Transcriptome Analysis of Myocardial Ischemic-Hypoxic Injury in Rats and Hypoxic H9C2 Cells.

AIMS: This study aimed to address inconsistencies in results between the H9C2 myocardial hypoxia (MH) cell line and myocardial infarction (MI) rat models used in MI research. We identified differentially expressed genes (DEGs) and underlying molecular mechanisms using RNA sequencing technology. METHODS: RNA sequencing was used to analyse DEGs in MI rat tissues and H9C2 cells exposed to hypoxia for 24 h. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to identify key biological processes and pathways. Weighted correlation network analysis [weighted gene co-expression network analysis (WGCNA)] was used to construct gene co-expression networks, and hub genes were compared with published MI datasets [Gene Expression Omnibus (GEO)] for target identification. RESULTS: GO analysis revealed enrichment of immune inflammation and mitochondrial respiration processes among 5139 DEGs in MI tissues and 2531 in H9C2 cells. KEGG analysis identified 537 overlapping genes associated with metabolism and oxidative stress pathways. Cross-analyses using the published GSE35088 and GSE47495 datasets identified 40 and 16 overlapping genes, respectively, with nine genes overlapping across all datasets and our models. WGCNA identified a key module in the MI model enriched for mRNA processing and protein binding. GO analysis revealed enrichment of mRNA processing, protein binding and mitochondrial respiratory chain complex I assembly in MI and H9C2 MH models. Five relevant hub genes were identified via a cross-analysis between the 92 hub genes that showed a common expression trend in both models. CONCLUSIONS: This study reveals both shared and distinct transcriptomic responses in the MI and H9C2 models, highlighting the importance of model selection for studying myocardial ischaemia and hypoxia.

Effect of miR-182-5p on apoptosis in myocardial infarction.

Objective: This study aimed to delineate the diagnostic significance of miR-182-5p by investigating its influence on myocardial apoptosis and function, employing both in vivo and in vitro myocardial infarction models. Methods: A rat myocardial infarction model was established. Myocardial infarction area was detected using the 2,3,5-chlorotriphenyltetrazolium (TTC) method, myocardial enzyme spectrums were measured using enzyme-linked immunosorbent assay (ELISA), myocardial structure was detected by hematoxylin and eosin (HE) staining, myocardial apoptosis was detected using the TUNEL method, and expression levels of miR-182-5p and apoptosis-related molecules were detected using real-time fluorescence quantitative PCR (qPCR) and Western blot. miR-182-5p mimics and inhibitor were transfected into rat H9C2 cardiomyocytes and mouse HL-1 cardiomyocytes to establish a hypoxia model. Cardiomyocyte viability was detected using the CCK-8 method, expression levels of apoptosis-related indicators were detected using Western blot, and caspase-3/7 activity was detected using a caspase-3/7 activity detection kit. AAV9 adeno-associated virus was used to construct an miR-182-5p overexpression virus, which was injected into mice through the tail vein to create a mouse myocardial infarction model. TTC, ELISA, HE staining, echocardiography, real-time fluorescence qPCR, and Western blot methods were used to detect the effects of AAV9-miR-182-5p on myocardial injury, myocardial function, and myocardial apoptosis levels in myocardial infarction. Results: The rat model displayed reduced miR-182-5p expression concurrent with an increase in apoptosis. The in vitro H9C2 and HL-1 hypoxia models revealed that miR-182-5p augmented the hypoxia-induced decrease in myocardial cell viability, suppressed Bcl-2 expression, and increased Bax, Bnip3, and caspase-3/7 activity levels. The injection of AAV9-miR-182-5p significantly exacerbated myocardial tissue damage, impaired myocardial function, and enhanced apoptosis. Conclusion: miR-182-5p escalates myocardial injury during myocardial infarction by fostering apoptosis. Interventions that aim to reduce miR-182-5p levels might be crucial in halting the progression of myocardial infarction.

Outcomes of catheter-directed thrombolysis versus systemic thrombolysis in the treatment of pulmonary embolism: a meta-analysis.

