Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

Tirzepatide prevents neurodegeneration through multiple molecular pathways.

BACKGROUND: Several evidence demonstrated that glucagon-like peptide 1 receptor agonists (GLP1-RAs) reduce the risk of dementia in type 2 diabetes patients by improving memory, learning, and overcoming cognitive impairment. In this study, we elucidated the molecular processes underlying the protective effect of Tirzepatide (TIR), a dual glucose-dependent insulinotropic polypeptide receptor agonist (GIP-RA)/ GLP-1RA, against learning and memory disorders. METHODS: We investigated the effects of TIR on markers of neuronal growth (CREB and BDNF), apoptosis (BAX/Bcl2 ratio) differentiation (pAkt, MAP2, GAP43, and AGBL4), and insulin resistance (GLUT1, GLUT4, GLUT3 and SORBS1) in a neuroblastoma cell line (SHSY5Y) exposed to normal and high glucose concentration. The potential role on DNA methylation of genes involved in neuroprotection and epigenetic modulators of neuronal growth (miRNA 34a), apoptosis (miRNA 212), and differentiation (miRNA 29c) was also investigated. The cell proliferation was detected by measuring Ki-67 through flow cytometry. The data were analysed by SPSS IBM Version 23 or GraphPad Prism 7.0 software and expressed as the means ± SEM. Differences between the mean values were considered significant at a p-value of < 0.05. GraphPad Prism software was used for drawing figures. RESULTS: For the first time, it was highlighted: (a) the role of TIR in the activation of the pAkt/CREB/BDNF pathway and the downstream signaling cascade; (b) TIR efficacy in neuroprotection; (c) TIR counteracting of hyperglycemia and insulin resistance-related effects at the neuronal level. CONCLUSIONS: We demonstrated that TIR can ameliorate high glucose-induced neurodegeneration and overcome neuronal insulin resistance. Thus, this study provides new insight into the potential role of TIR in improving diabetes-related neuropathy.

Bridging the gap between GLP1-receptor agonists and cardiovascular outcomes: evidence for the role of tirzepatide.

Tirzepatide is a new drug targeting glucagon-like peptide 1(GLP1) and gastric inhibitory polypeptide (GIP) receptors. This drug has demonstrated great potential in improving the clinical outcomes of patients with type 2 diabetes. It can lead to weight loss, better glycemic control, and reduced cardiometabolic risk factors. GLP1 receptor agonists have been proven effective antidiabetic medications with possible cardiovascular benefits. Even though they have been proven to reduce the risk of major adverse cardiovascular events, their effectiveness in treating heart failure is unknown. Unlike traditional GLP1 receptor agonists, tirzepatide is more selective for the GIP receptor, resulting in a more balanced activation of these receptors. This review article discusses the possible mechanisms tirzepatide may use to improve cardiovascular health. That includes the anti-inflammatory effect, the ability to reduce cell death and promote autophagy, and also its indirect effects through blood pressure, obesity, and glucose/lipid metabolism. Additionally, tirzepatide may benefit atherosclerosis and lower the risk of major adverse cardiac events. Currently, clinical trials are underway to evaluate the safety and efficacy of tirzepatide in patients with heart failure. Overall, tirzepatide's dual agonism of GLP1 and GIP receptors appears to provide encouraging cardiovascular benefits beyond glycemic control, offering a potential new therapeutic option for treating cardiovascular diseases and heart failure.

