Predictive Value of Serum microRNA-29b-3p in Recurrence of Atrial Fibrillation After Radiofrequency Catheter Ablation.

Objective: Atrial fibrillation (AF) is a common arrhythmia. This study explored serum miR-29b-3p expression in AF patients and its value in predicting AF recurrence after radiofrequency catheter ablation (RFCA). Methods: Totally 100 AF patients who underwent RFCA were enrolled, with 100 individuals without AF as controls. Serum miR-29b-3p expression in participants was determined using RT-qPCR. The correlation between miR-29b-3p and atrial fibrosis markers (FGF-21/FGF-23) was assessed by Pearson analysis. The diagnostic efficacy of serum miR-29b-3p and FGF-21/FGF-23 in predicting AF recurrence after RFCA was analyzed by the receiver operating characteristic (ROC) curves. The Kaplan-Meier method was adopted to evaluate the effect of miR-29b-3p expression on the incidence of AF recurrence after RFCA. The independent risk factors for AF recurrence after RFCA were analyzed by logistic regression analysis. Results: Serum miR-29b-3p was poorly expressed in AF patients. After RFCA, AF patients showed elevated serum miR-29b-3p expression. Serum miR-29b-3p expression in AF patients negatively correlated with serum FGF-21 and FGF-23 concentrations. The cut-off values of serum miR-29b-3p, FGF-21, and FGF-23 in identifying AF recurrence were 0.860 (sensitivity: 100.00%, specificity: 39.71%), 222.2 pg/mL (sensitivity: 96.88%, specificity: 32.35%) and 216.3 ng/mL (sensitivity: 53.13%, specificity: 70.59%), respectively. Patients with low miR-29b-3p expression had a significantly higher incidence of AF recurrence than patients with high miR-29b-3p expression. Serum miR-29b-3p expression was one of the independent risk factors for AF recurrence after RFCA. Conclusion: Low miR-29b-3p expression in AF patients has certain predictive values and is one of the independent risk factors for AF recurrence after RFCA.

The role of CREG1 in megakaryocyte maturation and thrombocytopoiesis.

Abnormal megakaryocyte maturation and platelet production lead to platelet-related diseases and impact the dynamic balance between hemostasis and bleeding. Cellular repressor of E1A-stimulated gene 1 (CREG1) is a glycoprotein that promotes tissue differentiation. However, its role in megakaryocytes remains unclear. In this study, we found that CREG1 protein is expressed in platelets and megakaryocytes and was decreased in the platelets of patients with thrombocytopenia. A cytosine arabinoside-induced thrombocytopenia mouse model was established, and the mRNA and protein expression levels of CREG1 were found to be reduced in megakaryocytes. We established megakaryocyte/platelet conditional knockout (Creg1pf4-cre) and transgenic mice (tg-Creg1). Compared to Creg1fl/fl mice, Creg1pf4-cre mice exhibited thrombocytopenia, which was mainly caused by inefficient bone marrow (BM) thrombocytopoiesis, but not by apoptosis of circulating platelets. Cultured Creg1pf4-cre-megakaryocytes exhibited impairment of the actin cytoskeleton, with less filamentous actin, significantly fewer proplatelets, and lower ploidy. CREG1 directly interacts with MEK1/2 and promotes MEK1/2 phosphorylation. Thus, our study uncovered the role of CREG1 in the regulation of megakaryocyte maturation and thrombopoiesis, and it provides a possible theoretical basis for the prevention and treatment of thrombocytopenia.

Efficiency of nicotinamide-based supportive therapy in lymphopenia for patients with ordinary or severe COVID-19: A randomized controlled trial.

