JMJD2A mediates transcriptional activation of SFRP4 and regulates oxidative stress and mitochondrial dysfunction in heart failure.

The importance of mitochondrial dysfunction and oxidative stress has been indicated in the progression of heart failure (HF). The molecular mechanisms, however, remain to be fully elucidated. This study aimed to explore the role and underlying mechanism of secreted frizzled-related protein 4 (SFRP4) in these two events in HF. Mice with HF were developed using transverse aortic constriction, and hematoxylin-eosin staining, MASSON staining, and Terminal deoxynucleotidyl transferase (TdT)-mediated 2'-Deoxyuridine 5'- Triphosphate nick end labeling (TUNEL assays) were conducted to detect morphological damage in the myocardial tissues of mice. HL-1 mouse cardiomyocytes were induced with isoproterenol (ISO), and cell viability and apoptosis were examined using cell counting kit-8 and TUNEL assays. SFRP4 and Jumonji domain-containing protein 2A (JMJD2A) were highly expressed in myocardial tissues. Suppression of SFRP4 alleviated apoptosis and fibrosis in myocardial tissues of mice. In addition, the extent of mitochondrial dysfunction and oxidative stress in damaged myocardial tissues and HL-1 cells was mitigated by SFRP4 inhibition as well. JMJD2A catalyzed demethylation modification of the SFRP4 promoter, thus promoting SFRP4 transcription in the development of HF. JMJD2A is responsible for SFRP4 transcription activation in the failing hearts of mice. Blockade of JMJD2A or SFRP4 might be a novel therapy effective in mitigating HF progression.

Glycolytic regulatory enzyme PFKFB3 as a prognostic and tumor microenvironment biomarker in human cancers.

The 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFK-2/FBPase-2, PFKFB3) is a glycolysis regulatory enzyme and plays a key role in oncogenesis of several cancers. However, the systematic study of crosstalk between PFKFB3 and Tumor microenvironment (TME) in pan-cancer has less been examined. In this study, we conducted a comprehensive analysis of the relationship between PFKFB3 expression, patient prognostic, Tumor mutational burden (TMB), Microsatellite instability (MSI), DNA mismatch repair (MMR), and especially TME, including immune infiltration, immune regulator, and immune checkpoint, across 33 types of tumors using datasets of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). We found that PFKFB3 expression was significantly correlated with patient prognostic and TME factors in various tumors. Moreover, we confirmed that PFKFB3 was an independent prognostic factor for kidney renal papillary cell carcinoma (KIRP), and established a risk prognostic model based on the expression of PFKFB3 as a clinical risk factor, which has a good predictive ability. Our study indicated that PFKFB3 is a potent regulatory factor for TME and has the potential to be a valuable prognostic biomarker in human tumor therapy.

HDAC1 Promotes Myocardial Fibrosis in Diabetic Cardiomyopathy by Inhibiting BMP-7 Transcription Through Histone Deacetylation.

OBJECTIVE: Diabetic cardiomyopathy (DCM) constitutes a primary cause of mortality in diabetic patients. Histone deacetylase (HDAC) inhibition can alleviate diabetes-associated myocardial injury. This study investigated the mechanism of HDAC1 on myocardial fibrosis (MF) in DCM. METHODS: A murine model of DCM was established by a high-fat diet and streptozotocin injection. The bodyweight, blood glucose, serum insulin, and cardiac function of mice were analyzed. Lentivirus-packaged sh-HDAC1 was injected into DCM mice and high glucose (HG)-induced cardiac fibroblasts (CFs). The pathological structure of the myocardium and the level of myocardial fibrosis were observed by histological staining. HDAC1 expression in mouse myocardial tissues and CFs was determined. Collagen I, collagen III, alpha-smooth muscle actin (α-SMA), and vimentin levels in CFs were detected, and CF proliferation was tested. HDAC activity and histone acetylation levels in tissues and cells were measured. Bone morphogenetic protein-7 (BMP-7) expression in myocardial tissues and CFs was determined. Functional rescue experiments were conducted to confirm the effects of histone acetylation and BMP-7 on myocardial fibrosis. RESULTS: DCM mice showed decreased bodyweight, elevated blood glucose and serum insulin, and cardiac dysfunction. Elevated HDAC1 and reduced BMP-7 expressions were detected in DCM mice and HG-induced CFs. HDAC1 repressed BMP-7 transcription through deacetylation. HDAC1 silencing alleviated MF, reduced CF proliferation and decreased collagen I, -III, α-SMA, and vimentin levels. However, reducing histone acetylation level or BMP-7 downregulation reversed the effects of HDAC1 silencing on CF fibrosis. CONCLUSION: HDAC1 repressed BMP-7 transcription by enhancing histone deacetylation, thereby promoting MF and aggravating DCM.

