[Long non-coding RNA in spermatogenesis regulation and male infertility: Progress in research].

Long non-coding RNA (lncRNA) is an RNA molecule transcribed by RNA polymerase II, longer than 200 nt, and not translated into proteins. During gonadal development and spermatogenesis, lncRNAs are involved in epigenetic mechanisms, including DNA methylation, chromatin remodeling, and histone tail modification, which play important regulatory roles at the transcriptional or post-transcriptional level. Epigenomics including lncRNA is considered to be the second dimension of DNA sequence that can be adapted to environmental factors to specifically regulate gene expressions in some cells. Based on the functional action mechanism of lncRNAs, we reviewed the advances in the studies of lncRNAs in the direction of spermatogenesis and male infertility and analyzed the potential of lncRNAs as a biomarker of male infertility. The potential application of lncRNA in the treatment of male infertility diseases can be further explored based on the lncRNA target, RNA interference, competitive binding closed target and structural disruption of lncRNAs.

Establishment of a chronic left ventricular aneurysm model in rabbit.

OBJECTIVES: To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm (LVA) in rabbits. METHODS: Acute myocardial infarction (AMI) was induced in 35 rabbits via concomitant ligation of the left anterior descending (LAD) coronary artery and the circumflex (Cx) branch at the middle portion. Development of AMI was confirmed by ST segment elevation and akinesis of the occluded area. Echocardiography, pathological evaluation, and agar intra-chamber casting were utilized to validate the formation of LVA four weeks after the surgery. Left ventricular end systolic pressure (LVESP) and diastolic pressure (LVEDP) were measured before, immediately after and four weeks after ligation. Dimensions of the ventricular chamber, thickness of the interventricular septum (IVS) and the left ventricular posterior wall (LVPW) left ventricular end diastolic volume (LVEDV), systolic volume (LVESV), and ejection fraction (EF) were recorded by echocardiogram. RESULTS: Thirty one (88.6%) rabbits survived myocardial infarction and 26 of them developed aneurysm (83.9%). The mean area of aneurysm was 33.4% ± 2.4% of the left ventricle. LVEF markedly decreased after LVA formation, whereas LVEDV, LVESV and the thickness of IVS as well as the dimension of ventricular chamber from apex to mitral valve annulus significantly increased. LVESP immediately dropped after ligation and recovered to a small extent after LVA formation. LVEDP progressively increased after ligation till LVA formation. Areas in the LV that underwent fibrosis included the apex, anterior wall and lateral wall but not IVS. Agar intra-chamber cast showed that the bulging of LV wall was prominent in the area of aneurysm. CONCLUSIONS: Ligation of LAD and Cx at the middle portion could induce development of LVA at a mean area ratio of 33.4% ± 2.4% which involves the apex, anterior wall and lateral wall of the left ventricle.

Combined treatment of ulinastatin and tranexamic acid provides beneficial effects by inhibiting inflammatory and fibrinolytic response in patients undergoing heart valve replacement surgery.

