Advanced glycation end product-modified low-density lipoprotein promotes pro-osteogenic reprogramming via RAGE/NF-κB pathway and exaggerates aortic valve calcification in hamsters.

BACKGROUND: Advanced glycation end product-modified low-density lipoprotein (AGE-LDL) is related to inflammation and the development of atherosclerosis. Additionally, it has been demonstrated that receptor for advanced glycation end products (RAGE) has a role in the condition known as calcific aortic valve disease (CAVD). Here, we hypothesized that the AGE-LDL/RAGE axis could also be involved in the pathophysiological mechanism of CAVD. METHODS: Human aortic valve interstitial cells (HAVICs) were stimulated with AGE-LDL following pre-treatment with or without interleukin 37 (IL-37). Low-density lipoprotein receptor deletion (Ldlr-/-) hamsters were randomly allocated to chow diet (CD) group and high carbohydrate and high fat diet (HCHFD) group. RESULTS: AGE-LDL levels were significantly elevated in patients with CAVD and in a hamster model of aortic valve calcification. Our in vitro data further demonstrated that AGE-LDL augmented the expression of intercellular cell adhesion molecule-1 (ICAM-1), interleukin-6 (IL-6) and alkaline phosphatase (ALP) in a dose-dependent manner through NF-κB activation, which was attenuated by nuclear factor kappa-B (NF-κB) inhibitor Bay11-7082. The expression of RAGE was augmented in calcified aortic valves, and knockdown of RAGE in HAVICs attenuated the AGE-LDL-induced inflammatory and osteogenic responses as well as NF-κB activation. IL-37 suppressed inflammatory and osteogenic responses and NF-κB activation in HAVICs. The vivo experiment also demonstrate that supplementation with IL-37 inhibited valvular inflammatory response and thereby suppressed valvular osteogenic activities. CONCLUSIONS: AGE-LDL promoted inflammatory responses and osteogenic differentiation through RAGE/NF-κB pathway in vitro and aortic valve lesions in vivo. IL-37 suppressed the AGE-LDL-induced inflammatory and osteogenic responses in vitro and attenuated aortic valve lesions in a hamster model of CAVD.

Sphingolipids: drivers of cardiac fibrosis and atrial fibrillation.

Sphingolipids (SLs) are vital constituents of the plasma membrane of animal cells and concurrently regulate numerous cellular processes. An escalating number of research have evinced that SLs assume a crucial part in the progression of tissue fibrosis, a condition for which no efficacious cure exists as of now. Cardiac fibrosis, and in particular, atrial fibrosis, is a key factor in the emergence of atrial fibrillation (AF). AF has become one of the most widespread cardiac arrhythmias globally, with its incidence continuing to mount, thereby propelling it to the status of a major public health concern. This review expounds on the structure and biosynthesis pathways of several pivotal SLs, the pathophysiological mechanisms of AF, and the function of SLs in cardiac fibrosis. Delving into the influence of sphingolipid levels in the alleviation of cardiac fibrosis offers innovative therapeutic strategies to address cardiac fibrosis and AF.

Transesophageal echocardiography-guided percutaneous closure of the patent foramen ovale only uses the sheath.

Background: Percutaneous closure of the patent foramen ovale (PFO) is primarily guided by fluoroscopy in the catheter room, during which procedure both the guidewire and sheath need to pass through the PFO. We performed PFO closure using a transesophageal echocardiography (TEE)-guided approach and only the sheath was passed through the PFO during the procedure. This study aimed to evaluate the feasibility and safety of PFO closure using this technique. Methods: A retrospective observational study was performed. A total of 117 consecutive adult patients underwent percutaneous PFO closure without fluoroscopy, under the sole guidance of TEE in our hospital between December 2018 and December 2021. The data of each patient consisted of preoperative, operative, and postoperative variables collected. The primary outcome is that the occluder was successfully released. The secondary outcomes included perioperative and follow-up transthoracic echocardiography (TTE), Headache impact test-6 (HIT-6) score and clinical symptoms. Results: Transvenous PFO closure under TEE guidance was successful in all cases. The sample consisted of 93 females and 24 males with an average age of 42.3±7.8 years. There were 28 patients with preoperative cerebral infarction [Risk of Paradoxical Embolism (RoPE) score >6 points] and 89 patients with migraine. All patients underwent a preoperative TEE to confirm the presence of PFO, and contrast-enhanced transcranial Doppler (c-TCD) acoustic contrast suggested grades 3 to 4. The average time of surgery for patients (puncture to removal of the sheath) was 32 minutes. Three cases of vagus nerve reflex manifestations during surgery and two cases of transient ventricular arrhythmia all improved after symptomatic treatment. There were no instances of metal allergy, hemolysis, or other acute vascular procedural complications. For all 89 patients with migraine, significant relief or resolution was achieved during the first six-month follow-up (P<0.001). Conclusions: As a monotherapy, percutaneous closure of PFO guided by TEE where only the sheath passes through the PFO during the operation is an effective procedure with a high success rate and a low complication rate.

