GSEA analysis identifies potential drug targets and their interaction networks in coronary microcirculation disorders.

Coronary microcirculation dysfunction (CMD) is one of the main causes of cardiovascular disease. Traditional treatment methods lack specificity, making it difficult to fully consider the differences in patient conditions and achieve effective treatment and intervention. The complexity and diversity of CMD require more standardized diagnosis and treatment plans to clarify the best treatment strategy and long-term outcomes. The existing treatment measures mainly focus on symptom management, including medication treatment, lifestyle intervention, and psychological therapy. However, the efficacy of these methods is not consistent for all patients, and the long-term efficacy is not yet clear. GSEA is a bioinformatics method used to interpret gene expression data, particularly for identifying the enrichment of predefined gene sets in gene expression data. In order to achieve personalized treatment and improve the quality and effectiveness of interventions, this article combined GSEA (Gene Set Enrichment Analysis) technology to conduct in-depth research on potential drug targets and their interaction networks in coronary microcirculation dysfunctions. This article first utilized the Coremine medical database, GeneCards, and DrugBank public databases to collect gene data. Then, filtering methods were used to preprocess the data, and GSEA was used to analyze the preprocessed gene expression data to identify and calculate pathways and enrichment scores related to CMD. Finally, protein sequence features were extracted through the calculation of autocorrelation features. To verify the effectiveness of GSEA, this article conducted experimental analysis from four aspects: precision, receiver operating characteristic (ROC) curve, correlation, and potential drug targets, and compared them with Gene Regulatory Networks (GRN) and Random Forest (RF) methods. The results showed that compared to the GRN and RF methods, the average precision of GSEA improved by 0.11. The conclusion indicated that GSEA helped identify and explore potential drug targets and their interaction networks, providing new ideas for personalized quality of CMD.

Development and trends in research on hypertension and atrial fibrillation: A bibliometric analysis from 2003 to 2022.

BACKGROUND: This study aimed to comprehensively analyze research related to hypertension and atrial fibrillation, 2 common cardiovascular diseases with significant global public health implications, using bibliometric methods from 2003 to 2022. METHODS: From the Web of Science Core Collection database, literature on the theme of hypertension and atrial fibrillation was retrieved. Subsequently, comprehensive bibliometric analyses were conducted across multiple dimensions utilizing software tools such as VOSviewer, Citespace, Pajek, Scimago Graphica, and ClusterProfiler. These analyses encompassed examinations of the literature according to country/region, institution, authors, journals, citation relationships, and keywords. RESULTS: It revealed an increasing interest and shifting focus in research over the years. The analysis covered 7936 relevant publications, demonstrating a gradual rise in research activity regarding hypertension combined with atrial fibrillation over the past 2 decades, with a stable growth trend in research outcomes. Geographically, Europe and the Americas, particularly the United States, have shown the most active research in this field, while China has also gained importance in recent years. Regarding institutional contributions, internationally renowned institutions such as the University of Birmingham and the Mayo Clinic have emerged as core forces in this research direction. Additionally, Professor Lip Gregory, with his prolific research output, has stood out among numerous scholars. The American Journal of Cardiology has become a primary platform for publishing research related to hypertension and atrial fibrillation, highlighting its central role in advancing knowledge dissemination in this field. The research focus has shifted from exploring the pathophysiological mechanisms to investigating the treatment of complications and risk factors associated with hypertension and atrial fibrillation. Future research will focus on in-depth exploration of genetic and molecular mechanisms, causal relationship exploration through Mendelian randomization studies, and the application of machine learning techniques in prediction and treatment, aiming to promote the development of precision medicine for cardiovascular diseases. CONCLUSION: In conclusion, this study provides a comprehensive overview of the developmental trajectory of research on hypertension and atrial fibrillation, presenting novel insights into trends and future research directions, thus offering information support and guidance for research in this crucial field of cardiovascular medicine.

Correlation between dietary inflammation and mortality among hyperlipidemics.

