Abstract 145: Apelin Reduces Myocardial Infarction Size and Promotes Angiogenesis by Increasing SDF-1/CXCR4 and AKT/eNOS/VEGF Pathways

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Lanfang Li ◽  
Heng Zeng ◽  
Jian-xiong Chen

Background: Apelin is an endogenous ligand for the angiotensin-like 1 receptor (APJ) and is emerging as a key player in the regulation of angiogenesis as well as ischemia/reperfusion injury. So far, little is known about the functional role of apelin in myocardial ischemia. We investigated the potential intracellular molecular mechanisms and protective role of apelin during myocardial ischemic injury. Methods and Results: Myocardial ischemia was achieved by ligation of the left anterior descending coronary artery (LAD) for 24 hours and 14 days. Myocardial apoptosis was detected by TUNEL staining. Akt, endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), SDF-1 and CXCR4 expression were measured by western blot. The CD133+/cKit+/Sca1+, CD133/SDF-1+ and cKit/CXCR4+ cells were determined by immunostaining. Myocardial capillary and arteriole densities were analyzed in the border zone of infarcted myocardium at 14 d of ischemia. Treatment of C57BL/6J mice with apelin-13 (1 mg/Kg.d) by i.p. injection for 3 days before surgery results in significant decreases in TUNEL positive cells and myocardial infarct size at 24 hours of ischemia. Treatment with apelin increases the phosphorylation of AKT and eNOS and upregulates VEGF expression in the ischemic heart. Furthermore, treatment with apelin leads to the expression of SDF-1 and CXCR4 and increases in the number of CD133+/cKit+/Sca1+, CD133/SDF-1+ and cKit/CXCR4+ cells in ischemic hearts. Treatment with apelin also significantly increases myocardial capillary densities and arteriole formation together with a significant decrease in the ratio of heart weight to body weight at 14 days of ischemia. This is accompanied by a significant improvement of cardiac function after 14 days of ischemia. Conclusions: Our data demonstrate that apelin contributes to the protection of myocardial infarction and angiogenesis by the mechanisms involving in upregulation of SDF-1/CXCR4 and AKT/eNOS/VEGF pathways.

2016 ◽  
Vol 38 (4) ◽  
pp. 1365-1375 ◽  
Author(s):  
Jie Jian ◽  
Feifei Xuan ◽  
Feizhang Qin ◽  
Renbin Huang

Background/Aims: Previous studies have demonstrated that Bauhinia championii flavone (BCF) exhibits anti-oxidative, anti-hypoxic and anti-stress properties. This study was designed to investigate whether BCF has a cardioprotective effect against myocardial ischemia/reperfusion (I/R) injuries in rats and to shed light on its possible mechanism. Methods: The model of I/R was established by ligating the left anterior descending coronary artery for 30 min, then reperfusing for 180 min. Hemodynamic changes were continuously monitored. The content of malondialdehyde (MDA) as well as the lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were assessed. The release of interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay (ELISA). Apoptosis of cardiomyocytes was determined by caspase-3 activity and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The expression of TLR4, NF-κBp65, Bcl-2 and Bax were detected by western blotting. Results: Pretreatment with BCF significantly reduced the serum levels of LDH, MDA and IL-6, but increased the activities of SOD and GSH-Px. It also attenuated myocardial infarct size, reduced the apoptosis rate and preserved cardiac function. Furthermore, BCF inhibited caspase-3 activity and the expression of TLR4, phosphorylated NF-κBp65 and Bax, but enhanced the expression of Bcl-2. Conclusion: These results provide substantial evidence that BCF exerts a protective effect on myocardial I/R injury, which may be attributed to attenuating lipid peroxidation, the inflammatory response and apoptosis.


2021 ◽  
Vol 22 (9) ◽  
pp. 4401
Author(s):  
David Schumacher ◽  
Adelina Curaj ◽  
Mareike Staudt ◽  
Franziska Cordes ◽  
Andreea R. Dumitraşcu ◽  
...  