Synergetic EGCG and coenzyme Q10 DSPC liposome nanoparticles protect against myocardial infarction.

At the site of myocardial infarction (MI), various phenomena such as oxidative stress and myocardial apoptosis can be observed. Both epigallocatechin gallate (EGCG) and coenzyme Q10 (CoQ10) exhibit antioxidant and anti-inflammatory effects. Macrophages have demonstrated a higher internalization rate of cationic liposomes, thereby increasing their bioavailability. This study utilized EGCG in synergy with CoQ10 as an antioxidant agent and distearyl phosphatidylcholine (DSPC) as the carrier, to create liposome nanoparticles known as CE-LNPs. The CE-LNPs exhibited favorable biocompatibility and were effectively engulfed by macrophages in vitro. In addition, the CE-LNPs effectively eradicated reactive oxygen species (ROS) in hypoxic cardiomyocytes, mitigated myocardial cell apoptosis, and sustained the functionality and proliferation of myocardial cells. The anti-apoptotic effect of the CE-LNPs was further validated through TUNEL and Annexin V FITC/PI experiments. The therapeutic efficacy of CE-LNPs was evaluated in a murine model of MI. CE-LNPs demonstrated a significant reduction in scar area in vivo, facilitating cardiac repair and improving cardiac function. These findings provide evidence that EGCG synergistically combined with CoQ10 in DSPC liposome nanoparticles offers protection against MI.

Phosphatidylethanolamine aggravates Angiotensin II-induced atrial fibrosis by triggering ferroptosis in mice.

As atrial fibrosis is the main feature of atrial structural remodeling, inhibiting atrial fibrosis is crucial to the prevention of atrial fibrillation (AF) progression. Research has shown the correlation between abnormal lipid metabolism and AF progression. However, the effect of specific lipids on atrial fibrosis remains unclear. In the present study, we applied ultra-high-performance lipidomics to analyze the lipid profiles in patients with AF and identify phosphatidylethanolamine (PE) as the differential lipid associated with AF. To detect the effect of the differential lipid on atrial fibrosis, we performed the intraperitoneal injection of Angiotensin II (Ang II) to mice to induce atrial fibrosis and supplemented PE in diets. We also treated atrial cells with PE to evaluate the cellular effect of PE. We found that PE supplementation aggravated atrial fibrosis and increased the expression of the fibrosis-related protein in vitro and in vivo. Moreover, we detected the effect of PE on the atrium. We found that PE increased oxidation products and regulated the expression of ferroptosis-related proteins, which could be alleviated by a ferroptosis inhibitor. PE increased peroxidation and mitochondrial damage in vitro, which promoted cardiomyocyte death induced by Ang II. Examination of protein expression in cardiomyocytes indicated that PE triggered ferroptosis and caused cell death to participate in myocardium fibrosis. In summary, our findings demonstrated the differential lipid profiles of AF patients and revealed the potential effect of PE on atrial remodelling, suggesting that inhibition of PE and ferroptosis might serve as a potential therapy to prevent AF progression.

Anti-Oxidative, Anti-Apoptotic, and M2 Polarized DSPC Liposome Nanoparticles for Selective Treatment of Atherosclerosis.