Evaluation of Cardiac Space-Occupying Lesions by Myocardial Contrast Echocardiography and Transesophageal Echocardiography.

Heart space-occupying lesions are a disease that occurs frequently in clinical setting, and therefore, it is important to diagnose and treat this type of pathologies properly. Angiographic echocardiography and transesophageal sonogram are widely used for clinical diagnosis. Their application provides a guarantee for the diagnosis of cardiac space-occupying lesions. In this paper, the application of cardiac contrast echocardiography and transesophageal echocardiography in cardiac space-occupying lesions was studied. Prediction of cardiac lesions can accurately determine the nature of cardiac occupancies and provide a basis for clinical diagnosis and management judgments. The results of pathological analysis and experimental comparison showed that myocardial contrast echocardiography can accurately distinguish tumor and thrombus and make contribution to patients taking appropriate medical measures. At the same time, it can compare conventional transthoracic echocardiography and transesophageal echocardiography. The results showed that TEE could clearly show the cardiac lesions. The experimental data of 76.9% confirmed cases showed that the diagnostic accuracy is greatly improved. TEE can also clearly show small thrombus that TTE cannot, in which 2DTEE can clearly show the boundary between the space-occupying and surrounding tissues, and whether there is a clear boundary between the space-occupying and surrounding tissues is an important distinguishing point of benign and malignant tumors. In addition, the TEE probe can also be used for large angle imaging and multiangle rotation, so as to determine the tumor boundary and the spatial position relationship between the tumor and the surrounding tissue. All in all, myocardial contrast echocardiography and transesophageal echocardiography have better clinical application effect on cardiac space-occupying lesions.

Overexpression of miR-1298 attenuates myocardial ischemia-reperfusion injury by targeting PP2A.

Previous studies reported that microRNA-1298 was abnormally expressed in the myocardium of rat hearts after hypoxia/normoxia injury. This study aims to investigate the function and specific mechanism of miR-1298 in myocardial ischemia/reperfusion (IR) injury. Neonatal rat cardiomyocytes (NRCMs) were isolated from neonatal rat hearts and subjected to oxygen/glucose deprivation/reperfusion (OGD/R) to induce I/R injury. The rat model with I/R injury was induced by ligating the proximal left anterior descending artery (LAD). MiR-1298 expression was detected by qRT-PCR. The levels of PP2A, Bcl-2, Bax, and AMPK signaling members (p-AMPK, p-GSK3ß) was detected by Western blot. Cell apoptosis was evaluated by TUNEL staining assay and flow cytometry. The infarct size of rat hearts was assessed by TTC staining assay. Premature and mature MiR-1298 were significantly downregulated while PP2A was significantly upregulated during I/R injury both in vitro and in vivo. The prediction of Starbase suggested that PP2A was a potential target of miR-1298. MiR-1298 overexpression significantly reduced cardiomyocyte apoptosis in vitro, and its protective effect was obviously attenuated by PP2A overexpression. Luciferase reporter assay showed that miR-1298 targeted PP2A directly. In addition, miR-1298 overexpression significantly reduced infarct size and cardiomyocyte apoptosis in the hearts of rats received with I/R injury in vivo. Moreover, miR-1298 overexpression significantly elevated the levels of Bcl-2 and AMPK signaling members (p-AMPK, p-GSK3ß) while decreased Bax level, and these effects were partially reversed by PP2A overexpression. MiR-1298 participated in myocardial I/R injury by targeting the PP2A/AMPK/GSK3ß signaling pathway, suggesting that miR-1298 might be a potential therapeutic target for myocardial I/R injury.

