scholarly journals Glucosamine protects neonatal cardiomyocytes from ischemia-reperfusion injury via increased protein O-GlcNAc and increased mitochondrial Bcl-2

2008 ◽  
Vol 294 (6) ◽  
pp. C1509-C1520 ◽  
Author(s):  
Voraratt Champattanachai ◽  
Richard B. Marchase ◽  
John C. Chatham
Keyword(s):  
Protective Effect ◽  
Ventricular Myocytes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Neonatal Rat ◽  
Cellular Injury ◽  
Protective Effects ◽  
Neonatal Cardiomyocytes ◽  
Glcnac Transferase ◽  
Neonatal Rat Ventricular Myocytes

We have previously reported that glucosamine protected neonatal rat ventricular myocytes against ischemia-reperfusion (I/R) injury, and this was associated with an increase in protein O-linked- N-acetylglucosamine ( O-GlcNAc) levels. However, the protective effect of glucosamine could be mediated via pathways other that O-GlcNAc formation; thus the initial goal of the present study was to determine whether increasing O-GlcNAc transferase (OGT) expression, which catalyzes the formation of O-GlcNAc, had a protective effect similar to that of glucosamine. To better understand the potential mechanism underlying O-GlcNAc-mediated cytoprotection, we examined whether increased O-GlcNAc levels altered the expression and translocation of members of the Bcl-2 protein family. Both glucosamine (5 mM) and OGT overexpression increased basal and I/R-induced O-GlcNAc levels, significantly decreased cellular injury, and attenuated loss of cytochrome c. Both interventions also attenuated the loss of mitochondrial membrane potential induced by H2O2 and were also associated with an increase in mitochondrial Bcl-2 levels but had no effect on Bad or Bax levels. Compared with glucosamine and OGT overexpression, NButGT (100 μM), an inhibitor of O-GlcNAcase, was less protective against I/R and H2O2 and did not affect Bcl-2 expression, despite a 5- to 10-fold greater increase in overall O-GlcNAc levels. Decreased OGT expression resulted in lower basal O-GlcNAc levels, prevented the I/R-induced increase in O-GlcNAc and mitochondrial Bcl-2, and increased cellular injury. These results demonstrate that the protective effects of glucosamine are mediated via increased formation of O-GlcNAc and suggest that this is due, in part, to enhanced mitochondrial Bcl-2 translocation.

Glucosamine protects neonatal cardiomyocytes from ischemia-reperfusion injury via increased protein-associated O-GlcNAc

2007 ◽  
Vol 292 (1) ◽  
pp. C178-C187 ◽  
Author(s):  
Voraratt Champattanachai ◽  
Richard B. Marchase ◽  
John C. Chatham
Keyword(s):  
Cell Viability ◽  
Cell Survival ◽  
Ventricular Myocytes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Neonatal Rat ◽  
Activated T Cells ◽  
Neonatal Cardiomyocytes ◽  
Hexosamine Biosynthesis ◽  
Glcnac Transferase

Increased levels of protein O-linked N-acetylglucosamine ( O-GlcNAc) have been shown to increase cell survival following stress. Therefore, the goal of this study was to determine whether in isolated neonatal rat ventricular myocytes (NRVMs) an increase in protein O-GlcNAcylation resulted in improved survival and viability following ischemia-reperfusion (I/R). NRVMs were exposed to 4 h of ischemia and 16 h of reperfusion, and cell viability, necrosis, apoptosis, and O-GlcNAc levels were assessed. Treatment of cells with glucosamine, hyperglycemia, or O-(2-acetamido-2-deoxy-d-glucopyranosylidene)-amino- N-phenylcarbamate(PUGNAc), an inhibitor of O-GlcNAcase, significantly increased O-GlcNAc levels and improved cell viability, as well as reducing both necrosis and apoptosis compared with untreated cells following I/R. Alloxan, an inhibitor of O-GlcNAc transferase, markedly reduced O-GlcNAc levels and exacerbated I/R injury. The improved survival with hyperglycemia was attenuated by azaserine, which inhibits glucose metabolism via the hexosamine biosynthesis pathway. Reperfusion in the absence of glucose reduced O-GlcNAc levels on reperfusion compared with normal glucose conditions and decreased cell viability. O-GlcNAc levels significantly correlated with cell viability during reperfusion. The effects of glucosamine and PUGNAc on cellular viability were associated with reduced calcineurin activation as measured by translocation of nuclear factor of activated T cells, suggesting that increased O-GlcNAc levels may attenuate I/R induced increase in cytosolic Ca2+. These data support the concept that activation of metabolic pathways leading to an increase in O-GlcNAc levels is an endogenous stress-activated response and that augmentation of this response improves cell survival. Thus strategies designed to activate these pathways may represent novel interventions for inducing cardioprotection.

