scholarly journals CG8005 Mediates Transit-Amplifying Spermatogonial Divisions via Oxidative Stress in Drosophila Testes

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Wanyin Chen ◽  
Xiaojin Luan ◽  
Yidan Yan ◽  
Min Wang ◽  
Qianwen Zheng ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Stem Cell ◽  
Mrna Expression ◽  
Genetic Manipulation ◽  
Redox Homeostasis ◽  
Cell Activity ◽  
Ros Generation ◽  
S2 Cells ◽  
Key Factor

The generation of reactive oxygen species (ROS) widely occurs in metabolic reactions and affects stem cell activity by participating in stem cell self-renewal. However, the mechanisms of transit-amplifying (TA) spermatogonial divisions mediated by oxidative stress are not fully understood. Through genetic manipulation of Drosophila testes, we demonstrated that CG8005 regulated TA spermatogonial divisions and redox homeostasis. Using in vitro approaches, we showed that the knockdown of CG8005 increased ROS levels in S2 cells; the induced ROS generation was inhibited by NAC and exacerbated by H2O2 pretreatments. Furthermore, the silencing of CG8005 increased the mRNA expression of oxidation-promoting factors Keap1, GstD1, and Mal-A6 and decreased the mRNA expression of antioxidant factors cnc, Gclm, maf-S, ND-42, and ND-75. We further investigated the functions of the antioxidant factor cnc, a key factor in the Keap1-cnc signaling pathway, and showed that cnc mimicked the phenotype of CG8005 in both Drosophila testes and S2 cells. Our results indicated that CG8005, together with cnc, controlled TA spermatogonial divisions by regulating oxidative stress in Drosophila.

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.

Protocatechuic Acid Protects Platelets from Apoptosis via Inhibiting Oxidative Stress-Mediated PI3K/Akt/GSK3β Signaling

2021 ◽  
Author(s):  
Fuli Ya ◽  
Kongyao Li ◽  
Hong Chen ◽  
Zezhong Tian ◽  
Die Fan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Caspase 3 ◽  
Protocatechuic Acid ◽  
Human Platelets ◽  
Ros Generation ◽  
Inhibitory Effects ◽  
Platelet Apoptosis ◽  
Phosphatidylserine Exposure ◽  
Underlying Mechanisms

AbstractOxidative stress plays crucial roles in initiating platelet apoptosis that facilitates the progression of cardiovascular diseases (CVDs). Protocatechuic acid (PCA), a major metabolite of anthocyanin cyanidin-3-O-β-glucoside (Cy-3-g), exerts cardioprotective effects. However, underlying mechanisms responsible for such effects remain unclear. Here, we investigate the effect of PCA on platelet apoptosis and the underlying mechanisms in vitro. Isolated human platelets were treated with hydrogen peroxide (H2O2) to induce apoptosis with or without pretreatment with PCA. We found that PCA dose-dependently inhibited H2O2-induced platelet apoptosis by decreasing the dissipation of mitochondrial membrane potential, activation of caspase-9 and caspase-3, and decreasing phosphatidylserine exposure. Additionally, the distributions of Bax, Bcl-xL, and cytochrome c mediated by H2O2 in the mitochondria and the cytosol were also modulated by PCA treatment. Moreover, the inhibitory effects of PCA on platelet caspase-3 cleavage and phosphatidylserine exposure were mainly mediated by downregulating PI3K/Akt/GSK3β signaling. Furthermore, PCA dose-dependently decreased reactive oxygen species (ROS) generation and the intracellular Ca2+ concentration in platelets in response to H2O2. N-Acetyl cysteine (NAC), a ROS scavenger, markedly abolished H2O2-stimulated PI3K/Akt/GSK3β signaling, caspase-3 activation, and phosphatidylserine exposure. The combination of NAC and PCA did not show significant additive inhibitory effects on PI3K/Akt/GSK3β signaling and platelet apoptosis. Thus, our results suggest that PCA protects platelets from oxidative stress-induced apoptosis through downregulating ROS-mediated PI3K/Akt/GSK3β signaling, which may be responsible for cardioprotective roles of PCA in CVDs.

miR-187 modulates cardiomyocyte apoptosis and oxidative stress in myocardial infarction mice via negatively regulating DYRK2

2021 ◽  
Keyword(s):  
Oxidative Stress ◽  
Myocardial Infarction ◽  
Protective Effect ◽  
Myocardial Infarct ◽  
Annexin V ◽  
Cardiomyocyte Apoptosis ◽  
Ros Generation ◽  
Downstream Target

