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Objective: To quantitatively investigate the effects of Ringer's solution with different concentrations of alcohol (1%～80%) on biphasic compound action potentials (AP) from frog sciatic nerve trunk, and their recoveries from alcohol effects., Methods: Individual segments of frog sciatic nerve trunk with a length of 6 to 8 cm were prepared. Ringer's solution with different concentrations of alcohol (0%, 1%, 2%, 4%, 8%, 16%, 32%, 48%, 64% and 80%) was applied onto the segment of the trunk between the stimulus and ground electrodes via an agent reservoir which was newly armed in a nerve trunk shielded chamber for 5 minutes. The nerve trunk was respectively electro-stimulated to generate the biphasic compound AP which was recorded using the experimental system of BL-420F. This was followed by 5 times washout plus 5 min administration with Ringer's solution before recovery recording of AP., Results: Compared to normal Ringer's solution, Ringer's solution with alcohol at ≤4% did not have dramatic impacts on the AP amplitude and conduction velocity, while Ringer's solution with alcohol at ≥8% there was significant decrease in these two parameters. Ringer's solution with alcohol at the conentrations of 16%, 32% and ≥48% could prevent a small proportion (30%), a large proportion (90%) and all (100%) of sciatic nerve trunks, respectively, from generating AP. Washout with normal Ringer's solution after alcohol application at the concentration of ≤32%, AP could totally recover to normal status. While alcohol at the concentration of 48%, 64% and 80%, the probabilities to regenerate APs were 90%, 40% and 0%, and the AP amplitudes were decreased to 60%, 36% and 0%, respectively. After washout, AP conduction velocity showed no difference with alcohol at the concentration of ≤8% when compared with that before washout, while it could not be recovered to normal under alcohol at ≥16%., Conclusion: Ringer's solution with different concentrations of alcohol exerts different effects on biphasic compound AP amplitude and conduction velocity. Hopefully, our findings could be helpful for the alcoholic usage and its recovery from alcoholic damage.

Background: Ca2+ plays an important role in the regulation of vasoconstriction. Ca2+ signaling is regulated by a number of Ca2+-handling proteins. However, whether differences in Ca2+ handling affect the regulation of vasoconstriction in different arteries remains elusive., Objective: To determine whether differences in Ca2+ handling affect the response to vasoconstrictors in different arteries., Methods: Arterial ring contraction was measured using a Multi Myograph System. Vascular smooth muscle cells (VSMCs) were digested with type 2 collagenase in DMEM, then intracellular calcium concentration was measured with the Ca2+ probe fluo-4/AM in the isolated cells. Calcium-related proteins were assayed by Western blotting., Results: Phenylephrine did not induce -coronary arterial contraction. There were differences in -5-hydroxytryptamine, 9,11-dideoxy-11a,9a-epoxymethano-prostaglandin F2a, and endothelin 1-induced vasoconstriction in different solutions between coronary and renal arteries. Vasoconstrictions in the presence of Bay K8644 were stronger in coronary than in renal arteries. Store-operated calcium (SOC) channels could mediate Ca2+ influx in VSMCs of both groups. SOC channels did not participate in the contraction of coronary arteries. In addition, there were significant differences in the expressions of receptors and ion channels between the two groups., Conclusions: Ca2+ handling contributed to the different responses to vasoconstrictors between coronary and renal arteries., (© 2019 S. Karger AG, Basel.)

The molecular mechanisms underlying anthracyclines-induced cardiotoxicity have not been well elucidated. MiRNAs were revealed dysregulated in the myocardium and plasma of rats received Dox treatment. MicroRNA-34a-5p (miR-34a-5p) was verified increased in the myocardium and plasma of Dox-treated rats, but was reversed in rats received Dox plus DEX treatments. Human miR-34a-5p was also observed increased in the plasma of patients with diffuse large B-cell lymphoma after 9- and 16-week epirubicin therapy. Up-regulation of miR-34a-5p was observed in Dox-induced rat cardiomyocyte H9c2 cells. MiR-34a-5p could augment Bax expression, but inhibited Bcl-2 expression, along with the increases of the activated caspase-3 and mitochondrial potentials in H9C2 cells. MiR-34a-5p was verified to modulate Sirt1 expression post-transcriptionally. In parallel to Sirt1 siRNA, miR-34a-5p could enhance p66shc expression, accompanied by increases of Bax and the activated caspase-3 and a decrease of Bcl-2 in H9c2 cells. Moreover, enforced expression of Sirt1 alleviated Dox-induced apoptosis of H9c2 cells, with suppressing levels of p66shc, Bax, the activated caspase-3 and miR-34a-5p, and enhancing Bcl-2 expression. Therefore, miR-34a-5p enhances cardiomyocyte apoptosis by targeting Sirt1, activation of miR-34a-5p/Sirt1/p66shc pathway contributes to Dox-induced cardiotoxicity, and blockage of this pathway represents a potential cardioprotective effect against anthracyclines.

