Rationale and design of a multicenter placebo-controlled double-blind randomized trial to evaluate the effect of empagliflozin on endothelial function: the EMBLEM trial

Blood pressure reduction with empagliflozin in Japanese patients with type 2 diabetes and cardiovascular diseases: a post-hoc sub-analysis of the placebo-controlled randomized EMBLEM trial

Detailed effect of sodium-glucose cotransporter 2 inhibitors on blood pressure (BP) in Japanese patients with type 2 diabetes (T2D) at a high risk of cardiovascular disease (CVD) is not fully understood. In this post-hoc sub-analysis of placebo-controlled randomized EMBLEM trial for Japanese patients with T2D and CVD, 105 participants (empagliflozin N = 52, placebo N = 53) were included, and office systolic/diastolic BPs and mean arterial pressure (MAP) over 24 weeks were estimated using mixed-effects models for repeated measures. Empagliflozin therapy, compared to placebo, reduced systolic/diastolic BPs (mean group difference in change from baseline to week 24; -5.9 [95% confidence interval (CI), -10.4 to -1.4] mmHg/-2.9 [95% CI, -6.2 to 0.4] mmHg) and MAP ( - 3.8 [95% CI, -7.0 to -0.7] mmHg). The systolic BP reduction was almost consistent across differing background clinical characteristics and usage status of anti-hypertensive medications.

Ischemia and no obstructive coronary arteries (INOCA): A narrative review

Myocardial ischemia with no obstructive coronary arteries (INOCA) is a chronic coronary syndrome condition that is increasingly being recognized as a substantial contributor to adverse cardiovascular mortality and outcomes, including myocardial infarction and heart failure with preserved ejection fraction (HFpEF). While INOCA occurs in both women and men, women are more likely to have the finding of INOCA and are more adversely impacted by angina, with recurrent hospitalizations and a lower quality of life with this condition. Abnormal epicardial coronary vascular function and coronary microvascular dysfunction (CMD) have been identified in a majority of INOCA patients on invasive coronary function testing. CMD can co-exist with obstructive epicardial coronary artery disease (CAD), diffuse non-obstructive epicardial CAD, and with coronary vasospasm. Epicardial vasospasm can also occur with normal coronary arteries that have no atherosclerotic plaque on intravascular imaging. While all predisposing factors are not clearly understood, cardiometabolic risk factors, and endothelium dependent and independent mechanisms that increase oxidative stress and inflammation are associated with microvascular injury, CMD and INOCA. Cardiac autonomic dysfunction has also been implicated in abnormal vasoreactivity and persistent symptoms. INOCA is under-recognized and under-diagnosed, partly due to the heterogenous patient populations and mechanisms. However, diagnostic testing methods are available to guide INOCA management. Treatment of INOCA is evolving, and focuses on cardiac risk factor control, improving ischemia, reducing atherosclerosis progression, and improving angina and quality of life. This review focuses on INOCA, relations to HFpEF, available diagnostics, current and investigational therapeutic strategies, and knowledge gaps in this condition.

Empagliflozin for Patients with Heart Failure and Type 2 Diabetes Mellitus: Clinical Evidence in Comparison with Other Sodium-Glucose Co-transporter-2 Inhibitors and Potential Mechanism

Heart failure remains a leading cause of morbidity and mortality globally and has been recognized as a common complication of diabetes, especially type 2 diabetes mellitus. Heart failure occurs in diabetic patients even in the absence of hypertension, coronary heart disease, or valvular heart disease, and is, therefore, a major cardiovascular complication in this vulnerable population. Given the continued rise in the prevalence of type 2 diabetes mellitus worldwide, the burden of heart failure on the healthcare system will continue to increase. Recent evidence demonstrates that empagliflozin, a sodium-glucose co-transporter-2 inhibitor, brings clinical benefit to patients with established heart failure and type 2 diabetes mellitus. Herein, we critically reviewed the clinical evidence of empagliflozin for patients with heart failure and type 2 diabetes mellitus with the comparison with other sodium-glucose co-transporter-2 inhibitors and potential mechanism to provide the optimal and evidence-based management for patients with established heart failure and type 2 diabetes mellitus with the goal to be conducive to the mechanism exploration of empagliflozin to advance a more comprehensive understanding of empagliflozin.

Chemical characterization and DPP-IV inhibitory activity evaluation of tripeptides from Gynura divaricata (L.) DC

ETHNOPHARMACOLOGICAL RELEVANCE

Gynura divaricata (L.) DC. (GD), a herbal medicine, has been used for the prevention and treatment of hyperglycemia in China. However, hypoglycemic ingredients within GD have not yet been well studied.

AIM OF THE STUDY

The aim of this study was to explore undiscovered compounds with dipeptidyl peptidase IV (DPP-IV) inhibitory activity within GD.

