Hyperglycaemic impairment of PAR2-mediated vasodilation: Prevention by inhibition of aortic endothelial sodium-glucose-co-Transporter-2 and minimizing oxidative stress

Empagliflozin Leads to Faster Improvement in Arterial Stiffness Compared to Dapagliflozin: A Double-Blind Clinical

(1) Background: Arterial stiffness, often measured by carotid-femoral pulse wave velocity (cf-PWV), is crucial in cardiovascular disease. Dapagliflozin has shown rapid effects on arterial stiffness, but there is limited evidence of empagliflozin's acute effects, especially in type 2 diabetes (T2D) patients. This study evaluated the acute effects of empagliflozin and dapagliflozin on arterial stiffness and blood pressure (BP). (2) Methods: A one-week double-blind randomized trial involved 30 T2D patients on stable metformin therapy. Participants received empagliflozin (25 mg/day), dapagliflozin (10 mg/day), or a placebo. Arterial stiffness was assessed via cf-PWV, and BP was measured with an automated sphygmomanometer. (3) Results: Both SGLT2 inhibitors significantly reduced cf-PWV compared to the placebo after one week (p < 0.05), with dapagliflozin showing a more pronounced effect. No significant differences were observed in BP changes. (4) Conclusion: Short-term treatment with SGLT2 inhibitors acutely reduces arterial stiffness in T2D patients, with empagliflozin demonstrating a stronger effect, supporting the potential vascular benefits of SGLT2 inhibitors beyond glucose control.

Sodium-Glucose Cotransporter 2 Inhibitors in Aortic Stenosis: Toward a Comprehensive Cardiometabolic Approach

Aortic stenosis (AS), the most prevalent valvular heart disease, is increasingly recognized as an active disease process driven by a convergence of hemodynamic stress, inflammation, oxidative injury, and metabolic remodeling. While transcatheter and surgical valve replacement remain the standard interventions for severe AS, they fail to reverse the chronic myocardial remodeling that underlies adverse outcomes in many patients. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have emerged as promising cardioprotective agents, with effects extending well beyond glycemic control. Recent mechanistic studies reveal that SGLT2 is expressed in the myocardium of patients with AS and is linked to pathways of fibrosis, inflammation, and energetic dysfunction. Experimental models and translational data demonstrate that SGLT2 inhibition attenuates maladaptive remodeling through modulation of TGF-β, NF-κB, NLRP3 inflammasome, and oxidative stress signaling while enhancing mitochondrial energetics and endothelial function. Importantly, clinical evidence from randomized and real-world studies suggests that SGLT2 inhibitors improve heart failure outcomes following valve replacement and may slow AS progression. This review integrates current pathophysiological insights with emerging molecular and clinical data to delineate the therapeutic rationale for SGLT2 inhibition in AS. By targeting both myocardial and valvular components of the disease, SGLT2 inhibitors may offer a novel disease-modifying strategy with potential implications across the AS continuum-from asymptomatic stages to the post-interventional setting. Ongoing and future trials are warranted to define optimal patient selection, timing, and biomarkers for response to SGLT2 inhibitor therapy in this increasingly high-risk population.

Canagliflozin-driven cellular re-differentiation and migration inhibition in vascular smooth muscle cells via PTEN upregulation

The phenotypic modulation of vascular smooth muscle cells (VSMCs) is a key factor in the development and progression of atherosclerosis. Canagliflozin, a sodium-glucose cotransporter 2 inhibitor, has shown efficacy in reducing atherosclerotic lesions; however, its specific effects on VSMC phenotype expression and the underlying intracellular signaling remain poorly understood. This study utilized VSMCs from rat aortic explants to evaluate the impact of canagliflozin on cell outgrowth, migration, cellular morphology, expression of phenotypic markers, and intracellular signaling. Canagliflozin significantly inhibited VSMC outgrowth and migration in a dose-dependent manner. Additionally, it induced an elongated VSMC morphology consistent with a contractile phenotype, while increasing the expression of contractile markers such as myocardin and calponin and reducing the expression of synthetic markers, including collagen I and III. Western blot study revealed that canagliflozin upregulated PTEN expression and suppressed AKT activation, both critical regulators of VSMC phenotype. Notably, PTEN knockdown via RNA interference reversed the inhibitory effects of canagliflozin on VSMC migration and phenotype switching, underscoring the central role of PTEN in these processes. These findings suggest that canagliflozin promotes a contractile phenotype in VSMCs by modulating the expression of phenotypic markers, upregulating PTEN, and downregulating AKT activation, thereby potentially inhibiting VSMC migration.

Exploring the effect of dapagliflozin on coronary inflammation in type 2 diabetes patients based on the coronary artery perivascular fat attenuation index

BACKGROUND

The pericoronary fat attenuation index (FAI) is a novel biomarker that serves as an indicator of coronary artery inflammation. Dapagliflozin has become an important component of standard treatment for type 2 diabetes because of its cardioprotective and renoprotective effects. The objective of this research was to explore how dapagliflozin impacts coronary artery inflammation in T2DM patients and to establish a novel theoretical framework for the protective role of dapagliflozin in the cardiovascular system.

METHODS

This research retrospectively included 271 T2DM patients treated with coronary computed tomography angiography (CCTA) at Hebei Provincial People's Hospital from January 2021 to November 2024, with 103 patients receiving dapagliflozin therapy (dapagliflozin+) and 168 patients not receiving dapagliflozin (dapagliflozin-) (oral dapagliflozin 10 mg/day for no less than 6 months). Baseline clinical information, laboratory markers, and CCTA-related metrics were collected and analysed across both groups. The relationship between dapagliflozin treatment and the pericoronary FAI was analysed using multiple linear regression to control for confounding variables, and the correlation between the two variables was further examined across various subgroups.

RESULTS

Compared with those in the dapagliflozin- group, the patients in the dapagliflozin+ group were younger (P<0.001), and the proportion of men was higher (P<0.05). There were no between-group differences in the baseline data, such as diabetes course, BMI, and blood lipid status (P>0.05). The FAI of the LAD and RCA in the dapagliflozin+ group was lower than that in the other groups, and the average FAI of the three coronary arteries was also significantly lower, while there was no significant difference in the LCX (LAD: dapagliflozin- group: -85.50 (-90.43, -78.27)，dapagliflozin+ group：-86.94 (-92.81, -81.57)，P= 0.044；RCA：dapagliflozin- group：-86.31 (-92.12, -80.09), dapagliflozin+ group：-88.79 (-94.59, -83.31), P= 0.019; Mean: dapagliflozin- group: -84.05 (-87.73, -77.45), dapagliflozin+ group: -84.88 (-89.82, -79.67), P= 0.022; LCX: dapagliflozin- group：-77.81 (-82.57, -71.75), dapagliflozin+ group: -78.25 (-84.56, -72.15), P = 0.260). Multiple linear regression analyses revealed an independent association between dapagliflozin treatment and a decreased in FAI in the LAD and RCA (LAD: β=-2.449; RCA: β=-3.897; P values are all less than 0.05). This association was different across various subsets of T2DM patients.

CONCLUSION

Dapagliflozin treatment is associated with a significant reduction in coronary artery inflammation in T2DM patients, which may partly explain its beneficial effects on reducing cardiovascular risk.

Sodium-glucose co-transporter inhibitors for APOL1 kidney disease: A call for studies

Renal risk variants in the apolipoprotein L1 (APOL1) gene confer protection against trypanosomiasis, but these risk variants (G1 and G2 variants) also predispose to kidney disease among individuals, especially from Sub-SaharanAfrica. Currently, the mechanisms of how these renal risk variants induce kidney damage are not precisely defined, but lysosomal and mitochondrial dysfunction, altered ion channel activity, altered autophagy, and disordered immunity are suggested. Currently, there is no specific treatment for APOL1 kidney disease (APOL1-KD) although several potential disease-specific therapeutic agents are being evaluated in clinical trials. Non-specific interventions include proteinuria screening, salt restriction, and renin-angiotensin-aldosterone system inhibition but are not sufficient to prevent kidney disease progression in APOL1-KD. Given the lack of specific treatment options, more efforts are necessary to reduce kidney disease progression. Sodium glucose co-transport-2 (SGLT2) inhibitors (SGLT2i) are gaining attention for benefits in proteinuric kidney diseases and exert many beneficial effects which theoretically may be beneficial in the context of APOL1-KD. These beneficial effects include but are not limited to increased natriuresis, decreased proteinuria/albuminuria, and mitochondrial dysfunction. SGLT2i have antioxidant, anti-inflammatory and anti-fibrotic effects. In the current review, we highlight the potential reasons for exploring the use of SGLT2i in APOL1-KD. Future studies are warranted to explore if SGLT2i use can provide protection in APOL1-KD.

