Effects of Dapagliflozin on Endothelial Dysfunction in Type 2 Diabetes With Established Ischemic Heart Disease (EDIFIED)

The effect of sodium-glucose cotransporter-2 inhibitors on inflammatory biomarkers: A meta-analysis of randomized controlled trials

AIMS

To conduct a meta-analysis of randomized controlled trials (RCTs) to assess the effect of sodium-glucose cotransporter-2 (SGLT2) inhibitors on inflammatory biomarkers.

METHODS

Medline, Embase and the Cochrane Library were searched for RCTs investigating the effect of SGLT2 inhibitors on inflammatory biomarkers, adipokine profiles and insulin sensitivity.

RESULTS

Thirty-eight RCTs were included (14 967 participants, 63.3% male, mean age 62 ± 8.6 years) with a median (interquartile range) follow-up of 16 (12-24) weeks. Meta-analysis showed that SGLT2 inhibitors significantly improved adiponectin, interleukin-6, tumour necrosis factor receptor-1 (vs. placebo alone: standardized mean difference [SMD] 0.34 [95% confidence interval {CI} 0.23, 0.45], mean difference [MD] -0.85 pg/mL [95% CI -1.32, -0.38], SMD -0.13 [95% CI -0.20, -0.06], respectively), leptin and homeostatic model assessment of insulin resistance index (vs.

CONTROL

SMD -0.20 [95% CI -0.33, -0.07], MD -0.83 [95% CI -1.32, -0.33], respectively). There were no significant changes in C-reactive protein (CRP), tumour necrosis factor-α, plasminogen activator inhibitor-1, fibroblast growth factor-21 or monocyte chemoattractant protein-1.

CONCLUSIONS

Our analysis shows that SGLT2 inhibitors likely improve adipokine biomarkers and insulin sensitivity, but there is little evidence that SGLT2 inhibitors improve other inflammatory biomarkers including CRP.

SGLT2-inhibition increases total, LDL, and HDL cholesterol and lowers triglycerides: Meta-analyses of 60 randomized trials, overall and by dose, ethnicity, and drug type

BACKGROUND AND AIMS

Sodium glucose co-transporter 2 (SGLT2)-inhibitors were developed as glucose-lowering drugs. Surprisingly, SGLT2-inhibitors also reduced risk of cardiovascular disease. The impact of SGLT2-inhibitors on lipids and lipoproteins is unclear, but an effect might contribute to the observed lower cardiovascular risk. We conducted a meta-analysis to examine this, overall and by dose, ethnicity, and drug type.

METHODS

PubMed, EMBASE and Web of Science were searched for randomized controlled trials examining all available SGLT2-inhibitors. Studies with available lipid measurements were included. Quantitative data synthesis was performed using random and fixed effects models.

RESULTS

We identified 60 randomized trials, including 147,130 individuals. Overall, using random effects models, SGLT2-inhibitor treatment increased total cholesterol by 0.09 mmol/L (95% CI: 0.06, 0.13), low-density lipoprotein (LDL) cholesterol by 0.08 mmol/L (0.05, 0.10), and high-density lipoprotein (HDL) cholesterol by 0.06 mmol/L (0.05, 0.07), while it reduced triglycerides by 0.10 mmol/L (0.06, 0.14). Fixed effects estimates were similar but with smaller effect sizes for HDL cholesterol and triglycerides. For higher SGLT2-inhibitor doses, there was a nominally higher non-significant effect on lipids and lipoproteins. In Asian compared to non-Asian populations, a slightly larger increase in HDL cholesterol and a decrease in triglycerides were observed, but with similar results for total and LDL cholesterol. Treatment effects on lipids and lipoproteins were generally robust across different SGLT2-inhibitor drugs.

CONCLUSION

In meta-analyses, SGLT2-inhibition increased total, LDL, and HDL cholesterol and decreased triglycerides. Effect sizes varied slightly by drug dose and ethnicity but were generally robust by drug type.

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.

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.

