SGLT2 inhibitors reduce infarct size in reperfused ischemic heart and improve cardiac function during ischemic episodes in preclinical models

Sodium-glucose cotransporter-2 inhibitors in individuals with ischemia reperfusion injury: A systematic review

Background: The effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on ischemia reperfusion injury (IRI) is a novel concept and only limited number of animals studies have yet been investigated. We aimed to perform a systematic review of literature to explore the clinical studies which investigated the effects of SGLT-2 inhibitors on myocardial IRI setting.Methods: We searched MEDLINE, Embase, and Cochrane Library from inception until December 7th, 2023. ClinicalTrials.gov was also explored for ongoing studies. Two authors independently conducted the literature search, examined the studies, and evaluated the eligibility criteria. Any disagreements or uncertainties were resolved by the corresponding author. The search strategy followed the PICO process (Population, Intervention, Comparison, and Outcome) and Emtree was used to select relevant keywords.Results: Of 220 articles identified from the literature research, five articles were included in the study, of which three studies lately were retracted. The remaining studies included 1229 participants, with 209 receiving SGLT-2 inhibitors and 1090 not receiving them. All of the participants were diabetic patients admitted with acute myocardial infarction (AMI), undergoing percutaneous coronary intervention (PCI). The results demonstrated that the use of SGLT-2 inhibitors is associated with lower troponin levels, and higher rates of ST resolution. The results of the studies also showed smaller infarct sizes, lower inflammatory biomarkers and improved left ventricular function at discharge among SGLT-2 inhibitor users.Conclusion: In line with in vivo and ex vivo findings, the results of this systematic review supported benefits of SGLT-2 inhibitors in IRI through reducing infarct size and inflammatory biomarkers. However, further clinical trials are warranted to provide robust evidence.

Impact of sodium-glucose cotransporter-2 inhibitors on heart failure outcomes in cancer patients and survivors: a systematic review and meta-analysis

AIMS

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are recognized for their cardiovascular benefits. This systematic review and meta-analysis evaluated the impact of SGLT2i on heart failure (HF) outcomes in cancer patients and survivors, focusing on HF hospitalization and new HF diagnoses.

METHODS AND RESULTS

A comprehensive search of PubMed, MEDLINE, and Embase via Ovid, and the Cochrane Library was conducted up to 5 June 2024, focusing on studies involving cancer patients and survivors treated with SGLT2i. The search criterion used was [(SGLT2) OR (Sodium glucose cotransporter 2 inhibitors) OR (canagliflozin) OR (dapagliflozin) OR (empagliflozin) OR (ertugliflozin) AND (cancer)]. The primary outcomes assessed were HF hospitalization and new HF diagnoses. The search yielded 1880 studies, from which 13 studies encompassing 88 273 patients were included. SGLT2i use reduced HF hospitalizations by 51% (RR 0.49, 95% CI 0.36-0.66, I² = 28%, P < 0.01) and new HF diagnoses by 71% (RR 0.29, 95% CI 0.10-0.87, I² = 71%). Multi-variate meta-regression analysis suggested that among breast cancer populations, studies with ≥50% of patients on anthracyclines exhibited a 99% reduction in HF hospitalization risk compared with similar studies that included <50% of patients on anthracyclines (RR 0.0085, 95% CI: 0.0001-0.2645, P = 0.0081).

CONCLUSION

SGLT2i significantly lower the risk of HF hospitalization and new HF diagnoses among cancer patients and survivors, with particularly pronounced benefits in breast cancer patients receiving anthracycline-based chemotherapy. These findings support the need for prospective trials to further investigate the integration of SGLT2i into cancer patient management to enhance cardiovascular outcomes.

Sodium-glucose cotransporter 2 inhibitors in patients with type 2 diabetes and myocardial infarction undergoing percutaneous coronary intervention: A systematic review and meta-analysis

Background

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have shown benefits in improving cardiovascular (CV) outcomes in patients with heart failure (HF) and may mitigate symptom progression in myocardial infarction (MI). However, their effectiveness in patients with type 2 diabetes and MI undergoing percutaneous coronary intervention (PCI) is unclear.

Methods

To identify eligible studies, a comprehensive search of electronic databases, PubMed, Cochrane Library, Scopus and Embase, was conducted from inception until May 2024. Results were presented as risk ratios (RR) and their corresponding 95 % confidence intervals (CIs).

Results

Our analysis included 8 observational studies comprising 24,229 patients. The results indicated that SGLT2i with PCI was associated with a significantly reduced risk of all-cause death (RR=0.61; 95 % CI=0.54 to 0.68), CV death (RR=0.46; 95 % CI=0.22 to 0.94), major adverse cardiovascular events (RR=0.80;95 % CI: 0.66 to 0.96), HF-related hospitalizations (RR=0.63; 95 % CI=0.44 to 0.90), stroke (RR=0.77; 95 % CI: 0.62 to 0.96) and acute kidney injury (RR=0.46; 95 % CI: 0.25 to 0.84) compared to PCI without SGLT2i use. However, the risk of revascularization remained comparable between the groups.

Conclusion

Our study demonstrates that SGLT2i with PCI in patients with type 2 diabetes and MI are associated with improved CV outcomes compared to PCI without SGLT2i use. Randomized controlled trials are required to confirm the improvement in outcomes with SGLT2i therapy combined with PCI in patients with MI and diabetes.

Effects of sodium-glucose cotransporter-2 inhibitors in myocardial infarction patients: A systematic review and meta-analysis

AIMS

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are known to improve cardiovascular outcomes in individuals with heart failure (HF), type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD). However, their efficacy following myocardial infarction (MI) remains unclear.

MATERIALS AND METHODS

A systematic search was conducted using PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov. Primary outcomes included hospitalization for heart failure (HHF), cardiovascular (CV) death, a composite of HHF or CV death, all-cause death, major cardiovascular events (MACE), recurrent MI, severe arrhythmia, renal injury and stroke. Secondary outcomes targeted improvements in left ventricular ejection fraction (LVEF) and left ventricular end-diastolic volume (LVEDV).

RESULTS

Thirteen studies comprising 22 370 patients were included. Meta-analysis revealed that SGLT2 inhibitors reduced HHF (RR 0.69, 95% CI 0.61 to 0.78, p < 0.001), combined HHF or CV death (RR 0.87, 95% CI 0.77 to 0.99, p = 0.028), all-cause mortality (RR 0.82, 95% CI 0.73 to 0.93, p = 0.002), MACE (RR 0.68, 95% CI 0.53 to 0.88, p = 0.004), recurrent MI (RR 0.81, 95% CI 0.69 to 0.94, p = 0.007), severe arrhythmia (RR 0.54, 95% CI 0.34 to 0.85, p = 0.009) and renal injury (RR 0.68, 95% CI 0.53 to 0.87, p = 0.002). Improvement in LVEF (MD 3.96%, 95% CI 2.52 to 5.40; p < 0.001) and LVEDV (MD -5.52 mL, 95% CI -10.21 to -0.83; p = 0.021) was notably greater in the SGLT2 inhibitors group.

CONCLUSIONS

In post-MI patients, we first found that SGLT2 inhibitors significantly lowered the risk of HHF, combined CV death or HHF, all-cause death, MACE, recurrent MI, severe arrhythmias and renal injury. Additionally, SGLT2 inhibitors improved LVEF and LVEDV.

AlBarakat M, Elewidi M, Abuelazm M, Turkmani M, Abdelazeem B, Laeeq R. The effect of sodium-glucose co-transporter 2 inhibitors on clinical outcomes after acute myocardial infarction: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Sodium-glucose cotransporter 2 inhibitors (SGLT2is) reduce cardiovascular events, especially in diabetic patients. However, the cardioprotective effects of early SGLT2i administration following acute myocardial infarction (AMI) remain unclear.

OBJECTIVE

This study aims to investigate the impact of SGLT2is on clinical outcomes in patients post-AMI.

METHODS

A comprehensive search was conducted in PubMed, CENTRAL, WOS, Scopus, and EMBASE up to April 2024. Risk ratio (RR) was used for dichotomous outcomes and mean difference (MD) for continuous outcomes, with 95% confidence intervals (CI).

RESULTS

Seven studies with 11,407 patients were included. SGLT2is did not significantly reduce the incidence of major adverse cardiovascular events (MACE) (RR = 0.94, 95% CI [0.68, 1.29], p = 0.69), all-cause mortality (RR = 1.01, 95% CI [0.84, 1.21], p = 0.93), or stroke (RR = 0.61, 95% CI [0.29,1.28], p = 0.19). However, SGLT2is significantly reduced the risk of heart failure (RR = 0.76, 95% CI [0.63, 0.91], p < 0.01) and improved left ventricular ejection fraction (MD = 1.86, 95% CI [1.58, 2.14], p < 0.01).

CONCLUSION

In post-AMI patients, SGLT2is do not significantly affect MACE or mortality but are associated with reduced heart failure risk and improved ejection fraction.

PROTOCOL REGISTRATION

PROSPERO identifier number: CRD42024506806.

The Effect of Dapagliflozin on Heart Function in Animal Models of Cardiac Ischemia, A Systematic Review and Meta-analysis

INTRODUCTION

In this study, a meta-analysis was conducted to investigate the therapeutic effect of Dapagliflozin (DAPA) on animals suffering from myocardial ischemia reperfusion compared to the group that did not receive treatment.

METHODS

According to the inclusion and exclusion criteria two researchers performed the primary and secondary screening based on the title abstract and full text. After data extraction, meta-analysis was performed using STATA software. Standardized mean differences were used to analyze the results of the reported studies. Subgroup analysis and quality control of articles were also conducted.