The role of microRNA-214-3p (miR-214-3p) in cardiac fibrosis was not well illustrated. The present study aimed to investigate the expression and potential target of miR-214-3p in angiotensin II (Ang-II)-induced cardiac fibrosis. MiR-214-3p was markedly decreased in the fibrotic myocardium of a mouse Ang-II infusion model, but was upregulated in Ang-II-treated mouse myofibroblasts. Cardiac fibrosis was shown attenuated in Ang-II-infused mice received tail vein injection of miR-214-3p agomir. Consistently, miR-214-3p inhibited the expression of Col1a1 and Col3a1 in mouse myofibroblasts in vitro. MiR-214-3p could bind the 3'-UTRs of enhancer of zeste homolog 1 (EZH1) and -2, and suppressed EZH1 and -2 expressions at the transcriptional level. Functionally, miR-214-3p mimic, in parallel to EZH1 siRNA and EZH2 siRNA, could enhance peroxisome proliferator-activated receptor-γ (PPAR-γ) expression and inhibited the expression of Col1a1 and Col3a1 in myofibroblasts. In addition, enforced expression of EZH1 and -2, and knockdown of PPAR-γ resulted in the increase of Col1a1 and Col3a1 in myofibroblasts. Moreover, the NF-κB signal pathway was verified to mediate Ang-II-induced miR-214-3p expression in myofibroblasts. Taken together, our results revealed that EZH1 and -2 were novel targets of miR-214-3p, and miR-214-3p might be one potential miRNA for the prevention of cardiac fibrosis.

The L-type calcium channel (LCC) plays a regulatory role in various physical and pathological processes. In the vasculature, LCCs mediate agonist-induced vascular smooth muscle contraction. However, whether LCC-mediated vessel responses to certain vasoconstrictors vary among species remains unclear. The coronary arteries were dissected from the hearts of rats and mice. Coronary arterial ring contraction was measured using the Multi Myograph system. High K+ (60 mM)-induced coronary artery contractions were stronger in rats than in mice, whereas CaCl2-induced contraction curves did not differ significantly between the two groups. Endothelin-1, U46619 (thromboxane A2 receptor agonist), and 5-hydroxytryptamine (5-HT) induced concentration-dependent vasoconstriction of coronary arterial rings in rats and mice. The vessel rings of mice were more sensitive to ET-1 and U46619 and less sensitive to 5-HT than those of rats. The LCC blocker nifedipine significantly inhibited coronary artery contractions induced by ET-1, U46619, and 5-HT. The inhibitory effect of 1 μM nifedipine on ET-1- and 5-HT-induced coronary artery contractions was stronger in mice than in rats, whereas its effect on U46619-induced vessel contractions was weaker in mice than in rats. The 5-HT2A receptor and LCC mRNA levels were higher in the coronary arteries of rats than in those of mice, whereas the expressions of the ETA and TXA2 receptors and Orai1 mRNA levels were comparable between the two groups. LCC plays an important role in coronary arterial contraction. Rats and mice show different responses to vasoconstrictors and LCC blockers, suggesting that the coronary arteries of rats and mice have different biological characteristics.

Cyclins/retinoblastoma protein (pRb) pathway participates in cardiomyocyte hypertrophy. MicroRNAs (miRNAs), the endogenous small non-coding RNAs, were recognized to play significant roles in cardiac hypertrophy. But, it remains unknown whether cyclin/Rb pathway is modulated by miRNAs during cardiac hypertrophy. This study investigates the potential role of microRNA-16 (miR-16) in modulating cyclin/Rb pathway during cardiomyocyte hypertrophy. An animal model of hypertrophy was established in a rat with abdominal aortic constriction (AAC), and in a mouse with transverse aortic constriction (TAC) and in a mouse with subcutaneous injection of phenylephrine (PE) respectively. In addition, a cell model of hypertrophy was also achieved based on PE-promoted neonatal rat ventricular cardiomyocyte and based on Ang-II-induced neonatal mouse ventricular cardiomyocyte respectively. We demonstrated that miR-16 expression was markedly decreased in hypertrophic myocardium and hypertrophic cardiomyocytes in rats and mice. Overexpression of miR-16 suppressed rat cardiac hypertrophy and hypertrophic phenotype of cultured cardiomyocytes, and inhibition of miR-16 induced a hypertrophic phenotype in cardiomyocytes. Expressions of cyclins D1, D2 and E1, and the phosphorylated pRb were increased in hypertrophic myocardium and hypertrophic cardiomyocytes, but could be reversed by enforced expression of miR-16. Cyclins D1, D2 and E1, not pRb, were further validated to be modulated post-transcriptionally by miR-16. In addition, the signal transducer and activator of transcription-3 and c-Myc were activated during myocardial hypertrophy, and inhibitions of them prevented miR-16 attenuation. Therefore, attenuation of miR-16 provoke cardiomyocyte hypertrophy via derepressing the cyclins D1, D2 and E1, and activating cyclin/Rb pathway, revealing that miR-16 might be a target to manage cardiac hypertrophy., (© 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a desmosomal disease. Desmosomes and gap junctions are important structural components of cardiac intercalated discs. The proteins plakophilin-2 (PKP-2) and connexin43 (Cx43) are components of desmosomes and gap junctions, respectively. This study was conducted to determine whether Cx43 expression is affected by the mutation of the PKP-2 gene in patients with ARVC. A novel mutation was detected in a typical patient with ARVC. The mutated gene was transfected into rat mesenchymal stem cells expressing Cx43 through a pReversied-M-29 plasmid. Cx43 expression was detected using quantitative polymerase chain reaction analysis. Cx43 expression was significantly decreased in the mutant PKP-2 group compared with that in the wild-type PKP-2 group. In conclusion, PKP-2 affected Cx43 expression at the gene transcription level in the patient with ARVC.

