SIRT1 suppresses cardiomyocyte apoptosis in diabetic cardiomyopathy: An insight into endoplasmic reticulum stress response mechanism

BACKGROUND

Endoplasmic reticulum (ER) stress-dependent apoptosis had been shown to occur in the hearts of people with diabetes, although the exact mechanisms are unclear. Sirtuin 1 (SIRT1), a nicotinamide adenine dinucleotide NAD(+)-dependent deacetylase, is known to play a role in diabetes-related complications as well as ER-stress. Therefore, we investigated the relationship between Sirtuin 1 (SIRT1) and ER stress-induced apoptosis in H9C2 cardiomyocyte.

METHODS

Diabetic rats were established by a single intraperitoneal injection of streptozotocin (STZ; 50mg/kg) with high-fat diet. For in vitro analysis, rat derived H9C2 cardiomyocytes were cultured. Cardiac function was assessed by Doppler, and SIRT1 as well as ER stress related protein expressions were measured by immunohistochemistry and western blotting. Cultured cells were exposed to advanced glycation end products (AGEs) (400μg/mL) for inducing ER stress and apoptosis. Cell apoptosis were detected by flow cytometry.

RESULTS

In vivo, ER stress was enhanced in the cardiomyocytes of diabetic rats without any treatments. A SIRT1 activator, resveratrol, could significantly restore cardiac function, reduce cardiomyocyte apoptosis, and ameliorate ER stress. In vitro, we showed that apoptosis and ER stress increased after AGE stimulation when SIRT1 expression was downregulated by short interfering RNA (siRNA) (p<0.05). However, resveratrol (10μM) restored SIRT1 levels in cardiomyocytes and markedly reduced ER stress-mediated apoptosis.

CONCLUSION

SIRT1 may attenuate ER stress-induced cardiomyocyte apoptosis via PERK/eIF2α, ATF6/CHOP, and IRE1α/JNK-mediated pathways. This study may provide insights into a novel underlying mechanism and a strategy for treating diabetic cardiomyopathy.

Resveratrol ameliorates diabetic vascular inflammation and macrophage infiltration in db/db mice by inhibiting the NF-κB pathway

In this study, resveratrol (RSV) - a potent sirtuin 1 activator - was found to have beneficial effects on glucolipid metabolism and improve inflammatory mediators and markers of oxidative stress. Diabetic (db/db) mice and non-diabetic C57BL/6J mice were used in the study. The db/db mice were treated with or without 0.3% RSV mixed with chow for 8 weeks. Dietary RSV significantly lowered blood glucose, plasma lipid and free fatty acid levels in db/db mice. RSV markedly inhibited the expression of intercellular adhesion molecule-1 (ICAM-1), endothelial vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) in the aorta and the blood plasma of db/db mice (p < 0.05). Levels of mac-3-positive macrophages (measure of the infiltration of activated macrophages) were lower in RSV-treated diabetic mice than in their untreated counterparts (p < 0.05). RSV treatment reduced the activity of the transcriptional regulator nuclear factor kappa B (NF-κB) in aortic tissues (p < 0.05). Thus, RSV treatment reduced ICAM-1, VCAM-1 and MCP-1 expression in the aorta and ICAM-1, VCAM-1 and MCP-1 levels in the plasma of diabetic mice. Since dietary supplementation with RSV also reduced NF-κB activities in the aorta, the therapeutic effects of RSV might be associated with the downregulation of NF-κB.

Enhancement in efferocytosis of oxidized low-density lipoprotein-induced apoptotic RAW264.7 cells through Sirt1-mediated autophagy

Macrophages play a key role in atherosclerotic plaque formation and rupture. These phagocytic cells are important in the scavenging of modified lipoproteins, unwanted or dead cells and cellular debris through efferocytosis. Sirtuin1 (Sirt1), a member of the conserved sirtuin family and a key regulator in the progression of atherosclerosis exerts protective effects by regulating autophagy, a well-known survival mechanism. Inhibition of autophagy may also result in defective efferocytosis. This study aimed to investigate the effect of Sirt1 on the efferocytosis of oxidized low-density lipoprotein (ox-LDL)-induced apoptotic RAW264.7 cells through upregulation of autophagy. The apoptotic cells were incubated with high and low concentrations of Sirt1 activator resveratrol (RSV) and Sirt1 inhibitor nicotinamide (NAM) as well as autophagy inhibitor 3-methyl-adenine (3-MA) + low concentration RSV. Apoptosis was determined by flow cytometry (FCM) of annexin-V/propidium iodide (AV/PI) dual staining. Total proteins were extracted and protein levels were detected through western blot analysis. The ox-LDL uptake and efferocytosis of apoptotic RAW264.7 cells were detected by oil red O staining and calculation of the phagocytic index of apoptotic RAW264.7 cells. The expression of Sirt1 and autophagy marker proteins was simultaneously increased with the stimulation of low concentration RSV (all P<0.05) and decreased in low and high NAM groups (all P<0.05), compared with the control group. Efferocytosis was highest in the low concentration RSV group (P<0.001) and relatively lower in the low and high concentration NAM groups (both P<0.05) compared with the control group, which was similar to the change in the expression of Sirt1 and autophagy marker proteins. The results showed that the efferocytosis of apoptotic RAW264.7 cells was significantly improved with the upregulation of Sirt1‑mediated autophagy. Therefore, Sirt1 may serve as a novel therapeutic target for the treatment of atherosclerosis.