RESULTS

A total of 21 separate experiments showed that DAPA increased mean fractional shortening (%FS) and ejection fraction (%EF) compared to the untreated animals. A significant reduction in the weight and size of the infarcted area and significant increases in dp/dt+, dp/dt-, left ventricular end-systolic internal dimensions (LVIDs), left ventricular end-diastolic internal dimensions (LVIDd), Volume systole and Volume diastole were observed in treated animals.

CONCLUSION

DAPA has the potential to become a candidate for the treatment of post-ischemic heart damage, pending animal and human studies to validate this.

Empagliflozin in Acute Myocardial Infarction Reduces No-Reflow and Preserves Cardiac Function by Preventing Endothelial Damage

Empagliflozin treatment before acute myocardial infarction mainly targets the endothelial cell transcriptome. Empagliflozin treatment before and after myocardial infarction decreased no reflow and microvascular injury, leading to reduced infiltration of inflammatory cells, reduced infarct size, and improved cardiac function in mice. In diabetic patients receiving empagliflozin after myocardial infarction, perfused boundary region, flow-mediated dilation, and global longitudinal strain were improved.

Sodium-Glucose Cotransporter 2 Inhibitor Therapy in Different Scenarios of Heart Failure: An Overview of the Current Literature

Heart failure (HF) is a complex syndrome that requires tailored and patient-centered treatment. Sodium-glucose cotransporter 2 inhibitors (SGLT2is) constitute one of the four pillars of the medical treatment of HF. However, the 2023 ESC guidelines treat HF as a single entity without making clear distinctions in phenotypes according to etiology. This creates a "gap in knowledge", causing much debate about the applicability of these drugs in peculiar clinical settings that are etiological and/or predisposing clinical conditions for HF. Furthermore, considering the variety of etiologies and different pathophysiological backgrounds of HF, one might question whether the use of SGLT2is is equally beneficial in all types of HF and whether certain drug-related properties may be exploited in different contexts. For example, SGLT2is can improve the metabolic and inflammatory state, which is fundamental in ischemic heart disease. Anti-inflammatory power can also play a paramount role in myocarditis or cardiotoxicity, while improving the congestive state and reducing filling pressure may be even more fundamental in restrictive heart disease or advanced heart disease. This review aims to gather the evidence currently present in the literature concerning the advantages or the disadvantages of using these drugs in these particular clinical settings, with the goal being an optimized and highly personalized treatment for HF.

The effect of Empagliflozin on echocardiographic parameters in diabetic patients after acute myocardial infarction: A systematic review and meta-analysis with trial sequential analysis

Patients with diabetes mellitus (DM) are at higher risk of cardiovascular events, particularly acute myocardial infarction (MI). Sodium-glucose cotransporter 2 inhibitors (SGLT2i) can improve cardiac outcomes among heart failure individuals, however, the effects on acute myocardial infarction remain unclear. This meta-analysis investigates the impact of empagliflozin in diabetic patients following acute myocardial infarction. We comprehensively searched PubMed, Scopus, Cochrane, and Web of Science through August 10th, 2023. We included studies comparing empagliflozin versus placebo in diabetes patients with acute myocardial infarction. We used Revman to report the data as mean difference (MD) and 95% confidence interval (CI), and our effect size with a random effects model. Additionally, we performed Trial Sequential Analysis (TSA) to test the robustness of the results. The study protocol was published on PROSPERO with ID: CRD42023447733. Five studies with a total of 751 patients were included in our analysis. Empagliflozin was effective to improve LVEF% (MD: 1.80, 95% CI [0.50, 3.10], p = 0.007), left ventricular end-diastolic volume (LVEDV) (MD: -9.93, 95% CI [-16.07, -3.80], p = 0.002), and left ventricular end-systolic volume (LVESV) (MD: -7.91, 95% CI [-11.93, -3.88], p = 0.0001). However, there was no difference between empagliflozin and placebo groups in terms of NT-pro BNP (MD: - 136.59, 95% CI [-293.43, 20.25], p = 0.09), and HbA1c (MD: -0.72, 95% CI [-1.73, 0.29], p = 0.16). Additionally, empagliflozin did not prevent hospitalization due to heart failure (RR: 0.59, 95% CI [0.16, 2.24], p = 0.44, I-squared = 0%), and mortality (RR: 1.34, 95% CI [0.15,11.90], p = 0.79, I-squared = 25%). Empagliflozin initiation in diabetic patients following acute MI may improve echocardiographic parameters. However, empagliflozin might not be effective in heart failure prevention and optimal glycemic control in this patient population. Further large-scale trials are warranted to ascertain our findings.

SGLT1 contributes to glucose-mediated exacerbation of ischemia-reperfusion injury in ex vivo rat heart

Hyperglycaemia is common during acute coronary syndromes (ACS) irrespective of diabetic status and portends excess infarct size and mortality, but the mechanisms underlying this effect are poorly understood. We hypothesized that sodium/glucose linked transporter-1 (SGLT1) might contribute to the effect of high-glucose during ACS and examined this using an ex-vivo rodent heart model of ischaemia-reperfusion injury. Langendorff-perfused rat hearts were subjected to 35 min ischemia and 2 h reperfusion, with variable glucose and reciprocal mannitol given during reperfusion in the presence of pharmacological inhibitors of SGLT1. Myocardial SGLT1 expression was determined in rat by rtPCR, RNAscope and immunohistochemistry, as well as in human by single-cell transcriptomic analysis. High glucose in non-diabetic rat heart exacerbated reperfusion injury, significantly increasing infarct size from 45 ± 3 to 65 ± 4% at 11-22 mmol/L glucose, respectively (p < 0.01), an association absent in diabetic heart (32 ± 1-37 ± 5%, p = NS). Rat heart expressed SGLT1 RNA and protein in vascular endothelium and cardiomyocytes, with similar expression found in human myocardium by single-nucleus RNA-sequencing. Rat SGLT1 expression was significantly reduced in diabetic versus non-diabetic heart (0.608 ± 0.08 compared with 1.116 ± 0.13 probe/nuclei, p < 0.01). Pharmacological inhibitors phlorizin, canagliflozin or mizagliflozoin in non-diabetic heart revealed that blockade of SGLT1 but not SGLT2, abrogated glucose-mediated excess reperfusion injury. Elevated glucose is injurious to the rat heart during reperfusion, exacerbating myocardial infarction in non-diabetic heart, whereas the diabetic heart is resistant to raised glucose, a finding which may be explained by lower myocardial SGLT1 expression. SGLT1 is expressed in vascular endothelium and cardiomyocytes and inhibiting SGLT1 abrogates excess glucose-mediated infarction. These data highlight SGLT1 as a potential clinical translational target to improve morbidity/mortality outcomes in hyperglycemic ACS patients.

Effects of dapagliflozin on myoglobin efflux from cardiomyocyte during myocardial ischemia/reperfusion in anesthetized rats

It has been suggested that sodium-glucose cotransporter 2 (SGLT2) inhibitors have cardioprotective effects during myocardial ischemia/reperfusion (I/R) independent of glucose-lowering action. However, the effects of SGLT2 inhibitors on structural damage to cardiomyocytes in the ischemic region during I/R remain unknown. We applied a microdialysis technique to the heart of anesthetized rats and investigated the effects of an SGLT2 inhibitor, dapagliflozin, on myocardial interstitial myoglobin levels in the ischemic region during coronary occlusion followed by reperfusion. Dapagliflozin was administered systemically (40 μg/body iv) or locally via a dialysis probe (100 μM and 1 mM) 30 min before coronary occlusion. In the vehicle group, coronary occlusion increased the dialysate myoglobin concentration in the ischemic region. Reperfusion further increased the dialysate myoglobin concentration. Intravenous administration of dapagliflozin reduced dialysate myoglobin concentration during ischemia and at 0-15 min after reperfusion, but local administration (100 μM and 1 mM) did not. Therefore, acute systemic administration of dapagliflozin prior to ischemia has cardioprotective effects on structural damage during I/R.

The Off-Target Cardioprotective Mechanisms of Sodium-Glucose Cotransporter 2 Inhibitors: An Overview

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), a novel class of glucose-lowering drugs, have revolutionized the management of heart failure with reduced and preserved ejection fraction, regardless of the presence of diabetes, and are currently incorporated in the heart failure guidelines. While these drugs have consistently demonstrated their ability to decrease heart failure hospitalizations in several landmark clinical trials, their cardioprotective effects are far from having been completely elucidated. In the past decade, a growing body of experimental research has sought to address the molecular and cellular mechanisms of SGLT2i in order to provide a better understanding of the off-target acute and chronic cardiac benefits, beyond the on-target renal effect responsible for blood glucose reduction. The present narrative review addresses the direct cardioprotective effects of SGLT2i, delving into the off-target mechanisms of the drugs currently approved for heart failure therapy, and provides insights into future perspectives.

Sodium-glucose cotransporter-2 inhibitors: a swinging pendulum in the treatment of acute myocardial infarction

INTRODUCTION

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are integral in treating patients with heart failure, regardless of the existence of diabetes mellitus. In light of their benefits on the heart muscle, the question of their effect on acute coronary syndrome is raised, and a hypothesis as to whether they can be implemented in its treatment is proposed. The aim of the article was to indicate the potential of using SGLT2 inhibitors in the treatment of myocardial infarction (MI).

EVIDENCE ACQUISITION

A PubMed search for articles published between October 2017 and May 2022 was conducted using the following keywords: "SGLT2 inhibitors," "Acute Coronary Syndrome," "Treatment," "Prognosis." Reference lists of identified articles were searched for further articles.

EVIDENCE SYNTHESIS

Reports from clinical trials and animal studies thus far investigating mechanistic pathways of SGLT2 inhibitors' effect in relation to acute myocardial infarction were interplayed to extract relevant findings and analyze the safety of this therapy in acute coronary syndrome (ACS) patients.