BACKGROUND: This study aimed to investigate the efficiency of nicotinamide-based supportive therapy for lymphopenia in patients with coronavirus disease-2019 (COVID-19). METHODS: Twenty four patients diagnosed with COVID-19 were randomly divided into 2 groups (n = 12) during hospitalization in a ratio of 1:1. Based on conventional treatment, the treatment group was administered 100 mg nicotinamide 5 times a day for 2 days. The control group received routine treatment only. The primary endpoint was the change in the absolute lymphocyte count. The secondary endpoints included both in-hospital death and the composite endpoint of aggravation, according to upgraded oxygen therapy, improved nursing level, and ward rounds of superior physicians for changes in conditions. RESULTS: Full blood counts before and after nicotinamide administration were comparable in each group (all P > .05). Before and after receiving nicotinamide, mean absolute lymphocyte counts were similar between the two groups ([0.94 ± 0.26] × 109/L vs [0.89 ± 0.19] × 109/L, P = .565; [1.15 ± 0.48] × 109/L vs [1.02 ± 0.28] × 109/L, P = .445, respectively). Therefore, there was no statistically significant difference in the lymphocyte improvement rate between the two groups (23.08 ± 46.10 vs 16.52 ± 24.10, P = .67). There was also no statistically significant difference in the secondary endpoints between the two groups. CONCLUSION: Among patients with COVID-19, there was no statistically significant difference in the change of whole blood counts and absolute lymphocyte counts before and after intervention in both groups. Therefore, no new evidence has been found regarding the effect of niacinamide on lymphopenia in COVID-19 patients.

Neutrophil infiltration and myocarditis in patients with severe COVID-19: A post-mortem study.

Aims: To investigate cardiac pathology in critically ill patients with coronavirus disease 2019 (COVID-19) and identify associations between pathological changes and clinical characteristics. Methods: The present autopsy cohort study included hearts from 26 deceased patients hospitalized in intensive care units due to COVID-19, and was conducted at four sites in Wuhan, China. Cases were divided into a neutrophil infiltration group and a no-neutrophil group based on the presence or absence of histopathologically identified neutrophilic infiltrates. Results: Among the 26 patients, histopathological examination identified active myocarditis in four patients. All patients with myocarditis exhibited extensive accompanying neutrophil infiltration, and all patients without myocarditis did not. The neutrophil infiltration group exhibited significantly higher rates of detection of interleukin-6 (100 vs. 4.6%) and tumor necrosis factor-alpha (100 vs. 31.8%) than the no-neutrophil group (both p < 0.05). On admission, four patients with neutrophil infiltration in myocardium had significantly higher baseline levels of aspartate aminotransferase, D dimer, and high-sensitivity C reactive protein than the other 22 patients (all p < 0.05). During hospitalization, patients with neutrophil infiltration had significantly higher maximum creatine kinase-MB (median 280.0 IU/L vs. 38.7 IU/L, p = 0.04) and higher troponin I (median 1.112 ng/ml vs. 0.220 ng/ml, p = 0.56) than patients without neutrophil infiltration. Conclusion: Active myocarditis was frequently associated with neutrophil infiltration in the hearts of deceased patients with severe COVID-19. Patients with neutrophil-infiltrated myocarditis had a series of severely abnormal laboratory test results on admission, and high maximum creatine kinase-MB during hospitalization. The role of neutrophils in severe heart injury and systemic conditions in patients with COVID-19 should be emphasized.

Impact of proton pump inhibitors on the in-hospital outcome of COVID-19 patients: a retrospective study.

Background: Coronavirus disease 2019 (COVID-19) has triggered a global public health crisis. Proton pump inhibitors (PPIs) are one of the most commonly prescribed drugs. However, the effect of PPIs on the clinical outcomes of COVID-19 patients remains unclear. Methods: All COVID-19 patients admitted to the Wuhan Huoshenshan Hospital from February 2020 to April 2020 were retrospectively collected. Patients were divided into PPIs and non-PPIs groups. Logistic regression analyses were performed to explore the effects of PPIs on the outcomes of COVID-19 patients, including transfer to intensive care unit, mechanical ventilation, and death. Subgroup analyses were performed according to the presence of upper gastrointestinal symptoms potentially associated with acid and the routes, types, median total dosage, and duration of PPIs. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results: Of the 3024 COVID-19 patients included, 694 and 2330 were in PPIs and non-PPIs groups, respectively. Univariate logistic regression analysis showed that PPIs significantly increased the risk of reaching the composite endpoint in COVID-19 patients (OR = 10.23, 95% CI = 6.90-15.16, p < 0.001). After adjusting for age, sex, comorbidities, other medications, and severe/critical COVID-19, PPIs were independently associated with an increased risk of reaching the composite endpoint (OR = 7.00, 95% CI = 4.57-10.71, p < 0.001). This association remained significant in patients with upper gastrointestinal symptoms and those who received an intravenous omeprazole alone, but not those who received oral lansoprazole or rabeprazole alone. It was not influenced by dosage or duration of PPIs. Conclusion: The use of intravenous PPIs alone during hospitalization may be associated with worse clinical outcome in COVID-19 patients.