The T-type Ca(2+) current (I(Ca,T)) plays an important role in the pathogenesis of atrial fibrillation (AF). The present study sought to investigate the role of macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, in the regulation of T-type Ca(2+) channels (TCCs) in atrial myocytes. We used the whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I(Ca,T) in atrial myocytes. Gene levels of the α1G and α1H subunit of TCCs were decreased in human atrial tissue of patients with AF. In cultured atrium-derived myocytes (HL-1 cells), mouse recombinant MIF (20 or 40 nm, 24 h) suppressed peak I(Ca,T) in a concentration-dependent manner, impaired the voltage-dependent activation of I(Ca,T) and downregulated TCC α1G and α1H mRNA. The Src inhibitors genistein and PP1 significantly enhanced I(Ca,T). The reduction of I(Ca,T) and TCC subunit mRNA induced by recombinant MIF could be reversed by genistein and PP1. The TCC α1G associated with Src in HL-1 cells and mouse cardiomycytes. Macrophage migration inhibitory factor is involved in the pathogenesis of AF, probably by decreasing the T-type calcium current in atrium-derived myocytes through impairment of channel function and activation of c-Src kinases, representing a potential pathogenic mechanism in atrial fibrillation.

To characterize the pollution characteristics of microbial aerosols emitted from municipal sewage treatment plants, microbial aerosols were sampled with an Andersen 6-stage impactor at different treatment units of a Xi'an sewage treatment plant between June 2011 and July 2011. The plate-culture and colony-counting methods were employed to determine the concentrations, particle size distributions and median diameters of the airborne bacteria, fungi and actinomycetes. The results showed that the highest concentrations of bacteria (7 866 CFU x m(-3) +/- 960 CFU x m(-3)) and actinomycetes (2 139 CFU x m(-3) +/- 227 CFU x m(-3)) were found in the sludge-dewatering house while the highest fungi concentration (2156 CFU x m(-3) +/- 119 CFU x m(-3)) in the oxidation ditch. The airborne bacteria, fungi and actinomycetes all showed a skewed distribution in particle size. The peaks of bacteria and fungi were in the size range of 2.1-3.3 microm, whereas the peak of airborne actinomycetes was between 1. 1-2.1 microm in size. In general, the order of the median diameters of different microbial aerosols generated from the sewage treatment plant was airborne bacteria > airborne fungi > airborne actinomycetes. In addition, the spatial variation characteristics of microbial aerosols showed that the larger the particle size of the microorganism, the faster the reducing rate of the aerosol concentration. The variations in the reducing rate of concentration with particle sizes can be ordered as airborne bacteria > airborne fungi > airborne actinomycetes.

Objective: To study the changes of tissue composition and immunogenicity of porcine and human aortic valves after decellularization., Methods: Three cryopreserved human aortic valves and 4 porcine valves were decellularized with trypsin, and the leaflet tissue was homogenized for SDS-PAGE protein electrophoresis and U-937 migration assay., Results: Trypsin effectively removed the cells from the valve. SDS-PAGE demonstrated an obvious difference in the tissue composition between porcine and human valves. Although decellularization significantly diminished the differences between the valves, decellularized procine aortic valve stilled contained more protein components (between 26 000 and 43 000) than human valve. U-937 migration assay showed an obvious decrease of cell migration in the valves by decellularization (from 832.7×10(3) to 152.4∓31.1×10(3) for porcine valves, P<0.01, and from 644.9×10(3) to 91.2×10(3) for the human valves, P<0.01). Decellularized porcine valves induced a significantly greater cell migration than decellularized human valves (P<0.05)., Conclusion: Decellularization with trypsin can effectively decrease the immunogenicity of human or porcine heart valve, but can not completely eliminate the antigen, and decellularized porcine valve still retain strong immunogenicity.

Background: The effect of impaired glucose tolerance (IGT) on cardiac function during the chronic prediabetes state is complicated and plays an important role in clinical outcome. However, the molecular mechanisms are not fully understood. This study was designed to observe cardiac dysfunction in prediabetic rats with IGT and to determine whether glucose metabolic abnormalities, inflammation and apoptosis are linked to it., Methods: The IGT rat models were induced by streptozocin, and the heart functions were assessed by echocardiography. Myocardial glucose metabolism was analyzed by glycogen periodic acid-Schiff staining, and the pro-apoptotic effect of IGT was evaluated by TUNEL staining. Additionally, caspase-3 activation, macrophage migration inhibitory factor (MIF) and G-protein coupled receptor kinase 2 (GRK2) were detected by Western blotting in cardiac tissue lysates., Results: Area-under-the-curve of blood glucose in rats injected with streptozotocin was higher than that in controls, increased by 16.28%, 38.60% and 38.61% at 2, 4 and 6 weeks respectively (F = 15.370, P = 0.003). Abnormal cardiac functions and apoptotic cardiomyocytes were observed in the IGT rats, the ejection fraction (EF) being (68.59 ± 6.62)% in IGT rats vs. (81.07 ± 4.59)% in controls (t = 4.020, P = 0.002). There was more glucose which was converted to glycogen in the myocardial tissues of IGT rats, especially in cardiac perivascular tissues. Compared to controls, the cleaved caspase-3, MIF and GRK2 were expressed at higher levels in the myocardial tissues of IGT rats., Conclusions: IGT in the prediabetes period resulted in cardiac dysfunction linked to abnormal glycogen storage and apoptosis. Additionally, MIF and GRK2 may be involved in the pathogenesis of cardiac dysfunction in prediabetes and their regulation may contribute to the design of novel diagnostic and therapeutic strategies for those who have potential risks for diabetic cardiovascular complications.

