Abstract： Stem cell paracrine has been considered as the main mechanism to promote infarcted myocardium regeneration and repair of damaged cardiomyocytes. With further research, secreted frizzled-related protein 2 （Sfrp 2） and stem cell paracrine are closely linked to each other. Sfrp 2 can competitively bind to the specific receptor Fz in Wnt signaling pathway, inhibit Wnt signaling pathway to regulates apoptosis, differentiation, and other life processes of stem cells, and therefore becomes a research hotspot in recent years. This review focuses on the mechanism of Sfrp 2/Wnt signal way in stem cell therapy for myocardial infarction.
Objective To explore the induction of cardiomyogenesis of microRNA-129 （mir-129） in rat bone marrowmesenchymal stem cells （BM-MSCs） and its mechanism. Methods BM-MSCs were isolated from Sprague-Dawley rats and cultured in vitro. Overexpression of mir-129 or both mir-129 and glycogen synthase kinase-3β （GSK-3β） in BM-MSCs was produced with a lentiviral vector system. All the BM-MSCs were divided into four groups: control group （MSCs），Lentiviral vectors＋MSCs group （Lv-MSCs），mir-129 transfection group （mir-129-MSCs），and mir-129＋GSK-3βdouble transfection group （mir-129＋GSK-3β-MSCs）. Five-Azacytidine （5-Aza） （10 μmol/L） was used to induce BM-MSCsdifferentiation into cardiomyocytes. On the 1st，5 th，10 th，15 th and 20 th day after induction，realtime-PCR was performedto detect mRNA levels of GATA-4，Nkx2.5 and MEF-2C. On the 10 th，15 th and 20 th day after induction，Western blottingwas performed to examine expression levels of cTnI，Desmin，GSK-3β，phosphorylated β-catenin and dephosphorylated β-catenin. Results Compared with the control group，at respective time points，mRNA levels of cardiomyogenic genes and expression levels of cardiomyocyte-related proteins of mir-129 transfection group were significantly elevated，theexpression level of GSK-3β was significantly decreased，and the ratio of dephosphorylated/phosphorylated β-catenin was significantly elevated. When both mir-129 and GSK-3β were overexpressed in BM-MSCs，mRNA levels of cardiomyogenicgenes and expression levels of cardiomyocyte-related proteins were significantly lower than those of mir-129 transfection group，and the ratio of dephosphorylated/phosphorylated β-catenin was significantly decreased. Conclusion Overexpression of mir-129 can promote cardiomyogenesis of rat BM-MSCs possibly via inhibiting GSK-3β production and thus decreasing the inhibition of phosphorylation of β-catenin which then enters the nucleus and activates downstream signaling pathways that regulate cardiomyogenic differentiation of BM-MSCs.
Objective To study the short and medium term effect of myocardial contractile force by implantation of endothelial progenitor cells （EPCs） in the myocardial infarction model. Methods Hundred and twenty SD rats were equally and randomly divided into experimental group and control group （60 rats in each group）. Acute myocardial infarction model was created by ligation of LAD. Autologous EPCs were purified from peripheral blood then implanted into the acute myocardial infarct site via topical injection. IMDM were used in control group. Specimens and muscle strip were harvested at 3, 6 weeks, 6, 8 and 12 months after EPCs implantation for contractile force study and to detect the expression of vascular endothelial growth factor（VEGF）, basic fibroblast growth factor （bFGF） and Ⅷ factor by immunohistology and video image digital analysis system. Results The expression of VEGF, bFGF and the microvessel counts in experimental group were much higher than those of control group（P〈 0.01） at 3, 6 weeks and 6 months after transplantation. The contractile force in experimental group was better than that in control group（P〈0.01） at the same time. But from 8 months after implantation, the contractile force and so on were not up in the experimental group. Conclusion EPCs, after being implanted into infarct myocardium, shows the ability of improvement of the contractile performance in infarcted myocardium by means of angiogenesis and vasculogenesis and the medium term results are persistent.
