Empagliflozin ameliorates endothelial dysfunction and suppresses atherogenesis in diabetic apolipoprotein E-deficient mice

Longitudinal assessment of coronary plaque regression related to sodium-glucose cotransporter-2 inhibitor using coronary computed tomography angiography

BACKGROUND

Sodium-Glucose Cotransporter-2 Inhibitor (SGLT2i) is a novel oral drug for treating type 2 diabetes mellitus (T2DM) with demonstrated cardiovascular benefits. Previous studies in apolipoprotein E knockout mice have shown that SGLT2i is associated with attenuated progression of atherosclerosis. However, whether this effect extends to T2DM patients with coronary atherosclerosis in real-world settings remains unknown.

METHODS

In this longitudinal cohort study using coronary computed tomography angiography (CCTA), T2DM patients who underwent ≥ 2 CCTA examinations at our center between 2019 and 2022 were screened. Eligible patients had multiple study plaques, defined as non-obstructive stenosis at baseline and not intervened during serial CCTAs. Exclusion criteria included a CCTA time interval < 12 months, prior SGLT2i treatment, or initiation/discontinuation of SGLT2i during serial CCTAs. Plaque volume (PV) and percent atheroma volume (PAV) were measured for each study plaque using CCTA plaque analysis software. Patients and plaques were categorized based on SGLT2i therapy and compared using a 1:1 propensity score matching (PSM) analysis.

RESULTS

The study included 236 patients (mean age 60.5 ± 9.5 years; 69.1% male) with 435 study plaques (diameter stenosis ≥ 50%, 31.7%). Following SGLT2i treatment for a median duration of 14.6 (interquartile range: 13.0, 20.0) months, overall, non-calcified, and low-attenuation PV and PAV were significantly decreased, while calcified PV and PAV were increased (all p < 0.001). Meanwhile, reductions in overall PV, non-calcified PV, overall PAV, and non-calcified PAV were significantly greater in SGLT2i-treated compared to non-SGLT2i-treated plaques (all p < 0.001). PSM analysis showed that SGLT2i treatment was associated with higher reductions in overall PV (- 11.77 mm3 vs. 4.33 mm3, p = 0.005), non-calcified PV (- 16.96 mm3 vs. - 1.81 mm3, p = 0.017), overall PAV (- 2.83% vs. 3.36%, p < 0.001), and non-calcified PAV (- 4.60% vs. 0.70%, p = 0.003). These findings remained consistent when assessing annual changes in overall and compositional PV and PAV. Multivariate regression models demonstrated that SGLT2i therapy was associated with attenuated progression of overall or non-calcified PV or PAV, even after adjusting for cardiovascular risk factors, medications, and baseline overall or non-calcified PV or PAV, respectively (all p < 0.05). The effect of SGLT2i on attenuating non-calcified plaque progression was consistent across subgroups (all p for interaction > 0.05).

CONCLUSIONS

In this longitudinal CCTA cohort of T2DM patients, SGLT2i therapy markedly regressed coronary overall PV and PAV, mainly result from a significant reduction in non-calcified plaque.

Endothelial Protection by Sodium-Glucose Cotransporter 2 Inhibitors: A Literature Review of In Vitro and In Vivo Studies

Endothelial dysfunction often precedes the development of cardiovascular diseases, including heart failure. The cardioprotective benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2is) could be explained by their favorable impact on the endothelium. In this review, we summarize the current knowledge on the direct in vitro effects of SGLT2is on endothelial cells, as well as the systematic observations in preclinical models. Four putative mechanisms are explored: oxidative stress, nitric oxide (NO)-mediated pathways, inflammation, and endothelial cell survival and proliferation. Both in vitro and in vivo studies suggest that SGLT2is share a class effect on attenuating reactive oxygen species (ROS) and on enhancing the NO bioavailability by increasing endothelial nitric oxide synthase activity and by reducing NO scavenging by ROS. Moreover, SGLT2is significantly suppress inflammation by preventing endothelial expression of adhesion receptors and pro-inflammatory chemokines in vivo, indicating another class effect for endothelial protection. However, in vitro studies have not consistently shown regulation of adhesion molecule expression by SGLT2is. While SGLT2is improve endothelial cell survival under cell death-inducing stimuli, their impact on angiogenesis remains uncertain. Further experimental studies are required to accurately determine the interplay among these mechanisms in various cardiovascular complications, including heart failure and acute myocardial infarction.

Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitors and Cardiovascular Outcomes: A Review of Literature

Coronary arterial diseases are a major contributor to disease and death worldwide and are most often compounded by several other underlying medical conditions. A key concern is type 2 diabetes mellitus (T2DM). Despite progress in medical advancements, these life-threatening illnesses are still underdiagnosed and undermanaged. A relatively newer class of anti-diabetic drugs, the sodium-glucose cotransporter-2 inhibitors (SGL2-Is), also termed gliflozins, have shown promising results in reducing cardiovascular risk, regardless of diabetic status. These drugs have on-target (promoting renal glycosuria and diuresis by acting on the SGLT-2 channels in the proximal convoluted tubule) and off-target effects contributing to the reported cardiovascular benefit. Some emerging theories about its impact on myocardial energetics, calcium balance, and renal physiology exist. In this review article, we explored three major cardiovascular outcome trials: the Dapagliflozin Effect on Cardiovascular Events-Thrombolysis in Myocardial Infarction 58 (DECLARE-TIMI 58) trial, the CANagliflozin cardioVascular Assessment Study (CANVAS) program, and the Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients-Removing Excess Glucose (EMPA-REG OUTCOME) trial to evaluate the cardiovascular effects of SGLT2-Is.

The current landscape for diabetes treatment: Preventing diabetes-associated CV risk

Despite the risk of atherosclerosis has progressively declined over the past few decades, subjects with type 2 diabetes mellitus (T2DM) continue to experience substantial excess of atherosclerotic cardiovascular disease (ASCVD)-related events. Therefore, there is urgent need to treat ASCVD disease in T2DM earlier, more intensively, and with greater precision. Many factors concur to increase the risk of atherosclerosis, and multifactorial intervention remains the basis for effective prevention or reduction of atherosclerotic events. The role of anti-hyperglycemic medications in reducing the risk of ASCVD in subjects with T2DM has evolved over the past few years. Multiple cardiovascular outcome trials (CVOTs) with new and emerging glucose-lowering agents, namely SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP1-RA), have demonstrated significant reductions of major cardiovascular events and additional benefits. This robust evidence has changed the landscape for managing people with T2DM. In addition to glycemic and ancillary extra-glycemic properties, SGLT2i and GLP1-RA might exert favorable effects on subclinical and clinical atherosclerosis. Therefore, the objective of this review is to discuss the available evidence supporting anti-atherosclerotic properties of SGLT2i and GLP1-RA, with a quick nod to sotagliflozin and tirzepatide.

SGLT1 and SGLT2 inhibition, circulating metabolites, and cerebral small vessel disease: a mediation Mendelian Randomization study

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) and SGLT1 inhibitors may have additional beneficial metabolic effects on circulating metabolites beyond glucose regulation, which could contribute to a reduction in the burden of cerebral small vessel disease (CSVD). Accordingly, we used Mendelian Randomization (MR) to examine the role of circulating metabolites in mediating SGLT2 and SGLT1 inhibition in CSVD.

METHODS

Genetic instruments for SGLT1/2 inhibition were identified as genetic variants, which were both associated with the expression of encoding genes of SGLT1/2 inhibitors and glycated hemoglobin A1c (HbA1c) level. A two-sample two-step MR was used to determine the causal effects of SGLT1/2 inhibition on CSVD manifestations and the mediating effects of 1400 circulating metabolites linking SGLT1/2 inhibition with CSVD manifestations.

RESULTS

A lower risk of deep cerebral microbleeds (CMBs) and small vessel stroke (SVS) was linked to genetically predicted SGLT2 inhibition. Better white matter structure integrity was also achieved, as evidenced by decreased mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), as well as lower deep (DWMH) and periventrivular white matter hyperintensity (PWMH) volume. Inhibiting SGLT2 could also lessen the incidence of severe enlarged perivascular spaces (EPVS) located at white matter, basal ganglia (BG) and hippocampus (HIP). SGLT1 inhibition could preserve white matter integrity, shown as decreased MD of white matter and DWMH volume. The effect of SGLT2 inhibition on SVS and MD of white matter through the concentration of 4-acetamidobutanoate and the cholesterol to oleoyl-linoleoyl-glycerol (18:1 to 18:2) ratio, with a mediated proportion of 30.3% and 35.5% of the total effect, respectively.

