Evidence that intracellular cyclophilin A and cyclophilin A/CD147 receptor-mediated ERK1/2 signalling can protect neurons against in vitro oxidative and ischemic injury

2007 ◽  
Vol 25 (1) ◽  
pp. 54-64 ◽  
Author(s):  
Sherif Boulos ◽  
Bruno P. Meloni ◽  
Peter G. Arthur ◽  
Bernadette Majda ◽  
Christina Bojarski ◽  
...  
Keyword(s):  
Ischemic Injury ◽  
Cyclophilin A

Abstract 3653: Akt3 Offers Stronger Protection than Akt1 Against Brain Injury by Differentially Promoting Mtor Protein Levels In Both In Vitro and In Vivo Stroke Models

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Rong Xie ◽  
Michelle Cheng ◽  
Mei Li ◽  
Robert Sapolsky ◽  
Heng Zhao
Keyword(s):  
Gene Transfer ◽  
Western Blotting ◽  
Ischemic Injury ◽  
Akt Pathway ◽  
Over Expression ◽  
Protein Levels ◽  
Akt Isoforms ◽  
The Brain

Background and Objective: Akt is a serine-threonine kinase that plays critical role in promoting cell survival. Akt consists of three isoforms (Akt1, 2, 3), with Akt3 predominantly expressed in the brain. Although Akt pathway has been shown to mediate neuronal survival in cerebral ischemic injury, it is unclear how these Akt isoforms contribute to neuronal protection, and whether exogenous Akt can protect the brain against ischemic injury or not. In this study, we over-expressed Akt isoforms and its downstream signaling proteins such as FKHR and PRAS40 to investigate the role of the Akt pathway along with its potential relationship with the mTOR pathway in stroke. Methods: Sprauge Dawley rats (250∼280g) were used for all studies. A lentiviral vector consists of a CMV promoter driving IRES-eGFP was used to clone an active Akt 1 and 3 (cAKt 1 and 3), dominant-negative Akt (AktDN), active FKHR (AAA FKHR), and PRAS40. Lentivirus expressing these genes were added to primary mixed cortical cultures for two days prior to oxygen glucose deprivation (OGD) (MOI=1:5). Neuronal survival was measured by LDH release. Lentivirus were stereotaxically injected into the cortex, and rats were subjected to focal ischemia induced by distal MCA occlusion combined with bilateral CCA occlusion. Western blotting and immunofluorescent confocal microscopy were used to detect the expression of Akt isoforms and other proteins in both the Akt and mTOR pathways. Results: Western blotting analysis showed that both endogenous Akt1 and 3 proteins degraded as early as 1 h after stroke, while Akt2 protein remained unchanged until 24 h after stroke. In vitro studies showed that over-expression of both constitutively active cAkt1 and cAkt3 decreased LDH release after OGD, while AktDN worsened neuronal death ( P <0.05). In vivo over-expression of cAkt1, cAkt3 and PRAS40 reduced infarct size after stroke ( P <0.01). Gene transfer of cAkt1 and 3 also promoted protein levels of pAkt (phosphorylated Akt), pPRAS40, pFKHR, pPTEN, pmTOR, but not pGSK3β. Both in vitro and in vivo studies showed that over-expression of cAkt3 resulted in a stronger protection than cAkt1 ( P <0.05). Interestingly, cAkt3 gene transfer preserved both endogenous protein levels of Akt1 and 3, whereas cAkt1 gene transfer only preserved endogenous Akt1. Furthermore, cAkt3 promoted higher pmTOR levels than cAkt1. Treatment of rapamycin, an mTOR inhibitor, blocked the protective effects of both cAkt1 and cAkt3 both in vitro and in vivo. Conclusion: Lentiviral-mediated overexpression of cAkt3 confers stronger protection than that of cAkt1, by maintaining both endogenous Akt1 and Akt3, as well as promoting higher mTOR activities after stroke.

scholarly journals Overexpression of SERCA2a Alleviates Cardiac Microvascular Ischemic Injury by Suppressing Mfn2-Mediated ER/Mitochondrial Calcium Tethering

