Yachen Zhang

The lncRNA MALAT1 protects the endothelium against ox-LDL-induced dysfunction via upregulating the expression of the miR-22-3p target genes CXCR2 and AKT

CXCR2 plays a key role in protecting the integrity of the endothelium. Emerging evidence has demonstrated that the long ncRNAs (lncRNA) Human metastasis associated lung adenocarcinoma transcript 1 (MALAT1) participates in the regulation of the pathophysiological processes. However, whether there is crosstalk between CXCR2 and MALAT1 remains unknown. In this study, we demonstrated that MALAT1 was upregulated in patients with unstable angina. MALAT1 silencing significantly downregulated the expression of the miR‐22‐3p target gene CXCR2 via reversing the effect of the miR‐22‐3p, resulting in the aggravation of Oxidized low‐density lipoprotein (ox‐LDL)‐induced endothelial injury; this process was associated with the AKT pathway. Thus, MALAT1 protects the endothelium from ox‐LDL‐induced endothelial dysfunction partly through competing with miR‐22‐3p for endogenous RNA.

The role of miR-19b in the inhibition of endothelial cell apoptosis and its relationship with coronary artery disease

The biological effects of microRNAs (miRNAs) and TNF-α in atherosclerosis have been widely studied. The circulating miR-17-92 cluster has been recently shown to be significantly downregulated in patients with injured vascular endothelium. However, it remains unclear whether the miR-17-92 cluster plays a significant role in vascular endothelial repair. The aim of this study was to investigate the relationship between the miR-17-92 cluster and TNF-α-induced endothelial cell apoptosis. We determined that the down-regulation of miR-19b level among patients with coronary artery disease was consistent with miRNA expression changes in endothelial cells following 24 h of TNF-α treatment. In vitro, the overexpression of miR-19b significantly alleviated the endothelial cells apoptosis, whereas the inhibition of miR-19b significantly enhanced apoptosis. The increased levels of Afap1 and caspase7 observed in our apoptosis model could be reduced by miR-19b, and this effect could be due to miR-19b binding 3′-UTRs of Afap1 and caspase7 mRNA. Therefore our results indicate that miR-19b plays a key role in the attenuation of TNF-α-induced endothelial cell apoptosis and that this function is closely linked to the Apaf1/caspase-dependent pathway.

MALAT1 Modulates TGF-β1-Induced Endothelial-to-Mesenchymal Transition through Downregulation of miR-145

Background/Aims: Endothelial-to-mesenchymal transition (EndMT) plays significant roles under various pathological conditions including cardiovascular diseases, fibrosis, and cancer. EndMT of endothelial progenitor cells (EPCs) contributes to neointimal hyperplasia following cell therapy Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long non-coding RNA (lncRNA) that promotes metastasis and cancer. MicroRNA-145 (miR-145) is a tumor suppressor that has been reported to inhibit SMAD3-mediated epithelial-to-mesenchymal transition (EMT) of cancer cells. In the present study, we investigated the role of MALAT1 and miR-145 in EndMT of human circulating EPCs induced by transforming growth factor beta1 (TGF-β1). Methods: Human circulating EPCs were isolated and characterized by fluorescence-activated cell sorting (FACS). Expression levels of EndMT markers were assessed by qRT-PCR and western blotting. Alpha-smooth muscle actin (α-SMA) expression was measured by cell immunofluorescence staining. The regulatory relationship between MALAT1 and miR-145 and its target genes, TGFBR2 (TGFβ receptortype II) and SMAD3 (mothers against decapentaplegic homolog 3) was analyzed using the luciferase reporter assay. Results: We found that EndMT of EPCs induced by TGF-β1 is accompanied by increased MALAT1 expression and decreased miR-145 expression, and MALAT1 and miR-145 directly bind and reciprocally repress each other in these cells. Dual-Luciferase Reporter assay indicated that miR-145 inhibits TGF-β1-induced EndMT by directly targeting TGFBR2 and SMAD3. Conclusions: MALAT1 modulates TGF-β1-induced EndMT of EPCs through regulation of TGFBR2 and SMAD3 via miR-145. Thus, the MALAT1-miR-145-TGFBR2/SMAD3 signaling pathway plays a key role in TGF-β1-induced EndMT.