BACKGROUND AND OBJECTIVE: Although the the Dietary Inflammatory Index (DII) serves to be one of the reliable indicator for hyperlipidaemia, there is still uncertainty about its relationship to prognosis in the hyperlipidaemic population. In current study, the DII levels were analyzed in relation to the mortality risk among among the hyperlipidaemic individuals with the aim of determining any prospective correlation. METHODS: 14,460 subjects with hyperlipidaemia from the 10-year (2001-2010) National Health and Nutrition Examination Survey (NHANES) were chosen for this study. The endpoint event for follow-up was all-cause mortality, and subjects were tracked for up to December 31, 2019, or death, whichever occurred first. The tertiles of the DII levels were utilized for categorizing the study population into three groups. Survival curves, Cox proportional hazards regression models, restricted cubic spline (RCS), subgroup and interaction analyses, and sensitivity analyses were employed sequentially for the purpose of evaluating the association of the DII with mortality. RESULTS: 3170 (21.92%) all-cause deaths were recorded during an average 148-month follow-up period. Kaplan-Meier survival curves indicated that the survival rate of participants divided into the low DII group was substantially improved compared to that of those in the higher DII group (log-rank P < 0.001). After controlling for confounders, higher levels of DII were observed to be meaningfully linked to an elevated risk of death, no matter whether DII was specified for the continuous (hazard ratio (HR): 1.06; 95% confidence interval (CI): 1.04-1.08) or the categorical variable (HR: 1.22; 95% CI: 1.11-1.33). The DII and mortality displayed a linear association, according to the RCS. Stratified and sensitivity analyses reinforced the proof that these findings were reliable. CONCLUSION: Among patients with hyperlipidaemia, the risk of death was positively and linearly linked with DII levels.

Myocardial Perfusion in ST-Segment Elevation Myocardial Infarction Patients After Percutaneous Coronary Intervention: Influencing Factors and Intervention Strategies.

Aim We aim to explore the factors influencing myocardial perfusion in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI) and evaluate the effects of different intervention strategies on myocardial perfusion improvement. Methods A retrospective analysis was conducted on 300 patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) at our hospital between January 2020 and December 2022. Based on post-procedural coronary angiography results using the thrombolysis in myocardial infarction (TIMI) blood flow grade and myocardial blush grade (MBG), patients were categorized into two groups: the normal perfusion group (TIMI grade 3 or MBG 2-3, n=180) and the impaired perfusion group (TIMI grades 0-2 or MBG 0-1, n=120). The impaired perfusion group was further divided using a random number table into the thrombus aspiration-only group (control group, n=60) and the thrombus aspiration combined with nicorandil group (nicorandil group, n=60). A 1:1 propensity score matching method was employed to adjust for baseline characteristics between the groups. Clinical characteristics, hematological parameters, coronary lesion features, and percutaneous coronary intervention (PCI) technical parameters were compared between the matched groups. Additionally, a multivariate logistic regression analysis was performed to identify independent risk factors influencing myocardial perfusion. Furthermore, the post-procedural myocardial perfusion, cardiac function, and clinical prognosis were compared between the control and nicorandil groups. Results After matching, the baseline characteristics of the two groups were compared. The impaired perfusion group had older age, higher proportion of male patients, higher rates of diabetes and hypertension, longer time from symptom onset to balloon dilation, higher peak cardiac troponin I (cTnI) levels, higher proportion of left main or multivessel involvement, heavier coronary lesion burden, and lower balloon inflation pressure (P<0.05). Multivariate logistic regression analysis revealed that age of ≥65 years (odds ratio {OR}=2.34, 95% confidence interval {CI}=1.23-4.46, P<0.01), time from symptom onset to balloon dilation of ≥6 hours (OR=3.12, 95% CI=1.67-5.83, P<0.01), peak cTnI level of ≥100 ng/mL (OR=4.27, 95% CI=2.18-8.36, P<0.01), left main or multivessel involvement (OR=2.86, 95% CI=1.51-5.41, P<0.01), and balloon inflation pressure of <8 atm (OR=3.45, 95% CI=1.79-6.65, P<0.01) were independent risk factors affecting myocardial perfusion. In the intervention analysis, the nicorandil group showed superior post-procedural TIMI blood flow grade, MBG, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) functional classification compared to the control group (P<0.05). During a six-month follow-up, the nicorandil group had a lower incidence of major adverse cardiovascular events (MACE) compared to the control group (P<0.05). Conclusion Age, time from symptom onset to balloon dilation, peak cTnI level, extent of coronary artery lesions, and balloon inflation pressure were identified as independent risk factors affecting myocardial perfusion in STEMI patients after PCI. Compared to simple thrombus aspiration, thrombus aspiration combined with nicorandil demonstrated better improvement in myocardial perfusion, cardiac function, and clinical outcomes for patients with impaired perfusion.

m 6A RNA Methylation Decreases Atherosclerotic Vulnerable Plaque Through Inducing T Cells