OBJECTIVE: To investigate the effect of ulinastatin and tranexamic acid administered alone or in combination on inflammatory cytokines and fibrinolytic system in patients undergoing heart valve replacement surgery during cardiopulmonary bypass (CPB). BACKGROUND: CPB-induced fibrinolytic hyperfunction and systemic inflammatory response syndrome (SIRS) are the leading causes responsible for the occurrence of postsurgical complications such as postsurgical cardiac insufficiency and lung injury, which may lead to an increase in postsurgical bleeding, prolongation of hospital stay, and increased costs. METHODS: One hundred twenty patients undergoing heart valve replacement surgery during CPB were randomly assigned into 4 groups of 30 patients each: blank control group (Group C), tranexamic acid group (Group T), ulinastatin group (Group U), and tranexamic acid-ulinastatin combination group (Group D). Physiological saline, tranexamic acid, ulinastatin, and a combination of tranexamic acid and ulinastatin were given to each group, respectively. Arterial blood was collected from the radial artery at 4 time points: after induction of anesthesia (T1), unclamping the ascending aorta (T2), and at 1 hour (T3) and 24 hours (T4) after CPB. The levels of plasma tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), neutrophil elastase (NE), and the concentrations of tissue plasminogen activator (t-PA) and α2-antiplasmin (α2-AP) were detected. The changes in the volume of pericardial mediastinal drainage after surgery were observed and recorded. RESULTS: The plasma TNF-α, IL-6, and NE levels significantly increased in patients from all 4 groups at time points of T2, T3, and T4 in comparison to those before CPB (P < .05), and the plasma TNF-α and IL-6 levels in groups U and D were significantly lower than those in the other 2 groups (P < .05). The plasma t-PA, α2-AP, and D-dimer concentrations significantly increased in patients from all 4 groups at T2 and T3 compared with those before CPB (P < .05), and the plasma t-PA and D-dimer concentrations were significantly lower in groups T and D than those in groups U and C (P < .05) at T2 and T3. The plasma α2-AP concentrations in groups T and D were significantly higher than those in Group C at T3 (P < .05). The volumes of pericardial mediastinal drainage per body surface area were significantly lower in groups T and D than those in Group C 6 hours after the surgery (P < .05). CONCLUSIONS: Ulinastatin inhibits the release of inflammatory medium and reduces the inflammatory response during CPB. Tranexamic acid can effectively inhibit the fibrinolytic hyperfunction caused by CPB and thus decreases postsurgical bleeding. In addition, it exhibits a minor anti-inflammatory response. As a consequence, a combined treatment of ulinastatin and tranexamic acid reduces postsurgical bleeding and shortens postoperative hospital stay in patients undergoing heart valve replacement surgery.

[Inhibitory effect of fluvastatin on lysophosphatidylcholine-induced ventricular arrhythmias in rats].

OBJECTIVE: To investigate the effect of fluvastatin on lysophosphatidylcholine (LPC)-induced ventricular arrhythmias and its mechanism. METHODS: Twenty male SD rats were randomly allocated into two equal groups, namely LPC treatment group and fluvastatin pretreatment group. Langendorff apparatus was used for cardiac perfusion ex vivo with 5 µmol/L LPC for 5 min followed by washing for 30 min in LPC treatment group, and in fluvastatin pretreatment group, a 30-min perfusion with 10 µmol/L fluvastatin was administered before LPC perfusion. The LPC-induced nonselective cation current (I(NSC)) in the ventricular myocytes was recorded using the whole-cell voltage-clamp method. RESULTS: Fluvastatin significantly inhibited LPC-induced ventricular tachyarrhythmia/fibrillation and I(NSC). The small G-protein Rho inhibitor (C3) and Rho-kinase inhibitor (Y-27632) in the pipette solution also suppressed LPC-induced I(NSC). CONCLUSION: Fluvastatin offers cardiac protection against LPC by inhibiting LPC-induced I(NSC). LPC induces fatal arrhythmia via a Rho/Rho-kinase-mediated pathway.

[Establishment of a rabbit model of congestive heart failure].

OBJECTIVE: To study the feasibility of establishing a rabbit model of congestive heart failure model by abdominal aortic coarctation combined with intravenous epinephrine infusion. METHODS: Twenty rabbits were randomized into the study group (n=10) and control group (n=10). Congestive heart failure was induced in the study group by abdominal aortic coarctation combined with intravenous epinephrine infusion. The diameter of the abdominal aorta was reduced by 50%-60%, and epinephrine was infused at 2 weeks (5 mg.kg(-1).min(-1) for 60 min), 4 weeks (4 mg.kg(-1).min(-1) for 60 min) and 6 weeks (4 mg.kg(-1).min(-1) for 60 min) after the operation. The changes in the systolic and diastolic functions of the rabbits were assessed by echocardiography and catheterization during the progression of left hypertrophy. RESULTS: The diameter of the abdominal aorta at the coarctation region was 4.87-/+0.53 mm before the operation, reduced to 2.26-/+0.47 mm after the operation. At 8 weeks after the operation, the hearts of the rabbits in the study group showed obvious abnormalities in echocardiography, while the hearts in the control group remained normal. CONCLUSION: Abdominal aortic coarctation combined with intravenous epinephrine infusion allows rapid establishment of a reliable rabbit model of chronic congestive heart failure.