Evidence that tirzepatide protects against diabetes-related cardiac damages.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are effective antidiabetic drugs with potential cardiovascular benefits. Despite their well-established role in reducing the risk of major adverse cardiovascular events (MACE), their impact on heart failure (HF) remains unclear. Therefore, our study examined the cardioprotective effects of tirzepatide (TZT), a novel glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) receptor agonist. METHODS: A three-steps approach was designed: (i) Meta-analysis investigation with the primary objective of assessing major adverse cardiovascular events (MACE) occurrence from major randomized clinical trials.; (ii) TZT effects on a human cardiac AC16 cell line exposed to normal (5 mM) and high (33 mM) glucose concentrations for 7 days. The gene expression and protein levels of primary markers related to cardiac fibrosis, hypertrophy, and calcium modulation were evaluated. (iii) In silico data from bioinformatic analyses for generating an interaction map that delineates the potential mechanism of action of TZT. RESULTS: Meta-analysis showed a reduced risk for MACE events by TZT therapy (HR was 0.59 (95% CI 0.40-0.79, Heterogeneity: r2 = 0.01, I2 = 23.45%, H2 = 1.31). In the human AC16 cardiac cell line treatment with 100 nM TZT contrasted high glucose (HG) levels increase in the expression of markers associated with fibrosis, hypertrophy, and cell death (p < 0.05 for all investigated markers). Bioinformatics analysis confirmed the interaction between the analyzed markers and the associated pathways found in AC16 cells by which TZT affects apoptosis, fibrosis, and contractility, thus reducing the risk of heart failure. CONCLUSION: Our findings indicate that TZT has beneficial effects on cardiac cells by positively modulating cardiomyocyte death, fibrosis, and hypertrophy in the presence of high glucose concentrations. This suggests that TZT may reduce the risk of diabetes-related cardiac damage, highlighting its potential as a therapeutic option for heart failure management clinical trials. Our study strongly supports the rationale behind the clinical trials currently underway, the results of which will be further investigated to gain insights into the cardiovascular safety and efficacy of TZT.

SGLT-2 inhibitors and in-stent restenosis-related events after acute myocardial infarction: an observational study in patients with type 2 diabetes.

BACKGROUND: No study evaluated the incidence of intra-stent restenosis (ISR)-related events in patients with type 2 diabetes (T2DM) and acute myocardial infarction (AMI) treated or not with sodium/glucose cotransporter 2 inhibitors (SGLT2i). METHODS: We recruited 377 patients with T2DM and AMI undergoing percutaneous coronary intervention (PCI). Among them, 177 T2DM were treated with SGLT2 inhibitors before PCI. The primary outcome was major adverse cardiovascular events (MACE) defined as cardiac death, re-infarction, and heart failure related to ISR. In patients without ISR, minimal lumen area and minimal lumen diameter were assessed by coronary CT-angiography at 1-year follow-up. RESULTS: Glycemic control was similar in SGLT2i-treated patients and never SGLT2i-users. The incidence of ISR-related MACE was higher in never SGLT2i-users compared with SGLT2i-treated patients, an effect independent of glycemic status (HR = 0.418, 95% CI = 0.241-0.725, P = 0.002) and observed also in the subgroup of patients with HbA1c < 7% (HR = 0.393, 95% CI = 0.157-0.984, P = 0.027). In patients without the event, the stent patency was greater in SGLT2i-treated patients compared with never SGLT2i-users at 1-year follow-up. CONCLUSIONS: SGLT2i treatment in T2DM is associated with a reduced incidence of ISR-related events, independently of glycemic control.

Multi-omics analysis reveals attenuation of cellular stress by empagliflozin in high glucose-treated human cardiomyocytes.

BACKGROUND: Sodium-glucose cotransporter 2 (SGLT2) inhibitors constitute the gold standard treatment for type 2 diabetes mellitus (T2DM). Among them, empagliflozin (EMPA) has shown beneficial effects against heart failure. Because cardiovascular diseases (mainly diabetic cardiomyopathy) are the leading cause of death in diabetic patients, the use of EMPA could be, simultaneously, cardioprotective and antidiabetic, reducing the risk of death from cardiovascular causes and decreasing the risk of hospitalization for heart failure in T2DM patients. Interestingly, recent studies have shown that EMPA has positive benefits for people with and without diabetes. This finding broadens the scope of EMPA function beyond glucose regulation alone to include a more intricate metabolic process that is, in part, still unknown. Similarly, this significantly increases the number of people with heart diseases who may be eligible for EMPA treatment. METHODS: This study aimed to clarify the metabolic effect of EMPA on the human myocardial cell model by using orthogonal metabolomics, lipidomics, and proteomics approaches. The untargeted and multivariate analysis mimicked the fasting blood sugar level of T2DM patients (hyperglycemia: HG) and in the average blood sugar range (normal glucose: NG), with and without the addition of EMPA. RESULTS: Results highlighted that EMPA was able to modulate and partially restore the levels of multiple metabolites associated with cellular stress, which were dysregulated in the HG conditions, such as nicotinamide mononucleotide, glucose-6-phosphate, lactic acid, FA 22:6 as well as nucleotide sugars and purine/pyrimidines. Additionally, EMPA regulated the levels of several lipid sub-classes, in particular dihydroceramide and triacylglycerols, which tend to accumulate in HG conditions resulting in lipotoxicity. Finally, EMPA counteracted the dysregulation of endoplasmic reticulum-derived proteins involved in cellular stress management. CONCLUSIONS: These results could suggest an effect of EMPA on different metabolic routes, tending to rescue cardiomyocyte metabolic status towards a healthy phenotype.