The protective role of SGLT2 inhibitors on aortic aneurysm mediated by oxidative stress and inflammation in type 2 diabetes mellitus

BACKGROUND

Sodium-glucose transport protein 2 inhibitors (SGLT2i) have been widely used to treat patients with type 2 diabetes mellitus (T2DM) and have demonstrated protective effects against certain cardiovascular diseases. However, no clinical research has been conducted to explore the relationship between SGLT2i and the risk of aortic aneurysm (AA).

METHODS

We extracted and analyzed the data of 4964 patients with T2DM from the First Affiliated Hospital of Zhengzhou University during July 2017 to January 2023. Multivariate Cox models, interaction analysis and Kaplan-Meier curves were performed to approximate the associations of SGLT2i therapy on the risk of AA. A sensitivity analysis was performed to test the robustness of results. Mediation analyses explored the roles of inflammatory (neutrophils, lymphocytes, C-reactive protein and alkaline phosphatase) and oxidative stress (gamma glutamyl transferase, total bilirubin, and uric acid) markers in the associations between SGLT2i and AA.

RESULTS

A total of 1942 SGLT2 inhibitor (SGLT2i) users (39.12%) and 3022 non-SGLT2 inhibitor (NonSGLT2i) users were included in final analysis. After full adjustment for potential risk factors, SGLT2i patients were associated with a lower risk of aortic aneurysm (HR, 95% CI 0.91, 0.89-0.98, p = 0.001). Dapagliflozin showed the greatest difference for reduction of aortic aneurysm incidence (HR, 95% CI 0.84, 0.80-0.95, p = 0.011). Subgroup analysis indicated that use of SGLT2i lower the risk of aortic aneurysm in some subgroups of T2DM patients. The sensitivity analysis demonstrated the robustness of the results. CRP, lymphocytes, neutrophils, and uric acid were significantly associated with both SGLT2i and AA, with mediation proportions of 13.35%, 8.83%, 9.67% and 31.17%, respectively.

CONCLUSIONS

Our study suggested that patients using SGLT2i may have a lower risk of aortic aneurysm, and this effect could potentially be mediated by inflammation and oxidative stress. Further mechanistic and prospective studies are required to verify this association.

Polynorepinephrine nanoparticles activate vascular smooth muscle alpha-1 adrenergic receptors

Biocompatible polymeric nanoparticles (NPs) as carriers for therapeutic agents with multifunctional activities have received unprecedented attention for a variety of bio-pharmaceutical applications. We describe the synthesis, the fluorescence properties, the bio-compatible nature and the alpha-1 adrenergic receptor bio-activity of engineered quantum dot-like polynorepinephrine (PNE) NPs. The spherical PNE NPs, which are internalized in smooth muscle cells via a receptor-selective mechanism, activate alpha-1-adrenoceptors in intact mouse aorta and aorta-derived cultured smooth muscle cells, leading to the activation of calcium signaling/contraction and stimulation of mitogen-activated protein kinase (MAPK), thereby displaying receptor-triggering biological activity, possibly acting both extracellularly and intracellularly. Our data indicate that NPs generated by the polymerization of pharmacologically active compounds like norepinephrine can retain receptor-selective biological activity coupled to inherent fluorescence.

Impact of sodium-glucose cotransporter-2 inhibitors on pulmonary vascular cell function and arterial remodeling

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors represent a cutting-edge class of oral antidiabetic therapeutics that operate through selective inhibition of glucose reabsorption in proximal renal tubules, consequently augmenting urinary glucose excretion and attenuating blood glucose levels. Extensive clinical investigations have demonstrated their profound cardiovascular efficacy. Parallel basic science research has elucidated the mechanistic pathways through which diverse SGLT-2 inhibitors beneficially modulate pulmonary vascular cells and arterial remodeling. Specifically, these inhibitors exhibit promising potential in enhancing pulmonary vascular endothelial cell function, suppressing pulmonary smooth muscle cell proliferation and migration, reversing pulmonary arterial remodeling, and maintaining hemodynamic equilibrium. This comprehensive review synthesizes current literature to delineate the mechanisms by which SGLT-2 inhibitors enhance pulmonary vascular cell function and reverse pulmonary remodeling, thereby offering novel therapeutic perspectives for pulmonary vascular diseases.

Progress of SGLT2 inhibitors in the treatment of common immune-related nephropathies

The immune system can lead to a variety of renal diseases through direct or indirect mechanisms. In immune-mediated nephropathy, though standardized treatment, there are still a small number of patients with further decline in renal function, which may even progress to renal failure; sodium-glucose cotransporter protein 2 (SLC5A2,SGLT2) inhibitors not only can significantly reduce blood glucose, but also have an additional protective effect on the kidneys and the heart; this review concludes the potential mechanism of the renal protective effect of SGLT2i and the new advances in the recent years in common immune-mediated nephropathies, which can provide new theoretical references to optimize the therapeutic strategy of common immune-mediated nephropathies.

Synthesis of potent vasodilating agents: in silico and in vitro evaluation of 6-(4-substitutedphenyl)-3-pyridazinone derivatives as potential hydralazine analogues

People of all age categories and lifestyles suffer to different extents from hypertension. Accordingly, this necessitates the rise of new ways to defeat this enemy. Vasodilators exert a principal portion of highly effectual antihypertensive agents; our research is focused on the design, synthesis and biological evaluation of a new series of 6-(4-substitutedphenyl)-3-pyridazinones as potential hydralazine vasodilator analogues implementing both in vitro and in silico approaches. All the synthesized compounds were assessed for their vitro vasorelaxant activity against multiple references. New members revealed potent vasorelaxant activity (EC50 = 0.02916-1.907 µM) compared to the conventional vasorelaxants hydralazine, diazoxide, isosorbitole mononitrate and nitroglycerin (EC50 = 18.21, 19.5, 30.1 and 0.1824 µM, respectively). Compounds 2e, 2h and 2j exerted superior activities compared to others with EC50 = 0.1162, 0.07154 and 0.02916 µM, respectively. The physiochemical properties and drug-likeliness behavior of the new derivatives were investigated by conducting ADMET studies.

The Potential Impact of SGLT2-I in Diabetic Foot Prevention: Promising Pathophysiologic Implications, State of the Art, and Future Perspectives-A Narrative Review

The impact of diabetic foot (DF) on the healthcare system represents a major public health problem, leading to a considerable clinical and economic burden. The factors contributing to DF's development and progression are strongly interconnected, including metabolic causes, neuropathy, arteriopathy, and inflammatory changes. Sodium-glucose cotransporter 2 inhibitors (SGLT2-i), novel oral hypoglycemic drugs used as an adjunct to standard treatment, have recently changed the pharmacological management of diabetes. Nevertheless, data about the risk of limb amputation, discordant and limited to canagliflozin, which is currently avoided in the case of peripheral artery disease, have potentially discouraged the design of specific studies targeting DF. There is good evidence for the single immunomodulatory, neuroprotective, and beneficial vascular effects of SGLT2-i. Still, there is no clinical evidence about the early use of SGLT2-i in diabetic foot due to the lack of longitudinal and prospective studies proving the effect of these drugs without confounders. This narrative review aims to discuss the main evidence about the impact of SGLT2-i on the three complications of diabetes implicated in the development of DF, the state of the art, and the potential future implications.