MATERIALS AND METHODS

A four-step strategy was developed to explore undiscovered DPP-IV inhibitors within GD. First, the components were preliminarily characterized using UHPLC-HRMS combined with a library search. Second, preliminarily characterized compounds were searched for potential bioactivity. Third, a mixture of these preliminarily characterized compounds was isolated and thoroughly characterized based on fragmentation patterns associated with molecular networking. Fourth, the activities of these compounds were verified using DPP-IV inhibitory assay and molecular docking.

RESULTS

Diprotin A, a tripeptide inhibitor against DPP-IV, was identified. Thereafter, a mixture of twenty-five diprotin A analogs was isolated and characterized, which exhibited IC₅₀ of 0.40 mg/mL for DPP-IV. Molecular docking results also confirmed the interactions between the tripeptide analogs and DPP-IV mainly via H-bonds and hydrophobic interactions.

CONCLUSIONS

This is the first report of DPP-IV inhibitors within GD. These findings demonstrate that the extract of GD might be beneficial for the treatment of type 2 diabetes mellitus, and is expected to promote further development and utilization of GD in herbal medicine.

Effect of Topiroxostat on Brain Natriuretic Peptide Level in Patients with Heart Failure with Preserved Ejection Fraction: A Pilot Study

BACKGROUND

Various optimal medical therapies have been established to treat heart failure (HF) with reduced ejection fraction (HFrEF). Both HFrEF and HF with preserved ejection fraction (HFpEF) are associated with poor outcomes. We investigated the effect of topiroxostat, an oral xanthine oxidoreductase inhibitor, for HFpEF patients with hyperuricemia or gout.

METHODS

In this nonrandomized, open-label, single-arm trial, we administered topiroxostat 40-160 mg/day to HFpEF patients with hyperuricemia or gout to achieve a target uric acid level of 6.0 mg/dL. The primary outcome was rate of change in log-transformed brain natriuretic peptide (BNP) level from baseline to 24 weeks after topiroxostat treatment. The secondary outcomes included amount of change in BNP level, uric acid evaluation values, and oxidative stress marker levels after 24 weeks of topiroxostat treatment. Thirty-six patients were enrolled; three were excluded before study initiation.

RESULTS

Change in log-transformed BNP level was -3.4 ± 8.9% (p = 0.043) after 24 weeks of topiroxostat treatment. The rate of change for the decrease in BNP level was -18.0 (-57.7, 4.0 pg/mL; p = 0.041). Levels of uric acid and 8-hydroxy-2'-deoxyguanosine/creatinine, an oxidative stress marker, also significantly decreased (-2.8 ± 1.6 mg/dL, p < 0.001, and -2.3 ± 3.7 ng/mgCr, p = 0.009, respectively).

CONCLUSIONS

BNP level was significantly lower in HFpEF patients with hyperuricemia or gout after topiroxostat administration; however, the rate of decrease was low. Further trials are needed to confirm our findings.

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.

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.

Comparison of the clinical effect of empagliflozin on glycemic and non-glycemic parameters in Japanese patients with type 2 diabetes and cardiovascular disease treated with or without baseline metformin

Background

The most recent treatment guidelines for type 2 diabetes (T2D) recommend sodium-glucose cotransporter 2 (SGLT2) inhibitors should be considered preferentially in patients with T2D with either a high cardiovascular risk or with cardiovascular disease (CVD), regardless of their diabetes status and prior use of conventional metformin therapy. Whether the therapeutic impact of SGLT2 inhibitors on clinical parameters differs according to the use of metformin therapy however remains unclear.

Methods

The study was a post hoc analysis of the EMBLEM trial (UMIN000024502). All participants (n = 105; women 31.4%; mean age 64.8 years) had both T2D and CVD and were randomized to either 24 weeks of empagliflozin 10 mg daily or placebo. Analysis of the data assessed the effect of empagliflozin on changes from baseline to 24 weeks in glycemic and non-glycemic clinical parameters, according to the baseline use of metformin.

Results

Overall, 53 (50.5%) patients received baseline metformin. In the 52 patients treated with empagliflozin (48.1% with baseline metformin), the decrease in systolic blood pressure from baseline levels was greater in patients receiving metformin, compared to that observed in metformin-naïve patients (group difference − 8.5 [95% confidence interval (CI) − 17.7 to 0.6 mmHg], p = 0.066). Reduction in body mass index (BMI) was significantly greater in patients receiving baseline metformin, relative to nonusers (− 0.54 [95% CI − 1.07 to − 0.01] kg/m², p = 0.047). The group ratio (baseline metformin users vs. nonusers) of proportional changes in the geometric mean of high-sensitivity Troponin-I (hs-TnI) was 0.74 (95% CI 0.59 to 0.92, p = 0.009). No obvious differences were observed in glycemic parameters (fasting plasma glucose, glycohemoglobin, and glycoalbumin) between the baseline metformin users and nonusers.