CREG ameliorates embryonic stem cell differentiation into smooth muscle cells by modulation of TGF-ß expression.

Vascular smooth muscle cell (SMCs) differentiation is critical for cardiovascular development, but the mechanisms remain largely unknown. The overall aim of this study was to investigate the functional impact and mechanism of cellular repressor of E1A-stimulated genes (CREG) in SMC differentiation. Two embryonic stem cell (ESC) models were generated (1) the overexpression of CREG (CREG-OE), by transfection with Pcreg-IRECS2-EGFP vector, and (2) the knockout of CREG, by transfection with CREG shRNA (CREG-KO). Interesting, SMC-marker levels (SM α-actin, SM22, Calponin, and SM-MHC) dramatically increased in CREG-OE ESCs into the SMC while significantly decreased in CREG-KO ESCs during differentiation. After 14 days, and calcium ion concentrations in angiotensin II-stimulated embryoid bodies were increased in CREG-OE ESCs but reduced in CREG-KO ESCs. Consistently, the contractile capacity of SMC from CREG-OE ESC was increased, while the contractile capacity of SMC CREG1 from CREG-KO ESCs was significantly reduced. Furthermore, we demonstrated that CREG promotes differentiation of ESCs to SMCs and maturation of their function through the transforming growth factor-ß -smad2/3 pathway.

Gastrointestinal Bleeding, but Not Other Gastrointestinal Symptoms, Is Associated With Worse Outcomes in COVID-19 Patients.

Background: Patients with coronavirus disease 2019 (COVID-19) can present with gastrointestinal (GI) symptoms. However, the prevalence of GI symptoms and their association with outcomes remain controversial in COVID-19 patients. Methods: All COVID-19 patients consecutively admitted to the Wuhan Huoshenshan hospital from February 2020 to April 2020 were collected. Disease severity and outcomes were compared between COVID-19 patients with and without GI symptoms. Logistic regression analyses were performed to evaluate the association of GI symptoms with the composite endpoint and death in COVID-19 patients. A composite endpoint was defined as transfer to intensive care unit, requirement of mechanical ventilation, and death. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results: Overall, 2,552 COVID-19 patients were included. The prevalence of GI symptoms was 21.0% (537/2,552). Diarrhea (8.9%, 226/2,552) was the most common GI symptom. Patients with GI symptoms had significantly higher proportions of severe COVID-19 and worse outcomes than those without. Univariate logistic regression analyses demonstrated that GI symptoms were significantly associated with the composite endpoint (OR = 2.426, 95% CI = 1.608-3.661; P < 0.001) and death (OR = 2.137, 95% CI = 1.209-3.778; P = 0.009). After adjusting for age, sex, and severe/critical COVID-19, GI symptoms were still independently associated with the composite endpoint (OR = 2.029, 95% CI = 1.294-3.182; P = 0.002), but not death (OR = 1.726, 95% CI = 0.946-3.150; P = 0.075). According to the type of GI symptoms, GI bleeding was an independent predictor of the composite endpoint (OR = 8.416, 95% CI = 3.465-20.438, P < 0.001) and death (OR = 6.640, 95% CI = 2.567-17.179, P < 0.001), but not other GI symptoms (i.e., diarrhea, abdominal discomfort, nausea and/or vomiting, constipation, acid reflux and/or heartburn, or abdominal pain). Conclusion: GI symptoms are common in COVID-19 patients and may be associated with their worse outcomes. Notably, such a negative impact of GI symptoms on the outcomes should be attributed to GI bleeding.

Comparison of liver biochemical abnormality between COVID-19 patients with liver cirrhosis versus COVID-19 alone and liver cirrhosis alone: A STROBE observational study.