2021 ◽  
Vol 9 ◽  
Author(s):  
Feng Tian ◽  
Ying Zhang
Keyword(s):  
Endoplasmic Reticulum ◽  
Infarct Size ◽  
Myocardial Infarct ◽  
Ischemic Injury ◽  
Calcium Overload ◽  
Mitochondrial Calcium ◽  
Myocardial Infarct Size ◽  
Hypoxic Injury

Our previous research has shown that type-2a Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA2a) undergoes posttranscriptional oxidative modifications in cardiac microvascular endothelial cells (CMECs) in the context of excessive cardiac oxidative injury. However, whether SERCA2a inactivity induces cytosolic Ca2+ imbalance in mitochondrial homeostasis is far from clear. Mitofusin2 (Mfn2) is well known as an important protein involved in endoplasmic reticulum (ER)/mitochondrial Ca2+ tethering and the regulation of mitochondrial quality. Therefore, the aim of our study was to elucidate the specific mechanism of SERCA2a-mediated Ca2+ overload in the mitochondria via Mfn2 tethering and the survival rate of the heart under conditions of cardiac microvascular ischemic injury. In vitro, CMECs extracted from mice were subjected to 6 h of hypoxic injury to mimic ischemic heart injury. C57-WT and Mfn2KO mice were subjected to a 1 h ischemia procedure via ligation of the left anterior descending branch to establish an in vivo cardiac ischemic injury model. TTC staining, immunohistochemistry and echocardiography were used to assess the myocardial infarct size, microvascular damage, and heart function. In vitro, ischemic injury induced irreversible oxidative modification of SERCA2a, including sulfonylation at cysteine 674 and nitration at tyrosine 294/295, and inactivation of SERCA2a, which initiated calcium overload. In addition, ischemic injury-triggered [Ca2+]c overload and subsequent [Ca2+]m overload led to mPTP opening and ΔΨm dissipation compared with the control. Furthermore, ablation of Mfn2 alleviated SERCA2a-induced mitochondrial calcium overload and subsequent mito-apoptosis in the context of CMEC hypoxic injury. In vivo, compared with that in wild-type mice, the myocardial infarct size in Mfn2KO mice was significantly decreased. In addition, the findings revealed that Mfn2KO mice had better heart contractile function, decreased myocardial infarction indicators, and improved mitochondrial morphology. Taken together, the results of our study suggested that SERCA2a-dependent [Ca2+]c overload led to mitochondrial dysfunction and activation of Mfn2-mediated [Ca2+]m overload. Overexpression of SERCA2a or ablation of Mfn2 expression mitigated mitochondrial morphological and functional damage by modifying the SERCA2a/Ca2+-Mfn2 pathway. Overall, these pathways are promising therapeutic targets for acute cardiac microvascular ischemic injury.

scholarly journals Intravenous injection of cyclophilin A realizes the transient and reversible opening of barrier of neural vasculature through basigin in endothelial cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Narumi Nakada-Honda ◽  
Dan Cui ◽  
Satoshi Matsuda ◽  
Eiji Ikeda
Keyword(s):  
Endothelial Cells ◽  
Single Dose ◽  
Blood Brain Barrier ◽  
Intravenous Injection ◽  
Cyclophilin A ◽  
Brain Barrier ◽  
Blood Brain ◽  
Neural Tissues ◽  
Neural Diseases

AbstractNeural vasculature forms the blood–brain barrier against the delivery of systemically administered therapeutic drugs into parenchyma of neural tissues. Therefore, procedures to open the blood–brain barrier with minimal damage to tissues would lead to the great progress in therapeutic strategy for intractable neural diseases. In this study, through analyses with mouse in vitro brain microvascular endothelial cells and in vivo neural vasculature, we demonstrate that the administration of cyclophilin A (CypA), a ligand of basigin which is expressed in barrier-forming endothelial cells, realizes the artificial opening of blood–brain barrier. Monolayers of endothelial cells lost their barrier properties through the disappearance of claudin-5, an integral tight junction molecule, from cell membranes in a transient and reversible manner. Furthermore, the intravenous injection of a single dose of CypA into mice resulted in the opening of blood–brain barrier for a certain period which enabled the enhanced delivery of systemically administered doxorubicin into the parenchyma of neural tissues. These findings that the pre-injection of a single dose of CypA realizes an artificial, transient as well as reversible opening of blood–brain barrier are considered to be a great step toward the establishment of therapeutic protocols to overcome the intractability of neural diseases.