ObjectiveTo investigate the effect of miR-190a-5p on the polarization of bone-marrow-derived macrophage (BMDM) induced by lipopolysaccharides to M1- and M2-types.MethodsBMDM (M1-type) induced by bacterial lipopolysaccharide was a M1 group. The macrophage M1-type interfered with negative control miRNA mimics was a NC group. miR-190a-5p mimics interfered with the M1-type of macrophages in the miR-190a-5p group. Morphological changes of macrophages were observed under a microscope, and the proportion of M2-type macrophages (CD206+, F4/80) was detected by flow cytometry. The mRNA expression levels of argininase-1 (Arg1), inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), target gene C/EBPα and PU.1 were detected by fluorescence quantitative PCR to verify whether C/EBPα and PU.1 were potential target genes of miR-190a-5p. The expression of pathway proteins C/EBPα and PU.1 were detected by Western blotting.ResultsAfter miR-190a-5p mimics interfered with macrophage M1-type, the antenna of macrophages elongated and showed long cord M2-type cell morphological characteristics. miR-190a-5p mimics interfered with M1-type macrophages for 24 h, and the percentage of M2-type macrophages increased significantly (P<0.05). Effects of miR-190a-5p simulator on mRNA expression levels of M1-type macrophages included: the expression of iNOS and TNF-α was significantly decreased (P<0.05), the expression of Arg1 marked by M2 macrophages was significantly increased (P<0.05), and the mRNA expression levels of target genes C/EBPα and PU.1 were significantly decreased (P<0.05). Western blotting results showed that the overexpression of miR-190a-5p significantly inhibited the protein expressions of C/EBPα and PU.1, while the miR-190a-5p inhibitor increased the expressions of both proteins.ConclusionmiR-190a-5p can promote the polarization of BMDM from M1-type to M2-type.
Objective To investigate the expression of miR-31a-5p in myocardial infarction (MI) mice and its potential mechanism. Methods A dataset was downloaded from the gene expression database, and miR-31a-5p and its predicted target gene hypoxia-inducible factor-1α (HIF-1α) were screened using bioinformatics methods. The MI model was established by ligating the left anterior descending branch of the coronary artery in C57BL/6J male mice which were randomly divided into sham and MI groups (n=6 in each group). The in vitro hypoxic cell model was induced by treatment of H9c2 cells with cobalt chloride (CoCl2) and divided into a control group, a model group, a NC group, a miR-31a-5p mimic group and a miR-31a-5p inhibitor group. The degree of myocardial tissue fibrosis was stained by Masson and analyzed. The expression levels of miR-31a-5p and HIF-1α mRNA in mouse myocardial tissues and H9c2 cells were detected by qRT-PCR. Western blotting was used to detect the expression levels of B-cell lymphoma 2 (Bcl-2), cleaved-caspase 3 apoptotic protein in mouse myocardial tissues and HIF-1α and apoptotic protein in H9c2 cells, respectively. The dual luciferase reporter gene assay was used to verify the targeting relationship between miR-31a-5p and HIF-1α. Results Masson staining showed significantly increased fibrosis in MI mice (P<0.000 1); miR-31a-5p, cleaved-caspase 3 were significantly elevated and Bcl-2 was decreased in MI mice and CoCl2 treated H9c2 (P<0.05). The results of dual luciferase reporter assay showed that the relative luciferase activity of miR-31a-5p mimic cotransfected with HIF-1α-3'-UTR WT plasmid was reduced (P<0.000 1); miR-31a-5p mimic decreased HIF-1α expression and increased apoptotic protein levels in CoCl2 induced H9c2 cells (both P<0.05), while miR-31a-5p exerted the opposite effect. Conclusion miR-31a-5p can aggravate apoptosis in myocardial ischemia by targeting HIF-1α.
Objective To investigate the prognosis and risk factors of cardiac surgical patients with preoperative renal dysfunction，and evaluate the accuracy of estimated glomerular filtration rate （eGFR） as a predictor of adverse outcomes. Methods A total of 2 151 adult patients undergoing cardiac surgery in Renji Hospital，School of Medicine of Shanghai Jiaotong University from January 2005 to December 2009 were included in this study. There were 1 267 male patientsand 884 female patients with their average age of 58.7 （18-99）years. Clinical characteristics of patients with preoperative renal dysfunction，severity of postoperative acute kidney injury （AKI）and patients’ outcomes were analyzed. Multivariate logistic regression was performed to analyze perioperative risk factors of postoperative AKI. Receiver operating characteristic（ROC） curve was used to evaluate the accuracy of eGFR to predict patients undergoing postoperative renal replacement therapy （RRT） and in-hospital death. Results A total of 221 patients （10.27%） had preoperative renal dysfunction，among whom 124 patients （56.11%） developed postoperative AKI. Patients with preoperative renal dysfunction were older，had more comorbidities including hypertension and diabetes mellitus，were more likely to receive postoperative RRT，and had worse outcomes. Patients with decreased preoperative eGFR had significantly higher in-hospital mortality. Patients with preoperative renal dysfunction who developed postoperative AKI had the worst prognosis. Multivariate logistic regression showed that hypertension （OR=4.497，P=0.003），postoperative central venous pressure （CVP） ＜6 cm H2O （OR=16.410，P=0.000） and postoperative CVP＞14 cm H2O （OR= 5.178，P=0.013） were independent predictors of postoperative AKI for patients with preoperative renal dysfunction. The areas under the ROC curves of eGFR to predict in-hospital mortality and postoperative RRT were 0.691 and 0.704 respectively （95% CI 0.630-0.752，P=0.000；95% CI 0.614-0.795，P=0.001）. Conclusion Patients with preoperative renal dysfunction are older，have more comorbidities，higher likelihood to develop postoperative AKI and worse prognosis. Hypertension，postoperative CVP＜6 cm H2O and postoperative CVP＞14 cm H2O are independent predictors of postoperative AKI for patients with preoperative renal dysfunction. We believe eGFR can accurately predict the risk of adverse kidney outcomes and in-hospital death of patients undergoing cardiac surgery.