Myocardial infarction is a serious representation of cardiovescular disease, MicroRNAs play a role in modifying I/R injury and myocardial infarct remodeling. The present study therefore examined the potential role of miR-187 in cardiac I/R injury and its underlying mechanisms. miR-187 was inhibited or overexpressed in cardiomyocytes H/R models by pretreatment with miR-187 mimic or inhibitor to confirm the function of miR-187 in H/R. DYRK2 was inhibited or overexpressed in cardiomyocytes H/R models by pretreatment with DYRK2 inhibitor. A myocardium I/R mouse model was established. Circulating levels of miR-187 or DYRK2 was detected by quantitative realtime PCR and protein expression was detected by western blotting. The cell viability in all groups was determined by MTT assay and the apoptosis ratio was detected by flow cytometry after staining with Annexin V-FITC. The effect of miR-187 on cellular ROS generation was examined by DCFH-DA. The level of lipid peroxidation and SOD expression were determined by MDA and SOD assay. The findings indicated that miR-187 may be a possible regulator in the protective effect of H/R-induced cardiomyocyte apoptosis, cellular oxidative stress and leaded to DYRK2 suppression at a posttranscriptional level. Moreover, the improvement of miR-187 on H/R-induced cardiomyocyte injury contributed to the obstruction of DYRK2 expression. In addition, these results identified DYRK2 as the functional downstream target of miR-187 regulated myocardial infarction and oxidative stress.These present work provided the first insight into the function of miR-187 in successfully protect cardiomyocyte both in vivo and in vitro, and such a protective effect were mediated through the regulation of DYRK2 expression.

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 Detecting Validated Intracellular ROS Generation with 18F-dihydroethidine-Based PET

2021 ◽  
Author(s):  
Edward C. T. Waters ◽  
Friedrich Baark ◽  
Zilin Yu ◽  
Filipa Mota ◽  
Thomas R. Eykyn ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Contractile Function ◽  
Ex Vivo ◽  
Glutathione Depletion ◽  
Ros Generation ◽  
Cardiac Contractile ◽  
Rat Hearts ◽  
Intracellular Ros ◽  
Cardiac Contractile Dysfunction

Abstract Purpose To determine the sensitivity of the 18F-radiolabelled dihydroethidine analogue ([18F]DHE) to ROS in a validated ex vivo model of tissue oxidative stress. Procedures The sensitivity of [18F]DHE to various ROS-generating systems was first established in vitro. Then, isolated rat hearts were perfused under constant flow, with contractile function monitored by intraventricular balloon. Cardiac uptake of infused [18F]DHE (50–150 kBq.min−1) was monitored by γ-detection, while ROS generation was invoked by menadione infusion (0, 10, or 50 μm), validated by parallel measures of cardiac oxidative stress. Results [18F]DHE was most sensitive to oxidation by superoxide and hydroxyl radicals. Normalised [18F]DHE uptake was significantly greater in menadione-treated hearts (1.44 ± 0.27) versus control (0.81 ± 0.07) (p < 0.05, n = 4/group), associated with concomitant cardiac contractile dysfunction, glutathione depletion, and PKG1α dimerisation. Conclusion [18F]DHE reports on ROS in a validated model of oxidative stress where perfusion (and tracer delivery) is unlikely to impact its pharmacokinetics.

scholarly journals Spontaneous induction of an homologous Robertsonian translocation, Rb(11.11) in a murine embryonic stem cell line

1990 ◽  
Vol 55 (2) ◽  
pp. 107-110 ◽  
Author(s):  
John Anthony Crolla ◽  
David Brown ◽  
David G. Whittingham
Keyword(s):  
Stem Cell ◽  
Embryonic Stem Cell ◽  
Recombinant Dna ◽  
Genetic Manipulation ◽  
Embryonic Stem Cell Line ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Transgenic Animals ◽  
Translocation Chromosome

SummaryKaryotype analysis of a series of established mouse embryonic stem cell (MESC) lines showed that the majority were aneuploid by the 7th and 9th passage and that all lines contained a single Robertsonian (Rb) translocation chromosome with a symmetrical, homologous, arm composition Rb(11.11). Although the chromosomal imbalance makes these MESC lines unsuitable for genetic manipulation in vitro and hence for subsequent production of transgenic animals, the spontaneous occurrence and stable retention of the homologous Rb(11.11) as the only metacentric chromosome in an otherwise all acrocentric karyotype, provides potentially useful cell lines for gene assignment and recombinant DNA studies.

scholarly journals In Vitro Derivation and Propagation of Spermatogonial Stem Cell Activity from Mouse Pluripotent Stem Cells

Cell Reports ◽  
2016 ◽  
Vol 17 (10) ◽  
pp. 2789-2804 ◽  
Author(s):  
Yukiko Ishikura ◽  
Yukihiro Yabuta ◽  
Hiroshi Ohta ◽  
Katsuhiko Hayashi ◽  
Tomonori Nakamura ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Pluripotent Stem Cells ◽  
Cell Activity ◽  
Spermatogonial Stem Cell ◽  
Stem Cell Activity