Resveratrol suppresses oxidised low-density lipoprotein-induced macrophage apoptosis through inhibition of intracellular reactive oxygen species generation, LOX-1, and the p38 MAPK pathway

BACKGROUND/AIM

Resveratrol (RSV) may have therapeutic potential for various diseases. Here we investigated the effect of RSV on oxidised low-density lipoprotein- (ox-LDL) induced apoptosis in RAW264.7 macrophages.

METHODS

Apoptosis of macrophages following incubation with ox-LDL (with or without RSV pre-treatment) was detected by flow cytometry. Western blotting was used to assess the protein expression of Bax, Bcl-2, and caspase-3 as well as ox-LDL receptor 1 (LOX-1) and p38 mitogen-activated protein kinase (MAPK) phosphorylation. Reactive oxygen species (ROS) generation was evaluated by 2', 7'-dichlorofluorescein diacetate, and JC-1 probe was used to determine the mitochondrial transmembrane potential of cells.

RESULTS

Ox-LDL significantly reduced viability and increased the rate of apoptosis (P < 0.05) in RAW264.7 cells. However, pre-treatment with RSV resulted in a remarkable decrease in this apoptotic effect. Moreover, ox-LDL caused the up-regulation of Bax and the down-regulation of Bcl-2, as well as the activation of caspase-3. Expression of LOX-1, phosphorylation of p38 MAPK, and intracellular ROS production also increased after ox-LDL stimulation. Strikingly, these effects were abolished by pre-treatment of cells with RSV.

CONCLUSION

RSV suppresses ox-LDL-induced macrophage apoptosis. These beneficial effects might be exerted through inhibition of ROS generation, LOX-1, and the p38 MAPK signalling pathway.

The protective effect of fasudil on the structure and function of cardiac mitochondria from rats with type 2 diabetes induced by streptozotocin with a high-fat diet is mediated by the attenuation of oxidative stress

Dysfunction of cardiac mitochondria appears to play a substantial role in cardiomyopathy or myocardial dysfunction and is a promising therapeutic target for many cardiovascular diseases. We investigated the effect of the Rho/Rho-associated protein kinase (ROCK) inhibitor fasudil on cardiac mitochondria from rats in which diabetes was induced by a combination of streptozotocin (STZ) and a sustained high-fat diet. Eight weeks after diabetes was induced by a single intraperitoneal injection of 50 mg/kg STZ followed by a sustained high-fat diet, either fasudil (5 mg/kg bid) or equivalent volumes of saline (control) were administered over four weeks. Fasudil significantly protected against the histopathologic changes of cardiac mitochondria in diabetic rats. Fasudil significantly reduced the abundances of the Rho A, ROCK 1, and ROCK 2 proteins, restored the activities of succinate dehydrogenase (SDH) and monoamine oxidase (MAO) in cardiac mitochondria, inhibited the opening of the mitochondrial permeability transition pore, and decreased the total antioxidant capacity, as well as levels of malonyldialdehyde, hydroxy radical, reduced glutathione, and superoxide dismutase in heart. Fasudil improved the structures of cardiac mitochondria and increased both SDH and MAO activities in cardiac mitochondria. These beneficial effects may be associated with the attenuation of oxidative stress caused by fasudil treatment.

Elevated plasma level of pentraxin-3 predicts in-hospital and 30-day clinical outcomes in patients with non-ST-segment elevation myocardial infarction who have undergone percutaneous coronary intervention

OBJECTIVES

This investigation explored the short-term prognostic value of pentraxin-3 (PTX3) levels in patients with non-ST-segment elevation myocardial infarction (NSTEMI) treated by percutaneous coronary intervention (PCI).

METHODS

We measured plasma levels of PTX3 and other biomarkers in 525 PCI-treated NSTEMI patients (mean age, 57.7 years; 328 males). The associations of PTX3 levels with cardiac events and cardiac deaths occurring within 30 days of discharge were evaluated with multivariable Cox proportional hazard models.

RESULTS

Renal function, diabetes prevalence, systolic blood pressure, heart rate and ejection fraction differed significantly in the high PTX3 (≥3.0 ng/ml, n = 107) and low PTX3 (<3.0 ng/ml, n = 418) groups (all p < 0.05). Plasma PTX3 levels were correlated with high-sensitivity C-reactive protein, troponin T and N-terminal pro-B-type natriuretic peptide in NSTEMI patients (all p < 0.05). Kaplan-Meier analysis showed in-hospital and 30-day cardiac events and deaths were higher in the high PTX3 group (both p < 0.01). Elevated PTX3 was an independent predictor of 30-day cardiac events (95% CI 1.09-1.68; p = 0.006) and mortality (95% CI 1.18-2.15; p = 0.002).