Deciphering the role of endothelial granulocyte macrophage-CSF in chronic inflammation associated with HIV

People with HIV (PWH) experience endothelial dysfunction (ED) that is aggravated by chronic inflammation and microbial translocation across a damaged gut barrier. Although this paradigm is well-described, downstream pathways that terminate in endothelial dysfunction are only partially understood. This study found increased expression of granulocyte macrophage colony stimulating factor (GM-CSF), toll-like receptor-4 (TLR4), and myeloperoxidase in the aortic endothelium of PWH compared to those without HIV. Bacteria-derived lipopolysaccharide (LPS) heightened glucose uptake and induced GM-CSF expression in primary human endothelial cells. Exposure to sodium-glucose cotransporter-2 (SGLT2) inhibitors reduced glucose uptake, GM-CSF release, and ED in LPS-activated endothelial cells ex vivo, and PWH treated with SGLT2 inhibitors for diabetes had significantly lower plasma GM-CSF levels than non-diabetic PWH not on this medication. The findings suggest that microbial products trigger glucose uptake and GM-CSF expression in the endothelium, contributing to localized inflammation in PWH. Modifying this altered state could offer therapeutic benefits.

Empagliflozin and Dapagliflozin Improve Endothelial Function in Mexican Patients with Type 2 Diabetes Mellitus: A Double-Blind Clinical Trial

AIM

To assess the acute effect of empagliflozin versus dapagliflozin administration on flow-mediated vasodilation in patients with type 2 diabetes mellitus.

DESIGN

A double-blind clinical trial, at the Experimental and Clinical Therapeutics Institute, University Health Sciences Center, at the Universidad de Guadalajara, in inpatients with T2D according to the 2023 ADA criteria.

METHODS

Thirty patients (15 males and 15 females), aged between 35 and 65 years, were included in this study, according to the 2023 ADA criteria. The eligible patients were randomly assigned to three groups: empagliflozin 25 mg once daily, dapagliflozin 10 mg once daily, or placebo once daily. Anthropometric parameters were taken using validated techniques. FMD was measured using a high-resolution semiautomatic ultrasound UNEX-EF 38G (UNEX Co., Ltd., Nagoya, Japan). Arterial tension was determined with the OMRON electronic digital sphygmomanometer (HEM 907 XL, Kyoto, Japan).

RESULTS

The group of patients who received empagliflozin had a significantly lower baseline flow-mediated dilation (FMD) compared to the group receiving dapagliflozin (p = 0.017); at the end of this study, the empagliflozin group achieved a comparable FMD to the dapagliflozin group (p = 0.88).

CONCLUSION

After the treatment period, the empagliflozin and dapagliflozin groups achieved similar FMD, suggesting a class effect.

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.

Empagliflozin ameliorates vascular calcification in diabetic mice through inhibiting Bhlhe40-dependent NLRP3 inflammasome activation

Type 2 diabetes mellitus (T2DM) patients exhibit greater susceptibility to vascular calcification (VC), which has a higher risk of death and disability. However, there is no specific drug for VC therapy. NLRP3 inflammasome activation as a hallmark event of medial calcification leads to arterial stiffness, causing vasoconstrictive dysfunction in T2DM. Empagliflozin (EMPA), a sodium-glucose co-transporter 2 inhibitor (SGLT2i), restrains hyperglycemia with definite cardiovascular benefits. Given the anti-inflammatory activity of EMPA, herein we investigated whether EMPA protected against VC in the aorta of T2DM mice by inhibiting NLRP3 inflammasome activation. Since db/db mice receiving a normal diet developed VC at the age of about 20 weeks, we administered EMPA (5, 10, 20 mg·kg-1·d-1, i.g) to 8 week-old db/db mice for 12 weeks. We showed that EMPA intervention dose-dependently ameliorated the calcium deposition, accompanied by reduced expression of RUNX2 and BMP2 proteins in the aortas. We found that EMPA (10 mg·kg-1·d-1 for 6 weeks) also protected against VC in vitamin D3-overloaded mice, suggesting the protective effects independent of metabolism. We showed that EMPA (10 mg·kg-1·d-1) inhibited the abnormal activation of NLRP3 inflammasome in aortic smooth muscle layer of db/db mice. Knockout (KO) of NLRP3 significantly alleviated VC in STZ-induced diabetic mice. The protective effects of EMPA were verified in high glucose (HG)-treated mouse aortic smooth muscle cells (MOVASs). In HG-treated NLRP3 KO MOVASs, EMPA (1 μM) did not cause further improvement. Bioinformatics and Western blot analysis revealed that EMPA significantly increased the expression levels of basic helix-loop-helix family transcription factor e40 (Bhlhe40) in HG-treated MOVASs, which served as a negative transcription factor directly binding to the promotor of Nlrp3. We conclude that EMPA ameliorates VC by inhibiting Bhlhe40-dpendent NLRP3 inflammasome activation. These results might provide potential significance for EMPA in VC therapy of T2DM patients.

Tofogliflozin Delays Portal Hypertension and Hepatic Fibrosis by Inhibiting Sinusoidal Capillarization in Cirrhotic Rats

BACKGROUND

Liver cirrhosis leads to portal hypertension (PH) with capillarization of liver sinusoidal endothelial cells (LSECs), although drug treatment options for PH are currently limited. Sodium glucose transporter 2 inhibitors, which are antidiabetic agents, have been shown to improve endothelial dysfunction. We aimed to elucidate the effect of tofogliflozin on PH and liver fibrosis in a rat cirrhosis model.

METHODS

Male-F344/NSlc rats repeatedly received carbon tetrachloride (CCl4) intraperitoneally to induce PH and liver cirrhosis alongside tofogliflozin (10 or 20 mg/kg). Portal hemodynamics and hepatic phenotypes were assessed after 14 weeks. An in vitro study investigated the effects of tofogliflozin on the crosstalk between LSEC and activated hepatic stellate cells (Ac-HSC), which are relevant to PH development.

RESULTS

Tofogliflozin prevented PH with attenuated intrahepatic vasoconstriction, sinusoidal capillarization, and remodeling independent of glycemic status in CCl4-treated rats. Hepatic macrophage infiltration, proinflammatory response, and fibrogenesis were suppressed by treatment with tofogliflozin. In vitro assays showed that tofogliflozin suppressed Ac-HSC-stimulated capillarization and vasoconstriction in LSECs by enhancing the antioxidant capacity, as well as inhibited the capilliarized LSEC-stimulated contractive, profibrogenic, and proliferative activities of Ac-HSCs.

CONCLUSIONS

Our study provides strong support for tofogliflozin in the prevention of liver cirrhosis-related PH.

Cardiovascular benefits of SGLT2 inhibitors and GLP-1 receptor agonists through effects on mitochondrial function and oxidative stress

Overloaded glucose levels in several metabolic diseases such as type 2 diabetes (T2D) can lead to mitochondrial dysfunction and enhanced production of reactive oxygen species (ROS). Oxidative stress and altered mitochondrial homeostasis, particularly in the cardiovascular system, contribute to the development of chronic comorbidities of diabetes. Diabetes-associated hyperglycemia and dyslipidemia can directly damage vascular vessels and lead to coronary artery disease or stroke, and indirectly damage other organs and lead to kidney dysfunction, known as diabetic nephropathy. The new diabetes treatments include Na+-glucose cotransporter 2 inhibitors (iSGLT2) and glucagon-like 1 peptide receptor agonists (GLP-1RA), among others. The iSGLT2 are oral anti-diabetic drugs, whereas GLP-1RA are preferably administered through subcutaneous injection, even though GLP-1RA oral formulations have recently become available. Both therapies are known to improve both carbohydrate and lipid metabolism, as well as to improve cardiovascular and cardiorenal outcomes in diabetic patients. In this review, we present an overview of current knowledge on the relationship between oxidative stress, mitochondrial dysfunction, and cardiovascular therapeutic benefits of iSGLT2 and GLP-1RA. We explore the benefits, limits and common features of the treatments and remark how both are an interesting target in the prevention of obesity, T2D and cardiovascular diseases, and emphasize the lack of a complete understanding of the underlying mechanism of action.

The effect of sodium-glucose co-transporter-2 inhibitors on markers of subclinical atherosclerosis

BACKGROUND

Despite the widespread use of classical cholesterol-lowering drugs to mitigate the adverse impacts of dyslipidaemia on atherosclerosis, many patients still face a substantial residual risk of developing atherosclerotic cardiovascular disease (CVD). This risk is partially attributed to non-traditional pathophysiological pathways. Latest evidence suggests that sodium glucose co-transporter-2 (SGLT2) inhibitors are beneficial for patients suffering from type 2 diabetes mellitus (T2DM) or established CVD by reducing morbidity and mortality. However, the underlying mechanisms of this benefit have not been clearly elucidated. It has been hypothesized that one possible mechanism could be the attenuation of subclinical atherosclerosis (SA) progression.