CONCLUSIONS

SGLT2 and SGLT1 inhibition play protective roles in CSVD development. The SGLT2 inhibition could lower the risk of SVS and improve the integrity of white matter microstructure via modulating the level of 4-acetamidobutanoate and cholesterol metabolism. Further mechanistic and clinical studies research are needed to validate our findings.

Investigating the impact of empagliflozin on the retina of diabetic mice

BACKGROUND

Diabetic retinopathy (DR) frequently results in compromised visual function, with hyperglycemia-induced disruption of the blood-retinal barrier (BRB) through various pathways as a critical mechanism. Existing DR treatments fail to address early and potentially reversible microvascular alterations. This study examined the effects of empagliflozin (EMPA), a selective Sodium-glucose transporter 2 (SGLT2) inhibitor, on the retina of db/db mice. The objective of this study is to investigate the potential role of EMPA in the prevention and delay of DR.

METHODS

db/db mice were randomly assigned to either the EMPA treatment group (db/db + Emp) or the model group (db/db), while C57 mice served as the normal control group (C57). Mice in the db/db + Emp group received EMPA for eight weeks. Body weight, fasting blood glucose (FBG), and blood VEGF were subsequently measured in all mice, along with the detection of specific inflammatory factors and BRB proteins in the retina. Retinal SGLT2 protein expression was compared using immunohistochemical analysis, and BRB structural changes were observed via electron microscopy.

RESULTS

EMPA reduced FBG, blood VEGF, and retinal inflammatory factors TNF-α, IL-6, and VEGF levels in the eye tissues of db/db mice. EMPA also increased Claudin-1, Occludin-1, and ZO-1 levels while decreasing ICAM-1 and Fibronectin, thereby preserving BRB function in db/db mice. Immunohistochemistry revealed that EMPA reduced SGLT2 expression in the retina of diabetic mice, and electron microscopy demonstrated that EMPA diminished tight junction damage between retinal vascular endothelial cells and prevented retinal vascular basement membrane thickening in diabetic mice.

CONCLUSION

EMPA mitigates inflammation and preserves BRB structure and function, suggesting that it may prevent DR or serve as an effective early treatment for DR.

Methylglyoxal and Advanced Glycation End Products (AGEs): Targets for the Prevention and Treatment of Diabetes-Associated Bladder Dysfunction?

Methylglyoxal (MGO) is a highly reactive α-dicarbonyl compound formed endogenously from 3-carbon glycolytic intermediates. Methylglyoxal accumulated in plasma and urine of hyperglycemic and diabetic individuals acts as a potent peptide glycation molecule, giving rise to advanced glycation end products (AGEs) like arginine-derived hydroimidazolone (MG-H1) and carboxyethyl-lysine (CEL). Methylglyoxal-derived AGEs exert their effects mostly via activation of RAGE, a cell surface receptor that initiates multiple intracellular signaling pathways, favoring a pro-oxidant environment through NADPH oxidase activation and generation of high levels of reactive oxygen species (ROS). Diabetic bladder dysfunction is a bothersome urological complication in patients with poorly controlled diabetes mellitus and may comprise overactive bladder, urge incontinence, poor emptying, dribbling, incomplete emptying of the bladder, and urinary retention. Preclinical models of type 1 and type 2 diabetes have further confirmed the relationship between diabetes and voiding dysfunction. Interestingly, healthy mice supplemented with MGO for prolonged periods exhibit in vivo and in vitro bladder dysfunction, which is accompanied by increased AGE formation and RAGE expression, as well as by ROS overproduction in bladder tissues. Drugs reported to scavenge MGO and to inactivate AGEs like metformin, polyphenols, and alagebrium (ALT-711) have shown favorable outcomes on bladder dysfunction in diabetic obese leptin-deficient and MGO-exposed mice. Therefore, MGO, AGEs, and RAGE levels may be critically involved in the pathogenesis of bladder dysfunction in diabetic individuals. However, there are no clinical trials designed to test drugs that selectively inhibit the MGO-AGEs-RAGE signaling, aiming to reduce the manifestations of diabetes-associated bladder dysfunction. This review summarizes the current literature on the role of MGO-AGEs-RAGE-ROS axis in diabetes-associated bladder dysfunction. Drugs that directly inactivate MGO and ameliorate bladder dysfunction are also reviewed here.

Endothelial dysfunction in vascular complications of diabetes: a comprehensive review of mechanisms and implications

Diabetic vascular complications are prevalent and severe among diabetic patients, profoundly affecting both their quality of life and long-term prospects. These complications can be classified into macrovascular and microvascular complications. Under the impact of risk factors such as elevated blood glucose, blood pressure, and cholesterol lipids, the vascular endothelium undergoes endothelial dysfunction, characterized by increased inflammation and oxidative stress, decreased NO biosynthesis, endothelial-mesenchymal transition, senescence, and even cell death. These processes will ultimately lead to macrovascular and microvascular diseases, with macrovascular diseases mainly characterized by atherosclerosis (AS) and microvascular diseases mainly characterized by thickening of the basement membrane. It further indicates a primary contributor to the elevated morbidity and mortality observed in individuals with diabetes. In this review, we will delve into the intricate mechanisms that drive endothelial dysfunction during diabetes progression and its associated vascular complications. Furthermore, we will outline various pharmacotherapies targeting diabetic endothelial dysfunction in the hope of accelerating effective therapeutic drug discovery for early control of diabetes and its vascular complications.

Effects of Glucagon-Like Peptide-1 Receptor Agonists and Sodium-Glucose Cotransporter 2 Inhibitors on Intima-Media Thickness: Systematic Review and Meta-Analysis

Background

Beyond glycemic control, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2is) have been proposed to reduce the risk of cardiovascular events. The aim of the present systematic review and meta-analysis is to demonstrate the effects of GLP-1 RA and SGLT2is on intima-media thickness (IMT).

Methods

PubMed, EMBASE, Web of Science, SCOPUS, and Google Scholar databases were searched from inception to September 9, 2023. All interventional and observational studies that provided data on the effects of GLP-1 RAs or SGLT2is on IMT were included. Critical appraisal was performed using the Joanna Briggs Institute checklists. IMT changes (preintervention and postintervention) were pooled and meta-analyzed using a random-effects model. Subgroup analyses were based on type of medication (GLP-1 RA: liraglutide and exenatide; SGLT2i: empagliflozin, ipragliflozin, tofogliflozin, and dapagliflozin), randomized clinical trials (RCTs), and diabetic patients.

Results

The literature search yielded 708 related articles after duplicates were removed. Eighteen studies examined the effects of GLP-1 RA, and eleven examined the effects of SGLT2i. GLP-1 RA and SGLT2i significantly decreased IMT (MD = -0.123, 95% CI (-0.170, -0.076), P < 0.0001, I2 = 98% and MD = -0.048, 95% CI (-0.092, -0.004), P = 0.031, I2 = 95%, respectively). Metaregression showed that IMT change correlated with baseline IMT, whereas it did not correlate with gender, duration of diabetes, and duration of treatment.

Conclusions

Treatment with GLP-1 RA and SGLT2i can lower IMT in diabetic patients, and GLP-1 RA may be more effective than SGLT2i.

Diabetes Mellitus to Accelerated Atherosclerosis: Shared Cellular and Molecular Mechanisms in Glucose and Lipid Metabolism

Diabetes is one of the critical independent risk factors for the progression of cardiovascular disease, and the underlying mechanism regarding this association remains poorly understood. Hence, it is urgent to decipher the fundamental pathophysiology and consequently provide new insights into the identification of innovative therapeutic targets for diabetic atherosclerosis. It is now appreciated that different cell types are heavily involved in the progress of diabetic atherosclerosis, including endothelial cells, macrophages, vascular smooth muscle cells, dependence on altered metabolic pathways, intracellular lipids, and high glucose. Additionally, extensive studies have elucidated that diabetes accelerates the odds of atherosclerosis with the explanation that these two chronic disorders share some common mechanisms, such as endothelial dysfunction and inflammation. In this review, we initially summarize the current research and proposed mechanisms and then highlight the role of these three cell types in diabetes-accelerated atherosclerosis and finally establish the mechanism pinpointing the relationship between diabetes and atherosclerosis.

