scholarly journals Role of sulfiredoxin as a peroxiredoxin-2 denitrosylase in human iPSC-derived dopaminergic neurons

2016 ◽  
Vol 113 (47) ◽  
pp. E7564-E7571 ◽  
Author(s):  
Carmen R. Sunico ◽  
Abdullah Sultan ◽  
Tomohiro Nakamura ◽  
Nima Dolatabadi ◽  
James Parker ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Redox Homeostasis ◽  
Induced Pluripotent Stem Cell ◽  
Neural Cells ◽  
Dependent Manner ◽  
Protective Function ◽  
Peroxiredoxin 2 ◽  
Induced Pluripotent

Recent studies have pointed to protein S-nitrosylation as a critical regulator of cellular redox homeostasis. For example, S-nitrosylation of peroxiredoxin-2 (Prx2), a peroxidase widely expressed in mammalian neurons, inhibits both enzymatic activity and protective function against oxidative stress. Here, using in vitro and in vivo approaches, we identify a role and reaction mechanism of the reductase sulfiredoxin (Srxn1) as an enzyme that denitrosylates (thus removing -SNO) from Prx2 in an ATP-dependent manner. Accordingly, by decreasing S-nitrosylated Prx2 (SNO-Prx2), overexpression of Srxn1 protects dopaminergic neural cells and human-induced pluripotent stem cell (hiPSC)-derived neurons from NO-induced hypersensitivity to oxidative stress. The pathophysiological relevance of this observation is suggested by our finding that SNO-Prx2 is dramatically increased in murine and human Parkinson’s disease (PD) brains. Our findings therefore suggest that Srxn1 may represent a therapeutic target for neurodegenerative disorders such as PD that involve nitrosative/oxidative stress.

Targeting PPARalpha in Alzheimer's Disease

2018 ◽  
Vol 15 (4) ◽  
pp. 345-354 ◽  
Author(s):  
Barbara D'Orio ◽  
Anna Fracassi ◽  
Maria Paola Cerù ◽  
Sandra Moreno
Keyword(s):  
Oxidative Stress ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Molecular Mechanisms ◽  
Redox Homeostasis ◽  
Antioxidant Response ◽  
Peroxisome Proliferator ◽  
Prevailing Paradigm

Background: The molecular mechanisms underlying Alzheimer's disease (AD) are yet to be fully elucidated. The so-called “amyloid cascade hypothesis” has long been the prevailing paradigm for causation of disease, and is today being revisited in relation to other pathogenic pathways, such as oxidative stress, neuroinflammation and energy dysmetabolism. The peroxisome proliferator-activated receptors (PPARs) are expressed in the central nervous system (CNS) and regulate many physiological processes, such as energy metabolism, neurotransmission, redox homeostasis, autophagy and cell cycle. Among the three isotypes (α, β/δ, γ), PPARγ role is the most extensively studied, while information on α and β/δ are still scanty. However, recent in vitro and in vivo evidence point to PPARα as a promising therapeutic target in AD. Conclusion: This review provides an update on this topic, focussing on the effects of natural or synthetic agonists in modulating pathogenetic mechanisms at AD onset and during its progression. Ligandactivated PPARα inihibits amyloidogenic pathway, Tau hyperphosphorylation and neuroinflammation. Concomitantly, the receptor elicits an enzymatic antioxidant response to oxidative stress, ameliorates glucose and lipid dysmetabolism, and stimulates autophagy.

scholarly journals Persistence of intramyocardially transplanted murine induced pluripotent stem cell-derived cardiomyocytes from different developmental stages

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gabriel Peinkofer ◽  
Martina Maass ◽  
Kurt Pfannkuche ◽  
Agapios Sachinidis ◽  
Stephan Baldus ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Stem Cell ◽  
Cell Adhesion ◽  
Developmental Stage ◽  
Pluripotent Stem Cell ◽  
Induced Pluripotent Stem Cell ◽  
Induced Pluripotent