Purpose: Oxidative stress is one of the main pathogenic factors of atherosclerosis. However, no antioxidants have brought positive effects on the treatment of atherosclerosis. To selectively treat atherosclerosis, various means such as antioxidation, anti-apoptosis, and M2 polarization are used. The ultimate goal is that multiple regulatory pathways can help to treat atherosclerosis. Patients and Methods: In this study, Simvastatin (SIM) as a model drug, EGCG as an antioxidant agent, and distearyl phosphatidylcholine (DSPC) as major carriers were used to make liposome nanoparticles (SE-LNPs). The cytotoxicity, phagocytosis, antioxidant, and anti-apoptotic properties of nanoparticles were tested in vitro. ApoE-/- atherosclerotic mice were treated with nanoparticles. The changes of aortic Oil red staining, blood lipid, HE, and Masson sections of the aortic root were observed. Results: SE-LNPs exhibited a sustained release profile, potentially enabling the accumulation of the majority amount of drugs at the atherosclerotic plaque. The phagocytosis effect was stronger in RAW. The anti-oxidative and anti-apoptotic effects of the formulation were verified in vitro. SE-LNPs promoted the polarization of M2 macrophages. The therapeutic effect of SE-LNPs was assessed in the ApoE-/- mice model of atherosclerosis. SE-LNPs reduced reactive oxygen species and lipids in vivo. The results of Oil red staining, blood lipid, HE, and Masson sections of the aortic root showed the recovery of the focus. Conclusion: Studies have shown that SE-LNPs could resist oxidation, and apoptosis, promote M2 polarization, and reduce blood lipids and lesions, which is a reliable and selective treatment for atherosclerosis.

Postoperative central venous pressure is associated with acute kidney injury in patients undergoing coronary artery bypass grafting.

Objective: The present study aimed to investigate the association of postoperative central venous pressure (CVP) with acute kidney injury (AKI) and mortality in patients undergoing coronary artery bypass grafting (CABG). Method: Patients who underwent CABG in the MIMIC-III database were included and divided into two groups according to the optimal cutoff value of CVP for postoperative AKI determined by the receiver operating characteristic (ROC) curves. The association of CVP with AKI and mortality was determined by multivariate regression models. A 1:1 propensity score matching (PSM) was performed to balance the influence of potential confounding factors. Results: A total of 3,564 patients were included and divided into High CVP group (CVP ≥ 10.9 mmHg) and Low CVP group (CVP < 10.9 mmHg) according to the ROC analysis. Patients in High CVP group presented with higher AKI incidence (420 (28.2%) vs. 349 (16.8), p < 0.001), in-hospital mortality (28 (1.9%) vs. 6 (0.3%), p < 0.001) and 4-year mortality (149 (15.8%) vs. 162 (11.1%), p = 0.001). Multivariate regression model showed that CVP was an independent risk factor for the postoperative AKI (OR: 1.071 (1.035, 1.109), p < 0.001), in-hospital mortality (OR: 1.187 (1.026, 1.373), p = 0.021) and 4-year mortality (HR: 1.049 (1.003, 1.096), p = 0.035). A CVP above 10.9 mmHg was significantly associated with about 50% higher risk of AKI (OR: 1.499 (1.231, 1.824), p < 0.001). After PSM, 1004 pairs of score-matched patients were generated. The multivariate logistic model showed that patients with CVP ≥ 10.9 mmHg had a significantly higher risk of AKI (OR: 1.600 (1.268, 2.018), p < 0.001) in the PSM subset. However, CVP, as a continuous or a dichotomic variable, was not independently associated with in-hospital mortality (OR: 1.202 (0.882, 1.637), p = 0.244; OR: 2.636 (0.399, 17.410), p = 0.314) and 4-year mortality (HR: 1.030 (0.974, 1.090), p = 0.297; HR: 1.262 (0.911, 1.749), p = 0.162) in the PSM dataset. Conclusion: A mean CVP ≥ 10.9 mmHg within the first 24 h after CABG was independently associated with a higher risk of postoperative AKI.

Normothermic Ex Vivo Heart Perfusion with Mesenchymal Stem Cell-Derived Conditioned Medium Improves Myocardial Tissue Protection in Rat Donation after Circulatory Death Hearts.