OBJECTIVE: To evaluate the safety and efficacy of catheter-directed thrombolysis (CDT) versus systemic thrombolysis (ST) in the treatment of pulmonary embolism (PE). METHODS: The Cochrane Library, PubMed, and Embase databases were searched to collect the literature on the comparison of the results of CDT and ST in the treatment of PE from the beginning of their records to May 2020, and meta-analysis was performed by STATA software (version 15.1). Using standardized data-collection forms, the authors screened the studies and independently extracted data, and assessed the quality of the studies using the Newcastle-Ottawa Scale for cohort studies. Cohort studies that examined the following results were included in the current study: in-hospital mortality, all-cause bleeding rate, gastrointestinal bleeding rate, intracranial hemorrhage rate, the incidence of shock, and hospital length of stay. RESULTS: A total of eight articles, with 13,242 participants, involving 3962 participants in the CDT group and 9280 participants in the ST group were included. CDT compared with ST in the treatment of PE can significantly affect in-hospital mortality rate [odds ratio (OR) = 0.41, 95% CI: 0.30-0.56, P < 0.05], all-cause bleeding rate (OR = 1.20, 95% CI: 1.04-1.39, P = 0.012), gastrointestinal bleeding rate (OR = 1.43, 95% CI: 1.13-1.81, P = 0.003), the incidence of shock (OR = 0.46, 95% CI: 0.37-0.57, P < 0.05), and hospital length of stay [standard mean difference (SMD) = 0.16, 95% CI: 0.07-0.25, P < 0.05]. However, there was no significant effect on intracranial hemorrhage rate in patients with PE (OR = 0.70, 95% CI: 0.47-1.03, P = 0.070). CONCLUSIONS: CDT is a viable alternative to ST in the treatment of PE, as it can significantly reduce in-hospital mortality rate, all-cause bleeding rate, gastrointestinal bleeding rate, and incidence of shock. However, CDT may prolong hospital length of stay to a certain extent. Further research is needed to evaluate the safety and efficacy of CDT and ST in the treatment of acute PE and other clinical outcomes.

Efficacy and safety of vena cava filters in preventing pulmonary embolism: A systematic review and meta-analysis.

OBJECTIVES: To assess the treatment effectiveness of inferior vena cava filters (IVCF) versus non-IVCF for patients undergoing varies conditions. METHODS: We systematically searched the databases to identify eligible RCTs from their inception up to 9/20/2020. The primary endpoint was pulmonary embolism (PE), while the secondary endpoints included deep-vein thrombosis (DVT), major bleeding, and all-cause mortality. The RRs with 95% CIs were applied as effect estimates for the treatment effectiveness of IVCF versus non-IVCF and calculated by using the random-effects model. RESULTS: 1,137 patients of 5 RCTs were enrolled. There were no significant differences between IVCF and non-IVCF for the risk of PE, major bleeding, and all-cause mortality, while the risk of DVT was significantly increased for patients treated with IVCF. CONCLUSIONS: The use of IVCF did not yield any benefits on PE, major bleeding, and all-cause mortality risk for patients undergoing various conditions, while the risk of DVT was significantly increased for patients treated with IVCF.

Association of obstructive sleep apnoea with long-term cardiovascular events in patients with acute coronary syndrome with or without hypertension: insight from the OSA-ACS project.

BACKGROUND: A close relationship exists between obstructive sleep apnoea (OSA) and hypertension. However, the impact of hypertension on the prognostic significance of OSA in patients with acute coronary syndrome (ACS) remains unclear. METHODS: This is a post hoc analysis of the OSA-ACS project, which consecutively included patients with ACS and receiving overnight sleep study from June 2015 to January 2020. OSA was defined as AHI ≥15 events/hour. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE), including a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularisation or hospitalisation for unstable angina or heart failure. RESULTS: A total of 1927 patients with ACS were finally enrolled in this study. The mean patient age was 56.4±10.5 years. Among them, 1247 (64.7%) patients had hypertension, and 1014 (52.6%) patients had OSA. During 2.9 (1.5, 3.6) years of follow-up, OSA was associated with an increased risk of MACCE among patients with hypertension (HR=1.35, 95% CI 1.04 to 1.75, p=0.02), but not in patients without hypertension (HR=1.15, 95% CI 0.79 to 1.68, p=0.47). The interaction between OSA and hypertension for MACCE was not statistically significant (interaction p=0.29). For patients with pre-existing hypertension, OSA was associated with an increased risk of MACCE only among those with grade 3 hypertension (HR 1.54, 95% CI 1.12 to 2.13, p=0.008), but not those with grade 1 or 2 hypertension. CONCLUSIONS: OSA was associated with an increased risk of MACCE following ACS in patients with hypertension, especially in patients with pre-existing severe hypertension. These findings highlight the importance of identifying OSA in ACS patients with hypertension. TRIAL REGISTRATION NUMBER: NCT03362385.