Abstract Background Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) are regarded as promising cell type for cardiac cell replacement therapy, but it is not known whether the developmental stage influences their persistence and functional integration in the host tissue, which are crucial for a long-term therapeutic benefit. To investigate this, we first tested the cell adhesion capability of murine iPSC-CM in vitro at three different time points during the differentiation process and then examined cell persistence and quality of electrical integration in the infarcted myocardium in vivo. Methods To test cell adhesion capabilities in vitro, iPSC-CM were seeded on fibronectin-coated cell culture dishes and decellularized ventricular extracellular matrix (ECM) scaffolds. After fixed periods of time, stably attached cells were quantified. For in vivo experiments, murine iPSC-CM expressing enhanced green fluorescent protein was injected into infarcted hearts of adult mice. After 6–7 days, viable ventricular tissue slices were prepared to enable action potential (AP) recordings in transplanted iPSC-CM and surrounding host cardiomyocytes. Afterwards, slices were lysed, and genomic DNA was prepared, which was then used for quantitative real-time PCR to evaluate grafted iPSC-CM count. Results The in vitro results indicated differences in cell adhesion capabilities between day 14, day 16, and day 18 iPSC-CM with day 14 iPSC-CM showing the largest number of attached cells on ECM scaffolds. After intramyocardial injection, day 14 iPSC-CM showed a significant higher cell count compared to day 16 iPSC-CM. AP measurements revealed no significant difference in the quality of electrical integration and only minor differences in AP properties between d14 and d16 iPSC-CM. Conclusion The results of the present study demonstrate that the developmental stage at the time of transplantation is crucial for the persistence of transplanted iPSC-CM. iPSC-CM at day 14 of differentiation showed the highest persistence after transplantation in vivo, which may be explained by a higher capability to adhere to the extracellular matrix.

scholarly journals Mn Inhibits GSH Synthesis via Downregulation of Neuronal EAAC1 and Astrocytic xCT to Cause Oxidative Damage in the Striatum of Mice

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xinxin Yang ◽  
Haibo Yang ◽  
Fengdi Wu ◽  
Zhipeng Qi ◽  
Jiashuo Li ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Oxidative Damage ◽  
Dependent Manner ◽  
Protein Levels ◽  
Key Factor ◽  
Protein Sulfhydryl ◽  
Mrna And Protein Expression ◽  
The Brain

Excessive manganese (Mn) can accumulate in the striatum of the brain following overexposure. Oxidative stress is a well-recognized mechanism in Mn-induced neurotoxicity. It has been proven that glutathione (GSH) depletion is a key factor in oxidative damage during Mn exposure. However, no study has focused on the dysfunction of GSH synthesis-induced oxidative stress in the brain during Mn exposure. The objective of the present study was to explore the mechanism of Mn disruption of GSH synthesis via EAAC1 and xCT in vitro and in vivo. Primary neurons and astrocytes were cultured and treated with different doses of Mn to observe the state of cells and levels of GSH and reactive oxygen species (ROS) and measure mRNA and protein expression of EAAC1 and xCT. Mice were randomly divided into seven groups, which received saline, 12.5, 25, and 50 mg/kg MnCl2, 500 mg/kg AAH (EAAC1 inhibitor) + 50 mg/kg MnCl2, 75 mg/kg SSZ (xCT inhibitor) + 50 mg/kg MnCl2, and 100 mg/kg NAC (GSH rescuer) + 50 mg/kg MnCl2 once daily for two weeks. Then, levels of EAAC1, xCT, ROS, GSH, malondialdehyde (MDA), protein sulfhydryl, carbonyl, 8-hydroxy-2-deoxyguanosine (8-OHdG), and morphological and ultrastructural features in the striatum of mice were measured. Mn reduced protein levels, mRNA expression, and immunofluorescence intensity of EAAC1 and xCT. Mn also decreased the level of GSH, sulfhydryl, and increased ROS, MDA, 8-OHdG, and carbonyl in a dose-dependent manner. Injury-related pathological and ultrastructure changes in the striatum of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GSH synthesis through inhibition of EAAC1 and xCT to trigger oxidative damage in the striatum.

scholarly journals A novel mitochondrial enriched antioxidant protects neurons against acute oxidative stress

2017 ◽  
Author(s):  
Nicola J. Drummond ◽  
Nick O. Davies ◽  
Janet E. Lovett ◽  
Mark R. Miller ◽  
Graeme Cook ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Damage ◽  
Radical Scavenging ◽  
Head Group ◽  
Neural Cells ◽  
Zebrafish Model ◽  
Free System ◽  
Age Related

AbstractExcessive reactive oxygen species (ROS) can damage proteins, lipids, and DNA, which result in cell damage and death. The outcomes can be acute, as seen in stroke, or more chronic as observed in age-related diseases such as Parkinson’s disease. Here we investigate the antioxidant ability of a novel synthetic flavonoid, Proxison (7-decyl-3-hydroxy-2-(3,4,5-trihydroxyphenyl)-4-chromenone), using a range of in vitro and in vivo approaches. We show that, while it has radical scavenging ability on par with other flavonoids in a cell-free system, Proxison is orders of magnitude more potent than natural flavonoids at protecting neural cells against oxidative stress and is capable of rescuing damaged cells. The unique combination of a lipophilic hydrocarbon tail with a modified polyphenolic head group promotes efficient cellular uptake and mitochondrial localisation of Proxison. Importantly, in vivo administration of Proxison demonstrated effective and well tolerated neuroprotection against oxidative stress in a zebrafish model of dopaminergic neuronal loss.