Phosphatidylserines are known to sustain skeletal muscle activity during intense activity or hypoxic conditions, as well as preserve neurocognitive function in older patients. Our previous studies pointed out a potential cardioprotective role of phosphatidylserine in heart ischemia. Therefore, we investigated the effects of phosphatidylserine oral supplementation in a mouse model of acute myocardial infarction (AMI). We found out that phosphatidylserine increases, significantly, the cardiomyocyte survival by 50% in an acute model of myocardial ischemia-reperfusion. Similar, phosphatidylserine reduced significantly the infarcted size by 30% and improved heart function by 25% in a chronic model of AMI. The main responsible mechanism seems to be up-regulation of protein kinase C epsilon (PKC-ε), the main player of cardio-protection during pre-conditioning. Interestingly, if the phosphatidylserine supplementation is started before induction of AMI, but not after, it selectively inhibits neutrophil’s activation, such as Interleukin 1 beta (IL-1β) expression, without affecting the healing and fibrosis. Thus, phosphatidylserine supplementation may represent a simple way to activate a pre-conditioning mechanism and may be a promising novel strategy to reduce infarct size following AMI and to prevent myocardial injury during myocardial infarction or cardiac surgery. Due to the minimal adverse effects, further investigation in large animals or in human are soon possible to establish the exact role of phosphatidylserine in cardiac diseases.


2008 ◽  
Vol 294 (6) ◽  
pp. H2547-H2557 ◽  
Author(s):  
Qin-hui Tuo ◽  
Heng Zeng ◽  
Amanda Stinnett ◽  
Heidi Yu ◽  
Judy L. Aschner ◽  
...  

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) are the two ligands of the Tie-2 receptor, a receptor tyrosine kinase that is expressed on the endothelium. A balanced angiopoietin/Tie-2 system is critical for the maintenance of vascular integrity. We investigated the potential role of a disrupted angiopoietin/Tie-2 system on hyperglycemic exacerbation of myocardial infarction and impaired angiogenesis. Using streptozotocin (STZ) mice subjected to myocardial ischemia, we examined the effects of shifting the Ang-2-to-Ang-1 ratio on myocardial infarction size, apoptosis, bone marrow (BM) cell-endothelial progenitor cell (EPC) differentiation, and angiogenesis. In control mice, myocardial ischemia increased expression of both Ang-2 and Tie-2. In STZ mice, Ang-2 expression was elevated, whereas Tie-2 expression was reduced, and neither was significantly altered by ischemia. Myocardial infarct size and apoptosis were increased in STZ compared with control mice. Using in vivo administration of an adenovirus containing Ang-1 or Ang-2, we found that shifting the Ang-2-to-Ang-1 ratio to favor Ang-1 reduced myocardial apoptosis and infarct size in STZ mice, while shifting the Ang-2-to-Ang-1 ratio to favor Ang-2 resulted in a significant increase in myocardial infarct size and apoptosis in control mice. Myocardial ischemia-stimulated BM cell-EPC differentiation was inhibited and myocardial angiogenesis was reduced in STZ mice. Systemic administration of Ad-Ang-1 restored BM cell-EPC differentiation and increased myocardial VEGF expression and angiogenesis in STZ mice. Our data demonstrate that disturbed angiopoietin/Tie-2 signaling contributes to the hyperglycemic exacerbation of myocardial infarction and impaired angiogenesis. Restoration of the Ang-2-to-Ang-1 ratio may be a novel therapeutic strategy for the treatment of diabetic myocardial ischemic diseases.


2019 ◽  
Vol 120 (01) ◽  
pp. 168-180 ◽  
Author(s):  
Alexander Akhmedov ◽  
Fabrizio Montecucco ◽  
Sarah Costantino ◽  
Daria Vdovenko ◽  
Ariane Schaub Clerigué ◽  
...  