AIM

The objective of this narrative review is to examine the present evidence concerning the impact of SGLT2 inhibitors on markers of SA.

RESULTS

The current evidence on the efficacy of SGLT2 on SA, endothelial function and arterial stiffness remains controversial. Findings from observational and randomized studies are quite heterogeneous; however, they converge that the antiatherosclerotic activity of SGLT2 inhibitors is not strong enough to be widely used for prevention of atherosclerosis progression in patients with or without T2DM.

CONCLUSIONS

Further research is needed to investigate the underlying mechanisms and the possible beneficial impact of SGLT2i on primary and secondary CVD prevention through attenuation of premature atherosclerosis progression.

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.

Impact of Sodium-Glucose Cotransporter 2 Inhibitor on Recurrence After Catheter Ablation for Atrial Fibrillation in Patients With Diabetes: A Propensity-Score Matching Study and Meta-Analysis

BACKGROUND

The association between sodium-glucose cotransporter 2 inhibitors (SGLT2i) and atrial fibrillation (AF) recurrence after catheter ablation among patients with diabetes and AF remains unclear.

METHODS AND RESULTS

Patients with AF undergoing initial catheter ablation with a history of diabetes from the China AF registry were included. Patients using SGLT2i were identified and matched by propensity score with non-SGLT2i patients in a 1:3 ratio. The main outcome was AF recurrence during the 18-month follow-up. A total of 138 patients with diabetes with SGLT2i therapy and 387 without SGLT2i were analyzed. AF recurrence occurred in 37 patients (26.8%) in the SGLT2i group and 152 patients (39.3%) in the non-SGLT2i group during a total of 593.3 person-years follow-up. The SGLT2i group was associated with lower AF recurrence compared with the non-SGLT2i group (hazard ratio, 0.63 [95% CI, 0.44-0.90], P=0.007). A total of 4 studies were analyzed in our meta-analysis demonstrating that SGLT2i was associated with lower AF recurrence after catheter ablation (odds ratio, 0.61 [95% CI, 0.54-0.69]; P<0.001, I2=0.0%).

CONCLUSIONS

Our prospective study coupled with a meta-analysis demonstrated a lower risk of AF recurrence with the use of SGLT2i among patients with diabetes after AF ablation.

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.

Protective effect of canagliflozin on post-resuscitation myocardial function in a rat model of cardiac arrest

BACKGROUND

Currently, most patients with cardiac arrest (CA) show reversible myocardial dysfunction, hemodynamic instability, systemic inflammation and other pathophysiological state in early stage of resuscitation, some patients may eventually progress to multiple organ failure. There is evidence that heart failure is the terminal stage in the development of various cardiovascular diseases. Although the cardio-protective effect of canagliflozin (CANA) has been confirmed in large clinical studies and recommended in domestic and international heart failure-related guidelines, the effectiveness of CANA after resuscitation remains unclear. In this study, we constructed a modified CA/CPR rat model to investigate whether CANA administered on post-resuscitation improves myocardial function.

METHODS

Twenty-fourth healthy male Sprague-Dawley rats were randomized into four groups: (1) Sham + placebo group, (2) Sham + CANA group, (3) CPR + placebo group, and (4) CPR + CANA group. Ventricular fibrillation was induced by transcutaneous electrical stimulation on epicardium. After 6 min untreated ventricular fibrillation, chest compressions was initiated. The rats were received an injection of placebo or canagliflozin (3 ug/kg) randomly 15 min after restore of spontaneous circulation (ROSC). Electrocardiogram (ECG) and blood pressure were continuously detected in each group throughout the experiment. The rats were killed 6 h after ROSC to collected the arterial serum and myocardial tissue. Myocardial injury was estimated with concentrations of inflammatory factors, oxidative stress indexes and, apoptosis index, myocardial injury markers, echocardiography and myocardial pathological slices.

RESULTS

After resuscitation, mean arterial pressure (MAP) were significantly increased after cardiopulmonary resuscitation in CANA group rats when compared with placebo group. Heart rate, body lactate returned and left ventricular ejection fraction (LVEF) to normal levels in a shorter time and the myocardial injury was obviously attenuated in CPR + CANA group. Inflammatory factors (IL-6, TNF-α) and oxidative stress indexes (MAD, SOD, CAT) were dramatically decreased with the administration of CANA. The expression of apoptosis index (BAX, caspase-3) were higher in CPR + placebo group and the expression of anti-apoptosis index (Bcl-2) was lower (P < 0.05).

CONCLUSIONS

The administration of CANA effectively reduces myocardial ischaemia/reperfusion (I/R) injury after cardiac arrest and cardiopulmonary resuscitation (CPR), and the underlying mechanism may be related to anti-inflammation, oxidative stress and apoptosis.

SGLT2 Inhibitors in Aging-Related Cardiovascular Disease: A Review of Potential Mechanisms

Population aging combined with higher susceptibility to cardiovascular diseases in older adults is increasing the incidence of conditions such as atherosclerosis, myocardial infarction, heart failure, myocardial hypertrophy, myocardial fibrosis, arrhythmia, and hypertension. sodium-glucose cotransporter 2 inhibitors (SGLT2i) were originally developed as a novel oral drug for patients with type 2 diabetes mellitus. Unexpectedly, recent studies have shown that, beyond their effect on hyperglycemia, SGLT2i also have a variety of beneficial effects on cardiovascular disease. Experimental models of cardiovascular disease have shown that SGLT2i ameliorate the process of aging-related cardiovascular disease by inhibiting inflammation, reducing oxidative stress, and reversing endothelial dysfunction. In this review, we discuss the role of SGLT2i in aging-related cardiovascular disease and propose the use of SGLT2i to prevent and treat these conditions in older adults.

Role of canagliflozin in ameliorating isoprenaline induced cardiomyocyte oxidative stress via the heme oxygenase-1 mediated pathway

Canagliflozin (CZ) is commonly prescribed for management of type-2 diabetes mellitus (T2DM); it also can reduce the risk of myocardial infarction. We used 80 albino Wistar rats to investigate the cardioprotective potential of CZ against oxidative stress caused by administration of isoprenaline (ISO). We found that ISO stimulates production of reactive oxygen species and that CZ administration caused up-regulation of antioxidants and down-regulation of oxidants due to nuclear factor erythroid-2 related factor-2, as well as by enhancement of the heme oxygenase-1 mediated cascade. CZ monotherapy may play a cardioprotective role in diabetic patients. CZ possesses strong antioxidant potential that ameliorates cardiac damage induced by ISO administration.

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.

Canagliflozin alleviates experimentally induced benign prostate hyperplasia in a rat model: exploring potential mechanisms involving mir-128b/EGFR/EGF and JAK2/STAT3 signaling pathways through in silico and in vivo investigations

Benign prostatic hyperplasia (BPH) poses a significant health concern amongst elderly males. Canagliflozin (Cana), a selective sodium-glucose co-transporter 2 (SGLT2) inhibitor, has a powerful anti-inflammatory influence. Nevertheless, its role in treating BPH has not been clarified. Therefore, the study aimed to investigate the potential ameliorative effect of Cana on experimentally induced BPH in rats and explore the underlying mechanisms compared to the standard finasteride (Fin). The study employed histological analysis, biochemical assays using ELISA, and western blotting. Animals were categorized into four groups: Control (2.5 ml/kg CMC, orally + 3 ml/kg olive oil, subcutaneous), BPH (3 mg/kg testosterone, subcutaneous + CMC orally), Fin-treated BPH (5 mg/kg, orally), and Cana-treated BPH (5 mg/kg, orally), for 28 days. The BPH group showed obvious BPH manifestations including an increase in prostate weight (PW), prostate index (PI), dihydrotestosterone (DHT) level, and histological aberrations compared to control. Fin and Cana therapy had a comparable impact. Cana treatment significantly reduced PW and PI, besides it improved prostatic biochemical, and histopathological features compared to BPH, consistent with in silico study findings. Cana was associated with downregulation of the androgen axis, increased miR-128b expression, with a lowered expression of epidermal growth factor (EGF) and its receptor. Phosphorylation of STAT3 and its downstream proliferative markers were significantly reduced suggesting apoptotic activity. Cana markedly rescued the BPH-induced upregulation of IL-1β, and iNOS levels. Altogether, the current study demonstrates that Cana could impede BPH progression, possibly by modulating miR-128b/EGFR/EGF and JAK2/STAT3 pathways and downregulating AR, cyclin D1, and PCNA immunoreactivity.

