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The high incidence of cardiovascular disease has led to significant demand for synthetic vascular grafts in clinical applications. Anti-proliferation drugs are usually loaded into devices to achieve desirable anti-thrombosis effects after implantation. However, the non-selectiveness of these conventional drugs can lead to the failure of blood vessel reconstruction, leading to potential complications in the long term. To address this issue, an asymmetric membrane was constructed through electro-spinning techniques. The bilayer membrane loaded and effectively released nitric oxide (NO), as hoped, from only one side. Due to the short diffusion distance of NO, it exerted negligible effects on the other side of the membrane, thus allowing selective regulation of different cells on both sides. The released NO boosted the growth of endothelial cells (ECs) over smooth muscle cells (SMCs)—while on the side where NO was absent, SMCs grew into multilayers. The overall structure resembled a native blood vessel, with confluent ECs as the inner layer and layers of SMCs to support it. In addition, the membrane preserved the normal function of ECs, and at the same time did not exacerbate inflammatory responses. By preparing this material type that regulates cell behavior differentially, we describe a new method for its application in the cardiovascular field such as for artificial blood vessels.

MicroRNA-125b (miR-125b) reduces myocardial infarct area and restrains myocardial ischemia reperfusion injury (I/R). In this study, we aimed to investigate the effect of bone marrow mesenchymal stem cell (BMSC)-derived exosomes carrying miR-125b on I/R rats. The myocardial I/R model in rats was constructed by ligation of the left anterior descending coronary artery (LAD). Rats were randomly divided into I/R and Sham group. Lv-cel-miR-67 (control) or Lv-miR-125b was transfected into BMSCs. Exosomes were extracted from transfected BMSCs, and separately named BMSC-Exo-67, BMSC-Exo-125b, and BMSC-Exo. MTT assay and flow cytometry were used to detect the viability and apoptosis of I/R myocardium cells, respectively. The expression of cell apoptosis proteins and the levels of inflammatory factors were examined by Western blot and ELISA assay, respectively. The target relationship between miR-125b and SIRT7 was predicted by using StarBase3.0, and was confirmed by using dual-luciferase reporter gene assay. qRT-PCR, immunohistochemistry staining, and Western blot were used to evaluate the expression of SIRT7 in myocardium tissues in I/R rats. BMSC-derived exosomes were successfully isolated and identified by TEM and positive expression of CD9 and CD63. The expression of miR-125b was down-regulated in I/R myocardium tissues and cells. BMSC-Exo-125b significantly up-regulated miR-125b in I/R myocardium cells. The intervention of BMSC-Exo-125b significantly increased the cell viability, decreased the apoptotic ratio, down-regulated Bax and caspase-3, up-regulated Bcl-2, and decreased the levels of IL-1β, IL-6, and TNF-α in I/R myocardium cells. SIRT7 was a target of miR-125b, and BMSC-Exo-125b significantly down-regulated SIRT7 in myocardium cells. In addition, the injection of BMSC-Exo-125b alleviated the pathological damages and down-regulated SIRT7 in myocardium tissues of I/R rats. BMSC-derived exosomes carrying miR-125b protected against myocardial I/R by targeting SIRT7.

The aim of our work was to test whether thymosin beta 4 protected endothelial progenitor cells against apoptosis induced by advanced glycation endproducts and investigate the underlying mechanism. Treatment with thymosin beta 4 or transfection with microRNA-34a inhibitor enhanced cell viability, reduced apoptosis, abated oxidative stress, and attenuated mitochondrial dysfunction in endothelial progenitor cells exposed to advanced glycation endproducts. Incubation with advanced glycation endproducts led to increased levels of microRNA-34a, which was attenuated by treatment with thymosin beta 4. Transfection with microRNA-34a reversed the beneficial effect of thymosin beta 4 against injuries induced by advanced glycation endproducts. The microRNA-34a could directly bind to the 3′UTRs of the mRNA of B-cell lymphoma 2, and thymosin beta 4 treatment upregulated B-cell lymphoma 2 expression in endothelial progenitor cells exposed to advanced glycation endproducts. More importantly, knockdown of B-cell lymphoma 2 abolished the protection of thymosin beta 4 and microRNA-34a inhibitor against advanced glycation endproducts. In conclusion, inhibition of microRNA-34a mediated protection of thymosin beta 4 in endothelial progenitor cells against advanced glycation endproducts by targeting B-cell lymphoma 2, which was helpful for understanding the therapeutic potential of thymosin beta 4 for diabetic patients.