scholarly journals Expression and Role of Parathyroid Hormone-Related Protein in Human Renal Proximal Tubule Cells during Recovery from ATP Depletion

1999 ◽  
Vol 10 (2) ◽  
pp. 238-244
Author(s):  
ADOLFO GARCÍA-OCAÑA ◽  
SUSAN C. GALBRAITH ◽  
SCOTT K. VAN WHY ◽  
KAI YANG ◽  
LINA GOLOVYAN ◽  
...  
Keyword(s):  
Proximal Tubule ◽  
Recovery Period ◽  
Ischemic Injury ◽  
Atp Depletion ◽  
Proximal Tubule Cell ◽  
Pthrp Expression ◽  
Human Proximal Tubule Cell

Abstract. Parathyroid hormone (PTH)-related protein (PTHrP) is widely expressed in normal fetal and adult tissues and regulates growth and differentiation in a number of organ systems. Although various renal cell types produce PTHrP, and PTHrP expression in rat proximal renal tubules is upregulated in response to ischemic injury in vivo, the role of PTHrP in the kidney is unknown. To study the effects of injury on PTHrP expression and its consequences in more detail, the immortalized human proximal tubule cell line HK-2 was used in an in vitro model of ATP depletion to mimic in vivo renal ischemic injury. These cells secrete PTHrP into conditioned medium and express the type I PTH/PTHrP receptor. Treatment of confluent HK-2 cells for 2 h with substrate-free, glucose-free medium containing the mitochondrial inhibitor antimycin A (1 μM) resulted in 75% depletion of cellular ATP. After an additional 2 h in glucose-containing medium, cellular ATP levels recovered to approximately 75% of baseline levels. PTHrP mRNA levels, as measured in RNase protection assays, peaked at 2 h into the recovery period (at four times baseline expression). The increase in PTHrP mRNA expression was correlated with an increase in PTHrP protein content in HK-2 cells at 2 to 6 h into the recovery period. Heat shock protein-70 mRNA expression was not detectable under baseline conditions but likewise peaked at 2 h into the recovery period. Treatment of HK-2 cells during the recovery period after injury with an anti-PTHrP(1-36) antibody (at a dilution of 1:250) resulted in significant reductions in cell number and uptake of [3H]thymidine, compared with nonimmune serum at the same titer. Similar results were observed in uninjured HK-2 cells. It is concluded that this in vitro model of ATP depletion in a human proximal tubule cell line reproduces the pattern of gene expression previously observed in vivo in rat kidney after ischemic injury and that PTHrP plays a mitogenic role in the proliferative response after energy depletion.

scholarly journals Limiting Ischemic Injury by Inhibition of Excitatory Amino Acid Release

1993 ◽  
Vol 13 (1) ◽  
pp. 88-97 ◽  
Author(s):  
Steven H. Graham ◽  
Jun Chen ◽  
Frank R. Sharp ◽  
Roger P. Simon
Keyword(s):  
Excitatory Amino Acid ◽  
Glutamate Release ◽  
Ischemic Injury ◽  
Retrosplenial Cortex ◽  
Mca Occlusion ◽  
Alternative Approach ◽  
Proximal Middle Cerebral Artery ◽  
Human Use ◽  
Unacceptable Toxicity

Excitatory amino acids (EAAs) are important mediators of ischemic injury in stroke. N-Methyl-d-aspartate (NMDA) receptor antagonists have been shown to be very effective neuroprotective agents in animal models of stroke, but may have unacceptable toxicity for human use. An alternative approach is to inhibit the release of EAAs during stroke. BW1003C87 [5-(2,3,5-trichlorophenyl)-2,4-diaminopyrimidine], a drug that inhibits veratrine-induced release of the EAA glutamate in vitro, was tested in a rat model of proximal middle cerebral artery (MCA) occlusion. BW1003C87 significantly decreased ischemia-induced glutamate release in brain when given either 5 min before or 15 min following permanent MCA occlusion. Pretreated and posttreated rats had smaller infarct volumes and preserved glucose metabolism in the ischemic cortex at 24 h after MCA occlusion. BW1003C87 did not induce heat shock protein in the cingulate or retrosplenial cortex, suggesting that it does not injure neurons in these regions as do NMDA antagonists. These results demonstrate that drugs that inhibit glutamate release in ischemia may be nontoxic and show promise for the treatment of stroke.