The role of oxidative stress in diabetes mellitus-induced vascular endothelial dysfunction

Diabetes mellitus is a metabolic disease characterized by long-term hyperglycaemia, which leads to microangiopathy and macroangiopathy and ultimately increases the mortality of diabetic patients. Endothelial dysfunction, which has been recognized as a key factor in the pathogenesis of diabetic microangiopathy and macroangiopathy, is characterized by a reduction in NO bioavailability. Oxidative stress, which is the main pathogenic factor in diabetes, is one of the major triggers of endothelial dysfunction through the reduction in NO. In this review, we summarize the four sources of ROS in the diabetic vasculature and the underlying molecular mechanisms by which the pathogenic factors hyperglycaemia, hyperlipidaemia, adipokines and insulin resistance induce oxidative stress in endothelial cells in the context of diabetes. In addition, we discuss oxidative stress-targeted interventions, including hypoglycaemic drugs, antioxidants and lifestyle interventions, and their effects on diabetes-induced endothelial dysfunction. In summary, our review provides comprehensive insight into the roles of oxidative stress in diabetes-induced endothelial dysfunction.

Redox-driven cardioprotective effects of sodium-glucose co-transporter-2 inhibitors: comparative review

Sodium-glucose co-transporter-2 inhibitors are used in the treatment of diabetes but are also emerging as cardioprotective agents in heart diseases even in the absence of type 2 diabetes. In this paper, upon providing a short overview of common pathophysiological features of diabetes, we review the clinically reported cardio- and nephroprotective potential of sodium-glucose co-transporter-2 inhibitors currently available on the market, including Dapagliflozin, Canagliflozin, and Empagliflozin. To that end, we summarize findings of clinical trials that have initially drawn attention to the drugs' organ-protective potential, before providing an overview of their proposed mechanism of action. Since we particularly expect that their antioxidative properties will broaden the application of gliflozins from therapeutic to preventive care, special emphasis was put on this aspect.

Metabolic Syndrome and Cardiac Remodeling Due to Mitochondrial Oxidative Stress Involving Gliflozins and Sirtuins

PURPOSE OF REVIEW

To address the mechanistic pathways focusing on mitochondria dysfunction, oxidative stress, sirtuins imbalance, and other contributors in patient with metabolic syndrome and cardiovascular disease. Sodium glucose co-transporter type 2 (SGLT-2) inhibitors deeply influence these mechanisms. Recent randomized clinical trials have shown impressive results in improving cardiac function and reducing cardiovascular and renal events. These unexpected results generate the need to deepen our understanding of the molecular mechanisms able to generate these effects to help explain such significant clinical outcomes.

RECENT FINDINGS

Cardiovascular disease is highly prevalent among individuals with metabolic syndrome and diabetes. Furthermore, mitochondrial dysfunction is a principal player in its development and persistence, including the consequent cardiac remodeling and events. Another central protagonist is the renin-angiotensin system; the high angiotensin II (Ang II) activity fuel oxidative stress and local inflammatory responses. Additionally, sirtuins decline plays a pivotal role in the process; they enhance oxidative stress by regulating adaptive responses to the cellular environment and interacting with Ang II in many circumstances, including cardiac and vascular remodeling, inflammation, and fibrosis. Fasting and lower mitochondrial energy generation are conditions that substantially reduce most of the mentioned cardiometabolic syndrome disarrangements. In addition, it increases sirtuins levels, and adenosine monophosphate-activated protein kinase (AMPK) signaling stimulates hypoxia-inducible factor-1β (HIF-1 beta) and favors ketosis. All these effects favor autophagy and mitophagy, clean the cardiac cells with damaged organelles, and reduce oxidative stress and inflammatory response, giving cardiac tissue protection. In this sense, SGLT-2 inhibitors enhance the level of at least four sirtuins, some located in the mitochondria. Moreover, late evidence shows that SLGT-2 inhibitors mimic this protective process, improving mitochondria function, oxidative stress, and inflammation. Considering the previously described protection at the cardiovascular level is necessary to go deeper in the knowledge of the effects of SGLT-2 inhibitors on the mitochondria function. Various of the protective effects these drugs clearly had shown in the trials, and we briefly describe it could depend on sirtuins enhance activity, oxidative stress reduction, inflammatory process attenuation, less interstitial fibrosis, and a consequent better cardiac function. This information could encourage investigating new therapeutic strategies for metabolic syndrome, diabetes, heart and renal failure, and other diseases.

New insights and advances of sodium-glucose cotransporter 2 inhibitors in heart failure

Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are newly emerging insulin-independent anti-hyperglycemic agents that work independently of β-cells. Quite a few large-scale clinical trials have proven the cardiovascular protective function of SGLT2is in both diabetic and non-diabetic patients. By searching all relevant terms related to our topics over the previous 3 years, including all the names of agents and their brands in PubMed, here we review the mechanisms underlying the improvement of heart failure. We also discuss the interaction of various mechanisms proposed by diverse works of literature, including corresponding and opposing viewpoints to support each subtopic. The regulation of diuresis, sodium excretion, weight loss, better blood pressure control, stimulation of hematocrit and erythropoietin, metabolism remodeling, protection from structural dysregulation, and other potential mechanisms of SGLT2i contributing to heart failure improvement have all been discussed in this manuscript. Although some remain debatable or even contradictory, those newly emerging agents hold great promise for the future in cardiology-related therapies, and more research needs to be conducted to confirm their functionality, particularly in metabolism, Na⁺-H⁺ exchange protein, and myeloid angiogenic cells.

Coronary Microvascular Dysfunction in Diabetes Mellitus: Pathogenetic Mechanisms and Potential Therapeutic Options

Diabetic patients are frequently affected by coronary microvascular dysfunction (CMD), a condition consisting of a combination of altered vasomotion and long-term structural change to coronary arterioles leading to impaired regulation of blood flow in response to changing cardiomyocyte oxygen requirements. The pathogenesis of this microvascular complication is complex and not completely known, involving several alterations among which hyperglycemia and insulin resistance play particularly central roles leading to oxidative stress, inflammatory activation and altered barrier function of endothelium. CMD significantly contributes to cardiac events such as angina or infarction without obstructive coronary artery disease, as well as heart failure, especially the phenotype associated with preserved ejection fraction, which greatly impact cardiovascular (CV) prognosis. To date, no treatments specifically target this vascular damage, but recent experimental studies and some clinical investigations have produced data in favor of potential beneficial effects on coronary micro vessels caused by two classes of glucose-lowering drugs: glucagon-like peptide 1 (GLP-1)-based therapy and inhibitors of sodium-glucose cotransporter-2 (SGLT2). The purpose of this review is to describe pathophysiological mechanisms, clinical manifestations of CMD with particular reference to diabetes, and to summarize the protective effects of antidiabetic drugs on the myocardial microvascular compartment.

Lack of renoprotective effects of targeting the endothelin A receptor and (or) sodium glucose transporter 2 in a mouse model of Type 2 diabetic kidney disease

Two recent clinical trials, using sodium glucose cotransporter (SGLT2) or endothelin-A receptor (ET-A) blocker, reported the first efficacious treatments in 18 years to slow progression of diabetic kidney disease (DKD). We hypothesized that combined inhibition of SGLT2 and ET-A receptor may confer greater protection against renal injury than either agent alone. Uninephrectomized male db/db mice were randomized to four groups: vehicle, SGLT2 inhibitor (dapagliflozin (dapa), 1 mg/kg/day), ET-A blocker (atrasentan (atra), 5 mg/kg/day), or dual treatment from 10 weeks until 22 weeks of age. At 10 weeks of age, no differences were observed in body weight, blood glucose or urinary albumin excretion among the four groups. At 16 and 22 weeks of age, body weight was lower and blood glucose levels higher in the vehicle and atra groups compared with dapa- and dual-treated groups. No notable differences were observed among the four groups in urinary albumin excretion at weeks 16 and 22. Histological analysis showed mild glomerulosclerosis and tubular injury (<5%) in all four groups with reduced glomerulosclerosis in the dual treatment group compared with vehicle. Individual or combined treatment with an SGLT2 inhibitor and (or) an ET-A antagonist did not confer renoprotective effects in this model.