Long-term clinical efficacy and safety of adding cilostazol to dual antiplatelet therapy for patients undergoing PCI: a meta-analysis of randomized trials with adjusted indirect comparisons

Abstract Objective: To assess the long-term clinical efficacy and safety of adding cilostazol to aspirin plus clopidogrel (triple antiplatelet therapy, TAT) in patients undergoing percutaneous coronary intervention (PCI) and explore its role in the era of new generation adenosine diphosphate (ADP)-receptor antagonists. Methods: PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) comparing TAT versus dual antiplatelet therapy (DAT), followed by a manual search. Then, a meta-analysis of RCTs comparing TAT versus standard DAT in patients undergoing PCI was performed. Furthermore, indirect comparisons of TAT versus new generation ADP-receptor antagonist based DAT (prasugrel or ticagrelor based DAT) were undertaken, with standard DAT as a common comparator. The included end-points were major adverse cardiovascular event (MACE), target lesion revascularization (TLR), target vessel revascularization (TVR), death, myocardial infarction (MI), stent thrombosis, bleeding and other drug adverse events. Results: Twelve RCTs with a total of 31,789 patients were included. Compared with standard DAT (n = 2551), TAT (n = 2545) significantly reduced the incidence of MACE (OR: 0.56, 95% CI: 0.47–0.68, P < 0.00001), TLR (OR: 0.51, 95% CI: 0.34–0.75, P = 0.0006) and TVR (OR: 0.59, 95% CI: 0.46-0.75, P < 0.0001), and did not change significantly in death (OR: 0.68, 95% CI: 0.44–1.05, P = 0.08), MI (OR: 0.80, 95% CI: 0.45–1.44, P = 0.46), stent thrombosis (OR: 0.61, 95% CI: 0.27–1.36, P = 0.23), major bleeding (OR: 1.42, 95% CI: 0.52–3.85, P = 0.49) and overall bleeding (OR: 1.16, 95% CI: 0.79–1.69, P = 0.45). Compared with prasugrel (n = 6813) or ticagrelor based DAT (n = 6732), TAT (n = 2545) further reduced the incidence of MACE (OR: 0.80, 95% CI: 0.72–0.90, P = 0.0012; OR: 0.83, 95% CI: 0.75–0.92, P = 0.0003, respectively). Conclusions: Compared with standard DAT, the long-term use of TAT in patients with PCI gives more benefits in reducing the incidence of MACE, TLR and TVR without increasing bleeding. Furthermore, it might be superior to prasugrel or ticagrelor based DAT in term of MACE, which needs to be confirmed by future studies with direct comparisons.

A metabolomic study of rats with doxorubicin-induced cardiomyopathy and Shengmai injection treatment.

Doxorubicin-induced cardiomyopathy (DOX-CM) is a severe complication of doxorubicin (DOX) chemotherapy. Characterized by cumulative and irreversible myocardial damage, its pathogenesis has not been fully elucidated. Shengmai Injection (SMI), a Traditional Chinese Medicine, may alleviate myocardial injury and improve heart function in the setting of DOX-CM. As a result of its multi-component and multi-target nature and comprehensive regulation, the pharmacological mechanisms underlying SMI’s effects remain obscure. The emerging field of metabolomics provides a potential approach with which to explore the pathogenesis of DOX-CM and the benefits of SMI treatment. DOX-CM was induced in rats via intraperitoneal injections of DOX. Cardiac metabolic profiling was performed via gas chromatography/mass spectrometry and ultra-performance liquid chromatography/tandem mass spectrometry. A bioinformatics analysis was conducted via Ingenuity Pathway Analysis (IPA). Eight weeks following DOX treatment, significant cardiac remodeling, dysfunction and metabolic perturbations were observed in the rats with DOX-CM. The metabolic disturbances primarily involved lipids, amino acids, vitamins and energy metabolism, and may have been indicative of both an energy metabolism disorder and oxidative stress secondary to DOX chemotherapy. However, SMI improved cardiac structure and function, as well as the metabolism of the rats with DOX-CM. The metabolic alterations induced via SMI, including the promotion of glycogenolysis, glycolysis, amino acid utilization and antioxidation, suggested that SMI exerts cardioprotective effects by improving energy metabolism and attenuating oxidative stress. Moreover, the IPA revealed that important signaling molecules and enzymes interacted with the altered metabolites. These findings have provided us with new insights into the pathogenesis of DOX-CM and the effects of SMI, and suggest that the combination of metabolomic analysis and IPA may represent a promising tool with which to explore and better understand both heart disease and TCM therapy.