Dapagliflozin-entresto protected kidney from renal hypertension via downregulating cell-stress signaling and upregulating SIRT1/PGC-1α/Mfn2-medicated mitochondrial homeostasis

This study tested whether combined dapagliflozin and entresto would be superior to mere one therapy on protecting the residual renal function and integrity of kidney parenchyma in hypertensive kidney disease (HKD) rat. In vitro results showed that the protein expressions of oxidative-stress/mitochondrial-damaged (NOX-1/NOX-2/oxidized-protein/cytosolic-cytochrome-C)/apoptotic (mitochondrial-Bax/cleaved caspeases 3, 9)/cell-stress (p-ERK/p-JNK/p-p38) biomarkers were significantly increased in H2O2-treated NRK-52E cells than those of controls that were reversed by dapagliflozin or entresto treatment. Adult-male SD rats (n = 50) were equally categorized into group 1 (sham-operated-control), group 2 (HKD by 5/6 nephrectomy + DOCA-salt/25 mg/kg/subcutaneous injection/twice weekly), group 3 (HKD + dapagliflozin/orally, 20 mg/kg/day for 4 weeks since day 7 after HKD induction), group 4 (HKD + entresto/orally, 100 mg/kg/day for 4 weeks since day 7 after HKD induction), and group 5 (HKD + dapagliflozin + entresto/the procedure and treatment strategy were identical to groups 2/3/4). By day 35, circulatory levels of blood-urine-nitrogen (BUN)/creatinine and urine protein/creatinine ratio were lowest in group 1, highest in group 2, and significantly lower in group 5 than in groups 3/4, but no difference between groups 3/4. Histopathological findings showed the kidney injury score/fibrotic area/cellular expressions of oxidative-stress/kidney-injury-molecule (8-OHdG+/KIM-1+) exhibited an identical trend, whereas the cellular expressions of podocyte components (synaptopodin/ZO-1/E-cadherin) exhibited an opposite pattern of BUN level among the groups. The protein expressions of oxidative stress/mitochondrial-damaged (NOX-1/NOX-2/oxidized protein/cytosolic-cytochrome-C/cyclophilin-D)/apoptotic (mitochondrial-Bax/cleaved-caspase 3)/mitochondrial-fission (PINK1/Parkin/p-DRP1)/autophagic (LC3BII/LC3BI ratio, Atg5/beclin-1)/MAPK-family (p-ERK/p-JNK/p-p38) biomarkers displayed a similar pattern, whereas the protein expression of mitochondria-biogenesis signaling (SIRT1/PGC-1α-Mfn2/complex I-V) displayed an opposite pattern of BUN among the groups. In conclusion, combined dapagliflozin-entresto therapy offered additional benefits on protecting the residual kidney function and architectural integrity in HKD rat.

SIRT1 mediates the inhibitory effect of Dapagliflozin on EndMT by inhibiting the acetylation of endothelium Notch1

BACKGROUND

Endothelial-mesenchymal transition (EndMT) plays a crucial role in promoting myocardial fibrosis and exacerbating cardiac dysfunction. Dapagliflozin (DAPA) is a sodium-glucose-linked transporter 2 (SGLT-2) inhibitor that has been shown to improve cardiac function in non-diabetic patients with heart failure (HF). However, the precise mechanisms by which DAPA exerts its beneficial effects are yet to be fully elucidated.

METHODS

Isoproterenol (ISO) was used to generate a HF model in mice. For in vitro experiments, we used TGF-β1-stimulated human umbilical vein endothelial cells (HUVECs) and mouse aortic endothelial cells (MAECs).

RESULTS

Both our in vivo and in vitro results showed that EndMT occurred with decreased SIRT1 (NAD+-dependent deacetylase) protein expression, which could be reversed by DAPA therapy. We found that the protective effect of DAPA was significantly impaired upon SIRT1 inhibition. Mechanistically, we observed that SIRT1 phosphorylation, a required modification for its ubiquitination and degradation, was reduced by DAPA treatment, which induces the nucleus translocation of SIRT1 and promotes its binding to the active intracellular domain of Notch1 (NICD). This interaction led to the deacetylation and degradation of NICD, and the subsequent inactivation of the Notch1 signaling pathway which contributes to ameliorating EndMT.

CONCLUSIONS

Our study revealed that DAPA can attenuate EndMT induced by ISO in non-diabetic HF mice. This beneficial effect is achieved through SIRT1-mediated deacetylation and degradation of NICD. Our findings provide greater insight into the underlying mechanisms of the therapeutic effects of DAPA in non-diabetic HF.