Conclusion

Our findings suggest 24 weeks of empagliflozin treatment was associated with an improvement in glycemic control, irrespective of the baseline use of metformin therapy. The effects of empagliflozin on reductions in BMI and hs-TnI were more apparent in patients who received baseline metformin therapy, compared to that observed in metformin-naïve patients.

Trial registration University Medical Information Network Clinical Trial Registry, number 000024502

Reduction of estimated fluid volumes following initiation of empagliflozin in patients with type 2 diabetes and cardiovascular disease: a secondary analysis of the placebo-controlled, randomized EMBLEM trial

Backgrounds/Aim

Sodium glucose co-transporter 2 inhibitors promote osmotic/natriuretic diuresis and reduce excess fluid volume, and this improves cardiovascular outcomes, including hospitalization for heart failure. We sought to assess the effect of empagliflozin on estimated fluid volumes in patients with type 2 diabetes and cardiovascular disease (CVD).

Methods

The study was a post-hoc analysis of the EMBLEM trial (UMIN000024502), an investigator-initiated, multi-center, placebo-controlled, double-blinded, randomized-controlled trial designed primarily to evaluate the effect of 24 weeks of empagliflozin treatment on vascular endothelial function in patients with type 2 diabetes and established CVD. The analysis compared serial changes between empagliflozin (10 mg once daily, n = 52) and placebo (n = 53) in estimated plasma volume (ePV), calculated by the Straus formula and estimated the extracellular volume (eEV), determined by the body surface area, measured at baseline and 4, 12, and 24 weeks after initiation of treatment. Correlations were examined between the changes from baseline to week 24 in each estimated fluid volume parameter and several clinical variables of interest, including N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration.

Results

In an analysis using mixed-effects models for repeated measures, relative to placebo empagliflozin reduced ePV by − 2.23% (95% CI − 5.72 to 1.25) at week 4, − 8.07% (− 12.76 to − 3.37) at week 12, and − 5.60% (− 9.87 to − 1.32) at week 24; eEV by − 70.3 mL (95% CI − 136.8 to − 3.8) at week 4, − 135.9 mL (− 209.6 to − 62.3) at week 12, and − 144.4 mL (− 226.3 to − 62.4) at week 24. The effect of empagliflozin on these parameters was mostly consistent across various patient clinical characteristics. The change in log-transformed NT-proBNP was positively correlated with change in ePV (r = 0.351, p = 0.015), but not with change in eEV.

Conclusions

Our data demonstrated that initiation of empagliflozin treatment substantially reduced estimated fluid volume parameters in patients with type 2 diabetes and CVD, and that this effect was maintained for 24 weeks. Given the early beneficial effect of empagliflozin on cardiovascular outcomes seen in similar patient populations, our findings provide an important insight into the key mechanisms underlying the clinical benefit of the drug.

Trial registration University Medical Information Network Clinical Trial Registry, number 000024502

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01295-6.

Secondary analyses to assess the profound effects of empagliflozin on endothelial function in patients with type 2 diabetes and established cardiovascular diseases: The placebo-controlled double-blind randomized effect of empagliflozin on endothelial function in cardiovascular high risk diabetes mellitus: Multi-center placebo-controlled double-blind randomized trial

Aims/Introduction

Recent clinical trials on sodium–glucose cotransporter 2 inhibitors showed improved outcomes in patients with type 2 diabetes at a high risk of cardiovascular events. However, the underlying effects on endothelial function remain unclear.

Materials and Methods

The effect of empagliflozin on endothelial function in cardiovascular high risk diabetes mellitus: Multi‐center placebo‐controlled double‐blind randomized (EMBLEM) trial in patients with type 2 diabetes and cardiovascular disease showed empagliflozin treatment for 24 weeks had no effect on peripheral endothelial function measured by reactive hyperemia peripheral arterial tonometry. This post‐hoc analysis of the EMBLEM trial included a detailed evaluation of the effects of empagliflozin on peripheral endothelial function in order to elucidate the clinical characteristics of responders or non‐responders to treatment.

Results

Of the 47 patients randomized into the empagliflozin group, 21 (44.7%) showed an increase in the reactive hyperemia index (RHI) after 24 weeks of intervention, with no apparent difference in the clinical characteristics between patients whose RHI either increased (at least >0) or did not increase. There was also no obvious difference between the treatment groups in the proportion of patients who had a clinically meaningful change (≥15%) in log‐transformed RHI. No correlation was found between changes in RHI and clinical variables, such as vital signs and laboratory parameters.

