scholarly journals Tongxinluo Attenuates Myocardiac Fibrosis after Acute Myocardial Infarction in Rats via Inhibition of Endothelial-to-Mesenchymal Transition

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Yujie Yin ◽  
Qian Zhang ◽  
Qifei Zhao ◽  
Guoyuan Ding ◽  
Cong Wei ◽  
...  

Endothelial-to-mesenchymal transition (EndMT) is an essential mechanism in myocardial fibrosis (MF). Tongxinluo (TXL) has been confirmed to protect the endothelium against reperfusion injury after acute myocardial infarction (AMI). However, whether TXL can inhibit MF after AMI via inhibiting EndMT remained unknown. This study aims to identify the role of EndMT in MF after AMI as well as the protective effects and underlying mechanisms of TXL on MF. The AMI model was established in rats by ligating left anterior descending coronary artery. Then, rats were administered with high- (0.8 g·kg−1·d−1), mid- (0.4 g·kg−1·d−1), and low- (0.2 g·kg−1·d−1) dose Tongxinluo and benazepril for 4 weeks, respectively. Cardiac function, infarct size, MF, and related indicators of EndMT were measured. In vitro, human cardiac microvascular endothelial cells (HCMECs) were pretreated with TXL for 4 h and then incubated in hypoxia conditions for 3 days to induce EndMT. Under this hypoxic condition, neuregulin-1 (NRG-1) siRNA were further applied to silence NRG-1 expression. Immunofluorescence microscopy was used to assess expression of endothelial marker of vWF and fibrotic marker of Vimentin. Related factors of EndMT were determined by Western blot analysis. TXL treatment significantly improved cardiac function, ameliorated MF, reduced collagen of fibrosis area (types I and III collagen) and limited excessive extracellular matrix deposition (mmp2 and mmp9). In addition, TXL inhibited EndMT in cardiac tissue and hypoxia-induced HCMECs. In hypoxia-induced HCMECs, TXL increased the expression of endothelial markers, whereas decreasing the expression of fibrotic markers, partially through enhanced expressions of NRG-1, phosphorylation of ErbB2, ErbB4, AKT, and downregulated expressions of hypoxia inducible factor-1a and transcription factor snail. After NRG-1 knockdown, the protective effect of TXL on HCMEC was partially abolished. In conclusion, TXL attenuates MF after AMI by inhibiting EndMT and through activating the NRG-1/ErbB- PI3K/AKT signalling cascade.

Author(s):  
Nada Joe Melhem ◽  
Mouna Chajadine ◽  
Ingrid Gomez ◽  
Kiave-Yune Howangyin ◽  
Marion Bouvet ◽  
...  

Background: Ischemic cardiovascular diseases, particularly acute myocardial infarction (MI) is one of the leading cause of mortality worldwide. Indoleamine 2, 3-dioxygenase 1 (IDO) catalyzes one rate-limiting step of L-Tryptophan (Trp) metabolism, and emerges as an important regulator of many pathological conditions. We hypothesized that IDO could play a key role to locally regulate cardiac homeostasis after MI. Methods: Cardiac repair was analyzed in mice harboring specific endothelial or smooth muscle cells or cardiomyocyte or myeloid cell deficiency of IDO and challenged with acute myocardial infarction. Results: We show that Kynurenine (Kyn) generation through IDO is markedly induced after MI in mice. Total genetic deletion or pharmacological inhibition of IDO limits cardiac injury and cardiac dysfunction after MI. Distinct loss of function of IDO in smooth muscle cells, inflammatory cells, or cardiomyocytes does not impact cardiac function and remodeling in infarcted mice. In sharp contrast, mice harboring endothelial cell-specific deletion of IDO show an improvement of cardiac function, as well as cardiomyocyte contractility and reduction in adverse ventricular remodeling. In vivo Kyn supplementation in IDO-deficient mice abrogates the protective effects of IDO deletion. Notably, Kyn precipitates cardiomyocyte apoptosis through reactive oxygen species production in an aryl hydrocarbon receptor-dependent mechanism. Conclusions: These data suggest that IDO could constitute a new therapeutic target during acute MI.


2021 ◽  
Author(s):  
Yize Sun ◽  
Zheyi Wang ◽  
Jiqiu Hou ◽  
Jinyu Shi ◽  
Zhuoran Tang ◽  
...  