Changes in Cardiovascular and Renal Biomarkers Associated with SGLT2 Inhibitors Treatment in Patients with Type 2 Diabetes Mellitus

Type 2 diabetes mellitus is a major health problem worldwide with a steadily increasing prevalence reaching epidemic proportions. The major concern is the increased morbidity and mortality due to diabetic complications. Traditional but also nontraditional risk factors have been proposed to explain the pathogenesis of type 2 diabetes mellitus and its complications. Hyperglycemia has been considered an important risk factor, and the strict glycemic control can have a positive impact on microangiopathy but not macroangiopathy and its related morbidity and mortality. Thus, the therapeutic algorithm has shifted focus from a glucose-centered approach to a strategy that now emphasizes target-organ protection. Sodium-glucose transporter 2 inhibitors is an extremely important class of antidiabetic medications that, in addition to their glucose lowering effect, also exhibit cardio- and renoprotective effects. Various established and novel biomarkers have been described, reflecting kidney and cardiovascular function. In this review, we investigated the changes in established but also novel biomarkers of kidney, heart and vascular function associated with sodium-glucose transporter 2 inhibitors treatment in patients with type 2 diabetes mellitus.

Lack of impact of ipragliflozin on endothelial function in patients with type 2 diabetes: sub-analysis of the PROTECT study

BACKGROUND

We assessed the impact of 24 months of treatment with ipragliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, on endothelial function in patients with type 2 diabetes as a sub-analysis of the PROTECT study.

METHODS

In the PROTECT study, patients were randomized to receive either standard antihyperglycemic treatment (control group, n = 241 ) or add-on ipragliflozin treatment (ipragliflozin group, n = 241) in a 1:1 ratio. Among the 482 patients in the PROTECT study, flow-mediated vasodilation (FMD) was assessed in 32 patients in the control group and 26 patients in the ipragliflozin group before and after 24 months of treatment.

RESULTS

HbA1c levels significantly decreased after 24 months of treatment compared to the baseline value in the ipragliflozin group, but not in the control group. However, there was no significant difference between the changes in HbA1c levels in the two groups (7.4 ± 0.8% vs. 7.0 ± 0.9% in the ipragliflozin group and 7.4 ± 0.7% vs. 7.3 ± 0.7% in the control group; P = 0.08). There was no significant difference between FMD values at baseline and after 24 months in both groups (5.2 ± 2.6% vs. 5.2 ± 2.6%, P = 0.98 in the ipragliflozin group; 5.4 ± 2.9% vs. 5.0 ± 3.2%, P = 0.34 in the control group). There was no significant difference in the estimated percentage change in FMD between the two groups (P = 0.77).

CONCLUSIONS

Over a 24-month period, the addition of ipragliflozin to standard therapy in patients with type 2 diabetes did not change endothelial function assessed by FMD in the brachial artery.

TRIAL REGISTRATION

Registration Number for Clinical Trial: jRCT1071220089 ( https://jrct.niph.go.jp/en-latest-detail/jRCT1071220089 ).

Role of hypoxia inducible factor/vascular endothelial growth factor/endothelial nitric oxide synthase signaling pathway in mediating the cardioprotective effect of dapagliflozin in cyclophosphamide-induced cardiotoxicity

BACKGROUND

Cyclophosphamide (CP) is a commonly used chemotherapeutic and immunosuppressive alkylating agent. However, cardiac adverse effects of CP interfere with its clinical benefit. Cardio-oncology research is currently an important issue and finding effective cardiopreserving agents is a critical need. For the first time, we aimed to detect if dapagliflozin (DAP) could ameliorate CP-induced cardiac injury and investigated the role of hypoxia inducible factor α (HIF1α)/vascular endothelial growth factor (VEGF)/endothelial nitric oxide synthase (eNOS) pathway.

METHODS

Forty male Wistar albino rats were included in the current model. Studied groups are: control group; CP-induced cardiotoxicity group; CP group treated with DAP; CP group treated with DAP and administered a nitric oxide synthase inhibitor; nitro-ω-L-arginine (L-NNA) before DAP to explore the role of eNOS.