CONCLUSIONS

SGLT2 inhibitors indicate beneficial effects in acute cardiovascular incident by various mechanisms, and early initiation of therapy may improve outcomes for AMI survivors.

Cardioprotective Effects of Sodium-Glucose Cotransporter Subtype Inhibition on Ischemic and Pharmacological Preconditioning

BACKGROUND

Sodium-glucose cotransporter (SGLT) 2 inhibitors partially inhibit SGLT1 expression; however, whether a clinical dose of SGLT2 inhibitor abrogates ischemic preconditioning (IPC) is unknown, and the pharmacological cardioprotective effect under SGLT1 inhibition has not been examined. In this study, we investigated whether a clinical dose of tofogliflozin abrogates IPC and whether pharmacological preconditioning with olprinone has cardioprotective effects under SGLT1 inhibition.

METHODS

Male Wistar rats were divided into seven groups (seven rats per group) and subjected to the following treatments before inducing ischemia/reperfusion (I/R; 30 minutes of coronary artery occlusion followed by 120 minutes of reperfusion): saline infusion control treatment (Con); ischemic preconditioning (IPC); IPC after phlorizin infusion (IPC+Phl); IPC after low-dose tofogliflozin infusion (IPC+L-Tof); IPC after high-dose tofogliflozin infusion (IPC+H-Tof); olprinone infusion (Olp); and Olp infusion after phlorizin infusion (Olp+Phl).

RESULTS

The infarct size was significantly decreased in the IPC group, but not in the IPC+Phl group. In contrast, the infarct size decreased in the IPC+L-Tof and IPC+H-Tof groups. Additionally, Olp reduced the infarct size, and the effect was preserved in Olp+Phl groups. Phosphorylated AMP-activated protein kinase (AMPK) expression was lower in the IPC+Phl group compared to that in the IPC group.

CONCLUSION

The cardioprotective effect of IPC was attenuated by strong SGLT1 inhibition, but the effect was preserved under a clinical dose of highly selective SGLT2 inhibitor. Olprinone exerts a cardioprotective effect even under strong SGLT1 inhibition.

Targeting inflammatory signaling pathways with SGLT2 inhibitors: Insights into cardiovascular health and cardiac cell improvement

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have attracted significant attention for their broader therapeutic impact beyond simply controlling blood sugar levels, particularly in their ability to influence inflammatory pathways. This review delves into the anti-inflammatory properties of SGLT2 inhibitors, with a specific focus on canagliflozin, empagliflozin, and dapagliflozin. One of the key mechanisms through which SGLT2 inhibitors exert their anti-inflammatory effects is by activating AMP-activated protein kinase (AMPK), a crucial regulator of both cellular energy balance and inflammation. Activation of AMPK by these inhibitors leads to the suppression of pro-inflammatory pathways and a decrease in inflammatory mediators. Notably, SGLT2 inhibitors have demonstrated the ability to inhibit the release of cytokines in an AMPK-dependent manner, underscoring their direct influence on inflammatory signaling. Beyond AMPK activation, SGLT2 inhibitors also modulate several other inflammatory pathways, including the NLRP3 inflammasome, expression of Toll-like receptor 4 (TLR-4), and activation of NF-κB (Nuclear factor kappa B). This multifaceted approach contributes to their efficacy in reducing inflammation and managing associated complications in conditions such as diabetes and cardiovascular disorders. Several human and animal studies provide support for the anti-inflammatory effects of SGLT2 inhibitors, demonstrating protective effects on various cardiac cells. Additionally, these inhibitors exhibit direct anti-inflammatory effects by modulating immune cells. Overall, SGLT2 inhibitors emerge as promising therapeutic agents for targeting inflammation in a range of pathological conditions. Further research, particularly focusing on the molecular-level pathways of inflammation, is necessary to fully understand their mechanisms of action and optimize their therapeutic potential in inflammatory diseases.

Mesenchymal stromal cells for improvement of cardiac function following acute myocardial infarction: a matter of timing

Acute myocardial infarction (AMI) is the leading cause of cardiovascular death and remains the most common cause of heart failure. Reopening of the occluded artery, i.e., reperfusion, is the only way to save the myocardium. However, the expected benefits of reducing infarct size are disappointing due to the reperfusion paradox, which also induces specific cell death. These ischemia-reperfusion (I/R) lesions can account for up to 50% of final infarct size, a major determinant for both mortality and the risk of heart failure (morbidity). In this review, we provide a detailed description of the cell death and inflammation mechanisms as features of I/R injury and cardioprotective strategies such as ischemic postconditioning as well as their underlying mechanisms. Due to their biological properties, the use of mesenchymal stromal/stem cells (MSCs) has been considered a potential therapeutic approach in AMI. Despite promising results and evidence of safety in preclinical studies using MSCs, the effects reported in clinical trials are not conclusive and even inconsistent. These discrepancies were attributed to many parameters such as donor age, in vitro culture, and storage time as well as injection time window after AMI, which alter MSC therapeutic properties. In the context of AMI, future directions will be to generate MSCs with enhanced properties to limit cell death in myocardial tissue and thereby reduce infarct size and improve the healing phase to increase postinfarct myocardial performance.

Effect of 24 h glucose fluctuations on 30-day and 1-year mortality in patients with acute myocardial infarction: an analysis from the MIMIC-III database

Background

It is recognized that patients' blood glucose fluctuates over time during acute disease episodes, especially during the outbreak of cardiovascular events, regardless of the presence of an abnormal blood glucose profile prior to admission to the hospital. Glucose fluctuations in patients with acute myocardial infarction (AMI) in the intensive care unit (ICU) are currently not adequately monitored and studied. We focused on blood glucose fluctuation values within 24 h of admission to assess their association with 30-day and 1-year mortality.

Methods

Data of patients with AMI aged 18 years or older from the Critical Care Medical Information Marketplace database III V1.4 were available for analysis in this research. Glucose data were obtained by measurement. A total of 390 of them were treated with PCI. The principal consequence was 30-day and 1-year mortality in patients with AMI. The effect of different glucose fluctuations within 24 h of admission on mortality was predicted by constructing a multivariate Cox regression model with four model adjustments and Kaplan-Meier survival curves. Additionally, we performed curve-fitting analyses to show the correlation between blood glucose fluctuations and risk of death.

Results

We selected 1,699 AMI patients into our study through screening. The included population was categorized into three groups based on the tertiles of blood glucose fluctuation values within 24 h of admission to the ICU. The three groups were <25 mg/dl, 25-88 mg/dl and >88 mg/dl. By cox regression analysis, the group with the highest blood glucose fluctuation values (>88 mg/dl) had the most significant increase in 30-day and 1-year mortality after excluding confounding factors (30-day mortality adjusted HR = 2.11; 95% CI = 1.49-2.98 p < 0.001; 1-year mortality adjusted HR = 1.83; 95% CI = 1.40-2.39 p < 0.001). As demonstrated by the Kaplan-Meier survival curves, the group with the greatest fluctuations in blood glucose has the worst 30-day and 1-year prognosis.

Conclusions

The extent of glucose fluctuations in patients with AMI in the first 24 h after ICU admission is an essential predictor as to 30-day as well as 1-year mortality. When blood glucose fluctuates more than 88 mg/dl within 24 h, mortality increases significantly with the range of blood glucose fluctuations.

Electroacupuncture alleviates streptozotocin-induced diabetic neuropathic pain via suppressing phosphorylated CaMKIIα in rats

Diabetic neuropathic pain (DNP) is a frequent complication of diabetes. Calcium/calmodulin-dependent protein kinase II α (CaMKIIα), a multi-functional serine/threonine kinase subunit, is mainly located in the surface layer of the spinal cord dorsal horn (SCDH) and the primary sensory neurons in dorsal root ganglion (DRG). Numerous studies have indicated electroacupuncture (EA) takes effect in various kinds of pain. In this research, we explored whether CaMKIIα on rats' SCDH and DRG participated in DNP and further explored the mechanisms underlying the analgesic effects of EA. The DNP model in rats was successfully established by intraperitoneal injection of streptozotocin. Certain DNP rats were treated with intrathecal injections of KN93, a CaMKII antagonist, and some of the DNP rats received EA intervention. The general conditions, behaviors, the expressions of CaMKIIα and phosphorylated CaMKIIα (p-CaMKIIα) were evaluated. DNP rats' paw withdrawal threshold was reduced and the expressions of p-CaMKIIα in SCDH and DRG were upregulated compared with the Normal group, while the level of CaMKIIα showed no significance. KN93 attenuated DNP rats' hyperalgesia and reduced the expressions of p-CaMKIIα. We also found EA attenuated the hyperalgesia of DNP rats and reduced the expressions of p-CaMKIIα. The above findings suggest that p-CaMKIIα in SCDH and DRG is involved in DNP. The analgesic effect of EA in DNP might be related to the downregulation of p-CaMKIIα expression level. Our study further supports that EA can be an effective clinical treatment for DNP.

Furin knockdown inhibited EndMT and abnormal proliferation and migration of endothelial cells

BACKGROUND

In the pathogenesis of atherosclerotic cardiovascular disorders, vascular endothelium is crucial. A critical step in the development of atherosclerosis is endothelial dysfunction. Furin may play a factor in vascular remodeling, inflammatory cell infiltration, regulation of plaque stability, and atherosclerosis by affecting the adhesion and migration of endothelial cells. It is yet unknown, though, how furin contributes to endothelial dysfunction.