Expression of secreted frizzled-related proteins in acute aortic dissection patients and the effects on prognosis.

Background: Secreted frizzled-related proteins (SFRPs) were reported to be involved in cardiovascular diseases. This study aimed to observe plasma SFRP levels in acute aortic dissection (AD) patients and the effects of SFRP expression on AD prognosis. Methods: Plasma levels of SFRP1, SFRP2, SFRP3, SFRP4, and SFRP5 were measured in AD patients and non-AD (NAD) patients. The end-point events information of AD patients, including all-cause death and various clinical complications due to aortic dissection, was collected during a 36-month follow-up. Results: The SFRP1, SFRP2, SFRP3, and SFRP4 levels were increased in AD patients compared with those in NAD patients, while the SFRP5 concentrations were decreased. No differences in any of the SFRP levels were observed between the type A group and the type B group. The AD patients with end-point events exhibited higher SFRP1, SFRP2, SFRP3, and SFRP4 concentrations but lower SFRP5 levels than the patients without end-point events. In addition, the AD patients were divided into a high group and a low group based on the median SFRP levels, and Kaplan-Meier analysis revealed that the AD patients with high SFRP1, SFRP2, SFRP4, or SFRP5 levels had a better prognosis than those with low levels. However, the AD patients with high SFRP3 levels exhibited the opposite trends. The binary logistic regression analysis found that SFRP1, SFRP2, SFRP4, and SFRP5 were all negatively correlated with the occurrence of end-point events, while SFRP3 was positively correlated with its occurrence. Conclusions: SFRP levels are all changed in acute AD, which may affect the prognosis of AD patients. SFRPs may be a target to improve the prognosis of AD.

Air pollution increases the risk of pulmonary embolism: a meta-analysis.

OBJECTIVES: Air pollution can lead to many cardiovascular and respiratory diseases, but the impact of air pollution on pulmonary embolism is still uncertain. We conducted a meta-analysis to assess the relationship between air pollution and pulmonary embolism. CONTENT: We searched PubMed, EMBASE, Web of Science, and the Cochran Library for citations on air pollutants (carbon monoxide, sulfur dioxide, nitrogen dioxide, ozone and particulate matter) and pulmonary embolism. A total of nine citations met the inclusion criteria. There is no evidence of bias. CO, SO2, PM10 and PM2.5 had no significant effect on the occurrence of pulmonary embolism. NO2 and O3 can increase the risk of pulmonary embolism to a small extent. SUMMARY: This meta-analysis suggests that some air pollutants are associated with an increased risk of pulmonary embolism. OUTLOOK: Reducing air pollution and improving air quality can effectively reduce the risk of pulmonary embolism.

NR4A2 alleviates cardiomyocyte loss and myocardial injury in rats by transcriptionally suppressing CCR5 and inducing M2 polarization of macrophages.

BACKGROUND: CC chemokine receptor 5 (CCR5) has been demonstrated to be correlated to activation of pro-inflammatory immune cells and tissue injury. This study focused on the role of CCR5 in myocardial injury in rats with diabetic cardiomyopathy (DCM) and the mechanism of action. METHODS: A rat model of DCM was induced by streptozotocin (STZ). CCR5 was knocked down in rats to determine its role in myocardial injury and immune cell infiltration. The upstream regulators of CCR5 were bioinformatically predicted and the binding between nuclear receptor subfamily 4 group A member 2 (NR4A2) and CCR5 was validated. The portion of M1 and M2 macrophages in tissues was determined by flow cytometry or double-labeling immunofluorescence. Rat bone marrow mononuclear cells (BMMCs) were treated with granulocyte/macrophage colony stimulating factor (GM-CSF/M-CSF) and co-cultured with H9C2 cells for in vitro experiments. RESULTS: STZ-treated rats had impaired cardiac function and increased levels of creatine kinase-MB, cardiac troponin I and lactate dehydrogenase. CCR5 inhibition significantly alleviated myocardial injury in rats and reduced the portion of M1 macrophages in rat cardiac tissues. NR4A2, which could suppress CCR5 transcription, was poorly expressed in rats with DCM. NR4A2 overexpression played a similar myocardium-protective role in rats. In vitro, overexpression of NR4A2 induced M2 polarization of macrophages, which protected the co-cultured H9C2 cells from high glucose-induced damage, but the protective role was blocked after CCR5 overexpression. CONCLUSION: This study demonstrated that NR4A2 suppresses CCR5 expression and promotes M2 polarization of macrophages to alleviate cardiomyocyte loss and myocardial injury.