Targeting high glucose-induced epigenetic modifications at cardiac level: the role of SGLT2 and SGLT2 inhibitors.

BACKGROUND: Sodium-glucose co-transporters (SGLT) inhibitors (SGLT2i) showed many beneficial effects at the cardiovascular level. Several mechanisms of action have been identified. However, no data on their capability to act via epigenetic mechanisms were reported. Therefore, this study aimed to investigate the ability of SGLT2 inhibitors (SGLT2i) to induce protective effects at the cardiovascular level by acting on DNA methylation. METHODS: To better clarify this issue, the effects of empagliflozin (EMPA) on hyperglycemia-induced epigenetic modifications were evaluated in human ventricular cardiac myoblasts AC16 exposed to hyperglycemia for 7 days. Therefore, the effects of EMPA on DNA methylation of NF-κB, SOD2, and IL-6 genes in AC16 exposed to high glucose were analyzed by pyrosequencing-based methylation analysis. Modifications of gene expression and DNA methylation of NF-κB and SOD2 were confirmed in response to a transient SGLT2 gene silencing in the same cellular model. Moreover, chromatin immunoprecipitation followed by quantitative PCR was performed to evaluate the occupancy of TET2 across the investigated regions of NF-κB and SOD2 promoters. RESULTS: Seven days of high glucose treatment induced significant demethylation in the promoter regions of NF-kB and SOD2 with a consequent high level in mRNA expression of both genes. The observed DNA demethylation was mediated by increased TET2 expression and binding to the CpGs island in the promoter regions of analyzed genes. Indeed, EMPA prevented the HG-induced demethylation changes by reducing TET2 binding to the investigated promoter region and counteracted the altered gene expression. The transient SGLT2 gene silencing prevented the DNA demethylation observed in promoter regions, thus suggesting a role of SGLT2 as a potential target of the anti-inflammatory and antioxidant effect of EMPA in cardiomyocytes. CONCLUSIONS: In conclusion, our results demonstrated that EMPA, mainly acting on SGLT2, prevented DNA methylation changes induced by high glucose and provided evidence of a new mechanism by which SGLT2i can exert cardio-beneficial effects.

Glycated ACE2 reduces anti-remodeling effects of renin-angiotensin system inhibition in human diabetic hearts.

BACKGROUND: High glycated-hemoglobin (HbA1c) levels correlated with an elevated risk of adverse cardiovascular outcomes despite renin-angiotensin system (RAS) inhibition in type-2 diabetic (T2DM) patients with reduced ejection fraction. Using the routine biopsies of non-T2DM heart transplanted (HTX) in T2DM recipients, we evaluated whether the diabetic milieu modulates glycosylated ACE2 (GlycACE2) levels in cardiomyocytes, known to be affected by non-enzymatic glycosylation, and the relationship with glycemic control. OBJECTIVES: We investigated the possible effects of GlycACE2 on the anti-remodeling pathways of the RAS inhibitors by evaluating the levels of Angiotensin (Ang) 1-9, Ang 1-7, and Mas receptor (MasR), Nuclear-factor of activated T-cells (NFAT), and fibrosis in human hearts. METHODS: We evaluated 197 first HTX recipients (107 non-T2DM, 90 T2DM). All patients were treated with angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) at hospital discharge. Patients underwent clinical evaluation (metabolic status, echocardiography, coronary CT-angiography, and endomyocardial biopsies). Biopsies were used to evaluate ACE2, GlycACE2, Ang 1-9, Ang 1-7, MasR, NAFT, and fibrosis. RESULTS: GlycACE2 was higher in T2DM compared tonon-T2DM cardiomyocytes. Moreover, reduced expressions of Ang 1-9, Ang 1-7, and MasR were observed, suggesting impaired effects of RAS-inhibition in diabetic hearts. Accordingly, biopsies from T2DM recipients showed higher fibrosis than those from non-T2DM recipients. Notably, the expression of GlycACE2 in heart biopsies was strongly dependent on glycemic control, as reflected by the correlation between mean plasma HbA1c, evaluated quarterly during the 12-month follow-up, and GlycACE2 expression. CONCLUSION: Poor glycemic control, favoring GlycACE2, may attenuate the cardioprotective effects of RAS-inhibition. However, the achievement of tight glycemic control normalizes the anti-remodeling effects of RAS-inhibition. TRIAL REGISTRATION: https://clinicaltrials.gov/ NCT03546062.