Background: Dyslipidemia is one of the risks of coronary atherosclerosis disease (CAD). Intensive-dose statins or combining with ezetimibe are widely used to improve the lipid-lowering efficacy in the clinic. Recently, lipid variability has gradually gained attention to be a more reliable predictor of cardiovascular events. We aimed to investigate the variability in plasma lipids in the above two lipid-lowering strategy.Methods: It was a multicenter retrospective study, a total of 1275 patients with CAD from January 2009 to April 2019 were divided into 2 groups: intensive statins (atorvastatin 40 mg/d or rosuvastatin 20 mg/d) group and conventional-dose statins (atorvastatin 20 mg/d or rosuvastatin 10 mg/d) combined with ezetimibe group. All patients were followed up for at least 1-year. Multiple linear regression was used to analyze the association of two lipid-lowering regimens with plasma lipids variability; and subgroup analyses of the relevant factors were applied. All verifications are verified by standard deviation (SD), coefficient of variation (CV), and variability independent of mean (VIM) triple methods.Results: In the overall participants, the mean age was 62.3±10.4 years old, and 72.8% was male. Multivariate linear regression indicated that intensive statins group had lower variability in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) in all SD, CV, and VIM triple methods than statins combined with ezetimibe group (p for all Conclusions: Intensive statins therapy has lower variability in TC, LDL-C, and non-HDL-C, that is, better lipids stability than statins combined with ezetimibe therapy in patients with CAD.

Objectives The aim of the present study was to evaluate the angiographic efficacy, clinical safety, and effectiveness of the Restore paclitaxel-coated balloon in a randomized trial designed to enable the approval of the new device in China. Background Drug-coated balloon (DCB) angioplasty offers an effective treatment for in-stent restenosis. Restore is a new DCB with a SAFEPAX shellac-ammonium salt excipient that can avoid drug washing off during catheter delivery to the target lesion site. Methods In the noninferiority RESTORE ISR China (Compare the Efficacy and Safety of RESTORE DEB and SeQuent Please in Chinese Patient With Coronary In-stent Restenosis) trial, eligible patients with first occurrence of drug-eluting stent ISR were randomized to the Restore DCB or SeQuent Please DCB in a 1:1 ratio stratified by diabetes. Angiographic and clinical follow-up was planned at 9 months and 1 year, respectively, in all patients. The study was powered for the primary endpoint of 9-month in-segment late loss. Results Between May 2016 and July 2017, a total of 240 subjects at 12 sites were randomized to either the Restore group (n = 120) or the SeQuent Please group (n = 120). Nine-month in-segment late loss was 0.38 ± 0.50 mm with Restore versus 0.35 ± 0.47 mm with SeQuent Please; the 1-sided 97.5% upper confidence limit of the difference was 0.17 mm, achieving noninferiority of Restore compared with SeQuent Please (p for noninferiority = 0.02). Both DCBs had similar 1-year rates of target lesion failure (13.3% vs. 12.6%; p = 0.87). Conclusions In this head-to-head randomized trial, the Restore DCB was noninferior to the SeQuent Please DCB for the primary endpoint of 9-month in-segment late loss. (Compare the Efficacy and Safety of RESTORE DEB and SeQuent Please in Chinese Patient With Coronary In-stent Restenosis; NCT02944890)

Farnesyl pyrophosphate synthase (FPPS)-catalyzed isoprenoid intermediates are involved in diabetic cardiomyopathy. This study investigated the specific role of FPPS in the development of diabetic cardiomyopathy. We demonstrated that FPPS expression was elevated in both in vivo and in vitro models of diabetic cardiomyopathy. FPPS inhibition decreased the expression of proteins related to cardiac fibrosis and cardiomyocytic hypertrophy, including collagen I, collagen III, connective tissue growth factor, natriuretic factor, brain natriuretic peptide, and β-myosin heavy chain. Furthermore, FPPS inhibition and knockdown prevented phosphorylated c-Jun N-terminal kinase 1/2 (JNK1/2) activation in vitro. In addition, a JNK1/2 inhibitor downregulated high-glucose-induced responses to diabetic cardiomyopathy. Finally, immunofluorescence revealed that cardiomyocytic size was elevated by high glucose and was decreased by zoledronate, small-interfering farnesyl pyrophosphate synthase (siFPPS), and a JNK1/2 inhibitor. Taken together, our findings indicate that FPPS and JNK1/2 may be part of a signaling pathway that plays an important role in diabetic cardiomyopathy.

