Preliminary Study of Genome-Wide Association Identified Novel Susceptibility Genes for Hemorheological Indexes in a Chinese Population.

Background: Genome-wide association studies for various hemorheological characteristics have not been reported. We aimed to identify genetic loci associated with hemorheological indexes in a cohort of healthy Chinese Han individuals. Methods: Genotyping was performed using Applied Biosystems Axiom™ Precision Medicine Diversity Array in 838 individuals, and 6,423,076 single nucleotide polymorphisms were available for genotyping. The relations were examined in an additive genetic model using mixed linear regression and combined with identical by descent matrix. Results: We identified 38 genetic loci (p < 5 × 10-6) related to hemorheological traits. In which, LOC102724502-OLIG2 rs28371438 was related to the levels of nd30 (p = 8.58 × 10-07), nd300 (p = 1.89 × 10-06), erythrocyte rigidity (p = 1.29 × 10-06), assigned viscosity (p = 6.20 × 10-08) and whole blood high cut relative (p = 7.30 × 10-08). The association of STK32B rs4689231 for nd30 (p = 3.85 × 10-06) and nd300 (p = 2.94 × 10-06) and GTSCR1-LINC01541 rs11661911 for erythrocyte rigidity (p = 9.93 × 10-09) and whole blood high cut relative (p = 2.09 × 10-07) was found. USP25-MIR99AHG rs1297329 was associated with erythrocyte rigidity (p = 1.81 × 10-06) and erythrocyte deformation (p = 1.14 × 10-06). Moreover, the association of TMEM232-SLC25A46 rs3985087 and LINC00470-METTL4 rs9966987 for fibrinogen (p = 1.31 × 10-06 and p = 4.29 × 10-07) and plasma viscosity (p = 1.01 × 10-06 and p = 4.59 × 10-07) was found. Conclusion: These findings may represent biological candidates for hemorheological indexes and contribute to hemorheological study.

A Randomized Comparative Study on the Efficacy of Intracoronary Infusion of Autologous Bone Marrow Mononuclear Cells and Mesenchymal Stem Cells in Patients With Dilated Cardiomyopathy.

Stem cell therapy has shown therapeutic benefit in dilated cardiomyopathy (DCM), but doubt remains about the most appropriate stem cell subpopulation. The current study compared the efficacy of intracoronary administration of bone marrow mononuclear cells (BMMC) or mesenchymal stem cells (BMSC) in patients with DCM.Fifty-three patients with DCM and reduced (< 40%) left ventricular ejection fraction (LVEF), were randomized to intracoronary infusion of BMMC (BMMC group, n = 16) or BMSC (BMSC group, n = 17) or equal volume normal saline (CTRL group, n = 20). LVEF, New York Heart Association (NYHA) class, left ventricular end-diastolic diameter (LVEDd), and myocardial perfusion were assessed at baseline and at 3-month and 12-month follow-ups. Major adverse cardiovascular events (MACE) were also recorded.At the 3-month follow-up, LVEF, NYHA class, and myocardial perfusion had improved significantly in the BMSC group (P = 0.004, 0.020 and 0.019, respectively) along with significant changes in LVEF and NYHA class in the BMMC group compared with CTRL (P = 0.042 and 0.047, respectively), however, LVEDd remained unchanged. In comparison with CTRL, LVEF, NYHA class, and myocardial perfusion improved significantly in the BMSC group at the 12-month follow-up (P = 0.005, 0.050 and 0.038 respectively), but not in the BMMC group (P > 0.05). There were no significant differences between the transplantation groups during follow-up (P > 0.05). There were no differences in MACE among the 3 groups (P = 0.817).Intracoronary bone marrow stem cell transplantation in DCM is safe and effective, while BMSC and BMMC infusion possess comparable effectiveness.

Association between Serum Uric Acid and Liver Enzymes in Adults Aged 20 Years and Older in the United States: NHANES 2005-2012.