Abstract 318: Targeting of Tp53inp1 by Mir-221 to Reduce P62-mediated Autophagy is Cardioprotective in Ischemia / Reperfusion Injury

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Peipei Wang ◽  
Qiying Chen ◽  
Arthur M Richards
Keyword(s):  
Protective Effect ◽  
Cell Count ◽  
Cell Injury ◽  
Ventricular Myocytes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Neonatal Rat ◽  
Autophagosome Formation ◽  
Direct Targeting ◽  
Neonatal Rat Ventricular Myocytes

Purpose: Tumor protein 53-induced nuclear protein 1 (Tp53inp1) acts as a tumor suppressor by inducing cell death. Tp53inp1 mRNA is a predicted target of miR-221. Whether targeting Tp53inp1 plays a role in miR-221-mediated cardioprotection has not been investigated. We hypothesized that miRNA-221 directly targets Tp53inp1 to reduce ischemia/reperfusion (I/R)-induced autophagy. Method: Myoblast H9c2 cells underwent 16 hours 0.2% O 2 hypoxia followed by 2 hours re-oxygenation (H-R, simulating I/R). H9c2 were transfected with miRNA-221 mimic (25 nmol) and scrambled mimic control (miR-221 and MC). Cell count/viability, WST assay, cell injury-induced LDH release, and GFP-LC3 labeled autophagosome formation were measured. Cells were collected for RT-qPCR and western blot (WB) analyses. pCMV-Myc-Tp53inp1 and pcDNA3.1-Flag-p62 plasmids were cloned and transfected into H9c2 for recovery and immuno-precipitation (IP) studies. The effects of miRNA-221 inhibitor in H9c2 were also assessed. Results: miR-221 significantly reduced H-R injury as indicated by higher cell count/viability and WST activity, and reduced LDH (miR-221 vs. MC p<0.05). qPCR confirmed that (1) miRNA-221 expression was reduced in H-R; (2) RISC-loaded (IP pull-down Ago-2) miRNA-221 increased by ~80 fold and reduced by 95% following mimic and inhibitor transfection respectively; (3) Increased Tp53inp1 following H-R was reversed by miR-221. miR-221 inhibited H-R induced autophagosome formation (GFP-LC3). WB indicated (1) increase of LC3-I/II ratio and p62, indicators of reduced autophagy, and (2) decrease of Tp53inp1 by miR-221. IP pull-down Myc-Tp53inp1 indicated the formation of p62-Tp53inp1 complex. The protective effect of miR-221 was abolished by Tp53inp1 overexpression (pCMV-Myc-Tp53inp1 and miRNA-221 mimic co-transfection). The protective effect was corroborated in neonatal rat ventricular myocytes (NRVM). MiRNA-221 inhibitor induced reverse effects. Conclusion: The cardioprotection of miR-221 entails direct targeting of Tp53inp1 which reducing p62-Tp53inp1 complex formation and inhibiting H-R-induced autophagy.

