducted at the Leeds Teaching Hospitals NHS Trust. Participants are randomised for the order of treatment and receive 3 months therapy with Empagliflozin, and 3 months therapy with Sitagliptin sequentially. Twenty-eight eligible T2D patients with established ischaemic heart disease will be recruited. Patients undergo serial CMR scans on three visits.

DISCUSSION

The primary outcome measure is the myocardial perfusion reserve in remote myocardium. We hypothesise that Empaglifozin treatment is associated with improvements in myocardial blood flow and reductions in myocardial interstitial fibrosis, independent of CGM measured glycemic control in patients with T2D and established CV disease.

TRIAL REGISTRATION

This study has full research ethics committee approval (REC: 18/YH/0190) and data collection is anticipated to finish in December 2021. This study was retrospectively registered at https://doi.org/10.1186/ISRCTN82391603 and monitored by the University of Leeds. The study results will be submitted for publication within 6 months of completion.

Sodium-glucose transporter inhibition in heart failure: from an unexpected side effect to a novel treatment possibility

Sodium-glucose transporter-2 inhibitors (SGLT2i), originally launched as glucose-lowering drugs, have been studied in large cardiovascular outcome trials to ascertain safety. Surprisingly, these compounds reduced the risk of cardiovascular events (cardiovascular death, non-fatal myocardial and non-fatal stroke) and total mortality. The mechanisms behind this benefit are only partly understood, but a major contributor is the reduction of heart failure hospitalisations, evident already within weeks after the initiation of the SGLT2i. SGLT2 inhibition increases urinary glucose excretion, thereby improving glycaemic control in an insulin-independent manner. Moreover, SGLT2i potentially impact the cardiovascular system both indirectly via weight loss and blood pressure lowering and directly through osmotic diuresis and increased sodium excretion and presumably by improving myocardial energetics. The aim of this review is to summarise evidence from all major outcome trials investigating SGLT2i in patients with diabetes, as well as recent evidence from trials in heart failure patients without glucose perturbations, which pave the way for novel treatment of large groups of patients. The results of these studies have been taken into account in recently issued guidelines for the management of diabetes and cardiovascular disease. An important task for diabetologists, cardiologists and general practitioners is to incorporate them into clinical practice to the benefit of many patients.

Endothelin antagonism and sodium glucose Co-transporter 2 inhibition. A potential combination therapeutic strategy for COVID-19

The novel coronavirus 2019 (COVID-19) infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global pandemic that requires a multi-faceted approach to tackle this unprecedent health crisis. Therapeutics to treat COVID-19 are an integral part of any such management strategy and there is a substantial unmet need for treatments for individuals most at risk of severe disease. This perspective review provides rationale of a combined therapeutic regimen of selective endothelin-A (ET-A) receptor antagonism and sodium glucose co-transporter-2 (SGLT-2) inhibition to treat COVID-19. Endothelin is a potent vasoconstrictor with pro-inflammatory and atherosclerotic effects. It is upregulated in a number of conditions including acute respiratory distress syndrome and cardiovascular disease. Endothelin mediates vasocontractility via endothelin (ET-A and ET-B) receptors on vascular smooth muscle cells (VSMCs). ET-B receptors regulate endothelin clearance and are present on endothelial cells, where in contrast to their role on VSMCs, mediate vasodilation. Therefore, selective endothelin-A (ET-A) receptor inhibition is likely the optimal approach to attenuate the injurious effects of endothelin and may reduce ventilation-perfusion mismatch and pulmonary inflammation, whilst improving pulmonary haemodynamics and oxygenation. SGLT-2 inhibition may dampen inflammatory cytokines, reduce hyperglycaemia if present, improve endothelial function, cardiovascular haemodynamics and cellular bioenergetics. This combination therapeutic approach may therefore have beneficial effects to mitigate both the pulmonary, metabolic and cardiorenal manifestations of COVID-19. Given these drug classes include medicines licensed to treat heart failure, diabetes and pulmonary hypertension respectively, information regarding their safety profile is established. Randomised controlled clinical trials are the best way to determine efficacy and safety of these medicines in COVID-19.