ABSTRACT: Coronavirus disease (COVID-19) patients frequently develop liver biochemical abnormality. However, liver biochemical abnormality in COVID-19 patients with liver cirrhosis is under-recognized.Patients hospitalized during COVID-19 pandemic in China (ie, from February to April 2020) were screened. All of 17 COVID-19 patients with liver cirrhosis consecutively admitted to the Wuhan Huoshenshan Hospital were identified. Meanwhile, 17 age-, sex-, and severity-matched COVID-19 patients without liver cirrhosis admitted to this hospital were selected as a control group; all of 14 cirrhotic patients without COVID-19 consecutively admitted to the Department of Gastroenterology of the General Hospital of Northern Theater Command were selected as another control group. Incidence of liver biochemical abnormality and decompensated events were primarily compared.Among the COVID-19 patients with liver cirrhosis, the incidence of liver biochemical abnormality at admission and during hospitalization were 76.50% and 84.60%, respectively; 7 (41.20%) had decompensated events at admission; 1 was transferred to intensive care unit due to gastrointestinal bleeding. Among the COVID-19 patients without liver cirrhosis, the incidence of liver biochemical abnormality at admission and during hospitalization were 58.80% (P = .271) and 60.00% (P = .150), respectively. Among the cirrhotic patients without COVID-19, the incidence of liver biochemical abnormality at admission and during hospitalization were 69.20% (P = .657) and 81.80% (P = .855), respectively; 11 (78.60%) had decompensated events at admission (P = .036). None died during hospitalization among the three groups.Liver biochemical abnormality is common in COVID-19 patients with liver cirrhosis. Management of decompensated events in cirrhotic patients without COVID-19 should not be neglected during COVID-19 pandemic.

Chemokine CC-motif ligand 2 participates in platelet function and arterial thrombosis by regulating PKCα-P38MAPK-HSP27 pathway.

BACKGROUND: Studies indicate that chemokine CC-motif ligand 2 (CCL2) is involved in inflammation and atherosclerosis. However, the roles and mechanisms of CCL2 on platelet function and arterial thrombosis are unknown. METHODS: The expressions of CCL2 or CCR2 in the plasma, platelets and coronary thrombus of ST-elevated myocardial infarction (STEMI) patients were examined by ELISA, Western blot, immunohistochemistry and immunofluorescence. The roles of CCL2 on platelet aggregation, activation and secretion were examined by light transmission aggregometry, flow cytometry and ELISA. RESULTS: The expressions of CCL2 or CCR2 in the plasma or platelets of STEMI patients with platelet high response were higher than those with platelet normal response; In vitro, exogenous recombinant human CCL2 markedly increased platelet aggregation, activation and granule secretion, which were abolished by CCL2 neutralizing antibody or CCR2 inhibiter. CCL2 increased the phosphorylation levels of PKCα (Thr638), P38MAPK (Thr180/Tyr182) and HSP27 (S78/S82) in human platelets, which were abrogated by PKCα inhibitor (RO 318220) or P38MAPK inhibitor (SB 203580). RO 318220 or SB 203580 diminished CCL2-induced platelet function. In CCL2-/- mice, platelet aggregation and secretion were attenuated; the phosphorylation of PKCα, P38MAPK and HSP27 were decreased. In a carotid arterial thrombus mouse model, CCL2-/- mice displayed a significantly extended carotid artery occlusion time compared with wild type. CONCLUSIONS: CCL2 played important roles in regulating platelet function and arterial thrombosis through the PKCα-P38MAPK-HSP27 pathway, which might provide theoretical basis for searching new antiplatelet drugs and the treatment for cardiovascular diseases.

Transplantation of CREG modified embryonic stem cells improves cardiac function after myocardial infarction in mice.