The objective of the research was to investigate the function of endothelial progenitor cells (EPCs) in the conditions of high glucose and lipids, which has been widely used to mimic the metabolic disorder that occurs in type 2 diabetic mellitus, and further to verify the role of PGC-1α and SIRT1, cellular energy metabolism regulators, in the process of senescence of EPCs with these combined stimuli. Circulating EPCs were incubated in absence or presence of high glucose (25 mM), FFA (200 μM) or both. EPCs senescence was assessed by β-galactosidase staining, EPCs telomerase activity was measured by telomeric repeat amplification protocol assay, in vitro angiogenesis assay and MTT assays were performed to assess angiogenesis and proliferation ability of EPCs. The results showed that combined stimuli inhibited EPCs reendothelialization ability in vitro, accelerated EPCs senescence and decreased the telomerase activity. Meanwhile, with combined stimuli, the expression of PGC-1α increased whereas SIRT1 expression decreased in EPCs accompanied by activation of P53/P21 signaling pathway. Conversely, transfection of EPCs with PGC-1α-siRNA rescued EPCs premature senescence and up-regulated SIRT1 and decreased P53/P21 expression, correlating closely with the down-regulation of PGC-1α itself. In addition, the combined stimuli induced up-regulation of PGC-1α expression was partly mediated by ROS and P38 signaling pathway. Overall, the data presented here identify PGC-1α as a potent negative regulator of EPCs' senescence under combined stimuli, which is partly mediated by SIRT1/P53/P21 signaling pathway.

Theaflavin 3,3'-digallate (TF3), is reported to protect cardiomyocytes from lipotoxicity and reperfusion injury. However, the role of TF3 in the protection of high-glucose injury is still poorly understood. This study investigated the protective effects of TF3 on gap junctions and autophagy in neonatal cardiomyocytes (NRCMs). NRCMs preincubated with high glucose were coincubated with TF3. The expression of connexins and autophagy-related proteins was determined. The functioning of gap-junctional intercellular communication (GJIC) was measured by a dye transfer assay. Adenosine monophosphate-activated protein kinase (AMPK) activity was determined by western blot. Moreover, AMPK was activated with aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) or inhibited by AMPKα small interfering RNA (siRNA) to explore the role of AMPK in the modulation of connexin 43 (Cx43) and autophagy. Meanwhile, autophagy was activated or blocked to observe the change in Cx43 expression. It was found that the protein expression of Cx43 and autophagy-related proteins was increased in a TF3 dose- and time-dependent manner under high glucose. TF3 also recovered the reduced GJIC function induced by high glucose concentrations. TF3 activated phosphorylated AMPK in a time-dependent way. AMPKα siRNA abrogated the protection of TF3, while AICAR showed similar results compared to the TF3 treatment. Meanwhile, autophagy activation caused decreased Cx43, while cotreatment with baf A1 enhanced Cx43 expression further compared with the TF3 treatment alone under high glucose. We concluded that TF3 partly reversed the inhibition of Cx43 expression and autophagy induced by high glucose in NRCMs, partly by restoring AMPK activity. Inhibition of autophagy might be protective by preserving Cx43 expression in NRCMs stimulated by high glucose.