AbstractIschemia/reperfusion (I/R) injury in acute myocardial infarction activates several deleterious molecular mechanisms. The transcription factor JunD regulates pathways involved in oxidative stress as well as in cellular proliferation, differentiation, and death. The present study investigated the potential role of JunD as a modulator of myocardial injury pathways in a mouse model of cardiac I/R injury. Infarct size, systemic and local inflammation, and production of reactive oxygen species, as well as cytosolic and mitochondrial apoptotic pathways were investigated in adult males after myocardial I/R. In wild-type (WT) mice, 30 minutes after ischemia and up to 24 hours following reperfusion, cardiac JunD messenger ribonucleic acid expression was reduced while JunB increased. Cardiac-specific JunD overexpressing mice (JunDTg/0 ) displayed larger infarcts compared with WT. However, postischemic inflammatory or oxidative responses did not differ. JunD overexpression reduced Sirt3 transcription by binding to its promoter, thus leading to mitochondrial dysfunction, myocardial cell death, and increased infarct size. On the other hand, JunD silencing reduced, while Sirt3 silencing increased infarct size. In human myocardial autopsy specimens, JunD-positive areas within the infarcted left ventricle staining corresponded to undetectable Sirt3 areas in consecutive sections of the same heart. Cardiac-specific JunD overexpression increases myocardial infarct size following I/R. These effects are mediated via Sirt3 transcriptional repression, mitochondrial swelling, and increased apoptosis, suggesting that JunD is a key regulator of myocardial I/R injury. The present data set the stage for further investigation of the potential role of Sirt3 activation as a novel target for the treatment of acute myocardial infarction.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Anindita das ◽  
Lei Xi ◽  
Fadi N Salloum ◽  
Yuan J Rao ◽  
Rakesh C Kukreja

Background: Sildenafil (SIL), a potent inhibitor of phosphodiesterase-5 induces powerful protection against myocardial ischemia-reperfusion (I-R) injury through activation of protein kinase G (PKG). However, the downstream targets of PKG in SIL-induced cardioprotection remain unclear. We hypothesized that PKG-dependent activation of survival kinase, ERK may play a critical role in SIL-induced cardioprotection in mice. Methods & Results: Ventricular myocytes were isolated from adult male ICR mice and exposed to 40 min of simulated ischemia (SI) with/without 1 hr pre-incubation of SIL (1 μM). Myocyte necrosis and apoptosis were determined after 1 hr or 18 hrs of reoxygenation (RO) using trypan blue or TUNEL assay, respectively. Pretreatment with SIL protected cardiomyocytes after SI-RO (necrosis 18.5±0.5% and apoptosis 6.6±0.7%; n=4, p<0.001) as compared with controls (necrosis 42.1±1.8% and apoptosis 23.3±0.9%). Co-incubation of PD98059 (20 μM), a selective ERK1/2 inhibitor blocked both anti-necrotic and anti-apoptotic protection in cardiomyocytes. Furthermore, intra-coronary infusion of SIL (1 μM) in Langendorff isolated mouse hearts 10 min prior to zero-flow global I (20 min) and R (30 min) significantly reduced myocardial infarct size (from 29.4±2.4% to 16.0±3.0%; p<0.05, n=6). Co-treatment of PD98059 abrogated SIL-induced protection (33.0±5.9; n=4). To evaluate the role of ERK1/2 in delayed cardioprotection, mice were treated with saline or SIL (0.7 mg/kg i.p.) 24 hours before global I-R in Langendorff mode. PD98059 (1 mg/kg) was administered (i.p.) 30 min before the treatment of SIL. Infarct size was reduced from 27.6±3.3% in saline-treated controls to 6.9±1.2% in SIL-treated mice (P<0.05, n=6). The delayed protective effect of SIL was also abolished by PD98059 (22.5±2.3%). Western Blots revealed that SIL significantly increased phosphorylation of ERK1/2 which was blocked by PKG inhibitor, KT5823 in the heart and adult myocytes. Selective knockdown of PKG in cardiomyocytes with short hairpin RNA of PKG also blocked the phosphorylation of ERK1/2. Conclusion: SIL-induced cardioprotection involves the activation and phosphorylation of ERK which appear to be intimately linked with a PKG-dependent survival pathway. This research has received full or partial funding support from the American Heart Association, AHA Mid-Atlantic Affiliate (Maryland, North Carolina, South Carolina, Virginia & Washington, DC).


2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Lichan Tao ◽  
Yihua Bei ◽  
Haifeng Zhang ◽  
Yanli Zhou ◽  
Jingfa Jiang ◽  
...  