RESULTS

Our data revealed that CP could induce cardiac damage as manifested by significant increases in cardiac enzymes, blood pressure, malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), HIF1α, sodium glucose co-transporter 2 (SGLT2) and cleaved caspase-3 levels with toxic histopathological changes. However, there are significant decreases in reduced glutathione (GSH), total antioxidant capacity (TAC), VEGF, and eNOS. On the opposite side, co-administration of DAP showed marked improvement of CP-induced cardiac damage that may be due to its ability to inhibit SGLT2, antioxidant, anti-inflammatory and anti-apoptotic properties. Results showed decreasing the cardioprotective effect of DAP on administration of L-NNA, reflecting the critical effect of eNOS in mediating such protection.

CONCLUSION

DAP could reduce CP cardiotoxicity based upon its ability to modulate SGLT2 and HIF1α/VEGF/eNOS signaling pathway.

SGLT2 inhibitors protect cardiomyocytes from myocardial infarction: a direct mechanism?

SGLT2 inhibitors have been developed as a novel class of glucose-lowering drugs affecting reabsorption of glucose and metabolic processes. They have been recently identified to be remarkably favorable in treating cardiovascular diseases, especially heart failure. Preclinical experiments have shown that SGLT2 inhibitors could hinder the progression of myocardial infarction and alleviate cardiac remodeling by mechanisms of metabolism influence, autophagy induction, inflammation attenuation and fibrosis reduction. Here we summarize the direct mechanism of SGLT2 inhibitors on myocardial infarction and investigate whether it could be applied to the clinic in improving cardiac function and healing after myocardial infarction.

Glucose-Lowering and Metabolic Effects of SGLT2 Inhibitors

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have consistently demonstrated improved outcomes in patients with heart failure with or without type 2 diabetes; however, the mechanisms contributing to these benefits remain poorly understood. Although SGLT2 inhibitors do have glucose-lowering effects, it is unlikely that their cardiovascular benefits are solely due to improved glycemic control. This improved glycemia leads to consequent metabolic effects that could provide further explanation for their action. This review discusses the glucose-lowering and metabolic effects of SGLT2 inhibitors and how these might lead to improved cardiovascular outcomes in patients with heart failure.

Meta-analysis of the effect of sodium-dependent glucose transporter 2 inhibitors on C-reactive protein in type 2 diabetes

BACKGROUND

As novel hypoglycemic drugs, the effects of sodium-dependent glucose transporter 2 inhibitors (SGLT-2I) on inflammatory factors such as C-reactive protein (CRP) remain unclear.

METHODS

We conducted a meta-analysis of studies on SGLT-2I in the treatment of type 2 diabetes (T2DM) to observe the changes of CRP in patients with T2DM. We searched 4 electronic databases (CNKI, PubMed, EMBASE, and Cochrane Library) for articles published up to December 31, 2021. Studies were analyzed using a random-effects model to obtain standard deviation mean differences (SMDs) and 95% confidence intervals (CIs). Sensitivity and subgroup analyses were performed. Publication bias was evaluated using funnel plots and Egger test.

RESULTS

We included data from 927 patients in 13 confirmatory trials that showed a significant decrease in CRP among patients with T2DM treated with SGLT-2I. The decrease was more significant with than without SGLT-2I. In subgroup analysis according to nationality, medication, and comorbidities, CRP reduction was associated with nationality, SGLT-2I type, and the presence of comorbidities. Sensitivity analysis showed that our results were reliable and found no evidence of substantial publication bias.

CONCLUSIONS

SGLT-2I could reduce CRP levels in patients with T2DM.

REGISTRATION

International Prospective Register for Systematic Reviews (PROSPERO) number CRD42021268079.