ABSTRACT Introduction: Knockdown of fat mass and obesity-associated gene (FTO) can induce N6-methyladenosine (m 6A) ribonucleic acid (RNA) methylation. The objective of this study was to explore the effect of m 6A RNA methylation on atherosclerotic vulnerable plaque by FTO knockdown. Methods: A total of 50 New Zealand white rabbits were randomly divided into pure high-fat group, sham operation group, vulnerable plaque group, empty load group, and FTO knockdown group (10 rabbits/group). Results: Flow cytometry showed that helper T (Th) cells in the FTO knockdown group accounted for a significantly higher proportion of lymphocytes than in the vulnerable plaque group and empty load group (P<0.05). Th cells were screened by cell flow. The level of m 6A RNA methylation in the FTO knockdown group was significantly higher than in the vulnerable plaque group and empty load group (P<0.05). The levels of total cholesterol, triglyceride, and low-density lipoprotein C were higher at the 12th week than at the 1st week, but the high-density lipoprotein C level was lower at the 12th week than at the 1st week. At the 12th week, the interleukin-7 level was significantly lower in the adeno-associated virus-9 (AVV9)-FTO short hairpin RNA group than in the control and AVV9-green fluorescent protein groups (P<0.001). Conclusion: After successfully establishing a vascular parkinsonism rabbit model, m 6A RNA methylation can decrease Th cells and vulnerable atherosclerotic plaques.

m6A RNA Methylation Decreases Atherosclerotic Vulnerable Plaque Through Inducing T Cells.

INTRODUCTION: Knockdown of fat mass and obesity-associated gene (FTO) can induce N6-methyladenosine (m6A) ribonucleic acid (RNA) methylation. The objective of this study was to explore the effect of m 6A RNA methylation on atherosclerotic vulnerable plaque by FTO knockdown. METHODS: A total of 50 New Zealand white rabbits were randomly divided into pure high-fat group, sham operation group, vulnerable plaque group, empty load group, and FTO knockdown group (10 rabbits/group). RESULTS: Flow cytometry showed that helper T (Th) cells in the FTO knockdown group accounted for a significantly higher proportion of lymphocytes than in the vulnerable plaque group and empty load group (P<0.05). Th cells were screened by cell flow. The level of m6A RNA methylation in the FTO knockdown group was significantly higher than in the vulnerable plaque group and empty load group (P<0.05). The levels of total cholesterol, triglyceride, and low-density lipoprotein C were higher at the 12th week than at the 1st week, but the high-density lipoprotein C level was lower at the 12th week than at the 1st week. At the 12th week, the interleukin-7 level was significantly lower in the adeno-associated virus-9 (AVV9)-FTO short hairpin RNA group than in the control and AVV9-green fluorescent protein groups (P<0.001). CONCLUSION: After successfully establishing a vascular parkinsonism rabbit model, m6A RNA methylation can decrease Th cells and vulnerable atherosclerotic plaques.

Study on Connective Tissue Growth Factor Expressed in Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: This study measured the change in connective tissue growth factor levels after the onset of unstable angina and ST-segment elevation myocardial infarction, and studied its correlation with peak creatine kinase-MB (CK-MB) enzyme. It also discussed the significance of myocardial fibrosis after myocardial infarction. To detect the serum levels of connective tissue growth factor in patients with ST-segment elevation myocardial infarction and its relationship with the maximum level of CK-MB. METHODS: We selected 50 patients with ST-segment elevation myocardial infarction and 50 patients with unstable angina. Connective tissue growth factor levels were examined 24 h, 2 d, 7 d, and 14 d after the onset of ST-segment elevation myocardial infarction, and within 24 h for unstable angina, using enzyme-linked immunosorbent assay (ELISA). The maximum level of CK-MB was detected by immunosuppression. RESULTS: The serum level of connective tissue growth factor in the unstable angina patients was 10.34 ± 2.00 ng/mL, and the levels in the ST-segment elevation myocardial infarction patients were 16.76 ± 3.17 ng/mL at 24 h, 29.87 ± 4.90 ng/mL at 2 d, 45.02 ± 8.35 ng/mL at 7 d, and 31.61 ± 4.40 ng/mL at 14 d. Compared with the unstable angina patients, the connective tissue growth factor levels in the ST-segment elevation myocardial infarction patients were significantly higher since day 1 (p < 0.01). The maximum level of CK-MB was correlated with connective tissue growth factor levels at 7 d (r = 0.859, p = 0.000). CONCLUSIONS: Connective tissue growth factor was significantly expressed in the ST-segment elevation myocardial infarction patients, indicating that it might play an important role in myocardial fibrosis.

Predictive value of neutrophil to lymphocyte ratio in patients with acute ST segment elevation myocardial infarction after percutaneous coronary intervention: a meta-analysis.