METHODS

We stimulated endothelial cells with oxidized modified lipoprotein (ox-LDL). Endothelial-to-mesenchymal transition (EndMT) was found using immunofluorescence (IF) and western blot (WB). Furin expression level and Hippo/YAP signal activation were found using reverse transcription-quantitative PCR (RT-qPCR) and WB, respectively. To achieve the goal of furin knockdown, we transfected siRNA using the RNA transmate reagent. Following furin knockdown, cell proliferation, and migration were assessed by the CCK-8, scratch assay, and transwell gold assay, respectively. WB and IF both picked up on EndMT. WB and RT-qPCR, respectively, were used to find furin's expression level. We chose the important micrornas that can regulate furin and we then confirmed them using RT-qPCR.

RESULTS

EndMT was created by ox-LDL, evidenced by the up-regulation of mesenchymal cell markers and the down-regulation of endothelial cell markers. Furin expression levels in both protein and mRNA were increased, and the Hippo/YAP signaling pathway was turned on. Furin knockdown dramatically reduced the aberrant migration and proliferation of endothelial cells by ox-LDL stimulation. Furin knockdown can also suppress ox-LDL-induced EndMT, up-regulate indicators of endothelial cells, and down-regulate markers of mesenchymal cells. After ox-LDL stimulation and siRNA transfection, furin's expression level was up-regulated and down-regulated.

CONCLUSION

Our study demonstrated that furin knockdown could affect ox-LDL-induced abnormal endothelial cell proliferation, migration, and EndMT. This implies that furin plays an important role in endothelial dysfunction.

Outcomes Associated with Sodium-Glucose Cotransporter-2 Inhibitor Use in Acute Heart Failure Hospitalizations Complicated by AKI

Key Points

In a multicenter retrospective cohort study of adults hospitalized with acute heart failure, exposure to sodium-glucose cotransporter-2 inhibitor during AKI was associated with lower risk of 30-day mortality. Exposure to sodium-glucose cotransporter-2 inhibitor during acute heart failure–associated AKI was associated with no difference in time to renal recovery. The findings were reproducible in inverse probability-weighted analysis.

Background

Although sodium-glucose cotransporter-2 inhibitor (SGLT2i) use during acute heart failure (AHF) hospitalizations is associated with symptomatic improvement, reduction in rehospitalizations, and mortality, these medications are often withheld during AKI because of concerns about worsening GFR. We aimed to investigate the safety of SGLT2i exposure during AKI among patients hospitalized with AHF. We hypothesized that SGLT2i exposure would not worsen mortality but may prolong return of creatinine to baseline.

Methods

This was a retrospective study of adults hospitalized across five Yale New Haven Health System hospitals between January 2020 and May 2022 with AHF complicated by Kidney Disease Improving Global Outcomes–defined AKI. Patients with stage 5 CKD and those with potential contraindications to SGLT2i were excluded. We tested the association of SGLT2i use with kidney function recovery at 14 days and death at 30 days using time-varying, multivariable Cox-regression analyses.

Results

Of 3305 individuals hospitalized with AHF and AKI, 356 received SGLT2i after AKI diagnosis either as initiation or continuation. The rate of renal recovery was not significantly different among those exposed and unexposed to SGLT2i after AKI (adjusted hazard ratio, 0.94; 95% confidence interval, 0.79 to 1.11; P = 0.46). SGLT2i exposure was associated with lower risk of 30-day mortality (adjusted hazard ratio, 0.45; 95% confidence interval, 0.23 to 0.87; P = 0.02). Sensitivity analyses using an inverse probability-weighted time-varying Cox regression analysis and using alternate definitions of AHF with different NT-proBNP cutoffs yielded similar results. Rates of renal recovery were similar between the exposed and unexposed cohorts regardless of the proximity of SGLT2i exposure to AKI diagnosis.

Conclusion

In adults experiencing AHF-associated AKI, exposure to SGLT2i was associated with decreased mortality and no delay in renal recovery. Prospective studies are needed to elucidate the effect of SGLT2i exposure during AKI, particularly during heart failure hospitalizations.

Unsuspected diabetic ketoacidosis after myocardial infarction in a patient treated with SGLT2 inhibitor increased length of stay in the hospital: how can it be prevented? A case report

Background

As the use of sodium-glucose co-transporter 2 inhibitors (SGLT2is) has expanded beyond glucose-lowering therapy in type 2 diabetes mellitus (T2DM), including chronic kidney disease and heart failure, there has also been an increase in reported cases of diabetic ketoacidosis (DKA) associated with SGLT2i.

Case summary

A 77-year-old woman with T2DM presented to the emergency department with ST-segment elevation myocardial infarction (MI) complicated by atrial fibrillation. Her medications included empagliflozin, an SGLT2i, initiated for T2DM. Diabetic ketoacidosis was suspected on the basis of a large anion gap, despite a plasma glucose level below 200 mg/dL (11.1 mmol/L) and the absence of symptoms, including nausea and vomiting. Laboratory tests confirmed metabolic acidosis and high ketones. However, the diagnosis of euglycaemic DKA (eu-DKA) was delayed due to lack of symptoms and moderate hyperglycaemia. The patient was successfully treated according to DKA management guidelines. She was discharged on insulin, and SGLT2i was discontinued.

Discussion

This is a case of asymptomatic eu-DKA after acute MI (AMI). We discuss the use of SGLT2is in AMI and arrhythmias from a review of the literature and the prophylaxis of eu-DKA. Regular monitoring of blood glucose and ketones should be performed in hospitalized T2DM patients treated with SGLT2i. The SGLT2i should be stopped as soon as possible in the event of critical illness or suspected DKA in the setting of an acute illness such as AMI. To help clinicians prevent this potentially fatal disease, we propose a flowchart for the prophylactic management of eu-DKA among inpatients.

A bibliometric analysis of myocardial ischemia/reperfusion injury from 2000 to 2023

Background

Myocardial ischemia/reperfusion injury (MIRI) refers to the more severe damage that occurs in the previously ischemic myocardium after a short-term interruption of myocardial blood supply followed by restoration of blood flow within a certain period of time. MIRI has become a major challenge affecting the therapeutic efficacy of cardiovascular surgery.

Methods

A scientific literature search on MIRI-related papers published from 2000 to 2023 in the Web of Science Core Collection database was conducted. VOSviewer was used for bibliometric analysis to understand the scientific development and research hotspots in this field.

Results

A total of 5,595 papers from 81 countries/regions, 3,840 research institutions, and 26,202 authors were included. China published the most papers, but the United States had the most significant influence. Harvard University was the leading research institution, and influential authors included Lefer David J., Hausenloy Derek J., Yellon Derek M., and others. All keywords can be divided into four different directions: risk factors, poor prognosis, mechanisms and cardioprotection.

Conclusion

Research on MIRI is flourishing. It is necessary to conduct an in-depth investigation of the interaction between different mechanisms and multi-target therapy will be the focus and hotspot of MIRI research in the future.

Pharmacological Cardioprotection against Ischemia Reperfusion Injury-The Search for a Clinical Effective Therapy

Pharmacological conditioning aims to protect the heart from myocardial ischemia-reperfusion injury (IRI). Despite extensive research in this area, today, a significant gap remains between experimental findings and clinical practice. This review provides an update on recent developments in pharmacological conditioning in the experimental setting and summarizes the clinical evidence of these cardioprotective strategies in the perioperative setting. We start describing the crucial cellular processes during ischemia and reperfusion that drive acute IRI through changes in critical compounds (∆G_ATP, Na⁺, Ca²⁺, pH, glycogen, succinate, glucose-6-phosphate, mitoHKII, acylcarnitines, BH₄, and NAD⁺). These compounds all precipitate common end-effector mechanisms of IRI, such as reactive oxygen species (ROS) generation, Ca²⁺ overload, and mitochondrial permeability transition pore opening (mPTP). We further discuss novel promising interventions targeting these processes, with emphasis on cardiomyocytes and the endothelium. The limited translatability from basic research to clinical practice is likely due to the lack of comorbidities, comedications, and peri-operative treatments in preclinical animal models, employing only monotherapy/monointervention, and the use of no-flow (always in preclinical models) versus low-flow ischemia (often in humans). Future research should focus on improved matching between preclinical models and clinical reality, and on aligning multitarget therapy with optimized dosing and timing towards the human condition.

SGLT2 inhibitor dapagliflozin alleviates intramyocardial hemorrhage and adverse ventricular remodeling via suppressing hepcidin in myocardial ischemia-reperfusion injury

Intramyocardial hemorrhage (IMH), a reperfusion therapy-associated complication, is the extravasation of red blood cells caused by severe microvascular injury. IMH is an independent predictor of adverse ventricular remodeling (AVR) after acute myocardial infarction (AMI). Hepcidin, a major regulator of iron uptake and systemic distribution, is a key factor affecting AVR. However, the role of cardiac hepcidin in the development of IMH has not been completely elucidated. This study aimed to explore if sodium-dependent glucose co-transporter 2 inhibitor (SGLT2i) exerts therapeutic effects on IMH and AVR by suppressing hepcidin and to elucidate the underlying mechanisms. SGLT2i alleviated IMH and AVR in the ischemia-reperfusion injury (IRI) mouse model. Additionally, SGLT2i downregulated the cardiac levels of hepcidin in IRI mice, suppressed M1-type macrophage polarization, and promoted M2-type macrophage polarization. The effects of hepcidin knockdown on macrophage polarization were similar to those of SGLT2i in RAW264.7 cells. SGLT2i treatment or hepcidin knockdown inhibited the expression of MMP9, an inducer of IMH and AVR, in RAW264.7 cells. Regulation of macrophage polarization and reduction of MMP9 expression by SGLT2i and hepcidin knockdown is achieved through activation of pSTAT3. In conclusion, this study demonstrated that SGLT2i alleviated IMH and AVR by regulating macrophage polarization. The potential mechanism through which SGLT2i exerted its therapeutic effect seems to involve the downregulation of MMP9 via the hepcidin-STAT3 pathway.