Role of the microRNA, miR-206, and its target PIK3C2α in endothelial progenitor cell function – potential link with coronary artery disease.

Coronary artery disease is a major cause of morbidity and mortality worldwide. Impaired endothelial function and integrity are major contributory factors to coronary artery disease. MicroRNAs have been proposed to play an important role in coronary artery disease pathogenesis. In the present study, the expression of miR‐206 was found to be significantly upregulated in peripheral blood endothelial progenitor cells from patients with coronary artery disease compared to healthy donors. MiR‐206 was found to regulate endothelial progenitor cell activities by targeting the protein kinase PIK3C2α, which showed decreased expression in coronary artery disease endothelial progenitor cells. Knockdown of miR‐206 in coronary artery disease endothelial progenitor cells rescued their angiogenic and vasculogenic abilities both in vitro and in vivo in a mouse ischemic hindlimb model. Furthermore, knockdown of miR‐206 activated not only PIK3C2α, but also the angiogenic signal modulators Akt and endothelial nitric oxide synthase. It is therefore proposed that repression of the phosphoinositide 3‐kinase/Akt/endothelial nitric oxide synthase signal transduction pathway by miR‐206 downregulates angiogenesis contributing to the pathophysiology of coronary artery disease.

Shengmai injection improved doxorubicin-induced cardiomyopathy by alleviating myocardial endoplasmic reticulum stress and caspase-12 dependent apoptosis.

Background. Apoptosis plays vital roles in the progression of doxorubicin-induced cardiomyopathy (DOX-CM). Endoplasmic reticulum stress (ER stress) could induce specific apoptosis by caspase-12 dependent pathway. Shengmai Injection (SMI), a famous Traditional Chinese Medicine, could alleviate the heart damage via inhibiting myocardial apoptosis. However, it is unknown whether SMI can alleviate ER stress and its specific apoptosis in the setting of DOX-CM. Objective. To explore the effects of SMI on heart function, myocardial ER stress, and apoptosis of DOX-CM rats. Methods. Rats with DOX-CM were treated by SMI. Heart function was assessed by echocardiography and brain natriuretic peptide. Myocardial apoptosis was detected by TUNEL assay. ER stress was assessed by detecting the expressions of GRP78 and caspase-12. Results. At the end of eight-week, compared to control, significant heart dysfunction happened in DOX group. The ratio of apoptotic cardiomyocytes and the expressions of GRP78 and caspase-12 increased significantly (P < 0.05). Compared to DOX group, the apoptotic ratio and the expressions of GRP78 and caspase-12 significantly decreased in DOX + SMI group (P < 0.05), accompanied with improved heart function. Conclusion. SMI could alleviate myocardial ER stress and caspase-12 dependent apoptosis, which subsequently helped to improve the heart function of rats with DOX-CM.

Ginsenoside Rg1 Protects Cardiomyocytes Against Hypoxia/Reoxygenation Injury via Activation of Nrf2/HO-1 Signaling and Inhibition of JNK