Cardiovascular benefits of sodium-glucose cotransporter 2 inhibitors in diabetic and nondiabetic patients

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) were developed as antidiabetic agents, but accumulating evidence has shown their beneficial effects on the cardiovascular system. Analyses of the EMPA-REG OUTCOME trial (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) suggested that these benefits are independent of glycemic control. Several large-scale outcome trials of SGLT2i also showed cardiovascular benefits in nondiabetic patients, strengthening this perspective. Extensive animal and clinical studies have likewise shown that mechanisms other than the antihyperglycemic effect underlie the cardiovascular benefits. Recent clinical guidelines recommend the use of SGLT2i in patients with type 2 diabetes mellitus and cardiovascular diseases because of the proven cardiovascular protective effects. Since the cardiovascular benefits are independent of glycemic control, the therapeutic spectrum of SGLT2i will likely be extended to nondiabetic patients.

Arterial Stiffness and Cardiovascular Risk in Hypertension

Arterial stiffness, a leading marker of risk in hypertension, can be measured at material or structural levels, with the latter combining effects of the geometry and composition of the wall, including intramural organization. Numerous studies have shown that structural stiffness predicts outcomes in models that adjust for conventional risk factors. Elastic arteries, nearer to the heart, are most sensitive to effects of blood pressure and age, major determinants of stiffness. Stiffness is usually considered as an index of vascular aging, wherein individuals excessively affected by risk factor exposure represent early vascular aging, whereas those resistant to risk factors represent supernormal vascular aging. Stiffness affects the function of the brain and kidneys by increasing pulsatile loads within their microvascular beds, and the heart by increasing left ventricular systolic load; excessive pressure pulsatility also decreases diastolic pressure, necessary for coronary perfusion. Stiffness promotes inward remodeling of small arteries, which increases resistance, blood pressure, and in turn, central artery stiffness, thus creating an insidious feedback loop. Chronic antihypertensive treatments can reduce stiffness beyond passive reductions due to decreased blood pressure. Preventive drugs, such as lipid-lowering drugs and antidiabetic drugs, have additional effects on stiffness, independent of pressure. Newer anti-inflammatory drugs also have blood pressure independent effects. Reduction of stiffness is expected to confer benefit beyond the lowering of pressure, although this hypothesis is not yet proven. We summarize different steps for making arterial stiffness measurement a keystone in hypertension management and cardiovascular prevention as a whole.

Effects of dapagliflozin on prevention of major clinical events and recovery in patients with respiratory failure because of COVID-19: Design and rationale for the DARE-19 study

AIMS

Coronavirus disease 2019 (COVID-19) is caused by a novel severe acute respiratory syndrome coronavirus 2. It can lead to multiorgan failure, including respiratory and cardiovascular decompensation, and kidney injury, with significant associated morbidity and mortality, particularly in patients with underlying metabolic, cardiovascular, respiratory or kidney disease. Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, has shown significant cardio- and renoprotective benefits in patients with type 2 diabetes (with and without atherosclerotic cardiovascular disease), heart failure and chronic kidney disease, and may provide similar organ protection in high-risk patients with COVID-19.

MATERIALS AND METHODS

DARE-19 (NCT04350593) is an investigator-initiated, collaborative, international, multicentre, randomized, double-blind, placebo-controlled study testing the dual hypotheses that dapagliflozin can reduce the incidence of cardiovascular, kidney and/or respiratory complications or all-cause mortality, or improve clinical recovery, in adult patients hospitalized with COVID-19 but not critically ill on admission. Eligible patients will have ≥1 cardiometabolic risk factor for COVID-19 complications. Patients will be randomized 1:1 to dapagliflozin 10 mg or placebo. Primary efficacy endpoints are time to development of new or worsened organ dysfunction during index hospitalization, or all-cause mortality, and the hierarchical composite endpoint of change in clinical status through day 30 of treatment. Safety of dapagliflozin in individuals with COVID-19 will be assessed.

CONCLUSIONS

DARE-19 will evaluate whether dapagliflozin can prevent COVID-19-related complications and all-cause mortality, or improve clinical recovery, and assess the safety profile of dapagliflozin in this patient population. Currently, DARE-19 is the first large randomized controlled trial investigating use of sodium-glucose cotransporter 2 inhibitors in patients with COVID-19.

Dapagliflozin effect on endothelial dysfunction in diabetic patients with atherosclerotic disease: a randomized active-controlled trial

Background

The glucose-lowering independent effect of sodium glucose cotransporter-2 inhibitors (SGLT2i) on arterial wall function has not yet been clarified. This study aims to assess whether SGLT2i treatment can attenuate endothelial dysfunction related to type 2 diabetes mellitus (T2D) compared with glucose-lowering equivalent therapy.