Empagliflozin mitigates endothelial inflammation and attenuates endoplasmic reticulum stress signaling caused by sustained glycocalyx disruption

The disruption of the endothelial cell (EC) glycocalyx (GCX) leads to cellular dysfunction promoting inflammation and cardiovascular disease progression. Recent studies have shown that empagliflozin (EMPA; Jardiance), a sodium-glucose cotransporter 2 inhibitor used in the treatment of type 2 diabetes, can improve EC functions impacted by GCX disruption although the exact cellular mechanisms remain to be elucidated. In this study, the effect of EMPA on EC inflammatory response induced by sustained GCX disruption was investigated. Human aortic ECs were cultured under shear (10 dyne/cm²) for 24 h with or without sustained degradation of heparan sulfate (HS). HS degradation increased inflammatory cell adhesion to ECs. EMPA (50 μM) normalized adhesion levels under sustained HS degradation. Protein expressions of eNOS, phospho-eNOS Ser1177 and ICAM-1 remained unchanged between conditions. Transcriptome analysis revealed the induction of the unfolded protein response (UPR) through the increased expression of ATF3, ATF4, DDIT3 (CHOP), EIF2AK3 (PERK), HSPA5 (Grp78), PPP1R15A (GADD34) and TRIB3 which was in part downregulated by EMPA. mRNA and protein expression of thioredoxin interacting protein (TXNIP) was also downregulated by EMPA. Mitigation of oxidative stress with N-Acetyl-L-cysteine resulted in similar reduction in inflammatory cell adhesion compared to EMPA which could indicate a potential mechanism by which EMPA normalized the inflammatory response. In conclusion, this study demonstrated the potential of EMPA to resolve the inflammatory response of ECs caused by sustained GCX disruption while altering UPR signaling under endoplasmic reticulum stress.

Dihydromyricetin protects against high glucose-induced endothelial dysfunction: Role of HIF-1α/ROR2/NF-κB

OBJECTIVES

Dihydromyricetin (DHM), a natural flavonoid isolated from vine tea with anti-inflammatory activity was evaluated for its ability to prevent vascular endothelial dysfunction caused by hyperglycaemia.

METHODS

Vasoconstrictor (phenylephrine-PE) and vasodilator (acetylcholine-ACh) responses were monitored for female rat aorta rings maintained in a bioassay organ bath for 3 h at 37 °C in either low (LG: 10 mM) or high (HG: 40 mM, to mimic hyperglycaemia) glucose-Krebs buffer in the absence or presence of 50 µM DHM. Tissues recovered from the organ bath at 3 h were fixed and analyzed for morphological changes and their expression of eNOS, iNOS, HIF-1α, GLUT1, ROR2 tyrosine kinase, NF-κB, TNF-α, Bax, Bcl2, caspase-3, and forindices of increased oxidative stress.

KEY FINDINGS

HG-incubated tissues showed increased PE-stimulated contractile response and decreased ACh-mediated endothelial vasodilation. DHM prevented both of these changes. Besides, HG incubation increased the immunoreactivity to iNOS, HIF-1α, GLUT1, ROR2, NF-κB, TNF-α, Bax, and active caspase-3, and decreased the expression of eNOS and Bcl2. Hyperglycaemia-like conditions also increased the indices of oxidative/nitrosative stress. These HG-induced changes, which were accompanied by an increase in tissue adventitial thickness and inflammatory cell infiltration, were all prevented by DHM.

CONCLUSION

Our data demonstrate an anti-inflammatory protective action of DHM to preserve vascular function in the setting of hyperglycaemia.

Design of the COmbinatioN effect of FInerenone anD EmpaglifloziN in participants with chronic kidney disease and type 2 diabetes using an UACR Endpoint study (CONFIDENCE)

BACKGROUND

Despite available interventions, people with type 2 diabetes (T2D) remain at risk of chronic kidney disease (CKD). Finerenone, a potent and selective nonsteroidal mineralocorticoid receptor antagonist, and sodium-glucose co-transporter 2 inhibitors (SGLT2is) can reduce both kidney and cardiovascular risks in people with CKD and T2D. Here we outline the design of a study to investigate whether dual therapy with finerenone and a SGLT2i is superior to either agent alone.

METHODS

CONFIDENCE (NCT05254002) is a randomized, controlled, double-blind, double-dummy, international, multicentre, three-armed, parallel-group, 7.5-8.5-month, Phase 2 study in approximately 807 adults with T2D, stage 2-3 CKD and a urine albumin-to-creatinine ratio (UACR) from ≥ 300-<5000 mg/g. The primary objective is to demonstrate that 6 months' dual therapy comprising finerenone and the SGLT2i empagliflozin is superior for reducing albuminuria versus either agent alone. Interventions will be once-daily finerenone 10 mg or 20 mg (target dose) plus empagliflozin 10 mg, or empagliflozin 10 mg alone, or finerenone 10 mg or 20 mg (target dose) alone.

RESULTS

The primary outcome is relative change from baseline in UACR among the three groups. Secondary outcomes will further characterize efficacy and safety, including change in eGFR and incident hyperkalaemia.

CONCLUSIONS

CONFIDENCE is evaluating the safety, tolerability and efficacy of dual use of finerenone and a SGLT2i in adults with CKD and T2D. Should an additive effect be shown, early and efficient intervention with dual finerenone and SGLT2i therapy could slow disease progression and provide long-term benefits for people with CKD and T2D.

Challenges facing the clinical translation of cardioprotection: 35 years after the discovery of ischemic preconditioning

Since coronary reperfusion was introduced into clinical practice in the late 1970s, the further translation of several successful animal experiments on cardioprotection into clinical practice has been disappointing to date. Animal experiments are often performed on young, healthy animals lacking the risk factors, co-morbidities and co-medications characteristic of acute myocardial infarction patients. Many hopes were kindled in 1986 when ischemic preconditioning was discovered. However, it is not yet known how long ischemia can last and what is the best modality for additional cardioprotection through conditioning to obtain benefits. There is a lack of experimental studies on the long-term effects of additional cardioprotection, in addition to the reduction in infarct size; in particular, there is a lack of studies on vessel protection, repair, inflammation, remodeling, and mortality. The reproducibility and robustness of experimental studies are often limited by species differences, the role of co-morbidities, vascular damage, inflammatory processes, and co-medications, which are not adequately considered. In particular, inflammatory processes, including NLRP3 inflammasome, play an important role in the long-term effects. Future studies should focus on interventions/agents with robust preclinical data and should recruit patients who truly have the potential to benefit from further cardioprotection. Here we focus on the main mechanisms and targets of cardioprotection during remote conditioning and their alteration by one of the most common co-morbidities, namely diabetes, in which microvascular lesions and inflammatory processes play extremely important roles.

Effects of dietary palmitoleic acid on vascular function in aorta of diabetic mice

BACKGROUND

Chronic hyperglycemia in diabetes causes atherosclerosis and progresses to diabetic macroangiopathy, and can lead to coronary heart disease, myocardial infarction and cerebrovascular disease. Palmitoleic acid (POA) is a product of endogenous lipogenesis and is present in fish and vegetable oil. In human and animal studies, POA is reported as a beneficial fatty acid related to insulin sensitivity and glucose tolerance. However, few studies have reported its effects on aortic function in diabetes. Here, we investigated the effects of POA administration on vascular function in KKAy mice, a model of type 2 diabetes.

METHODS

Male C57BL/6 J (control) and KKAy (experimental) mice at the age of 14 weeks were used in the present study. For each mouse strain, one group was fed with reference diet and a second group was fed POA-containing diet for 2 weeks. The vascular reactivities of prepared aortic rings were then measured in an organ bath to determine if POA administration changed vascular function in these mice.