BACKGROUND: The neutrophil to lymphocyte ratio (NLR) is an indicator of systemic inflammation and a prognostic marker in patients with acute coronary syndrome (ACS). This study aims to investigate the value of NLR to predict the in-hospital and long-term prognosis in patients with ST segment elevation myocardial infarction (STEMI) after percutaneous coronary intervention (PCI) by meta-analysis. METHOD: The studies related to the prognosis of NLR and STEMI patients published in the Pubmed, Embase, and Ovid databases before June 2017 were retrieved. The relevant data were extracted. Review Manager Version 5.3 was used for meta-analysis. RESULTS: A total of 14 studies of 10,245 patients with STEMI after PCI were included. A significant difference was observed for mortality (P < 0.001; relative risk (RR) 3.32; 95% confidence interval (CI) 2.45-4.49), hospital cardiac mortality(P < 0.001; RR 3.22; 95% CI 2.25-4.60), all mortality (P < 0.001; RR 3.23; 95% CI 2.28-4.57), major adverse cardiovascular events (MACE) (P < 0.001; RR 2.00; 95% CI 1.62-2.46), in-stent thrombosis (P < 0.001; RR 2.72 95% CI 1.66-4.44), nonfatal myocardial infarction(MI) (P < 0.001; RR 1.93; 95%CI 1.43-2.61), angina (P = 0.007; RR 1.67; 95%CI 1.15-2.41), advanced heart failure (AHF) (P < 0.001; RR 1.81; 95% CI 1.48-2.21), arrhythmia (P = 0.002; RR 1.38; 95% CI 1.13-1.69), no reflow (P < 0.001; RR 2.28; 95% CI 1.46-3.57), long-term all mortality (P < 0.001; RR 3.82; 95% CI 2.94-4.96), cardiac mortality (P = 0.004; RR 3.02; 95% CI 1.41-6.45), MACE (P < 0.001; RR 2.49; 95% CI 1.47-4.23), and nonfatal MI (P = 0.46; RR 1.32; 95% CI 0.63-2.75). CONCLUSIONS: Meta-analysis shows that NLR is a predictor of hospitalization and long-term prognosis in patients with STEMI after PCI, but requires further confirmation by large randomized clinical trials.

The efficacy and safety of tofacitinib in Asian patients with moderate to severe chronic plaque psoriasis: A Phase 3, randomized, double-blind, placebo-controlled study.

BACKGROUND: Tofacitinib is an oral Janus kinase inhibitor. OBJECTIVE: This study assessed tofacitinib efficacy and safety vs placebo in Asian patients with moderate to severe chronic plaque psoriasis. METHODS: Patients from China mainland, Taiwan, and Korea were randomized 2:2:1:1 to tofacitinib 5mg (N=88), tofacitinib 10mg (N=90), placebo→5mg (N=44), or placebo→10mg (N=44), twice daily (BID) for 52 weeks. Placebo-treated patients advanced to tofacitinib at Week 16. Co-primary efficacy endpoints: proportions of patients achieving Physician's Global Assessment (PGA) response ('clear' or 'almost clear') and proportion achieving ≥75% reduction from baseline Psoriasis Area and Severity Index (PASI75) at Week 16. RESULTS: At Week 16, more patients achieved PGA and PASI75 responses with tofacitinib 5mg (52.3%; 54.6%) and 10mg (75.6%; 81.1%) BID vs placebo (19.3%; 12.5%; all p<0.0001). Of patients with a Week 16 response, 73.6% and 75.0% maintained PGA response, and 76.8% and 84.9% maintained PASI75 to Week 52 with tofacitinib 5mg and 10mg BID, respectively. Over 52 weeks, 2.2-4.5% of patients across treatment groups experienced serious adverse events, and 1.1-6.8% discontinued due to adverse events. CONCLUSION: Tofacitinib demonstrated efficacy vs placebo at Week 16 in Asian patients with moderate to severe plaque psoriasis; efficacy was maintained through Week 52. No unexpected safety findings were observed. [NCT01815424].

Experimental study of USPIO-enhanced MRI in the detection of atherosclerotic plaque and the intervention of atorvastatin.

Ultrasmall superparamagnetic iron oxide (USPIO) can identify atherosclerotic vulnerable plaque and atorvastatin can stabilize vulnerable plaque by inhibiting the inflammatory response. Using balloon injury in rabbit abdominal aortic endothelial cells and p53 gene transfecting the local plaque, we established an atherosclerotic vulnerable plaque model. In the treatment group, animals were treated with atorvastatin for 8 weeks. At the end of week 16, the animals in each group underwent medication trigger. USPIO-enhanced MRI was utilized to detect vulnerable plaque formation and the transformation of stable plaque in the treatment group. Pathological and serological studies were conducted in animal sera and tissues. The images from the USPIO-enhanced MRI, and the vulnerable plaque showed low signal, especially on T2*-weighted sequences (T2*WI). Plaque signal strength reached a negative enhancement peak at 96 h. Compared with the other groups, lipids, cell adhesion molecule-1 and vascular cell adhesion molecule-1 levels were significantly lower (P<0.05) in the treatment group. In conclusion, USPIO-enhanced MRI can identify vulnerable plaque formation by deposition in macrophages, while atorvastatin is able to inhibit the progression of atherosclerosis and promote plaque transformation to the stable form.