Canagliflozin Improves Myocardial Perfusion, Fibrosis, and Function in a Swine Model of Chronic Myocardial Ischemia

Background Sodium-glucose cotransporter-2 inhibitors are cardioprotective independent of glucose control, as demonstrated in animal models of acute myocardial ischemia and clinical trials. The functional and molecular mechanisms of these benefits in the setting of chronic myocardial ischemia are poorly defined. The purpose of this study is to determine the effects of canagliflozin therapy on myocardial perfusion, fibrosis, and function in a large animal model of chronic myocardial ischemia. Methods and Results Yorkshire swine underwent placement of an ameroid constrictor to the left circumflex artery to induce chronic myocardial ischemia. Two weeks later, pigs received either no drug (n=8) or 300 mg sodium-glucose cotransporter-2 inhibitor canagliflozin orally, daily (n=8). Treatment continued for 5 weeks, followed by hemodynamic measurements, harvest, and tissue analysis. Canagliflozin therapy was associated with increased stroke volume and stroke work and decreased left ventricular stiffness compared with controls. The canagliflozin group had improved perfusion to ischemic myocardium compared with controls, without differences in arteriolar or capillary density. Canagliflozin was associated with decreased interstitial and perivascular fibrosis in chronically ischemic tissue, with reduced Jak/STAT (Janus kinase/signal transducer and activator of transcription) signaling compared with controls. In ischemic myocardium of the canagliflozin group, there was increased expression and activation of adenosine monophosphate-activated protein kinase, decreased activation of endothelial nitric oxide synthase, and unchanged total endothelial nitric oxide synthase. Canagliflozin therapy reduced total protein oxidation and increased expression of mitochondrial antioxidant superoxide dismutase 2 compared with controls. Conclusions In the setting of chronic myocardial ischemia, canagliflozin therapy improves myocardial function and perfusion to ischemic territory, without changes in collateralization. Attenuation of fibrosis via reduced Jak/STAT signaling, activation of adenosine monophosphate-activated protein kinase, and antioxidant signaling may contribute to these effects.

Outcomes in diabetic patients treated with SGLT2-Inhibitors with acute myocardial infarction undergoing PCI: The SGLT2-I AMI PROTECT Registry

AIMS

To investigate in-hospital and long-term prognosis in T2DM patients presenting with acute myocardial infarction (AMI) treated with SGLT2-I versus other oral anti-diabetic agents (non-SGLT2-I users).

METHODS

In this multicenter international registry all consecutive diabetic AMI patients undergoing percutaneous coronary intervention between 2018 and 2021 were enrolled and, based on the admission anti-diabetic therapy, divided into SGLT-I users versus non-SGLT2-I users. The primary endpoint was defined as a composite of cardiovascular death, recurrent AMI, and hospitalization for HF (MACE). Secondary outcomes included i) in-hospital cardiovascular death, recurrent AMI, occurrence of arrhythmias, and contrast-induced acute kidney injury (CI-AKI); ii) long-term cardiovascular mortality, recurrent AMI, heart failure (HF) hospitalization.

RESULTS

The study population consisted of 646 AMI patients (with or without ST-segment elevation): 111 SGLT2-I users and 535 non-SGLT-I users. The use of SGLT2-I was associated with a significantly lower in-hospital cardiovascular death, arrhythmic burden, and occurrence of CI-AKI (all p < 0.05). During a median follow-up of 24 ± 13 months, the primary composite endpoint, as well as cardiovascular mortality and HF hospitalization were lower for SGLT2-I users compared to non-SGLT2-I patients (p < 0.04 for all). After adjusting for confounding factors, the use of SGLT2-I was identified as independent predictor of reduced MACE occurrence (HR=0.57; 95%CI:0.33-0.99; p = 0.039) and HF hospitalization (HR=0.46; 95%CI:0.21-0.98; p = 0.041).

CONCLUSIONS

In T2DM AMI patients, the use of SGLT2-I was associated with a lower risk of adverse cardiovascular outcomes during index hospitalization and long-term follow-up. Our findings provide new insights into the cardioprotective effects of SGLT2-I in the setting of AMI.

REGISTRATION

Data are part of the observational international registry: SGLT2-I AMI PROTECT.

CLINICALTRIALS

gov Identifier: NCT05261867.

Interaction of Cardiovascular Nonmodifiable Risk Factors, Comorbidities and Comedications With Ischemia/Reperfusion Injury and Cardioprotection by Pharmacological Treatments and Ischemic Conditioning

Preconditioning, postconditioning, and remote conditioning of the myocardium enhance the ability of the heart to withstand a prolonged ischemia/reperfusion insult and the potential to provide novel therapeutic paradigms for cardioprotection. While many signaling pathways leading to endogenous cardioprotection have been elucidated in experimental studies over the past 30 years, no cardioprotective drug is on the market yet for that indication. One likely major reason for this failure to translate cardioprotection into patient benefit is the lack of rigorous and systematic preclinical evaluation of promising cardioprotective therapies prior to their clinical evaluation, since ischemic heart disease in humans is a complex disorder caused by or associated with cardiovascular risk factors and comorbidities. These risk factors and comorbidities induce fundamental alterations in cellular signaling cascades that affect the development of ischemia/reperfusion injury and responses to cardioprotective interventions. Moreover, some of the medications used to treat these comorbidities may impact on cardioprotection by again modifying cellular signaling pathways. The aim of this article is to review the recent evidence that cardiovascular risk factors as well as comorbidities and their medications may modify the response to cardioprotective interventions. We emphasize the critical need for taking into account the presence of cardiovascular risk factors as well as comorbidities and their concomitant medications when designing preclinical studies for the identification and validation of cardioprotective drug targets and clinical studies. This will hopefully maximize the success rate of developing rational approaches to effective cardioprotective therapies for the majority of patients with multiple comorbidities. SIGNIFICANCE STATEMENT: Ischemic heart disease is a major cause of mortality; however, there are still no cardioprotective drugs on the market. Most studies on cardioprotection have been undertaken in animal models of ischemia/reperfusion in the absence of comorbidities; however, ischemic heart disease develops with other systemic disorders (e.g., hypertension, hyperlipidemia, diabetes, atherosclerosis). Here we focus on the preclinical and clinical evidence showing how these comorbidities and their routine medications affect ischemia/reperfusion injury and interfere with cardioprotective strategies.

Dapagliflozin alleviates myocardial ischemia/reperfusion injury by reducing ferroptosis via MAPK signaling inhibition

Reperfusion is essential for ischemic myocardium but paradoxically leads to myocardial damage that worsens cardiac functions. Ferroptosis often occurs in cardiomyocytes during ischemia/reperfusion (I/R). The SGLT2 inhibitor dapagliflozin (DAPA) exerts cardioprotective effects independent of hypoglycemia. Here, we investigated the effect and potential mechanism of DAPA against myocardial ischemia/reperfusion injury (MIRI)-related ferroptosis using the MIRI rat model and hypoxia/reoxygenation (H/R)-induced H9C2 cardiomyocytes. Our results show that DAPA significantly ameliorated myocardial injury, reperfusion arrhythmia, and cardiac function, as evidenced by alleviated ST-segment elevation, ameliorated cardiac injury biomarkers including cTnT and BNP and pathological features, prevented H/R-triggered cell viability loss in vitro. In vitro and in vivo experiments showed that DAPA inhibited ferroptosis by upregulating the SLC7A11/GPX4 axis and FTH and inhibiting ACSL4. DAPA notably mitigated oxidative stress, lipid peroxidation, ferrous iron overload, and reduced ferroptosis. Subsequently, network pharmacology and bioinformatics analysis suggested that the MAPK signaling pathway was a potential target of DAPA and a common mechanism of MIRI and ferroptosis. DAPA treatment significantly reduced MAPK phosphorylation in vitro and in vivo, suggesting that DAPA might protect against MIRI by reducing ferroptosis through the MAPK signaling pathway.

Cost-effectiveness of empagliflozin for the treatment of heart failure with reduced ejection fraction in China

AIM

To determine the pharmacoeconomics of empagliflozin for the treatment of heart failure (HF) with reduced ejection fraction in China and to provide evidence-based reference for clinical rational drug selection and medical decision-making.

RESEARCH DESIGN AND METHODS

We used the Markov model to evaluate the cost-effectiveness of empagliflozin for the treatment of HF with reduced ejection fraction (HFrEF). We evaluated the cost-effectiveness of the standard treatment in addition to empagliflozin (empagliflozin group) vs. the cost-effectiveness of the standard treatment alone (standard treatment group).

RESULTS

We found that each additional quality-adjusted life year (QALY) in the empagliflozin group costed $3,842.20 more, which was less than China's gross domestic product (GDP) per capita in 2021 ($11,981). The steady-state mortality in the two groups was the key factor affecting the incremental cost-effectiveness ratio (ICER). Probabilistic sensitivity analysis revealed that when the willingness-to-pay (WTP) threshold was one time the GDP per capita in 2021 ($11,981) and three times the GDP per capita in 2021 ($35,943), the probability of the empagliflozin group being cost-effective was 85.8 and 91.6%, respectively.

CONCLUSION

Compared with the standard treatment alone, the addition of empagliflozin to the standard treatment was more cost-effective for the treatment of HFrEF in China.

SGLT2 Inhibitors: New Hope for the Treatment of Acute Myocardial Infarction?