Sodium-glucose cotransporter-2 (SGLT2) expression in diabetic and non-diabetic failing human cardiomyocytes.

This study aimed at investigating the SGLT2 expression in human cardiomyocytes. Human studies evaluating cardiomyocyte SGLT2s expression are limited. To better clarify this issue, SGLT2 protein expression was assessed in human hearts of diabetic and non-diabetic patients, and in AC16 human cardiomyocyte cell line. A prospective study with a follow-up of patients who underwent their first heart transplant (HTX) was performed. Explanted heart, basal (1 week after HTX), and final (48 weeks after HTX) endomyocardial biopsies (EMBs) from patients were evaluated for SGLT2 occurrence in cardiomyocyte with immunohistochemistry, immunofluorescence and SGLT2 quantization with both real-time reverse transcription-polymerase chain reaction and Western blot analysis. The immunofluorescence co-localization of SGLT2 in cardiomyocyte evidenced that an increased expression in the explanted heart from diabetic patients compared to non-diabetic (p < 0.001). In all final EMBs from diabetic patients, the expression of SGLT2 in cardiomyocyte was increased compared to non-diabetic (p < 0.01). This evidence was confirmed by Western blot analysis of SGLT2 protein. In addition, PCR analysis revealed very low mRNA levels in basal EMBs from diabetic and non-diabetic patients (p = NS), whereas final EMBs from diabetic patients showed higher SGLT2 mRNA levels in diabetic compared to non-diabetic patients (p < 0.05). Cultured human cardiomyocytes exposed to high-glucose showed increased expression of SGLT2 protein compared to cells exposed to normal glucose (p < 0.05). The presence of SGLT2 in cardiomyocytes supports the hypothesis of SGLT2i-mediated impact on metabolic pathways within cardiomyocytes. Moreover, metabolic disorders linked to diabetes may lead promptly to upregulation of SGLT2 levels in human cardiomyocytes.

Angiotensin receptor/Neprilysin inhibitor effects in CRTd non-responders: From epigenetic to clinical beside.

OBJECTIVES: We evaluated whether Angiotensin receptor/Neprilysin inhibitors (ARNI) reduce heart failure (HF) hospitalizations and deaths in cardiac resynchronization therapy with defibrillator (CRTd) non-responders patients at 12 months of follow-up, modulating microRNAs (miRs) implied in adverse cardiac remodeling. BACKGROUND: adverse cardiac remodeling characterized by left ventricle ejection fraction (LVEF) reduction, left ventricular end-systolic volume (LVESv) increase, and the 6-minute walking test (6MWT) reduction are relevant pathological mechanisms in CRTd non-responders and could be linked to changes in miRNAs (miRs), regulating cardiac fibrosis, apoptosis, and hypertrophy. METHODS: miRs levels and clinical outcomes (LVEF, cardiac deaths, and 6MWT) were evaluated at baseline and one year of follow-up in CRTd non-responders divided into ARNI-users and Non-ARNI users. RESULTS: At baseline, there were no differences in levels of inflammatory markers, miR-18, miR-145, and miR-181 (p > 0.05) between Non-ARNI users (n 106) and ARNI-users (n 312). At one year of follow-up, ARNI-users vs. Non-ARNI users showed lowest inflammatory markers (p < 0.01) and miR-181 levels (p < 0.01) and higher values of miR-18 (p < 0.01)and miR-145 (p < 0.01). At one year of follow-up, ARNI-users had a higher increase of LVEF (p < 0.01) and 6MWT (p < 0.01) along with a more significant reduction of LVESv (p < 0.01) compared to Non-ARNI users. Cox regression analysis evidenced that ARNI-based therapies increase the probability of anti-remodeling effects of CRTd. Based on symptomatic improvements, echocardiographic and functional classification improvements, 37 (34.9%) patients among ARNI-users became responders, while only twenty (6.4%) patients became responders among Non-ARNi-users. CONCLUSIONS: ARNI might influence epigenetic mechanisms modulating miRs implicated in the adverse cardiac remodeling responses to CRTd.