Identifying Vulnerable Atherosclerotic Plaque in Rabbits Using DMSA-USPIO Enhanced Magnetic Resonance Imaging to Investigate the Effect of Atorvastatin.

BACKGROUND: Rupture of an atherosclerotic plaque is the primary cause of acute cardiovascular and cerebrovascular syndromes. Early and non-invasive detection of vulnerable atherosclerotic plaques (VP) would be significant in preventing some aspects of these syndromes. As a new contrast agent, dimercaptosuccinic acid (DMSA) modified ultra-small super paramagnetic iron oxide (USPIO) was synthesized and used to identify VP and rupture plaque by magnetic resonance imaging (MRI). METHODS: Atherosclerosis was induced in male New Zealand White rabbits by feeding a high cholesterol diet (n = 30). Group A with atherosclerosis plaque (n = 10) were controls. VP was established in groups B (n = 10) and C (n = 10) using balloon-induced endothelial injury of the abdominal aorta. Adenovirus-carrying p53 genes were injected into the aortic segments rich in plaques after 8 weeks. Group C was treated with atorvastatin for 8 weeks. Sixteen weeks later, all rabbits underwent pharmacological triggering, and imaging were taken daily for 5 d after DMSA-USPIO infusion. At the first day and before being killed, serum MMP-9, sCD40L, and other lipid indicators were measured. RESULTS: DMSA-USPIO particles accumulated in VP and rupture plaques. Rupture plaques appeared as areas of hyper-intensity on DMSA-USPIO enhanced MRI, especially T2*-weighted sequences, with a signal strength peaking at 96 h. The group given atorvastatin showed few DMSA-USPIO particles and had lower levels of serum indicators. MMP-9 and sCD40L levels in group B were significantly higher than in the other 2 groups (P <0.05). CONCLUSION: After successfully establishing a VP model in rabbits, DMSA-USPIO was used to enhance MRI for clear identification of plaque inflammation and rupture. Rupture plaques were detectable in this way probably due to an activating inflammatory process. Atorvastatin reduced the inflammatory response and stabilizing VP possibly by decreasing MMP-9 and sCD40L levels.

Detection of Vulnerable Atherosclerotic Plaques in Experimental Atherosclerosis with the USPIO-Enhanced MRI.

This study's goal was to assess the diagnostic value of the USPIO-(ultra-small superparamagnetic iron oxide) enhanced magnetic resonance imaging (MRI) in detection of vulnerable atherosclerotic plaques in abdominal aorta in experimental atherosclerosis. Thirty New Zealand rabbits were randomly divided into two groups, Group A and Group B. Each group comprised 15 animals which were fed with high cholesterol diet for 8 weeks and then subjected to balloon-induced endothelial injury of the abdominal aorta. After another 8 weeks, animals in Group B received adenovirus carrying p53 gene that was injected through a catheter into the aortic segments rich in plaques. Two weeks later, all rabbits were challenged with the injection of Chinese Russell's viper venom and histamine. Pre-contrast images and USPIO-enhanced MRI images were obtained after pharmacological triggering with injection of USPIO for 5 days. Blood specimens were taken for biochemical and serological tests at 0 and 18 weeks. Abdominal aorta was histologically studied. The levels of serum ICAM-1 and VCAM-1 were quantified by ELISA. Vulnerable plaques appeared as a local hypo-intense signal on the USPIO-enhanced MRI, especially on T2*-weighted sequences. The signal strength of plaques reached the peak at 96 h. Lipid levels were significantly (p < 0.05) higher in both Group A and B compared with the levels before the high cholesterol diet. The ICAM-1 and VCAM-1 levels were significantly (p < 0.05) higher in Group B compared with Group A. The USPIO-enhanced MRI efficiently identifies vulnerable plaques due to accumulation of USPIO within macrophages in abdominal aorta plaques.

CT/fluorescence dual-modal nanoemulsion platform for investigating atherosclerotic plaques.

Macrophages have become widely recognized as a key target for atherosclerosis imaging, since they contribute significantly to the progression of atherosclerosis. Dual-modal imaging contrast agents with unique X-ray computed tomography (CT) and optical imaging capabilities have great potential in disease diagnosis because of complementary combination of the high spatial resolution of CT with the high sensitivity of optical imaging. Here, a kind of quantum dots (QDs)-iodinated oil nanoemulsion of 80 nm was developed as a CT/fluorescence dual-modal contrast agent. Hydrophobic QDs were embedded in iodinated oil, which subsequently dispersed in water to form the oil-in-water nanoemulsion. The morphology and hydrodynamic size of the nanoemulsion were characterized, CT values and fluorescence properties were detected. Its cytotoxicity and affinity to three different cells were determined in vitro by MTT assay. In vitro Micro-CT and confocal microscopy cell imaging ability of the nanoemulsion were confirmed by co-incubating with murine macrophage cells and human liver cells. Then in vivo accumulation of this nanoemulsion in macrophages in atherosclerotic rabbits was investigated with clinic CT and fluorescence imaging. The results not only indicated the nanoemulsion could be served as a dual-modal contrast agent, but revealed it could specifically target to macrophages and visualize atherosclerotic plaques.