Effect of Shenfu Injection on Reperfusion Injury in Patients Undergoing Primary Percutaneous Coronary Intervention for ST Segment Elevation Myocardial Infarction: A Pilot Randomized Clinical Trial.

Background: Shenfu injection is a traditional Chinese medicine formulation that alleviates ischemia-reperfusion injury through multiple pharmacologic effects. However, no data are available regarding its efficacy in patients with myocardial infarction. We aimed to examine the effects of Shenfu injection on infarct size in patients with ST segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Methods: From April 2016 to February 2018, 40 patients with first-time anterior STEMI undergoing primary PCI within 6 h of symptom onset were randomized 1:1 to intravenous Shenfu injection (80 ml Shenfu injection + 70 ml 5% glucose injection) or placebo (150 ml 5% glucose injection) before reperfusion. Treatment started before PCI and maintained for 5 days after PCI. The primary end point was infarct size assessed by CK-MB area under the curve (AUC) over 72 h and cardiac magnetic resonance (CMR) imaging 4 ± 1 days after PCI. Results: Infarct size by area under the curve for CK-MB over 72 h did not differ between the Shenfu injection and placebo groups (5602.5 [3539.4-7526.4] vs. 6403.2 [2234.4-8340.6] ng·h/ml, P = 0.82). Among 32 patients who underwent CMR Imaging, a nominal reduction in infarct size was observed in the Shenfu injection group compared with the placebo group (23.9 [15.2-28.5] % vs. 27 [21.9-31.9] %, P = 0.42). After excluding patients with no or minimal infarct, there was a trend toward reduction in infarct size in the Shenfu injection group (24.1 [20.3-29.3] % vs. 29.1 [24.5-32] %, P = 0.18). Incidence of adverse events was similar between the groups. Conclusions: This pilot study showed that the use of Shenfu injection was safe but did not reduce infarct size by CMR Imaging and CK-MB release kinetics in reperfused patients with STEMI. Larger studies (confining to patients with extensive infarct size) to evaluate the efficacy of Shenfu injection on reperfusion injury are warranted. Clinical Trail Registration: clinicaltrials.gov, identifier: NCT02709798.

Circulating miRNAs Related to Long-term Adverse Cardiovascular Events in STEMI Patients: A Nested Case-Control Study.

BACKGROUND: Long-term morbidity and mortality of patients with ST-segment-elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PCI) remain substantial. Circulating microRNAs (miRNAs) play an important role in cardiovascular disease development. We aimed to identify circulating miRNAs associated with adverse cardiovascular events after acute myocardial infarction (AMI). METHODS: We performed a prospective, nested, case-control study of 932 patients with STEMI who underwent primary PCI. A 3-phase approach was conducted to screen candidate circulating miRNAs in 70 patients who subsequently experienced cardiac death, hospitalization for heart failure, or recurrent AMI (major adverse cardiovascular events [MACE] group) and in 140 patients matched for age, sex, time from symptom onset to blood collection and dual-antiplatelet therapy who did not report adverse cardiovascular events during 2-year follow-up (non-MACE group). RESULTS: We found that miR-26a-5p, miR-21-5p, and miR-191-5p levels were lower in the MACE group than in the non-MACE group (all P < 0.001). Multivariate conditional logistic regression analysis revealed that miR-26a-5p, miR-21-5p, and miR-191-5p levels were significantly inversely associated with incident primary composite outcomes (all adjusted P < 0.01). Importantly, the combination of these 3 miRNAs plus B-type natriuretic peptide clearly improved the risk scores recommended in the current guidelines, as determined with the use of C-statistics, net reclassification, and integrated discrimination. CONCLUSIONS: Our study provides proof-of-concept in humans that circulating miRNAs are associated with increased rates of distinct cardiovascular events, suggesting that they can serve as effective prognostic biomarkers and therapeutic targets for patients with AMI.