Conclusions

Treatment with empagliflozin for 24 weeks in patients with type 2 diabetes and cardiovascular disease did not affect peripheral endothelial function, and was not related to changes in clinical variables, including glycemic parameters. These findings suggest that the actions of sodium–glucose cotransporter 2 inhibitors other than direct improvement in peripheral endothelial function were responsible, at least in the early phase, for the clinical benefits found in recent cardiovascular outcome trials.

Rationale and design of an investigator-initiated, multicenter, prospective open-label, randomized trial to evaluate the effect of ipragliflozin on endothelial dysfunction in type 2 diabetes and chronic kidney disease: the PROCEED trial

Background

Type 2 diabetes (T2D) is associated with renal impairment and vascular endothelial dysfunction. Therefore, this pathological connection is an important therapeutic target. Recent cardiovascular and renal outcome trials demonstrated that sodium glucose cotransporter 2 inhibitors (SGLT2is) consistently reduced the risks of cardiovascular and renal events and mortality in patients with T2D and various other background risks including chronic kidney disease (CKD). However, the precise mechanisms by which SGLT2is accords these therapeutic benefits remain uncertain. It is also unknown whether these SGLT2is-associated benefits are associated with the amelioration of endothelial dysfunction in patients with T2D and CKD.

Methods

The PROCEED trial is an investigator-initiated, prospective, multicenter, open-label, randomized-controlled trial. The target sample size is 110 subjects. After they furnish informed consent and their endothelial dysfunction is confirmed from their decreased reactive hyperemia indices (RHI), eligible participants with T2D (HbA1c, 6.0–9.0%) and established CKD (30 mL/min/1.73 m² ≤ estimated glomerular filtration ratio [eGFR] < 60 and/or ≥ urine albumin-to-creatinine ratio 30 mg/g Cr) will be randomized (1:1) to receive either 50 mg ipragliflozin daily or continuation of background treatment (non-SGLT2i). The primary endpoint is the change in RHI from baseline after 24 weeks. To compare the treatment effects between groups, the baseline-adjusted means and their 95% confidence intervals will be estimated by analysis of covariance adjusted for HbA1c (< 7.0% or ≥ 7.0%), age (< 70 y or ≥ 70 y), RHI (< 1.67 or ≥ 1.67), eGFR (< 45 mL/min/1.73 m² or ≥ 45 mL/min/1.73 m²), and smoking status. Prespecified responder analyses will be also conducted to determine the proportions of patients with clinically meaningful changes in RHI at 24 weeks.

Discussion

PROCEED is the first trial to examine the effects of ipragliflozin on endothelial dysfunction in patients with T2D and CKD. This ongoing trial will establish whether endothelial dysfunction is a therapeutic target of SGLT2is in this population. It will also provide deep insights into the potential mechanisms by which SGLT2is reduced the risks of cardiovascular and renal events in recent outcome trials.

Trial registration Unique Trial Number, jRCTs071190054 (https://jrct.niph.go.jp/en-latest-detail/jRCTs071190054).

Endothelium as a Therapeutic Target in Diabetes Mellitus: From Basic Mechanisms to Clinical Practice

Endothelium plays an essential role in human homeostasis by regulating arterial blood pressure, distributing nutrients and hormones as well as providing a smooth surface that modulates coagulation, fibrinolysis and inflammation. Endothelial dysfunction is present in Diabetes Mellitus (DM) and contributes to the development and progression of macrovascular disease, while it is also associated with most of the microvascular complications such as diabetic retinopathy, nephropathy and neuropathy. Hyperglycemia, insulin resistance, hyperinsulinemia and dyslipidemia are the main factors involved in the pathogenesis of endothelial dysfunction. Regarding antidiabetic medication, metformin, gliclazide, pioglitazone, exenatide and dapagliflozin exert a beneficial effect on Endothelial Function (EF); glimepiride and glibenclamide, dipeptidyl peptidase-4 inhibitors and liraglutide have a neutral effect, while studies examining the effect of insulin analogues, empagliflozin and canagliflozin on EF are limited. In terms of lipid-lowering medication, statins improve EF in subjects with DM, while data from short-term trials suggest that fenofibrate improves EF; ezetimibe also improves EF but further studies are required in people with DM. The effect of acetylsalicylic acid on EF is dose-dependent and lower doses improve EF while higher ones do not. Clopidogrel improves EF, but more studies in subjects with DM are required. Furthermore, angiotensin- converting-enzyme inhibitors /angiotensin II receptor blockers improve EF. Phosphodiesterase type 5 inhibitors improve EF locally in the corpus cavernosum. Finally, cilostazol exerts favorable effect on EF, nevertheless, more data in people with DM are required.