SGLT2 inhibitor dapagliflozin reduces endothelial dysfunction and microvascular damage during cardiac ischemia/reperfusion injury through normalizing the XO-SERCA2-CaMKII-coffilin pathways

Background: Given the importance of microvascular injury in infarct formation and expansion, development of therapeutic strategies for microvascular protection against myocardial ischemia/reperfusion injury (IRI) is of great interest. Here, we explored the molecular mechanisms underlying the protective effects of the SGLT2 inhibitor dapagliflozin (DAPA) against cardiac microvascular dysfunction mediated by IRI. Methods: DAPA effects were evaluated both in vivo, in mice subjected to IRI, and in vitro, in human coronary artery endothelial cells (HCAECs) exposed to hypoxia/reoxygenation (H/R). DAPA pretreatment attenuated luminal stenosis, endothelial swelling, and inflammation in cardiac microvessels of IRI-treated mice. Results: In H/R-challenged HCAECs, DAPA treatment improved endothelial barrier function, endothelial nitric oxide synthase (eNOS) activity, and angiogenic capacity, and inhibited H/R-induced apoptosis by preventing cofilin-dependent F-actin depolymerization and cytoskeletal degradation. Inhibition of H/R-induced xanthine oxidase (XO) activation and upregulation, sarco(endo)plasmic reticulum calcium-ATPase 2 (SERCA2) oxidation and inactivation, and cytoplasmic calcium overload was further observed in DAPA-treated HCAECs. DAPA also suppressed calcium/Calmodulin (CaM)-dependent kinase II (CaMKII) activation and cofilin phosphorylation, and preserved cytoskeleton integrity and endothelial cell viability following H/R. Importantly, the beneficial effects of DAPA on cardiac microvascular integrity and endothelial cell survival were largely prevented in IRI-treated SERCA2-knockout mice. Conclusions: These results indicate that DAPA effectively reduces cardiac microvascular damage and endothelial dysfunction during IRI through inhibition of the XO-SERCA2-CaMKII-cofilin pathway.

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.

Effects of dapagliflozin in the progression of atherosclerosis in patients with type 2 diabetes: a meta-analysis of randomized controlled trials

AIMS

At present, an increasing number of studies are trying to determine whether dapagliflozin has a significant effect on the occurrence and development of atherosclerosis in patients with type 2 diabetes mellitus (T2DM), but there is no consensus. In addition, the former meta-analyses, relying on only a few previous studies and a minimal number of research indicators, have not been able to draw sufficient conclusions simultaneously. Consequently, we conducted a meta-analysis to evaluate the effectiveness of dapagliflozin in the occurrence and development of atherosclerosis in patients with T2DM.

METHODS

We searched electronic databases (PubMed, Embase, Cochrane, and Scopus) and reference lists in relevant papers for articles published in 2011-2021. We selected studies that evaluated the effects of dapagliflozin on the risk factors related to the occurrence or development of atherosclerosis in patients with T2DM. A fixed or random-effect model calculated the weighted average difference of dapagliflozin on efficacy, and the factors affecting heterogeneity were determined by Meta-regression analysis.

RESULTS

Twelve randomized controlled trials (18,758 patients) were incorporated in our meta-analysis. In contrast with placebo, dapagliflozin was associated with a significantly increase in high density lipoprotein-cholesterol (HDL-C) [MD = 1.39; 95% CI (0.77, 2.01); P < 0.0001], Δflow-mediated vasodilatation (ΔFMD) [MD = 1.22; 95% CI (0.38, 2.06); P = 0.005] and estimated Glomerular Filtration Rate(eGFR) [MD = 1.94; 95% CI (1.38, 2.51); P < 0.00001]. Furthermore, dapagliflozin had a tremendous advantage in controlling triglycerides (TG) in subgroups whose baseline eGFR < 83 ml/min/1.73m2 [MD = - 10.38; 95% CI (- 13.15, - 7.60); P < 0.00001], systolic blood pressure (SBP) [MD = - 2.82; 95% CI (- 3.22, - 2.42); P < 0.00001], HbA1c, BMI, body weight and waist circumference. However, dapagliflozin has an adverse effect on increasing total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C). Besides, there were no significant changes in other indicators, including adiponectin and C-peptide immunoreactivity.

CONCLUSIONS

Our pooled analysis suggested that dapagliflozin has a terrifically better influence over HDL-C, ΔFMD, and eGFR, and it concurrently had a tremendous advantage in controlling TG, SBP, DBP, HbA1c, BMI, body weight, and waist circumference, but it also harms increasing TC and LDL-C. Furthermore, this study found that the effect of dapagliflozin that decreases plasma levels of TG is only apparent in subgroups of baseline eGFR < 83 ml/min/1.73m2, while the subgroup of baseline eGFR ≥ 83 ml/min/1.73m2 does not. Finally, the above results summarize that dapagliflozin could be a therapeutic option for the progression of atherosclerosis in patients with T2DM. Systematic review registration PROSPERO CRD42021278939.