Engraftment of embryonic stem cells (ESC) has been proposed as a potential therapeutic approach for post-infarction cardiac dysfunction. However, only mild function improvement has been achieved due to low survival rate and paracrine dysfunction of transplanted stem cells. Cellular repressor of E1A stimulated genes (CREG) has been reported to be a secreted glycoprotein implicated in promoting survival and differentiation of many cell types. Therefore we hypothesized that transplantation of genetically modified ESC with CREG (CREG-ESC) can improve cardiac function after myocardial infarction in mice. A total of 2 × 105 CREG-ESC or EGFP-ESC were engrafted into the border zone in a myocardial infarction model in mice. Cardiac function, infarct size and fibrosis at 4 weeks, survival of transplanted ESC, apoptosis and cytokine level of heart tissue, and teratoma formation were assessed in vivo. Apoptosis of ESC under inflammatory stimuli and cardiac differentiation of ESC were investigated in vitro. After 4 weeks, we found transplantation of CREG-ESC could significantly improve cardiac function, ameliorate cardiac remodeling, and reduce infarct size and fibrosis area. Transplantation of CREG-ESC remarkably increased ESC survival in the border zone and inhibited apoptosis of cardiomyocytes. Furthermore, the decrease of inflammatory factors (IL-1ß, IL-6 and TNF-α) and increase of anti-inflammatory factors (TGF-ß, bFGF and VEGF165) in the border zone were higher in CREG-ESC transplanted hearts. Safety evaluation showed that all transplantation at 2 × 105 per heart dose produced no teratoma. Surprisingly, the mice with 3.0 × 106 CREG-ESC transplantation was demonstrated teratoma free without cardiac rhythm disturbances in contrast to 100% teratoma formation and rhythm abnormality for the same dose of EGFP-ESC transplantation. In addition, overexpression of CREG inhibits ESC apoptosis and enhanced their differentiation into cardiomyocytes in vitro. Transplantation of CREG-modified ESC exhibits a favorable survival pattern in infarcted hearts, which translates into a substantial preservation of cardiac function after acute myocardial infarction.

Thrombin-loaded alginate-calcium microspheres: A novel hemostatic embolic material for transcatheter arterial embolization.

Transcatheter arterial embolization (TAE) is the best non-laparotomy choice for solid visceral organs rupture and bleeding nowadays. In our previous study, a new biodegradable macromolecule material thrombin-loaded alginate-calcium microsphere (TACM) was prepared and its characteristics were investigated preliminarily. In this study, we further investigated the biocompatibility of TACMs, as well as physical characteristic, application method and effect of TACMs with thrombus (embolic agent). The in vivo results attested that TACMs were non-irritating and non-genotoxic with desired biocompatibility, although brought about a slight and temporary inflammation. Application research showed that the function of thrombin was inhibited by common contrast agents, and it was impracticable to add contrast agents in TACMs with thrombus for tracing under X-rays in TAE. Then, a novel delivery method was developed. In addition, stress resistance test indicated that the TACMs with thrombus was significantly stronger than single autologous thrombus, the optimized ratio of TACMs to whole blood was 2:3 for forming mixed thrombus. Finally, large animal experiment revealed that the novel embolic agent - TACMs mixed thrombus was effective and safe in treating hemorrhage of solid abdominal viscera by TAE.

The impacts of different embolization techniques on splenic artery embolization for blunt splenic injury: a systematic review and meta-analysis.

BACKGROUND: Splenic artery embolization (SAE) has been an effective adjunct to the Non-operative management (NOM) for blunt splenic injury (BSI). However, the optimal embolization techniques are still inconclusive. To further understand the roles of different embolization locations and embolic materials in SAE, we conducted this system review and meta-analyses. METHODS: Clinical studies related to SAE for adult patients were researched in electronic databases, included PubMed, Embase, ScienceDirect and Google Scholar Search (between October 1991 and March 2013), and relevant information was extracted. To eliminate the heterogeneity, a sensitivity analysis was conducted on two reduced study sets. Then, the pooled outcomes were compared and the quality assessments were performed using Newcastle-Ottawa Scale (NOS). The SAE success rate, incidences of life-threatening complications of different embolization techniques were compared by χ2 test in 1st study set. Associations between different embolization techniques and clinical outcomes were evaluated by fixed-effects model in 2nd study set. RESULTS: Twenty-three studies were included in 1st study set. And then, 13 of them were excluded, because lack of the necessary details of SAE. The remaining 10 studies comprised 2nd study set, and quality assessments were performed using NOS. In 1st set, the primary success rate is 90.1% and the incidence of life-threatening complications is 20.4%, though the cases which required surgical intervention are very few (6.4%). For different embolization locations, there was no obvious association between primary success rate and embolization location in both 1st and 2nd study sets (P > 0.05). But in 2nd study set, it indicated that proximal embolization reduced severe complications and complications needed surgical management. As for the embolic materials, the success rate between coil and gelfoam is not significant. However, coil is associated with a lower risk of life-threatening complications, as well as less complications requiring surgical management. CONCLUSIONS: Different embolization techniques affect the clinical outcomes of SAE. The proximal embolization is the best option due to the less life-threatening complications. For commonly embolic material, coil is superior to gelfoam for fewer severe complications and less further surgery management.