[The empirical study on paracrine communication of bone marrow mesenchymal stem cells].

OBJECTIVE: To study the influence of (60)Co gamma exposure on paracrine effect of marrow mesenchymal stem cells (MSC). To evaluate the function and construction after early stage of acute myocardial infarction (AMI) by injection of supernatant liquid. To discuss the mechanism of prarcrine communication initially. METHODS: MSC were radiated by (60)Co gamma with different dosage. The culture solution was collected peri-irradiation. The changes of Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), Interleuki-1beta (IL-1beta) in supernatant liquid were checked by ELISA. Using a rat model of AMI, the supernatant liquid and control medium were injected intramyocardially and intraperitoneally according to the project. After 4 weeks, the cardiac dimension and functions were assessed, the microvessel density were detected. RESULTS: Three cytokines decreased significantly after irradiation, with the increasing in dosage of irradiation, the secretory volume of cytokines decreased greatly. When compared with the control group (group A 6.6 +/- 0.6) and medium group (group C 5.7 +/- 0.7), the microvessel density in supernatant liquid group (group B 10.8 +/- 2.9) increased obviously, contributing to improvement in cardiac function and dimension. (Left ventricular internal dimension in diastolic (LVDd) postoperation: A 8.1 mm +/- 1.5 mm, B 7.0 mm +/- 1.5 mm, C 7.7 mm +/- 1.1 mm; Eject fraction (EF) postoperation: A 43.8% +/- 8.9%, B 51.5% +/- 7.8%, C 45.6% +/- 8.1%. CONCLUSIONS: (60)Co gamma radiation exposure can degrade MSC' ability of paracrine communication. The paracrine effect which should take important role in improving the cardiac function after AMI. The mechanism of prarcrine is complex, neovascularization is the important link.

[Study of the three-dimensional structure of the ventricular myocardial fiber in human heart].

OBJECTIVE: To study the three-dimensional structure of ventricular myocardial fiber in human heart. METHODS: Eight human heart were obtained from male donors aged 81.9-/+7.2 years with a heart weight of 455.6-/+65.7 g. Each sample was immersed in water and scanned by diffusion tensor magnetic resonance imaging (DT-MRI) using a 3 Tesla Exicte HD by an eight-channel head coils. The duration was 18.6-/+5.2 h from heart arresting to the scanning. The data were obtained using the protocol of single shot echo planar imaging (sshEPI) and sensitivity encoding (SENSE). The SENSE-sshEPI-scans (TE/TRZ86.4/2000 ms) of the whole heart were carried out (b=1000 s/mm(2), voxels 128x128, resolution 1.1 mmx1.1 mmx(3) mm, and FOV 14 cmx14 cm). Fiber tracking and reconstruction were performed using GE Advantage Windows Workstation. The three-dimensional structure of the ventricular myocardial fiber was observed. RESULTS: The left ventricular myocardial fibers showed two layers with different directions of alignment in such regions as the anterior, septum, and posterior walls and the free left ventricular wall. The subendocardial layer ran obliquely from the base to the apex, and the middle layer ran obliquely upward from the base to the apex. The two layers were linked together and aligned in the pattern of helical coils near the apex. CONCLUSIONS: The three-dimensional structure of the myocardial fibers in human heart conforms to Torrent's hypothesis of helical ventricular myocardial band (HVMB).

Sevoflurane postconditioning protects isolated rat hearts against ischemia-reperfusion injury: the role of radical oxygen species, extracellular signal-related kinases 1/2 and mitochondrial permeability transition pore.