CONCLUSIONS

An elevated plasma level of PTX3 predicts 30-day cardiac events and mortality in PCI-treated NSTEMI patients.

Salidroside decreases atherosclerotic plaque formation in low-density lipoprotein receptor-deficient mice

Salidroside is isolated from Rhodiola rosea and is one of the main active components in Rhodiola species. The present study was designed to evaluate the effects of Salidroside on atherosclerotic plaque formation in high-fat diet-(HFD-) fed female LDL receptor knockout (LDLr(-/-)) mice. LDLr(-/-) mice fed an atherogenic HFD for 12 weeks were divided into two groups. One group was administered Salidroside (50 mg/kg/oral gavage) daily for 8 weeks, while the control group was administered saline. Salidroside treatment reduced serum lipids levels and the plaque area through the arch to the abdominal aorta. Furthermore, Salidroside improved macrophage content and enhanced collagen and smooth muscle cells contents in the aortic sinus. These changes were associated with reduced MCP-1, VCAM-1, and VCAM-1 protein expression in atherosclerotic aortas. All these results suggest that Salidroside decreases atherosclerotic plaques formation via effects on lipid lowering and anti-inflammation in HFD-fed LDLr(-/-) mice.

Significance of fragmented QRS complexes for identifying culprit lesions in patients with non-ST-elevation myocardial infarction: a single-center, retrospective analysis of 183 cases

BACKGROUND

Fragmented QRS (fQRS) complexes are novel electrocardiographic signals, which reflect myocardial conduction delays in patients with coronary artery disease (CAD). The importance of fQRS complexes in identifying culprit vessels was evaluated in this retrospective study.

METHODS

A 12-lead surface electrocardiogram was obtained in 183 patients who had non-ST-elevation myocardial infarction (NSTEMI) and subsequently underwent coronary angiography (CAG). On the basis of the frequency of fQRS complexes, indices such as sensitivity, specificity, positive and negative predictive values, and likelihood ratio were evaluated to determine the ability of fQRS complexes to identify the culprit vessels.

RESULTS

Among the patients studied, elderly patients (age ≥ 65 years) and those with diabetes had a significantly higher frequency of fQRS complexes (p = 0.005, p = 0.003, respectively). The fQRS complexes recorded in the 4 precordial leads had the highest specificity (81.8%) for identifying the culprit vessel (left anterior descending artery). However, the specificity of fQRS complexes to identify lesions in the left circumflex and right coronary arteries was lower for the inferior and lateral leads than for the limb leads (65.5% versus 71.7%); however, the limb leads had higher sensitivity (92.3% versus 89.4%). And the total sensitivity and specificity of fQRS (77.1% and 71.5%) were higher than those values for ischemic T-waves.

CONCLUSIONS

The frequency of fQRS complexes was higher in elderly and diabetic patients with NSTEMI. The frequency of fQRS complexes recorded in each of the ECG leads can be used to identify culprit vessels in patients with NSTEMI.

Pathogenic mechanism of a catecholaminergic polymorphic ventricular tachycardia causing-mutation in cardiac calcium release channel RyR2

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a condition that is characterized by an abnormal heart rhythm in response to physical or emotional stress. The majority CPVT patients carry mutations in the RYR2 gene that encodes the calcium release channel/ryanodine receptor (RyR2) in cardiomyocytes. The pathogenic mechanisms that account for the clinical phenotypes of CPVT are still elusive. We have identified a de novo mutation, A165D, from a CPVT patient. We found that CPVT phenotypes are recapitulated in A165D knock-in mice. The mutant RyR2 channels enhanced sarcoplasmic reticulum Ca2+ release, triggered delayed afterdepolarization in cardiomyocytes. Structural analysis revealed that the A165D mutation is located in a loop that is involved in inter-subunit interactions in the RyR2 tetrameric structure, it disrupted conformational stability of the RyR2, which favored a closed-to-open state transition, resulting in a leaky channel. The loop also harbors several other CPVT mutations, which suggests a common pathogenic molecular mechanism of CPVT-causing mutations. Our data illustrated disease-relevant functional defects and provide a deeper mechanistic understanding of a life-threatening cardiac arrhythmia.

Salidroside protects against foam cell formation and apoptosis, possibly via the MAPK and AKT signaling pathways

BACKGROUND

Foam cell formation and apoptosis are closely associated with atherosclerosis pathogenesis. We determined the effect of salidroside on oxidized low-density lipoprotein (ox-LDL)-induced foam cell formation and apoptosis in THP1 human acute monocytic leukemia cells and investigated the associated molecular mechanisms.

METHODS

THP1-derived macrophages were incubated with salidroside for 5 h and then exposed to ox-LDL for 24 h to induce foam cell formation. Cytotoxicity, lipid deposition, apoptosis, and the expression of various proteins were tested using the CCK8 kit, Oil Red O staining, flow cytometry, and western blotting, respectively.