scholarly journals Modulator of apoptosis-1 is a potential therapeutic target in acute ischemic injury

2018 ◽  
Vol 39 (12) ◽  
pp. 2406-2418 ◽  
Author(s):  
Su Jing Chan ◽  
Hui Zhao ◽  
Kazuhide Hayakawa ◽  
Chou Chai ◽  
Chong Teik Tan ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Infarct Volume ◽  
Neuronal Loss ◽  
Ischemic Injury ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
In Vivo Models ◽  
The Brain

Modulator of apoptosis 1 (MOAP-1) is a Bax-associating protein highly enriched in the brain. In this study, we examined the role of MOAP-1 in promoting ischemic injuries following a stroke by investigating the consequences of MOAP-1 overexpression or deficiency in in vitro and in vivo models of ischemic stroke. MOAP-1 overexpressing SH-SY5Y cells showed significantly lower cell viability following oxygen and glucose deprivation (OGD) treatment when compared to control cells. Consistently, MOAP-1−/− primary cortical neurons were observed to be more resistant against OGD treatment than the MOAP-1+/+ primary neurons. In the mouse transient middle cerebral artery occlusion (tMCAO) model, ischemia triggered MOAP-1/Bax association, suggested activation of the MOAP-1-dependent apoptotic cascade. MOAP-1−/− mice were found to exhibit reduced neuronal loss and smaller infarct volume 24 h after tMCAO when compared to MOAP-1+/+ mice. Correspondingly, MOAP-1−/− mice also showed better integrity of neurological functions as demonstrated by their performance in the rotarod test. Therefore, both in vitro and in vivo data presented strongly support the conclusion that MOAP-1 is an important apoptotic modulator in ischemic injury. These results may suggest that a reduction of MOAP-1 function in the brain could be a potential therapeutic approach in the treatment of acute stroke.

Abstract 013: Role for β-Arrestins in Stem/Precursor Cell Function and Cardiac Regeneration

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Anna M Gumpert ◽  
Mai Chen ◽  
Henriette Brinks ◽  
Jang-Whan Bae ◽  
Karsten Peppel ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Cell Death ◽  
Cell Function ◽  
Ischemic Injury ◽  
Precursor Cells ◽  
Cardiac Repair ◽  
Precursor Cell ◽  
Gpcr Desensitization

Chronic heart failure after myocardial injury (MI) is characterized by an extensive loss of myocytes due to considerable cell death. Bone marrow derived stem cells (BMSCs) can transdifferentiate and show potential for regenerating the myocardium after MI. Stem cell mobilization, egress from the bone marrow and recruitment to the site of injury can be regulated by signals through G protein coupled receptors (GPCRs). βArrestins have signalling and scaffolding functions and act as downstream regulators of GPCR desensitization and endocytosis. We explored the potential role for βArrestins in cardiac precursor cell function, concentrating on BMSCs. Using knockout (KO) mice, we investigated the role βArrestin1 (βArr1) and βArrestin2 (βArr2), their modulation of regenerative competence of BMSCs and their contribution to cardiac repair after ischemic injury. in vitro, we observed that BM derived cells devoid of either βArr1 or βArr2 are slower to proliferate, colonize and migrate, compared to wild type (WT) BM cells. We also observed elevated cell death in βArr2 deficient cells following oxidative stress. Additionally, the number of cKit+ stem cells, thought to be potential cardiac precursor cells, was significantly lower in the BM and blood of βArr KO vs WT. Similarly, BM and blood of the chimeras contained fewer and less viable cardiac stem/precursor cells pre and post MI, compared to WT transplanted controls. In our in vivo study, we carried out BM transplants to determine whether the βArrs may be involved in cardiac repair. WT mice were irradiated and received BM transplants from WT, βArr1 KO or βArr2 KO mice. Following BM reconstitution, mice underwent MI and their recovery was monitored. Interestingly, chimeric mice with βArr1 and βArr2 KO BM had significantly inferior outcomes, including significantly decreased post MI survival with βArr2 KO BM and both βArr chimeras had significantly lower cardiac function post MI than mice receiving WT BM. Histology revealed that both chimeras developed larger infarcts and hypertrophy at an faster rate. We conclude that βArrs play a novel role downstream of GPCR desensitization in cardiac progenitor cells in BM and appear to be critically involved in the heart’s response to ischemic injury via cardiac repair and regeneration.