Thrombospondin-2 is upregulated in patients with aortic dissection and enhances angiotensin II-induced smooth muscle cell apoptosis.

Thrombospondin-2 (TSP-2) is an important extracellular matrix protein that is involved in a variety of cardiovascular diseases, including viral myocarditis and abdominal aortic aneurysm. The present study aimed to investigate TSP-2 expression in patients with aortic dissection (AD). Aortas were obtained from patients with AD and healthy donors, and TSP-2 expression level in all samples was measured by western blotting and immunofluorescence assays. Blood samples were also collected from patients with AD and non-AD (NAD) subjects. Circulating TSP-2, tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels in each sample were detected using ELISAs. In addition, the effect of TSP-2 on angiotensin II (Ang II)-induced smooth muscle cell (SMC) apoptosis was assessed in vitro. Compared with healthy donors, aortic TSP-2 expression level was significantly increased in patients with AD. Furthermore, TSP-2 was secreted primarily by SMCs, but also by endothelial cells. TSP-2 plasma expression level was also elevated in patients with AD compared with non-AD subjects. Furthermore, TSP-2 serum expression level was positively correlated with TNF-α and IL-6 expression levels in patients with AD. In addition, recombinant mouse TSP-2 treatment increased Bax mRNA expression and decreased Bcl2 mRNA expression in Ang II-treated SMCs; however, the effects were reversed following treatment with the NF-κB p65 signaling pathway inhibitor JSH-23 or with the anti-TNF-α and anti-IL-6 neutralizing antibodies. The present study demonstrated that TSP-2 expression was increased in the aortic tissues and plasma of patients with AD. These findings suggested that TSP-2 may participate in the progression of AD by activating the NF-κB p65 signaling pathway and amplifying the inflammatory response.

Galectin-3 and acute heart failure: genetic polymorphisms, plasma level, myocardial fibrosis and 1-year outcomes.

Aim: This study sought to investigate the relationship between galectin-3 (Gal-3), myocardial fibrosis (MF) and outcomes in acute heart failure. Materials & methods: The single-nucleotide polymorphisms (SNPs) of LGALS3 at rs4644 and rs4652, plasma Gal-3 level, MF and major adverse events (MAEs) were obtained. Results: There was no significant difference in MAEs when categorizing patients by the LGALS3 SNPs at rs4644 and rs4652. The circulating Gal-3 was related to the degree of MF (p < 0.001). Plasma Gal-3 level and MF can predict an increased risk of MAEs (p < 0.001, p = 0.023, respectively). Conclusion: Not the SNPs of LGALS3 but Gal-3 and MF can predict MAEs in acute heart failure at 1 year of follow-up.

IL-19 as a Biomarker for the Severity of Acute Myocardial Infarction.

BACKGROUND: Interleukin-19 (IL-19) has been shown to be involved in coronary artery diseases and atherosclerosis, while its expression in myocardial infarction is poorly understood. In this study, the dynamic increase in circulating IL-19 in acute ST-segment elevation myocardial infarction (STEMI) patients was detected. METHOD: Both plasma IL-19 levels and IL-19 mRNA expression in peripheral blood mononuclear cells (PBMCs) from STEMI patients and chest pain syndrome (CPS) patients were detected at different time points, including 1 d, 3 d, 7 d and 14 d after treatment and on admission. RESULTS: Compared with the CPS patients, IL-19 levels and IL-19 gene expression were significantly increased in STEMI patients and peaked at 1 d. From 1-14 d, refocusing treatment, including emergency percutaneous coronary intervention (PCI) and thrombolysis, markedly reduced IL-19 expression and promoted its recovery; of the treatments, the effect of emergency PCI was most significant. In addition, similar trends were also observed with cTnI, NT-proBNP and C-reactive protein (CRP) levels. Furthermore, correlation analysis showed that IL-19 levels were positively correlated with cTnI, NT-proBNP, CRP levels and left ventricular ejection fraction (LVEF) in STEMI patients. CONCLUSIONS: IL-19 is correlated with the severity of acute myocardial infarction, which may be a new idea for the clinical treatment of myocardial infarction.