More and more evidence suggests that the density of calcification plays an important role in the plaque stability. However, few studies have investigated the statin treatment on the density of plaque calcification in patients with both coronary artery disease (CAD) and type 2 diabetes mellitus. One hundred and twenty-two CAD patients with type 2 diabetes with confirmed coronary artery calcification (CAC) will be recruited consecutively in a 12-month period. These patients will receive rosuvastatin (20 mg/day) therapy in the next 24 months. Blood tests and adverse events will be collected at routine follow-up of 1, 3, 6, 12, 18 and 24 months. The primary endpoint will be the change of CAC density score measured by coronary CT angiography after 24 months’ treatment of rosuvastatin (20 mg/day) compared with baseline. The secondary endpoints will be the change of serum sclerostin and the effect on the volume score of CAC in those patients. We expect that rosuvastatin could both increase the density of CAC to improve plaque stability and up-regulate serum sclerostin, which would suggest the underlying mechanism of the plaque stabilization by a statin. This study would be the first to demonstrate the impact of rosuvastatin on the density score of coronary artery calcification in CAD patients with type 2 diabetes. This study has been registered in ClinicalTrials.gov (NCT02418884).

Objectives: The aim of this study was to evaluate the prevalence and long-term clinical impact of tissue protrusion (TP) after stent implantation.Background: Stent implantation may be assoc...

Circulating endothelial progenitor cells (EPCs) are a subtype of hematopoietic stem cells, which can differentiate into endothelial cells and restore endothelial function. However, high glucose decreases the number and impairs the function of EPCs. A previous study showed that thymosin β4 (Tβ4), a pleiotropic peptide beneficial for multiple functions of various types of cells, could promote EPC migration and dose-dependently upregulate the phosphorylation of Akt and endothelial nitric oxide synthesis signaling (eNOS). In present study, the hypothesis that Tβ4 can improve glucose-suppressed EPC functions via the Akt/eNOS signaling pathway and restores the production of nitric oxide (NO) is investigated. EPCs were isolated from the peripheral blood of healthy volunteers and formed a cobblestone shape after 3-4 weeks of cultivation. Then, EPCs were treated with high concentrations of glucose (25 mM) for 4 days and administrated with Tβ4 for further study. Transwell migration and tube formation assays were performed to access the migratory and angiogenic ability of EPCs. In addition, the quantity of Akt, eNOS and the concentration of nitric oxide (NO) was investigated. Functional studies showed that high concentrations of glucose significantly suppressed EPC function, while this adverse effect was reversed by the administration of Tβ4. In addition, Akt small interfering (si)RNA and eNOS siRNA were demonstrated to reduce the protective effect of Tβ4 against glucose-impaired EPC functions. These findings suggest that Tβ4 improves glucose-impaired EPC functions via the Akt/eNOS signaling pathway.

The objective of the research was to investigate the function of endothelial progenitor cells (EPCs) in the conditions of high glucose and lipids, which has been widely used to mimic the metabolic disorder that occurs in type 2 diabetic mellitus, and further to verify the role of PGC-1α and SIRT1, cellular energy metabolism regulators, in the process of senescence of EPCs with these combined stimuli. Circulating EPCs were incubated in absence or presence of high glucose (25 mM), FFA (200 µM) or both. EPCs senescence was assessed by β-galactosidase staining, EPCs telomerase activity was measured by telomeric repeat ampli-fication protocol assay, in vitro angiogenesis assay and MTT assays were performed to assess angiogenesis and proliferation ability of EPCs. The results showed that combined stimuli inhibited EPCs reendothelialization ability in vitro, accelerated EPCs senescence and decreased the telomerase activity. Meanwhile, with combined stimuli, the expression of PGC-1α increased whereas SIRT1 expression decreased in EPCs accompanied by activation of P53/P21 signaling pathway. Conversely, transfection of EPCs with PGC-1α-siRNA rescued EPCs premature senescence and up-regulated SIRT1 and decreased P53/P21 expression, correlating closely with the down-regulation of PGC-1α itself. In addition, the combined stimuli induced up-regulation of PGC-1α expression was partly mediated by ROS and P38 signaling pathway. Overall, the data presented here identify PGC-1α as a potent negative regulator of EPCs' senescence under combined stimuli, which is partly mediated by SIRT1/P53/P21 signaling pathway.