Abstract： Objective To construct a nesprin-siRNA lentiviral vector（LV-siNesprin）, transfect it into bone marrow mesenchymal stem cells （MSCs）, and observe morphology changes of MSCs. Methods According to the target gene sequence of nesprin, we designed and synthesized four pairs of miRNA oligo, which were then annealed into double-strand DNA and identified by sequencing. MiRNA interference with the four kinds of plasmids （SR-1,SR-2,SR-3, andSR-4） were transfected into rat vascular smooth muscle cells, and reverse transcriptase chain reaction(RT-PCR) and Western blotting were performed to detect the interference effects and filter out the most effective interference sequence. We used the best interference sequence carriers and pDONR221 to react together to get the entry vectors with interference sequence. Then the objective carrier pLenti6/V5-DEST expressing both entry vectors and lentiviral vectors was restructured to get lentiviral expression vector containing interference sequence （LV-siNesprin＋green fluoresent protein （GFP））, which was packaged and the virus titer was determined. LV-siNesprin＋GFP was transfected to MSCs, and the expression of nesprin protein（LV-siNesprin＋GFP group，GFP control group and normal cell group）was detected by Western blotting. The morphology of MSCs nuclear was observed by 4’,6-diamidino-2-phenylindole （DAPI） stain. The proliferation of MSCs （LV-siNesprin＋GFP group，GFP control group and normal group） was detected by 3-(4,5-dimethylthia- zol-2-yl)-2,5-diphenyltetrazolium bromide（MTT） after lentivirus transfected to MSCs at 24, 48, 72, and 96 hours. Results The four pairs of miRNA oligo were confirmed by sequencing. Successful construction of LV-siNesprin was confirmed by sequencing. The best interference with miRNA plasmid selected by RT-PCR and Western blotting was SR-3. Lentiviral was packaged, and the activity of the virus titer of the concentrated suspension was 1×106 ifu/ml. After MSCs were transfected with LV-siNesprin, nesprin protein expression significantly decreased, and the nuclear morphology also changed including fusion and fragmentation. The proliferation rate of MSCs in the LV-siNesprin＋GFP group was significantly slower than that of the GFP control and normal cell groups by MTT. Conclusion Nesprin protein plays an important role in stabilizing MSCs nuclear membrane, maintaining spatial structure of MSCs nuclear membrane，and facilitating MSCs proliferation.