New insight in molecular mechanisms regulating SIRT6 expression in diabetes: Hyperglycaemia effects on SIRT6 DNA methylation.

Conflicting data are reported on the relationship between hyperglycaemia, diabetes and SIRT6 expression. To elucidate hyperglycaemia-induced molecular mechanisms regulating SIRT6 expression, the effect of hyperglycaemia on DNA methylation and SIRT6 expression has been evaluated in human aortic endothelial cells exposed to high glucose. DNA methylation of SIRT6 and any potential clinical implication was also evaluated in type 2 diabetic patients and compared with healthy controls. Endothelial cells exposed to high glucose showed lower methylation levels in SIRT6 promoter and increased SIRT6 and TET2 expression. The high glucose-induced epigenetic changes persisted after 48 h of glucose normalization. Diabetic patients showed lower levels of SIRT6 DNA methylation compared with nondiabetic patients. SIRT6 DNA methylation levels inversely correlated with plasma glucose. Our results firstly demonstrate the involvement of epigenetic mechanisms in regulating SIRT6 expression. Further experiments are necessary to clarify metabolic memory mechanisms driving to diabetic complications and how SIRT6 is potentially involved.

Glycated ACE2 receptor in diabetes: open door for SARS-COV-2 entry in cardiomyocyte.

RATIONALE: About 50% of hospitalized coronavirus disease 2019 (COVID-19) patients with diabetes mellitus (DM) developed myocardial damage. The mechanisms of direct SARS-CoV-2 cardiomyocyte infection include viral invasion via ACE2-Spike glycoprotein-binding. In DM patients, the impact of glycation of ACE2 on cardiomyocyte invasion by SARS-CoV-2 can be of high importance. OBJECTIVE: To evaluate the presence of SARS-CoV-2 in cardiomyocytes from heart autopsy of DM cases compared to Non-DM; to investigate the role of DM in SARS-COV-2 entry in cardiomyocytes. METHODS AND RESULTS: We evaluated consecutive autopsy cases, deceased for COVID-19, from Italy between Apr 30, 2020 and Jan 18, 2021. We evaluated SARS-CoV-2 in cardiomyocytes, expression of ACE2 (total and glycosylated form), and transmembrane protease serine protease-2 (TMPRSS2) protein. In order to study the role of diabetes on cardiomyocyte alterations, independently of COVID-19, we investigated ACE2, glycosylated ACE2, and TMPRSS2 proteins in cardiomyocytes from DM and Non-DM explanted-hearts. Finally, to investigate the effects of DM on ACE2 protein modification, an in vitro glycation study of recombinant human ACE2 (hACE2) was performed to evaluate the effects on binding to SARS-CoV-2 Spike protein. The authors included cardiac tissue from 97 autopsies. DM was diagnosed in 37 patients (38%). Fourth-seven out of 97 autopsies (48%) had SARS-CoV-2 RNA in cardiomyocytes. Thirty out of 37 DM autopsy cases (81%) and 17 out of 60 Non-DM autopsy cases (28%) had SARS-CoV-2 RNA in cardiomyocytes. Total ACE2, glycosylated ACE2, and TMPRSS2 protein expressions were higher in cardiomyocytes from autopsied and explanted hearts of DM than Non-DM. In vitro exposure of monomeric hACE2 to 120 mM glucose for 12 days led to non-enzymatic glycation of four lysine residues in the neck domain affecting the protein oligomerization. CONCLUSIONS: The upregulation of ACE2 expression (total and glycosylated forms) in DM cardiomyocytes, along with non-enzymatic glycation, could increase the susceptibility to COVID-19 infection in DM patients by favouring the cellular entry of SARS-CoV2.

Incretin drugs effect on epigenetic machinery: New potential therapeutic implications in preventing vascular diabetic complications.

The effect of GLP-1R agonists on DNA methylation levels of NF-κB and SOD2 genes in human aortic endothelial cells exposed to high glucose and in diabetic patients treated and not with incretin-based drugs, was evaluated. Methylation levels, mRNA and protein expression of NF-κB and SOD2 genes were measured in human endothelial cells exposed to high glucose for 7 days and treated with GLP-1R agonists. Methylation status of NF-κB and SOD2 promoter was also analyzed in 128 diabetics and 116 nondiabetics and correlated with intima media thickness (ITM), an early marker of atherosclerotic process. Cells exposed to high glucose showed lower NF-κB and SOD2 methylation levels, increased NF-κB and reduced SOD2 expression compared to normal glucose cells. Co-treatment with GLP-1 agonists prevented methylation and genes expression changes induced by high glucose. Both high glucose and incretins exposure increased DNA methyltransferases and demethylases levels. In diabetics, incretin treatment resulted a significant predictor of NF-κB DNA methylation, independently of age, sex, body mass index (BMI), glucose and plasma lipid levels. NF-κB DNA methylation inversely correlated with IMT after adjusting for multiple covariates. Our results firstly provide new evidences of an additional mechanism by which incretin drugs could prevent vascular diabetic complications.