Although the relationship between serum uric acid (SUA) and nonalcoholic fatty liver disease has been widely reported, the relationship between SUA and liver enzymes has rarely been reported. The purpose of this study was to evaluate the association of SUA levels with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in populations aged 20 years and older in the United States. We analyzed 7165 individuals aged 20 years and older from the National Health and Nutrition Examination Survey (NHANES) in the United States. Weighted multiple linear regression models were used to analyze the relationship between SUA and ALT and AST. A generalized additive model and a smooth curve fitting were used to observe the linear relationship. SUA was positively correlated with ALT and AST. In addition, the overall increasing trend of ALT and SUA was observed across the SUA quartile groups. In the stratified analysis by sex and race, the SUA levels in male, female, Mexican American, and Non-Hispanic White individuals, and those of another race, were positively correlated with ALT and AST. However, the SUA levels in Non-Hispanic Black individuals had a nonlinear relationship with ALT and AST. In individuals aged 20 years and older in the United States (excluding Non-Hispanic Black individuals), SUA levels were positively associated with ALT and AST. Therefore, with a rise in SUA levels, liver function should be monitored or intervened with in people aged 20 years and older in the United States.

[Comparative study on the efficacy of intracoronary infusion with various types of autologous bone marrow stem cells for patients with dilated cardiomyopathy].

OBJECTIVE: To compare the effects of intracoronary infusion of mononuclear stem cells (MNCs) or mesenchymal stem cells (MSCs) in patients with dilated cardiomyopathy (DCM). METHODS: DCM patients with left ventricular ejection fraction(LVEF) < 40% were randomized to intracoronary infusion of MNCs [(5.1 ± 2.0) × 10(8), n = 16] or MSCs [(4.9 ± 1.7) × 10(8), n = 17] or equal volume normal saline (n = 20) through the guiding catheter. Changes of left ventricular end-diastolic diameter (LVEDd), LVEF and myocardium perfusion defects were assessed before and at (30 ± 3) days and (90 ± 7) days after the procedure. Malignant cardiovascular events were also recorded. RESULTS: (1) One month after the procedure, LVEF in transplantation groups significantly increased compared to before procedure (all P < 0.05), and significant increase of LVEF was observed only in MSCs transplantation group compared to control group (P < 0.05). However, absolute changes of LVEDd and perfusion defects of myocardium were similar among and within groups (P > 0.05). (2) Comparing with before procedure and control group, LVEF in transplantation groups increased significantly in three months after the procedure (P < 0.05), but there were no significant differences between transplantation groups (P > 0.05). LVEDd and myocardium perfusion defects in transplantation groups improved significantly compared with that of before procedure (P < 0.05), while significant decrease of myocardium perfusion defects was only observed in patients treated with MSCs compared with control group at three months after procedure (P < 0.05). (3) There were no significant differences in major cardiovascular events between transplantation group and control during follow-up (P > 0.05). CONCLUSIONS: Intracoronary bone marrow stem cells transplantation is safe and effective for DCM patients while the efficacy of MSCs and MNCs transplantation is comparable.

[Angiotensin(1-7) attenuates left ventricular dysfunction and myocardial apoptosis on rat model of adriamycin-induced dilated cardiomyopathy].

OBJECTIVE: To investigate the effect of Angiotensin(1-7) [Ang(1-7)] on left ventricular dysfunction and myocardial apoptosis on rat model of adriamycin-induced dilated cardiomyopathy (ADR-DCM). METHODS: Weight-matched adult male Wistar rats were randomly divided into 3 groups: (1) the ADR-DCM group (n = 25), in which 2.5 mg/kg of ADR was weekly intravenously injected for 10 weeks. (2) Ang(1-7) group (n = 25), in which ADR rats were simultaneously treated with angiotensin-(1-7) (24 µg×kg(-1)×h(-1), ip.) for 12 weeks. (3) normal control group (n = 10). Hemodynamics and echocardiography examination were performed at 12 weeks. The malondialdehyde (MDA) was measured by TBA methods. The plasma concentration of AngII was determined by immunoradiometric assay. The pathological change was analyzed by histological hematoxylin-eosin staining. Myocardial apoptosis was assessed by TUNEL method. The protein expression of pro-apoptotic protein caspase-3, Bax and anti-apoptotic protein Bcl-xl in cardiomyocytes were detected by Western blot. RESULTS: Mortality was significantly lower in Ang(1-7) group than in ADR-DCM group (16% vs. 40%, P < 0.01). Compared to the control group, left ventricular end-diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD) and left ventricular end-diastolic pressure (LVEDP) were significantly increased in ADR-DCM group (all P < 0.01) while fractional shorting (FS), +dp/dtmax and -dp/dtmax were significantly reduced in ADR-DCM group (all P < 0.01). LVEDD, LVESD and LVEDP were significantly reduced while FS, +dp/dtmax and -dp/dtmax were significantly higher in Ang(1-7) group compared to the ADR-DCM group, but still higher than the control group (all P < 0.01). The concentrations of AngII and MDA were higher in the ADR-DCM group than in the control group (P < 0.01), which were significantly reduced by Ang(1-7) treatment (P < 0.01). The TUNEL-positive cells and apoptosis index, the expression of pro-apoptotic protein caspase-3 and Bax were significantly higher while the expression of anti-apoptotic protein Bcl-xl was significantly lower in the ADR-DCM group than in the control group (all P < 0.01) which could all be partially reversed by Ang(1-7) treatment (all P < 0.01). CONCLUSION: Ang(1-7) could significantly attenuate left ventricular dysfunction and myocardial apoptosis in this model by downregulating pro-apoptotic protein caspase-3 and Bax and upregulating anti-apoptotic protein Bcl-xl expression.