Diabetes Mellitus is a common disorder, with increasing risk of cardiac arrhythmias. Studies have shown that altered connexin expression and gap junction remodeling under hyperglycemia contribute to the high prevalence of cardiac arrhythmias and even sudden death. Connexin 43 (Cx43), a major protein that assembles to form cardiac gap junctions, has been found to be downregulated under high glucose conditions, along with inhibition of gap junctional intercellular communication (GJIC). While, apelin, a beneficial adipokine, increases Cx43 protein expression in mouse and human embryonic stem cells during cardiac differentiation. However, it remains unknown whether apelin influences GJIC capacity in cardiomyocytes. Here, using Western blotting and dye transfer assays, we found that Cx43 protein expression was reduced and GJIC was impaired after treatment with high glucose, which, however, could be abrogated after apelin treatment for 48 h. We also found that apelin increased Cx43 expression under normal glucose. Real-time PCR showed that the Cx43 mRNA was not significantly affected under high glucose conditions in the presence of apelin or high glucose and apelin. High glucose decreased the phosphorylation of AMPKα; however, apelin activated AMPKα. Interestingly, we found that Cx43 expression was increased after treatment with AICAR, an activator of AMPK signaling. AMPKα inhibition mediated with transfection of siRNA-AMPKα1 and siRNA-AMPKα2 abolished the protective effect of apelin on Cx43 expression. Our data suggest that apelin attenuates high glucose-induced Cx43 downregulation and improves the loss of functional gap junctions partly through the AMPK pathway.

We previously demonstrated that thymosin β4 (Tβ4) regulates a variety of endothelial progenitor cell (EPC) functions, including cell migration, proliferation, survival and angiogenesis. However, the effect of Tβ4 on the senescence of circulating EPCs remains unclear. In the present study, the effect of Tβ4 on EPC senescence and the signal transduction pathways involved in this process was investigated. Circulating EPCs isolated from healthy volunteers were cultured in the absence or presence of Tβ4 and various signal cascade inhibitors. Tβ4 inhibited EPC senescence in a concentration‑dependent manner. In addition, Tβ4 increased telomerase activity and expression of telomerase reverse transcriptase mRNA in EPCs. Tβ4 also regulated the expression of p21, p27 and cyclin D1. The effects of Tβ4 on EPC senescence were eliminated by the phosphoinositide 3'‑kinase (PI3K) inhibitor, wortmannin and the endothelial nitric oxide synthase inhibitor, L‑nitroarginine methyl ester hydrochloride (L‑NAME). In conclusion, the inhibitory effect on EPC senescence mediated by Tβ4 may be attributed, at least in part, to activation of the PI3K‑Akt‑eNOS signaling pathway.

The aim of this study was to evaluate the prevalence and long-term clinical impact of tissue protrusion (TP) after stent implantation.Stent implantation may be associated with tissue (plaque or thrombus) protrusion, especially in unstable lesions, but its clinical impact is unknown.ADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) was a prospective multicenter study of 8,663 patients undergoing percutaneous coronary intervention (PCI) using drug-eluting stents. In a pre-specified intravascular ultrasound (IVUS) substudy, 2,072 patients with 2,446 culprit lesions underwent post-PCI IVUS (among whom some also underwent pre-PCI IVUS) and were classified according to the presence or absence of post-stent TP.After PCI, 34.3% of lesions displayed TP on IVUS. Median maximum TP was 0.7 mm(2) (interquartile range: 0.5 to 1.2 mm(2)) in area and 3.0 mm (interquartile range: 1.4 to 6.7 mm) in length. Patients with TP more often presented with ST-segment elevation myocardial infarction or non-ST-segment elevation myocardial infarction but less often with unstable angina or stable ischemic heart disease. In 893 culprit lesions that were also examined pre-PCI, TP was associated with larger reference luminal area, greater plaque burden, and more plaque ruptures, attenuated plaque, and virtual histology thin-cap fibroatheromas. Because a larger stent or post-dilation balloon was used, post-PCI luminal area was significantly larger in lesions with versus without TP. At 2-year follow-up, there was less clinically driven target lesion revascularization in lesions with TP and no significant difference in major adverse cardiac events (defined as cardiac death, myocardial infarction, or stent thrombosis) in patients with versus without TP.IVUS-detected TP after drug-eluting stent implantation was not associated with worse long-term clinical outcomes, in part because of greater stent expansion in lesions with TP.