RESULTS

Ox-LDL treatment alone promoted macrophage-derived foam cell formation, while salidroside treatment alone inhibited it (p < 0.05). The number of early/late apoptotic cells decreased with salidroside treatment in a dose-dependent manner (p < 0.05). Salidroside dramatically upregulated nuclear factor erythroid 2-related factor 2, but had no effect on heme oxygenase-1 expression; moreover, it markedly downregulated ox-LDL receptor 1 and upregulated ATP-binding cassette transporter A1. Salidroside also obviously decreased the phosphorylation of JNK, ERK, p38 MAPK, and increased that of Akt. However, the total expression of these proteins was not affected.

CONCLUSION

Based on our findings, we speculate that salidroside can suppress ox-LDL-induced THP1-derived foam cell formation and apoptosis, partly by regulating the MAPK and Akt signaling pathways.

Salidroside protects against cardiomyocyte apoptosis and ventricular remodeling by AKT/HO-1 signaling pathways in a diabetic cardiomyopathy mouse model

BACKGROUND

Diabetic cardiomyopathy is characterized by both systolic and diastolic dysfunction due to decreased contractility, as well as reduced compliance of the myocardium. Oxidative stress plays a significant role in diabetes mellitus and its cardiovascular complications. Salidroside, a glucoside of the phenylpropanoid tyrosol, reportedly increases the levels of the antioxidative enzymes, nuclear factor erythroid 2-related factor 2, and heme oxygenase-1 (HO-1) to counteract oxidative stress; however, the underlying mechanisms are poorly understood.

PURPOSE

Here we investigate the potential cardio-protective effects of salidroside and its mechanism in a diabetic animal model.

METHODS

Male db/m, db/db, and age-matched wild-type mice were treated with salidroside at low dose (0.025 mg/kg) or high dose (0.05 mg/kg) by gavage every day for 12 weeks. Cardiac function and structure were assessed by echocardiography and histopathological examination. H9C2 cardiomyocytes were exposed in vitro to advanced glycosylation end products (400 μg/ml) and treated with salidroside (0.1, 1, or 10 μM). The expression of signaling-related genes were explored by western blotting and real-time PCR.

RESULTS

Salidroside treatment significantly improved diabetes-induced cardiac dysfunction, hypertrophy, and fibrosis in vivo. Mechanistically, salidroside markedly up-regulates HO-1 expression by activation of the AKT signaling pathway.

CONCLUSION

Salidroside protects against cardiomyocyte apoptosis and ventricular remodeling in diabetic mice. This cardio-protective effect of salidroside is dependent on AKT signaling activation.

Salidroside Protects Against Advanced Glycation End Products-Induced Vascular Endothelial Dysfunction

BACKGROUND Salidroside, the major active compound in Rhodiola, has been reported to provide beneficial effects on cardiovascular diseases, but its effects on diabetes-induced vascular endothelial dysfunction are less known. Here, we examined the protective effects of salidroside on endothelial function in diabetes and explored the potential underlying mechanism. MATERIAL AND METHODS First, we assessed the endothelium-dependent relaxation response to acetylcholine, with or without salidroside treatment, in aortas isolated from Sprague-Dawley rats. Then, cell viability, oxidative biomarkers, and protein expression were tested to determine the effect of salidroside treatment on human umbilical vein endothelial cells (HUVECs) in vitro. RESULTS Advanced glycation end product (AGE)-induced endothelial dysfunction was significantly improved by salidroside treatment (P<0.05), as shown by a reduced relaxation response to the vasodilator acetylcholine. Further, incubation with salidroside restored NO levels and reduced reactive oxygen species formation in AGE-stimulated HUVECs in a concentration-dependent manner (P<0.05). We also showed that nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase 1 (HO-1) and nuclear factor kappa B (NF-κB) signaling was critical for the salidroside-mediated beneficial regulation. CONCLUSIONS Our results demonstrate that salidroside protects against AGE-induced endothelial dysfunction, and its effects may be in part attributed to the induction of HO-1 and attenuation of phosphorylated NF-κB p65.

Fasudil improves short-term echocardiographic parameters of diastolic function in patients with type 2 diabetes with preserved left ventricular ejection fraction: a pilot study

Left ventricular (LV) diastolic dysfunction is observed frequently in patients with type 2 diabetes; however, few studies have focused on the effect of the Rho-associated kinase inhibitor fasudil on cardiac performance in humans. We conducted a prospective pilot study to assess the impact of fasudil on LV diastolic function in patients with diabetes without systolic dysfunction. Two hundred and fifty eligible patients with type 2 diabetes (149 men [61.3 %] and 94 women [38.7 %]) with a mean age of 57.2 years were randomly assigned to fasudil (n = 122, 30 mg intravenously twice a day for 14 days) or placebo (n = 121) groups. Echocardiographic variables were measured at the baseline and 1 month after the intervention. Compared with the placebo group, the fasudil group showed a significant decrease in diastolic blood pressure and in the peak of late diastolic transmitral flow (Am) (P < 0.05 for both). Deceleration time (DT), isovolumic relaxation time (IVRT), the peak of early diastolic annular velocity (e'), the peak of late diastolic annular velocity, and E/e' also exhibited a significant improvement (all, P < 0.05) after fasudil administration. Furthermore, the Em/Am ratio and IVRT, DT, and E/e' values recorded after fasudil treatment in the subgroup with impaired LV relaxation significantly differed from the corresponding values in the subgroup with normal LV relaxation (all, P < 0.05). Fasudil improves short-term echocardiographic parameters of LV diastolic function in patients with type 2 diabetes with preserved left ventricular ejection fraction.