Objective To investigate clinical outcomes and perioperative management of off-pump coronary artery bypass grafting （OPCAB） for patients following acute myocardial infarction （AMI）.?Methods?From January 2006 to March 2010， 239 consecutive patients underwent OPCAB on the 14-27 （20.55±3.91） d following AMI（AMI group）in Renji Hospital，School of Medicine of Shanghai Jiaotong University. Preoperative MB isoenzyme of creatine kinase（CK-MB） level was （15.82±6.24） U/L and cardiac troponin I（cTnI） was （0.07±0.04） ng/ml. Clinical data of 406 patients without myocardial infarction history who underwent OPCAB during the same period were also collected as the control group for comparison.?Results?The 30-day mortality of AMI group was 2.51% （6/239）. The causes of death were circulatory failure in 4 patients， ischemic necrosis of lower extremity caused by intra-aortic balloon pump （IABP） in 1 patient and pneumonia with septic shock in 1 patient. Dopamine usage in AMI group was significantly higher than that of the control group （61.51% vs. 37.44%， P=0.001）. Intraoperative or postoperative IABP implantation was more common in AMI group， but there was no statistical difference between the two groups（P＞0.05） . Postoperative drainage and blood transfusion in AMI group were significantly larger than those of the control group （385.18±93.22 ml vs. 316.41±70.05 ml， P=0.022；373.68±69.54 ml vs. 289.78±43.33 ml， P=0.005， respectively）. But there was no statistical difference in re-exploration rate between the two groups （P＞0.05）. There was no statistical difference in the incidence of postoperative new onset atrial fibrillation between the two groups （P＞0.05）. Incidence of acute kidneyinjury of AMI group was significantly higher than that of the control group （13.81% vs. 8.62%， P=0.038）. Postoperative 30-day mortality of AMI group was higher than that of the control group， but there was no statistical difference between the two groups （2.51% vs. 1.48%，P＞0.05）. There was no statistical difference in ICU stay time and postoperative hospital stay between the two groups （2.01±0.95 d vs. 1.78±0.98 d；10.33±4.16 d vs. 9.89±4.52 d， respectively， P＞0.05）. A total of 211 patients （88.28%）in AMI group were followed up for 2.89±1.02 years， and 28 patients （11.72%） were lost during follow-up. Twenty-five patients died during follow-up including 14 cardiac deaths. One-year survival rate was 97.63%， and five-year survival rate was 88.15%.?Conclusion?It’s comparatively safe to perform OPCAB for patients at 2-4 weeks following AMI when their CK-MB and cTnI levels have returned to normal range.
Abstract： Objective To evaluate the incidence and prognosis of postoperative acute kidney injury （AKI） in patients after cardiovascular surgery， and analyse the value of AKI criteria and classification using the Acute Kidney Injury Network （AKIN） definition to predict their in-hospital mortality. Methods A total of 1 056 adult patients undergoing cardiovascular surgery in Renji Hospital of School of Medicine， Shanghai Jiaotong University from Jan. 2004 to Jun. 2007 were included in this study. AKI criteria and classification under AKIN definition were used to evaluate the incidence and in-hospital mortality of AKI patients. Univariate and multivariate analyses were used to evaluate preoperative， intraoperative， and postoperative risk factors related to AKI. Results Among the 1 056 patients， 328 patients（31.06%） had AKI. In-hospital mortality of AKI patients was significantly higher than that of non-AKI patients （11.59% vs. 0.69%， P＜0.05）. Multivariate logistic regression analysis suggested that advanced age （OR=1.40 per decade）， preoperative hyperuricemia（OR=1.97）， preoperative left ventricular failure （OR=2.53）， combined CABG and valvular surgery （OR=2.79）， prolonged operation time （OR=1.43 per hour）， postoperative hypovolemia （OR=11.08） were independent risk factors of AKI after cardiovascular surgery. The area under the ROC curve of AKIN classification to predict in-hospital mortality was 0.865 （95% CI 0.801-0.929）. Conclusion Higher AKIN classification is related to higher in-hospital mortality after cardiovascular surgery. Advanced age， preoperative hyperuricemia， preoperative left ventricular failure， combined CABG and valvular surgery， prolonged operation time， postoperative hypovolemia are independent risk factors of AKI after cardiovascular surgery. AKIN classification can effectively predict in-hospital mortality in patients after cardiovascular surgery， which provides evidence to take effective preventive and interventive measures for high-risk patients as early as possible.
ObjectiveTo describe our experiences of application of off-pump coronary artery bypass grafting surgery (OPCABG) in coronary artery disease (CAD) patients with dilated left ventricle.MethodsA retrospective analysis of 303 patients with dilated left ventricle [left ventricular end-diastolic diameter (LVEDD)> 60 mm] who underwent OPCABG from January 2008 to December 2018 at a single center was conducted. There were 205 males and 98 females at age of 45-87 (66.9±9.3) years.ResultsThe mean pulmonary artery pressure in 90 patients was more than 25 mm Hg. Sixteen patients underwent OPCABG with emergent transition of extracorporeal circulation (CPB). Twenty-one patients underwent OPCABG with CPB at the beginning of CABG. Thirty-five patients underwent intra-aortic balloon counterpulsation (IABP). Four patients died during in-hospital time with the experience of emergent transition of CPB. Six months after operation, LVEDD and left ventricular ejection fraction (LVEF) were improved.ConclusionOPCABG is a safe and effective alternative for CAD patients with dilated left ventricle. However, for patients with higher pulmonary pressure and a spherical left ventricle after cardiac reshaping, there is a high risk of emergent transition of CPB during OPCABG; for this kind of patients, it is necessary to start CPB at the beginning of OPCABG.