Methods

In a prospective, open-label, single-center, randomized clinical trial, 98 patients with T2DM and carotid intima-media thickness above the 75th percentile were randomized 1:1 to 12 weeks of therapy with dapagliflozin or glibenclamide in addition to metformin in glucose-lowering equivalent regimens. The coprimary endpoints were 1-min flow-mediated dilation (FMD) at rest and 1-min FMD after 15 min of ischemia followed by 15 min of reperfusion time (I/R).

Results

Ninety-seven patients (61% males, 57 ± 7 years) completed the study. The median HbA1c decreased by − 0.8 (0.7)% and -0.7 (0.95)% following dapagliflozin and glibenclamide, respectively. The first coprimary endpoint, i.e., rest FMD changed by + 3.3(8.2)% and − 1.2(7.5)% for the dapagliflozin and glibenclamide arms, respectively (p = 0.0001). Differences between study arms in the second coprimary endpoint were not significant. Plasma nitrite 1 min after rest FMD was higher for dapagliflozin [308(220) nmol/L] than for glibenclamide (258[110] nmol/L; p = 0.028). The resistive indices at 1 min [0.90 (0.11) vs. 0.93 (0.07); p = 0.03] and 5 min [0.93 (0.07) vs. 0.95 (0.05); p = 0.02] were higher for the glibenclamide group than for the dapagliflozin group. Plasma biomarkers for inflammation and oxidative stress did not differ between the treatments.

Conclusions

Dapagliflozin improved micro- and macrovascular endothelial function compared to glibenclamide, regardless of glycemic control in patients with T2DM and subclinical carotid atherosclerotic disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01264-z.

Glomerular Endothelial Cell Crosstalk With Podocytes in Diabetic Kidney Disease

Diabetes is the main cause of renal failure worldwide. Complications of the kidney micro-and macro-circulation are common in diabetic patients, leading to proteinuria and can progress to end-stage renal disease. Across the complex interplays aggravating diabetes kidney disease progression, lesions of the glomerular filtration barrier appear crucial. Among its components, glomerular endothelial cells are known to be central safeguards of plasma filtration. An array of evidence has recently pinpointed its intricate relations with podocytes, highly specialized pericytes surrounding glomerular capillaries. During diabetic nephropathy, endothelial cells and podocytes are stressed and damaged. Besides, each can communicate with the other, directly affecting the progression of glomerular injury. Here, we review recent studies showing how in vitro and in vivo studies help to understand pathological endothelial cells-podocytes crosstalk in diabetic kidney disease.

Hypertension: Current trends and future perspectives

Hypertension is a significant and increasing global health issue. It is a leading cause of cardiovascular disease and premature death worldwide due to its effects on end organs, and through its associations with chronic kidney disease, diabetes mellitus and obesity. Despite current management strategies, many patients do not achieve adequate blood pressure (BP) control. Hypertension-related cardiovascular mortality rates are rising in tandem with the increasing global prevalence of chronic kidney disease, diabetes mellitus and obesity. Improving BP control must therefore be urgently prioritised. Strategies include utilising existing antihypertensive agents more effectively, and using treatments developed for co-existing conditions (such as sodium-glucose cotransporter 2 inhibitors for diabetes mellitus) that offer additional BP-lowering and cardiovascular benefits. Additionally, novel therapeutic agents that target alternative prohypertensive pathways and that offer broader cardiovascular protection are under development, including dual angiotensin receptor-neprilysin inhibitors. Nonpharmacological strategies such as immunotherapy are also being explored. Finally, advancing knowledge of the human genome and molecular modification technology may usher in an exciting new era of personalised medicine, with the potential to revolutionise the management of hypertension.

Endothelial function and dysfunction: Impact of sodium-glucose cotransporter 2 inhibitors

Diabetes mellitus is associated with endothelial dysfunction that leads to cardiovascular complications. Sodium-glucose cotransporter 2 (SGLT2) inhibitors demonstrated efficacy in glycemic control in type 2 diabetes patients with positive cardiovascular outcome. Recent research revealed a link between SGLT2 inhibition and improved macro- and microvascular endothelial functions. Mechanisms underlying this phenomenon could be due to the role of SLGT2 in the regulation of endothelial physiology. In this review, current knowledge and hypothesis on the link between SGLT2 and endothelial function were critically appraised and the impact of SGLT2 inhibitors on endothelial dysfunction in pre-clinical and clinical studies was discussed.