Abstract Background Depression is a common complication of cardiovascular disease, which deteriorated the cardiac function. Shuangxinfang (Psycho-cardiology Formula, PCF) was reported to alleviate myocardial ischemia injury and improve depression-like behavior. Interestingly, our previous proteomics study predicted that the protein S100A9 appeared as an important target, and macrophage/microglial inflammation might be involved in the process of PCF treating depressive disorder induced by acute myocardial infarction (AMI). The aim of this study is to validate the proteomics results. Methods AMI rat models were established in vivo, followed by the administration of PCF or ABR-215757 (also named paquinimod, inhibiting S100A9 binding to TLR4) for 5 days. Forced swimming test (FST) and open field test (OFT) were applied to record depression-like behavior, and echocardiography was employed to evaluate cardiac function. Morphological changes of cardiomyocytes were assessed by HE staining and TUNEL staining on day 7 after cardiac surgery, as well as masson trichrome staining on day 21. Hippocampal neurogenesis was determined by Nissl staining, while 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor (BDNF) in the hippocampus were detected as biochemical indicators of depression. Myocardial and hippocampal expression of inflammatory factors were analyzed by western blotting, immunofluorescence, and ELISA. The activation state of macrophage and microglia was assessed via immunoreaction respectively using CD68 and Iba1. For in vitro confirmation, BV2 cells were primed with recombinant protein S100A9, and then pretreated with PCF serum, to determine alterations in microglial activation and inflammation. Results Rats in the AMI group showed heart function deterioration, as well as depression-like behavior. Coronary ligation not only brought about myocardial inflammation, cell apoptosis and fibrosis, but also reduced the neurogenesis and decreased the content of 5-HT. PCF could ameliorate the pathological and phenotypic changes of the heart and brain, and inhibited the expression of S100A9/TLR4/NF-κB pathway, the activation of microglial cell and the secretion of IL-1β and TNF-α raised by AMI. ABR-215757 showed therapeutic effect and molecular biological mechanisms similar to PCF. Pretreatment with PCF serum in vitro was proved to efficiently block the hyperactivation of BV2 cells and increasement of cytokine contents induced by recombinant protein S100A9. Conclusion We identify S100A9 as a novel and potent regulator of inflammation in both heart and brain. Macrophage/microglia inflammation mediated by S100A9 is considered as a pivotal pathogenic in depression post-AMI, as well as a major pathway for the treatment of PCF, suggesting that PCF is a promising therapeutic candidate for psycho-cardiology disease.


Author(s):  
Timur Yagudin ◽  
Yue Zhao ◽  
Haiyu Gao ◽  
Yang Zhang ◽  
Ying Yang ◽  
...  

Abstract Currently, there remains a great need to elucidate the molecular mechanism of acute myocardial infarction in order to facilitate the development of novel therapy. Inhibitor of apoptosis-stimulating protein of p53 (iASPP) is a member of the ASPP family proteins and an evolutionarily preserved inhibitor of p53 that is involved in many cellular processes, including apoptosis of cancer cells. The purpose of this study was to investigate the possible role of iASPP in acute myocardial infarction. The protein level of iASPP was markedly reduced in the ischemic hearts in vivo and hydrogen peroxide-exposed cardiomyocytes in vitro. Overexpression of iASPP reduced the infarct size and cardiomyocyte apoptosis of mice subjected to 24 h of coronary artery ligation. Echocardiography showed that cardiac function was improved as indicated by the increase in ejection fraction and fractional shortening. In contrast, knockdown of iASPP exacerbated cardiac injury as manifested by impaired cardiac function, increased infarct size, and apoptosis rate. Mechanistically, overexpression of iASPP inhibited, while knockdown of iASPP increased the expressions of p53 and Bax, the key regulators of apoptosis. Taken together, our results suggested that iASPP is an important regulator of cardiomyocyte apoptosis, which represents a potential target in the therapy of myocardial infarction.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Wen-wu Bai ◽  
Hao Wang ◽  
Chun-hua Gao ◽  
Ke-yin Liu ◽  
Bing-xiu Guo ◽  
...  

Acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide. Angiotensin (Ang) IV possesses many biological properties that are not yet completely understood. Therefore, we investigated the function and mechanism of Ang IV in AMI in in vivo and in vitro conditions. AMI was performed by ligation of the left anterior descending coronary artery (LAD) in male C57 mice. Ang IV was continuously infused by a minipump 3 d before AMI for 33 d. The neonatal rat ventricular myocytes (NRVCs) were stimulated with Ang IV and cultured under hypoxic conditions. In vivo, Ang IV infusion significantly reduced the mortality after AMI. By the 7th day after AMI, compared with the AMI group, Ang IV reduced the inflammatory cytokine expression. Moreover, terminal deoxyribonucleotidyl transferase- (TDT-) mediated dUTP nick-end labeling (TUNEL) assay showed that Ang IV infusion reduced AMI-induced cardiomyocyte apoptosis. Compared with AMI, Ang IV reduced autophagosomes in cardiomyocytes and improved mitochondrial swelling and disarrangement, as assessed by transmission electron microscopy. By 30th day after AMI, Ang IV significantly reduced the ratio of heart weight to body weight. Echocardiography showed that Ang IV improved impaired cardiac function. Hematoxylin and eosin (H&E) and Masson staining showed that Ang IV infusion reduced the infarction size and myocardial fibrosis. In vitro, dihydroethidium (DHE) staining and comet assay showed that, compared with the hypoxia group, Ang IV reduced oxidative stress and DNA damage. Enzyme-linked immunosorbent assay (ELISA) showed that Ang IV reduced hypoxia-induced secretion of the tumor necrosis factor- (TNF-) ɑ and interleukin- (IL-) 1β. In addition, compared with the hypoxia group, Ang IV reduced the transformation of light chain 3- (LC3-) I to LC3-II but increased p62 expression and decreased cardiomyocyte apoptosis. Overall, the present study showed that Ang IV reduced the inflammatory response, autophagy, and fibrosis after AMI, leading to reduced infarction size and improved cardiac function. Therefore, administration of Ang IV may be a feasible strategy for the treatment of AMI.


