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Objective To investigate the protective effect of glucose regulatory protein 78 ( GRP78) on cardiomyocytes in atrial fibrillation and its mechanism.Methods HL-1 cardiomyocyte cell line was cultured from June 2016 to March 2017 at Harbin Medical University Central Laboratory. The cells were randomly divided into 4 groups:control group, pacing group, pacing + GRP78cDNA group, pacing + GRP78siRNA group. The following indicators were detected:(1)oxidative stress:flow cytometry was used to detect the content of reactive oxygen species (ROS) in each group;(2)Ca2+ overload and cell electrophysiology:flow cytometry was used to detect Ca2+ content in each group; ( 3 ) cell structure reconstruction: cell apoptosis was detected by flow cytometry. Results The ROS production in the pacing group was significantly higher than that in the control group [(28.8 ± 0.5)% vs.(4.5 ± 0.8)%,F=27.91,P＜0.01].The number of ROS in the GRP78siRNA group was significantly higher than that in the pacing group [(71.1 ± 0.3%) vs.(28.8 ± 0.5)%,F=34.12,P＜0.01].The ROS content of the GRP78cDNA group was lower than that of the pacing group [(26.1 ± 2.7)% vs.(28.8 ± 0.5)%,F=26.60,P＜0.01].Pacing significantly increased Ca2+ concentration in HL-1 cells;GRP concentration in HL-1 cells in the GRP78siRNA group was significantly higher than that in the pacing group [(72.53 ± 2.5)AM vs.(39.23 ± 1.9)AM,F=19.50, P＜0.05].The intracellular Ca2+ concentration in the GRP78cDNA group was significantly lower than that in the pacing group [(31.23 ± 0. 57 ) AM vs.(39. 23 ± 1. 9 ) AM, F =28. 17, P ＜0. 01 ]. The survival rate of the GRP78cDNA group was significantly higher than that of the pacing group [(87.9 ± 0.4)% vs.(80.1 ± 0.5)%,F=19,P＜0.05].Conclusion GRP78 protein reduces intracellular calcium overload by reducing ROS production in myocardial cells during atrial fibrillation.It can alleviate the oxidative stress of cardiomyocytes and improve the survival rate of cardiomyocytes,and has protective effect on cardiomyocytes.
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Objective@#To investigate the protective effect of glucose regulatory protein 78 (GRP78) on cardiomyocytes in atrial fibrillation and its mechanism.@*Methods@#HL-1 cardiomyocyte cell line was cultured from June 2016 to March 2017 at Harbin Medical University Central Laboratory.The cells were randomly divided into 4 groups: control group, pacing group, pacing+ GRP78cDNA group, pacing+ GRP78siRNA group.The following indicators were detected: (1)oxidative stress: flow cytometry was used to detect the content of reactive oxygen species (ROS) in each group; (2)Ca2+ overload and cell electrophysiology: flow cytometry was used to detect Ca2+ content in each group; (3)cell structure reconstruction: cell apoptosis was detected by flow cytometry.@*Results@#The ROS production in the pacing group was significantly higher than that in the control group [(28.8±0.5)% vs.(4.5±0.8)%, F=27.91, P<0.01]. The number of ROS in the GRP78siRNA group was significantly higher than that in the pacing group [(71.1±0.3%) vs.(28.8±0.5)%, F=34.12, P<0.01]. The ROS content of the GRP78cDNA group was lower than that of the pacing group [(26.1±2.7)% vs.(28.8±0.5)%, F=26.60, P<0.01]. Pacing significantly increased Ca2+ concentration in HL-1 cells; GRP concentration in HL-1 cells in the GRP78siRNA group was significantly higher than that in the pacing group [(72.53±2.5)AM vs.(39.23±1.9)AM, F=19.50, P<0.05]. The intracellular Ca2+ concentration in the GRP78cDNA group was significantly lower than that in the pacing group [(31.23±0.57)AM vs.(39.23±1.9)AM, F=28.17, P<0.01]. The survival rate of the GRP78cDNA group was significantly higher than that of the pacing group [(87.9±0.4)% vs.(80.1±0.5)%, F=19, P<0.05].@*Conclusion@#GRP78 protein reduces intracellular calcium overload by reducing ROS production in myocardial cells during atrial fibrillation.It can alleviate the oxidative stress of cardiomyocytes and improve the survival rate of cardiomyocytes, and has protective effect on cardiomyocytes.