Impact of sodium glucose cotransporter 2 (SGLT2) inhibitors on atherosclerosis: from pharmacology to pre-clinical and clinical therapeutics

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are new oral drugs for the therapy of patients with type 2 diabetes mellitus (T2DM). Research in the past decade has shown that drugs of the SGLT2i class, such as empagliflozin, canagliflozin, and dapagliflozin, have pleiotropic effects in preventing cardiovascular diseases beyond their favorable impact on hyperglycemia. Of clinical relevance, recent landmark cardiovascular outcome trials have demonstrated that SGLT2i reduce major adverse cardiovascular events, hospitalization for heart failure, and cardiovascular death in T2DM patients with/without cardiovascular diseases (including atherosclerotic cardiovascular diseases and various types of heart failure). The major pharmacological action of SGLT2i is through inhibiting glucose re-absorption in the kidney and thus promoting glucose excretion. Studies in experimental models of atherosclerosis have shown that SGLT2i ameliorate the progression of atherosclerosis by mechanisms including inhibition of vascular inflammation, reduction in oxidative stress, reversing endothelial dysfunction, reducing foam cell formation and preventing platelet activation. Here, we summarize the anti-atherosclerotic actions and mechanisms of action of SGLT2i, with an aim to emphasize the clinical utility of this class of agents in preventing the insidious cardiovascular complications accompanying diabetes.

Cardiovascular and renal outcomes with canagliflozin according to baseline diuretic use: a post hoc analysis from the CANVAS Program

Aims

The CANVAS Program identified the effect of canagliflozin on major adverse cardiovascular events (MACE) differed according to whether participants were using diuretics at study commencement. We sought to further evaluate this finding related to baseline differences, treatment effects, safety, and risk factor changes.

Methods and results

The CANVAS Program enrolled 10 142 participants with type 2 diabetes mellitus and high cardiovascular risk. Participants were randomized to canagliflozin or placebo and followed for a mean of 188 weeks. The primary outcome was major cardiovascular events, a composite of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. Secondary outcomes included multiple cardiovascular, renal, and safety events. In this post hoc subgroup analysis, participants were categorized according to baseline use of any diuretic. The effect on outcomes was compared using Cox proportional hazards models, while risk factor changes were compared using mixed‐effect models. At baseline, 4490 (44.3%) participants were using a diuretic. Compared with those not using a diuretic, participants using a diuretic were more likely to be older (mean age ± standard deviation, 64.3 ± 8.0 vs. 62.5 ± 8.3), be female (38.9% vs. 33.4%), and have heart failure (19.6% vs. 10.3%) (all P_difference < 0.0001). The effect of canagliflozin on major cardiovascular events was greater for those using diuretic at baseline than for those who were not [adjusted hazard ratio 0.65 (95% confidence interval 0.54–0.78) vs. adjusted hazard ratio 1.13 (95% confidence interval 0.93–1.36), P_{heterogeneity} < 0.0001]. Changes in most risk factors, including blood pressure, body weight, and urine albumin‐to‐creatinine ratio, were similar between groups (all P_difference > 0.11), although the effect of canagliflozin on haemoglobin A1c reduction was slightly weaker in participants using compared with not using diuretics at baseline (−0.52% vs. −0.64%, P_{heterogeneity} = 0.0007). Overall serious adverse events and key safety outcomes, including adverse renal events, were also similar (all P_{heterogeneity} > 0.07).

Conclusions

Participants on baseline diuretics derived a greater benefit for major cardiovascular events from canagliflozin, which was not fully explained by differences in participant characteristics nor risk factor changes.

Mechanisms and Perspectives of Sodium-Glucose Co-transporter 2 Inhibitors in Heart Failure

Heart failure (HF) is a common complication or late-stage manifestation of various heart diseases. Numerous risk factors and underlying causes may contribute to the occurrence and progression of HF. The pathophysiological mechanisms of HF are very complicated. Despite accumulating advances in treatment for HF during recent decades, it remains an intractable clinical syndrome with poor outcomes, significantly reducing the quality of life and expectancy of patients, and imposing a heavy economic burden on society and families. Although initially classified as antidiabetic agents, sodium-glucose co-transporter 2 (SGLT2) inhibitors have demonstrated reduced the prevalence of hospitalization for HF, cardiovascular death, and all-cause death in several large-scale randomized controlled clinical trials. These beneficial effects of SGLT-2 inhibitors can be attributed to multiple hemodynamic, inflammatory and metabolic mechanisms, not only reducing the serum glucose level. SGLT2 inhibitors have been used increasingly in treatment for patients with HF with reduced ejection fraction due to their surprising performance in improving the prognosis. In addition, their roles and mechanisms in patients with HF with preserved ejection fraction or acute HF have also attracted attention. In this review article, we discuss the possible mechanisms and applications of SGLT2 inhibitors in HF.