Type 2 diabetes mellitus and cardiovascular disease: focus on the effect of antihyperglycemic treatments on cardiovascular outcomes

Introduction: Type 2 diabetes mellitus and cardiovascular disease contribute to significant morbidity, mortality, and health-care resource expenditure. The pathophysiological and clinical associations between diabetes and cardiovascular disease have been the subject of multiple studies, most recently culminating in large trials of several new antiglycemic agents being found to confer additional cardiovascular risk reduction. Understanding the potential cardiovascular benefits of antiglycemic medications offers the unique opportunity to reduce the morbidity and mortality presented by both diseases at once.Areas covered: The literature search was comprised of a Pubmed search querying 'cardiovascular outcomes' and 'diabetes'. This article reviews the pathophysiology of cardiovascular complications in type 2 diabetes and the cardiovascular outcome trials related to newer antiglycemic medications.Expert opinion: The treatment of patients with type 2 diabetes mellitus and cardiovascular disease is rapidly advancing. In particular, the sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists have demonstrated cardiovascular benefit by reducing major adverse cardiovascular events and cardiovascular mortality. Future directions of the treatment of type 2 diabetes and cardiovascular disease will focus on targeting and preventing diabetic cardiomyopathy and further defining the role of SGLT2 inhibitors and of GLP-1 receptor agonists in additional patient populations.

SGLT2 Inhibitors: A Review of Their Antidiabetic and Cardioprotective Effects

Type 2 diabetes mellitus is a chronic metabolic disease associated with high cardiovascular (CV) risk. Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are the latest class of antidiabetic medication that inhibit the absorption of glucose from the proximal tubule of the kidney and hence cause glycosuria. Four SGLT2i are currently commercially available in many countries: canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin. SGLT2i reduce glycated hemoglobin by 0.5%-1.0% and have shown favorable effects on body weight, blood pressure, lipid profile, arterial stiffness and endothelial function. More importantly, SGLT2i have demonstrated impressive cardioprotective and renoprotective effects. The main mechanisms underlying their cardioprotective effects have been attributed to improvement in cardiac cell metabolism, improvement in ventricular loading conditions, inhibition of the Na+/H+ exchange in the myocardial cells, alteration in adipokines and cytokines production, as well as reduction of cardiac cells necrosis and cardiac fibrosis. The main adverse events of SGLT2i include urinary tract and genital infections, as well as euglycemic diabetic ketoacidosis. Concerns have also been raised about the association of SGLT2i with lower limb amputations, Fournier gangrene, risk of bone fractures, female breast cancer, male bladder cancer, orthostatic hypotension, and acute kidney injury.

Sodium-Glucose Cotransporter 2 Inhibitor Protection Against Adverse Cardiovascular and Renal Outcomes in Patients With Type 2 Diabetes

IN BRIEF New treatments for type 2 diabetes are required to demonstrate cardiovascular safety in dedicated cardiovascular outcomes trials (CVOTs). This article reviews available evidence on cardiovascular, renal, and safety outcomes from CVOTs and real-world analyses of sodium-glucose cotransporter 2 inhibitors, along with considerations for their use in clinical practice.

Sodium-Glucose Cotransporter 2 Inhibitors: A Case Study in Translational Research

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are the most recently approved class of diabetes drugs. Unlike other agents, SGLT2 inhibitors act on the kidney to promote urinary glucose excretion. SGLT2 inhibitors provide multiple benefits, including decreased HbA_1c, body weight, and blood pressure. These drugs have received special attention because they decrease the risk of major adverse cardiovascular events and slow progression of diabetic kidney disease (1-3). Balanced against these impressive benefits, the U.S. Food and Drug Administration-approved prescribing information describes a long list of side effects: genitourinary infections, ketoacidosis, bone fractures, amputations, acute kidney injury, perineal necrotizing fasciitis, and hyperkalemia. This review provides a physiological perspective to understanding the multiple actions of these drugs complemented by a clinical perspective toward balancing benefits and risks.

Sotagliflozin, the first dual SGLT inhibitor: current outlook and perspectives

Sotagliflozin is a dual sodium-glucose co-transporter-2 and 1 (SGLT2/1) inhibitor for the treatment of both type 1 (T1D) and type 2 diabetes (T2D). Sotagliflozin inhibits renal sodium-glucose co-transporter 2 (determining significant excretion of glucose in the urine, in the same way as other, already available SGLT-2 selective inhibitors) and intestinal SGLT-1, delaying glucose absorption and therefore reducing post prandial glucose. Well-designed clinical trials, have shown that sotagliflozin (as monotherapy or add-on therapy to other anti-hyperglycemic agents) improves glycated hemoglobin in adults with T2D, with beneficial effects on bodyweight and blood pressure. Similar results have been obtained in adults with T1D treated with either continuous subcutaneous insulin infusion or multiple daily insulin injections, even after insulin optimization. A still ongoing phase 3 study is currently evaluating the effect of sotagliflozin on cardiovascular outcomes (ClinicalTrials.gov NCT03315143). In this review we illustrate the advantages and disadvantages of dual SGLT 2/1 inhibition, in order to better characterize and investigate its mechanisms of action and potentialities.

A sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin comparison with insulin shows important effects on Zn2+-transporters in cardiomyocytes from insulin-resistant metabolic syndrome rats through inhibition of oxidative stress 1

Sodium-glucose cotransporter 2 (SGLT2) inhibitors showed significant effects in patients with diabetes or metabolic syndrome (MetS) with high cardiovascular risk. Although the increased intracellular Zn²⁺ level ([Zn²⁺]_i), oxidative stress, and altered cardiac matrix metalloproteinases (MMPs) in diabetic cardiomyopathy can intersect with different signaling pathways, the exact mechanisms are not known yet. Since either MMPs or SGLT2 have important roles in cardiac-fibrosis under hyperglycemia, we aimed to examine the role of SGLT2 inhibitor dapagliflozin (DAP) on cardiac Zn²⁺-transporters responsible for [Zn²⁺]_i-regulation, comparison to insulin (INS), together with MMP levels and systemic oxidative stress status in MetS-rats. High-carbohydrated diet-induced MetS-rats received DAP or INS for 2 weeks. DAP but not INS in MetS-rats significantly decreased high blood-glucose levels, while both treatments exerted benefits on increased total oxidative status and decreased total antioxidant status in MetS-rat plasma as well as in heart tissue. Protein levels of Zn²⁺-transporters, responsible for Zn²⁺-influx into cytosol, ZIP7 and ZIP14 were increased with significant decrease in ZIP8 of MetS-rat cardiomyoctes, while Zn²⁺-transporters, responsible for cytosolic Zn²⁺-efflux, ZnT7 was decreased with no change in ZnT8. Both treatments induced significant beneficial effects on altered ZIP14, ZIP8, and ZnT7 levels. Furthermore, both treatments exerted benefits on depressed gelatin-zymography and protein expression levels of MMP-2 and MMP-9 in MetS-rat ventricular cardiomyocytes. The direct effect of DAP on heart was also confirmed with measurements of left ventricular developed pressure. Overall, we showed that DAP has important antioxidant-like cardio-protective effects in MetS-rats, similar to INS-effect, affecting Zn²⁺-regulation via Zn²⁺-transporters, MMPs, and oxidative stress. Therefore one can suggest that SGLT2 inhibitors can be new therapeutic agents for cardio-protection not only in hyperglycemia but also in failing heart.

Sodium-Glucose Cotransporter-2 Inhibition in Type 2 Diabetes Mellitus: A Review of Large-Scale Cardiovascular Outcome Studies and Possible Mechanisms of Benefit

Cardiovascular (CV) disease remains the leading cause of morbidity and mortality in individuals with type 2 diabetes mellitus (T2DM). However, conventional antihyperglycemic medications seem to have minimal effect on lowering CV risk despite achieving excellent reductions in glycated hemoglobin A1c and associated reductions in microvascular risk. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have emerged as noteworthy antihyperglycemic agents with concomitant CV and renal protection in T2DM patients. In this comprehensive review, we present the key CV findings from major large-scale outcome trials of SGLT2 inhibitors to date. We also review the mechanistic studies that might explain the CV benefits of SGLT2 inhibition in patients with T2DM.

Effects of SGLT2 inhibitors on systemic and tissue low-grade inflammation: The potential contribution to diabetes complications and cardiovascular disease

Chronic low-grade inflammation is a recognized key feature associated with type 2 diabetes mellitus (T2DM) and its complications. In prospective randomized trials, sodium-glucose cotransporter type 2 (SGLT2) inhibitors have demonstrated benefits related to several cardiovascular and renal risk factors, including HbA_1c, blood pressure, body weight, renal hyperfiltration, and improvement of cardiorenal outcomes. SGLT2 inhibitors may improve adipose tissue function and induce decreases in serum leptin, TNF-α and IL-6 while increasing adiponectin. While data on high-sensitivity C-reactive protein and other inflammatory markers are relatively scarce in humans, in animals, a number of reports have shown reductions in cytokine and chemokine concentrations in parallel with protective effects against progression of atherosclerotic lesions. Experimental findings also suggest that part of the renoprotective effects of SGLT2 inhibition may be related to anti-inflammatory actions at the kidney level. Underlying mechanisms to explain this anti-inflammatory effect are multiple, but may involve weight loss, and reduction in adipose tissue inflammation, slight increase in ketone bodies and diminution of uric acid levels or attenuation of oxidative stress. However, further studies in diabetes patients with specific assessment of inflammatory markers are still necessary to determine the specific contribution of the anti-inflammatory action of SGLT2 inhibitors to the reduction of cardiovascular and renal complications and mortality observed with this class of antidiabetic drugs.