Glucosamine inhibits angiotensin II-induced cytoplasmic Ca2+ elevation in neonatal cardiomyocytes via protein-associated O-linked N-acetylglucosamine

2006 ◽  
Vol 290 (1) ◽  
pp. C57-C65 ◽  
Author(s):  
Tamas Nagy ◽  
Voraratt Champattanachai ◽  
Richard B. Marchase ◽  
John C. Chatham
Keyword(s):  
Ventricular Myocytes ◽  
Neonatal Rat ◽  
Ang Ii ◽  
Neonatal Cardiomyocytes ◽  
Hexosamine Biosynthesis ◽  
Intracellular Ca ◽  
Glcnac Transferase ◽  
Neonatal Rat Ventricular Myocytes ◽  
The Relationship ◽  
Hexosamine Biosynthesis Pathway

We previously reported that glucosamine and hyperglycemia attenuate the response of cardiomyocytes to inositol 1,4,5-trisphosphate-generating agonists such as ANG II. This appears to be related to an increase in flux through the hexosamine biosynthesis pathway (HBP) and decreased Ca2+ entry into the cells; however, a direct link between HBP and intracellular Ca2+ homeostasis has not been established. Therefore, using neonatal rat ventricular myocytes, we investigated the relationship between glucosamine treatment; the concentration of UDP- N-acetylglucosamine (UDP-GlcNAc), an end product of the HBP; and the level of protein O-linked N-acetylglucosamine ( O-GlcNAc) on ANG II-mediated changes in intracellular free Ca2+ concentration ([Ca2+]i). We found that glucosamine blocked ANG II-induced [Ca2+]i increase and that this phenomenon was associated with a significant increase in UDP-GlcNAc and O-GlcNAc levels. O-(2-acetamido-2-deoxy-d-glucopyranosylidene)-amino- N-phenylcarbamate, an inhibitor of O-GlcNAcase that increased O-GlcNAc levels without changing UDP-GlcNAc concentrations, mimicked the effect of glucosamine on the ANG II-induced increase in [Ca2+]i. An inhibitor of O-GlcNAc-transferase, alloxan, prevented the glucosamine-induced increase in O-GlcNAc but not the increase in UDP-GlcNAc; however, alloxan abrogated the inhibition of the ANG II-induced increase in [Ca2+]i. These data support the notion that changes in O-GlcNAc levels mediated via increased HBP flux may be involved in the regulation of [Ca2+]i homeostasis in the heart.

scholarly journals The Protective Effect of Total Flavones from Rhododendron simsii Planch. on Myocardial Ischemia/Reperfusion Injury and Its Underlying Mechanism

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Sheng-Yong Luo ◽  
Qing-Hua Xu ◽  
Gong Peng ◽  
Zhi-Wu Chen
Keyword(s):  
Myocardial Infarction ◽  
Protective Effect ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Assay Method ◽  
Protective Effects ◽  
Rhododendron Simsii ◽  
Rhoa Activity ◽  
Protein Expressions

Objectives. Total flavones from Rhododendron simsii Planch. (TFR) are the effective part extracted from the flowers of Rhododendron simsii Planch. and have obvious protective effects against cerebral ischemic or myocardial injuries in rabbits and rats. However, their mechanism of cardioprotection is still unrevealed. Therefore, the present study was designed to investigate the effect of TFR on myocardial I/R injury and the underlying mechanism. Methods. TFR groups were treated by gavage once a day for 3 days at a dose of 20, 40, and 80 mg/kg, respectively, and then the model of myocardial I/R injury was established. Myocardial infarction, ST-segment elevation, and the expression of UTR, ROCK1, ROCK2, and p-MLC protein in rat myocardium were determined at 90 min after reperfusion. UTR siRNA in vivo transfection and competition binding assay method were used to study the relationship between the protective effect of TFR and UTR. Results. The expression of UTR protein markedly decreased in myocardium of UTR siRNA transfection group rats. TFR could significantly reduce the infarct size and inhibit the increase of RhoA activity and ROCK1, ROCK2, and p-MLC protein expressions both in WT and UTR knockdown rats. The reducing rate of TFR in myocardial infarction area, RhoA activity, and ROCK1, ROCK2, and p-MLC protein expressions in UTR knockdown rats decreased markedly compared with that in WT rats. In addition, TFR had no obvious effect on the increase of ΣST in UTR knockdown rats in comparison with that in model group. In particular, TFR could significantly inhibit the combination of [I125]-hu-II and UTR, and IC50 was 0.854 mg/l. Conclusions. The results indicate that the protective effect of TFR on I/R injury may be correlated with its blocking UTR and the subsequent inhibition of RhoA/ROCK signaling pathway.

