scholarly journals RRM2 Improves Cardiomyocyte Proliferation after Myocardial Ischemia Reperfusion Injury through the Hippo-YAP Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Huamin Yu ◽  
Haiyan Tang ◽  
Chaochao Deng ◽  
Qing Lin ◽  
Peng Yu ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Neonatal Rat ◽  
Cell Counting ◽  
Cardiomyocyte Proliferation ◽  
Rat Cardiomyocytes ◽  
Qrt Pcr ◽  
Myocardial Ischemia Reperfusion ◽  
Deoxyribonucleoside Triphosphate

Objective. Ribonucleotide reductase M2 (RRM2) as an enzyme that catalyzes the deoxyreduction of nucleosides to deoxyribonucleoside triphosphate (dNTP) has been extensively studied, and it plays a crucial role in regulating cell proliferation. However, its role in ischemia-reperfusion injury (I/RI) is still unclear. Methods. SD rats were used as the research object to detect the expression of RRM2 in the myocardium by constructing an I/RI model. At the same time, primary SD neonatal rat cardiomyocytes were extracted, and hypoxia/reoxygenation (H/R) treatment simulated the I/RI model. Using transfection technology to overexpress RRM2 in cardiomyocytes, quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of RRM2, Cell Counting Kit-8 (CCK-8) assay was used to detect cell viability, and immunofluorescence staining was used to detect Ki67 and EdU-positive cells. Western blot (WB) technology was used to detect YAP and its phosphorylation expression. Results. qRT-PCR results indicated that the expression of RRM2 was inhibited in the model group, and cardiomyocytes overexpressing RRM2 can obviously promote the proliferation of primary cardiomyocytes and improve the damage of cardiac structure and function caused by I/R. At the same time, RRM2 can promote the increase of YAP protein expression and the increase of Cyclin D1 mRNA expression. Conclusion. RRM2 expression was downregulated in myocardial tissue with I/R. After overexpression of RRM2, cardiomyocyte proliferation was upregulated and the Hippo-YAP signaling pathway was activated.

scholarly journals Follistatin-Like 1 Attenuates Ischemia/Reperfusion Injury in Cardiomyocytes via Regulation of Autophagy

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Weijun Yang ◽  
Qunjun Duan ◽  
Xian Zhu ◽  
Kaiyu Tao ◽  
Aiqiang Dong
Keyword(s):  
Cell Viability ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Annexin V ◽  
Protective Role ◽  
Autophagic Flux ◽  
Rat Cardiomyocytes ◽  
Hypoxia Ischemia ◽  
Myocardial Ischemia Reperfusion

Background. The cardioprotective effect of FSTL1 has been extensively studied in recent years, but its role in myocardial ischemia/reperfusion injury (IRI) is unclear. In this study, we investigated the effect of FSTL1 pretreatment on myocardial IRI as well as the possible involvement of autophagic pathways in its effects. Methods. The effects of FSTL1 on the viability and apoptosis of rat cardiomyocytes were investigated after exposure of cardiomyocytes to hypoxia/ischemia by using the CCK-8 assay and Annexin V/PI staining. Further, western blot analysis was used to detect the effects of FSTL1 pretreatment on autophagy-associated proteins, and confocal microscopy was used to observe autophagic flux. To confirm the role of autophagy, the cells were treated with the autophagy promoter rapamycin or the autophagy inhibitor 3-methyladenine, and cell viability and apoptosis during IRI were observed. These effects were also observed after treatment with rapamycin or 3-methyladenine followed by FSTL1 administration and IRI. Results. FSTL1 pretreatment significantly increased viability and reduced apoptosis in cardiomyocytes exposed to hypoxia/ischemia conditions. Further, FSTL1 pretreatment affected the levels of the autophagy-related proteins and enhanced autophagic flux during IRI. In addition, cell viability was enhanced and apoptosis was decreased by rapamycin treatment, while these effects were reversed by 3-MA treatment. However, when the myocardial cells were pretreated with rapamycin or 3-methyladenine, there was no significant change in their viability or apoptosis with FSTL1 treatment during IRI. Conclusions. FSTL1 plays a protective role in myocardial IRI by regulating autophagy.