RESULTS

KKAy mice treated with POA exhibited decreased plasma glucose levels compared with mice treated with reference diet. However, endothelium-dependent vasorelaxant responses to acetylcholine and protease-activated receptor 2 activating protein, which are attenuated in the aorta of KKAy mice compared to C57BL/6 J mice under a reference diet, were not affected by a 2-week POA treatment. In addition, assessment of vasoconstriction revealed that the phenylephrine-induced vasoconstrictive response was enhanced in KKAy mice compared to C57BL/6 J mice under a reference diet, but no effect was observed in KKAy mice fed a POA-containing diet. In contrast, there was an increase in vasoconstriction in C57BL/6 J mice fed the POA-containing diet compared to mice fed a reference diet. Furthermore, the vasoconstriction in aorta in both C57BL/6 J and KKAy mice fed a POA-containing diet were further enhanced under hyperglycemic conditions compared to normal glucose conditions in vitro. In the hyperinsulinemic, and hyperinsulinemic combined with hyperglycemic conditions, vasoconstriction was increased in KKAy mice fed with POA.

CONCLUSION

These results suggest that POA intake enhances vasoconstriction under hyperglycemic and hyperinsulinemic conditions, which are characteristics of type 2 diabetes, and may contribute to increased vascular complications in diabetes.

Cellular interplay between cardiomyocytes and non-myocytes in diabetic cardiomyopathy

Patients with Type 2 diabetes mellitus (T2DM) frequently exhibit a distinctive cardiac phenotype known as diabetic cardiomyopathy. Cardiac complications associated with T2DM include cardiac inflammation, hypertrophy, fibrosis and diastolic dysfunction in the early stages of the disease, which can progress to systolic dysfunction and heart failure. Effective therapeutic options for diabetic cardiomyopathy are limited and often have conflicting results. The lack of effective treatments for diabetic cardiomyopathy is due in part, to our poor understanding of the disease development and progression, as well as a lack of robust and valid preclinical human models that can accurately recapitulate the pathophysiology of the human heart. In addition to cardiomyocytes, the heart contains a heterogeneous population of non-myocytes including fibroblasts, vascular cells, autonomic neurons and immune cells. These cardiac non-myocytes play important roles in cardiac homeostasis and disease, yet the effect of hyperglycaemia and hyperlipidaemia on these cell types are often overlooked in preclinical models of diabetic cardiomyopathy. The advent of human induced pluripotent stem cells provides a new paradigm in which to model diabetic cardiomyopathy as they can be differentiated into all cell types in the human heart. This review will discuss the roles of cardiac non-myocytes and their dynamic intercellular interactions in the pathogenesis of diabetic cardiomyopathy. We will also discuss the use of sodium-glucose cotransporter 2 inhibitors as a therapy for diabetic cardiomyopathy and their known impacts on non-myocytes. These developments will no doubt facilitate the discovery of novel treatment targets for preventing the onset and progression of diabetic cardiomyopathy.

Comparative Efficacy of Dapagliflozin and Empagliflozin of a Fixed Dose in Heart Failure: A Network Meta-Analysis

Background

The efficacy of dapagliflozin and empagliflozin in sodium-glucose cotransport-2 inhibitors (SGLT-2i) in patients with heart failure (HF) has been discovered. However, which drug could improve varied prognostic outcomes has not been elucidated. Hence, we compared their efficacies on the prognostic improvement of HF.

Methods

Databases including PubMed, EMBASE, Scopus, Google Scholars, and the Cochrane Library were searched for all related randomized controlled trials (RCTs) published from inception to 13 October 2021. Network meta-analyses were performed to generate matrices to show the effect size for pairwise comparison regarding all the interventions.

Results

Eventually a total of 11 RCTs were included in this study. For the primary endpoints, dapagliflozin was comparable with empagliflozin in hospitalization for HF, and empagliflozin (OR=0.70, 95%CI: 0.59-0.84) decreased the risk of exacerbation of HF over dapagliflozin. For the secondary endpoints, dapagliflozin was comparable with empagliflozin in cardiovascular (CV) death /hospitalization for HF, and for CV death, dapagliflozin (OR=0.78, 95%CI: 0.65-0.92) significantly reduced mortality over the placebo. For the tertiary endpoints, dapagliflozin (OR=0.80, 95%CI: 0.66-0.98) significantly decreased the mortality over empagliflozin in all-cause death, and neither drug significantly increased the risk of hypoglycemia.

Recommendations

Overall, 10 mg/day dapagliflozin may be the optimal recommendation for its premium and comprehensive effect on improving the prognosis of patients with HF compared to 10 mg/day empagliflozin.

The innate immune response, microenvironment proteinases, and the COVID-19 pandemic: pathophysiologic mechanisms and emerging therapeutic targets

The coronavirus disease 2019 (COVID-19) pandemic, causing considerable mortality and morbidity worldwide, has fully engaged the biomedical community in attempts to elucidate the pathophysiology of COVID-19 and develop robust therapeutic strategies. To this end, the predominant research focus has been on the adaptive immune response to COVID-19 infections stimulated by mRNA and protein vaccines and on the duration and persistence of immune protection. In contrast, the role of the innate immune response to the viral challenge has been underrepresented. This overview focuses on the innate immune response to COVID-19 infection, with an emphasis on the roles of extracellular proteases in the tissue microenvironment. Proteinase-mediated signaling caused by enzymes in the extracellular microenvironment occurs upstream of the increased production of inflammatory cytokines that mediate COVID-19 pathology. These enzymes include the coagulation cascade, kinin-generating plasma kallikrein, and the complement system, as well as angiotensin-generating proteinases of the renin-angiotensin system. Furthermore, in the context of several articles in this Supplement elucidating and detailing the trajectory of diverse profibrotic pathways, we extrapolate these insights to explore how fibrosis and profibrotic pathways participate importantly in the pathogenesis of COVID-19. We propose that the lessons garnered from understanding the roles of microenvironment proteinases in triggering the innate immune response to COVID-19 pathology will identify potential therapeutic targets and inform approaches to the clinical management of COVID-19. Furthermore, the information may also provide a template for understanding the determinants of COVID-19-induced tissue fibrosis that may follow resolution of acute infection (so-called "long COVID"), which represents a major new challenge to our healthcare systems.

Inhibition of Protease Activated Receptor 2 Attenuates HBx-Induced Inflammation and Mitochondria Oxidative Stress

BACKGROUND

Hepatitis B virus (HBV) infection is one of the global public problems. Among the known infection cases, HBV X protein (HBx) is one of the key inducements of viral replication and host infection. This study was aimed to uncover the role of protease activated receptor 2 (PAR2) on HBx-induced liver injury.

METHODS

A PAR2-KO mouse model expressing HBx was constructed using hydrodynamics-based in vivo gene transfection method. In addition, pcDNA3.1-HBx was used to over-express HBx in LO2 cells. The effects of HBx overexpression on inflammation and mitochondria oxidative stress were evaluated.

RESULTS

We found that PAR2 protein level was increased by HBx overexpression. The enforced HBx inhibited LO2 cells apoptosis. Meanwhile, HBx induced inflammation reactions through promoting the secretion of pro-inflammatory cytokines such as TNF-α, IL-6, and CXCL-2. Overexpressed HBx also resulted in mitochondria oxidative stress by upregulation of ROS level and downregulation of MMP and ATP. However, in FSLLRY-NH2 (PAR2 antagonist) treated LO2 cells or PAR2-KO mice, PAR2 blockade reversed the above adverse effects of HBx on liver cells or tissues.

CONCLUSION

Inhibition of PAR2 may suppress inflammation and mitochondria oxidative stress caused by HBx, pointing out the potential application values of PAR2 antagonist on the treatment of HBV infection in clinic.

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.

Mechanisms underlying the vasodilatory effects of canagliflozin in the rabbit thoracic aorta: Involvement of the SERCA pump and Kv channels

AIMS

Canagliflozin is an anti-diabetic agent and sodium glucose co-transporter-2 inhibitor. Despite numerous clinical trials demonstrating its beneficial effects on blood pressure, the cellular mechanisms underlying the effects of canagliflozin on vascular reactivity have yet to be clarified. We investigated the vasodilatory effect of canagliflozin on aortic rings isolated from rabbits.

MAIN METHODS

We used rabbit thoracic aortic rings and its arterial tone was tested by using wire myography system.