Background/Aims: Excessive reactive oxygen species (ROS) disturb the physiology of H9c2 cells, which is regarded as a major cause of H9c2 cardiomyocyte apoptosis. Ginsenoside Rg1 is the main active extract of ginseng, which has important antioxidant properties in various cell models. This project investigated the role of ginsenoside Rg1 in hypoxia/reoxygenation (H/R)-induced oxidative stress injury in cultured H9c2 cells to reveal the underlying signaling pathways. Methods: H9c2 cells were pretreated with ginsenoside Rg1 for 12 h before exposure to H/R. In the absence or presence of Nrf2siRNA, HO-1 inhibitor (ZnPP-IX), and inhibitors of the MAPK pathway (SB203580, PD98059, SP600125), H9c2 cells were subjected to H/R with Rg1 treatment. The effects and mechanisms of H/R-induced cardiomyocyte injury were measured. Results: Ginsenoside Rg1 treatment suppressed H/R-induced apoptosis and caspase-3 activation. Ginsenoside Rg1 treatment decreased ROS production and mitochondrial membrane depolarization by elevating the intracellular antioxidant capacity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and reduced glutathione (GSH). Furthermore, ginsenoside Rg1 stimulation appeared to result in nuclear translocation of NF-E2-related factor 2 (Nrf2), along with enhanced expression of the downstream target gene heme oxygenase-1 (HO-1) in a dose-dependent manner. However, ginsenoside Rg1-mediated cardioprotection was abolished by Nrf2-siRNA and HO-1 inhibitor. H/R treatment increased the levels of phosphorylated c-Jun N-terminal kinases (p-JNK), which was dramatically attenuated by ginsenoside Rg1 and SP600125 (a specific JNK inhibitor). Conclusion: These observations indicate that ginsenoside Rg1 activates the Nrf2/HO-1 axis and inhibits the JNK pathway in H9c2 cells to protect against oxidative stress.

A Phase Compensation Method for Phase Extraction of Abrupt Surfaces in Projection Moiré

Projection moiré method is a high-resolution, non-contacting and full-field optical measurement technique. But the 2π-ambiguity problem in phase unwrapping limits the phase difference between neighbouring pixels under π which makes projection moiré method ineffective at measuring abrupt surfaces or steps. This paper aims at putting forward a phase compensation method to solve this 2π-ambiguity problem in projection moiré. Since the phase of moiré pattern is the variance between the phase of specimen grating on object’s surface and the phase of the reference grating, our method is to calculate the phases of specimen grating and the reference grating respectively, regard their difference as the phase of the moiré pattern in theory and correct the wrong unwrapped moiré fringe phase with integral multiple of 2π. In order to acquire the phase of specimen grating which also has the 2π-ambiguity problem, using multiple fringe pictures with different pitches. The experiments successfully reconstruct two objects with discontinuities in their surfaces. This phase compensation technique no longer requires us to count fringe orders or find a reference point to mark the zero-order moiré fringe during experiments.

Fosinopril Attenuates the Doxorubicin-induced Cardiomyopathy by Restoring the Function of Sarcoplasmic Reticulum

Fosinopril, an angiotensin-converting enzyme inhibitor, is known to attenuate cardiomyopathy induced by doxorubicin (DOX); however, the mechanisms of this cardioprotection are not fully elucidated yet. In the present study, experimental cardiomyopathy was induced in rats by administration of DOX with or without co-treatment with fosinopril. Fosinopril was utilized on day 1 or 14 of the treatment with DOX to compare efficacies of early versus late co-treatments. We observed that fosinopril attenuated changes induced by DOX (e.g., less increased heart and left ventricular weights, diminished lung congestion and ascites, attenuated LVEDP and LVSP, and less decreased +dP/dt and −dP/dt). Further, fosinopril diminished the levels of markers of cardiac toxicity (i.e., plasma levels and activities of cardiac enzymes and proteins AST, LDH, CPK, cTnI, and BNP). Fosinopril also prevented DOX-induced decreases in Ca2+ uptake and restored activity of Ca2+-stimulated ATPase in left ventricular sarcoplasmic reticulum. We next tested whether the improved Ca2+ transport activity in sarcoplasmic reticulum was due to modulation of SERCA2 and phospholamban expressions by fosinopril. Fosinopril attenuated the decrease in SERCA2 and phospholamban expressions caused by DOX. In conclusion, cardioprotective effects of fosinopril in the DOX-induced cardiomyopathy appear to be due to its ability to prevent remodeling of the cardiac sarcoplasmic reticulum membrane.