The SGLT2 Inhibitor Dapagliflozin Significantly Improves the Peripheral Microvascular Endothelial Function in Patients with Uncontrolled Type 2 Diabetes Mellitus

Objective Sodium-glucose co-transporter 2 (SGLT2) inhibitors reduce cardiovascular events and decrease the body fat mass in patients with type 2 diabetes mellitus (T2DM). We examined whether or not the SGLT2-inhibitor dapagliflozin can improve the endothelial function associated with a reduction in abdominal fat mass. Methods We prospectively recruited patients with uncontrolled [hemoglobin A1c (HbA1c) >7.0%] T2DM who were not being treated by SGLT2 inhibitors. Patients were treated with add-on dapagliflozin (5 mg/day) or non-SGLT2 inhibitor medicines for 6 months to improve their HbA1c. We measured the peripheral microvascular endothelial function as assessed by reactive hyperemia peripheral arterial tonometry (RH-PAT) and calculated the natural logarithmic transformed value of the RH-PAT index (LnRHI). We then investigated changes in the LnRHI and abdominal fat area using computed tomography (CT). Results The subjects were 54 patients with uncontrolled T2DM (72.2% men) with a mean HbA1c of 8.1%. The HbA1c was significantly decreased in both groups, with no significant difference between the groups. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly increased the LnRHI. The changes in the LnRHI were significantly greater in the dapagliflozin group than in the non-SGLT2 inhibitor group. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly decreased the abdominal visceral fat area, subcutaneous fat area (SFA), and total fat area (TFA) as assessed by CT and significantly increased the plasma adiponectin levels. The percentage changes in the LnRHI were significantly correlated with changes in the SFA, TFA, systolic blood pressure, and adiponectin. Conclusion Add-on treatment with dapagliflozin significantly improves the glycemic control and endothelial function associated with a reduction in the abdominal fat mass in patients with uncontrolled T2DM.

SGLT-2 Inhibitors and Peripheral Artery Disease: A Statistical Hoax or Reality?

Inhibitors of sodium-glucose cotransporters type-2 are the most recent addition to the armamentarium of oral antidiabetic agents. This class of drugs has shown promising results in glycemic control and most importantly to reduce cardiovascular disease (CVD) mortality risk. Despite the encouraging data, there is concern regarding their potential for causing or worsening peripheral artery disease (PAD), which may increase the risk of lower extremity amputations. Following the publication of results of CANVAS and CANVAS-R trials, which revealed that leg and mid-foot amputations occurred about twice as often in patients treated with canagliflozin compared to placebo, the Food and Drug Administration (FDA) in the United States issued a black box warning of leg and foot amputations associated with canagliflozin use. In this article, our main aim is to review the available evidence in preclinical and clinical studies regarding SGLT-2 inhibitors and PAD events, the possible mechanisms related to increased risk of amputation, to evaluate whether it is a class effect or individual drug effect, and most importantly, implications for their continued use as antidiabetic agents. It also raises the issue of including PAD events among the end-points when assessing future antihyperglycemic agents. Thus, we also tried to analyze whether outcomes of SGLT2 inhibitors trials mostly focused on stroke, myocardial infarction, heart failure, and peripheral vascular disease-related outcomes remained underrated.

Exploring novel pharmacotherapeutic applications and repurposing potential of sodium glucose CoTransporter 2 inhibitors

Sodium glucose cotransporter 2 (SGLT2) inhibitors are a relatively new class of anti-hyperglycaemic drugs with a distinctive mechanism of action focusing on renal absorption of glucose. Apart from its anti-hyperglycaemic effects, a multitude of research studies on this class have revealed that these drugs have far more versatile and comprehensive pharmacological effects than previously believed. Approximately 30% of FDA approved drugs are repurposed and used for indications other than those for which they were initially intended. Repurposing already approved drugs leads to significant reduction in pre-clinical and clinical R&D costs as well as minimizing the burden with respect to obtaining regulatory approval. SGLT2 inhibitors have been found to exhibit cardioprotective, renoprotective, anti-hyperlipidaemic, anti-atherosclerotic, anti-obesity, anti-neoplastic, hepatoprotective, and renoprotective effects in in vitro, pre-clinical, and clinical studies. The pleiotropic effects of this class have been attributed to a variety of its pharmacodynamic actions such as natriuresis, haemoconcentration, deactivation of RAAS, ketone body formation, alterations in energy homeostasis, glycosuria, lipolysis, anti-inflammatory, and anti-oxidative actions. These favourable observations encourage further research on this multifaceted class in order to effectively explore and harness its full potential and consequently lead to clinical outcomes.

Adverse Drug Events Associated with Low-Dose (10 mg) Versus High-Dose (25 mg) Empagliflozin in Patients Treated for Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Empagliflozin is a new, emerging oral hypoglycemic agent (OHA) which has shown significant benefits in type 2 diabetes mellitus (T2DM) patients with cardiovascular disease. In this analysis, our aim was to systematically compare the adverse drug events (ADEs) associated with a low (10 mg) versus a high (25 mg) dose of empagliflozin as (1) monotherapy, (2) as an add-on to other OHAs, and (3) as an add-on specifically to metformin, in patients who were treated for T2DM.