Natriuretic Effect of Two Weeks of Dapagliflozin Treatment in Patients With Type 2 Diabetes and Preserved Kidney Function During Standardized Sodium Intake: Results of the DAPASALT Trial

OBJECTIVE

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk for heart failure hospitalization potentially by inducing sodium excretion, osmotic diuresis, and plasma volume contraction. Few studies have investigated this hypothesis, but none have assessed cumulative sodium excretion with SGLT2 inhibition during standardized sodium intake in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

The DAPASALT trial was a mechanistic, nonrandomized, open-label study in patients with type 2 diabetes with preserved kidney function on a controlled standardized sodium diet (150 mmol/day). It evaluated the effects of dapagliflozin on sodium excretion, 24-h blood pressure, and extracellular, intracellular, and plasma volumes at the start of treatment (ST) (days 2-4), end of treatment (ET) (days 12-14), and follow-up (FU) (days 15-18).

RESULTS

Fourteen patients were included in the efficacy analysis. Mean (SD) baseline sodium excretion (150 [32] mmol/24-h) did not significantly change during treatment (change at ST: -7.0 mmol/24-h [95% CI -22.4, 8.4]; change at ET: 2.1 mmol/24-h [-28.8, 33.0]). Mean baseline 24-h systolic blood pressure was 128 (10) mmHg and significantly reduced at ST (-6.1 mmHg [-9.1, -3.1]; P < 0.001) and ET (-7.2 mmHg [-10.0, -4.3]; P < 0.001). Dapagliflozin did not significantly alter plasma volume or intracellular volume, while extracellular volume changed at ST (-0.7 L [-1.3, -0.1]; P = 0.02). As expected, 24-h urinary glucose excretion significantly increased during dapagliflozin treatment and reversed during FU.

CONCLUSIONS

During standardized sodium intake, dapagliflozin reduced blood pressure without clear changes in urinary sodium excretion, suggesting that factors other than natriuresis and volume changes may contribute to the blood pressure-lowering effects.

Does SGLT2 Inhibition Affect Sympathetic Nerve Activity in Type 2 Diabetes?

SGLT2 inhibitors increase renal glucose excretion and thus decrease both fasting and postprandial plasma glucose levels. The effects of SGLT2 inhibition outweigh those on glycemic control and are also associated with the induction of hemodynamic changes that improve cardiovascular and renal function in people with type 2 diabetes. The exact mechanisms have not yet been completely clarified. This review is focused on the potential relationship between SGLT2 inhibition and sympathetic nerve activity. There is accumulating evidence for a suppressive effect of SGLT2 inhibitors on the sympathetic nerve tone, which might be a putative mechanism for cardiovascular protection in subjects with type 2 diabetes.

Endothelial response to glucose: dysfunction, metabolism, and transport

The endothelial cell response to glucose plays an important role in both health and disease. Endothelial glucose-induced dysfunction was first studied in diabetic animal models and in cells cultured in hyperglycemia. Four classical dysfunction pathways were identified, which were later shown to result from the common mechanism of mitochondrial superoxide overproduction. More recently, non-coding RNA, extracellular vesicles, and sodium-glucose cotransporter-2 inhibitors were shown to affect glucose-induced endothelial dysfunction. Endothelial cells also metabolize glucose for their own energetic needs. Research over the past decade highlighted how manipulation of endothelial glycolysis can be used to control angiogenesis and microvascular permeability in diseases such as cancer. Finally, endothelial cells transport glucose to the cells of the blood vessel wall and to the parenchymal tissue. Increasing evidence from the blood-brain barrier and peripheral vasculature suggests that endothelial cells regulate glucose transport through glucose transporters that move glucose from the apical to the basolateral side of the cell. Future studies of endothelial glucose response should begin to integrate dysfunction, metabolism and transport into experimental and computational approaches that also consider endothelial heterogeneity, metabolic diversity, and parenchymal tissue interactions.