Cellular Repressor of E1A-Stimulated Genes Is a Critical Determinant of Vascular Remodeling in Response to Angiotensin II.

OBJECTIVE: Cellular repressor of E1A-stimulated genes (CREG) is a lysosomal glycoprotein implicated in maintaining vascular homeostasis. Here, we have hypothesized that CREG is a critical target of intervention for the prevention of hypertensive vascular remodeling. APPROACH AND RESULTS: CREG gene expression was significantly decreased accompanied by an upregulated expression of angiotensin II (Ang II) in remodeled vascular tissues of high salt-induced Dahl salt-sensitive rats and Ang II-induced mice. In particular, the downregulation of CREG gene was Ang II specific and independent from blood pressure. Prominent medial hypertrophy and vascular fibrosis in both thoracic aortas and mesenteric arteries were observed in CREG+/- mice infused with Ang II than in CREG+/+ mice, but blunted response in CREG+/+ mice received recombinant human CREG protein, suggesting that changes in CREG expression account for the different phenotype between genotypes. Within a tiled promoter array, E26 transformation-specific-1 binds to CREG promoter at high stringency with the stimulation of Ang II. Moreover, the Ang II-induced E26 transformation-specific-1 directly interacted with the CREG promoter (-1179 and -271 bp) and inhibited its transcription in vascular smooth muscle cells. Selective, pharmacological inhibition of E26 transformation-specific-1 led to restoration of CREG expression in aortas and rescue of experimental vascular remodeling by systemic administration of dominant negative E26 transformation-specific-1 membrane-permeable peptides. CONCLUSIONS: CREG is a novel mediator of vascular remodeling in response to Ang II and may be an attractive therapeutic target for prevention of vascular diseases.

[Research progress of P75 neurotrophin receptor and new idea of nonunion treatment].

Objective: To review the research progress of P75 neurotrophin receptor (P75NTR) so as to clarify its mechanism, and to explore its relationship with nonunion so as to provide a new idea for the treatment of nonunion. Methods: The related domestic and foreign literature of P75NTR in recent years was extensively reviewed, summarized, and analyzed to find out the mechanism of action of P75NTR and the pathological factors of nonunion formation. Results: P75NTR can express in nonunion tissues and lead to defect of fibrin degradation and inhibition of angiogenesis, which play an important role in the pathogenesis of nonunion. Conclusion: It needs to be confirmed by further study whether the purpose of treating nonunion can be achieved by blocking the effects described above of P75NTR.

Melatonin attenuates postmyocardial infarction injury via increasing Tom70 expression.

Mitochondrial dysfunction leads to reactive oxygen species (ROS) overload, exacerbating injury in myocardial infarction (MI). As a receptor for translocases in the outer mitochondrial membrane (Tom) complex, Tom70 has an unknown function in MI, including melatonin-induced protection against MI injury. We delivered specific small interfering RNAs against Tom70 or lentivirus vectors carrying Tom70a sequences into the left ventricles of mice or to cultured neonatal murine ventricular myocytes (NMVMs). At 48 h post-transfection, the left anterior descending coronary arteries of mice were permanently ligated, while the NMVMs underwent continuous hypoxia. At 24 h after ischemia/hypoxia, oxidative stress was assessed by dihydroethidium and lucigenin-enhanced luminescence, mitochondrial damage by transmission electron microscopy and ATP content, and cell apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling and caspase-3 assay. At 4 weeks after ischemia, cardiac function and fibrosis were evaluated in mice by echocardiography and Masson's trichrome staining, respectively. Ischemic/hypoxic insult reduced Tom70 expression in cardiomyocytes. Tom70 downregulation aggravated post-MI injury, with increased mitochondrial fragmentation and ROS overload. In contrast, Tom70 upregulation alleviated post-MI injury, with improved mitochondrial integrity and decreased ROS production. PGC-1α/Tom70 expression in ischemic myocardium was increased with melatonin alone, but not when combined with luzindole. Melatonin attenuated post-MI injury in control but not in Tom70-deficient mice. N-acetylcysteine (NAC) reversed the adverse effects of Tom70 deficiency in mitochondria and cardiomyocytes, but at a much higher concentration than melatonin. Our findings showed that Tom70 is essential for melatonin-induced protection against post-MI injury, by breaking the cycle of mitochondrial impairment and ROS generation.