Sodium-Glucose Cotransporter Protein 2 Inhibitors: Novel Application for the Treatment of Obesity-Associated Hypertension

Obesity is becoming increasingly prevalent in China and worldwide and is closely related to the development of hypertension. The pathophysiology of obesity-associated hypertension is complex, including an overactive sympathetic nervous system (SNS), activation of the renin-angiotensin-aldosterone system (RAAS), insulin resistance, hyperleptinemia, renal dysfunction, inflammatory responses, and endothelial function, which complicates treatment. Sodium-glucose cotransporter protein 2 (SGLT-2) inhibitors, novel hypoglycemic agents, have been shown to reduce body weight and blood pressure and may serve as potential novel agents for the treatment of obesity-associated hypertension. This review discusses the beneficial mechanisms of SGLT-2 inhibitors for the treatment of obesity-associated hypertension. SGLT-2 inhibitors can inhibit SNS activity, reduce RAAS activation, ameliorate insulin resistance, reduce leptin secretion, improve renal function, and inhibit inflammatory responses. SGLT-2 inhibitors can, therefore, simultaneously target multiple mechanisms of obesity-associated hypertension and may serve as an effective treatment for obesity-associated hypertension.

Empagliflozin reduces endoplasmic reticulum stress associated TXNIP/NLRP3 activation in tunicamycin-stimulated aortic endothelial cells

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have proven to be of therapeutic significance for cardiovascular diseases beyond the treatment of type 2 diabetes. Recent studies have demonstrated the beneficial effects of SGLT2i on endothelial cell (EC) dysfunction, but the underlying cellular mechanisms remain to be clarified. In this study, we sought to understand the effect of empagliflozin (EMPA; Jardiance®) on cell homeostasis and endoplasmic reticulum (ER) stress signaling. ER stress was induced by tunicamycin (Tm) in human abdominal aortic ECs treated with EMPA over 24 h. Tm-induced ER stress caused increases in the protein expression of thioredoxin interacting protein (TXNIP), NLR-family pyrin domain-containing protein 3 (NLRP3), C/EBP homologous protein (CHOP), and in the ratio of phospho-eIF2α/eIF2α. EMPA (50-100 µM) resulted in a dampened downstream activation of ER stress as seen by the reduced expression of CHOP and TXNIP/NLRP3 in a dose-dependent manner. Nuclear factor erythroid 2-related factor 2 (nrf2) translocation was also attenuated in EMPA-treated ECs. These results suggest that EMPA improves redox signaling under ER stress which in turn attenuates the activation of TXNIP/NLRP3.

The effect of SGLT2 inhibitors on the endothelium and the microcirculation: from bench to bedside and beyond

AIMS

The beneficial cardiovascular effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors irrespective of the presence of diabetes mellitus are nowadays well established and they already constitute a significant pillar for the management of heart failure, irrespective of the ejection fraction. The exact underlying mechanisms accountable for these effects, however, remain largely unknown. The direct effect on endothelial function and microcirculation is one of the most well studied. The broad range of studies presented in this review aims to link all available data from the bench to bedside and highlight the existing gaps as well as the future directions in the investigations concerning the effects of SGLT2 inhibitors on the endothelium and the microcirculation.

METHODS AND RESULTS

An extensive search has been conducted using the MEDLINE/PubMed database in order to identify the relevant studies. Preclinical data suggest that SGLT2 inhibitors directly affect endothelial function independently of glucose and specifically via several interplaying molecular pathways, resulting in improved vasodilation, increased NO production, enhanced mitochondrial homeostasis, endothelial cell viability, and angiogenesis as well as attenuation of oxidative stress and inflammation. Clinical data systematically confirm this beneficial effect on the endothelium, whereas the evidence concerning the effect on the microcirculation is conflicting.

CONCLUSION

Preclinical and clinical studies indicate that SGLT2 inhibitors attenuate endothelial and microvascular dysfunction via a combination of mechanisms, which play a role in their beneficial cardiovascular effect.

The anti-inflammatory and immunological properties of SGLT-2 inhibitors

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) are antidiabetic oral drugs that act on proximal renal tubules promoting renal glucose excretion. Although SGLT-2i belong to the class of hypoglycemic agents, in the last years great interest has emerged in studying their pleiotropic effects, beyond their ability to lower glucose levels.

PURPOSE

In this review we are describing the anti-inflammatory and immunological properties of SGLT-2i; furthermore, we are addressing how the mechanisms associated with the aforementioned anti-inflammatory properties may contribute to the beneficial effects of SGLT-2i in diabetes.

METHODS

A systematic search was undertaken for studies related the properties of SGLT-2i in reducing the inflammatory milieu of acute and chronic disease by acting on the immune system, independently by glycemia.

RESULTS

Recently, some data described the anti-inflammatory and immunological properties of SGLT-2 in both pre-clinical and clinical studies. Numerous data confirmed the cardio- and -renal protective effects of SGLT-2i in patients with heart failure and kidney diseases, with or without diabetes.

CONCLUSIONS

SGLT-2i are promising drugs with anti-inflammatory and immunological properties. Despite the mechanism of action of SGLT-2i is not fully understood, these drugs demonstrated anti-inflammatory effects, which may help in keeping under control the variety of complications associated with diabetes.

The Role of Perivascular Adipose Tissue in the Pathogenesis of Endothelial Dysfunction in Cardiovascular Diseases and Type 2 Diabetes Mellitus

Cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2DM) are two of the four major chronic non-communicable diseases (NCDs) representing the leading cause of death worldwide. Several studies demonstrate that endothelial dysfunction (ED) plays a central role in the pathogenesis of these chronic diseases. Although it is well known that systemic chronic inflammation and oxidative stress are primarily involved in the development of ED, recent studies have shown that perivascular adipose tissue (PVAT) is implicated in its pathogenesis, also contributing to the progression of atherosclerosis and to insulin resistance (IR). In this review, we describe the relationship between PVAT and ED, and we also analyse the role of PVAT in the pathogenesis of CVDs and T2DM, further assessing its potential therapeutic target with the aim of restoring normal ED and reducing global cardiovascular risk.

Adding SGLT2 Cotransporter Inhibitor to PPARγ Activator Does Not Provide an Additive Effect in the Management of Diabetes-Induced Vascular Dysfunction

INTRODUCTION

Endothelial dysfunction (ED) plays a key role in the pathogenesis of diabetic vascular complications. In monotherapy, dapagliflozin (Dapa) as well as pioglitazone (Pio) prevent the progression of target organ damage in both type 1 (T1DM) and type 2 diabetes. We investigated whether the simultaneous PPAR-γ activation and SGLT2 cotransporter inhibition significantly alleviate ED-related pathological processes and thus normalize vascular response in experimental T1DM.

METHODS

Experimental diabetes was induced by streptozotocin (STZ; 55 mg/kg, i.p.) in Wistar rats. Dapa (10 mg/kg), Pio (12 mg/kg), or their combination were administrated to the STZ rats orally. Six weeks after STZ administration, the aorta was excised for functional studies and real-time qPCR analysis.

RESULTS

In the aorta of diabetic rats, impaired endothelium-dependent and independent relaxation were accompanied by the imbalance between vasoactive factors (eNos, Et1) and overexpression of inflammation (Tnfα, Il1b, Il6, Icam, Vcam) and oxidative stress (Cybb) markers. Pio monotherapy normalized response to vasoactive substances and restored balance between Et1-eNos expression, while Dapa treatment was ineffective. Nevertheless, Dapa and Pio monotherapy significantly reverted inflammation and oxidative stress markers to normal values. The combination treatment exhibited an additive effect in modulating Il6 expression, reaching the effect of Pio monotherapy in other measured parameters.

CONCLUSION

Particularly, Pio exerts a vasoprotective character when used in monotherapy. When combined with Dapa, it does not exhibit an expected additive effect within modulating vasoreactivity or oxidative stress, though having a significant influence on IL6 downregulation.