Objective: To investigate the effect of ginsenoside Rg1 on the microenvironment dependent differentiation of human mesenchymal stem cells (hMSCs) to vaso-endothelioid cells (VECs) in vitro., Methods: The in vitro differentiation of hMSCs to VECs were established adopting the in vivo environment simulated semi-permeable membrane separated non-contact co-culturing method. The mRNA expressions of endothelial markers, such as platelet endothelial adhesive factor-1 (CD31), vascular hemophillia factor (vWF) and vascular endothelial cadherin (VE-cadherin) were analyzed by RT-PCR; the protein expressions of CD31 and vascular endothelial adhesive factor-1 (VCAM1) were detected by fluorescence immunohistochemistry; structural identification for the endothelial characteristics of differentiated hMSCs were made under electron microscopy; and the percentage of CD31 expression in differentiated hMSCs was determined by flow cytometry to explore the effect of ginsenoside Rg1 on the differentiation., Results: The bone marrow mesenchymal stem cells co-cultured with mature endothelial membrane showed a microenvironment dependent capacity for differentiating to endothelium, with the morphological changes revealed starting from the 2nd week, showing cell body contraction, polygonal-shaped change; and at the 3rd week, the markedly speedily cell proliferation with elliptic or slabstone-like change of cells. High levels of classic endothelial cell markers, such as mRNA expressions of CD31, vWF, VE-cadherin, and protein expressions of CD31 and VCAM1, were shown; the typical weibel-palade body of endothelial cell was found in the differentiated cells. Moreover, percentage of CD31 expression in the differentiated hMSCs was increased after Rg1 treatment dose-dependently., Conclusion: Under the microenvironment of co-culture, hMSCs could differentiate into cells presenting the characteristics of endothelial cell in aspects of the morphology and ultrastructure of cells, as well as the gene and protein expressions of cell markers; ginsenoside Rg1 can promote the microenvironment dependent differentiation of hMSCs to VECs system in vitro.

The effects of ketamine on transient outward potassium current (I(to)) of isolated human atrial myocytes were investigated to understand the mechanism of part of its effects by whole-cell patch-clamp. Atrial myocytes were enzymatically isolated from specimens of human atrial appendage obtained from patients under going cardiac valve displacing. Ito is recorded in voltage-clamp modes using the patch-clamp technique at room temperature. Currents signals were recorded by an Axopatch 200B amplifier with the Digidata 1322A-pClamp 9.0 data acquisition system. Ketamine decreased I(to) of human atrial myocytes in a dose-dependent manner. The current-voltage curve was significantly lowered, 30, 100, 300, and 1000 micromol x L(-1) ketamine decreased respectively I(to) current density about (13.62 +/- 0.04)%, (38.92 +/- 0.05)%, (72.24 +/- 0.10)% and (83.84 +/- 0.05)% at the potential of 50 mV, with an IC50 of 121 micromol x L(-1). The I(to) activation curve, inactivation curve and the recovery curve were not altered by ketamine. So, ketamine concentration-dependently decreased I(to) of human atrial myocytes.

Objective: To study the effect of high glucose on GRK2 gene expression in H9C2 cardiomyoblasts in vitro., Methods: H9C2 cardiomyoblasts were cultured for 72 h in the presence of 0, 5.5, 12.5, 25 or 33 mmol/L glucose (with the osmotic pressure adjusted with monnitol). Semi-quantitative detection of GRK2 gene expression in H9C2 cardiomyoblasts was carried out using RT-PCR and phosph-Akt (Ser473) protein level was measured by Western blotting., Results: Glucose in the culture medium (5.5 to 33 mmol/L) concentration-dependently increased the mRNA expression of GRK2 concentration and decreased phosphorylation Akt (ser473) level in in H9C2 cardiomyoblasts., Conclusion: Increased GRK2 gene expression may play an important role in cardiac dysfunction in diabetes.

C-kit-positive neonatal cardiomyocytes (NCMs) contribute to myocardial regeneration. However, the myocardium itself cannot give rise to a robust regenerative response owing to the limited numbers of c-kit-positive resident stem cells present in the heart. It has been shown that mesenchymal stem cells (MSCs) can enhance cardiac repair via the release of paracrine factors such as insulin-like growth factor (IGF-1). We investigated whether the increased expression of c-kit in NCMs mediates the beneficial effects of MSCs on cardiac repair. MSCs and NCMs were prepared from Lewis rats and co-cultured in a Transwell system, which allowed the diffusion of secreted factors but prevented cell contact between the two cell types. The proliferation of NCMs was determined by BrdU assay. The expression of c-kit was assessed by real-time PCR and flow cytometry. The apoptosis rate of NCMs in response to hypoxia was determined by flow cytometry. We found that the expression of c-kit in NCMs was increased by paracrine factors released by MSCs. The effect of paracrine factors on c-kit expression was attenuated by IGF-1 receptor-neutralizing antibody. Furthermore, we found that increased c-kit expression requires IGF-1 receptor activation via the phosphatidylinositol 3 kinase/Akt-mediated pathway. These findings provide a new paradigm for the biological effects of IGF-1 and have significant implications for understanding the beneficial effects of MSCs on myocardial regeneration.