Protective Effect of Ginsenoside Rb1 Mixing with Several Lung Flush Solutions on Pulmonary Ischemia-Reperfusion Injury

2014 ◽  
Vol 884-885 ◽  
pp. 625-629
Author(s):  
Feng Wu Lin ◽  
Chuan Zhang ◽  
Qiang Zhang ◽  
Kun Peng Cheng ◽  
Nan Gao ◽  
...  
Keyword(s):  
Protective Effect ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Weight Ratio ◽  
Protective Effects ◽  
Ginsenoside Rb1 ◽  
Wet Weight ◽  
Pulmonary Ischemia ◽  
Dextran Solution

Objective: To evaluate the protective effects of ginsenoside Rb1 mixed with LPD compared to mixed with several other lung flush solutions on ischemia-reperfusion injury. Method: Three group of rabbit lungs were perfused with three kinds of mixtures of ginsenoside Rb1 with blood, Euro-Collins solution(EC) or low-potassium-dextran solution(LPD) respectively, then lung dry/wet weight ratio and malondiadehyde(MAD) were examined and histological changes were observed. Result: Lung dry/wet weight ratio of LPD and Rb1 group was higher than that of EC and Rb1 and blood and Rb1 groups, whereas MAD of LPD and Rb1 group was significantly less than that of EC and Rb1 and blood and Rb1 groups（P<0.05）. Histological findings showed less damage in LPD and Rb1 group. Conclusion: Ginsenoside Rb1 mixed with LPD shows a better protective effect on pulmonary ischemia-reperfusion injury compared with other mixtures.

scholarly journals Therapeutic Cell Protective Role of Histochrome under Oxidative Stress in Human Cardiac Progenitor Cells

Marine Drugs ◽  
2019 ◽  
Vol 17 (6) ◽  
pp. 368 ◽  
Author(s):  
Ji Hye Park ◽  
Na-Kyung Lee ◽  
Hye Ji Lim ◽  
Sinthia Mazumder ◽  
Vinoth Kumar Rethineswaran ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Protective Effect ◽  
Progenitor Cells ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
B Cell Lymphoma ◽  
Cardiac Progenitor Cells ◽  
Protective Effects ◽  
Prolonged Incubation ◽  
Apoptotic Proteins

Cardiac progenitor cells (CPCs) are resident stem cells present in a small portion of ischemic hearts and function in repairing the damaged heart tissue. Intense oxidative stress impairs cell metabolism thereby decreasing cell viability. Protecting CPCs from undergoing cellular apoptosis during oxidative stress is crucial in optimizing CPC-based therapy. Histochrome (sodium salt of echinochrome A—a common sea urchin pigment) is an antioxidant drug that has been clinically used as a pharmacologic agent for ischemia/reperfusion injury in Russia. However, the mechanistic effect of histochrome on CPCs has never been reported. We investigated the protective effect of histochrome pretreatment on human CPCs (hCPCs) against hydrogen peroxide (H2O2)-induced oxidative stress. Annexin V/7-aminoactinomycin D (7-AAD) assay revealed that histochrome-treated CPCs showed significant protective effects against H2O2-induced cell death. The anti-apoptotic proteins B-cell lymphoma 2 (Bcl-2) and Bcl-xL were significantly upregulated, whereas the pro-apoptotic proteins BCL2-associated X (Bax), H2O2-induced cleaved caspase-3, and the DNA damage marker, phosphorylated histone (γH2A.X) foci, were significantly downregulated upon histochrome treatment of hCPCs in vitro. Further, prolonged incubation with histochrome alleviated the replicative cellular senescence of hCPCs. In conclusion, we report the protective effect of histochrome against oxidative stress and present the use of a potent and bio-safe cell priming agent as a potential therapeutic strategy in patient-derived hCPCs to treat heart disease.

scholarly journals Involvement of GPR30 in protection effect of Dexmedetomidine against myocardial ischemia/reperfusion injury in rat via AKT pathway