Human epicardial adipose tissue-derived and circulating secreted frizzled-related protein 4 (SFRP4) levels are increased in patients with coronary artery disease.

BACKGROUND: Previous studies have demonstrated that secreted frizzled-related protein 4 (SFRP4) is associated with impaired glucose and triglyceride metabolism in patients with stable coronary artery disease. In the present study, we investigated human epicardial adipose tissue (EAT)-derived and circulating SFRP4 levels in patients with coronary artery disease (CAD). METHODS: Plasma samples and adipose biopsies from EAT and subcutaneous adipose tissue (SAT) were collected from patients with CAD (n = 40) and without CAD (non-CAD, n = 30) during elective cardiac surgery. The presence of CAD was identified by coronary angiography. SFRP4 mRNA and protein expression levels in adipose tissue were detected by quantitative real-time PCR and immunohistochemistry, respectively. Plasma SFRP4 concentrations were measured by an enzyme-linked immunosorbent assay (ELISA). Correlation analysis and multivariate linear regression analysis were used to determine the association of SFRP4 expression with atherosclerosis as well as clinical risk factors. RESULTS: SFRP4 mRNA and protein expression levels were significantly lower in EAT than in paired SAT in patients with and without CAD (all P < 0.05). Compared to non-CAD patients, CAD patients had higher SFRP4 expression levels in EAT (both mRNA and protein levels) and in plasma. Multivariate linear regression analysis showed that CAD was an independent predictor of SFRP4 expression levels in EAT (beta = 0.442, 95% CI 0.030-0.814; P = 0.036) and in plasma (beta = 0.300, 95% CI 0.056-0.545; P = 0.017). SAT-derived SFRP4 mRNA levels were independently associated with fasting insulin levels (beta = 0.382, 95% CI 0.008-0.756; P = 0.045). In addition, plasma SFRP4 levels were positively correlated with BMI (r = 0.259, P = 0.030), fasting insulin levels (r = 0.306, P = 0.010) and homeostasis model assessment of insulin resistance (HOMA-IR) values (r = 0.331, P = 0.005). CONCLUSIONS: EAT-derived and circulating SFRP4 expression levels were increased in patients with CAD. EAT SFRP4 mRNA levels and plasma SFRP4 concentrations were independently associated with the presence of CAD.

Triiodo-L-Thyronine Promotes the Maturation of Cardiomyocytes Derived From Rat Bone Marrow Mesenchymal Stem Cells.

Bone marrow mesenchymal stem cells (BMMSCs) can differentiate into cardiomyocytes and be used in cardiac tissue engineering for heart regeneration. However, the effective clinical application of cardiomyocytes derived from BMMSCs is limited because of their immature phenotype. The aim of this study was to investigate the potential of triiodo-L-thyronine (T3) to drive cardiomyocytes derived from BMMSCs to a more mature state. BMMSCs were divided into 3 groups: untreated controls, differentiated, and T3 treated. The differentiation potential was evaluated by immunofluorescence microscopy and flow cytometry. Data were represented as the numbers of cells positive for the troponin I (cTnI), α-actinin, GATA4, and the connexin-43 (Cx-43). The mRNA levels of these specific markers of cardiomyocytes were determined by quantitative real-time polymerase chain reaction. The levels of cardiomyocytes markers protein and octamer-binding transcription factor 4 (Oct-4) were determined by Western blot analyses. Our data demonstrate that T3 treatment leads to a significant increase in cells positive for cTnI, GATA4, Cx-43, and α-actinin. The mRNA and protein expression levels of these specific markers of cardiomyocytes were also increased after T3 treatment. At the same time, the protein expression level of Oct-4 was substantially downregulated in T3-treated cells. These results demonstrate that T3 treatment increases the differentiation of BMMSCs induced to cardiomyocytes and promotes their maturation.

Differentiation of Bone Marrow Mesenchymal Stem Cells to Cardiomyocyte-Like Cells Is Regulated by the Combined Low Dose Treatment of Transforming Growth Factor-ß1 and 5-Azacytidine.