Abstract 354: Prostaglandin D 2 -F Type Prostanoid Receptor Signaling Is a Novel Cardiomyocyte Survival Pathway

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Yoshinori Katsumata ◽  
Motoaki Sano ◽  
Tomohiro Matsuhashi ◽  
Atsushi Anzai ◽  
Cardex Yan ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Expression Profiles ◽  
Ischemia Reperfusion ◽  
Cardioprotective Effect ◽  
Neonatal Rat ◽  
Th2 Cells ◽  
Dependent Manner ◽  
Rat Cardiomyocytes ◽  
Fp Receptor

Background: Lipocalin-type prostaglandin D synthase (L-PGDS) is abundantly expressed on cardiomyocytes. We recently demonstrated that dexamethasone stimulates PGD 2 -dominated activation of prostanoid biosynthesis, thereby protecting hearts against ischemia/reperfusion injury. Here, we examined the downstream signaling responsible for cardioprotection mediated through PGD 2 -dominated activation. Methods and Results: (1) In cultured neonatal rat cardiomyocytes, PGD 2 strongly activates ERK in a dose-dependent manner, although canonical PGD 2 receptors, including DP (PGD 2 receptor) and CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells) receptors, are hardly expressed on cardiomyocytes. (2) Interestingly, PGD 2 bounds to FP receptor (the canonical PGF 2 α receptor) with an affinity comparable to that for the DP receptor, and the FP receptor is abundantly expressed on cardiomyocytes. (3) PGD 2 -induced ERK activation is completely blocked by FP antagonist or siRNA-mediated knockdown of the FP, but not by DP and CRTH2 antagonist and siRNA-mediated knockdown of DP and CRTH2. (4) PGD 2 activates ERK in Langendorff perfused DP-knock out (KO) and CRTH2-KO mice hearts to comparable levels as those observed for wild-type hearts, while cannot activate it in FP-KO hearts. (5) Consistently, the cardioprotective effect of PGD 2 -dominated activation by dexamethasone was blunted in FP KO hearts. (6) Furtermore, genomewide gene expression profiles by microarray analysis and quantitative real-time RT-PCR analysis identified that Nrf-2 was the downstream target of L-PGDS-mediated PGD 2 biosynthesis. (7) In cultured cardiomyocytes, FP agonist stimulated Nrf2 nuclear translocation and consequently induced Nrf2-target genes expression in an ERK-dependent manner. (8) Finally, The cardioprotective effect by dexamethasone was completely abolished in Nrf-2 KO hearts. Conclusion: FP serves as a functionally relevant PGD 2 receptor in the hearts and PGD 2 -FP signaling plays a substantial role in the improvement of functional recovery after ischemia-reperfusion injury in the heart. Nrf-2 is a major effector molecule responsible for the cardioprotecton elicited by L-PGDS-derived PGD 2 .

Resveratrol Nanoparticle Complex: Potential Therapeutic Applications in Myocardial Ischemia Reperfusion Injury

2020 ◽  
Vol 16 (3) ◽  
pp. 382-389
Author(s):  
Hong Zhou ◽  
Yungang Shan ◽  
Fei Tong ◽  
Yi Zhang ◽  
Jie Tang ◽  
...  
Keyword(s):  
Myocardial Ischemia ◽  
Reperfusion Injury ◽  
Half Life ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Proton Nuclear Magnetic Resonance ◽  
Release Time ◽  
Rat Cardiomyocytes ◽  
Myocardial Ischemia Reperfusion Injury ◽  
Myocardial Ischemia Reperfusion

Resveratrol (RES) is a natural non-flavonoid polyphenol with cardioprotective activities, antioxidant, antiplatelet, and antiinflammatory. However, its low aqueous solubility, chemical stability, and oral bioavailability, as well as a short circulation half-life greatly limit its clinical applications. To overcome these limitations of RES, we synthesized a methoxy poly(ethylene glycol)-b-oligomerization(D, L-Leucine) (mPEG-b-O(D, L-Leu)) nanoparticle (NP) as the carrier of RES and evaluated the myocardial-protective effectiveness of this RES/NP complex in rat myocardial ischemia-reperfusion injury models. We gauged the characterization of the NP through proton nuclear magnetic resonance spectroscopy, gel permeation chromatography, transmission electron microscope, and Fourier transform infrared spectroscopy and then loaded RES on the nanocarrier by hydrophobic interactions under physiological pH to extend the release time of RES and prolong its circulation half-life. Subsequently, we used rat cardiomyocytes (H9C2 cells) and rat MI/RI model to investigate the relationship between drug composition and myocardial preservation properties. It was found that RES was encapsulated quickly and efficiently, and displayed an effectual loading-capacity and in vitro sustained-release. Anti-MI/RI effect of the RES/NP complex was found satisfactory in rat models in vivo using free RES as the control. This study suggested that NP may prove to be a potent nanocarrier to augment the pharmacotherapy of RES against MI/RI.