Abstract 246: Human Induced Pluripotent Stem Cells Reveal Mitophagy as an Essential Process Against Diabetic Cardiomyopathy

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Sang-Ging Ong ◽  
Won Hee Lee ◽  
Kazuki Kodo ◽  
Haodi Wu ◽  
Joseph C Wu
Keyword(s):  
Oxidative Stress ◽  
Diabetic Cardiomyopathy ◽  
Mitochondrial Fission ◽  
Induced Pluripotent Stem Cell ◽  
Mitochondrial Fragmentation ◽  
Normal Cells ◽  
Mitochondrial Pathology ◽  
Vitro Model ◽  
Induced Pluripotent

Diabetic cardiomyopathy is a common consequence of diabetes and associated with mitochondrial pathology. Using human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) as an in vitro model of diabetes, we sought to understand the role of mitophagy, a process that selectively degrades mitochondria through the autophagy-lysosome pathway as a crucial quality control pathway against diabetic cardiomyopathy. We first showed that iPSC-CMs exposed to a diabetic milieu demonstrated increased hypertrophy, impaired calcium signaling, and higher oxidative stress. Flow cytometry analysis of iPSC-CMs subjected to diabetic conditions revealed two distinct population of cells (normal and hypertrophied), suggesting a heterogeneous response to hyperglycemia. In these cells, hypertrophied iPSC-CMs were found to have reduced mitophagy compared to normal cells when exposed to hyperglycemia. In addition, we showed that mitochondrial fragmentation was also decreased in the hypertrophied iPSC-CMs compared to normal cells upon exposure to hyperglycemia, demonstrating a link between mitochondrial fragmentation and mitophagy. Surprisingly, pretreatment of iPSC-CMs with a non-selective antioxidant, N-(2-mercaptopropionyl)-glycine, not only failed to limit the deleterious effects of hyperglycemia, but actually led to increased hypertrophy and cell death. We found that mitophagy was significantly reduced in iPSC-CMs following antioxidant treatment, suggesting the need of mild oxidative stress as a trigger for mitophagy. Future studies are warranted to further investigate the association between oxidative stress, mitochondrial fragmentation, and mitochondrial fission as targets against diabetic cardiomyopathy.

scholarly journals Discovery of a dual inhibitor of NQO1 and GSTP1 for treating glioblastoma

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Kecheng Lei ◽  
Xiaoxia Gu ◽  
Alvaro G. Alvarado ◽  
Yuhong Du ◽  
Shilin Luo ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Crystal Structures ◽  
Active Sites ◽  
Redox Homeostasis ◽  
Growth Factor Receptor ◽  
Quinone Oxidoreductase ◽  
Cancer Proliferation ◽  
Dual Inhibitor

Abstract Background Glioblastoma (GBM) is a universally lethal tumor with frequently overexpressed or mutated epidermal growth factor receptor (EGFR). NADPH quinone oxidoreductase 1 (NQO1) and glutathione-S-transferase Pi 1 (GSTP1) are commonly upregulated in GBM. NQO1 and GSTP1 decrease the formation of reactive oxygen species (ROS), which mediates the oxidative stress and promotes GBM cell proliferation. Methods High-throughput screen was used for agents selectively active against GBM cells with EGFRvIII mutations. Co-crystal structures were revealed molecular details of target recognition. Pharmacological and gene knockdown/overexpression approaches were used to investigate the oxidative stress in vitro and in vivo. Results We identified a small molecular inhibitor, “MNPC,” that binds to both NQO1 and GSTP1 with high affinity and selectivity. MNPC inhibits NQO1 and GSTP1 enzymes and induces apoptosis in GBM, specifically inhibiting the growth of cell lines and primary GBM bearing the EGFRvIII mutation. Co-crystal structures between MNPC and NQO1, and molecular docking of MNPC with GSTP1 reveal that it binds the active sites and acts as a potent dual inhibitor. Inactivation of both NQO1 and GSTP1 with siRNA or MNPC results in imbalanced redox homeostasis, leading to apoptosis and mitigated cancer proliferation in vitro and in vivo. Conclusions Thus, MNPC, a dual inhibitor for both NQO1 and GSTP1, provides a novel lead compound for treating GBM via the exploitation of specific vulnerabilities created by mutant EGFR.