Effects of Antidiabetic Drugs on Endothelial Function in Patients With Type 2 Diabetes Mellitus: A Bayesian Network Meta-Analysis

BACKGROUND

The changes of endothelial function in type 2 diabetes mellitus (T2DM) patients are closely associated with the development of cardiovascular disease (CVD). However, it is still unclear whether commonly used antidiabetic drugs can improve endothelial function. Flow-mediated dilation (FMD) is a noninvasive tool for evaluating endothelial function, which typically examines changes in the brachial artery diameter in response to ischemia using ultrasound. We performed a network meta-analysis (NMA) to explore the associations between changes in endothelial function and antidiabetic drugs by evaluating FMD in T2DM patients.

METHODS

We systematically searched several electronic databases for randomized controlled trials (RCTs) published from inception until January 25, 2022 with no language restriction. The primary outcome was FMD change in all studies, and we performed subgroup analysis in T2DM patients without CVD. NMA was performed to calculate the mean differences (MDs) with 95% confidence intervals (CIs).

RESULTS

From the 1,987 candidate articles identified in the initial search, 30 RCTs were eventually included in the analysis. In all studies, glucagon-like peptide-1 receptor (GLP-1R) agonists [MD = 3.70 (1.39-5.97)], TZD [MD = 1.96 (0.006-3.89)] produced improvement of FMD change compared to lifestyle intervention. GLP-1R agonists [MD = 3.33 (1.36-5.34) and MD = 3.30 (1.21-5.43)] showed significantly greater improvements in FMD change in pairwise comparisons with sulfonylureas and placebo. SGLT-2i also showed efficacy compared to sulfonylureas (MD = 1.89, 95% CI, 0.10, 3.75). In studies of T2DM patients without CVD, GLP-1R agonists [MD = 3.53 (1.24-5.76)], and TZD [MD = 2.30 (0.27-3.24)] produced improvements in FMD change compared to lifestyle treatment. GLP-1R agonists [MD = 3.25 (1.13-5.40), and MD = 3.85 (1.68-6.13)] showed significantly greater improvements in pairwise comparisons with sulfonylureas, and placebo.

CONCLUSION

In T2DM patients, both GLP-1R agonists, SGLT-2i and TZD have favorable effects to improve endothelial function in T2DM patients. In T2DM patients without CVD, GLP-1R agonists had a greater effect to improve endothelial function than sulfonylureas. These suggested that GLP-1R agonists are associated with significantly improved endothelial function in T2DM patients.

Effects of SGLT-2 Inhibitors on Vascular Endothelial Function and Arterial Stiffness in Subjects With Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the effects of SGLT-2 inhibitors (SGLT-2i) on endothelial function and arteriosclerosis in diabetic patients.

METHODS

Randomized controlled trials (RCTs) were retrieved from PubMed, Embase, Cochrane Library, and Web of Science databases to evaluate the effects of SGLT-2i on endothelial function and atherosclerosis in type 2 diabetic patients.

RESULTS

We selected 9 RCTs and 2 cohort studys involving 868 patients. Of these, six studies provided flow-mediated dilation (FMD) levels before and after the intervention. The pooled analysis showed that SGLT-2i could significantly improve the FMD compared to the control group (SMD: 0.18, 95% CI: 0.02 ~ 0.34, P = 0.03). Three studies provided the change in FMD before and after the intervention. Pooled analysis showed no significant differences in FMD change between the SGLT-2i group and the control group. (MD: 2.1, 95%-CI: -0.11~4.31, P = 0.06). Five studies showed pulse wave velocity (PWV) results. Pooled analysis showed no significant differences in the change in PWV between the SGLT-2i group and the control group (SMD: 0.11, 95%-CI: - 0.15 ~ 0.37, P = 0.4).

CONCLUSIONS

The ability of SGLT-2 inhibitors to improve FMD was significant, but there was no significant effect on PWV levels. SGLT-2i was superior to other antidiabetic agents in improving arterial endothelial function.