2021 ◽  
Author(s):  
Zheming Shao ◽  
Qihong Shen ◽  
Min Kong ◽  
Huadong Ni ◽  
Xiaomin Hou
Keyword(s):  
Protective Effect ◽  
Molecular Mechanism ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Cardioprotective Effect ◽  
Mechanism Analysis ◽  
Protective Effects ◽  
Akt Inhibitor

Acute myocardial infarction (AMI) is a heart disease that seriously threatens human health. Dexmedetomidine (DEX) has a certain protective effect on cardiac injury. This study investigated the cardioprotective effect of DEX and its potential molecular mechanism in vivo and in vitro. The results showed that DEX could significantly increase the viability of hypoxia/reoxygenation (H/R) treated cardiomyocytes and reduce oxidative damage and apoptosis. Further molecular mechanism analysis showed that the above cardiac protective effects may be related to Akt signaling pathway. In addition, the expression of G-Protein Receptor 30 (GPR30) was promoted after H/R treatment. However, knockdown of GPR30 by shRNA significantly counteracted the cardioprotective effect of DEX. Meanwhile, we constructed a rat model of AMI to investigate the role of GPR30 in vivo. The results showed that DEX significantly reduced the infarct size, and GPR30 agonist G1 enhanced the protective effect of DEX on heart. On the contrary, protein kinase B (AKT) inhibitor LY294002 counteracted the protective effect of DEX on heart, suggesting that GPR30 enhanced the protective effect of DEX on ischemia-reperfusion induced heart injury by regulating AKT related pathways. In conclusion, our study provides a potential target for the clinical treatment of AMI.

Abstract 123: Adenoviral RhoA Regulation of Dynamin-related Protein 1 and Cardiac Mitochondrial Fission

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Cameron S Brand ◽  
Valerie P Tan-Sah ◽  
Joan Heller Brown ◽  
Shigeki Miyamoto
Keyword(s):  
G Protein ◽  
Ventricular Myocytes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Mitochondrial Fission ◽  
G Protein Coupled Receptors ◽  
Neonatal Rat ◽  
Related Protein ◽  
Rhoa Signaling ◽  
G Protein Coupled

G protein coupled receptors can signal downstream through various pathways, including activation of the small G protein RhoA. In cardiomyocytes, RhoA signaling is protective against ischemia/reperfusion injury. We have previously shown that this is mediated through downstream activation of Protein Kinase D (PKD), increased phosphorylation of cofilin, and diminished translocation of pro-apoptotic proteins to the mitochondria (Xiang et al, Sci. Signaling 2013). Mitophagy, a process that removes damaged mitochondria and limits mitochondrial death signaling, has also been suggested to be a cardioprotective response to oxidative stress. A step considered to be preliminary to clearance of damaged mitochondria via mitophagy is mitochondrial fission, and we hypothesized that RhoA signaling increases mitochondrial fission in cardiomyocytes. Constitutively active RhoA expressed in neonatal rat ventricular myocytes (NRVMs) was found to accumulate at the mitochondria. This was associated with an increase in small, fragmented mitochondria as observed by fluorescent confocal microscopy and electron microscopy, indicative of increased mitochondrial fission. The main protein involved in mitochondrial fission, dynamin-related protein 1 (Drp1), translocates from the cytosol to the mitochondria when activated. We used a tagged adenoviral Drp1 construct to determine whether expression of active RhoA changes Drp1 levels at the mitochondria. Mitochondrial Drp1 increased within 12 hours of adenoviral expression of active RhoA. Adenoviral RhoA expression also increased phosphorylation of Drp1 at serine-616 in NRVMs. In summary, we show that in cardiomyocytes, RhoA associates with mitochondria, can increase Drp1 phosphorylation and Drp1 mitochondrial localization, and can induce mitochondrial fission. The relationship between these mitochondrial signaling events and the protein kinases that are involved are currently under investigation. We suggest that G protein coupled receptors that stimulate RhoA can induce Drp1 accumulation and mitochondrial fission, which contributes to their cardioprotective effect.

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