SGLT-2 inhibitors reduce the risk of cerebrovascular/cardiovascular outcomes and mortality: A systematic review and meta-analysis of retrospective cohort studies.

Despite Sodium-glucose co-transporter-2 (SGLT2) inhibitors have been associated with a reduced risk of heart failure in patients with type 2 diabetes mellitus (T2DM), the effect observed for other cardiovascular (CV) and cerebrovascular outcomes differed among clinical trials. Different observational studies have investigated the effects of SGLT2 inhibitors on these outcomes and mortality. The present meta-analysis aimed to assess the effects of SGLT2 inhibitors on the risk of CV (major adverse CV event - MACE, non-fatal myocardial infarction, or hospitalization for heart failure) and cerebrovascular (stroke) outcomes. A systematic review was conducted in Pubmed from January 1, 2012 to November 31, 2020. Only retrospective cohort studies including as control group users of dipeptidyl peptidase-4 (DPP-4) inhibitors or non-SGLT2 inhibitors were retained and analysed separately. A random effect meta-analysis approach was used. This study followed the PRISMA statement. Of the 158 references identified, 20 articles were selected for meta-analysis, of which 13 considered the comparison with DPP-4 inhibitors and 7 the comparison with non-SGLT2 inhibitors. The pooled intention-to-treat analysis showed a reduced risk of stroke with SGLT2 inhibitors compared to DPP-4 inhibitors (Hazard ratio HR, 0.89; 95%CI, 0.82-0.96; I2 = 25%; p = 0.25) and non-SGLT2 inhibitors (HR, 0.83; 95%CI, 0.77-0.91; I2 = 11%; p = 0.34). Finally, SGLT2 inhibitors were also associated with a reduced risk of CV outcomes and mortality in all comparisons. Our data support contemporary society recommendations to prioritise the use of SGLT2 inhibitors in patients with T2DM and at high risk for CV complications.

SARS-COV-2 colonizes coronary thrombus and impairs heart microcirculation bed in asymptomatic SARS-CoV-2 positive subjects with acute myocardial infarction.

BACKGROUND: The viral load of asymptomatic SAR-COV-2 positive (ASAP) persons has been equal to that of symptomatic patients. On the other hand, there are no reports of ST-elevation myocardial infarction (STEMI) outcomes in ASAP patients. Therefore, we evaluated thrombus burden and thrombus viral load and their impact on microvascular bed perfusion in the infarct area (myocardial blush grade, MBG) in ASAP compared to SARS-COV-2 negative (SANE) STEMI patients. METHODS: This was an observational study of 46 ASAP, and 130 SANE patients admitted with confirmed STEMI treated with primary percutaneous coronary intervention and thrombus aspiration. The primary endpoints were thrombus dimension + thrombus viral load effects on MBG after PPCI. The secondary endpoints during hospitalization were major adverse cardiovascular events (MACEs). MACEs are defined as a composite of cardiovascular death, nonfatal acute AMI, and heart failure during hospitalization. RESULTS: In the study population, ASAP vs. SANE showed a significant greater use of GP IIb/IIIa inhibitors and of heparin (p < 0.05), and a higher thrombus grade 5 and thrombus dimensions (p < 0.05). Interestingly, ASAP vs. SANE patients had lower MBG and left ventricular function (p < 0.001), and 39 (84.9%) of ASAP patients had thrombus specimens positive for SARS-COV-2. After PPCI, a MBG 2-3 was present in only 26.1% of ASAP vs. 97.7% of SANE STEMI patients (p < 0.001). Notably, death and nonfatal AMI were higher in ASAP vs. SANE patients (p < 0.05). Finally, in ASAP STEMI patients the thrombus viral load was a significant determinant of thrombus dimension independently of risk factors (p < 0.005). Thus, multiple logistic regression analyses evidenced that thrombus SARS-CoV-2 infection and dimension were significant predictors of poorer MBG in STEMI patients. Intriguingly, in ASAP patients the female vs. male had higher thrombus viral load (15.53 ± 4.5 vs. 30.25 ± 5.51 CT; p < 0.001), and thrombus dimension (4.62 ± 0.44 vs 4.00 ± 1.28 mm2; p < 0.001). ASAP vs. SANE patients had a significantly lower in-hospital survival for MACE following PPCI (p < 0.001). CONCLUSIONS: In ASAP patients presenting with STEMI, there is strong evidence towards higher thrombus viral load, dimension, and poorer MBG. These data support the need to reconsider ASAP status as a risk factor that may worsen STEMI outcomes.