Objective: Adopting hearts from donation after circulatory death (DCD) is a promising approach to enlarge the donor pool. Nevertheless, DCD hearts experience severe warm ischemia/reperfusion (I/R) injury. Recent studies have demonstrated that conditioned medium (CM) derived from bone marrow mesenchymal stem cells (BMSCs) has the potential of reducing organ I/R injury. Therefore, we investigated whether DCD heart preservation with normothermic ex vivo heart perfusion (EVHP) and BMSCs-CM treatment could alleviate myocardial warm I/R injury in the DCD hearts. Methods: We randomly divided donor rats into two groups: (1) DCD-Control group and (2) DCD-CM group. Before DCD heart preservation with the normothermic EVHP system for 105 minutes, rats suffered from a 25-minute warm ischemia injury in the DCD procedure. Vehicle or CM (300 µl) was added to the perfusate at the beginning of the perfusion process. The cardiac function of DCD hearts in the DCD-Control and DCD-CM groups was measured every 30 minutes. Besides, non-DCD hearts were harvested from the beating-heart rats. Results: The antibody array demonstrated that the CM contained 14 bioactive factors involved in apoptosis, inflammation, and oxidative stress. Warm ischemia injury resulted in a significant increase in the level of oxidative stress, inflammation, and apoptosis in the DCD hearts of DCD-Control group. Furthermore, compared with the DCD-Control group, CM treatment increased the developed pressure, dP/dtmax and dP/dtmin of the left ventricular in the DCD hearts during a 90-minute EVHP. Moreover, the administration of CM attenuated the level of oxidative stress, inflammation, and apoptosis in the DCD hearts of the DCD-CM group. Conclusions: Normothermic EVHP combined with CM treatment can alleviate warm I/R injury in the DCD hearts by decreasing the level of oxidative stress, inflammatory response, and apoptosis, which might alleviate the shortage of donor hearts by adopting DCD hearts.

4-Octyl itaconate suppresses the osteogenic response in aortic valvular interstitial cells via the Nrf2 pathway and alleviates aortic stenosis in mice with direct wire injury.

Calcific aortic valve disease (CAVD) is the most prevalent valvular heart disease in older individuals, but there is a lack of drug treatment. The cellular biological mechanisms of CAVD are still unclear. Oxidative stress and endoplasmic reticulum stress (ER stress) have been suggested to be involved in the progression of CAVD. Many studies have demonstrated that 4-octyl itaconate (OI) plays beneficial roles in limiting inflammation and oxidative injury. However, the potential role of OI in CAVD has not been thoroughly explored. Thus, we investigated OI-mediated modulation of ROS generation and endoplasmic reticulum stress to inhibit osteogenic differentiation in aortic valve interstitial cells (VICs). In our study, calcified aortic valves showed increased levels of ER stress and superoxide anion, as well as abnormal expression of Hmox1 and NQO1. In VICs, OI activated the Nrf2 signaling cascade and contributed to Nrf2 stabilization and nuclear translocation, thus augmenting the expression of genes downstream of Nrf2 (Hmox1 and NQO1). Moreover, OI ameliorated osteogenic medium (OM)-induced ROS production, mitochondrial ROS levels and the loss of mitochondrial membrane potential in VICs. Furthermore, OI attenuated the OM-induced upregulation of ER stress markers, osteogenic markers and calcium deposition, which were blocked by the Nrf2-specific inhibitor ML385. Interestingly, we found that OM-induced ER stress and osteogenic differentiation were ROS-dependent and that Hmox1 silencing triggered ROS production, ER stress and elevated osteogenic activity, which were inhibited by NAC. Overexpression of NQO1 mediated by adenovirus vectors significantly suppressed OM-induced ER stress and osteogenic markers. Collectively, these results showed the anti-osteogenic effects of OI on AVICs by regulating the generation of ROS and ER stress by activating the Nrf2 signaling pathway. Furthermore, OI alleviated aortic stenosis in a mouse model with direct wire injury. Due to its antioxidant properties, OI could be a potential drug for the prevention and/or treatment of CAVD.

MicroRNA-205-5p plays a suppressive role in the high-fat diet-induced atrial fibrosis through regulation of the EHMT2/IGFBP3 axis.