Prognostic significance of fragmented QRS in patients with non-ST elevation myocardial infarction: results of a 1-year, single-center follow-up

OBJECTIVES

The aim of this study was to evaluate the predictive value of fragmented QRS (fQRS) among non-ST elevation acute coronary syndrome (ACS) patients.

DESIGN

The fQRS on standard 12-lead ECGs in 179 patients (63% males, mean age 60.9 ± 12.3 years) were analyzed. Cardiac events and cardiac mortality were regarded as two outcomes to determine whether fQRS was a clinical prognostic factor; its prognostic value was then assessed adjusting for other covariates.

RESULTS

Cardiac mortality (18 (17.0%) vs. 4 (5.5%)) and major cardiac event rate (46 (43.4%) vs. 22 (30.1%)) were higher in the fQRS group compared with the non-fQRS group during a mean follow-up of 12 months. A Kaplan-Meier survival analysis revealed significantly lower event-free survival for cardiac events (p = 0.030) and cardiac mortality (p = 0.020). Multivariate Cox regression analysis revealed that significant fQRS was an independent significant predictor for cardiac events and cardiac mortality.

CONCLUSION

These results indicate that the occurrence of fQRS in the ECG is a powerful predictor of decreased survival in NSTEMI. The prognostic importance of fQRS was incremental to clinical and conventional factors.

Two-Year Outcome From Combining Cryoballoon Ablation and Left Atrial Appendage Closure: CLACBAC Study

Objective: Catheter ablation combined with left atrial appendage closure (LAAC) has emerged as a promising strategy for atrial fibrillation (AF) patients at high risk for stroke or with contraindications for oral anticoagulants (OACs). But the evidence for the long-term safety and efficacy of a combined procedure using cryoballoon ablation (CBA) with LAAC is still insufficient. Methods: From October 2015 to December 2017, a total of 76 consecutive non-valvular, drug-refractory AF patients who underwent a combined procedure of CBA and LAAC are included. Peri- and post-procedural safety and efficacy were evaluated through scheduled follow-ups and transesophageal echocardiography (TEE). Results: A total of 74 patients (97.4%) underwent the combined procedure and achieved instant pulmonary vein isolation and satisfactory LAAC. With a mean follow-up time of 23.7 ± 11.0 months, the recurrence of atrial arrhythmia was recorded in 35 patients (48.0%). In addition, a survival analysis shows a non-significant higher recurrence in persistent AF (p = 0.48). The overall OAC withdrawal rate was 97.2%, and one patient (1.4%) had a lethal hemorrhagic stroke while on single antiplatelet therapy. For safety concerns, the overall mortality was 2.7%, which resulted from one case of myocardial infarction on OAC and one hemorrhagic stroke, as mentioned. No other major hemorrhagic events occurred. Among the 72 patients (94.7%) who underwent TEE, one patient (1.4%) had device-related thrombosis and one patient (1.4%) had prominent residual flow (over 3 mm). Both were prescribed long-term OACs without severe complications occurring. Conclusions: Combining CBA with LAAC in a single procedure achieved considerable long-term safety and efficacy, providing a promising strategy for AF management.

The basic social medical insurance is associated with clinical outcomes in the patients with ST-elevation myocardial infarction: a retrospective study from Shanghai, China

OBJECTIVE

Several social economic factors play important roles in treatments of ST-elevation myocardial infarction (STEMI) and finally influence the clinical outcomes. The basic social medical insurance (BSMI) is an important economic factor in China's medical system. However, the impact of BSMI on clinical outcomes in STEMI patients has not been explored yet. The aim of this study is to investigate whether BSMI is a predictor of clinical outcomes in the patients with STEMI in Shanghai, China.

MATERIAL AND METHODS

In this retrospective study, 681 STEMI patients from different areas in Shanghai were classified into four groups: new rural cooperative medical scheme (NCMS) group, urban resident basic medical insurance scheme (URBMI) group, urban employee basic medical insurance scheme (UEBMI) group and UNINSURED group, major adverse events (cardiac death, nonfatal reinfarction, clinically driven target lesion revascularization/target vessel revascularization, stroke, heart failure) were regarded as study endpoints to determine whether BSMI was a prognostic factor.

RESULTS

During a mean follow-up of 36 months, the incidence of major adverse events was significantly higher in NCMS patients (64; 38.8%) compared with the other groups: URBMI (47; 24.6%); UEBMI (28; 15.6%); UNISURED (40; 27.6%). Similarly, cardiac mortality was also higher in NCMS group (19; 11.5%). A Kaplan-Meier survival analysis revealed significantly lower event-free survival rate for major adverse events (p < 0.001) and cardiac mortality (p = 0.01) in NCMS group. Multivariate Cox regression analysis revealed that BSMI was an important prognostic factor in STEMI patients.