CREG protects from myocardial ischemia/reperfusion injury by regulating myocardial autophagy and apoptosis.

AIMS: Human cellular repressor of E1A-stimulated genes (CREG) is a secreted glycoprotein that regulates tissue and cell homeostasis and has been shown to antagonize heart fibrosis, which indicates a potential protective effect of CREG against cardiomyocyte chronic damage. However, little is known about the role of CREG in myocardial tissue acute injury, in this study, we aimed to investigate the role of CREG in myocardial ischemia/reperfusion (MI/R) injury and clarify the mechanism of action. METHODS AND RESULTS: Wild-type Creg (Creg+/+), heterozygous Creg (Creg+/-) mice and mice pretreated with infusion of recombinant 0.3mg/kg·d CREG protein (reCreg+/+) were subjected to 30min of left ascending coronary ischemia and 24h of reperfusion. Evan's Blue-triphenyl- tetrazolium chloride (TTC) solution and echocardiography analysis were used to evaluate the effects of CREG on MI/R mice. The underlying mechanisms were further determined by cultured myocardial cells in vitro. Our findings revealed that the level of CREG protein in mouse hearts was significantly decreased after mice were subjected to MI/R. Moreover, Creg+/- mice had larger infarction size 2h after reperfusion and worse cardiac function 28days after MI/R injury compared to that in Creg+/+ mice. However, reCreg+/+ mice could maintain CREG at a high level even after MI/R injury, and mitigated infarction size and improved cardiac function significantly. In Creg+/- mice, myocardial autophagy was dysfunctional characterized by accumulation of LC3A and p62, while apoptotic cell number increase was detected by cleaved caspase-3 blotting and TUNEL staining. Conversely, decreased apoptosis and activated autophagy were detected in reCreg+/+ mice. Furthermore, chloroquine, a kind of autophagy blocker, was used to demonstrate recombinant CREG protected cardiomyocytes against apoptosis mediated by activating autophagy both in vivo and in vitro. Finally, we found CREG was involved into lysosomal protein transfer and improve cellular autophagy. CONCLUSION: CREG protects heart against MI/R injury-induced cardiomyocytes apoptosis by activating lysosomal autophagy. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren and Megan Yingmei Zhang.

Cellular repressor of E1A-stimulated genes inhibits inflammation to decrease atherosclerosis in ApoE(-/-) mice.

AIMS: Macrophage inflammation response is important in the pathogenesis of atherosclerosis. We investigated the role and mechanism of cellular repressor of E1A-stimulated genes (CREG) in regulating TNF-α induced inflammation response in macrophages and explore whether CREG might be a therapeutic target for atherosclerosis. METHOD AND RESULTS: Immunostaining and western blotting showed that expression of CREG was reduced in human atherosclerotic coronary artery. In vivo experiments demonstrated that supplementation of recombinant CREG protein to ApoE(-/-) mice fed with high fat diet alleviated aortic atherosclerosis development and inflammation. In vitro, macrophage from ApoE(-/-) mice fed with high fat diet had lower level of CREG compared to control mice fed with normal diet. Immunohistochemical staining and western blotting further confirmed that CREG inhibited inflammatory response of macrophages induced by TNF-α. Supplementation of exogenous recombinant CREG protein or CREG gene silencing showed that CREG promoted autophagy in TNF-α treated macrophages. The use of autophagy inhibitors, 3-methyladenine and bafilomycin A, identified that CREG attenuated TNF-α induced inflammation by activate autophagy. In addition, supplementation of exogenous CREG protein stimulated expression and maturity of cathepsin B and cathepsin L and induced lysosome formation, whereas CREG deficiency reduced lysosomal formation. CONCLUSION: CREG inhibits inflammation and promotes autophagy mediated by lysosome formation; it might be a potential therapeutic target in atherosclerosis.