Abstract 6253: Increased Expression of Thioredoxin Interacting Protein Promotes Oxidative Stress and Contributes to the Pathogenesis Of Diabetic Cardiomyopathy

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Kim A Connelly ◽  
Darren J Kelly ◽  
Michael Zhang ◽  
Kerri Thai ◽  
Andrew Advani ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Mrna Expression ◽  
High Glucose ◽  
Diastolic Heart Failure ◽  
Transgenic Rat ◽  
Interacting Protein ◽  
Thioredoxin Interacting Protein ◽  
Neonatal Cardiomyocytes

Background: Alterations in the thioredoxin (TRX) antioxidant system have been implicated in the pathogenesis of cardiac injury, particularly in the diabetic setting. While constitutively present, TRX activity is reduced by the presence of its endogenous inhibitor, thioredoxin interacting protein (TxnIP). We hypothesized that by increasing TxnIP, diabetes may reduce TRX activity and contribute to oxidative stress. Methods: Cell culture studies were performed using the H9C2 rat cardiomyoblast cell line and neonatal cardiomyocytes isolated from 1 day old Sprague Dawley rat neonates. In-vivo studies were performed using a hemodynamically-validated rodent model of diabetic diastolic heart failure, the diabetic (mRen-2)27 transgenic rat (Ren-2). Urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) was used as a measure of oxidative stress. Results: In- vitro, high glucose (25mmol/l) resulted in increased TxnIP mRNA expression in both neonatal cardiomyocytes as well as H92C cells (2.21 ± 0.6 v 1.00 ± 0.19, p<0.05 compared to normoglycaemic conditions) with a 45% reduction in TRX activity (0.11 ± 0.01 v 0.061± 0.003, p<0.01). In-vivo, diabetes led to a 250% rise in TxnIP mRNA expression compared to control (2.54 ± 0.5 v 1.00 ± 0.11, p<0.001) that was accompanied by a three fold rise in urinary 8-OHdG (680 ± 280 v 1395 ± 391 ng/ml, p<0.001). Conclusion: In both the in vitro and in vivo settings, high glucose leads to TxnIP over-expression associated with reduced TRX activity thereby increasing oxidative stress and implicating this system in the pathogenesis of the cardiac dysfunction that characterizes the diabetic state. Pharmacological manipulation of the TRX-TxnIP system may represent a novel target to reduce diabetic complications.

scholarly journals Safflor Yellow B Attenuates Ischemic Brain Injury via Downregulation of Long Noncoding AK046177 and Inhibition of MicroRNA-134 Expression in Rats

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Chaoyun Wang ◽  
Hongzhi Wan ◽  
Qiaoyun Wang ◽  
Hongliu Sun ◽  
Yeying Sun ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Brain Injury ◽  
Ischemia Reperfusion ◽  
Cell Activity ◽  
Neuronal Injury ◽  
The Body ◽  
Ros Generation ◽  
Related Factor ◽  
Cell Respiration ◽  
Oxidative Balance

Stroke breaks the oxidative balance in the body and causes extra reactive oxygen species (ROS) generation, leading to oxidative stress damage. Long noncoding RNAs (lncRNAs) and microRNAs play pivotal roles in oxidative stress-mediated brain injury. Safflor yellow B (SYB) was able to effectively reduce ischemia-mediated brain damage by increasing antioxidant capacity and inhibiting cell apoptosis. In this study, we investigated the putative involvement of lncRNA AK046177 and microRNA-134 (miR-134) regulation in SYB against ischemia/reperfusion- (I/R-) induced neuronal injury. I/R and oxygen-glucose deprivation/reoxygenation (OGD/R) were established in vivo and in vitro. Cerebral infarct volume, neuronal apoptosis, and protein expression were detected. The effects of SYB on cell activity, cell respiration, nuclear factor erythroid 2-related factor 2 (Nrf2), antioxidant enzymes, and ROS were evaluated. I/R or OGD/R upregulated the expression of AK046177 and miR-134 and subsequently inhibited the activation and expression of CREB, which caused ROS generation and brain/cell injury. SYB attenuated the effects of AK046177, inhibited miR-134 expression, and promoted CREB activation, which in turn promoted Nrf2 expression, and then increased antioxidant capacities, improved cell respiration, and reduced apoptosis. We suggested that the antioxidant effects of SYB were driven by an AK046177/miR-134/CREB-dependent mechanism that inhibited this pathway, and that SYB has potential use in reducing or possibly preventing I/R-induced neuronal injury.

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.

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