Efficiently tracking of stem cells in vivo using different kinds of superparamagnetic iron oxide in swine with myocardial infarction.

BACKGROUND: Superparamagnetic iron oxide (SPIO) particles have shown much promise as a means to visualize labeled cells using molecular magnetic resonance imaging (MRI). Micrometer-sized superparamagnetic iron oxide (MPIO) particles and nanometer-sized ultrasmall superparamagnetic iron oxide (USPIO) are two kinds of SPIO widely used for monitoring stem cells migration. Here we compare the efficiency of two kinds of SPIO during the use of stem cells to treat acute myocardial infarction (AMI). METHODS: An AMI model in swine was created by 60 minutes of balloon occlusion of the left anterior descending coronary artery. Two kinds of SPIO particles were used to track after intracoronary delivered 10(7) magnetically labeled mesenchymal stem cells (MR-MSCs). The distribution and migration of the MR-MSCs were assessed with the use of 3.0T MR scanner and then the results were confirmed by histological examination. RESULTS: MR-MSCs appeared as a local hypointense signal on T2*-weighted MRI and there was a gradual loss of the signal intensity after intracoronary transplantation. All of the hypointense signals in the USPIO-labeled group were found on T2*-weighted MRI, contrast to noise ratio (CNR) decreased in the MPIO-labeled group (16.07 ± 5.85 vs. 10.96 ± 1.34) and USPIO-labeled group (11.72 ± 1.27 vs. 10.03 ± 0.96) from 4 to 8 weeks after transplantation. However, the hypointense signals were not detected in MPIO-labeled group in two animals. MRI and the results were verified by histological examination. CONCLUSIONS: We demonstrated that two kinds of SPIO particles in vitro have similar labeling efficiency and viability. USPIO is more suitable for labeling stem cells when they are transplanted via a coronary route.

Detection of quantitative trait loci affecting haematological traits in swine via genome scanning.

BACKGROUND: Haematological traits, which consist of mainly three components: leukocyte traits, erythrocyte traits and platelet traits, play extremely important role in animal immune function and disease resistance. But knowledge of the genetic background controlling variability of these traits is very limited, especially in swine. RESULTS: In the present study, 18 haematological traits (7 leukocyte traits, 7 erythrocyte traits and 4 platelet traits) were measured in a pig resource population consisting of 368 purebred piglets of three breeds (Landrace, Large White and Songliao Black Pig), after inoculation with the swine fever vaccine when the pigs were 21 days old. A whole-genome scan of QTL for these traits was performed using 206 microsatellite markers covering all 18 autosomes and the X chromosome. Using variance component analysis based on a linear mixed model and the false discovery rate (FDR) test, 35 QTL with FDR < 0.10 were identified: 3 for the leukocyte traits, 28 for the erythrocyte traits, and 4 for the platelet traits. Of the 35 QTL, 25 were significant at FDR < 0.05 level, including 9 significant at FDR < 0.01 level. CONCLUSIONS: Very few QTL were previously identified for hematological traits of pigs and never in purebred populations. Most of the QTL detected here, in particular the QTL for the platelet traits, have not been reported before. Our results lay important foundation for identifying the causal genes underlying the hematological trait variations in pigs.

HO-1 gene overexpression enhances the beneficial effects of superparamagnetic iron oxide labeled bone marrow stromal cells transplantation in swine hearts underwent ischemia/reperfusion: an MRI study.