Thymosin β4 (Tβ4) has been suggested to regulate multiple cell signal pathways and a variety of cellular functions such as cell migration, proliferation, survival, and angiogenesis. Here, we investigated the effect of Tβ4 on endothelial progenitor cells (EPCs) apoptosis induced by serum deprivation and the corresponding signal transduction pathways involved in this process. Circulating EPCs, isolated from healthy volunteers, were cultured in the absence or presence of Tβ4 and various signal cascade inhibitors. Apoptosis was evaluated with Annexin V immunostaining and cytosolic cytochrome c expression. Incubation of EPCs with Tβ4 caused a concentration dependent increase in cell viability and proliferation activity. It also caused an inhibitory effect on EPCs apoptosis, which was abolished by PI3K inhibitors (either LY294002 or Wortmannin) or JNK MAPK inhibitor SP600125. In addition, the expression and activity of caspase-3 and -9 were decreased by Tβ4, which markedly increased the Bcl-2/Bax ratio within EPCs. Furthermore, Tβ4 was immunoprecipitated with integrin-linked kinase (ILK), accompanied by augmentation of ILK activity. Transfection of EPCs with ILK-siRNA resulted in abolishment of the activation of ILK-Akt and the ameliorative effect on apoptosis by Tβ4. Together, Tβ4 mediated inhibitory effect on EPCs apoptosis under serum deprivation can be attributed, at least in part, to ILK-Akt activation. The activation of JNK MAPK might also be involved in this process.

Intercellular communication through gap junctions (GJIC) plays an essential role in maintaining the functional integrity of vascular endothelium. Despite emerging evidence suggests that (-)-Epigallocatechin gallate (EGCG) may improve endothelial function. However, its effect on Cx43 gap junction in endothelial cells remains unexplored. Here we investigated the effect of EGCG on connexin43 (Cx43) gap junction in endothelial cells. The levels of Cx43 protein in human umbilical vein endothelial cells (HUVECs) cultured under serum-deprivation 48 h decreased about 50%, accompanied by decreased GJIC. This reduction can be reversed by treatments with EGCG. In addition, EGCG activated ERK, P38, and JNK mitogen-activated protein kinases (MAPKs), which were supposed to participate in the regulation of Cx43. A MEK inhibitor PD98059, but not SB203580 (a p38 kinase inhibitor) or SP600125 (a JNK kinase inhibitor), abolished the effects of EGCG on Cx43 expression and GJIC. Moreover, although both Akt and eNOS phosphorylation were time-dependently augmented by EGCG, neither PI3K inhibitor LY294002 nor eNOS inhibitor L-NAME blocked the effects of EGCG on Cx43 gap junctions. Thus, EGCG attenuated Cx43 down-regulation and impaired GJIC induced by serum deprivation, ERK MAPK Signal transduction pathway appears to be involved in these processes.

Endothelialization and antithrombogenicity are two key issues in stent implantation. The layer-by-layer (LbL) deposition of anticoagulant heparin and cell compatible collagen was explored to develop a multilayered coating with synergic property of antithrombogenicity and fast endothelialization. The quartz crystal microbalance with dissipation (QCM-D), UV spectrometer, spectroscopic ellipsometry, scanning electron microscopy, and confocal laser scanning microscopy investigations indicate that the LbL technique, which based on molecular assembly, provides an easy way to develop a smooth, homogenous, and stable coating onto stents. In vitro blood clotting time tests and the platelet adhesion tests show that the multilayer-modified stents present good hemocompatibility. In vitro endothelial cell (EC) culture results show that the multilayer-modified surfaces accelerate the adhesion and proliferation of ECs. These results illustrate that a stent surface coating with properties of antithrombogenicity and EC preference was obtained via heparin/collagen multilayer modification. This surface coating may have great potential in facilitating in situ endothelialization of blood contacting materials.

Thymosin beta4, a G-actin-sequestering peptide, has been shown to play an important role in cell migration. However, little is known about the effect of thymosin beta4 on circulating endothelial progenitor cell (EPC) directional migration, which is essential for EPC-mediated reendothelialization and neovascularization. In our study, using a transwell migration assay, we showed that thymosin beta4 induced EPC migration in a concentration-dependent manner. Western blot analysis revealed that treatment of EPCs with thymosin beta4 resulted in a time and concentration-dependent phosphorylation of Akt, endothelial nitric oxide synthase (eNOS), and extracellular signal-regulated kinase (ERK)1/2. Functional analysis showed that thymosin beta4-induced EPC migration was blocked by phosphatidylinositol 3-kinase inhibitors (LY294002 or wortmannin) or eNOS inhibitor (Nomega-nitro-L-arginine methyl ester) but was not significantly attenuated by mitogen-activated protein kinase (MAPK)/ERK inhibitor (PD98059). These findings suggest that thymosin beta4 stimulates EPC directional migration via phosphatidylinositol 3-kinase/Akt/eNOS, rather than via MAPK/ERK signal transduction pathway.