Objective: To investigate the interaction domains between macrophage migration inhibitory factors (MIF) and the extracellular segment of type-II trans-membrane protein CD74 using a yeast two-hybrid system., Methods: By using molecular cloning techniques, the DNA fragments encoding MIF, MIF(50-65) and MIF(1-50/65-115) were introduced into the pGBKT7 vector to construct the corresponding recombinant bait plasmids, and the DNA fragments encoding CD74(73-232), CD74(73-109), CD74(1109-149) and CD74(149-232) into the pGADT7 vector to construct the recombinant activation domain (AD) plasmids. PEG/LiAC method was employed to transform the above 3 recombinant bait plasmids paired with each of the 4 recombinant AD plasmids into the chemical competent yeast AH109 cells. The transformed yeast AH109 cells were screened consecutively on SD/-Trp-Leu and SD/-Trp-Leu-Ade-His/X-alpha-gal nutritional media., Results: The results of restriction endonuclease digestion and DNA sequencing verified the correct construction of all the recombinant plasmids. The yeast AH109 cells transformed with each of the 3 recombinant bait plasmids could grow on SD/-trp nutritional media without autonomous activation effect on the reporter gene MEL1. The cells transformed with each of the 4 recombinant AD plasmids could also grow on SD/-leu nutritional media without activation of the reporter gene MEL1. Only the yeast AH109 cells co-transformed with MIF, MIF(50-65), or MIF(1-50/65-115) plasmid and CD74(73-232) plasmid could grow on SD/-Trp-Leu-Ade-His nutritional media with transcription activation of the reporter gene MEL1., Conclusion: MIF interacts with the intact extracellular segment of CD74 (CD74(73-232)) independent of the functional domain of MIF(50-65).

The purpose of this study was to investigate the influence of nitro oxide (NO) from mesenchymal stem cells (MSC) on the proliferative responses of allogeneic lymphocytes and its mechanism. MSCs were isolated and cultured from human bone marrow. Selected surface antigens of MSCs were detected by flow cytometry and their morphologic characteristics were determined by microscopy. Mitomycin C-treated MSCs were plated in dishes and then mixed lymphocyte cultures (MLC) were set up. After 4 days, lymphocyte proliferation was determined by CCK-8 assays; NO secretion in coculture supernatant was determined by Griess reagent kit; the level of FOXP3 mRNA expression was detected by real-time quantitative PCR. The results indicated that in MSC/MLC coculture experiment, the lymphocyte proliferation decreased significantly with of IOD value 0.49+/-0.03, NO production increased obviously (21.05+/-1.14 micromol/L) and FOXP3 mRNA expression was increased [(1.56+/-0.34)%] as compared with MLC coculture without MSC. There were significant difference between these two groups. It is concluded that NO production in human MSC culture up-regulates FOXP3 mRNA expression and thus inhibits lymphocyte proliferation response.

Objective: To establish an efficient method for screening effective small interference RNA (siRNA) using dual-luciferase reporter assay system., Methods: Based on the siRNA expression vector pSilencer-4.1, 3 candidate green fluorescence protein (GFP) gene siRNA expression plasmids, namely pSi-GFPsiRNA1, pSi-GFPsiRNA2, and pSi-GFPsiRNA3, along with the negative control pSi-Negative, were constructed. Using the pGL3-promoter vector, the GFP-luciferase (GFP-LUC) expression plasmid pGL3-GFPf was constructed with the same Kozak consensus translation initiation site and start codon ATG for GFP-LUC coding sequence. The GFP fragment containing the target sequences of 3 GFP siRNAs was introduced into the 3' untranslate region of LUC in the modified pGL3-promoter vector to construct the plasmid pGL3-GFPp. The GFP siRNAs expression plasmids and Renilla luciferase reporter vector pRL-TK were co-transfected with pGL3-GFPf or pGL3-GFPp into the HEK293 cells, respectively. The luciferase activities were determined by dual-luciferase reporter assay, and the GFP mRNA expressions were detected by real-time quantitative PCR., Results: In the groups cotransfected with GFP siRNAs expression plasmids and pGL3-GFPf, the luciferase activities were reduced obviously, and the reduction was more significant in cells transfected with GFPsiRNA1 compared with the control cells (P<0.01).GFP mRNA levels were also markedly lowered in cells transfected with GFPsiRNA1 as shown by real-time PCR (P<0.01). In addition, the results of dual-luciferase reporter assay and real-time PCR showed that among the groups cotransfected with GFP siRNAs expression plasmids and pGL3-GFPp, the GFP expression was inhibited most obviously by GFPsiRNA1 (P<0.01)., Conclusion: The dual-luciferase reporter assay system provides a useful method for screening effective siRNAs targeting specific genes.