OBJECTIVE: MicroRNAs (miRNAs) targeting has been revealed to be an appealing strategy for the treatment and management of atrial fibrillation (AF). In this research, we aimed to explore the mechanisms of miR-205-5p in reducing the high-fat diet (HFD)-induced atrial fibrosis through the EHMT2/IGFBP3 axis. METHODS: Expression levels of miR-205-5p, IGFBP3 and EHMT2 were determined in AF patients, cell fibrosis models and mouse atrial fibrosis models. Luciferase activity and RIP assays were performed to detect the binding between miR-205-5p and EHMT2, and ChIP assays were implemented to detect the enrichment of H3K9me2 and H3K4me3 in the promoter region of IGFBP3 in cells. The related experiments focusing on the inflammatory response, atrial fibrosis, mitochondrial damage, and metabolic abnormalities were performed to figure out the roles of miR-205-5p, IGFBP3, and EHMT2 in cell and mouse atrial fibrosis models. RESULTS: Low expression levels of miR-205-5p and IGFBP3 and a high expression of EHMT2 were found in AF patients, cell fibrosis models and mouse atrial fibrosis models. Upregulation of miR-205-5p reduced the expression of TGF-ß1, α-SMA, Col III and other fibrosis-related proteins. miR-205-5p overexpression targeted EHMT2 to regulate the methylation of H3 histones to promote IGFBP3 expression, which in turn affected the fibrosis of atrial muscle cells. In HFD-induced atrial fibrosis mice, upregulated miR-205-5p or elevated IGFBP3 alleviated atrial fibrosis, mitochondrial damage, and metabolic abnormalities. CONCLUSION: This study suggests that miR-205-5p attenuates HFD-induced atrial fibrosis via modulating the EHMT2/IGFBP3 axis. miR-205-5p alleviates high-fat diet-induced atrial fibrosis in mice via EHMT2/IGFBP3.

Preoperative albumin corrected anion gap is associated with in-hospital and long-term mortality in patients undergoing coronary artery bypass grafting in a retrospective cohort study.

Background: Coronary artery disease remains a global health concern and the leading cause of death. Till today, coronary artery bypass grafting (CABG) is one of the main treatment strategies for coronary artery disease, especially for Multivessel coronary disease or complex coronary lesions. The present study aimed to explore the relationship of preoperative albumin corrected anion gap (ACAG) with mortality in all those patients who undergoing CABG. Methods: All the patients undergoing CABG were included in the study. All clinical data were collected from CareVue and MetaVision system. The predictive value of ACAG for mortality was determined by receiver operating characteristic (ROC) curves survival curves were estimated using the Kaplan-Meier method. Multivariate regression models were constructed to determine the association of ACAG with mortality. Results: A total of 2,180 patients were identified and divided into a high ACAG group (ACAG ≥16.0 mmol/L) and low ACAG group (ACAG <16.0 mmol/L) according to the ROC analysis. Patients in the high ACAG group were older and presented with more comorbidities and concomitant valvular surgeries. Further more, in the high ACAG group, we observed a higher length of stay in the intensive care unit [3.88 (2.15, 7.09) vs. 2.29 (1.29, 3.94), P<0.001]. Both the in-hospital mortality [28 (4.5%) vs. 11 (0.7%), P<0.001], and the 4-year mortality [125 (27.1%) vs. 111 (12.7%), P<0.001] were also rised in those patients. And it was also showed in the survival curves, patients with ACAG ≥16.0 mmol/L had a significant lower 4-year survival (P<0.001). While in the multivariate regression model, we found ACAG was act as an independent risk factor for both the in-hospital mortality [odds ratio (OR): 1.248 (1.060, 1.470), P=0.008] and the 4-year mortality [hazard ratio (HR): 1.134 (1.063, 1.210), P<0.001]. An ACAG ≥16.0 mmol/L was significantly associated with a 2.7-fold risk of in-hospital mortality [OR: 2.732 (1.129, 6.610), P=0.026]. Conclusions: Preoperative ACAG is an independent risk factor for in-hospital and long-term mortality in CABG patients. A higher ACAG may relate to severe coronary artery stenosis and cardiac dysfunction, which is more likely to lead to a postoperative systemic inflammatory response, microcirculation disorder, and subsequent complications.

Targeting Ferroptosis to Treat Cardiovascular Diseases: A New Continent to Be Explored.

Cardiovascular diseases, including cardiomyopathy, myocardial infarction, myocardial ischemia/reperfusion injury, heart failure, vascular injury, stroke, and arrhythmia, are correlated with cardiac and vascular cell death. Ferroptosis is a novel form of non-apoptotic regulated cell death which is characterized by an iron-driven accumulation of lethal lipid hydroperoxides. The initiation and execution of ferroptosis are under the control of several mechanisms, including iron metabolism, glutamine metabolism, and lipid peroxidation. Recently, emerging evidence has demonstrated that ferroptosis can play an essential role in the development of various cardiovascular diseases. Recent researches have shown the ferroptosis inhibitors, iron chelators, genetic manipulations, and antioxidants can alleviate myocardial injury by blocking ferroptosis pathway. In this review, we systematically described the mechanisms of ferroptosis and discussed the role of ferroptosis as a novel therapeutic strategy in the treatment of cardiovascular diseases.