Acute myocardial infarction (AMI) represents a major cause of morbidity and mortality worldwide. Exercise has been proved to reduce myocardial ischemia-reperfusion (I/R) injury. However it remains unclear whether, and (if so) how, exercise could protect against AMI. Methods: Mice were trained using a 3-week swimming protocol, and then subjected to left coronary artery (LCA) ligation, and finally sacrificed 24 h after AMI. Results: Exercise training reduces myocardial infarct size and abolishes AMI-induced autophagy and apoptosis. MI leads to a shift from fatty acid to glucose metabolism in the myocardium with a downregulation of PPAR-α and PPAR-γ. Also, AMI induces an adaptive increase of mitochondrial DNA replication and transcription in the acute phase of MI, accompanied by an activation of PGC-1α signaling. Exercise abolishes the derangement of myocardial glucose and lipid metabolism and further enhances the adaptive increase of mitochondrial biogenesis. Conclusion: Exercise training protects against AMI-induced acute cardiac injury through improving myocardial energy metabolism and enhancing the early adaptive change of mitochondrial biogenesis.


Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Chelsea Organ ◽  
Zhen Li ◽  
Yu Zhao ◽  
Chuntao Yang ◽  
Shashi Bhushan ◽  
...  

Background: Hydrogen sulfide (H2S) protects against acute myocardial ischemia/reperfusion (MI/R) injury and heart failure by ameliorating oxidative stress, improving mitochondrial function, and attenuating apoptosis. One of the major limitations of currently available H2S donors is poor pharmacokinetics profiles that result in very rapid and uncontrolled H2S release. NSHD-1 and NSHD-2 are recently developed thiol-activated H2S donors designed for sustained release of H2S upon activation by molecules containing thiol groups such as cysteine and glutathione. We hypothesized that these novel H2S donors would generate H2S for extended periods and ameliorate myocardial cell death following MI/R in an in vivo murine model. Methods and Results: C57BL6/J male mice (10-12 weeks of age) were subjected to 45 minutes of MI followed by 24 hours of R. At the time of reperfusion, animals received Vehicle (0.5% THF), NSHD-1 (50 μg/kg and 100 μg/kg), or NSHD-2 (50 μg/kg) by direct intracardiac (i.c.) injection. In addition, at 4 hours of R, plasma was collected for troponin-I measurements. In preliminary studies we observed sustained release of H2S with both of these H2S donors. Myocardial infarct size was reduced by 35% (p < 0.01 vs. Vehicle) in mice treated with NSHD-1 (100 μg/kg), 43% (p < 0.05 vs. Vehicle) in mice treated with NSHD-2 (50 μg/kg), and 54% (p < 0.01 vs. Vehicle) in mice treated with NSHD-2 (100 μg/kg). Conclusions: NSHD-1 and NSHD-2 significantly attenuate MI/R injury in a murine model. Experiments are currently underway to further define the in vivo pharmacokinetics of H2S release from these agents, mechanisms of action, and safety profile.


2020 ◽  
Vol 19 (5) ◽  
pp. 1031-1036
Author(s):  
Guixiang Zhao ◽  
Xiaoyun Ma ◽  
Juledezi Hailati ◽  
Zhen Bao ◽  
Maerjiaen Bakeyi ◽  
...  

Purpose: To determine the involvement of NLRP3 signaling pathway in the preventive role of daucosterol in acute myocardial infarction (AMI).Methods: H9C2 cells were pretreated with daucosterol before hypoxia/reoxygenation (HR) injury. Myocardial ischemia reperfusion (IR) was established in male SD rats, followed by reperfusion. Myocardial infarct size was measured. The serum levels of creatine kinase (CK), lactate  dehydrogenase (LDH), total superoxide dismutase (T-SOD), and malondialdehyde (MDA) were determined using commercial kits. NLRP3 inflammasome activation was assessed by western blotting.Results: Myocardial infarct size was smaller after IR injury in rats pretreated with daucosterol (10 and 50 mg/kg) than that pretreated with daucosterol (0 and 1 mg/kg). The increase in LDH, CK, and MDA levels after IR injury was reduced following daucosterol pretreatment. Reactive oxygen species (ROS) production increased, whereas T-SOD activity decreased after IR injury. These changes were prevented by pretreatment of daucosterol (10 and 50 mg/kg). Protein expression of NLRP3 inflammasome increased after IR injury in H9C2 cells while pretreatment with daucosterol inhibited the upregulation of NLRP3 inflammasome.Conclusion: The cardioprotective effect of daucosterol pretreatment appears to be mediated via the inactivation of ROS-related NLRP3 inflammasome, suggesting that daucosteol might be a potential therapeutic drug for AMI. Keywords: Daucosterol, Myocardial ischemia, Reperfusion injury, Reactive oxygen species, NLRP3 inflammasome