Bone marrow mesenchymal stem cells (BMMSCs) are used in cardiac tissue engineering for the regeneration of diseased hearts. We examined the differentiation of rat BMMSCs into cardiomyocyte-like cells when induced with a combined low dose treatment of transforming growth factor-ß1 (TGF-ß1) and 5-azacytidine (5-AZA). Results showed that cell proliferation in the combined low dose treatment group of TGF-ß1 and 5-AZA was increased compared with the TGF-ß1 group or the 5-AZA group. The cell apoptosis was relieved by combined TGF-ß1 and 5-AZA treatment compared to 5-AZA treatment alone. The number of cells positive for myosin heavy chain, connexin-43, α-actin, and troponin I in the combined treatment group was higher than those observed in the TGF-ß1 group or the 5-AZA group. Moreover, the combined low dose treatment group of TGF-ß1 and 5-AZA reveals the strongest expression of troponin I, α-actin, and phosphorylated extracellular signal-regulated protein kinases 1 and 2 (p-ErK1/2) among the treatment groups. These results suggest that the combined low dose treatment of TGF-ß1 and 5-AZA can improve the differentiation potential of rat BMMSCs into cardiomyocyte-like cells and alleviate cell damage effects in vitro. The mechanism that is involved in influencing differentiation may be associated with p-ErK1/2.

Concomitant Retrograde Coronary Venous Infusion of Basic Fibroblast Growth Factor Enhances Engraftment and Differentiation of Bone Marrow Mesenchymal Stem Cells for Cardiac Repair after Myocardial Infarction.

AIM: Basic fibroblast growth factor (bFGF) increases the migration and viability of bone marrow mesenchymal stem cells (MSCs) in vitro. Retrograde coronary venous infusion can provide both increased regional bFGF concentrations and homogeneous cell dissemination. We determined whether retrograde delivery of bFGF enhances the potency of transplanted MSCs for cardiac repair in a canine infarct model. METHODS AND RESULTS: Under hypoxic conditions, cellular migration was significantly increased in MSCs co-cultured with bFGF compared to vascular endothelial growth factor or insulin-like growth factor, and bFGF promoted MSCs differentiation into a cardiomyocyte phenotype. A canine infarct model was employed by coronary ligation. One week later, animals were subjected to retrograde infusion of combination bFGF (200ng/mL) and MSCs (1×10(8) cells) (n=5), MSCs (1×10(8) cells, n=5), bFGF (200ng/mL, n=5), or placebo (phosphate-buffered saline, n=3). Four weeks after infusion, only the bFGF+MSCs therapy exhibited significantly increased left ventricular ejection fraction (LVEF) by echocardiography (p<0.01 vs pre-infusion), and the treatment effect (delta LVEF) was greater in the bFGF+MSCs group compared to saline (7.43±1.51% versus -10.07±2.94%; p<0.001). Morphologic analysis revealed an increased infarct wall thickness in the bFGF+MSCs group compared to all others (p<0.05), accompanied by increased vascular density and reduced apoptosis. Immunofluorescence demonstrated increased cell engraftment and enhanced vascular differentiation in the bFGF+MSCs group compared to MSCs alone (p<0.05). CONCLUSIONS: Retrograde coronary venous bFGF infusion augments engraftment and differentiation capacity of transplanted MSCs, recovering cardiac function and preventing adverse remodeling. This novel combined treatment and delivery method is a promising strategy for cardiac repair after ischemic injury.

Adaptive responses by mouse fetus to a maternal HLE diet by downregulating SREBP1: a microarray- and bio-analytic-based study.

Maternal diet has long been recognized as a significant factor affecting offspring development and health, but the target genes affected by a maternal high-lipid diet are currently unknown. In this study, the gene expression profile of neonatal mouse liver was analyzed using gene chips to identify genes with significant up- or downregulated expression levels due to maternal high-fat diet during gestation. Real-time PCR and Western blotting were used to measure key genes selected using microarray. Serum lipid, glucose, and insulin levels in adult offspring from dams fed with chow or a high-lipid diet were measured using commercial kits. Results indicate that the expression of genes involved in cholesterol and fatty acid synthesis were significantly inhibited, while the expression of genes involved in glycolysis were significantly decreased by maternal high-lipid diet during gestation. SREBP1 might be the key gene regulating genes involved in fatty acid, glucose, and cholesterol metabolism in response to a maternal high-fat diet.