Among all of the new antidiabetic drugs, an increasing number of studies have evaluated the relationship between the sodium-glucose cotransporter 2 inhibitors (SGLT2i) and acute myocardial infarction (AMI). Since SGLT2i like empagliflozin, canagliflozin, and recently, dapagliflozin have shown impressive positive effects in patients with chronic heart failure with reduced ejection fraction (HFrEF), it has increased research interest to explore the cardiac molecular mechanisms underlying the clinical benefits and attracted more attention to the effects of SGLT2i on a series of cardiovascular events. Experimental and clinical data on SGLT2i treatment after AMI is limited. This is a review of the clinical and preclinical effects of SGLT2i, focusing on available data on the effects of SGLT2i in AMI patients with a brief overview of ongoing trials.

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

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

Left Ventricular Remodeling after Myocardial Infarction: From Physiopathology to Treatment

Myocardial infarction (MI) is the leading cause of death and morbidity worldwide, with an incidence relatively high in developed countries and rapidly growing in developing countries. The most common cause of MI is the rupture of an atherosclerotic plaque with subsequent thrombotic occlusion in the coronary circulation. This causes cardiomyocyte death and myocardial necrosis, with subsequent inflammation and fibrosis. Current therapies aim to restore coronary flow by thrombus dissolution with pharmaceutical treatment and/or intravascular stent implantation and to counteract neurohormonal activation. Despite these therapies, the injury caused by myocardial ischemia leads to left ventricular remodeling; this process involves changes in cardiac geometry, dimension and function and eventually progression to heart failure (HF). This review describes the pathophysiological mechanism that leads to cardiac remodeling and the therapeutic strategies with a role in slowing the progression of remodeling and improving cardiac structure and function.

The Chinese medicine Fufang Zhenzhu Tiaozhi capsule protects against atherosclerosis by suppressing EndMT via modulating Akt1/β-catenin signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Fufang Zhenzhu Tiaozhi (FTZ) is a traditional Chinese herbal prescription that has been used to treat dyslipidemia, nonalcoholic fatty liver disease, atherosclerosis, diabetes and its complications in the clinic for almost ten years. Endothelial-mesenchymal transition (EndMT) is the key driver of atherosclerosis. However, the effects of FTZ on endothelial dysfunction and EndMT remain unknown.

AIM OF THE STUDY

To evaluate the therapeutic effects of FTZ against EndMT and the underlying mechanisms.

MATERIALS AND METHODS

An in vivo model of atherosclerosis was established by feeding ApoE^-/- mice with a high-fat diet (HFD). The body weight, lipid levels, plaque area, lipid deposition and EndMT were evaluated using standard assays 12 weeks after intragastric administration of FTZ and simvastatin. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL) to simulate EndMT in vitro. The degree of EndMT was assessed after treating the cells with FTZ or transfection with si-Akt1. The expression levels of genes involved in EndMT were quantified by real-time PCR or western blotting.

RESULTS

FTZ ameliorated dyslipidemia and endothelial dysfunction in the atherosclerotic mice. In addition, FTZ reduced body weight and the total cholesterol, triglycerides and low-density lipoprotein levels, and increased that of high-density lipoproteins. FTZ also upregulated the expression of endothelial markers (CD31 and VE-cadherin) and decreased that of mesenchymal markers (ɑ-SMA and FSP1), indicating that it inhibits EndMT. Knocking down Akt1 exacerbated EndMT and reversed the therapeutic effect of FTZ.

CONCLUSION

FTZ delayed atherosclerosis by inhibiting EndMT via the Akt1/β-catenin pathway.

Sodium-Glucose Cotransporter-2 Inhibitors-from the Treatment of Diabetes to Therapy of Chronic Heart Failure

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are currently the second-line pharmacotherapy in type 2 diabetes, particularly through their effectiveness in reducing glycemia, but also due to their cardioprotective and nephroprotective effects. In light of surprisingly satisfactory results from large, randomized trials on gliflozins, SGLT2 received the highest recommendation (Class IA) with the highest level of evidence (A) in the treatment algorithm for HF with reduced LVEF in recent ESC HF guidelines. This great breakthrough in the treatment of HF is due to different mechanisms of action of gliflozins that are reported to be able to change the natural course of HF by reducing the risk of both hospitalization and death. They are recommended regardless of the patient’s diabetes status. This review summarizes the up-to-date literature on their beneficial and pleiotropic impact on the cardiovascular system.

Role of Oxidative Stress in Cardiac Dysfunction and Subcellular Defects Due to Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury is well-known to be associated with impaired cardiac function, massive arrhythmias, marked alterations in cardiac metabolism and irreversible ultrastructural changes in the heart. Two major mechanisms namely oxidative stress and intracellular Ca²⁺-overload are considered to explain I/R-induced injury to the heart. However, it is becoming apparent that oxidative stress is the most critical pathogenic factor because it produces myocardial abnormalities directly or indirectly for the occurrence of cardiac damage. Furthermore, I/R injury has been shown to generate oxidative stress by promoting the formation of different reactive oxygen species due to defects in mitochondrial function and depressions in both endogenous antioxidant levels as well as regulatory antioxidative defense systems. It has also been demonstrated to adversely affect a wide variety of metabolic pathways and targets in cardiomyocytes, various resident structures in myocardial interstitium, as well as circulating neutrophils and leukocytes. These I/R-induced alterations in addition to myocardial inflammation may cause cell death, fibrosis, inflammation, Ca²⁺-handling abnormalities, activation of proteases and phospholipases, as well as subcellular remodeling and depletion of energy stores in the heart. Analysis of results from isolated hearts perfused with or without some antioxidant treatments before subjecting to I/R injury has indicated that cardiac dysfunction is associated with the development of oxidative stress, intracellular Ca²⁺-overload and protease activation. In addition, changes in the sarcolemma and sarcoplasmic reticulum Ca²⁺-handling, mitochondrial oxidative phosphorylation as well as myofibrillar Ca²⁺-ATPase activities in I/R hearts were attenuated by pretreatment with antioxidants. The I/R-induced alterations in cardiac function were simulated upon perfusing the hearts with oxyradical generating system or oxidant. These observations support the view that oxidative stress may be intimately involved in inducing intracellular Ca²⁺-overload, protease activation, subcellular remodeling, and cardiac dysfunction as a consequence of I/R injury to the heart.

Cardioprotection by selective SGLT-2 inhibitors in a non-diabetic mouse model of myocardial ischemia/reperfusion injury: a class or a drug effect?

Major clinical trials with sodium glucose co-transporter-2 inhibitors (SGLT-2i) exhibit protective effects against heart failure events, whereas inconsistencies regarding the cardiovascular death outcomes are observed. Therefore, we aimed to compare the selective SGLT-2i empagliflozin (EMPA), dapagliflozin (DAPA) and ertugliflozin (ERTU) in terms of infarct size (IS) reduction and to reveal the cardioprotective mechanism in healthy non-diabetic mice. C57BL/6 mice randomly received vehicle, EMPA (10 mg/kg/day) and DAPA or ERTU orally at the stoichiometrically equivalent dose (SED) for 7 days. 24 h-glucose urinary excretion was determined to verify SGLT-2 inhibition. IS of the region at risk was measured after 30 min ischemia (I), and 120 min reperfusion (R). In a second series, the ischemic myocardium was collected (10th min of R) for shotgun proteomics and evaluation of the cardioprotective signaling. In a third series, we evaluated the oxidative phosphorylation capacity (OXPHOS) and the mitochondrial fatty acid oxidation capacity by measuring the respiratory rates. Finally, Stattic, the STAT-3 inhibitor and wortmannin were administered in both EMPA and DAPA groups to establish causal relationships in the mechanism of protection. EMPA, DAPA and ERTU at the SED led to similar SGLT-2 inhibition as inferred by the significant increase in glucose excretion. EMPA and DAPA but not ERTU reduced IS. EMPA preserved mitochondrial functionality in complex I&II linked oxidative phosphorylation. EMPA and DAPA treatment led to NF-kB, RISK, STAT-3 activation and the downstream apoptosis reduction coinciding with IS reduction. Stattic and wortmannin attenuated the cardioprotection afforded by EMPA and DAPA. Among several upstream mediators, fibroblast growth factor-2 (FGF-2) and caveolin-3 were increased by EMPA and DAPA treatment. ERTU reduced IS only when given at the double dose of the SED (20 mg/kg/day). Short-term EMPA and DAPA, but not ERTU administration at the SED reduce IS in healthy non-diabetic mice. Cardioprotection is not correlated to SGLT-2 inhibition, is STAT-3 and PI3K dependent and associated with increased FGF-2 and Cav-3 expression.

Infarct size, inflammatory burden, and admission hyperglycemia in diabetic patients with acute myocardial infarction treated with SGLT2-inhibitors: a multicenter international registry

BACKGROUND

The inflammatory response occurring in acute myocardial infarction (AMI) has been proposed as a potential pharmacological target. Sodium-glucose co-transporter 2 inhibitors (SGLT2-I) currently receive intense clinical interest in patients with and without diabetes mellitus (DM) for their pleiotropic beneficial effects. We tested the hypothesis that SGLT2-I have anti-inflammatory effects along with glucose-lowering properties. Therefore, we investigated the link between stress hyperglycemia, inflammatory burden, and infarct size in a cohort of type 2 diabetic patients presenting with AMI treated with SGLT2-I versus other oral anti-diabetic (OAD) agents.

METHODS

In this multicenter international observational registry, consecutive diabetic AMI patients undergoing percutaneous coronary intervention (PCI) between 2018 and 2021 were enrolled. Based on the presence of anti-diabetic therapy at the admission, patients were divided into those receiving SGLT2-I (SGLT-I users) versus other OAD agents (non-SGLT2-I users). The following inflammatory markers were evaluated at different time points: white-blood-cell count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), neutrophil-to-platelet ratio (NPR), and C-reactive protein. Infarct size was assessed by echocardiography and by peak troponin levels.