LncRNA H19 regulates smooth muscle cell functions and participates in the development of aortic dissection through sponging miR-193b-3p.

BACKGROUND: Multiple studies showed that long-chain noncoding RNA H19 (LncRNA H19) is high-expressed in human and mouse abdominal aortic aneurysms (AAAs). We speculated that it plays an important role in arterial disease, and therefore studied the role and mechanism of H19 in aortic dissection (AD). METHODS: The expressions of related genes in human aortic smooth muscle cells (HASMCs) induced by platelet-derived growth factor BB (PDGF-BB) or in the aortic tissue of AD patients/mice were identified by Western blot and quantitative real-time polymerase chain reaction. The targeting relationship between H19 and miR-193b-3p was predicted and verified by bioinformatics analysis, dual luciferase assay, RNA pull-down assay, RNA immunoprecipitation (RIP), and Pearson correlation coefficient. The H19 and miR-193b-3p effects on the biological functions of tissues and cells were examined by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, thiazolyl blue tetrazolium bromide) assay, wound-healing assay, and Hematoxylin-Eosin (HE) staining. RESULTS: LncRNA H19 was abnormally high-expressed in thoracic aorta tissues of AD patients, and it could competitively bind to and inhibit miR-193b-3p. In the PDGF-BB group, the expressions of H19, matrix metallopeptidase (MMP) 2 (MMP-2) and MMP-9 were up-regulated and the expressions of miR-193b-3p, α-SMA, and SM22α were down-regulated; moreover, the proliferation and migration rate of HASMCs were increased. However, H19 silencing reversed the regulation of PDGF-BB on HASMCs. More interestingly, miR-193b-3p inhibitor could partially reverse the effect of H19 silencing. In addition, the above results were verified by animal experiments, showing that shH19 and up-regulated miR-193b-3p could significantly reduce the thoracic aorta pathological damage in AD mice. CONCLUSION: LncRNA H19 regulated smooth muscle cell function by sponging miR-193b-3p and it participated in the development of AD.

Comparison of curative effect between different anticoagulation regimens in continuous renal replacement therapy after cardiac valve replacement. / 心脏瓣膜置换术后连续性肾脏替代治疗中不同抗凝方案的疗效比较.