Objective: To compare the efficacy of transplanting bone marrow mesenchymal stem cell (BMSC) or microenvironmental induced BMSC (iBMSC) into the ischemic myocardium of rats with myocardial infarction., Methods: iBMSC was defined as BMSC co-cultured with myocardial cells for 2 weeks. The stem cells or equal volume PBS were injected into ischemic border zone 1 wk after experimental infarction. Cardiac performance was evaluated at 1, 2, and 4 wk after cell transplantation by echocardiography and analyzed histologically at 4 wk after cell transplantations., Results: Compared with PBS group, both BMSC and iBMSC transplantations reduced infarct size. iBMSC enhanced the beneficial effects of BMSC on improving cardiac function (FS: 28.5% +/- 4.3% in PBS, 29.0% +/- 2.0% in BMSC and 45.1% +/- 3.1% in iBMSC group at 4 weeks post transplantation, iBMSC group vs. PBS group P < 0.05, iBMSC group vs. BMSC group P < 0.05). Immunofluorescence microscopy results revealed co-localization of SPIO-labeled transplanted cells with cardiac markers for cardiomyocytes, indicating regeneration of damaged myocardium., Conclusion: Our data suggest that iBMSC implantation is more effective on improving cardiac function than BMSC implantation in this model. iBMSC might serve as a new promising therapeutic cell source for regenerating ischemic myocardium in patients with post-infarction heart failure.

Objective: To explore VEGF siRNA's effect on the immature fetal retinal microvascular endothelial cells in vitro., Method: The fresh retinal micrangium was primarily cultured to obtain microvascular endothelial cells. CoCl2 was used to simulate oxygen-deficient conditions. siRNA directed against human VEGF was designed and chemically synthesized. There were 3 groups in our experiment: VEGF siRNA group, hypoxia control group, and negative siRNA control group. The fetal retinal micrangium vascular endothelial cells were transfected by using liposome. The expression levels of VEGF mRNA and protein were evaluated by RT-PCR and Western blotting 24, 48, 72 h after transfection, cell proliferation was evaluated by MTT method., Result: The expression levels of VEGF mRNA decreased by 21.05%, 79.67%, and 90.48% 24 h, 48 h, and 72 h after transfection as compared to those in hypoxia control group, the expression level of VEGF protein had decreased by 14.58%, 66.97%, and 81.61% as compared to those in hypoxia control group. The siRNA could decrease cell proliferation under hypoxia too, the multiplication rate after 12, 24, 48, and 72 h decreased by 15.0%, 42.9%, 78.3% and 65.9%., Conclusion: VEGF siRNA could down-regulate the expression of VEGF in immature fetal retinal microvascular endothelial cells and suppressed cell proliferation. Application of siRNA to inhibit expression of VEGF may be a hopeful way to prevent and cure ROP.

Objective: To establish a rat model of full-thickness skin defect to receive bone marrow mesenchymal stem cell transplantation for wound repair., Methods: A full-thickness skin defect measuring 4 cmx4 cm in 36 F344 rats, which were divided into 3 groups with the wound covered with alloskin graft, acellular dermal matrix, or petrolatum gauze. In vitro cultured BMSCs in the 5th passage were transplanted into the skin defect, and the time of wound dressing dissociation and number of transplanted Brdu-positive cells in the wound were observed 14 days later., Results: The alloskin graft resulted in significantly longer time before dressing dissociation, with greater number of Brdu-positive cells in the wound than the other two wound dressings (P<0.001). The acellular dermal matrix showed better effect than petrolatum gauze in terms of the dressing dissociation time and the viable transplanted cell number in the wound., Conclusion: Alloskin graft can be ideal for covering the wound surface to protect the transplanted BMSCs in rats.

Objectives: To depict the interaction between atrial fibrillation (AF) and inflammatory reaction, studies were taken to measure the activity of NF-kappaB in myocardium, the concentration of regional inflammatory factors and the pathological process of the right atrium in patients with AF., Design: Patients with valvular disease with AF or sinus rhythm (SR) were recruited and compared. Before the extracorporal circulation, about 250 mg tissue of right atrium was collected for pathological examination. The activity of NF-kappaB in myocardium was measured by electrophoretic mobility shift assay (EMSA), and the concentration of cardiac tissue interleukin-6 (IL-6) and tumor necrosis factor (TNF-alpha) was determined by radioimmuoassay., Results: Patients with valvular disease with AF exhibited higher NF-kappaB activity, higher concentration of TNF-alpha and IL-6, severe lymphomonocyte infiltration, and more fibrosis than those patients with valvular disease with SR. There were significant positive correlations among NF-kappaB activity and levels of TNF-alpha and IL-6 and collagen volume fraction., Conclusions: This study proved the presence of inflammation in atrial myocardium by triggering inflammatory reaction.

Objective: To construct an eukaryotic expression vector for miRNA-1-2 that can be expressed in rat H9C2 cardiomyocytes., Methods: The precursor miRNA (pre-miRNA) DNA template for miRNA-1-2 was designed and generated by PCR amplification. The DNA template was inserted into the hairpin RNA expression vector pSilence-4.1-neo and identified by DNA sequencing analysis. The recombinant plasmid DNA was then transfected into H9C2 cells via Lipofectamine, and the green fluorescence protein expression vector pEGFP-N3 served as the transfection marker. Twenty-four hours after transfection, the total cellular RNA was extracted using TRIzol reagent, and thermoscript reverse transcriptase (RT)-PCR was performed to determine miRNA-1-2 precursor expression., Results and Conclusion: DNA sequencing indicated that the miR-1-2 expression plasmid was correctly constructed. The precursor miRNA-1-2 was successfully expressed in the H9C2 cells, and the expression of Hand2 protein could be efficiently inhibited by miRNA-1.