Profiling of miR-205/P4HA3 Following Angiotensin II-Induced Atrial Fibrosis: Implications for Atrial Fibrillation.

Objective: Atrial fibroblasts are the main component of atrial fibrosis. Data in previous studies proved the implication of miRNAs in AF progression and the association of miR-205 with cancer associated-fibroblasts, while no evidence supported the implication of miR-205 in atrial fibrosis. Therefore, this study aims to explore the effect and mechanism of miR-205/P4HA3 axis on atrial fibrosis. Methods: Angiotensin II (Ang II) was used to induce atrial fibrosis model in rats, which was verified by H&E staining and Masson staining. qRT-PCR and Western blot were applied to measure the expressions of miR-205, P4HA3, collagen I, and α-SMA. The rat atrial fibroblasts were isolated and then subjected to Ang II treatment or cell transfection for determination of cell biological functions using CCK-8, BrdU assay, TUNEL staining, and cell scratch assay. qRT-PCR and Western blot was applied to analyze the expressions of miR-205, P4HA3, collagen I, α-SMA, JNK, and p-JNK in atrial fibroblasts. Dual-luciferase reporter gene assay and RNA immune-precipitation experiment was employed to verify the binding relationship between miR-205 and P4HA3. Results: Ang II induced rats had disordered arrangement of atrial muscles with uneven nuclear sizes and necrotic atrial myocytes, and increased collagen deposition, in which elevated expressions of P4HA3, collagen I, and α-SMA as well as suppressed expression level of miR-205 were found. In vitro, Ang II treatment in atrial fibroblasts with overexpression of P4HA3 facilitated cellular migration and proliferation, with the induction of JNK signaling pathway. However, these trends were reversed after transfection with miR-205 mimic. P4HA3 is a target gene of miR-205. Conclusion: The miR-205/P4HA3 axis is implicated in atrial fibrosis by inhibition of rat fibroblast proliferation and migration and the inactivation of JNK signaling pathway.

Alterations of long non-coding RNA and mRNA profiles associated with extracellular matrix homeostasis and vascular aging in rats.

Vascular aging has been closely associated with various cardiovascular disorders; however, its molecular mechanism remains poorly understood. In our study, RNA sequencing was utilized to explore the expression profiles of long non-coding RNAs (lncRNAs) and mRNAs in the thoracic aortas of young (3 weeks) and old (16 weeks) rats. Functional categorization of differentially expressed mRNAs was evaluated using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases, and lncRNA-microRNA-mRNA networks was constructed using Cytoscape software. In addition, three upregulated and three downregulated lncRNAs were further confirmed by quantitative reverse transcriptase-polymerase chain reaction. A total of 36 lncRNAs and 922 mRNAs were differential expression in the thoracic aortas of young and older rats. In addition, we found differentially expressed mRNAs that were enriched in multiple biological processes and signaling pathways associated with angiogenesis, such as extracellular matrix-receptor interaction and adenosine 3',5'-monophosphate-activated protein kinase (AMPK) signaling. Moreover, AABR07013558.1, AABR07014823.1, and AABR07031489.1 were upregulated and ABR07053849.3, AABR07067310.2, and AC111292.1 were downregulated in the thoracic aortas of older rats compared with the young ones. Therefore, our findings provide several potential lncRNAs and mRNAs and signaling pathways related to vascular aging, which provide new clue for underlying the improvement of vascular aging.

The diagnostic accuracy of procalcitonin in infectious patients after cardiac surgery: a systematic review and meta-analysis.

Cardiac surgery with cardiopulmonary bypass (CPB) induces an acute inflammatory response that may lead to a systemic inflammatory response syndrome. The interest in procalcitonin (PCT) in the diagnosis of bacterial infection in patients after cardiac surgery remains less defined. The aim of this meta-analysis is to prospectively examine the discriminatory power of PCT as markers of infection in hospitalized patients with after cardiac surgery. The bivariate generalized nonlinear mixed-effect model and the hierarchical summary receiver operating characteristic model were used to estimate the pooled sensitivity, specificity and summary receiver operating characteristic curve. The pooled sensitivity and specificity were 0.81 (95% CI 0.75-0.87) and 0.78 (95% CI 0.73-0.83), respectively. The pooled positive likelihood ratio, and negative likelihood ratio of PCT were 3.74 (95% CI 2.98-4.69) and 0.24 (95% CI 0.17-0.32), respectively. The pooled area under the summary receiver operating characteristic curve of PCT using the HSROC method was 0.87 (95% CI 0.84- 0.90). This study indicated that PCT is a promising marker for the diagnosis of sepsis for those patients who undergo cardiac surgery.