OBJECTIVES: To compare the clinical effect of low molecular weight heparin (LMWH) and regional citrate anticoagulation (RCA) in continuous renal replacement therapy (CRRT) after heart valve replacement. METHODS: Retrospective analysis of clinical data from 60 patients undergoing continuous renal replacement therapy after heart valve replacement in Peking University Shenzhen Hospital from January 2015 to July 2019, including 35 males and 25 females, aged (58.83 ±16.36) years. The patients were divided into a LMWH group and a RCA group according to the anticoagulation regimen, with 30 patients in each group. The 24 h postoperative drainage volume (pericardium, mediastinum), postoperative ventilator use time and ICU stay time, incidence of postoperative respiratory tract bleeding and gastrointestinal bleeding, postoperative skin ecchymosis incidence and mortality between the 2 groups were compared; the thromboplastin time (APTT), fibrinogen (FIB), thrombin time (TT), prothrombin time (PT), international normalized ratio (INR), and PLT between the 2 groups after anticoagulation treatment were compared; the service life of dialysis filters and CRRT time between the 2 groups were compared; and the levels of urea nitrogen and serum creatinine between the 2 groups before and after treatment were also compared. RESULTS: After anticoagulant treatment, the RCA group had less 24 h postoperative drainage volume than the LMWH group, shorter ventilator use time, ICU stay time, and hospitalization days than the LMWH group, and lower respiratory tract bleeding and gastrointestinal bleeding incidence than the LMWH group, with significant differences (all P<0.05); there was no significant difference in the incidence of skin ecchymosis and mortality after treatment between the 2 groups (all P>0.05); there was no significant difference in APTT, FIB, and TT between the 2 groups (all P>0.05); the PT and INR of the RCA group were higher than those in the LMWH group, while the PLT of RCA group was lower than that in the LMWH group, with significant differences (all P<0.05); there was no significant difference in CRRT time between the two groups (P=0.073). After the treatment, there were no significant differences in urea nitrogen and serum creatinine levels between the 2 groups (all P>0.05). CONCLUSIONS: CRRT after cardiac valve replacement with RCA can effectively reduce pericardial and mediastinal drainage, reduce the risk of bleeding, shorten the time of ventilator use and ICU stay, and promote postoperative recovery of patients, which have positive significance for reducing the burden on patients and their families.

[Purification and characterization of two PR-10 protein isoforms from the crude drug of Angelica sinensis].

Two proteins of similar molecular weight (named as ASPR-C-1 and ASPR-C-2) from the crude drug of Angelica sinensis were purified and characterized by 80% ammonium sulfate precipitation, Sephadex G-50 gel filtration chromatography, and DEAE-Sepharose anion exchange chromatography. The molecular weight of ASPR-C-1 and ASPR-C-2 on SDS-PAGE was 17.33 kDa and 17.18 kDa, respectively. They were mainly monomeric in solution, but partially formed dimers and they were glycoproteins with glycosyl content of 2.6% and 8.2%, respectively. Both ASPR-C-1 and ASPR-C-2 were identified to be members of pathogenesis-related 10 family of proteins by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and have ribonuclease activities with the specific activity of 73.60 U/mg and 146.76 U/mg, respectively. The optimum pH of the two isoforms was similar, at about 5.6, while their optimum temperatures were different. The optimum temperature of ASPR-C-1 was 50 ℃, and that of ASPR-C-2 was 60 ℃. Both isoforms presented highest thermal stability at 60 ℃. However, ASPR-C-2 was more thermotolerant than ASPR-C-1. The latter was rapidly inactivated and retained only about 20% residual activity while the former still maintained about 80% of its original activity at a higher treatment temperature (80 to 100 ℃). In addition, Fe²âº had an activating effect on the ribonuclease activities of two isoforms while Ca²âº, Mg²âº, Zn²âº, Mn²âº, Ag⁺, Cu²âº, EDTA (Elhylene diamine tetraacetic acid), dithiothreitol and sodium dodecylsulphate showed different degrees of inhibition of the enzyme activities. Our findings provide a foundation for further research on the biological function of PR-10 protein from Angelica sinensis.

Mesoporous Silica Nanoparticles Rescue H2O2-induced Inhibition of Cardiac Differentiation.

The anti-oxidative property of mesoporous silica nanoparticles (MSNs) has been proposed previously, which prompted us to investigate the potential protective effect of MSNs on human embryonic stem cells (hESCs) against oxidative stress. To this purpose, the cell viability was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Apoptosis was analyzed by Annexin V/propidium iodide double-staining method. The intracellular glutathione, superoxide dismutase and malondialdehyde were measured with commercial assay kits. The reactive oxygen species was detected by staining with fluorescent dye DCFH-DA. The relative levels of Nkx2.5, Mef2c, Tbx5, dHand and α-MHC transcripts were measured by real-time polymerase chain reaction. The protein levels of Connexin 43, Troponin C1 and GAPDH were determined by immunoblotting. The beating behavior of embryoid bodies (EBs) was visually examined. Our results demonstrated that MSNs reversed hydrogen peroxide (H2O2)-inhibited cell viability and ameliorated H2O2-induced cell apoptosis in vitro. The H2O2-elicited intracellular oxidative stress was significantly relieved in the presence of MSNs. Furthermore, MSNs improved H2O2-suppressed differentiation of hESC-derived EBs and the maturation of the cardiomyocytes. In addition, MSNs treatment enhanced the beating properties of EBs. MSNs effectively conferred protection on hESCs against oxidative stress with respect to cardiac differentiation.Key words: Mesoporous silica nanoparticles, hydrogen peroxide, human embryonic stem cells, differentiation.