CONCLUSION

These results demonstrate that BSMI is closely associated with the major adverse events-free survival rate at 36-month follow-up in the STEMI patients under the current policies in Shanghai, China.

Taxifolin ameliorates abdominal aortic aneurysm by preventing inflammation and apoptosis and extracellular matrix degradation via inactivating TLR4/NF-κB axis

BACKGROUND

Abdominal aortic aneurysm (AAA) is a serious aortic disease with high mortality. Vascular smooth muscle cells (VSMCs) loss is a prominent feature of AAA. Taxifolin (TXL) is a natural antioxidant polyphenol and possesses therapeutic functions in numerous human diseases. This study aimed to investigate TXL's impact on VSMC phenotype in AAA.

METHODS

In vitro and in vivo of VSMC injury model was induced by angiotensin II (Ang II). The potential function of TXL on AAA was determined using Cell Counting Kit-8, flow cytometry, Western blot, quantitative reverse transcription-PCR, and enzyme-linked immunosorbent assay. Meanwhile, TXL mechanism on AAA was checked by a series of molecular experiments. Also, TXL function on AAA in vivo was further evaluated using hematoxylin-eosin staining, TUNEL assay, Picric acid-Sirius red staining and immunofluorescence assay in C57BL/6 mice.

RESULTS

TXL alleviated Ang II-induced VSMC injury mainly by enhancing VSMC proliferation and weakening cell apoptosis, alleviating VSMC inflammation, and reducing extracellular matrix (ECM) degradation of VSMCs. Furthermore, mechanistic studies corroborated that TXL reversed the high levels of Toll-like receptor 4 (TLR4) and p-p65/p65 induced by Ang II. Also, TXL facilitated VSMC proliferation and reduced cell apoptosis, repressed inflammation, and ECM degradation of VSMCs, while these effects were reversed by TLR4 overexpression. In vivo studies further confirmed that TXL owned the function of alleviating AAA, such as alleviating collagen fiber hyperplasia and inflammatory cell infiltration in AAA mice, and repressing inflammation and ECM degradation.

CONCLUSION

TXL protected VSMCs against Ang II-induced injury through activating TLR4/noncanonical nuclear factor-kappaB(NF-κB).

In Patients with Coronary Artery Disease and Type 2 Diabetes, SIRT1 Expression in Circulating Mononuclear Cells Is Associated with Levels of Inflammatory Cytokines but Not with Coronary Lesions

While SIRT1 is significantly associated with atherosclerosis and diabetic complications, its relevance to coronary lesions in patients with coronary artery disease and type 2 diabetes has not been specifically investigated. Thus, we assessed SIRT1 expression in peripheral blood mononuclear cells in these patients. We found that SIRT1 expression did not significantly correlate with syntax scores from coronary angiography (p > 0.05). Notably, plasma levels of the inflammatory cytokines tumor necrosis factor-α, monocyte chemoattractant protein-1, and high-sensitivity C-reactive protein were markedly higher in diabetic patients (p < 0.05). In addition, SIRT1 expression was negatively correlated with levels of these cytokines, as well as that of interleukin-6 (p < 0.05). In summary, the data indicate that SIRT1 expression in peripheral blood mononuclear cells is significantly correlated with inflammatory cytokines levels in patients with coronary artery disease and type 2 diabetes but not with the severity of coronary lesions.

Patients With Larger Left Atrial Appendage Orifice Presented Worse Prognosis Contributed by Acute Heart Failure After Left Atrial Appendage Closure

Background Left atrial appendage (LAA) closure (LAAC) could prevent stroke in patients with atrial fibrillation. However, LAAC may impair the compliance of the left atrium and result in poor prognosis. This study aimed to comparatively evaluate the prognosis of LAAC among patients with different sizes of LAA orifice. Methods and Results Three hundred two consecutive patients who underwent successful LAAC were included and divided into 4 groups based on LAA orifice size that was measured using transesophageal echocardiography. Clinical outcomes including thromboembolic events, major cardiocerebrovascular adverse events, and acute heart failure (AHF) were compared among 4 quartile groups and between propensity-score matched groups of large and small LAAs. Through follow-up of 39.6±8.4 months, survival of thromboembolic events was similar. Survival of major cardiocerebrovascular adverse events was significantly lower in the group with the largest LAA orifice (log-rank P<0.001), including a higher incidence of AHF with New York Heart Association class III to IV (21.4%, log-rank P=0.009). A large LAA orifice (by cutoff) could predict major cardiocerebrovascular adverse events (hazard ratio, 3.749 [95% CI, 2.074-6.779]) in most patients, except for subgroups of those aged <65 years, with paroxysmal atrial fibrillation, and/or with failed rhythm/rate control. Further compared with a propensity-score matched small-LAA group, the large-LAA orifice group still presented worse survival of AHF with New York Heart Association class III to IV (log-rank P=0.010). Conclusions Patients with a larger LAA orifice presented a worse prognosis after LAAC, including a higher incidence of AHF. A large LAA orifice could predict a post-LAAC AHF event in most patients, except for young patients, patients with paroxysmal atrial fibrillation, and/or with failed rhythm/rate control. Registration URL: clinicaltrials.gov; Unique identifier: NCT04185142.