Cathepsin S inhibition in dendritic cells prevents Th17 cell differentiation in perivascular adipose tissues following vascular injury in diabetic rats

In the context of diabetes mellitus (DM), the circulating cathepsin S (CTSS) level is significantly higher in the cardiovascular disease group. Therefore, this study was designed to investigate the role of CTSS in restenosis following carotid injury in diabetic rats. To induce DM, 60 mg/kg of streptozotocin (STZ) in citrate buffer was injected intraperitoneally into Sprague-Dawley rats. After successful modeling of DM, wire injury of the rat carotid artery was performed, followed by adenovirus transduction. Levels of blood glucose and Th17 cell surface antigens including ROR-γt, IL-17A, IL-17F, IL-22, and IL-23 in perivascular adipose tissues (PVAT) were evaluated. For in vitro analysis, human dendritic cells (DCs) were treated with 5.6-25 mM glucose for 24 h. The morphology of DCs was observed using an optical microscope. CD4+ T cells derived from human peripheral blood mononuclear cells were cocultured with DCs for 5 days. Levels of IL-6, CTSS, ROR-γt, IL-17A, IL-17F, IL-22 and IL-23 were measured. Flow cytometry was conducted to detect DC surface biomarkers (CD1a, CD83, and CD86) and Th17 cell differentiation. The collected DCs presented a treelike shape and were positive for CD1a, CD83, and CD86. Glucose impaired DC viability at the dose of 35 mM. Glucose treatment led to an increase in CTSS and IL-6 expression in DCs. Glucose-treated DCs promoted the differentiation of Th17 cells. CTSS depletion downregulated IL-6 expression and inhibited Th17 cell differentiation in vitro and in vivo. CTSS inhibition in DCs inhibits Th17 cell differentiation in PVAT tissues from diabetic rats following vascular injury.

Role of dysfunctional peri-organ adipose tissue in metabolic disease

Metabolic disease is a complex disorder defined by a group with interrelated factors. There is growing evidence that obesity can lead to a variety of metabolic diseases, including diabetes and cardiovascular disease. Excessive adipose tissue (AT) deposition and ectopic accumulation can lead to increased peri-organ AT thickness. Dysregulation of peri-organ (perivascular, perirenal, and epicardial) AT is strongly associated with metabolic disease and its complications. The mechanisms include secretion of cytokines, activation of immunocytes, infiltration of inflammatory cells, involvement of stromal cells, and abnormal miRNA expression. This review discusses the associations and mechanisms by which various types of peri-organ AT affect metabolic diseases while addressing it as a potential future treatment strategy.

Canagliflozin Ameliorates Oxidative Stress and Autistic-like Features in Valproic-Acid-Induced Autism in Rats: Comparison with Aripiprazole Action

Based on their proven anti-inflammatory and antioxidant effects, recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental disorders such as autism spectrum disorder (ASD). Therefore, the aim of this study is to assess the effects of subchronic systemic treatment with intraperitoneal (i.p.) canagliflozin (20, 50, and 100 mg/kg) compared to aripiprazole (ARP) (3 mg/g, i.p.) in a valproic acid (VPA)-induced rat model of autism. The behavioral characteristics of ASD, oxidative stress, and acetylcholinesterase (AChE) activity in rats with ASD-like behaviors, which were induced by prenatal exposure to VPA, were evaluated. The behavioral assessment methods used for this study were the open field test (OFT), the marble-burying test (MBT), and the nestlet-shredding test (NST) to examine their exploratory, anxiety, and compulsiveness-like actions, while the biochemical assessment used for this study was an ELISA colorimetric assay to measure ASD biomarker activity in the hippocampus, prefrontal cortex, and cerebellum. Rats that were pretreated with 100 mg/kg of canagliflozin displayed a significantly lower percentage of shredding (1.12 ± 0.6%, p < 0.01) compared to the ARP group (3.52 ± 1.6%). Pretreatment with (20 mg/kg, 50 mg/kg, and 100 mg/kg) canagliflozin reversed anxiety levels and hyperactivity and reduced hyper-locomotor activity significantly (161 ± 34.9 s, p < 0.05; 154 ± 44.7 s, p < 0.05; 147 ± 33.6 s, p < 0.05) when compared with the VPA group (303 ± 140 s). Moreover, canagliflozin and ARP mitigated oxidative stress status by restoring levels of glutathione (GSH) and catalase (CAT) and increasing the levels of malondialdehyde (MDA) in all tested brain regions. The observed results propose repurposing of canagliflozin in the therapeutic management of ASD. However, further investigations are still required to verify the clinical relevance of canagliflozin in ASD.

Perspective of SGLT2i in the Treatment of Abdominal Aortic Aneurysms

ABSTRACT

The incidence of abdominal aortic aneurysm (AAA) in the elderly is increasing year by year with high mortality. Current treatment is mainly through surgery or endovascular intervention, which is not sufficient to reduce future risk. Therefore, we still need to find an effective conservative measure as an adjunct therapy or early intervention to prevent AAA progression. Traditional therapeutic agents, such as β-receptor blockers, calcium channel blockers, and statins, have been shown to have limited effects on the growth of AAA. Recently, sodium-glucose cotransport proteins inhibitors (SGLT2is), a new class hypoglycemic drug, have shown outstanding beneficiary effects on cardiovascular diseases by plasma volume reduction, vascular tone regulation, and various unidentified mechanisms. It has been demonstrated that SGLT2i is abundantly expressed in the aorta, and some studies also showed promising results of SGLT2i in treating animal AAA models. This article aims to summarize the recent progress of AAA studies and look forward to the application of SGLT2i in AAA treatment for early intervention or adjunct therapy after surgical repair or stent graft.

The Role of Sodium-Glucose Cotransporter-2 Inhibitors in Heart Failure Management: The Continuing Challenge of Clinical Outcome Endpoints in Heart Failure Trials

The introduction of sodium-glucose cotransporter-2 (SGLT2) inhibitors in the management of heart failure with preserved ejection fraction (HFpEF) may be regarded as the first effective treatment in these patients. However, this proposition must be evaluated from the perspective of the complexity of clinical outcome endpoints in heart failure. The major goals of heart failure treatment have been categorized as: (1) reduction in (cardiovascular) mortality, (2) prevention of recurrent hospitalizations due to worsening heart failure, and (3) improvement in clinical status, functional capacity, and quality of life. The use of the composite primary endpoint of cardiovascular death and hospitalization for heart failure in SGLT2 inhibitor HFpEF trials flowed from the assumption that hospitalization for heart failure is a proxy for subsequent cardiovascular death. The use of this composite endpoint was not justified since the effect of the intervention on both components was clearly distinct. Moreover, the lack of convincing and clinically meaningful effects of SGLT2 inhibitors on metrics of heart failure-related health status indicates that the effect of this class of drugs in HFpEF patients is essentially restricted to an effect on hospitalization for heart failure. In conclusion, SGLT2 inhibitors do not represent a substantial breakthrough in the management of HFpEF.

Empagliflozin ameliorates atherosclerosis via regulating the intestinal flora

BACKGROUND AND AIMS

Sodium-glucose cotransporter 2 inhibitor (SGLT2i) has been reported to attenuate atherosclerosis. Further, it has been suggested that intestinal flora influences atherosclerosis progression. Herein we aimed to investigate whether SGLT2i can alleviate atherosclerosis through intestinal flora.

METHODS

Six-week-old male ApoE^-/- mice fed a high-fat diet were gavaged either empagliflozin (SGLT2i group, n = 9) or saline (Ctrl group, n = 6) for 12 weeks. Feces were collected from both groups at the end of the experiment for fecal microbiota transplantation (FMT). Another 12 six-week-old male ApoE^-/- mice were fed a high-fat diet and received FMT with feces either from SGLT2i (FMT-SGLT2i group, n = 6) or from Ctrl (FMT-Ctrl group, n = 6) groups. Blood, tissue, and fecal samples were collected for subsequent analyses.

RESULTS

In comparison with Ctrl group, atherosclerosis was less severe in the SGLT2i group (p < 0.0001), and the richness of probiotic, such as f_Coriobacteriaceae, f_S24-7, f_Lachnospiraceae, and f_Adlercreutzia, was higher in feces. Besides, empagliflozin resulted in a significant reduction in the inflammatory response and altered intestinal flora metabolism. Interestingly, compared with FMT-Ctrl, FMT-SGLT2i also showed a reduction in atherosclerosis and systemic inflammatory response, as well as changes in the component of intestinal flora and pertinent metabolites similar to SGLT2i group.

CONCLUSIONS

Empagliflozin seems to mitigate atherosclerosis partly by regulating intestinal microbiota, and this anti-atherosclerotic effect can be transferred through intestinal flora transplantation.

Dapagliflozin improves pancreatic islet function by attenuating microvascular endothelial dysfunction in type 2 diabetes

AIMS

Sodium-glucose co-transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown.

MATERIALS AND METHODS

The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS-1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co-culture with MS-1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined.

RESULTS

Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate-treated MS-1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin-mediated effects. Importantly, dapagliflozin attenuated the palmitate-induced downregulation of ß cell function-related gene expression and insulin secretion in MIN6 cells co-cultured with MS-1 cells but not in those on mono-culture.

CONCLUSIONS

Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin-induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt-mTOR-dependent manner.

The Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitor Empagliflozin Reverses Hyperglycemia-Induced Monocyte and Endothelial Dysfunction Primarily through Glucose Transport-Independent but Redox-Dependent Mechanisms

PURPOSE

Hyperglycaemia-induced oxidative stress and inflammation contribute to vascular cell dysfunction and subsequent cardiovascular events in T2DM. Selective sodium-glucose co-transporter-2 (SGLT-2) inhibitor empagliflozin significantly improves cardiovascular mortality in T2DM patients (EMPA-REG trial). Since SGLT-2 is known to be expressed on cells other than the kidney cells, we investigated the potential ability of empagliflozin to regulate glucose transport and alleviate hyperglycaemia-induced dysfunction of these cells.

METHODS

Primary human monocytes were isolated from the peripheral blood of T2DM patients and healthy individuals. Primary human umbilical vein endothelial cells (HUVECs) and primary human coronary artery endothelial cells (HCAECs), and fetoplacental endothelial cells (HPECs) were used as the EC model cells. Cells were exposed to hyperglycaemic conditions in vitro in 40 ng/mL or 100 ng/mL empagliflozin. The expression levels of the relevant molecules were analysed by RT-qPCR and confirmed by FACS. Glucose uptake assays were carried out with a fluorescent derivative of glucose, 2-NBDG. Reactive oxygen species (ROS) accumulation was measured using the H₂DFFDA method. Monocyte and endothelial cell chemotaxis were measured using modified Boyden chamber assays.

RESULTS

Both primary human monocytes and endothelial cells express SGLT-2. Hyperglycaemic conditions did not significantly alter the SGLT-2 levels in monocytes and ECs in vitro or in T2DM conditions. Glucose uptake assays carried out in the presence of GLUT inhibitors revealed that SGLT-2 inhibition very mildly, but not significantly, suppressed glucose uptake by monocytes and endothelial cells. However, we detected the significant suppression of hyperglycaemia-induced ROS accumulation in monocytes and ECs when empagliflozin was used to inhibit SGLT-2 function. Hyperglycaemic monocytes and endothelial cells readily exhibited impaired chemotaxis behaviour. The co-treatment with empagliflozin reversed the PlGF-1 resistance phenotype of hyperglycaemic monocytes. Similarly, the blunted VEGF-A responses of hyperglycaemic ECs were also restored by empagliflozin, which could be attributed to the restoration of the VEGFR-2 receptor levels on the EC surface. The induction of oxidative stress completely recapitulated most of the aberrant phenotypes exhibited by hyperglycaemic monocytes and endothelial cells, and a general antioxidant N-acetyl-L-cysteine (NAC) was able to mimic the effects of empagliflozin.

CONCLUSIONS

This study provides data indicating the beneficial role of empagliflozin in reversing hyperglycaemia-induced vascular cell dysfunction. Even though both monocytes and endothelial cells express functional SGLT-2, SGLT-2 is not the primary glucose transporter in these cells. Therefore, it seems likely that empagliflozin does not directly prevent hyperglycaemia-mediated enhanced glucotoxicity in these cells by inhibiting glucose uptake. We identified the reduction of oxidative stress by empagliflozin as a primary reason for the improved function of monocytes and endothelial cells in hyperglycaemic conditions. In conclusion, empagliflozin reverses vascular cell dysfunction independent of glucose transport but could partially contribute to its beneficial cardiovascular effects.

The Anti-Inflammatory Effect of Novel Antidiabetic Agents

The incidence of type 2 diabetes (T2DM) has been increasing worldwide and remains one of the leading causes of atherosclerotic disease. Several antidiabetic agents have been introduced in trying to regulate glucose control levels with different mechanisms of action. These agents, and sodium-glucose cotransporter-2 inhibitors in particular, have been endorsed by contemporary guidelines in patients with or without T2DM. Their widespread usage during the last three decades has raised awareness in the scientific community concerning their pleiotropic mechanisms of action, including their putative anti-inflammatory effect. In this review, we delve into the anti-inflammatory role and mechanism of the existing antidiabetic agents in the cardiovascular system and their potential use in other chronic sterile inflammatory conditions.

Sodium-glucose cotransporter 2 inhibitor ameliorates high fat diet-induced hypothalamic-pituitary-ovarian axis disorders

High-fat diet (HFD) consumption is known to be associated with ovulatory disorders among women of reproductive age. Previous studies in animal models suggest that HFD-induced microglia activation contributes to hypothalamic inflammation. This causes the dysfunction of the hypothalamic-pituitary-ovarian (HPO) axis, leading to subfertility. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a novel class of lipid-soluble antidiabetic drugs that target primarily the early proximal tubules in kidney. Recent evidence revealed an additional expression site of SGLT2 in the central nervous system (CNS), indicating a promising role of SGLT2 inhibitors in the CNS. In type 2 diabetes patients and rodent models, SGLT2 inhibitors exhibit neuroprotective properties through reduction of oxidative stress, alleviation of cerebral atherosclerosis and suppression of microglia-induced neuroinflammation. Furthermore, clinical observations in patients with polycystic ovary syndrome (PCOS) demonstrated that SGLT2 inhibitors ameliorated patient anthropometric parameters, body composition and insulin resistance. Therefore, it is of importance to explore the central mechanism of SGLT2 inhibitors in the recovery of reproductive function in patients with PCOS and obesity. Here, we review the hypothalamic inflammatory mechanisms of HFD-induced microglial activation, with a focus on the clinical utility and possible mechanism of SGLT2 inhibitors in promoting reproductive fitness.

Effect of ipragliflozin on carotid intima-media thickness in patients with type 2 diabetes: a multicenter, randomized, controlled trial

AIMS

To examine the effects of a 24-month treatment with ipragliflozin on carotid intima-media thickness (IMT) in type 2 diabetes patients.

METHODS AND RESULTS

In this multicenter, prospective, randomized, open-label, and blinded-endpoint investigator-initiated clinical trial, adults with type 2 diabetes and haemoglobin A1C (HbA1c) of 6.0-10.0% (42-86 mmol/mol) were randomized equally to ipragliflozin (50 mg daily) and non-sodium-glucose cotransporter-2 (SGLT2) inhibitor use of standard-care (control group) for type 2 diabetes and were followed-up to 24 months. The primary endpoint was the change in mean common carotid artery IMT (CCA-IMT) from baseline to 24 months. A total of 482 patients were equally allocated to the ipragliflozin (N = 241) and control (N = 241) groups, and 464 patients (median age 68 years, female 31.7%, median type 2 diabetes duration 8 years, median HbA1c 7.3%) were included in the analyses. For the primary endpoint, the changes in the mean CCA-IMT from baseline to 24 months were 0.0013 [95% confidence interval (CI), -0.0155-0.0182] mm and 0.0015 (95% CI, -0.0155-0.0184) mm in the ipragliflozin and control groups, respectively, with an estimated group difference (ipragliflozin-control) of -0.0001 mm (95% CI, -0.0191-0.0189; P = 0.989). A group difference in HbA1c change at 24 months was also non-significant between the treatment groups [-0.1% (95% CI, -0.2-0.1); P = 0.359].

CONCLUSION

Twenty-four months of ipragliflozin treatment did not affect carotid IMT status in patients with type 2 diabetes recruited in the PROTECT study, relative to the non-SGLT2 inhibitor-use standard care for type 2 diabetes.

Repurposing SGLT2 Inhibitors for Neurological Disorders: A Focus on the Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a substantially increasing incidence rate. It is characterized by repetitive behavior, learning difficulties, deficits in social communication, and interactions. Numerous medications, dietary supplements, and behavioral treatments have been recommended for the management of this condition, however, there is no cure yet. Recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental diseases, based on their proved anti-inflammatory effects, such as downregulating the expression of several proteins, including the transforming growth factor beta (TGF-β), interleukin-6 (IL-6), C-reactive protein (CRP), nuclear factor κB (NF-κB), tumor necrosis factor alpha (TNF-α), and the monocyte chemoattractant protein (MCP-1). Furthermore, numerous previous studies revealed the potential of the SGLT2 inhibitors to provide antioxidant effects, due to their ability to reduce the generation of free radicals and upregulating the antioxidant systems, such as glutathione (GSH) and superoxide dismutase (SOD), while crossing the blood brain barrier (BBB). These properties have led to significant improvements in the neurologic outcomes of multiple experimental disease models, including cerebral oxidative stress in diabetes mellitus and ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), and epilepsy. Such diseases have mutual biomarkers with ASD, which potentially could be a link to fill the gap of the literature studying the potential of repurposing the SGLT2 inhibitors' use in ameliorating the symptoms of ASD. This review will look at the impact of the SGLT2 inhibitors on neurodevelopmental disorders on the various models, including humans, rats, and mice, with a focus on the SGLT2 inhibitor canagliflozin. Furthermore, this review will discuss how SGLT2 inhibitors regulate the ASD biomarkers, based on the clinical evidence supporting their functions as antioxidant and anti-inflammatory agents capable of crossing the blood-brain barrier (BBB).