MicroRNA-33 and SIRT1 influence the coronary thrombus burden in hyperglycemic STEMI patients.

Primary percutaneous coronary intervention (PPCI) is a pivotal treatment in ST-segment elevation myocardial infarction (STEMI) patients. However, in hyperglycemic-STEMI patients, the incidence of death is still significant. Here, the involvement of sirtuin 1 (SIRT1) and miR33 on the pro-inflammatory/pro-coagulable state of the coronary thrombus was investigated. Moreover, 1-year outcomes in hyperglycemic STEMI in patients subjected to thrombus aspiration before PPCI were evaluated. Results showed that hyperglycemic thrombi displayed higher size and increased miR33, reactive oxygen species, and pro-inflammatory/pro-coagulable markers. Conversely, the hyperglycemic thrombi showed a lower endothelial SIRT1 expression. Moreover, in vitro experiments on endothelial cells showed a causal effect of SIRT1 modulation on the pro-inflammatory/pro-coagulative state via hyperglycemia-induced miR33 expression. Finally, SIRT1 expression negatively correlated with STEMI outcomes. These observations demonstrate the involvement of the miR33/SIRT1 pathway in the increased pro-inflammatory and pro-coagulable state of coronary thrombi in hyperglycemic STEMI patients.

Pericoronary fat inflammation and Major Adverse Cardiac Events (MACE) in prediabetic patients with acute myocardial infarction: effects of metformin.

BACKGROUND/OBJECTIVES: Pericoronary adipose tissue inflammation might lead to the development and destabilization of coronary plaques in prediabetic patients. Here, we evaluated inflammation and leptin to adiponectin ratio in pericoronary fat from patients subjected to coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI). Furthermore, we compared the 12-month prognosis of prediabetic patients compared to normoglycemic patients (NG). Finally, the effect of metformin therapy on pericoronary fat inflammation and 12-months prognosis in AMI-prediabetic patients was also evaluated. METHODS: An observational prospective study was conducted on patients with first AMI referred for CABG. Participants were divided in prediabetic and NG-patients. Prediabetic patients were divided in two groups; never-metformin-users and current-metformin-users receiving metformin therapy for almost 6 months before CABG. During the by-pass procedure on epicardial coronary portion, the pericoronary fat was removed from the surrounding stenosis area. The primary endpoints were the assessments of Major-Adverse-Cardiac-Events (MACE) at 12-month follow-up. Moreover, inflammatory tone was evaluated by measuring pericoronary fat levels of tumor necrosis factor-α (TNF-α), sirtuin 6 (SIRT6), and leptin to adiponectin ratio. Finally, inflammatory tone was correlated to the MACE during the 12-months follow-up. RESULTS: The MACE was 9.1% in all prediabetic patients and 3% in NG-patients. In prediabetic patients, current-metformin-users presented a significantly lower rate of MACE compared to prediabetic patients never-metformin-users. In addition, prediabetic patients showed higher inflammatory tone and leptin to adiponectin ratio in pericoronary fat compared to NG-patients (P < 0.001). Prediabetic never-metformin-users showed higher inflammatory tone and leptin to adiponectin ratio in pericoronary fat compared to current-metformin-users (P < 0.001). Remarkably, inflammatory tone and leptin to adiponectin ratio was significantly related to the MACE during the 12-months follow-up. CONCLUSION: Prediabetes increase inflammatory burden in pericoronary adipose tissue. Metformin by reducing inflammatory tone and leptin to adiponectin ratio in pericoronary fat may improve prognosis in prediabetic patients with AMI. Trial registration Clinical Trial NCT03360981, Retrospectively Registered 7 January 2018.