KEY FINDINGS

Canagliflozin caused concentration-dependent vasodilation in aortic rings pre-constricted with phenylephrine or high K⁺. However, the degree of canagliflozin-induced vasodilation of the aortic rings pre-constricted with high K⁺ was less than that of rings pre-constricted with phenylephrine. Application of 4-aminopyridine, a voltage-dependent K⁺ (Kv) channel inhibitor, reduced canagliflozin-induced vasodilation. However, pre-incubation of an inwardly rectifying K⁺ channel inhibitor, a large-conductance Ca²⁺-activated K⁺ channel inhibitor, and an ATP-sensitive K⁺ inhibitor did not modulate the vasodilatory effects of canagliflozin. Indeed, canagliflozin increased Kv currents in aortic smooth muscle cells. Pre-treatment with thapsigargin or cyclopiazonic acid, a sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) pump inhibitors, reduced the vasodilatory effects of canagliflozin. Conversely, pre-treatment with a Ca²⁺ channel inhibitor, adenylyl cyclase/PKA inhibitors, and guanylyl cyclase/PKG inhibitors did not modulate the vasodilatory effects of canagliflozin. Endothelium removal, and pre-treatment with the nitric oxide synthase inhibitor L-NAME, and small- and intermediate-conductance Ca²⁺-activated K⁺ channel inhibitor apamin and TRAM-34, did not diminish the vasodilatory effects of canagliflozin.

SIGNIFICANCE

Our results indicate that canagliflozin induces vasodilation, which is dependent on the robust SERCA activity and Kv channel activation.

Exploring the Correlation and Protective Role of Diabetes Mellitus in Aortic Aneurysm Disease

Introduction: Diabetes mellitus is recognised as a significant risk factor for cardiovascular and peripheral vascular disease, as the abnormal metabolic state increases the risk for atherosclerosis, occlusive arterial disease and vascular dysfunction. There have been reports of potential association across the literature that illustrates a link between diabetes mellitus and aortic aneurysm, with the former having a protective role on the development of the latter.

Methods: A thorough literature search was performed through electronic databases, to provide a comprehensive review of the study's reporting on the association of diabetes mellitus and aortic aneurysm, discussing the mechanisms that have been reported; furthemore, we reviewed the reports of the impact of oral hypoglycameic agents on aortic aneurysms.

Results: Various proposed mechanisms are involved in this protective process including endothelial dysfunction, chronic hyperglycemia and insulin resistance. The evidence suggests a negative association between these disease process, with prevelance of diabetes mellitus resulting in lower rates of aortic aneurysm, via its protective mechanistic action. The increase in advanced glycation end products, increased arterial stiffness and vascular remodelling seen in diabetes, was found to have a profound impact on aneurysm development, its slow progression and lower rupture rate in these individuals. This review has also highlighted the role of oral hypoglycaemic agents having a protective effect against AA disease.

Conclusion: A decrease in development, progression and mortality from aortic aneurysms as well as reduced rates of dissection, have been observed in those with diabetes. This review has provided a comprehensive insight on the effect of diabetes and its physiological processes, and elements of its con-committant treatment, having a protective role against these aortic diseases.

Metformin Prevents Hyperglycemia-Associated, Oxidative Stress-Induced Vascular Endothelial Dysfunction: Essential Role for the Orphan Nuclear Receptor Human Nuclear Receptor 4A1 (Nur77)

Vascular pathology is increased in diabetes because of reactive-oxygen-species (ROS)-induced endothelial cell damage. We found that in vitro and in a streptozotocin diabetes model in vivo, metformin at diabetes-therapeutic concentrations (1-50 µM) protects tissue-intact and cultured vascular endothelial cells from hyperglycemia/ROS-induced dysfunction typified by reduced agonist-stimulated endothelium-dependent, nitric oxide-mediated vasorelaxation in response to muscarinic or proteinase-activated-receptor 2 agonists. Metformin not only attenuated hyperglycemia-induced ROS production in aorta-derived endothelial cell cultures but also prevented hyperglycemia-induced endothelial mitochondrial dysfunction (reduced oxygen consumption rate). These endothelium-protective effects of metformin were absent in orphan-nuclear-receptor Nr4a1-null murine aorta tissues in accord with our observing a direct metformin-Nr4a1 interaction. Using in silico modeling of metformin-NR4A1 interactions, Nr4a1-mutagenesis, and a transfected human embryonic kidney 293T cell functional assay for metformin-activated Nr4a1, we identified two Nr4a1 prolines, P505/P549 (mouse sequences corresponding to human P501/P546), as key residues for enabling metformin to affect mitochondrial function. Our data indicate a critical role for Nr4a1 in metformin's endothelial-protective effects observed at micromolar concentrations, which activate AMPKinase but do not affect mitochondrial complex-I or complex-III oxygen consumption rates, as does 0.5 mM metformin. Thus, therapeutic metformin concentrations requiring the expression of Nr4a1 protect the vasculature from hyperglycemia-induced dysfunction in addition to metformin's action to enhance insulin action in patients with diabetes. SIGNIFICANCE STATEMENT: Metformin improves diabetic vasodilator function, having cardioprotective effects beyond glycemic control, but its mechanism to do so is unknown. We found that metformin at therapeutic concentrations (1-50µM) prevents hyperglycemia-induced endothelial dysfunction by attenuating reactive oxygen species-induced damage, whereas high metformin (>250 µM) impairs vascular function. However, metformin's action requires the expression of the orphan nuclear receptor NR4A1/Nur77. Our data reveal a novel mechanism whereby metformin preserves diabetic vascular endothelial function, with implications for developing new metformin-related therapeutic agents.

Dapagliflozin Reduces Urinary Albumin Excretion by Downregulating the Expression of cAMP, MAPK, and cGMP-PKG Signaling Pathways Associated Genes

Objective: Diabetic nephropathy (DN), the most severe complication of diabetes mellitus, is characterized by albuminuria and progressive loss of kidney function. Dapagliflozin (DAP), a sodium-glucose cotransporter inhibitor, is an oral medication that improves blood glucose control in diabetic patients. However, the effects and mechanisms of DAP on DN remain unclear. Materials and Methods: The effect of DAP was based on a retrospective cohort study of patients who underwent 2-year surveillance, and the concentration of urine albumin-to-creatinine ratio, glomerular filtration rate, and serum creatinine were collected after treatment with DAP. To investigate the underlying mechanisms through which DAP reduces urinary albumin excretion, we used RNA-sequencing (RNA-seq) to analyze gene expression in human kidney 2 (HK-2) cells treated with DAP. Results: The retrospective cohort analysis indicated that DAP could reduce the excretion rate of urinary albumin in patients with type 2 diabetes and renal impairment. The results of the RNA-seq experiments showed 349 differentially expressed genes between DAP-treated HK-2 cells and control cells. Gene ontology annotation enrichment analysis showed that DAP mainly affected the expression of integral component of membrane- and cell junction-related genes, while the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that DAP primarily downregulated the expression of gene clusters associated with cyclic adenosine monophosphate, mitogen-activated protein kinase, and cyclic guanosine monophosphate-protein kinase G signaling pathways, which play critical roles in the progression of DN. Conclusion: Our results shed light on the mechanism by which DAP controls DN progression and provide a theoretical basis for the clinical treatment of DN.

The Role of Sodium Glucose Cotransporter-2 Inhibitors in Atherosclerotic Cardiovascular Disease: A Narrative Review of Potential Mechanisms

Sodium glucose cotransporter 2 (SGLT2) inhibitors are a class of medication with broad cardiovascular benefits in those with type 2 diabetes, chronic kidney disease, and heart failure. These include reductions in major adverse cardiac events and cardiovascular death. The mechanisms that underlie their benefits in atherosclerotic cardiovascular disease (ASCVD) are not well understood, but they extend beyond glucose lowering. This narrative review summarises the ASCVD benefits of SGLT2 inhibitors seen in large human outcome trials, as well as the mechanisms of action explored in rodent and small human studies. Potential pathways include favourable alterations in lipid metabolism, inflammation, and endothelial function. These all require further investigation in large human clinical trials with mechanistic endpoints, to further elucidate the disease modifying benefits of this drug class and those who will benefit most from it.

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

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