METHODS

This was a systematic review and meta-analysis of randomized controlled trials that compared empagliflozin 10 mg versus 25 mg in patients who were treated for T2DM and which reported adverse drug reactions as their clinical endpoints. Statistical analysis was carried out using the latest version of the RevMan software (ver. 5.3) whereby odds ratios (OR) and 95% confidence intervals (CI) were generated.

RESULTS

Eight trials with a total number of 8514 patients treated for T2DM were included in this meta-analysis and systematic review, of whom 4261 patients received 10 mg empagliflozin and 4253 patients received 25 mg empagliflozin. Our results showed that there were no significant differences between the patients with T2DM receiving 10 empagliflozin and those receiving 25 mg empagliflozin in terms of drug-related adverse effects (OR 1.06, 95% CI 0.93-1.21; P = 0.40, I² = 0%), adverse events leading to drug discontinuation (OR 0.99, 95% CI 0.86-1.14; P = 0.87, I² = 0%), and serious adverse events (OR 1.06, 95% CI 0.95-1.18; P = 0.31, I² = 0%) when empagliflozin was provided as monotherapy or as an add-on to other anti-diabetic medications. The same results were obtained when empagliflozin was used as an add-on to metformin or as monotherapy. The duration of the follow-up periods did not affect the results. However, the incidence of genital and urinary tract infections (UTIs) was significantly higher in female patients than in male patients with 10 or 25 mg empagliflozin.

CONCLUSIONS

The incidence of ADEs was not significantly different in T2DM patients receiving 10 versus 25 mg empagliflozin as monotherapy or as add-on to metformin or other anti-diabetic drugs during a shorter or longer follow-up period. However, genital and UTIs were more common in female patients with T2DM irrespective of empagliflozin dosage.

Cardiovascular effects of sodium glucose cotransporter 2 inhibitors

As the first cardiovascular (CV) outcome trial of a glucose-lowering agent to demonstrate a reduction in the risk of CV events in patients with type 2 diabetes mellitus (T2DM), the EMPAgliflozin Removal of Excess Glucose: Cardiovascular OUTCOME Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME^®) trial, which investigated the sodium glucose cotransporter 2 (SGLT2) inhibitor empagliflozin, has generated great interest among health care professionals. CV outcomes data for another SGLT2 inhibitor, canagliflozin, have been published recently in the CANagliflozin CardioVascular Assessment Study (CANVAS) Program, as have CV data from the retrospective real-world study Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors (CVD-REAL), which compared SGLT2 inhibitors with other classes of glucose-lowering drugs. This review discusses the results of these three studies and, with a focus on EMPA-REG OUTCOME, examines the possible mechanisms by which SGLT2 inhibitors may reduce CV risk in patients with T2DM.

Targeting Mitochondrial Calcium Handling and Reactive Oxygen Species in Heart Failure

PURPOSE OF REVIEW

In highly prevalent cardiac diseases, new therapeutic approaches are needed. Since the first description of oxidative stress in heart failure, reactive oxygen species (ROS) have been considered as attractive drug targets. Though clinical trials evaluating antioxidant vitamins as ROS-scavenging agents yielded neutral results in patients at cardiovascular risk, the knowledge of ROS as pathophysiological factors has considerably advanced in the past few years and led to novel treatment approaches. Here, we review recent new insights and current strategies in targeting mitochondrial calcium handling and ROS in heart failure.

RECENT FINDINGS

Mitochondria are an important ROS source, and more recently, drug development focused on targeting mitochondria (e.g. by SS-31 or MitoQ). Important advancement has also been made to decipher how the matching of energy supply and demand through calcium (Ca²⁺) handling impacts on mitochondrial ROS production and elimination. This opens novel opportunities to ameliorate mitochondrial dysfunction in heart failure by targeting cytosolic and mitochondrial ion transporters to improve this matching process. According to this approach, highly specific substances as the preclinical CGP-37157, as well as the clinically used ranolazine and empagliflozin, provide promising results on different levels of evidence. Furthermore, the understanding of redox signalling relays, resembled by catalyst-mediated protein oxidation, is about to change former paradigms of ROS signalling. Novel methods, as redox proteomics, allow to precisely analyse key regulatory thiol switches, which may induce adaptive or maladaptive signalling. Additionally, the generation of genetically encoded probes increased the spatial and temporal resolution of ROS imaging and opened a new methodological window to subtle, formerly obscured processes. These novel insights may broaden our understanding of why previous attempts to target oxidative stress have failed, and at the same time provide us with new targets for drug development.