ELAVL1 is transcriptionally activated by FOXC1 and promotes ferroptosis in myocardial ischemia/reperfusion injury by regulating autophagy.

AIMS: Myocardial ischemia is the most common form of cardiovascular disease and the leading cause of morbidity and mortality. Understanding the mechanisms is very crucial for the development of effective therapy. Therefore, this study aimed to investigate the functional roles and mechanisms by which ELAVL1 regulates myocardial ischemia and reperfusion (I/R) injury. METHODS: Mouse myocardial I/R model and cultured myocardial cells exposed to hypoxia/reperfusion (H/R) were used in this study. Features of ferroptosis were evidenced by LDH activity, GPx4 activity, cellular iron, ROS, LPO, and GSH levels. The expression levels of autophagy markers (Beclin-1, p62, LC3), ELAVL1 and FOXC1 were measured by qRT-PCR, immunostaining and western blot. RIP assay, biotin-pull down, ChIP and dual luciferase activity assay were employed to examine the interactions of ELAVL1/Beclin-1 mRNA and FOXC1/ELAVL1 promoter. CCK-8 assay was used to examine viability of cells. TTC staining was performed to assess the myocardial I/R injury. RESULTS: Myocardial I/R surgery induced ferroptosis and up-regulated ELAVL1 level. Knockdown of ELAVL1 decreased ferroptosis and ameliorated I/R injury. Si-ELAVL1 repressed autophagy and inhibition of autophagy by inhibitor suppressed ferroptosis and I/R injury in myocardial cells. Increase of autophagy could reverse the effects of ELAVL1 knockdown on ferroptosis and I/R injury. ELAVL1 directly bound with and stabilized Beclin-1 mRNA. Furthermore, FOXC1 bound to ELAVL1 promoter region and activated its transcription upon H/R exposure. CONCLUSION: FOXC1 transcriptionally activated ELAVL1 may promote ferroptosis during myocardial I/R by modulating autophagy, leading to myocardial injury. Inhibition of ELAVL1-mediated autophagic ferroptosis would be a new viewpoint in the treatment of myocardial I/R injury.

Donor heart preservation with hypoxic-conditioned medium-derived from bone marrow mesenchymal stem cells improves cardiac function in a heart transplantation model.

BACKGROUND: In heart transplantation, donor hearts inevitably suffer from ischemia/reperfusion (I/R) injury, which leads to primary graft dysfunction and affects patients' survival rate. Bone marrow mesenchymal stem cells (BMSCs) have been reported to attenuate myocardial I/R injury via their paracrine effects, which can be enhanced by hypoxic preconditioning. We hypothesized that the donor heart preservation with hypoxic conditioned medium (CdM) derived from BMSCs would improve post-transplant graft function. METHODS: Normoxic or hypoxic CdM were isolated from rat BMSCs cultured under normoxic (20% O2) or hypoxic (1% O2) condition. Donor hearts were explanted; stored in cardioplegic solution supplemented with either a medium (vehicle), normoxic CdM (N-CdM), or hypoxic CdM (H-CdM); and then heterotopically transplanted. Antibody arrays were performed to compare the differences between hypoxic and normoxic CdM. RESULTS: After heart transplantation, the donor heart preservation with normoxic CdM was associated with a shorter time to return of spontaneous contraction and left ventricular systolic diameter, lower histopathological scores, higher ejection fraction, and fractional shortening of the transplanted hearts. The cardioprotective effects may be associated with the inhibition of apoptosis and inflammation, as reflected by less TUNEL-positive cells and lower levels of plasma proinflammatory cytokines (interleukin-1ß, interleukin-6, tumor necrosis factor-α) and cardiac troponin I in the N-CdM group compared with the vehicle group. These therapeutic effects can be further enhanced by hypoxic preconditioning. Antibody arrays revealed that nine proteins were significantly increased in hypoxic CdM compared with normoxic CdM. Furthermore, compared with vehicle and N-CdM groups, the protein levels of PI3K and p-Akt/Akt ratio in the transplanted hearts significantly increased in the H-CdM group. However, no significant difference was found in the phosphorylation of Smad2 and Smad3 for the donor hearts among the three groups. CONCLUSIONS: Our results indicate that the cardioplegic solution-enriched with hypoxic CdM can be a novel and promising preservation solution for donor hearts.