The roles of reactive oxygen species (ROS), extracellular signal-regulated kinase 1/2 (ERK 1/2) and mitochondrial permeability transition pore (mPTP) in sevoflurane postconditioning induced cardioprotection against ischemia-reperfusion injury in Langendorff rat hearts were investigated. When compared with the unprotected hearts subjected to 30 min of ischemia followed by 1 h of reperfusion, exposure of 3% sevoflurane during the first 15 min of reperfusion significantly improved functional recovery, decreased infarct size, reduced lactate dehydrogenase and creatine kinase-MB release, and reduced myocardial malondialdehyde production. However, these protective effects were abolished in the presence of either ROS scavenger N-acetylcysteine or ERK 1/2 inhibitor PD98059, and accompanied by prevention of ERK 1/2 phosphorylation and elimination of inhibitory effect on mPTP opening. These findings suggested that sevoflurane postconditioning protected isolated rat hearts against ischemia-reperfusion injury via the recruitment of the ROS-ERK 1/2-mPTP signaling cascade.

[Effects of pravastatin and granulocyto-colony stimulating factor in mobilizing endothelial progenitor cells in mice with myocardial ischemia].

OBJECTIVE: To compare the effects of pravastatin and granulocyto-colony stimulating factor (G-CSF) in mobilizing endothelial progenitor cells (EPCs) in mice with myocardial ischemia, and explore the possible mechanism of EPC mobilization. METHODS: Ninety-six mice were randomly divided into 4 groups (n=24), namely the control group, saline group, pravastatin group and G-CSF group. In the latter 3 groups, myocardial ischemia was induced with isoprenine followed by intraperitoneal injections of normal saline, pravastatin and G-CSF for 5 consecutive days. On days 1, 5, 7, and 9 after establishment of myocardial ischemia, 6 mice from each group were randomly selected for measurement of the EPC count and serum concentrations of vascular endothelial growth factor (VEGF). RESULTS: Compared with the control group, EPC count increased slightly in the saline group on days 1, 5, and 7. EPC count increased significantly in pravastatin group on days 5, 7 and 9 in comparison with that of the saline group, and the increment was more obvious in G-CSF group. In comparison with the control group, the concentrations of VEGF augmented on days 5, 7 and 9 in the order of saline group, pravastatin group and G-CSF group. The effect of G-CSF on EPC mobilization was positively correlated to VEGF concentrations. CONCLUSION: Myocardial ischemia induces EPC mobilization and VEGF release. Both Pravastatin and G-CSF can enhance EPC mobilization from the bone marrow and VEGF release, but G-CSF produces a stronger effect on EPC mobilization in association of VEGF release.

Effect of subzero-balanced ultrafiltration on postoperative outcome of patients after cardiopulmonary bypass.

OBJECTIVE: To evaluate the effect of a new ultrafiltration technique - subzero-balanced ultrafiltration technique - on early postoperative outcomes of adult patients undergoing cardiac operations with cardiopulmonary bypass. METHODS: A total of 120 patients who required cardiopulmonary bypass for cardiac surgery were randomized into two groups, 60 in each group. Patients in the treatment group received subzero-balanced ultrafiltration during cardiopulmonary bypass, while patients in the control group received routine cardiopulmonary bypass. Postoperative outcomes, including hospital mortality and morbidity of the two groups, were analyzed. RESULTS: Hospital mortality was 0% (0 of 60) in the treatment group versus 1.8% (1 of 60) in the control group (P=1.000). Total hospital complications was lower in the treated patients (11 of 60 [18.3%] versus 22 of 60 [36.7%], P=0.025). Duration of intubation time was shorter and transfusion volume within 24 hours postoperatively was less in patients having received subzero-balanced ultrafiltration during cardiopulmonary bypass (14.35 + or - 1.66 versus 18.64 + or - 1.57 h, P=0.036 and 1.54 + or - 1.56 versus 3.64 + or - 2.67 U/patient, P=0.032). Length of stay on the intensive care unit, duration of hospital stay, need for infusion of inotropic agent and drainage volumes within 24 h postoperatively between the two groups were comparable. CONCLUSIONS: Subzero-balanced ultrafiltration during cardiopulmonary bypass can effectively decrease the patients' hospital morbidity and the volume of blood transfusion: it also may promote early postoperative recovery of patients. Routine application of subzero-balanced ultrafiltration during adult cardiac operations should not be necessary, but the technique should be compared to other techniques, e.g. MUF, in further studies.