MicroRNA-34a protects myocardial cells against ischemia–reperfusion injury through inhibiting autophagy via regulating TNFα expression

2018 ◽  
Vol 96 (3) ◽  
pp. 349-354 ◽  
Author(s):  
Haifeng Shao ◽  
Lili Yang ◽  
Li Wang ◽  
Bozan Tang ◽  
Jian Wang ◽  
...  
Keyword(s):  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Heart Tissue ◽  
Neonatal Rat ◽  
Cell Counting ◽  
In Vivo Model ◽  
Myocardial Cells ◽  
Rat Cardiomyocytes ◽  
Cardiac Tissues

Background: ischemia–reperfusion (I/R) is a consequence of restored blood supply after myocardial infarction. Myocardial I/R injury can be alleviated by reducing autophagy in heart tissue. MicroRNA-34a (miR-34a) has been shown to regulate autophagy in a renal model of I/R, but it is not known whether it can protect cardiac tissues from I/R injury. This study investigated how miR-34a protects myocardial cells from I/R injury by inhibiting autophagy via regulation of tumor necrosis factor α (TNFα). Methods: we constructed an I/R model in vivo using Langendorff perfusion, and we constructed an in vivo model by treating neonatal rat cardiomyocytes (NRCMs) with hypoxia–reoxygenation (H/R method). Transfected adenoviral-overexpressed miR-34a mimics and controlled NRCMs after H/R. We analyzed cell viability using the MTT assay and a cell counting kit-8 (CCK-8) assay. Changes in the rate of apoptosis were detected by flow cytometry. We investigated the effect mechanisms of miR-34a with Western blot and luciferase assays. Results: miR-34a expression decreased after in vivo reperfusion of the myocardial cells and heart tissues of neonatal rats. MiR-34a reduced apoptosis of the NRCMs and autophagy levels, simultaneously, after H/R injury. Further, miR-34a decreased the expression of Lc3-II and p62, indicating that miR-34a reduces myocardial I/R injury by decreasing TNFα expression. Conclusion: miR-34a can inhibit autophagy levels after I/R by targeting TNFα, thereby reducing myocardial injury.

scholarly journals CircANXA2 Promotes Myocardial Apoptosis in Myocardial Ischemia-Reperfusion Injury via Inhibiting miRNA-133 Expression

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Liang Zong ◽  
Weixin Wang
Keyword(s):  
Myocardial Ischemia ◽  
Western Blot ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Cardiomyocyte Apoptosis ◽  
H9c2 Cells ◽  
Qrt Pcr ◽  
Myocardial Ischemia Reperfusion Injury ◽  
Myocardial Ischemia Reperfusion

Objective. This project is aimed at investigating whether CircANXA2 can promote the apoptosis of myocardial cells by inhibiting miR-133 expression and thereby participate in the development of myocardial ischemia-reperfusion injury. Materials and Method. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression level of CircANXA2 in H9c2 cells after hypoxia/reoxygenation (H/R) treatment. Evaluation of myocardial injury markers in H9c2 cells was performed using commercial kits, including lactate dehydrogenase (LDH), malonaldehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidation (GSH-PX). MTT analysis and flow cytometry were used to detect myocardial cell proliferation and apoptosis, respectively. Western blot was used to detect the protein expression of apoptosis-related genes. Result. qRT-PCR results showed that compared with the control, the expression of CircANXA2 was upregulated and the expression level of miR-133 was significantly decreased in H/R-treated H9c2 cells. CircANXA2 overexpression increased LDH, MDA, SOD, and GSH-PX activity in H/R-treated H9c2 cells. At the same time, CircANXA2 overexpression inhibited the proliferation of H/R-treated cells, and CircANXA2 was able to induce cardiomyocyte apoptosis. Western blot results showed that after overexpression of CircANXA2, the proapoptotic genes Bax and cytochrome C was upregulated, while the antiapoptotic gene Bcl-2 was downregulated. In H9c2 cells, upregulating miR-133 can reverse the inhibition of proliferation induced by CircANXA2 overexpression and increase apoptosis. Conclusions. CircANXA2 promotes cardiomyocyte apoptosis in myocardial ischemia-reperfusion injury by inhibiting the expression of miR-133. CircANXA2 may be a potential target for myocardial ischemia-reperfusion injury.

scholarly journals Simvastatin Improves Myocardial Ischemia Reperfusion Injury through KLF-Regulated Alleviation of Inflammation