Effect of glycemic control on markers of subclinical atherosclerosis in patients with type 2 diabetes mellitus: A review

Cardiovascular disease is the predominant cause of death in type 2 diabetes mellitus (T2DM). Evidence suggests a strong association between duration and degree of hyperglycemia and vascular disease. However, large trials failed to show cardiovascular benefit after intensive glycemic control, especially in patients with longer diabetes duration. Atherosclerosis is a chronic and progressive disease, with a long asymptomatic phase. Subclinical atherosclerosis, which is impaired in T2DM, includes impaired vasodilation, increased coronary artery calcification (CAC), carotid intima media thickness, arterial stiffness, and reduced arterial elasticity. Each of these alterations is represented by a marker of subclinical atherosclerosis, offering a cost-effective alternative compared to classic cardiac imaging. Their additional use on top of traditional risk assessment strengthens the predictive risk for developing coronary artery disease (CAD). We, herein, review the existing literature on the effect of glycemic control on each of these markers separately. Effective glycemic control, especially in earlier stages of the disease, attenuates progression of structural markers like intima-media thickness and CAC. Functional markers are improved after use of newer anti-diabetic agents, such as incretin-based treatments or sodium-glucose co-transporter-2 inhibitors, especially in T2DM patients with shorter disease duration. Larger prospective trials are needed to enhance causal inferences of glycemic control on clinical endpoints of CAD.

Sodium-glucose cotransporter 2 inhibitor effects on heart failure hospitalization and cardiac function: systematic review

AIMS

To systematically review randomized controlled trials assessing effects of sodium-glucose cotransporter 2 inhibitors (SGLT2is) on hospitalization for heart failure (HHF) and cardiac structure/function and explore randomized controlled trial (RCT)-derived evidence for SGLT2i efficacy mechanisms in heart failure (HF).

METHODS AND RESULTS

Systematic searches of Medline and Embase were performed. In seven trials [3730-17 160 patients; low risk of bias (RoB)], SGLT2is significantly reduced the relative risk of HHF by 27-39% vs. placebo, including in two studies in patients with HF with reduced ejection fraction with or without type-2 diabetes mellitus (T2DM). Improvements in conventional cardiovascular risk factors, including glycaemic levels, cannot account for these effects. Five trials (56-105 patients; low RoB) assessed the effects of 6-12 months of SGLT2i treatment on left ventricular structure/function; four reported significant improvements vs. placebo, and one did not. Five trials (low RoB) assessed SGLT2i treatment effects on serum N-terminal pro B-type natriuretic peptide levels; significant reductions vs. placebo were reported after 8-12 months (two studies; 3730-4744 patients) but not ≤12 weeks (three studies; 80-263 patients). Limited available RCT-derived evidence suggests various possible cardioprotective SGLT2i mechanisms, including improved haemodynamics (natriuresis and reduced interstitial fluid without blood volume contraction/neurohormonal activation) and vascular function, enhanced erythropoiesis, reduced tissue sodium and epicardial fat/inflammation, decreased sympathetic tone, and beneficial changes in cellular energetics.

CONCLUSIONS

Sodium-glucose cotransporter 2 inhibitors reduce HHF regardless of T2DM status, and reversal of adverse left ventricular remodelling likely contributes to this efficacy. Hypothesis-driven mechanistic trials remain sparse, although numerous trials are planned or ongoing.

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.

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

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

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

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

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

Background

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

Impact of glycemic control on the association of endothelial dysfunction and coronary artery disease in patients with type 2 diabetes mellitus

Background

We investigated whether glycemic control affects the relation between endothelial dysfunction and coronary artery disease in patients with type 2 diabetes mellitus (T2DM).

Methods

In 102 type 2 diabetic patients with stable angina, endothelial function was evaluated using brachial artery flow-mediated dilation (FMD) with high-resolution ultrasound, and significant stenosis of major epicardial coronary arteries (≥ 50% diameter narrowing) and degree of coronary atherosclerosis (Gensini score and SYNTAX score) were determined. The status of glycemic control was assessed by blood concentration of glycated hemoglobin (HbA1c).