Mesenchymal Stem Cell (MSC) Transplantation Accompanied by Activation of Invariant Natural Killer T Cells Further Ameliorates Post-infarct Cardiac Remodeling in Mice.

BACKGROUND: The purpose of this study was to examine the effect of mesenchymal stromal/stem cells (MSCs) on the infiltration of iNKT cells and further observe whether the activation of invariant natural killer T (iNKT) cells could assist the therapeutic action of MSCs on ventricular remodeling. METHODS: Mice with MI were used. qRT-PCR for Va14Ja18 (a special marker of iNKT cell for C57BL/6) was carried out. Gene expressions of Va14Ja18 were analyzed. Then, the experiment was performed in five groups: MI+Me, MI+MSCs, MI+MSCs+indome, MI+a-GC and MI+MSCs+a-GC. After 28 days, heart tissue fibrosis was accessed by Masson trichrome dyeing and apoptosis was evaluated by TUNEL staining and western blotting for caspase-3 protein. RESULTS: The number of iNKT cells infiltrating into the PLV significantly increased at day 7 after MI (1.72-fold changes from baseline, P<0.05), but almost returned to the baseline level at days 14 and 28. Compared to the MI+Me group (1.76±0.20-fold), iNKT cell infiltration was significantly suppressed at day 7 in MI+MSCs (1.25±0.29-fold, P<0.05) and MI+cMe groups (1.19±0.25-fold, P<0.05). In MI+cMe+indome and MI+cMe+PGE2 groups, the changes of iNKT cell infiltration were 1.74- and 1.04-fold, respectively (vs. 1.20-fold in the MI+cMe group, P<0.05). After the treatment by the combination of MSC transplantation and iNKT cell activation, myocyte apoptosis and interstitial fibrosis in PLV were both significantly attenuated. CONCLUSIONS: In the infarcted mouse model, MSCs suppressed the infiltration of iNKT cells by secreting PGE2. Activating iNKT cells could assist the therapeutic effect of MSCs on ventricular remodeling, with attenuated apoptosis and interstitial fibrosis. Therapies designed to activate iNKT cells before MSC transplantation might be beneficial to enhance the effectiveness of MSCs in the post-MI heart. This new approach brought forth from this study could offer a new path of immunotherapeutic interventions for infarcted hearts.

Inhibitory Effect of Vascular Endothelial Growth Factor on the Slowly Activating Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytes.

BACKGROUND: Vascular endothelial growth factor (VEGF) exerts a number of beneficial effects on ischemic myocardium via its angiogenic properties. However, little is known about whether VEGF has a direct effect on the electrical properties of cardiomyocytes. In the present study, we investigated the effects of different concentrations of VEGF on delayed rectifier potassium currents (IK) in guinea pig ventricular myocytes and their effects on action potential (AP) parameters. METHODS AND RESULTS: IK and AP were recorded by the whole-cell patch clamp method in ventricular myocytes. Cells were superfused with control solution or solution containing VEGF at different concentrations for 10 minutes before recording. Some ventricular myocytes were pretreated with a phosphatidylinositol 3-kinase inhibitor for 1 hour before the addition of VEGF. We found that VEGF inhibited the slowly activating delayed rectifier potassium current (IKs) in a concentration-dependent manner (18.13±1.04 versus 12.73±0.34, n=5, P=0.001; 12.73±0.34 versus 9.05±1.20, n=5, P=0.036) and prolonged AP duration (894.5±36.92 versus 746.3±33.71, n=5, P=0.021). Wortmannin, a phosphatidylinositol 3-kinase inhibitor, eliminated these VEGF-induced effects. VEGF had no significant effect on the rapidly activating delayed rectifier potassium current (IKr), resting membrane potential, AP amplitude, or maximal velocity of depolarization. CONCLUSIONS: VEGF inhibited IKs in a concentration-dependent manner through a phosphatidylinositol 3-kinase-mediated signaling pathway, leading to AP prolongation. The results indicate a promising therapeutic potential of VEGF in prevention of ventricular tachyarrhythmias under conditions of high sympathetic activity and ischemia.