Objective: To investigate the ability of human bone marrow mesenchymal stem cells (hBMSCs), cocultured with semi-permeable membrane separated neonatal rat ventricular myocytes, to differentiate into cardiomyocytes., Methods: hBMSCs were isolated and purified by density gradient centrifugation and adherence screening method. Cells were expanded as undifferentiated cells in culture for more than 3 passages and their phenotypes were identified with flow cytometer. hBMSCs were cocultured with neonatal rat ventricular myocytes in a rate of 1:10 separated by semi-permeable membrane. GATA4 mRNA was detected by RT-PCR; Immunocytochemistry, and Immunostaining were used to detect sarcomeric alpha-actinin, desmin, cTnT, and cTnI protein level., Results: CD29 (98.64% +/- 0.80%) and CD44 (96.70% +/- 1.50%) were the major surface markers of hBMSCs. After coculturing with semi-permeable membrane separated neonatal rat ventricular myocytes, the first contraction of single cells was noted at day 7 and GATA4 expression was detected on these cells by RT-PCR after 1 to 3 weeks coculture. Desmin, sarcomeric alpha-actinin, cTnI and cTnT could be detected by immunocytochemistry and immunostaining on some of these cells., Conclusion: hBMSCs possess the potential to differentiate into myocardial cell phenotype in the cardiac microenvironment. Direct contact with cardiomyocytes was not necessary required for hBMSCs differentiation.

Objective: To investigate the effect of adenoviral vector infection on the differentiation potential of human bone marrow mesenchymal stem cells (hMSCs)., Methods: The third-passage hMSCs were infected with the recombinant adenovirus expressing green fluorescence protein (GFP) for 2, 4, 8 and 16 days. RT-PCR was used to detect the mRNA expression of endodermal marker CYP 51, mesodermal marker SM22alpha, ectodermal marker nestin, pluripotent marker oct-4 and the alternative splicing factor nPTB. Seven days after adenovirus infection, the hMSCs were cultured in the presence of adipogenic agents for 14 days, and the adipose cells differentiated from hMSCs were detected with oil red O staining., Results: Compared with normal hMSCs, the cell infected with the adenovirus for 2, 4, 8 and 16 days showed no obvious down-regulation of CYP51, SM22alpha, nestin, OCT4 or nPTB. The hMSCs 7 days after adenovirus infection were induced to differentiate into adipose cells, with a similar differentiation rate to that of normal hMSCs. CONCLUSION The differentiation potential of hMSCs is not affected by adenovirus infection, suggesting that adenovirus can be used as the gene delivery vector in MSC differentiation studies.

Objective: To investigate the expression of representative heart-specific primary microRNAs (pri-miRNAs) in the cardiomyocyte-like cells differentiated from human mesenchymal stem cells (hMSCs)., Methods: The phenotype of hMSCs isolated was identified by flow cytometry using monoclonal antibodies against FITC-conjugated CD29, CD34, and CD11b. The third-passage hMSCs were induced to differentiate into cardiomyocyte-like cells by 5-azacytidine and indirect coculture with neonatal rat myocytes, respectively. Immunocytochemical analysis was performed to detect the expression of the cardiac-specific proteins, namely cardiac troponin I (cTnI) and sarcomeric alpha-actinin, in the cardiomyocyte-like cells differentiated from hMSCs. RT-PCR and DNA sequencing were used to identify the expression of the 5 representative heart-specific pri-miRNAs., Results: High hMSC marker CD29 expression rate (98.87%) and low hematopoietic cell markers CD34 (5%) and CD11b (0.4%) expression rates were identified in the hMSCs isolated. cTnI and sarcomeric alpha-actinin expression occurred in the hMSCs following induction with the 2 differentiation-inducing methods. miRNA-143 and -181 expressions were induced in the hMSCs by 5-azacytidine and miRNA-143, -181, -206, and -208 expressions were induced by indirect coculture with neonatal rat myocytes, but pri-miRNA-1-2 expression failed to be induced by these two induction methods., Conclusion: Expressions of the representative heart-specific pri-miRNAs in different patterns can be induced in cardiomyocyte-like cells differentiated from hMSCs by 5-azacytidine and indirect coculture with neonatal rat myocytes.