2022 ◽  
Vol 2022 ◽  
pp. 1-6
Author(s):  
Tingju Wei ◽  
Jun Li ◽  
Guowei Fu ◽  
Hui Zhao ◽  
Chen Huang ◽  
...  
Keyword(s):  
Myocardial Ischemia ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Male Rats ◽  
Cell Counting ◽  
Inflammatory Factors ◽  
Simvastatin Treatment ◽  
Myocardial Ischemia Reperfusion Injury ◽  
Myocardial Ischemia Reperfusion

Objective. To clarify the protective effect of simvastatin on myocardial ischemia reperfusion injury (MIRI) and the underlying mechanism. Materials and Methods. The MIRI model in rats was firstly constructed. Twenty-four male rats were randomly assigned into the sham group, ischemia-reperfusion (I/R) group, and simvastatin group, with 8 rats in each group. Contents of superoxide dismutase (SOD) and malondialdehyde (MDA), as well as serum levels of CK and inflammatory factors, in rats were determined by the enzyme-linked immunosorbent assay (ELISA). Lactate dehydrogenase (LDH) activity in the three groups was examined. Through flow cytometry and Cell Counting Kit-8 (CCK-8) assay, apoptosis and viability in each group were detected, respectively. Relative levels of HMGB1, Kruppel-like factor 2 (KLF2), eNOS, and thrombomodulin (TM) were finally determined. Results. Simvastatin treatment markedly enhanced SOD activity and reduced contents of MDA, LDH, and creatine kinase (CK) in MIRI rats. The increased apoptosis and decreased viability following MIRI were partially reversed by simvastatin treatment. Besides, MIRI resulted in the upregulation of inflammatory factors and chemokines. Their elevations were abolished by simvastatin. In MIRI rats, simvastatin upregulated KLF2 and p-eNOS. Conclusions. Simvastatin protects inflammatory response at post-MIRI through upregulating KLF2, thus improving cardiac function.

Abstract P451: Depletion Of Rbl2 Exacerbates Cardiomyocyte Apoptosis And Ischemia-reperfusion Injury By Augmenting E2f1-mediated Bnip3 Expression

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Jingrui Chen ◽  
Yuening Liu ◽  
Peng Xia ◽  
Zhaokang Cheng
Keyword(s):  
Infarct Size ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Cardiomyocyte Apoptosis ◽  
Neonatal Rat ◽  
Mouse Heart ◽  
Wild Type ◽  
Rat Cardiomyocytes

Background: Reperfusion therapy, an effective treatment for myocardial infarction, triggers ischemia-reperfusion (I/R) injury and eventually may result in heart failure. Retinoblastoma-like 2 (Rbl2), a major retinoblastoma family member expressed in the heart, maintains the postmitotic state of adult cardiac myocytes. However, the role of Rbl2 in myocardial I/R injury remains unclear. We hypothesize that Rbl2 deficiency exacerbates myocardial injury following I/R. Methods and results: Wild type C57BL/6 (8–10-week, male) mice were subjected to 30 min of ischemia followed reperfusion. I/R induced phosphorylation of Rbl2 at Ser952, which has been associated with Rbl2 protein inactivation. To determine the role of Rbl2 in vivo, Rbl2-deficient mice and wild-type littermates were subjected to I/R and infarct size was evaluated by Evans blue/TTC staining. Rbl2 deficiency significantly increased infarct size at 24 h post I/R when compared with wild-type littermate controls. Echocardiography and Masson’s trichrome staining revealed that Rbl2 deficiency exacerbated I/R-induced cardiac dysfunction and fibrosis. Moreover, ablation of Rbl2 exacerbated I/R-induced cardiomyocyte apoptosis, as evidenced by the increased TUNEL positive signal. Consistently, knockdown of Rbl2 augmented H 2 O 2 -induced cleavage of PARP and caspase 3 in neonatal rat cardiomyocytes , suggesting that depletion of Rbl2 exacerbated oxidative stress-induced cardiomyocyte apoptosis. Mechanistically, both I/R and H 2 O 2 induced expression of the pro-apoptotic protein BNIP3, which was augmented by depletion of Rbl2. Since the BNIP3 promoter contains an E2F-binding site, we further examined the levels of the transcriptional activator E2F1 and the transcriptional repressor E2F4. Western blotting revealed that disruption of Rbl2 reduced E2F4 but increased E2F1 levels in mouse heart both at baseline and following I/R. Conclusion: Our findings suggest that Rbl2 deficiency exacerbates cardiomyocyte apoptosis and ischemia-reperfusion injury by augmenting E2F1-mediated BNIP3 expression.

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