Enhanced effect of VEGF165 on L-type calcium currents in guinea-pig cardiac ventricular myocytes.

The mechanisms of vascular endothelial growth factor 165 (VEGF165) on electrical properties of cardiomyocytes have not been fully elucidated. The aim of this study is to test the hypothesis that VEGF165, an angiogenesis-initiating factor, affects L-type calcium currents (ICa,L) and cell membrane potential in cardiac myocytes by acting on VEGF type-2 receptors (VEGFR2). ICa,L and action potentials (AP) were recorded by the whole-cell patch clamp method in isolated guinea-pig ventricular myocytes treated with different concentrations of VEGF165 proteins. Using a VEGFR2 inhibitor, we also tested the receptor of VEGF165 in cardiomyocytes. We found that VEGF165 increased ICa,L in a concentration-dependent manner. SU5416, a VEGFR2 inhibitor, almost completely eliminated VEGF165-induced ICa,L increase. VEGF165 had no significant influence on action potential 90 (APD90) and other properties of AP. We conclude that in guinea-pig ventricular myocytes, ICa,L can be increased by VEGF165 in a concentration-dependent manner through binding to VEGFR2 without causing any significant alteration to action potential duration. Results of this study may further expound the safety of VEGF165 when used in the intervention of heart diseases.

Over-expression of c-Myb increases the frequency of hemogenic precursors in the endothelial cell population.

Definitive hematopoiesis has been proposed to arise from hemogenic endothelial cells during mouse embryogenesis. The c-myb proto-oncogene is essential for the development of definitive hematopoiesis and was reported to be activated in hemogenic endothelial cells. To investigate whether c-Myb is involved in regulating the development of hemogenic endothelial cells, we conditionally induced c-myb over-expression during the in vitro differentiation of embryonic stem cells. VE-cadherin+ CD45- cells inducibly expressing c-Myb showed an increase in multilineage colony formation as well as an augmented capacity of the colony forming cells to self-renew in vitro under the condition that only the endogenous c-myb gene was expressed during differentiation of hematopoietic cells. Over-expression of c-Myb in the endothelial population led to activation of genes associated with definitive hematopoiesis such as Runx1, Hoxb4, Mll and Etv6. Our data provide evidence that c-Myb is able to exert an effect in endothelial cells which fosters the establishment of their hemogenic potential.

Proper levels of c-Myb are discretely defined at distinct steps of hematopoietic cell development.

The definitive hematopoietic cell lineages have been proposed to originate from hemogenic endothelial cells during mouse embryogenesis. c-Myb is a transcription factor that is essential for the development of definitive hematopoiesis. To investigate the functional role of c-Myb in hematopoietic cell development from endothelial cells, we introduced a c-myb transgene expressed under the control of a tetracycline-regulated promoter into the c-myb(-/-) embryonic stem (ES) cell line, with the aim of inducing c-Myb expression at any stage and at any level. Induction of c-Myb expression after replating c-myb(-)(/)(-) endothelial cells rescued the generation and proliferation of definitive hematopoietic progenitor cells, suggesting that c-Myb expression in developing endothelial cells is not a prerequisite for their hematogenic potential. Overexpression of c-Myb, however, prevented the terminal differentiation of erythrocytes and megakaryocytes and completely abolished B-lymphocyte development. Our results indicate that c-Myb is a major factor that controls differentiation as well as proliferation of hematopoietic progenitor cells derived from hemogenic endothelial cells, and that appropriate levels of c-Myb protein are strictly defined at distinct differentiation steps of each hematopoietic cell lineage.