The objective of this study was to analyze the level of bcr-abl mRNA in peripheral blood (PB) after allogeneic stem cell transplantation (allo-SCT) in chronic myeloid leukemia patients, providing a experimental basis for diagnosing early relapse. bcr-abl mRNA levels in 78 PB and bone marrow (BM) samples from 15 CML patients after allo-SCT were detected by using real-time quantitative PCR. The results indicated that levels of bcr-abl mRNA before transplantation were high (median 29.303%) and decreased greatly (median 0) at the first month after allo-SCT. During the first year after allo-SCT, the patterns of serial bcr-abl transcripts varied in number, but the overall bcr-abl transcript levels significantly decreased at 6 months after allo-SCT. Majority of patients with undetectable or very low levels of bcr-abl mRNA were monitored after 1 year following transplantation. The hematological features of BM and PB in all detected patients remained normal. PB and BM bcr-abl values were not different significantly and had the similar trend of changes. It is concluded that the bcr-abl mRNA levels in CML patients change greatly early after allograft. Serial monitoring measurements for bcr-abl mRNA contribute to understanding the trend of change and effect of transplantation, also can be a guidance for starting therapy. But detectable levels of bcr-abl mRNA during the first 6 months do not indicate relapse. Measurements of bcr-abl mRNA of PB may be more suitable for routine monitoring long-term disease status in CML after allo-HSCT.

Objective: To develop an effective method for screening recombinant hairpin RNA expression plasmids using single restriction endonuclease analysis., Methods: The double-strand DNA fragment containing a ClaI site (the flanking sequences of which were not complementary) was annealed and ligated into small hairpin RNA (shRNA) expression vector pSilencer-4.1 that did not contain ClaI site to construct the circular pSilencer-4.1-ClaI vector. With BamHI and HindIII, the pSilencer-4.1-ClaIwas digested and ligated with the DNA template of green fluorescence protein (GFP) shRNA that did not include a ClaI site. The plasmid DNA of the positive clones was extracted and digested with ClaI, and the inserted DNA sequence of the non-linearized plasmid was identified by sequence analysis., Result and Conclusion: DNA sequencing showed that pSilencer-4.1-ClaI was correctly constructed and the plasmids resistant to ClaI digestion were all recombinant vectors encoding GFP shRNA. The constructed pSilencer-4.1-ClaI can be used as a universal vector to construct the shRNA expression plasmid, and the incorporated ClaI sites may allow efficient screening of recombinant shRNA expression vectors.

Peripheral circulating lymphocytes are easily accessible cells for investigating changes in beta-adrenergic receptors (ADRBs) in humans, but previous reports indicate that these cells only express ADRB2. This study aimed to investigate whether ADRB1 and ADRB3 were expressed in peripheral lymphocytes and the changes of ADRBs in congestive heart failure. Our study demonstrates that ADRB1, ADRB2, and ADRB3 coexist in human peripheral lymphocytes, with differential binding property and expression level. Patients with congestive heart failure had significantly decreased total ADRB density and mRNA levels of ADRB1 and ADRB2 genes, but not ADRB3, compared with healthy subjects. The levels of mRNA of ADRB1 and ADRB2 in peripheral lymphocytes from patients with congestive heart disease were significantly increased after drug treatment. Our study, for the first time, indicates that human peripheral lymphocytes coexpress ADRB1, ADRB2, and ADRB3, which has important implications for precisely predicting clinical response to drug therapy in congestive heart failure.

Objective: Inflammation is involved in the process of coronary heart disease (CHD). Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine which can inhibit the random migration of macrophages and concentrate macrophages at the inflammatory site, and is thought to play an important role in cell mediated immunity. The present study is to investigate the association of the -173 G/C polymorphism of MIF gene with the outcome of the CHD., Methods: One hundred and thirty-eight patients with coronary angiography (CAG) proved CHD were studied, and 163 healthy matched controls in Guangdong were studied. Patients and controls were genotyped for a single nucleotide polymorphism in the 5'-flanking region at position -173 of the MIF gene, using PCR-RFLP analysis, followed by DNA sequencing identification., Results: Only MIF -173G/G and MIF -173G/C genotypes were detected in CHD patients and controls. The MIF -173 G allele was detected in 0.966 of normal controls and 0.917 of patients, while MIF -173 C allele was detected in 0.034 of normal controls and 0.083 of patients. Individuals possessing a MIF-173*C genotype have an increased risk of CHD (16.7% versus 6.8%) (OR: 2.764, 95% CI: 1.295-5.899; P= 0.007)., Conclusion: These results suggest that MIF -173G /C polymorphism was associated with CHD in Chinese population, the MIF -173C allele might be a risk factor for CHD in Chinese Han nationality.

Objective: To investigate the association between macrophage migration inhibitory factor (MIF) and collagen synthesis in vascular smooth muscle cells (VSMCs)., Method: VSMCs isolated from SD rat aorta were cultured in different culture plates, and the fourth passage of cells were divided into two groups, one of which was simulated by MIF and the other served as control group. Collagen I and III mRNA expression in the VSMCs was detected by reverse transcriptase (RT)-PCR and PCR., Result: Collagen I and III mRNA expression in MIF-treated VSMCs increased significantly as compared with that in the control cells (P<0.05)., Conclusion: MIF increases collagen I and III mRNA expression of VSMCs in vitro, indicating its involvement in collagen synthesis in VSMCs.

Objective: To examine the level of plasma macrophage migration inhibitory factor (MIF) in patients with congestive heart failure (CHF) and its relationship with cardiac function., Method: The levels of MIF were measured in 278 CHF patients and 85 normal subjects using enzyme-linked immuno-sorbent assay (ELISA)., Results: Elevated MIF levels were detected in the patients with heart failure, and the elevation was more significant in cases of coronary artery disease in comparison with that identified in cases of dilated cardiomyopathy., Conclusion: The overactivation of MIF may be involved in the pathogenesis of heart failure.