Cardiovascular protection by SGLT2 inhibitors - Do anti-inflammatory mechanisms play a role?

BACKGROUND

Metabolic syndrome and related metabolic disturbances represent a state of low-grade inflammation, which accelerates insulin resistance, type 2 diabetes (T2D) and cardiovascular disease (CVD) progression. Among antidiabetic medications, sodium glucose co-transporter (SGLT) 2 inhibitors are the only agents which showed remarkable reductions in heart failure (HF) hospitalizations and major cardiovascular endpoints (MACE) as well as renal endpoints regardless of diabetes status in large randomized clinical outcome trials (RCTs). Although the exact mechanisms underlying these benefits are yet to be established, growing evidence suggests that modulating inflammation by SGLT2 inhibitors may play a key role.

SCOPE OF REVIEW

In this manuscript, we summarize the current knowledge on anti-inflammatory effects of SGLT2 inhibitors as one of the mechanisms potentially mediating their cardiovascular (CV) benefits. We introduce the different metabolic and systemic actions mediated by these agents which could mitigate inflammation, and further present the signalling pathways potentially responsible for their proposed direct anti-inflammatory effects. We also discuss controversies surrounding some of these mechanisms.

MAJOR CONCLUSIONS

SGLT2 inhibitors are promising anti-inflammatory agents by acting either indirectly via improving metabolism and reducing stress conditions or via direct modulation of inflammatory signalling pathways. These effects were achieved, to a great extent, in a glucose-independent manner which established their clinical use in HF patients with and without diabetes.

Anti-inflammatory role of SGLT2 inhibitors as part of their anti-atherosclerotic activity: Data from basic science and clinical trials

Atherosclerosis is a progressive inflammatory disease leading to mortality and morbidity in the civilized world. Atherosclerosis manifests as an accumulation of plaques in the intimal layer of the arterial wall that, by its subsequent erosion or rupture, triggers cardiovascular diseases. Diabetes mellitus is a well-known risk factor for atherosclerosis. Indeed, Type 2 diabetes mellitus patients have an increased risk of atherosclerosis and its associated-cardiovascular complications than non-diabetic patients. Sodium-glucose co-transport 2 inhibitors (SGLT2i), a novel anti-diabetic drugs, have a surprising advantage in cardiovascular effects, such as reducing cardiovascular death in a patient with or without diabetes. Numerous studies have shown that atherosclerosis is due to a significant inflammatory burden and that SGLT2i may play a role in inflammation. In fact, several experiment results have demonstrated that SGLT2i, with suppression of inflammatory mechanism, slows the progression of atherosclerosis. Therefore, SGLT2i may have a double benefit in terms of glycemic control and control of the atherosclerotic process at a myocardial and vascular level. This review elaborates on the anti-inflammatory effects of sodium-glucose co-transporter 2 inhibitors on atherosclerosis.

Esaxerenone, a selective mineralocorticoid receptor blocker, improves insulin sensitivity in mice consuming high-fat diet

BACKGROUND

Esaxerenone is a novel, non-steroidal selective mineralocorticoid receptor (MR) blocker. MR activation plays a crucial role in the development of cardiovascular and metabolic diseases. In this study, we investigated the effects of esaxerenone on various metabolic parameters in mice.

MATERIALS AND METHODS

Esaxerenone (3 mg/kg/day) was orally administered to high-fat diet (HFD)-fed male C57BL/6 mice. Mice fed a normal diet (ND) served as controls. Glucose and insulin tolerance, plasma lipid levels, and transaminase levels were assessed as metabolic parameters. Macrophage accumulation in the adipose tissue was evaluated using histological analysis. 3T3-L1 adipocytes, HepG2 cells, and C2C12 myotubes were used for in vitro experiments. Gene expression and insulin signaling were examined using quantitative RT-PCR and western blotting, respectively.

RESULTS

HFD successfully induced insulin resistance compared with that in ND. Esaxerenone ameliorated insulin resistance (P < 0.05) without altering other metabolic parameters, such as the lipid profile. Esaxerenone administration tended to decrease plasma transaminase levels compared with those in the non-treated group. In the adipose tissue, esaxerenone decreased macrophage accumulation (P < 0.05) and increased the expression levels of adiponectin and PPARγ. Aldosterone significantly decreased the expression levels of PPARγ and adiponectin in 3T3-L1 adipocytes. Furthermore, aldosterone attenuated insulin-induced Akt phosphorylation in 3T3-L1 adipocytes, HepG2 cells, and C2C12 myotubes in a dose-dependent manner (P < 0.01). These effects were ameliorated by pretreatment with esaxerenone.

CONCLUSION

Esaxerenone ameliorated insulin resistance in HFD-fed mice. Reduction of inflammation and improvement in insulin signaling may underlie the beneficial effects of esaxerenone.

SGLT1/2 as the potential biomarkers of renal damage under Apoe−/− and chronic stress via the BP neural network model and support vector machine

Background

Chronic stress (CS) could produce negative emotions. The molecular mechanism of SGLT1 and SGLT2 in kidney injury caused by chronic stress combined with atherosclerosis remains unclear.

Methods

In total, 60 C57BL/6J mice were randomly divided into four groups, namely, control (CON, n = 15), control diet + chronic stress (CON+CS, n = 15), high-fat diet + Apoe−/− (HF + Apoe−/−, n = 15), and high-fat diet + Apoe−/− + chronic stress (HF+Apoe−/− + CS, n = 15) groups. The elevated plus maze and open field tests were performed to examine the effect of chronic stress. The expression of SGLT1 and SGLT2 in the kidney was detected. The support vector machine (SVM) and back propagation (BP) neural network model were constructed to explore the predictive value of the expression of SGLT1/2 on the renal pathological changes. The receiver operating characteristic (ROC) curve analysis was used.

Results

A chronic stress model and atherosclerosis model were constructed successfully. Edema, broken reticular fiber, and increased glycogen in the kidney would be obvious in the HF + Apoe−/− + CS group. Compared with the CON group, the expression of SGLT1/2 in the kidney was upregulated in the HF + Apoe−/− + CS group (P &lt; 0.05). There existed positive correlations among edema, glycogen, reticular fiber, expression of SGLT1/2 in the kidney. There were higher sensitivity and specificity of diagnosis of SGLT1/2 for edema, reticular fiber, and glycogen in the kidney. The result of the SVM and BP neural network model showed better predictive values of SGLT1 and SGLT2 for edema and glycogen in the kidney.

Conclusion

In conclusion, SGLT1/2 might be potential biomarkers of renal damage under Apoe−/− and chronic stress, which provided a potential research direction for future related explorations into this mechanism.

The sodium-glucose co-transporter 2 inhibitor tofogliflozin suppresses atherosclerosis through glucose lowering in ApoE-deficient mice with streptozotocin-induced diabetes

Epidemiological and animal studies have revealed that sodium‐glucose cotransporter 2 (SGLT2) inhibitors suppress cardiovascular events in subjects with type 2 diabetes and atherosclerosis in animal models of diabetes. However, it still remains unclear if the anti‐atherosclerotic effect of SGLT2 inhibitors is entirely dependent on their glucose‐lowering effect. Tofogliflozin, a highly specific SGLT2 inhibitor, was administrated to apolipoprotein‐E‐deficient (ApoEKO) with streptozotocin (STZ)‐induced diabetes and nondiabetic ApoEKO mice. After 6 weeks, samples were collected to investigate the histological changes and peritoneal macrophage inflammatory cytokine levels. Tofogliflozin suppressed atherosclerosis in the diabetic ApoEKO mice. The atherosclerosis lesion areas and accumulation of macrophages in these areas were reduced by tofogliflozin treatment. The expression levels of interleukin (IL)‐1β and IL‐6 in the peritoneal macrophages were significantly suppressed in the tofogliflozin‐treated diabetic ApoEKO mice. Tofogliflozin treatment failed to inhibit atherosclerosis in the nondiabetic ApoEKO mice. No significant difference in the anti‐atherosclerotic effects of insulin and tofogliflozin was observed between diabetic ApoEKO mice with equivalent degrees of glycemic control achieved with the two treatments. Insulin treatment significantly reduced the IL‐1β and IL‐6 expression levels in the peritoneal macrophages of the diabetic ApoEKO mice. Significant decrease of the LPS‐stimulated IL‐1β concentrations was also observed in the conditioned medium of the peritoneal macrophages collected from insulin‐ and tofogliflozin‐treated diabetic ApoEKO mice. These results suggest that tofogliflozin suppresses atherosclerosis by improving glucose intolerance associated with inhibition of inflammation. Tofogliflozin suppresses atherosclerosis in ApoEKO mice with STZ‐induced diabetes via its glucose‐lowering effect.