scholarly journals An Antioxidant Phytotherapy to Rescue Neuronal Oxidative Stress

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Zhihong Lin ◽  
Danni Zhu ◽  
Yongqing Yan ◽  
Boyang Yu ◽  
Qiujuan Wang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Aqueous Extract ◽  
Ischemia Reperfusion ◽  
Brain Infarction ◽  
Reaction System ◽  
Artery Occlusion ◽  
Dependent Manner ◽  
Endogenous Antioxidant

Oxidative stress is involved in the pathogenesis of ischemic neuronal injury. A Chinese herbal formula composed ofPoria cocos(Chinese name:Fu Ling),Atractylodes macrocephala(Chinese name:Bai Zhu) andAngelica sinensis(Chinese names:Danggui, Dong quai, Donggui; Korean name:Danggwi) (FBD), has been proved to be beneficial in the treatment of cerebral ischemia/reperfusion (I/R).This study was carried out to evaluate the protective effect of FBD against neuronal oxidative stressin vivoandin vitro. Rat I/R were established by middle cerebral artery occlusion (MCAO) for 1 h, followed by 24 h reperfusion. MCAO led to significant depletion in superoxide dismutase and glutathione and rise in lipid peroxidation (LPO) and nitric oxide in brain. The neurological deficit and brain infarction were also significantly elevated by MCAO as compared with sham-operated group. All the brain oxidative stress and damage were significantly attenuated by 7 days pretreatment with the aqueous extract of FBD (250 mg kg−1, p.o.). Moreover, cerebrospinal fluid sampled from FBD-pretreated rats protected PC12 cells against oxidative insult induced by 0.2 mM hydrogen peroxide, in a concentration and time-dependent manner (IC5010.6%, ET501.2 h). However, aqueous extract of FBD just slightly scavenged superoxide anion radical generated in xanthine–xanthine oxidase system (IC502.4 mg ml−1) and hydroxyl radical generated in Fenton reaction system (IC503.6 mg ml−1). In conclusion, FBD was a distinct antioxidant phytotherapy to rescue neuronal oxidative stress, through blocking LPO, restoring endogenous antioxidant system, but not scavenging free radicals.

scholarly journals An in Vitro and in Vivo Study of the Effect of Dexamethasone on Immunoinhibitory Function of Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells

2018 ◽  
Vol 27 (9) ◽  
pp. 1340-1351 ◽  
Author(s):  
Dan Wang ◽  
Yue-Qi Sun ◽  
Wen-Xiang Gao ◽  
Xing-Liang Fan ◽  
Jian-Bo Shi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Airway Inflammation ◽  
Pluripotent Stem Cell ◽  
Allergic Airway Inflammation ◽  
Induced Pluripotent Stem Cell ◽  
Induced Pluripotent ◽  
Immunomodulatory Function

Induced pluripotent stem cell-derived mesenchymal stem cells (iPSC-MSCs) represent a promising cell source for patient-specific cell therapy. We previously demonstrated that they display an immunomodulatory effect on allergic airway inflammation. Glucocorticoids are powerful anti-inflammatory compounds and widely used in the therapy of allergic diseases. However, the effect of glucocorticoids on the immunomodulatory function of iPSC-MSCs remains unknown. This study aimed to determine the effect of dexamethasone (Dex) on the immunomodulatory function of iPSC-MSCs in vitro and in vivo. A total of three human iPSC-MSC clones were generated from amniocyte-derived iPSCs. Anti-CD3/CD28-induced peripheral blood mononuclear cell (PBMC) proliferation was used to assess the effect of Dex on the immunoinhibitory function of iPSC-MSCs in vitro. Mouse models of contact hypersensitivity (CHS) and allergic airway inflammation were induced, and the levels of inflammation in mice were analyzed with the treatments of iPSC-MSCs and Dex, alone and combined. The results showed that Dex did not interfere with the immunoinhibitory effect of iPSC-MSCs on PBMC proliferation. In CHS mice, simultaneous treatment with Dex did not affect the effect of iPSC-MSCs on the inflammation, both in regional draining lymph nodes and in inflamed ear tissue. In addition, co-administration of iPSC-MSCs with Dex decreased the local expression of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the ears of CHS mice. In the mouse model of allergic airway inflammation, iPSC-MSC treatment combined with Dex resulted in a similar extent of reduction in pulmonary inflammation as iPSC-MSCs or Dex treatment alone. In conclusion, Dex does not significantly affect the immunomodulatory function of iPSC-MSCs both in vitro and in vivo. These findings may have implications when iPSC-MSCs and glucocorticoids are co-administered.

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