RESULTS

The study population consisted of 583 AMI patients (with or without ST-segment elevation): 98 SGLT2-I users and 485 non-SGLT-I users. Hyperglycemia at admission was less prevalent in the SGLT2-I group. Smaller infarct size was observed in patients treated with SGLT2-I compared to non-SGLT2-I group. On admission and at 24 h, inflammatory indices were significantly higher in non-SGLT2-I users compared to SGLT2-I patients, with a significant increase in neutrophil levels at 24 h. At multivariable analysis, the use of SGLT2-I was a significant predictor of reduced inflammatory response (OR 0.457, 95% CI 0.275-0.758, p = 0.002), independently of age, admission creatinine values, and admission glycemia. Conversely, peak troponin values and NSTEMI occurrence were independent predictors of a higher inflammatory status.

CONCLUSIONS

Type 2 diabetic AMI patients receiving SGLT2-I exhibited significantly reduced inflammatory response and smaller infarct size compared to those receiving other OAD agents, independently of glucose-metabolic control. Our findings are hypothesis generating and provide new insights on the cardioprotective effects of SGLT2-I in the setting of coronary artery disease.

TRIAL REGISTRATION

Data are part of the ongoing observational registry: SGLT2-I AMI PROTECT.

CLINICALTRIALS

gov Identifier: NCT05261867.

Effects of sodium-glucose cotransporter-2 inhibitors on cardiac structural and electrical remodeling: from myocardial cytology to cardiodiabetology

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have changed the clinical landscape of diabetes mellitus (DM) therapy through their favourable effects on cardiovascular outcomes. Notably, the use of SGLT2i has been linked to cardiovascular benefits regardless of DM status, while their pleiotropic actions remain to be fully elucidated. What we do know is that SGLT2i exert beneficial effects even at the level of the myocardial cell, and that these are linked to an improvement in the energy substrate, resulting in less inflammation and fibrosis. SGLT2i ameliorate myocardial extracellular matrix remodeling, cardiomyocyte stiffness and concentric hypertrophy, achieving beneficial remodeling of the left ventricle with significant implications for the pathogenesis and outcome of heart failure. Most studies show a significant improvement in markers of diastolic dysfunction along with a reduction in left ventricular hypertrophy. In addition to these effects there is electrophysiological remodeling, which explains initial data suggesting that SGLT2i have an antiarrhythmic action against both atrial and ventricular arrhythmias. However, future studies need to clarify not only the exact mechanisms of this beneficial functional, structural, and electrophysiological cardiac remodeling, but also its magnitude, and to determine whether this is a class or a drug effect.

Cost-Effectiveness of Adding SGLT2 Inhibitors to Standard Treatment for Heart Failure With Reduced Ejection Fraction Patients in China

Objective: To evaluate the economics and effectiveness of adding dapagliflozin or empagliflozin to the standard treatment for heart failure (HF) for patients with reduced ejection fraction (HFrEF) in China.

Methods: A Markov model was developed to project the clinical and economic outcomes of adding dapagliflozin or empagliflozin to the standard treatment for 66-year-old patients with HFrEF. A cost-utility analysis was performed based mostly on data from the empagliflozin outcome trial in patients with chronic heart failure and a reduced ejection fraction (EMPEROR-Reduced) study and the dapagliflozin and prevention of adverse outcomes in heart failure (DAPA-HF) trial. The primary outcomes were measured via total and incremental costs and quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio (ICER).

Results: In China, compared to the standard treatment, although adding dapagliflozin to the standard treatment in the treatment of HFrEF was more expensive ($4,870.68 vs. $3,596.25), it was more cost-effective (3.87 QALYs vs. 3.64 QALYs), resulting in an ICER of $5,541.00 per QALY. Similarly, adding empagliflozin was more expensive ($5,021.93 vs. $4,118.86) but more cost-effective (3.66 QALYs vs. 3.53 QALYs), resulting in an ICER of $6,946.69 per QALY. A sensitivity analysis demonstrated the robustness of the model in identifying cardiovascular death as a significant driver of cost-effectiveness. A probabilistic sensitivity analysis indicated that when the willingness-to-pay was $11,008.07 per QALY, the probability of the addition of dapagliflozin or empagliflozin being cost-effective was 70.5 and 55.2%, respectively. A scenario analysis showed that the cost of hospitalization, diabetes status, and time horizon had a greater impact on ICER.

Conclusion: Compared with standard treatments with or without empagliflozin, adding dapagliflozin to the standard treatment in the treatment of HFrEF in China was extremely cost-effective.

SGLT2 Inhibition for Cardiovascular Diseases, Chronic Kidney Disease, and NAFLD

Sodium glucose cotransporter 2 (SGLT-2) inhibitors are the latest class of antidiabetic medications. They prevent glucose reabsorption in the proximal convoluted tubule to decrease blood sugar. Several animal studies revealed that SGLT-2 is profoundly involved in the inflammatory response, fibrogenesis, and regulation of numerous intracellular signaling pathways. Likewise, SGLT-2 inhibitors markedly attenuated inflammation and fibrogenesis and improved the function of damaged organ in animal studies, observational studies, and clinical trials. SGLT-2 inhibitors can decrease blood pressure and ameliorate hypertriglyceridemia and obesity. Likewise, they improve the outcome of cardiovascular diseases such as heart failure, arrhythmias, and ischemic heart disease. SGLT-2 inhibitors are associated with lower cardiovascular and all-cause mortality as well. Meanwhile, they protect against nonalcoholic fatty liver disease (NAFLD), chronic kidney disease, acute kidney injury, and improve micro- and macroalbuminuria. SGLT-2 inhibitors can reprogram numerous signaling pathways to improve NAFLD, cardiovascular diseases, and renal diseases. For instance, they enhance lipolysis, ketogenesis, mitochondrial biogenesis, and autophagy while they attenuate the renin-angiotensin-aldosterone system, lipogenesis, endoplasmic reticulum stress, oxidative stress, apoptosis, and fibrogenesis. This review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases and dissects the underlying molecular mechanisms in detail. This narrative review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases using the results of latest observational studies, clinical trials, and meta-analyses. Thereafter, it dissects the underlying molecular mechanisms involved in the clinical effects of SGLT-2 inhibitors on these diseases.

Regulation of STAT3 and its role in cardioprotection by conditioning: focus on non-genomic roles targeting mitochondrial function

Ischemia–reperfusion injury (IRI) is one of the biggest challenges for cardiovascular researchers given the huge death toll caused by myocardial ischemic disease. Cardioprotective conditioning strategies, namely pre- and post-conditioning maneuvers, represent the most important strategies for stimulating pro-survival pathways essential to preserve cardiac health. Conditioning maneuvers have proved to be fundamental for the knowledge of the molecular basis of both IRI and cardioprotection. Among this evidence, the importance of signal transducer and activator of transcription 3 (STAT3) emerged. STAT3 is not only a transcription factor but also exhibits non-genomic pro-survival functions preserving mitochondrial function from IRI. Indeed, STAT3 is emerging as an influencer of mitochondrial function to explain the cardioprotection phenomena. Studying cardioprotection, STAT3 proved to be crucial as an element of the survivor activating factor enhancement (SAFE) pathway, which converges on mitochondria and influences their function by cross-talking with other cardioprotective pathways. Clearly there are still some functional properties of STAT3 to be discovered. Therefore, in this review, we highlight the evidence that places STAT3 as a promoter of the metabolic network. In particular, we focus on the possible interactions of STAT3 with processes aimed at maintaining mitochondrial functions, including the regulation of the electron transport chain, the production of reactive oxygen species, the homeostasis of Ca²⁺ and the inhibition of opening of mitochondrial permeability transition pore. Then we consider the role of STAT3 and the parallels between STA3/STAT5 in cardioprotection by conditioning, giving emphasis to the human heart and confounders.

Association of Circulating Ketone Bodies With Functional Outcomes After ST-Segment Elevation Myocardial Infarction

BACKGROUND

Circulating ketone bodies (KBs) are increased in patients with heart failure (HF), corresponding with increased cardiac KB metabolism and HF severity. However, the role of circulating KBs in ischemia/reperfusion remains unknown.

OBJECTIVES

This study sought to investigate longitudinal changes of KBs and their associations with functional outcomes in patients presenting with ST-segment elevation myocardial infarction (STEMI).

METHODS

KBs were measured in 369 participants from a randomized trial on early metformin therapy after STEMI. Nonfasting plasma concentrations of KBs (β-hydroxybutyrate, acetoacetate, and acetone) were measured by nuclear magnetic resonance spectroscopy at presentation, at 24 hours, and after 4 months. Myocardial infarct size and left ventricular ejection fraction (LVEF) were determined by cardiac magnetic resonance imaging at 4 months. Associations of circulating KBs with infarct size and LVEF were determined using multivariable linear regression analyses.

RESULTS

Circulating KBs were high at presentation with STEMI (median total KBs: 520 μmol/L; interquartile range [IQR]: 315-997 μmol/L). At 24 hours after reperfusion, KBs were still high compared with levels at 4-month follow-up (206 μmol/L [IQR: 174-246] vs 166 μmol/L [IQR: 143-201], respectively; P < 0.001). Increased KB concentrations at 24 hours were independently associated with larger myocardial infarct size (total KBs, per 100 μmol/L: β = 1.56; 95% confidence interval: 0.29-2.83; P = 0.016) and lower LVEF (β = -1.78; 95% CI: (-3.17 to -0.39; P = 0.012).