1989 ◽  
Vol 61 (03) ◽  
pp. 497-501 ◽  
Author(s):  
E Seifried ◽  
P Tanswell ◽  
D Ellbrück ◽  
W Haerer ◽  
A Schmidt

SummaryPharmacokinetics and systemic effects of recombinant tissue type plasminogen activator (rt-PA) were determined during coronary thrombolysis in 12 acute myocardial infarction patients using a consecutive intravenous infusion regimen. Ten mg rt-PA were infused in 2 minutes resulting in a peak plasma concentration (mean ±SD) of 3310±950 ng/ml, followed by 50 mg in 1 h and 30 mg in 1.5 h yielding steady state plasma levels of. 2210±470 nglml and 930±200 ng/ml, respectively. All patients received intravenous heparin. Total clearance of rt-PA was 380±74 ml/min, t,½α was 3.6±0.9 min and t,½β was 16±5.4 min.After 90 min, in plasma samples containing anti-rt-PA-IgG to inhibit in vitro effects, fibrinogen was decreased to 54%, plasminogen to 52%, α2-antiplasmin to 25%, α2-macroglobulin to 90% and antithrombin III to 85% of initial values. Coagulation times were prolonged and fibrin D-dimer concentrations increased from 0.40 to 2.7 μg/ml. It is concluded that pharmacokinetics of rt-PA show low interpatient variability and that its short mean residence time in plasma allows precise control of therapy. Apart from its moderate effect on the haemostatic system, rt-PA appears to lyse a fibrin pool in addition to the coronary thrombus.


Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2282
Author(s):  
Valentina Masola ◽  
Mario Bonomini ◽  
Maurizio Onisto ◽  
Pietro Manuel Ferraro ◽  
Arduino Arduini ◽  
...  

Glucose-based solutions remain the most used osmotic agents in peritoneal dialysis (PD), but unavoidably they contribute to the loss of peritoneal filtration capacity. Here, we evaluated at a molecular level the effects of XyloCore, a new PD solution with a low glucose content, in mesothelial and endothelial cells. Cell viability, integrity of mesothelial and endothelial cell membrane, activation of mesothelial and endothelial to mesenchymal transition programs, inflammation, and angiogenesis were evaluated by several techniques. Results showed that XyloCore preserves mesothelial and endothelial cell viability and membrane integrity. Moreover XyloCore, unlike glucose-based solutions, does not exert pro-fibrotic, -inflammatory, and -angiogenic effects. Overall, the in vitro evidence suggests that XyloCore could represent a potential biocompatible solution promising better outcomes in clinical practice.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Ondracek ◽  
T.M Hofbauer ◽  
A Mangold ◽  
T Scherz ◽  
V Seidl ◽  
...  

Abstract Introduction Leukocyte-mediated inflammation is crucial in acute myocardial infarction (AMI). We recently observed that neutrophil extracellular traps (NETs) are increased at the culprit site, promoting activation and differentiation of fibrocytes, cells with mesenchymal and leukocytic properties. Fibrocyte migration is mediated by monocyte chemoattractant protein (MCP)-1 and C-C chemokine receptor type 2 (CCR2). We investigated the interplay between NETs, fibrocyte function, and MCP-1 in AMI. Methods Culprit site and femoral blood of AMI patients was drawn during percutaneous coronary intervention. We characterized CCR2 expression of fibrocytes by flow cytometry. MCP-1 and the NET marker citrullinated histone H3 (citH3) were measured by ELISA. Fibrocytes were treated in vitro with MCP-1. Human coronary arterial endothelial cells (hCAECs) were stimulated with isolated NETs, and MCP-1 was measured by ELISA and qPCR. The influence of MCP-1 on NET formation in vitro was assessed using isolated neutrophils. Results We have included 50 consecutive AMI patients into the study. NETs and concentrations of MCP-1 were increased at the CLS. NET stimulation of hCAECs induced MCP-1 on mRNA and protein level. Increasing MCP-1 gradient was associated with fibrocyte accumulation at the site of occlusion. In the presence of higher MCP-1 these fibrocytes expressed proportionally less CCR2 than peripheral fibrocytes. In vitro, MCP-1 dose-dependently decreased fibrocyte CCR2 and reduced ex vivo NET release of healthy donor neutrophils. Conclusions NETs induce endothelial MCP-1 release, presumably promoting a chemotactic gradient for leukocyte and fibrocyte migration. MCP-1 mediated inhibition of NET formation could point to a negative feedback loop. These data will shed light on vascular healing. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Austrian Science Fund


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