scholarly journals Cyclophilin a as a Mediator of Tissue Injure and Nephrotoxicity

2012 ◽  
Vol 4 (2) ◽  
pp. 42-44
Author(s):  
Grace Moscoso-Solorzano ◽  
Gianna Mastroianni-Kirsztajn
Keyword(s):  
Molecular Mechanisms ◽  
Tissue Injury ◽  
Cyclophilin A ◽  
Common Mechanism ◽  
Ppiase Activity ◽  
Expression Of Genes ◽  
Inflammatory Stimuli ◽  
Genes Encoding ◽  
Inflammatory Processes

Cyclophilin A (CypA) belongs to the peptidyl-prolil isomerase (PPlase) family of proteins and it is also known as the cellular receptor for cyclosporine A (CsA). CsA binds to CypA and inhibits the PPIase activity, but the CypA-CsA complex also binds to calcineurin that promotes the expression of genes encoding cytokines and other proteins required for immune response. In addition, the polymorphism variation of CypA promoter seems to have an influence on the expression of CypA in in vitro studies. CypA was also implicated in inflammatory processes (such as, among others, those observed in rheumatoid arthritis, atherosclerotic disease, nephrotoxicity) and it can be secreted by cells in response to inflammatory stimuli. CypA can also have a role in the molecular mechanisms by which CsA induces nephroxicity but these remain poorly understood. Recent studies suggest that CsA inhibition of CypA PPlase activity is a possible mechanism of this drug toxicity. In addition, CypA overexpression could be protective against CsA nephrotoxicity. Finally, the putative common mechanism by which CypA could be involved in CsA nephrotoxicity and tissue injury is related to its proinflammatory effects in cells.

scholarly journals Sal B Alleviates Myocardial Ischemic Injury by Inhibiting TLR4 and the Priming Phase of NLRP3 Inflammasome

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4416 ◽  
Author(s):  
Yang Hu ◽  
Qingju Li ◽  
Yunzheng Pan ◽  
Li Xu
Keyword(s):  
Nlrp3 Inflammasome ◽  
Troponin I ◽  
Salvia Miltiorrhiza ◽  
Ischemic Injury ◽  
Water Soluble ◽  
Dependent Manner ◽  
Priming Phase ◽  
Myocardial Ischemic Injury

Salvianolic acid B is one of the main water-soluble components of Salvia miltiorrhiza Bge. Many reports have shown that it has significant anti-myocardial ischemia effect. However, the underlying mechanism remains unclear. Our present study demonstrated that Sal B could alleviate myocardial ischemic injury by inhibiting the priming phase of NLRP3 inflammasome. In vivo, serum c-troponin I (cTn), lactate dehydrogenase (LDH) levels, the cardiac function and infract size were examined. We found that Sal B could notably reduce the myocardial ischemic injury caused by ligation of the left anterior descending coronary artery. In vitro, Sal B down-regulated the TLR4/NF-κB signaling cascades in lipopolysaccharide (LPS)-stimulated H9C2 cells. Furthermore, Sal B reduced the expression levels of IL-1β and NLRP3 inflammasome in a dose-dependent manner. In short, our study provided evidence that Sal B could attenuate myocardial ischemic injury via inhibition of TLR4/NF-κB/NLRP3 signaling pathway. And in an upstream level, MD-2 may be the potential target.

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