Rs4968309 in Myosin Light Chain 4 (MYL4) Associated With Atrial Fibrillation Onset and Predicts Clinical Outcomes After Catheter Ablation in Atrial Fibrillation Patients Without Structural Heart Disease

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia with serious complications and a high rate of recurrence after catheter ablation. Recently, mutation ofMYL4was reported as responsible for familial atrial cardiomyopathy and AF. This study aimed to determine the association between polymorphism inMYL4with the onset and recurrence of AF.

METHODS AND RESULTS

A total of 7 single-nucleotide polymorphisms were selected by linkage disequilibrium and genotyped in 510 consecutive AF patients and 192 controls without structural heart disease. A total of 246 AF patients who underwent cryoballoon ablation had a 1-year scheduled follow-up study for AF recurrence. C allele and CC genotype of rs4968309 and A allele of rs1515751were associated with AF onset both before and after adjustment of covariation (age, sex, hypertension, and diabetes). AF type and left atrial size were different among the genotypes of rs4968309. Moreover, CC genotype of rs4968309 increased susceptibly of AF recurrence after cryoballoon ablation. The prevalence of hypertension was associated with rs1515752, and left atrial size was associated with the genotype of rs2071438.

CONCLUSIONS

C allele and CC genotype of rs4968309 inMYL4were associated with AF onset and recurrence. Moreover, the A allele of rs1515751 had a significant association with AF onset. The polymorphisms ofMYL4can predict AF onset and prognosis after ablation in AF patients without structural heart disease.

Elevated plasma S100A1 level is a risk factor for ST-segment elevation myocardial infarction and associated with post-infarction cardiac function

AIM

To investigate the association between plasma S100A1 level and ST-segment elevation myocardial infarction (STEMI) and potential significance of S100A1 in post-infarction cardiac function.

METHODS

We examined the plasma S100A1 level in 207 STEMI patients (STEMI group) and 217 clinically healthy subjects for routine physical examination without a history of coronary artery disease (Control group). Baseline characteristics and concentrations of relevant biomarkers were compared. The relationship between S100A1 and other plasma biomarkers was detected using correlation analysis. The predictive role of S100A1 on occurrence of STEMI was then assessed using multivariate ordinal regression model analysis after adjusting for other covariates.

RESULTS

The plasma S100A1 level was found to be significantly higher (P<0.001) in STEMI group (3197.7±1576.0 pg/mL) than in Control (1423.5±1315.5 pg/mL) group. Furthermore, the correlation analysis demonstrated plasma S100A1 level was significantly associated correlated with hypersensitive cardiac troponin T (hs-cTnT) (r = 0.32; P < 0.001), creatine kinase MB (CK-MB) (r = 0.42, P < 0.001), left ventricular eject fraction (LVEF) (r = -0.12, P = 0.01), N-terminal prohormone of brain natriuretic peptide (NT-proBNP) (r = 0.61; P < 0.001) and hypersensitive C reactive protein (hs-CRP) (r = 0.38; P < 0.001). Moreover, the enrolled subjects who with a S100A1 concentration ≤ 1965.9 pg/mL presented significantly better cardiac function than the rest population. Multivariate Logistic regression analysis revealed that S100A1 was an independent predictor for STEMI patients (OR: 0.671, 95% CI 0.500-0.891, P<0.001). In addition, higher S100A1 concentration (> 1965.9 pg/mL) significantly increased the risk of STEMI as compared with the lower level (OR: 6.925; 95% CI: 4.15-11.375; P<0.001).

CONCLUSION

These results indicated that the elevated plasma S100A1 level is an important predictor of STEMI in combination with several biomarkers and also potentially reflects the cardiac function following the acute coronary ischemia.

Circulating Matrix Metalloproteinase-28 Levels Are Related to GRACE Scores and Short-Term Outcomes in Patients with Acute Myocardial Infarction

OBJECTIVE

To investigate the relationship between the level of matrix metalloproteinase-28 (MMP-28) in patients with acute myocardial infarction (AMI) and the global registry of acute coronary events (GRACE) scores as well as their short-term prognosis.

METHODS

Two hundred eleven patients with AMI were enrolled, and their basic clinical characteristics were collected for determining the GRACE score. We measured the plasma levels of MMP-28 and other biomarkers in the study population. The association of MMP-28 levels with cardiac events and cardiac deaths occurring within 30 days of discharge was evaluated with multivariable Cox proportional hazard models.

RESULTS

The MMP-28 levels were significantly higher in patients with acute ST-elevation myocardial infarction (STEMI) than in patients with non-ST-elevation myocardial infarction (NSTEMI) (P < 0.01). Correlation analysis showed that the level of MMP-28 was positively correlated with the GRACE score in patients with AMI (R 2 = 0.366, P < 0.05). Cox multivariate regression results showed that MMP-28 was associated with cardiovascular events during the hospitalization and 30 days after discharge (P < 0.01). In addition, Kaplan-Meier analysis showed that cardiac events and deaths were significantly higher in patients with MMP-28 ≥ 1.21 ng/mL (all P < 0.01).