Objectives Adverse effects of intracoronary injection of stem cells on in-stent restenosis and atherosclerotic progression remain unclear. We sought to evaluate the adverse effects of intracoronary injection of CD133 cells on in-stent restenosis and atherosclerotic progression in the infarct-related and contralateral arteries using serial intravascular ultrasound (IVUS) analysis. Methods Baseline and 4-month follow-up IVUS images were obtained from 17 patients treated with intracoronary stem cell injection and 20 placebo patients after primary percutaneous coronary intervention in the COMPARE-AMI trial. In the infarct-related artery, the stented segment, 5 mm proximal and distal reference segments, and proximal and distal nonstented segments were analyzed every 1 mm; the entire segment of a contralateral artery was also analyzed every 1 mm. Results In the infarct-related artery analysis, the median percentage of in-stent neointimal hyperplasia (12.1 vs. 7.6%, P=0.95), the reduction in the minimum lumen area (MLA; -1.6 vs. -1.5 mm(2), P=0.97), and the MLA at follow-up (4.3 vs. 5.3 mm(2), P=0.21) were found to be similar between the stem cell and placebo groups. Changes in proximal and distal nonstented segment lumen areas and plaque burden were also similar between the stem cell and placebo groups; however, there was a decrease in the maximum arc of the attenuated plaque behind the stent from baseline to follow-up in the placebo group (P=0.004), but not in the stem cell group. In the contralateral artery, there were no differences in changes in MLA, plaque burden, or attenuated plaque between stem cell and placebo patients. Conclusion Intracoronary injection of CD133(+) bone marrow stem cells has no IVUS-detectable effect on neointimal hyperplasia or atherosclerosis progression in either infarct-related or contralateral arteries.

Cardiac allograft vasculopathy is a major cause of morbidity and mortality among patients after heart transplantation. We sought to assess the amount of lipid accumulation in the coronary arteries of transplant patients according to rejection grade. Overall, 39 consecutive heart transplant recipients undergoing annual routine surveillance coronary angiography underwent near-infrared spectroscopy and intravascular ultrasound imaging of 1 coronary artery. Rejection history was graded according to the International Society of Heart and Lung Transplantation (ISHLT) classification as none/mild/moderate-grade rejection (ISHLT 0, 1A/1B, or 2) compared to high-grade rejection (≥3A). Patients with prior history of high-grade rejection had larger plaque burden in the distal coronary segments [45.7 % (25.5-63.7) vs 25.1 % (19.9-37.8), p = 0.02] and a higher maximum lipid core burden index in any 4-mm long segment (maxLCBI(4mm)) [243 (91-400) vs 41 (1-170), p = 0.016] as compared with patients with prior history of none/mild/moderate-grade rejection. By multivariable linear regression analysis, prior history of high-grade rejection was an independent predictor for maxLCBI(4mm). A maxLCBI(4mm) >200 distinguished prior history of high-grade from none/mild/moderate rejection with a sensitivity of 61.5 % and specificity of 84.6 %. The current study demonstrates that the coronary arteries of post heart-transplant patients with a prior history of high-grade cellular rejection have increasing amounts of lipid-rich plaque. MaxLCBI(4mm) >200 might differentiate patients with previous high-grade cellular rejection from heart transplant recipients with none/mild/moderate-grade rejection.