Results

The prevalence of significant coronary artery stenosis (67.9% vs. 37.0%, P = 0.002) and degree of coronary atherosclerosis (Gensini score: 48.99 ± 48.88 vs. 15.07 ± 21.03, P < 0.001; SYNTAX score: 15.88 ± 16.36 vs. 7.28 ± 10.54, P = 0.003) were higher and FMD was lower (6.03 ± 2.08% vs. 6.94 ± 2.20%, P = 0.036) in diabetic patients with poor glycemic control (HbA1c ≥ 7.0%; n = 56) compared to those with good glycemic control (HbA1c < 7.0%; n = 46). Multivariate regression analysis revealed that tertile of FMD was an independent determinant of presence of significant coronary artery stenosis (OR = 0.227 95% CI 0.056–0.915, P = 0.037), Gensini score (β =  − 0.470, P < 0.001) and SYNTAX score (β =  − 0.349, P = 0.004) in diabetic patients with poor glycemic control but not for those with good glycemic control (P > 0.05).

Conclusion

Poor glycemic control negatively influences the association of endothelial dysfunction and coronary artery disease in T2DM patients.

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

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

Anti-inflammatory properties of antidiabetic drugs: A "promised land" in the COVID-19 era?

Inflammation is implicated in the development and severity of the coronavirus disease 2019 (COVID-19), as well as in the pathophysiology of diabetes. Diabetes, especially when uncontrolled, is also recognized as an important risk factor for COVID-19 morbidity and mortality. Furthermore, certain inflammatory markers [i.e. C-reactive protein (CRP), interleukin-6 (IL-6) and ferritin] were reported as strong predictors of worse outcomes in COVID-19 positive patients. The same biomarkers have been associated with poor glycemic control. Therefore, achieving euglycemia in patients with diabetes is even more important in the era of the COVID-19 pandemic. Based on the above, it is clinically interesting to elucidate whether antidiabetic drugs may reduce inflammation, thus possibly minimizing the risk for COVID-19 development and severity. The present narrative review discusses the potential anti-inflammatory properties of certain antidiabetic drugs (i.e. metformin, pioglitazone, sitagliptin, linagliptin, vildagliptin, alogliptin, saxagliptin, liraglutide, dulaglutide, exenatide, lixisenatide, semaglutide, empagliflozin, dapagliflozin, canagliflozin), with a focus on CRP, IL-6 and ferritin.

Effect of Sodium-Glucose Cotransporter-2 Inhibitors on Endothelial Function: A Systematic Review of Preclinical Studies

INTRODUCTION

While the beneficial effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on cardiovascular and renal outcomes are recognized, their direct effects on endothelial function remain unclear. We, therefore, undertook a systematic review to evaluate the current literature in this area.

METHODS

Electronic databases (PubMed, EMBASE, and Medline) were systematically searched using PRISMA guidelines for studies involving the in vitro, in vivo, or ex vivo administration of SGLT-2 inhibitors to animals, vascular tissue, or vascular endothelial cells.

RESULTS

Of 144 retrieved publications, 24 experimental studies met the inclusion criteria. Reporting of possible sources of bias were poor, making the overall risk of bias difficult to assess. Within the 24 studies, the SGLT-2 inhibitors canagliflozin, ipragliflozin, empagliflozin, dapagliflozin, tofogliflozin, and luseogliflozin were assessed as interventions. Animal model studies (n = 17) demonstrated that all SGLT-2 inhibitors prevented endothelial dysfunction and enhanced endothelium-dependent vasorelaxation in diabetic and non-diabetic models. In vitro studies (n = 9) using human endothelial cells indicated a direct anti-inflammatory effect of dapagliflozin (1-100 nM) and canagliflozin, (10 µM), while empagliflozin (1 and 10 µM) improved viability of hyperglycemic cells. Potential mechanisms of action of the SGLT-2 inhibitors include a reduction in oxidative stress, modulation of adhesion molecules and reductions in pro-inflammatory cytokines.

CONCLUSIONS

Preclinical studies indicate that SGLT-2 inhibitors attenuate vascular dysfunction in preclinical models via a combination of mechanisms that appear to act independently of glucose-lowering benefits.

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

Background

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

Methods

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

Discussion

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

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