CONCLUSION

There is a correlation between the plasma MMP-28 level and GRACE score in patients with AMI. MMP-28 is also associated with cardiovascular events and cardiovascular deaths during the hospitalization of patients and within 30 days of discharge.

Impact of Stable Coronary Artery Disease on the Efficacy of Cryoballoon Ablation for the Atrial Fibrillation

BACKGROUND

Cryoballoon ablation has become an effective strategy for the treatment of atrial fibrillation (AF) without coronary artery disease (CAD). AF is usually coupled with CAD. However, the impact of CAD on the outcome of cryoablation in AF patients remains unclear. The objective of our study was to investigate the impact of stable CAD on the efficacy of cryoballoon ablation for AF.

MATERIALS AND METHODS

The data of 384 patients who underwent AF cryoablation were consecutively collected. Patients were classified into a CAD group and a non-CAD group. All patients were listed for a scheduled follow-up visit in the outpatient clinics to evaluate the AF recurrence at 1, 3, 6 and 12 months after cryoablation.

RESULTS

Seventy-four patients (19.3%) suffered from stable CAD, and 31 (8.1%) of them underwent PCI before cryoablation. Cryoablation was performed in 1521 pulmonary veins and 99.1% of pulmonary vein isolation was achieved. Successful follow-up was obtained in 354 patients after a mean of 12 ± 6 months, in which 280 patients (79.1%) had maintained stable sinus rhythm, and 74 patients (20.9%) had AF recurrence. There was no significant difference in AF recurrence between patients with and without CAD (16.4% versus 22.0%). Furthermore, the presence, location and severity of CAD were not associated with AF recurrence after cryoablation while persistent AF, N-terminal pro-brain natriuretic peptide and left atrial diameter served as independent predictors of AF recurrence.

CONCLUSIONS

Cryoballoon ablation is effective for the treatment of AF in stable CAD patients. The presence of CAD has no impact on the AF recurrence after cryoablation.

Acute left atrial ridge lesion after cryoballoon ablation: How does this affect left atrial appendage closure combined procedure?

BACKGROUND

Acute left atrial ridge (LAR) lesions have been observed following atrial fibrillation (AF) ablation. However, LAR lesions had not yet been quantitatively evaluated and their influence on procedure combining cryoballoon (CB) ablation with left atrial appendage closure (LAAC) remained to be explored.

METHODS

The profile of LAR lesions was measured by transesophageal echocardiography (TEE) in 117 consecutive nonvalvular AF patients, who underwent the combined procedure of CB ablation and LAAC. We thoroughly investigated how LAR lesions correlated with baseline variables and clinical outcomes.

RESULTS

A total of 95 out of 96 available TEE images presented prominent acute LAR lesions. In terms of dimensions, there was a greater change in width (Δwidth = 3.6 ± 2.3 mm) than the thickness (Δthickness = 2.6 ± 3.5 mm), and the outer ostium was narrowed (Δouter ostium diameter = -3.4 ± 4.0 mm), while the inner ostium remained unchanged. A higher nadir temperature when freezing the left superior pulmonary vein (LSPV) led to an LAR lesion with a two times greater width (adjusted odds ratio = 1.16; 95% confidence interval, 1.02-1.31). In the evaluation of LAAC outcomes, four patients implanted with Watchman devices had minimal residual flow at the inferior border, while two implanted with LAmbre devices developed residual flow at the LAR side. Clinical outcomes were similar between groups divided by lesion size.

CONCLUSION

Acute LAR lesions frequently occurred following the CB ablation combined procedure, and lesion width positively correlates with LSPV nadir temperature. The presence of these lesions affects the measurement of pacifier devices but has little impact on that of occluder devices.

Association between serum S100A1 level and Global Registry of Acute Coronary Events score in patients with non-ST-segment elevation acute coronary syndrome

Objective Acute coronary syndrome (ACS) is associated with several clinical syndromes, one of which is acute non-ST-segment ACS (NSTE-ACS). S100A1 is a calcium-dependent regulator of heart contraction and relaxation. We investigated the association between the serum S100A1 level and the Global Registry of Acute Coronary Events (GRACE) risk score in patients with NSTE-ACS and the potential of using the serum S100A1 level to predict the 30-day prognosis of NSTE-ACS. Methods The clinical characteristics of 162 patients with NSTE-ACS were analyzed to determine the GRACE score. The serum S100A1 concentration was determined using fasting antecubital venous blood. The patients were divided into different groups according to the serum S100A1 level, and the 30-day NSTE-ACS prognosis was evaluated using Kaplan-Meier analysis. Results The serum S100A1 levels differed significantly among the groups. Correlation analysis showed that the serum S100A1 level was positively correlated with the GRACE score. Kaplan-Meier analysis revealed that the number of 30-day cardiac events was significantly higher in patients with an S100A1 level of >3.41 ng/mL. Conclusions S100A1 is a potential biomarker that can predict the progression of NSTE-ACS and aid in its early risk stratification and prognosis.