Mouse models of atherosclerosis in translational research

Atherosclerotic cardiovascular disease (CVD), the major cause of premature human mortality, is a chronic and progressive metabolic and inflammatory disease in large- and medium-sized arteries. Mouse models are widely used to gain mechanistic insights into the pathogenesis of atherosclerosis and have facilitated the discovery of anti-atherosclerotic drugs. Despite promising preclinical studies, many drug candidates have not translated to clinical use because of the complexity of disease patho-mechanisms including lipid metabolic traits and inflammatory, genetic, and hemodynamic factors. We review the current preclinical utility and translation potential of traditional [apolipoprotein E (APOE)- and low-density lipoprotein (LDL) receptor (LDLR)-deficient mice] and emerging mouse models that include partial carotid ligation and AAV8-Pcsk9-D377Y injection in atherosclerosis research and drug discovery. This article represents an important resource in atherosclerosis research.

Pleiotropic effects of SGLT2 inhibitors and heart failure outcomes

Heart failure (HF) represents a major public health concern with increasing prevalence among aging populations, with multifactorial pathophysiology including inflammation, oxidative stress, endothelial dysfunction, and fibrosis, among others. Lately, the use of sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally destined for the treatment of type 2 diabetes mellitus, have revolutionized the treatment of HF. In this review article, we provide the milestones and the latest mechanistic evidence of SGLT2 inhibition in HF. Owing to the results of experimental studies, several pleiotropic effects of SGLT2 inhibitors have been proposed, including the restoration of autophagy which may be significant in the reversal of the aforementioned HF pathophysiology according to a latest hypotheses. Additional mechanisms consist of the regulation of inflammatory, oxidative, and fibrotic pathways, together with the improvement of endothelial function and reduction of epicardial adipose tissue. Other than their role as antidiabetic agents, a reduction in heart failure hospitalizations has been noted following their use in clinical trials, irrespective of DM status and degree of systolic dysfunction. Upcoming randomized trials are expected to additional clinical and mechanistic evidence regarding the diverse effects of SGLT2 inhibition across the spectrum of heart failure.

Role of Sodium-Glucose Co-Transporter 2 Inhibitors in the Regulation of Inflammatory Processes in Animal Models

Sodium-glucose co-transporter 2 inhibitors, also known as gliflozins, were developed as a novel class of anti-diabetic agents that promote glycosuria through the prevention of glucose reabsorption in the proximal tubule by sodium-glucose co-transporter 2. Beyond the regulation of glucose homeostasis, they resulted as being effective in different clinical trials in patients with heart failure, showing a strong cardio-renal protective effect in diabetic, but also in non-diabetic patients, which highlights the possible existence of other mechanisms through which gliflozins could be exerting their action. So far, different gliflozins have been approved for their therapeutic use in T2DM, heart failure, and diabetic kidney disease in different countries, all of them being diseases that have in common a deregulation of the inflammatory process associated with the pathology, which perpetuates and worsens the disease. This inflammatory deregulation has been observed in many other diseases, which led the scientific community to have a growing interest in the understanding of the biological processes that lead to or control inflammation deregulation in order to be able to identify potential therapeutic targets that could revert this situation and contribute to the amelioration of the disease. In this line, recent studies showed that gliflozins also act as an anti-inflammatory drug, and have been proposed as a useful strategy to treat other diseases linked to inflammation in addition to cardio-renal diseases, such as diabetes, obesity, atherosclerosis, or non-alcoholic fatty liver disease. In this work, we will review recent studies regarding the role of the main sodium-glucose co-transporter 2 inhibitors in the control of inflammation.

Association of Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor Use With Cardiovascular and Renal Outcomes in Type 2 Diabetes Mellitus Patients With Stabilized Acute Myocardial Infarction: A Propensity Score Matching Study

Background

Coronary artery disease (CAD) is one of the leading causes of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM), who are at a greater risk of acute myocardial infarction (AMI) and sudden cardiac death. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been shown to reduce cardiovascular events and mortality in T2DM patients with a risk of cardiovascular disease. This study aimed to investigate the effect of SGLT2 inhibitor use on the adverse cardiovascular and renal outcomes in T2DM patients with AMI.

Methods

A total of 1,268 patients admitted to the Coronary Care Unit due to AMI were retrospectively screened.Patients taking SGLT2 inhibitors before or during the index AMI hospitalization were assigned as group 1. Patients who never received SGLT2 inhibitors were assigned as group 2. Patients in groups 1 and 2 were matched in a 1:2 ratio, and 198 T2DM patients with stabilized AMI were retrospectively enrolled for the final analysis.

Results

With a mean follow-up period of 23.5 ± 15.7 months, 3 (4.5%) patients in group 1 and 22 (16.7%) patients in group 2 experienced rehospitalization for acute coronary syndrome (ACS), while 1 (1.5%) patient in group 1 and 7 (5.3%) patients in group 2 suffered sudden cardiac death. The Kaplan–Meier curves demonstrated that the patients in group 1 had a lower risk of adverse cardiovascular outcomes. According to the multivariate analysis, the baseline estimated glomerular filtration rate (eGFR) (P = 0.008, 95% CI: 0.944–0.991) and the use of SGLT2 inhibitors (P = 0.039, 95% CI: 0.116–0.947) were both independent predictors of adverse cardiovascular outcomes. On the other hand, the use of SGLT2 inhibitors was not associated with adverse renal outcomes.

Conclusion

In T2DM patients with stabilized AMI, the use of SGLT2 inhibitors was associated with a lower risk of adverse cardiovascular outcomes. In addition, the baseline renal function was also an independent predictor of adverse cardiovascular outcomes.

Amelioration of endothelial dysfunction by sodium glucose co-transporter 2 inhibitors: pieces of the puzzle explaining their cardiovascular protection

Sodium glucose co‐transporter 2 inhibitors (SGLT‐2is) improve cardiovascular outcomes in both diabetic and non‐diabetic patients. Preclinical studies suggest that SGLT‐2is directly affect endothelial function in a glucose‐independent manner. The effects of SGLT‐2is include decreased oxidative stress and inflammatory reactions in endothelial cells. Furthermore, SGLT2is restore endothelium‐related vasodilation and regulate angiogenesis. The favourable cardiovascular effects of SGLT‐2is could be mediated via a number of pathways: (1) inhibition of the overactive sodium‐hydrogen exchanger; (2) decreased expression of nicotinamide adenine dinucleotide phosphate oxidases; (3) alleviation of mitochondrial injury; (4) suppression of inflammation‐related signalling pathways (e.g., by affecting NF‐κB); (5) modulation of glycolysis; and (6) recovery of impaired NO bioavailability. This review focuses on the most recent progress and existing gaps in preclinical investigations concerning the direct effects of SGLT‐2is on endothelial dysfunction and the mechanisms underlying such effects.

Cardiac mechanisms of the beneficial effects of SGLT2 inhibitors in heart failure: Evidence for potential off-target effects

Sodium glucose cotransporter 2 inhibitors (SGLT2i) constitute a promising drug treatment for heart failure patients with either preserved or reduced ejection fraction. Whereas SGLT2i were originally developed to target SGLT2 in the kidney to facilitate glucosuria in diabetic patients, it is becoming increasingly clear that these drugs also have important effects outside of the kidney. In this review we summarize the literature on cardiac effects of SGLT2i, focussing on pro-inflammatory and oxidative stress processes, ion transport mechanisms controlling sodium and calcium homeostasis and metabolic/mitochondrial pathways. These mechanisms are particularly important as disturbances in these pathways result in endothelial dysfunction, diastolic dysfunction, cardiac stiffness, and cardiac arrhythmias that together contribute to heart failure. We review the findings that support the concept that SGLT2i directly and beneficially interfere with inflammation, oxidative stress, ionic homeostasis, and metabolism within the cardiac cell. However, given the very low levels of SGLT2 in cardiac cells, the evidence suggests that SGLT2-independent effects of this class of drugs likely occurs via off-target effects in the myocardium. Thus, while there is still much to be understood about the various factors which determine how SGLT2i affect cardiac cells, much of the research clearly demonstrates that direct cardiac effects of these SGLT2i exist, albeit mediated via SGLT2-independent pathways, and these pathways may play a role in explaining the beneficial effects of SGLT2 inhibitors in heart failure.