To determine the effect of intracoronary transfer of superparamagnetic iron oxide (SPIO) labeled heme oxygenase-1 (HO-1) overexpressed bone marrow stromal cells (BMSCs) in a porcine myocardial ischemia/reperfusion model. Cell apoptosis was assayed and supernatant cytokine concentrations were measured in BMSCs that underwent hypoxia/reoxygen in vitro. Female mini-swines that underwent 1 h LAD occlusion followed by 1 h reperfusion were randomly allocated to receive intracoronary saline (control), 1 x 10(7) SPIO-labeled BMSCs transfected with pcDNA3.1-Lacz plasmid (Lacz-BMSCs), pcDNA3.1-human HO-1 (HO-1-BMSCs), pcDNA3.1-hHO-1 pretreated with a HO inhibitor, tin protoporphyrin (SnPP, n = 10 each). MRI and postmortem histological analysis were made at 1 week or 3 months thereafter. Post hypoxia/reoxygen in vitro, apoptosis was significantly reduced, supernatant VEGF significantly increased while TNF-alpha and IL-6 significantly reduced in HO-1-BMSCs group compared with Lacz-BMSCs group (all p < 0.05). Myocardial expression of VEGF was significantly higher in HO-1-BMSCs than in Lacz-BMSCs group at 1 week post transplantation (all p < 0.05). Signal voids induced by the SPIO were detected in the peri-infarction region in all BMSC groups at 1 week but not at 3 months post transplantation and the extent of the hypointense signal was the highest in HO-1-BMSCs group, and histological analysis showed that signal voids represented cardiac macrophages that engulfed the SPIO-labeled BMSCs. Pretreatment with SnPP significantly attenuated the beneficial effects of HO-1-BMSCs. Transplantation of HO-1-overexpressed BMSCs significantly enhanced the beneficial effects of BMSCs on improving cardiac function in this model.

[Effects of autologous mesenchymal stem cells transfected with heme oxygenase-1 gene transplantation on ischemic Swine hearts].

OBJECTIVE: To observe the effect of intracoronary transfer of autologous HO-1 overexpressed MSCs in porcine model of myocardial ischemia (1 h)/reperfusion. METHODS: Apoptosis was assayed and cytokine concentrations in supernatant were measured in cells exposed to hypoxia-reoxygen in vitro. In vivo, Chinese male mini-pigs were allocated to the following treatment groups: control group (saline), MSCs group (MSCs), MSCs transfected with pcDNA3.1-nHO-1 (HO-1-MSCs). 1 x 10(7) of autologous stem cells or identical volume of saline was injected intracoronary into porcine hearts 1 h after ischemia. MRI assay and postmortem analysis were assessed 3 months after stem cell transplantation. RESULTS: In vitro, cell apoptosis rate post hypoxia-reoxygen was significantly reduced in HO-1-MSCs group (30.30% +/- 7.64%) compared with that in MSCs group (56.93% +/- 4.68%, P < 0.001) and LacZ-MSCs group (55.88% +/- 4.38%, P < 0.001), VEGF was also significantly upregulated in HO-1-MSCs group [(768.44 +/- 78.38) pg/ml] compared with that in MSCs group [(555.27 +/- 67.67) pg/ml, P < 0.001] and LacZ-MSCs group [(522.97 +/- 71.45) pg/ml, P < 0.001]. In vivo, cardiac function was significantly improved in both MSCs transplantation groups compared to saline group (all P < 0.05 vs.saline) and the left ventricular ejection fraction was significantly higher in HO-1-MSCs group compared with that in MSCs group at 3 months after transplantation (53.50% +/- 2.09% vs. 49.54% +/- 2.74%, P = 0.017), capillary density in the peri-infarct area was also significantly higher in HO-1-MSC group than that in MSCs group [(14.59 +/- 2.39)/HPF vs. (11.78 +/- 2.48)/HPF, P = 0.033]. CONCLUSIONS: Efficacy of HO-1 overexpressed MSCs on improving cardiac function and promoting angiogenesis was greater than those by MSCs in this porcine ischemia/reperfusion model.

Identification and differentiation of magnetically labeled mesenchymal stem cells in vivo in swines with myocardial infarction.

We aim to track mesenchymal stem cells (MSCs) after magnetically labeling and test the ability of these cells differentiate into cardiomyocytes in vivo. Therefore, 20 swines were divided into four groups, sham-operated group (n=3); acute myocardial infarction (AMI) transplanted with PBS (n=3); labeled MSCs (n=7) and unlabeled MSCs (n=7) group. 10(7) labeled or unlabeled cells were intracoronary delivered after MI (4.8+/-1.3 days), and serial cardiac MR (3.0T) imaging studies were performed at 0, 4 and 8 weeks after transplantation, then the results were confirmed by histological and western blot analysis. We demonstrated that labeled MSCs can be reliably detected and tracked in vivo using MR imaging. In particular, we provided the evidence of regeneration of labeled MSCs in vivo by histological examination and western blot analysis.

[Therapeutic effects of magnetically labeled mononuclear and mesenchymal stem cells transplantation in a swine myocardial infarction model assessed by magnetic resonance imaging].