Machine perfusion of donor heart with normothermic blood versus hypothermic HTK in preserving coronary endothelium in a porcine model of DCD.

BACKGROUND: Both machine perfusion (MP) of donor hearts with autologous blood and crystalloid perfusates have advantages and disadvantages. Currently, which of the aforementioned preservation strategies can better preserve the coronary endothelium has not yet been determined. We aim to compare the impact of hypothermic continuous MP with histidine-tryptophan-ketoglutarate (HTK) solution versus normothermic continuous MP with autologous blood on coronary endothelium in a porcine ex vivo model of donation following circulatory death (DCD). METHODS: DCD pigs underwent circulatory arrest via asphyxiation followed by 30-minute warm ischemia time. Donor hearts were preserved with either hypothermic MP with HTK solution (MP + HTK group; 4 ℃; n=6), or normothermic MP with blood (MP + blood group; 37 ℃; n=6) for 4 hours. After 2-hour ex vivo reperfusion, the assessment of endothelial-dependent (Edep) and -independent (Eind) relaxation of coronary artery, histopathological analysis, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay were performed. RESULTS: Preservation of DCD hearts with MP + Blood strategy significantly improved both Edep and Eind vasorelaxation of coronary artery compared with MP + HTK strategy (maximum relaxation to bradykinin: MP + HTK 80.9%±2.6% vs. MP + Blood 91.9%±1.9%, P<0.001; maximum relaxation to sodium nitroprusside: MP + HTK 97.1%±1.0% vs. MP + Blood 99.8%±0.2%, P<0.05). MP + Blood strategy significantly decreased nitrotyrosine but increased intercellular adhesion molecule-1 immunoreactivity in the coronary artery. The number of TUNEL-positive cells in MP + Blood group were significantly fewer compared with MP + HTK group. CONCLUSIONS: Compared with MP + HTK strategy, MP + Blood strategy significantly alleviates coronary endothelial dysfunction during donor heart preservation. This protective effect is associated with the inhibition of apoptosis and nitro-oxidative stress in coronary artery.

Lymphotoxin beta receptor is associated with regulation of microRNAs expression and nuclear factor-kappa B activation in lipopolysaccharides (LPS)-stimulated vascular smooth muscle cells.

BACKGROUND: The aim of present study is to investigate the role of lymphotoxin beta receptor (Ltßr) in lipopolysaccharides (LPS)-induced inflammation in vascular smooth muscle cells (VSMCs) and whether its effects are mediated by modulating microRNAs (miRNAs) and nuclear factor-kappa B (NF-κB). METHODS: Mouse aortic smooth muscle cell (SMC) line (MOVAS cells) were transduced with short hairpin Ltßr (shLtßr) and mRNA and protein expression level of Ltßr were measured by qPCR and Western blot in shLtßr-transduced cells. Lentiviral vector-transduced (control) and lentiviral vector/shLtßr-transduced MOVAS cells were stimulated with LPS (1 µg/mL) for 0, 16, or 24 h. Then the mRNA and protein levels of Ltßr, interleukin-18 (IL-18), p-p65, p65 and vascular cell adhesion molecule 1 (VCAM-1) were measured by real-time quantitative polymerase chain reaction (qPCR), Western blot and enzyme-linked immunosorbent assay (ELISA). Different miRNAs expression in LPS-stimulated normal and shLtßr-transduced cells were detected by small RNA sequencing (smRNA-seq). RESULTS: The mRNA and protein expression of Ltßr was significantly downregulated in shLtßr-transduced cells. LPS-increased the mRNA and protein levels of Ltßr, IL-18, p-p65 and VCAM-1 in were attenuated by shLtßr transducing compared with LPS-stimulated control group. Moreover, LPS treatment induced 10 upregulated and 64 downregulated miRNAs in shLtßr-transduced cells compared with control cells. Moreover, miR-146b-5p and miR-27a-5p levels were significantly decreased in shLtßr-transduced cells. CONCLUSIONS: Our results show for the first time that the role of Ltßr in regulating inflammatory response in LPS-stimulated VSMCs via modulating miRNAs and NF-κB pathway. Our findings might provide valuable information with respect to better understanding in the treatment of cardiovascular diseases, such as atherosclerosis.