CONCLUSIONS

Circulating KBs are increased in patients presenting with STEMI. Higher KBs at 24 hours are associated with functional outcomes after STEMI, which suggests a potential role for ketone metabolism in response to myocardial ischemia. (Metabolic Modulation With Metformin to Reduce Heart Failure After Acute Myocardial Infarction: Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction (GIPS-III): a Randomized Controlled Trial; NCT01217307).

Cardioprotecive Properties of Known Agents in Rat Ischemia-Reperfusion Model Under Clinically Relevant Conditions: Only the NAD Precursor Nicotinamide Riboside Reduces Infarct Size in Presence of Fentanyl, Midazolam and Cangrelor, but Not Propofol

Background: Cardioprotective strategies against ischemia-reperfusion injury (IRI) that remain effective in the clinical arena need to be developed. Therefore, maintained efficacy of cardioprotective strategies in the presence of drugs routinely used clinically (e.g., opiates, benzodiazepines, P2Y₁₂ antagonist, propofol) need to be identified in preclinical models. Methods: Here, we examined the efficacy of promising cardioprotective compounds [fingolimod (Fingo), empagliflozin (Empa), melatonin (Mela) and nicotinamide riboside (NR)] administered i.v. as bolus before start ischemia. Infarct size as percentage of the area of risk (IS%) was determined following 25 min of left ascending coronary (LAD) ischemia and 2 h of reperfusion in a fentanyl-midazolam anesthetized IRI rat model. Plasma lactate dehydrogenase (LDH) activity at 30 min reperfusion was determined as secondary outcome parameter. Following pilot dose-response experiments of each compound (3 dosages, n = 4-6 animals per dosage), potential cardioprotective drugs at the optimal observed dosage were subsequently tested alone or in combination (n = 6-8 animals per group). The effective treatment was subsequently tested in the presence of a P2Y₁₂ antagonist (cangrelor; n = 6/7) or propofol aesthesia (n = 6 both groups). Results: Pilot studies suggested potential cardioprotective effects for 50 mg/kg NR (p = 0.005) and 500 μg/kg melatonin (p = 0.12), but not for Empa or Fingo. Protection was subsequently tested in a new series of experiments for solvents, NR, Mela and NR+Mela. Results demonstrated that only singular NR was able to reduce IS% (30 ± 14 vs. 60 ± 16%, P = 0.009 vs. control). Mela (63 ± 18%) and NR+Mela (47 ± 15%) were unable to significantly decrease IS%. NR still reduced IS in the presence of cangrelor (51 ± 18 vs. 71 ± 4%, P = 0.016 vs. control), but lost protection in the presence of propofol anesthesia (62 ± 16 vs. 60 ± 14%, P = 0.839 vs. control). LDH activity measurements supported all IS% results. Conclusion: This observational study suggests that NR is a promising cardioprotective agent to target cardiac ischemia-reperfusion injury in clinical conditions employing opioid agonists, benzodiazepines and platelet P2Y₁₂ inhibitors, but not propofol.

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

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

CaMKII in Regulation of Cell Death During Myocardial Reperfusion Injury

Cardiovascular disease is the leading cause of death worldwide. In spite of the mature managements of myocardial infarction (MI), post-MI reperfusion (I/R) injury results in high morbidity and mortality. Cardiomyocyte Ca²⁺ overload is a major factor of I/R injury, initiating a cascade of events contributing to cardiomyocyte death and myocardial dysfunction. Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) plays a critical role in cardiomyocyte death response to I/R injury, whose activation is a key feature of myocardial I/R in causing intracellular mitochondrial swelling, endoplasmic reticulum (ER) Ca²⁺ leakage, abnormal myofilament contraction, and other adverse reactions. CaMKII is a multifunctional serine/threonine protein kinase, and CaMKIIδ, the dominant subtype in heart, has been widely studied in the activation, location, and related pathways of cardiomyocytes death, which has been considered as a potential targets for pharmacological inhibition. In this review, we summarize a brief overview of CaMKII with various posttranslational modifications and its properties in myocardial I/R injury. We focus on the molecular mechanism of CaMKII involved in regulation of cell death induced by myocardial I/R including necroptosis and pyroptosis of cardiomyocyte. Finally, we highlight that targeting CaMKII modifications and cell death involved pathways may provide new insights to understand the conversion of cardiomyocyte fate in the setting of myocardial I/R injury.

SCAI expert consensus update on best practices in the cardiac catheterization laboratory: This statement was endorsed by the American College of Cardiology (ACC), the American Heart Association (AHA), and the Heart Rhythm Society (HRS) in April 2021

The current document commissioned by the Society for Cardiovascular Angiography and Interventions (SCAI) and endorsed by the American College of Cardiology, the American Heart Association, and Heart Rhythm Society represents a comprehensive update to the 2012 and 2016 consensus documents on patient-centered best practices in the cardiac catheterization laboratory. Comprising updates to staffing and credentialing, as well as evidence-based updates to the pre-, intra-, and post-procedural logistics, clinical standards and patient flow, the document also includes an expanded section on CCL governance, administration, and approach to quality metrics. This update also acknowledges the collaboration with various specialties, including discussion of the heart team approach to management, and working with electrophysiology colleagues in particular. It is hoped that this document will be utilized by hospitals, health systems, as well as regulatory bodies involved in assuring and maintaining quality, safety, efficiency, and cost-effectiveness of patient throughput in this high volume area.

Exosomes Protect Against Acute Myocardial Infarction in Rats by Regulating the Renin-Angiotensin System

The renin-angiotensin system (RAS) has been suggested to play an important role in cardiac remodeling after acute myocardial infarction (AMI). We have confirmed that bone marrow mesenchymal stem cell-derived exosomes (BMSC-EX) had similar types of repair like effects upon tissues as BMSC, but the mechanisms remain unknown. BMSC were cultured to the third generation and were induced to release exosomes. Rats were injected with exosomes (100 μg/mL) or stem cells (1 × 10⁶/mL) through the tail vein immediately after AMI was built, compared to those treated with physiological saline. Thereafter, all groups were analyzed for cardiac function, infarction sizes, and the levels of expression of BNP, ACE, ACE2, AngII, Ang1-7, and other factors in the plasma. After H₂O₂ makes contact with H9C2 cardiomyocytes, cell proliferation activity and apoptotic rates were measured by using CCK8 kits, to facilitate investigation of the effect of exosomes on H9C2 cells. In vivo, the index of cardiac remodeling and cardiac function was improved in both groups of exosomes and stem cells after AMI. Furthermore, exosomes may have helped to regulate the balance of the RAS system, upregulate ACE2-Ang1-7-Mas, and downregulate the ACE-AngII-ATIR pathway. Therefore, its effects were such as to accelerate the conversion of Ang II to Ang 1-7, thereby improving cardiac remodeling and forming sustained myocardial protection. In vitro, exosomal intervention was found to have increased the levels of activity of H9C2 cardiomyocytes under H₂O₂ injury and improved adverse effects of AngII upon H9C2 cells. All procedures for this study were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) at Guangdong Medical University. BMSC-EX improved cardiac remodeling and cardiac function, and had effects upon RAS system-related factors in plasma. Similarly, BMSC-EX also helped to protect H9C2 cells under attack from H₂O₂ or AngII, and may thus play beneficial roles by facilitating regulation of the balance of the RAS system.

Sodium-glucose cotransporter 2 inhibitors reduce myocardial infarct size in preclinical animal models of myocardial ischaemia-reperfusion injury: a meta-analysis

AIMS/HYPOTHESIS

Large cardiovascular outcome trials demonstrated that the cardioprotective effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors might reach beyond glucose-lowering action. In this meta-analysis, we sought to evaluate the potential infarct size-modulating effect of SGLT2 inhibitors in preclinical studies.

METHODS

In this preregistered meta-analysis (PROSPERO: CRD42020189124), we included placebo-controlled, interventional studies of small and large animal models of myocardial ischaemia-reperfusion injury, testing the effect of SGLT2 inhibitor treatment on myocardial infarct size (percentage of area at risk or total area). Standardised mean differences (SMDs) were calculated and pooled using random-effects method. We evaluated heterogeneity by computing Τ² and I² values. Meta-regression was performed to explore prespecified subgroup differences according to experimental protocols and their contribution to heterogeneity was assessed (pseudo-R² values).

RESULTS

We identified ten eligible publications, reporting 16 independent controlled comparisons on a total of 224 animals. Treatment with SGLT2 inhibitor significantly reduced myocardial infarct size compared with placebo (SMD = -1.30 [95% CI -1.79, -0.81], p < 0.00001), referring to a 33% [95% CI 20%, 47%] difference. Heterogeneity was moderate (Τ² = 0.58, I² = 60%). SGLT2 inhibitors were only effective when administered to the intact organ system, but not to isolated hearts (p interaction <0.001, adjusted pseudo-R² = 47%). While acute administration significantly reduced infarct size, chronic treatment was superior (p interaction <0.001, adjusted pseudo-R² = 85%). The medications significantly reduced infarct size in both diabetic and non-diabetic animals, favouring the former (p interaction = 0.030, adjusted pseudo-R² = 12%). Treatment was equally effective in rats and mice, as well as in a porcine model. Individual study quality scores were not related to effect estimates (p = 0.33). The overall effect estimate remained large even after adjusting for severe forms of publication bias.

CONCLUSIONS/INTERPRETATION

The glucose-lowering SGLT2 inhibitors reduce myocardial infarct size in animal models independent of diabetes. Future in vivo studies should focus on clinical translation by exploring whether SGLT2 inhibitors limit infarct size in animals with relevant comorbidities, on top of loading doses of antiplatelet agents. Mechanistic studies should elucidate the potential relationship between the infarct size-lowering effect of SGLT2 inhibitors and the intact organ system.