Sodium Glucose Cotransporter 2 Inhibitors Reduce the Risk of Heart Failure Hospitalization in Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Aim

To evaluate the impact of sodium glucose cotransporter 2 inhibitors (SGLT-2i) on risk of heart failure hospitalization in patients with type 2 diabetes.

Methods

We searched the PubMed, Embase, The Cochrane Library, CNKI, Wanfang, CBM, and other web knowledge databases for data from randomized controlled trials. We performed statistical analyses by using review Manager (RevMan) 5.3 and STATA 12.0 for meta-analysis.

Results

Eight randomized controlled trials that compared SGLT-2i versus placebo met our inclusion criteria and were included in the study. The final meta-analysis included a total of 55,763 type 2 diabetes patients. Compared with placebo, SGLT-2i reduced the risk of heart failure hospitalization (RR, 0.63; 95% CI, 0.53 to 0.74; P < 0.00001), MACE (defined as cardiovascular death, myocardial infarction, or ischemic stroke) (RR, 0.92; 95% CI, 0.86 to 0.98; P < 0.007), cardiovascular death (RR, 0.78; 95%CI, 0.62 to 0.99; P = 0.04) in type 2 diabetes patients. SGLT-2i could reduce the risk of death from any cause (RR, 0.77; 95% CI, 0.59 to 1.01; P = 0.06) without statistical significance in type 2 diabetes patients.

Conclusion

Compared with placebo, SGLT-2i may reduce the risk of heart failure hospitalization, MACE, and cardiovascular death. Therefore, SGLT-2i may be an ideal choice for type 2 diabetes mellitus patient with heart failure. These results will help inform practitioners, patients, and authorities making appropriate choices in hypoglycemic therapy clinical practice.

Relationship between basal sodium intake and the effects of dapagliflozin in albuminuric diabetic kidney disease

We investigated the impact of basal dietary sodium intake on the dapagliflozin-induced changes in albuminuria and blood pressure (BP) measured at home in patients with diabetic kidney disease (DKD).This was a secondary analysis of the Y-AIDA Study, in which DKD patients with estimated glomerular filtration rate (eGFR) ≥ 45 ml/min/1.73 m² and urinary albumin-to-creatinine ratio (UACR) ≥ 30 mg/g creatinine were administered dapagliflozin for 24 weeks, and dapagliflozin significantly improved albuminuria levels and home BP profiles. The effects on UACR, home-measured BP, and eGFR were compared between high- and low-sodium intake groups (HS and LS groups), which were created using baseline urinary sodium-to-creatinine ratio of 84 participants with available basal sodium-to-creatinine ratios. At baseline, clinic-/home-measured BPs, UACR, and eGFR, were comparable in the two groups. After 24 weeks, the reductions from baseline in ln-UACR were comparable in the two groups. In contrast, the reductions in evening home systolic BP and eGFR from baseline were larger in HS than in LS (BP: − 13 ± 2.08 vs. − 6 ± 1.88, P = 0.020; eGFR: − 3.33 ± 1.32 vs. 0.37 ± 1.29, P = 0.049). The home BP-lowering effects of dapagliflozin are larger in HS than LS, concomitant with a larger reduction in eGFR, suggesting a dapagliflozin-induced improvement in glomerular relative hyperfiltration in HS.

Effects of dapagliflozin on blood pressure variability in patients with prediabetes and prehypertension without pharmacological treatment: a randomized trial

AIM

The aim of the study was to evaluate the effect of dapagliflozin on blood pressure variability (BPV) in patients with prediabetes and prehypertension without pharmacological treatment.

METHODS

A double-blind, randomized, placebo-controlled clinical study was performed in 30 patients (30-60 years) diagnosed with prediabetes and prehypertension. Study subjects were divided into two groups: a 10-mg dose of dapagliflozin was administered daily before breakfast for 12 weeks in 15 patients or placebo in the remaining 15 patients. At the beginning and end of the study, clinical and metabolic evaluations were performed, and the 24-h BPV was calculated.

RESULTS

Dapagliflozin significantly decreased body weight (P = 0.010), BMI (P = 0.011), fasting plasma glucose (P = 0.002), glycated hemoglobin A1c (P = 0.004), office systolic blood pressure (SBP) (P = 0.001), office diastolic blood pressure (DBP) (P = 0.011), 24-h SBP (121 ± 8 vs. 117 ± 11 mmHg, P = 0.046), nighttime SBP (114 ± 11 vs. 108 ± 10 mmHg, P = 0.017), nocturnal mean arterial pressure (P = 0.043), and nocturnal hypertensive load (P = 0.015); and it significantly increased the percentage of the dipper circadian BP pattern (16.7 vs. 30.8%, P = 0.047). After the administration of dapagliflozin, some of the patients did not meet the diagnostic criteria for prediabetes (26.9%) or prehypertension (26.9%).