Adenoviral gene transfer of sphingosine kinase 1 protects heart against ischemia/reperfusion-induced injury and attenuates its postischemic failure.

Sphingosine kinase 1 (SPK1) has been identified as a central mediator of ischemia preconditioning and plays a protective role in ischemia/reperfusion (I/R)-induced cardiomyocyte death. In the present study, we investigated the protective effect of adenovirus-mediated SPK1 gene (Ad-SPK1) transfer on I/R-induced cardiac injury, and evaluated its therapeutic action on postinfarction heart failure. Cardiac SPK1 activity was increased about 5-fold by injection of Ad-SPK1, compared with injection of adenovirus carrying the green fluorescent protein gene (Ad-GFP). A more potent performance and a lower incidence of arrhythmia were observed in Ad-SPK1-injected hearts during the reperfusion period, compared with Ad-GFP-injected hearts. An enzymatic activity assay showed that creatine kinase release was also less in Ad-SPK1-injected hearts. To investigate the therapeutic action of the SPK1 gene on postischemic heart failure, the left anterior descending branch of the coronary artery in Wistar rats was ligated after direct intramyocardial injection of Ad-SPK1 or Ad-GFP as a control. Ad-SPK1 injection significantly preserved cardiac systolic and diastolic function, as evidenced by left ventricular (LV) systolic pressure, LV end-diastolic pressure, and peak velocity of contraction (dP/dt). The LV morphometric parameters of Ad-SPK1-treated animals were also preserved. In addition, SPK1 gene delivery significantly enhanced angiogenesis and reduced fibrosis. These results demonstrate that adenovirus-mediated SPK1 gene transfer could efficiently prevent I/R-induced myocardial injury and attenuate postischemic heart failure. Thus, SPK1 gene delivery would be a novel strategy for the treatment of coronary heart disease.

[The experimental studies on cell transplantation into chronic ischemic myocardium using mesenchymal stem cells modified by recombinant adenovirus carrying vascular endothelial growth factors 165 gene].

OBJECTIVE: To observe the therapeutic effect of vascular endothelial growth factors 165 (VEGF165) gene expressing mesenchymal stem cells (MSCs) in chronic myocardial infarction model by providing enhanced cardioprotection, followed by angiogenic effects in infarcted myocardium. METHODS: Recombinant adenovirus vector carrying VEGF165 gene (rAd-VFGF165) was constructed. MSCs were harvested through gradient centrifugation, then were cultivated, multiplied and expanded. Recombinant adenoviruses mediated VEGF165 gene were transfected into MSCs, and the MSCs were labelled by DAPI. The left anterior descending branch of rabbits were ligated to establish a myocardial infarction model; and the animals survived for 6 weeks were randomly divided into three groups: VEGF165-expressing MSCs transplanted (Group I), MSCs transplanted (Group II) and dulbecco modified eagles medium injected (Group III). At 4 weeks after cell transplantation, the MSCs were detected by DAPI staining in infarcted region. The cardiac functions were estimated by UCG. The microvascular density in infarcted area were estimated through CD34 immunohistochemical analysis. RESULTS: Four weeks after cell transplantation, ejection fraction, E wave/A wave ratio and capillary density of the infarcted region were most improved in Group I compared with Group II and control group (P < 0.05). DAPI positive cells were most increased in Group I. CONCLUSIONS: The transplantation of VEGF165-expressing MSCs had a better therapeutic effect than the transplantation of simplex MSCs. This combined strategy of MSCs transplantation with vgene therapy could be a useful therapy for the treatment of myocardial infarction.