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Objective@#Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is a recently recognized high-risk T lymphoblastic leukemia subgroup. The optimal therapeutic approaches to adult patients with ETP-ALL are poorly characterized. In this study, we explore the efficacy and outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for ETP-ALL.@*Methods@#The clinical data of 23 patients with ETP-ALL receiving allo-HSCT from 2010 to 2018 were retrospectively analyzed. Patients with ETP-ALL were diagnosed based on the characteristic immunophenotypes. Second-generation sequencing was done in all patients. As to the donors, 12 patients had haploidentical donors (Haplo-HSCT) , 7 HLA-matched sibling donors (Sib-HSCT) and 4 HLA-matched unrelated donors (URD-HSCT) . Before transplantation, 19 patients achieved complete remission (CR) and 4 patients without.@*Results@#The main clinical features of ETP-ALL included high white blood cell counts in 5 patients, splenomegaly in 14, lymphadenopathy in 19, and thymus masses in 5. According to cytogenetic and molecular characteristics, 11 patients had gene mutations related to myeloid tumors, and 7 with high risk Karyotype. After first induction regimen, 14/23 patients achieved CR. 5 patients reached CR after more than 2 cycles of chemotherapy, while another 4 patients did not reach CR. After allo-HSCT, 22 patients were successfully implanted. The median time of granulocyte and platelet reconstitution was +12 and +19 days. One patient died of transplant-related infection at +14 days. The estimated 18-month overall survival (OS) and relapse-free survival (RFS) rates were (55.0±14.4) % and (48.1±14.7) % respectively. Transplant-related mortality was 4.3%. The median OS in patients achieving CR before transplantation was 20 months, however, that in patients without CR was only 13 months. OS and RFS between haplo-HSCT and sib-HSCT were comparable (P=0.460 and 0.420 respectively) .@*Conclusions@#Allo-HSCT is an effective therapy in some patients with ETP-ALL. Salvage HSCT cannot overcome the poor outcome. Haplo-HSCT and sib-HSCT in ETP-ALL patients have the similar clinical outcome.
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Objective To test whether cardiosphere-derived cells(CDCs)were sufficient to decrease manifestations of heart failure with preserved ejection fraction(HFpEF)in hypertensive rats.Methods DS rats(Charles River,Wilmington,Massachusetts)were fed 0.3% NaCl(low-salt)diet until 7 weeks of age.At that time,the diet was switched to an 8% NaCl(high-salt)diet in rats by random assignment.DS rats fed the low-salt diet constituted the control group(n=20).At 13 to 14 weeks of age,rats with the high-salt diet were randomized to receive allogeneic rat CDCs or PBS.Echocardiography long-axis images of the left ventricular systolic and diastolic dimensions.Sirius red was used to assess fibrosis and proliferation.Results E/A ratio increased in the PBS-treated group compared with the control group and the CDCs-treated group [(1.20±0.30)vs.(1.70±0.20)or(1.80±0.16),t=0.782,0.844,all P<0.001].LAA kept increasing in the PBS-treated group[(27.20±1.10)mm2 vs.(19.80±0.76)mm2 or(17.80±0.82)mm2,t=0.892,0.774,all P<0.001].The time constant of isovolumic LV pressure fall was prolonged in placebo-treated animals compared with CDCs-treated animals and control rats[(6.2±0.3)×103 mmHg/s vs.(9.4±0.4)×103 mmHg/s,t=0.382,P=0.024;(6.2±0.3)×103 mmHg/s vs.(9.1±0.5)×103 mmHg/s,t=0.883,P=0.022].LVEDP was 2-fold higher in placebo-treated group than in CDC-treated and control animals[(17±10)mmHg vs.(8±3)mmHg,t=0.922,P=0.003;(17±10)mmHg vs.(9±4)mmHg,t=0.922,P=0.004].A dramatic improvement of survival was observed in CDC-treated rats(Kaplan-Meier survival curves)(P=0.027).Cardiac myofibroblasts increased dramatically in PBS-treated(110/field vs.46/field,P<0.001).Inflammatory cytokines expression siginficantly increased in PBS-treated group.Conclusion CDCs improves survival in a rat model of HFpEF through reducing inflammation and fibrosis.
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Objective To investigate whether cardiosphere-derived cells (CDCs)can protect ischemia-reperfusion in acute myocardial infarction,and to explore its mechanism.Methods 7 -10 week-old female Wistar-Kyoto (WKY)rats were used for all in vivo experiment.Ischemia was induced for 45 min to allow reperfusion. Twenty minutes (or two hours)later,CDCs (or PBS control)were injected into the LV cavity with an aortic cross-clamp.After 48 hours and 2 weeks,representative echocardiography long-axis images of the left ventricular (LV) systolic and diastolic dimensions,the protein level of activated caspase-3 were observed,the apoptosis rate of myo-cardial cells and the infarct area of the heart were determined in those groups.Results Rats underwent 45 minutes of ischemia,followed by either 20 minutes or 120 minutes (delayed injection)of reperfusion prior to infusion of CDCs (cells per 100μL)or PBS control (100μL)into the LV cavity during aortic cross-clamp.Ejection fraction,as meas-ured by echocardiography,was significantly preserved in CDCs-treated animals at 48 hours with a 20 -minute,but not a 120-minute,delay of infusion(28.0% vs 38.0%,χ2 =7.340,P=0.008).CDCs-treated animals reduced percentage of infarct mass(6.2% vs 13.4%,χ2 =4.226,P=0.002;6.2% vs 13.5%,χ2 =1.853,P=0.003), infarct mass(6.2% vs 13.4%,χ2 =2.220,P=0.002;6.2% vs 13.5%,χ2 =3.119,P=0.003)treated with PBS control.CDC-treated animals reduced infarct size,relative to those of animals treated with PBS control(45.0% vs 24.0%,χ2 =4.825,P=0.008),less thinning of the LV anterior wall(1.96mm vs 1.45mm,t=0.897,P=0.028). Protein expressions of MMP-8 and CXGL7 were elevated in the infarct zone of hearts treated with CDCs(MMP-8:0.74 vs 0.56,t=0.657,P=0.014;CXGL7:0.44 vs 0.81,t=0.791,P=0.010).Conclusion CDCs is suggested to be a promising cell source to repair acute myocardial infarction through inhibiting apoptosis and reduce proinflam-matory cytokine expression.