OBJECTIVE: To evaluate the therapeutic effects of magnetically labeled mononuclear stem cells (MR-MNC) and mesenchymal stem cells (MR-MSC) transplantation in a swine acute myocardial infarction (AMI) model by MR imaging. METHODS: AMI model was established in swines by balloon occlusion of the left anterior descending coronary artery, 10(7) autologous MR-MSC (n = 7), MR-MNC (n = 6) or PBS (n = 6) were delivered via intracoronary infusion within 1 week after AMI [(4.8 +/- 1.3) days]. Changes of infarct size and cardiac function were assessed with the use of 3.0T MR scanner before AMI, at 1 and 8 weeks post AMI. RESULTS: Magnetically labeled stem cells could be identified in the region of AMI by cardiac MR imaging. Eight weeks post transplantation, infarct size was significantly reduced in MR-MSC transplantation group (8.5% +/- 0.5% vs. 24.7% +/- 3.1%, P < 0.05) and in MR-MNC transplantation (12.3% +/- 1.5% vs. 26.1% +/- 1.5%, P < 0.05) while infarct size remained unchanged in PBS group (P > 0.05) compared to values at 1 week post AMI, left ventricular ejection fraction (LVEF) was also significantly higher in MR-MSC transplantation group (56.9% +/- 1.3% vs. 40.7% +/- 2.0%, P < 0.05) and MR-MNC transplantation group (52.8% +/- 1.4% vs. 41.9% +/- 3.3%, P < 0.05) compared to LVEF at 1 week post AMI. LVEF increase was more significant in swines received MR-MSC transplantation than MR-MNC transplantation (16.2% +/- 1.2% vs. 10.9% +/- 3.0%, P < 0.05). Prussian blue staining identified stem cells in corresponding myocardial regions with as by MRI. Western blot analysis demonstrated that cardiac expressions of myosin heavy chain (MHC) in MR-MSC group (100.3 +/- 5.5) and in MR-MNCs group (95.5 +/- 4.2) were significantly higher than that in PBS group (75.7 +/- 5.7, P < 0.05), myocardial troponin T (cTNT) expression in MR-MSC group (124.0 +/- 5.8) and MR-MNC group (118.4 +/- 4.4) were also significantly higher than in PBS group (93.3 +/- 3.9, P < 0.05) while MMP2/TIMP1 ratios in MR-MSC group (0.6 +/- 0.1) and MR-MNC group (0.6 +/- 0.1) were significantly lower than that in PBS group (4.2 +/- 0.2, P < 0.05). CONCLUSIONS: Magnetically labeled MR-MSC and MR-MNC homed to heart post myocardial infarction and reduced infarct size, improved cardiac function. MR-MSC is superior to MR-MNC on improving cardiac function.

Transplantation of magnetically labeled mesenchymal stem cells improves cardiac function in a swine myocardial infarction model.

BACKGROUND: Mesenchymal stem cells (MSCs) transplantation provides a new approach for myocardial repair. However, many important fundamental questions about MSCs transplantation remain unanswered. There is an urgent need to identify MSCs from the beating heart and analyze the efficacy of this new approach. This study aimed to localize the magnetically labeled MSCs (MR-MSCs) and monitor the restorative effects of MR-MSCs with magnetic resonance (MR) imaging. METHODS: Acute myocardial infarction (AMI) was created in swine by a balloon occlusion of the left anterior descending coronary artery. Cells were delivered via intracoronary infusion after myocardial infarction. Infarct size change and cardiac function were assessed with 3.0T MR scanner. The results were then confirmed by histological and western blot analysis. All statistical procedures were performed with Systat (SPSS version 12.01). RESULTS: A total of 26 swine were divided into four groups (sham-operated group, n=6; AMI group with PBS transplantation, n=6; labeled MSCs group, n=7; unlabeled MSCs group, n=7). MSCs, MR-MSCs (10(7) cells) or PBS were delivered by intracoronary injection after MI and serial cardiac MR imaging studies were performed at 0, 4 and 8 weeks after transplantation. MR imaging demonstrated MI size decreased after MSCs transplantation in labeled and unlabeled groups, however, increases were seen in the AMI group at 8 weeks after MI. The left ventricular ejection fraction (LVEF) was slightly increased in the AMI group ((41.87+/-2.45)% vs (39.04+/-2.80)%, P>0.05), but significantly improved in the MR-MSCs group ((56.85+/-1.29)% vs (40.67+/-2.00)%, P<0.05) and unlabeled group ((55.38+/-1.07)% vs (41.78+/-2.08)%, P<0.05) at 8 weeks after treatment. MR-MSCs were further confirmed by Prussian blue and immunofluorescent staining. Western blot analysis demonstrated that there was an increased expression of cardiomyocyte markers such as myosin heavy chain and troponin T in the MSCs treatment groups and the ratio of matrix metalloproteinase 2 to tissue inhibitor of metalloproteinase 1 decreased in the labeled group and unlabeled group compared with the AMI group and sham-operated group. CONCLUSION: Transplanted MR-MSCs can regenerate new myocardium and prevent remolding in an MI model at 2-month follow-up and represent a preferred method to better understand the mechanisms of stem cell therapy in future clinical studies.