Dapagliflozin attenuates high glucose-induced endothelial cell apoptosis and inflammation through AMPK/SIRT1 activation

Hyperglycemia is a major cause of pathophysiological processes such as oxidative stress, inflammation, and apoptosis in diabetes. Dapagliflozin (DAPA), a novel hypoglycemic drug, has been shown to have anti-apoptotic, anti-inflammatory, and antioxidant effects in multiple experimental studies. In this study, we investigated the protective effects of DAPA in the hyperglycemic condition to identify associated molecular mechanisms. HUVEC endothelial cells were treated with 40 mM glucose for 72h to establish in vitro high glucose (HG) condition model, and then additional groups co-treated with or without DAPA before glucose treatment. Then, cell viability, reactive oxygen species (ROS), proinflammatory cytokines (IL-6 and TNF-α), apoptosis, and SIRT1 expression were measured. The results showed that DAPA pretreatment resulted in increased cell viability. Additionally, DAPA pretreatment decreased endothelial ROS, IL-6, and TNF-α levels in endothelial cells subjected to HG conditions. Moreover, DAPA pretreatment significantly prevented HG-induced apoptosis and caspase-3 activity in HUVECs. Furthermore, DAPA increased the expression of SIRT1, PGC-1α, and increased the phosphorylation levels of AMPK (p-AMPK) in a set of HG conditions in HUVEC cells. However, the endothelial protective effects of DAPA were abolished when cells were subjected to the SIRT1 inhibitor (EX-527) and AMPK inhibitor (Compound C). These findings suggest that DAPA can abrogate HG-induced endothelial cell dysfunction by AMPK/SIRT1 pathway up-regulation. Therefore, suggesting that the activation of AMPK/SIRT1 axis by DAPA may be a novel target for the treatment of HG-induced endothelial cell injury. This article is protected by copyright. All rights reserved.

Old and Novel Therapeutic Approaches in the Management of Hyperglycemia, an Important Risk Factor for Atherosclerosis

Hyperglycemia is considered one of the main risk factors for atherosclerosis, since high glucose levels trigger multiple pathological processes, such as oxidative stress and hyperproduction of pro-inflammatory mediators, leading to endothelial dysfunction. In this context, recently approved drugs, such as glucagon-like-peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2i), could be considered a powerful tool for to reduce glucose concentration and cardiovascular risk. Interestingly, many patients with type 2 diabetes mellitus (T2DM) and insulin resistance have been found to be deficient in vitamin D. Recent studies pointed out the unfavorable prognostic values of T2DM and vitamin D deficiency in patients with cardiac dysfunction, either when considered individually or together, which shed light on the role of vitamin D in general health status. New evidence suggests that SGLT2i could adversely affect the production of vitamin D, thereby increasing the risk of fractures, which are common in patients with T2DM. Therefore, given the biological effects of vitamin D as an anti-inflammatory mediator and a regulator of endothelial function and calcium equilibrium, these new findings should be taken into consideration as well. The aim of this review is to gather the latest advancements regarding the use of antidiabetic and antiplatelet drugs coupled with vitamin D supplementation to control glucose levels, therefore reducing the risk of coronary artery disease (CAD).

Effects of SGLT2 Inhibitors on Atherosclerosis: Lessons from Cardiovascular Clinical Outcomes in Type 2 Diabetic Patients and Basic Researches

Atherosclerosis-caused cardiovascular diseases (CVD) are the leading cause of mortality in type 2 diabetes mellitus (T2DM). Sodium-glucose cotransporter 2 (SGLT2) inhibitors are effective oral drugs for the treatment of T2DM patients. Multiple pre-clinical and clinical studies have indicated that SGLT2 inhibitors not only reduce blood glucose but also confer benefits with regard to body weight, insulin resistance, lipid profiles and blood pressure. Recently, some cardiovascular outcome trials have demonstrated the safety and cardiovascular benefits of SGLT2 inhibitors beyond glycemic control. The SGLT2 inhibitors empagliflozin, canagliflozin, dapagliflozin and ertugliflozin reduce the rates of major adverse cardiovascular events and of hospitalization for heart failure in T2DM patients regardless of CVD. The potential mechanisms of SGLT2 inhibitors on cardioprotection may be involved in improving the function of vascular endothelial cells, suppressing oxidative stress, inhibiting inflammation and regulating autophagy, which further protect from the progression of atherosclerosis. Here, we summarized the pre-clinical and clinical evidence of SGLT2 inhibitors on cardioprotection and discussed the potential molecular mechanisms of SGLT2 inhibitors in preventing the pathogenesis of atherosclerosis and CVD.

Neuroprotective Effect of SGLT2 Inhibitors

Patients with diabetes are at higher risk of cardiovascular diseases and cognitive impairment. SGLT2 inhibitors (Empagliflozin, Canagliflozin, Dapagliflozin, Ertugliflozin, Sotagliflozin) are newer hypoglycemic agents with many pleiotropic effects. In this review, we discuss their neuroprotective potential. SGLT2 inhibitors (SGLT2i) are lipid-soluble and reach the brain/serum ratio from 0.3 to 0.5. SGLT receptors are present in the central nervous system (CNS). Flozins are not fully SGLT2-selective and have an affinity for the SGLT1 receptor, which is associated with protection against ischemia/reperfusion brain damage. SGLT2i show an anti-inflammatory and anti-atherosclerotic effect, including reduction of proinflammatory cytokines, M2 macrophage polarization, JAK2/STAT1 and NLRP3 inflammasome inhibition, as well as cIMT regression. They also mitigate oxidative stress. SGLT2i improve endothelial function, prevent remodeling and exert a protective effect on the neurovascular unit, blood-brain barrier, pericytes, astrocytes, microglia, and oligodendrocytes. Flozins are also able to inhibit AChE, which contributes to cognitive improvement. Empagliflozin significantly increases the level of cerebral BDNF, which modulates neurotransmission and ensures growth, survival, and plasticity of neurons. Moreover, they may be able to restore the circadian rhythm of mTOR activation, which is quite a novel finding in the field of research on metabolic diseases and cognitive impairment. SGLT2i have a great potential to protect against atherosclerosis and cognitive impairment in patients with type 2 diabetes mellitus.

The Role of SGLT2 Inhibitors in Atherosclerosis: A Narrative Mini-Review

Objective: Sodium glucose cotransporter 2 inhibitors (SGLT2-is) are antidiabetic drugs that improve glycemic control by limiting urinary glucose reuptake in the proximal tubule. SGLT2-is might suppress atherosclerotic processes and ameliorate the prognosis of patients with diabetes mellitus diagnosed with or at high risk of atherosclerotic cardiovascular disease (ASCVD). In this mini review, we examine the role of SGLT2-is in the development and progression of atherosclerosis throughout its spectrum, from subclinical atherosclerosis to ASCVD.

Data Sources—PubMed and Google Scholar were searched for publications related to SGLT2-is and atherosclerosis. All types of articles were considered, including clinical trials, animal studies, in vitro observations, and reviews and meta-analyses. Data were examined according to their impact and clinical relevance.

Synopsis of Content—We first review the underlying mechanisms of SGLT2-is on the development and progression of atherosclerosis, including favorable effects on lipid metabolism, reduction of systemic inflammation, and improvement of endothelial function. We then discuss the putative impact of SGLT2-is on the formation, composition, and stability of atherosclerotic plaque. Furthermore, we evaluate the effects of SGLT2-is in subclinical atherosclerosis assessed by carotid intima media thickness and pulse wave velocity. Subsequently, we summarize the effects of SGLT2-is in ASCVD events, including ischemic stroke, angina pectoris, myocardial infarction, revascularization, and peripheral artery disease, as well as major adverse cardiovascular events, cardiovascular mortality, heart failure, and chronic kidney disease. Moreover, we examine factors that could modify the role of SGLT2-is in atherosclerosis, including sex, age, diabetes, glycemic control, ASCVD, and SGLT2-i compounds. Additionally, we propose future directions that can improve our understanding of SGLT2-is and atherosclerosis.

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 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.

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.