Purification and characterization of two pathogenesis-related class 10 protein isoforms with ribonuclease activity from the fresh Angelica sinensis roots.

In this study, two pathogenesis-related (PR) class 10 protein isoforms, ASPR-1 and ASPR-2, were purified from fresh roots of the Chinese medicinal plant Angelica sinensis (A. sinensis) using 80% ammonium sulfate precipitation, Sephadex G50 gel filtration chromatography, and DEAE-Sepharose ion-exchange chromatography. The molecular masses of ASPR-1 and ASPR-2 were estimated to be 16.66 kDa and 16.46 kDa, respectively, using sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The isoforms are both glycoproteins containing glycosyl contents of 1.8% (ASPR-1) and 3.4% (ASPR-2). The two isoforms were predominantly present as monomers, but they partially dimerized in solution. The 15 N-terminal amino acids of ASPR-1 were determined to be GIQKTEVEAPSTVSA, with significant sequence homology to certain PR-10 proteins. ASPR-2 was also identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) analysis to be a PR-10 protein. The isoforms both exhibited ribonuclease (RNase) activity, with ASPR-2 having higher specific activity (128.85 U mg-1) than ASPR-1 (68.67 U mg-1). The isoforms had the same optimal temperature of 50 °C but different optimal pH values of 5.0 (ASPR-1) and 6.0 (ASPR-2). The RNase activities of the isoforms were both stable for 30 min at 50 °C, rapidly decreasing at higher or lower processing temperatures. However, ASPR-1 retained higher residual activity (89.4%-80.9%) than ASPR-2 (74.3%-67.9%) at temperatures from 40 °C to 60 °C. These results provide additional information to enrich the current knowledge of poorly annotated A. sinensis proteins.

Role of VR1 in the differentiation of bone marrow-derived mesenchymal stem cells into cardiomyocytes associated with Wnt/ß-catenin signaling.

AIM: Accumulating evidence showed that transient receptor potential channels play an important role in the regulation of cardiomyocyte differentiation. The vanilloid receptor 1 (VR1) is a member of the transient receptor channel super family and is expressed in cardiomyocytes. However, its function in cardiomyocytes remains unclear. METHODS: Herein, the aim of this study was to investigate the functional role of VR1 in the cardiomyocyte differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and to elucidate the potential molecular mechanisms. RESULTS: Immunofluorescence assay showed that cardiomyocyte marker cardiac troponin T (cTnT) was found significantly elevated in differentiated BMSCs induced by 5-azacytidine compared with control. Similarly, VR1 expression was also found significantly increased in induced BMSCs differentiation. Additionally, we examined the role of VR1 in BMSC differentiation processes through VR1 siRNAs. We found that the expression of cardiomyocyte marker genes, such as alpha-myosin heavy chain (α-MHC), α-cardiac actin, and Nkx2.5 (cardiac-specific transcription factor), was significantly decreased when VR1 was silenced. Furthermore, we found that inhibition of VR1 expression is associated with downregulation of Wnt/ß-catenin signaling. CONCLUSIONS: To summarize, our data demonstrate important role of VR1 in BMSCs differentiation into cardiomyocytes in conjunction of Wnt/ß-catenin signaling.