Aims The aim was to compare cardiac allograft vasculopathy to native atherosclerosis by near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). Methods and results Twenty-seven atherosclerotic (non-transplant) patients and 28 heart transplant recipients undergoing routine surveillance coronary angiography underwent NIRS-IVUS imaging of the left anterior descending coronary artery. In each proximal, middle, and distal coronary artery segment, the maxLCBI4mm [4-mm long segment with maximum lipid core burden index (LCBI)] and corresponding IVUS parameters were compared. MaxLCBI4mm was significantly greater among atherosclerotic patients than the transplant patients in both proximal and middle coronary artery segments, but not in the distal segment. There was a positive linear correlation between maxLCBI4mm and maximum plaque burden in both groups, but atherosclerotic patients demonstrated a smaller maxLCBI4mm than transplant recipients among segments with plaque burden

Peri-procedural myocardial infarction (peri-MI) is the result of distal embolization of lipid-core plaque debris and/or thrombus during percutaneous coronary intervention (PCI) and is associated with short- and long-term adverse events. The COLOR Registry was a prospective, multicenter

Recent studies have suggested that reduced endothelial progenitor subpopulation in lectin-binding and DiLDL-uptaking cell (EPC subpopulation) number and activity was associated with EPC subpopulation senescence that involved telomerase activity and telomere length. Stromal cell-derived factor-1α (SDF-1α) has been shown to augment a variety of cellular functions of EPC subpopulation and subsequently contribute to ischemic neovascularization. Therefore, we investigated whether SDF-1α might be able to prevent senescence of EPC subpopulation and also investigated the effects of SDF-1α on the telomerase activity and telomere length. EPC subpopulation were isolated from peripheral blood and characterized. After ex vivo prolonged cultivation, EPC subpopulation became senescent as determined by acidic β-galactosidase staining. SDF-1α dose-dependently inhibited the onset of EPC subpopulation senescence. Moreover, SDF-1α increased proliferation and colony-forming activity of EPC subpopulation. SDF-1α also increased telomerase activity and telomere length, which was accompanied with upregulation of the catalytic subunit, telomerase reverse transcriptase (TERT). Whereas these effects of SDF-1α on telomerase activity and expression of hTERT mRNA were significantly attenuated by CXCR4-specific peptide antagonist (AMD3100) and phosphoinositide 3-kinase (PI3K) inhibitor (LY294002). In conclusions, SDF-1α delays the onset of EPC subpopulation senescence, which may be related to the activation of telomerase and elongation of telomere length. The inhibition of EPC subpopulation senescence and induction of EPC subpopulation proliferation by SDF-1α in vitro may importantly improve the functional activity of EPC subpopulation for potential cell therapy. J. Cell. Physiol. 223:757–763, 2010. © 2010 Wiley-Liss, Inc.

The in-stent restenosis (ISR) and the late stent thrombosis (LAST) represent the most common failures of stent implantation and are both mediated at the injured endothelium. The natural endothelium healing mechanism provides an approach to achieve in situ endothelialization of the implant by stimulating the neighboring endothelial cells (ECs) migration or capturing the circulating endothelial cells (CEC) directly from the blood circulation. An anti-CD34 antibody functionalized multilayer of heparin/collagen is developed here via layer-by-layer assemble. The ellipsometry and QCM-D results demonstrate that the multilayer coatings with slight glutaraldehyde cross-linking are stable in static incubation and flushing conditions, respectively. The in vitro hemocompatibility tests and cell culture results indicate that both heparin/collagen multilayers with or without the anti-CD34 antibody functionalization not only preserve good hemocompatibility, but also promote cell attachment and growth notably. While the heparin/collagen multilayer coatings show no selectivity in promotion of ECs and smooth muscle cells (SMCs), the anti-CD34 antibody functionalized heparin/collagen multilayers can specifically promote the attachment and growth of the vascular ECs. The metabolic activity assessment and the NO secretion measurements further indicate that the adherent ECs on the anti-CD34 antibody functionalized heparin/collagen multilayer surface have better viability and possess the specific function of the natural vascular ECs. In vivo experiments indicate that the anti-CD34 antibody can enrich and accelerate the attachment of the vascular cells onto the stent and rapid endothelialization is realized. While no significant difference of neointimal hyperplasia is observed between the bare metal stents and heparin/collagen multilayer modified stents, the neointimal hyperplasia on the anti-CD34 antibody functionalized multilayer modified stents is significantly inhibited. The success of the anti-CD34 antibody functionalized heparin/collagen multilayer coating in rapid endothelialization and anti-restenosis might indicate that the immobilization of ECs specific ligand onto a cytocompatible matrix can be a good approach for in situ endothelialization and a possible solution to ISR.