CONCLUSIONS

The administration of 10 mg dapagliflozin once daily for 90 days in patients with prediabetes and prehypertension decreased BPV by reducing 24-h and nighttime SBP, and increasing the dipper circadian BP pattern.

Effect of tofogliflozin on arterial stiffness in patients with type 2 diabetes: prespecified sub-analysis of the prospective, randomized, open-label, parallel-group comparative UTOPIA trial

BACKGROUND

Tofogliflozin, an SGLT2 inhibitor, is associated with favorable metabolic effects, including improved glycemic control and serum lipid profile and decreased body weight, visceral adipose tissue, and blood pressure (BP). This study evaluated the effects of tofogliflozin on the brachial-ankle pulse wave velocity (baPWV) in patients with type 2 diabetes (T2DM) without a history of apparent cardiovascular disease.

METHODS

The using tofogliflozin for possible better intervention against atherosclerosis for type 2 diabetes patients (UTOPIA) trial is a prospective, randomized, open-label, multicenter, parallel-group, comparative study. As one of the prespecified secondary outcomes, changes in baPWV over 104 weeks were evaluated in 154 individuals (80 in the tofogliflozin group and 74 in the conventional treatment group) who completed baPWV measurement at baseline.

RESULTS

In a mixed-effects model, the progression in the right, left, and mean baPWV over 104 weeks was significantly attenuated with tofogliflozin compared to that with conventional treatment (- 109.3 [- 184.3, - 34.3] (mean change [95% CI] cm/s, p = 0.005; - 98.3 [- 172.6, - 24.1] cm/s, p = 0.010; - 104.7 [- 177.0, - 32.4] cm/s, p = 0.005, respectively). Similar findings were obtained even after adjusting the mixed-effects models for traditional cardiovascular risk factors, including body mass index (BMI), glycated hemoglobin (HbA1c), total cholesterol, high-density lipoprotein (HDL)-cholesterol, triglyceride, systolic blood pressure (SBP), hypertension, smoking, and/or administration of drugs, including hypoglycemic agents, antihypertensive agents, statins, and anti-platelets, at baseline. The findings of the analysis of covariance (ANCOVA) models, which included the treatment group, baseline baPWV, and traditional cardiovascular risk factors, resembled those generated by the mixed-effects models.

CONCLUSIONS

Tofogliflozin significantly inhibited the increased baPWV in patients with T2DM without a history of apparent cardiovascular disease, suggesting that tofogliflozin suppressed the progression of arterial stiffness. Trial Registration UMIN000017607. Registered 18 May 2015. ( https://www.umin.ac.jp/icdr/index.html ).

Targeting the Vascular Endothelium in the Treatment of COVID-19

ABSTRACT

The involvement of the vascular endothelium in the complications of coronavirus disease 2019 is now recognized. Chief among these are pulmonary endotheliitis, cytokine storm, endotoxic shock, and cardiovascular collapse. This Perspectives article is focused on therapeutical strategies to reduce the risk of these complications by targeting the vascular endothelium as a part of the overall treatment of coronavirus disease 2019.

Dapagliflozin improves cardiovascular risk factors in Emirati patients with T2DM

BACKGROUND

Dapagliflozin is a sodium-glucose co transporter-2 inhibitor that proved efficacy in reduction of blood glucose level through extrusion of glucose in urine. It is used in treatment of type 2 diabetes mellitus (T2DM). It also has reported cardiovascular and renal benefits in patients with T2DM. Data are very limited about its effects in Emirati patients with diabetes. Our aim was to evaluate dapagliflozin treatment in Emirati patients with T2DM.

PATIENTS AND METHODS

This is a retrospective study involving 89 diabetes patients who were using dapagliflozin 10 mg once daily as add-on therapy for 12 months. All patients had T2DM, aged over 18 years and had an estimated glomerular filtration rate (eGFR) over 60 ml/min/1.73 m². Body weight, height, body mass index, sitting blood pressure and heart rate were collected. Fasting plasma glucose, glycosylated hemoglobin (HbA1c), lipid profile and other available biochemical parameters, for example, creatinine, blood urea nitrogen, and urine albumin/creatinine ratio were traced from medical records and eGFR was calculated.