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Cheongsoo Park ◽  
Eun-Hye Park ◽  
Jongeun Kang ◽  
Javeria Zaheer ◽  
Hee Gu Lee ◽  
...  

We evaluated the relationship between myocardial infarct size and inflammatory response using cardiac magnetic resonance imaging (CMR) in an acute myocardial infarction (AMI) mouse model. Myocardial infarction (MI) was induced in 14 mice by permanent ligation of the left anterior descending artery. Late gadolinium enhancement (LGE), manganese-enhanced MRI (MEMRI), and magnetofluorescent nanoparticle MRI (MNP-MRI) were performed 1, 2, and 3 days after MI, respectively. The size of the enhanced lesion was quantitatively determined using Otsu’s thresholding method in area-based and sector-based approaches and was compared statistically. Linear correlation between the enhanced lesion sizes was evaluated by Pearson’s correlation coefficients. Differences were compared using Bland-Altman analysis. The size of the inflammatory area determined by MNP-MRI (57.1 ± 10.1%) was significantly larger than that of the infarct area measured by LGE (40.8 ± 11.7%, P<0.0001) and MEMRI (44.1 ± 14.9%, P<0.0001). There were significant correlations between the sizes of the infarct and inflammatory lesions (MNP-MRI versus LGE: r=0.3418, P=0.0099; MNP-MRI versus MEMRI: r=0.4764, P=0.0002). MNP-MRI provides information about inflammatory responses in a mouse model of AMI. Thus, MNP-MRI associated with LGE and MEMRI may play an important role in monitoring the disease progression in MI.


2020 ◽  
Author(s):  
Jianfeng Chen ◽  
Mingming Zhang ◽  
Shouyan Zhang ◽  
Junlong Wu ◽  
Shufeng Xue

Abstract Background: This study aimed to investigate the regulatory effect of rno-microRNA-30c-5p (rno-miR-30c-5p) on myocardial ischemia reperfusion (IR) injury in rats and the underlying molecular mechanisms.Methods: A rat model of myocardial IR injury was established. The infarct size was detected by 2,3,5-triphenyltetrazolium chloride staining. The pathologic changes of myocardial tissues were detected by hematoxylin-eosin staining. The apoptosis of myocardial cells was measured by TUNEL staining and flow cytometry. The mRNA expression of rno-miR-30c-5p and Sirtuin 1 (SIRT1) was detected by quantitative real-time PCR. The levels of IL-1β, IL-6 and TNF-α were detected by enzyme linked immunosorbent assay. The protein expression of Bax, Bcl-2, caspase-3, p-IκBα, IκBα, p-NF-κB p65, NF-κB p65 and SIRT1 was detected by Western blot. The interaction between rno-miR-30c-5p and SIRT1 was predicted by TargetScan, and further identified by dual luciferase reporter gene and RNA immunoprecipitation assay.Results: The myocardial IR injury model was successfully established in rats. IR induced the myocardial injury in rats and increased the expression of rno-miR-30c-5p. Overexpression of rno-miR-30c-5p enhanced the inflammation, promoted the apoptosis, and activated NF-κB pathway in IR myocardial cells. SIRT1 was the target gene of rno-miR-30c-5p. Silencing of SIRT1 reversed the effects of rno-miR-30c-5p inhibitor on the apoptosis and NF-κB pathway in IR myocardial cells.Conclusions: Rno-miR-30c-5p promoted the myocardial IR injury in rats through activating NF-κB pathway and down-regulating SIRT1.


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