RESULTS

Patients were aged 62.3 ± 9.4 years with a median duration of diabetes of 15 (10-20) years. Data were analyzed before, at 6 months and 12 months of treatment. Fasting plasma glucose, HbA1c, body mass index, systolic and diastolic blood pressure significantly decreased (p = 0.002, p < 0.0005, p < 0.002, p < 0.0005, p < 0.0005, respectively). The median reduction of HbA1c was 0.7% (0.2-1.2) and 0.9% (0.5-1.8) at 6 and 12 months, respectively. Systolic blood pressure decreased by a median of 7 mmHg (4-20 mmHg) and 9 mmHg (1-10 mmHg) on the 6th and 12th month of treatment, respectively, while the diastolic decreased by a median of 3 mmHg (4 to 10 mmHg) and 6 mmHg (1-10 mmHg); without increase in heart rate (p = 0.188). A significant reduction of body mass index, C-reactive protein and rate pressure product was noticed (p = 0.002, p = 0.001, p < 0.0005, respectively). No decline in eGFR or microalbuminuria was noticed. Stage I chronic kidney disease with eGFR < 90 ml/min/1.73 m² showed continuous progressive reduction of HbA1c without a significant change in other variables.

CONCLUSION

Our data indicate improved cardiovascular risk profile in dapagliflozin-treated Emirati patients with T2DM.

Nephroprotection by SGLT2i in CKD Patients: May It Be Modulated by Low-Protein Plant-Based Diets?

Sodium-glucose-transporter 2 inhibitors (SGLT2i) are a new class of anti-diabetic drugs that in large trials such as CREDENCE have shown also a reduction of glomerular hyperfiltration and albuminuria in type 2 diabetic patients. Hence, the interest toward SGLT2i is focused toward this potential nephroprotective effect, in order to reduce the progression to overt nephropathy, and it seems to be confirmed in the most recent DAPA-CKD trial. This is the reason why the indication for SGLT2i treatment has been extended to chronic kidney disease (CKD) patients with eGFR up to 30 ml/min, namely with CKD stage 1-3. In patients with CKD stage 3 to 5, the most recent KDIGO guidelines recommend low-protein diet and plant-based regimens to delay end-stage kidney disease (ESKD) and improve quality of life. Similarly to SGLT2i, low-protein diets exert renal-protective effects by reducing single nephron hyperfiltration and urinary protein excretion. Beyond the glomerular hemodynamic effects, both protein restriction and SGLT2i are able to restore autophagy and, through these mechanisms, they may exert protective effects on diabetic kidney disease. In this perspective, it is likely that diet may modulate the effect of SGLT2i in CKD patients. Unfortunately, no data are available on the outcomes of the association of SGLT2i and low-protein and/or vegan diets. It is therefore reasonable to investigate whether CKD patients receiving SGLT2i may have further advantages in terms of nephroprotection from the implementation of a low-protein and/or plant-based diet or whether this association does not result in an additive effect, especially in vascular nephropathies.

Carotid Doppler ultrasonographic findings of dapagliflozin use in type 2 diabetic patients

AIM

Sodium-glucose cotransporter 2 inhibitors have been shown to reduce the risk of cardiovascular disease in type 2 diabetes (T2DM) patients. The purpose of this study was to evaluate cardiovascular disease risk indirectly through Doppler ultrasonography (USG) of carotid artery vascular markers in T2DM patients using dapagliflozin.

METHODS

One hundred forty-five patients presenting to our clinic between March 2016 and June 2018 and diagnosed with T2DM were included in the study. These were divided into two groups - a dapagliflozin group of 85 patients and a 60-member non-dapagliflozin control group. Common carotid artery end-diastolic velocity (EDV), peak systolic velocity (PSV), and resistive index (RI) parameters were evaluated using Doppler USG in both groups.

RESULTS

The mean duration of follow-up was 2.2 ± 0.4 years. Mean ages were 45 ± 14 years in the dapagliflozin group and 42 ± 15 in the control group. Mean HbA1c was 7.4 ± 1.6 in the dapagliflozin group and 7.3 ± 2.1 in the control group. Common carotid artery, PSV, and EDV parameters were higher (p = .012/p = .036), while RI was lower (p ˂ .001), in the dapagliflozin group than in the control group.

CONCLUSION

Vascular resistance was lower in the group using dapagliflozin for diabetes management.