Upregulation of Peroxiredoxin 3 Protects Afg3l2-KO Cortical Neurons In Vitro from Oxidative Stress: A Paradigm for Neuronal Cell Survival under Neurodegenerative Conditions

Several neurodegenerative disorders exhibit selective vulnerability, with subsets of neurons more affected than others, possibly because of the high expression of an altered gene or the presence of particular features that make them more susceptible to insults. On the other hand, resilient neurons may display the ability to develop antioxidant defenses, particularly in diseases of mitochondrial origin, where oxidative stress might contribute to the neurodegenerative process. In this work, we investigated the oxidative stress response of embryonic fibroblasts and cortical neurons obtained from Afg3l2-KO mice. AFG3L2 encodes a subunit of a protease complex that is expressed in mitochondria and acts as both quality control and regulatory enzyme affecting respiration and mitochondrial dynamics. When cells were subjected to an acute oxidative stress protocol, the survival of AFG3L2-KO MEFs was not significantly influenced and was comparable to that of WT; however, the basal level of the antioxidant molecule glutathione was higher. Indeed, glutathione depletion strongly affected the viability of KO, but not of WT MEF, thereby indicating that oxidative stress is more elevated in KO MEF even though well controlled by glutathione. On the other hand, when cortical KO neurons were put in culture, they immediately appeared more vulnerable than WT to the acute oxidative stress condition, but after few days in vitro, the situation was reversed with KO neurons being more resistant than WT to acute stress. This compensatory, protective competence was not due to the upregulation of glutathione, rather of two mitochondrial antioxidant proteins: superoxide dismutase 2 and, at an even higher level, peroxiredoxin 3. This body of evidence sheds light on the capability of neurons to activate neuroprotective pathways and points the attention to peroxiredoxin 3, an antioxidant enzyme that might be critical for neuronal survival also in other disorders affecting mitochondria.

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Evaluation of the Effects of Fucoidans from Fucus Species and Laminaria hyperborea against Oxidative Stress and Iron-Dependent Cell Death

Marine Drugs ◽

10.3390/md19100557 ◽

2021 ◽

Vol 19 (10) ◽

pp. 557

Author(s):

Philipp Dörschmann ◽

Sarah Apitz ◽

Inga Hellige ◽

Sandesh Neupane ◽

Susanne Alban ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Cortical Neurons ◽

Algal Species ◽

Neuronal Cell ◽

Glutathione Depletion ◽

Brain Diseases ◽

Laminaria Hyperborea ◽

Beneficial Effects ◽

Protein Levels

Fucoidans are algal polysaccharides that exhibit protective properties against oxidative stress. The aim of this study was to investigate different fucoidans from brown seaweeds for their ability to protect against iron-dependent oxidative stress (ferroptosis), a main hallmark of retinal and brain diseases, including hemorrhage. We investigated five new high-molecular weight fucoidan extracts from Fucus vesiculosus, F. serratus, and F. distichus subsp. evanescens, a previously published Laminaria hyperborean extract, and commercially available extracts from F. vesiculosus and Undaria pinnatifida. We induced oxidative stress by glutathione depletion (erastin) and H2O2 in four retinal and neuronal cell lines as well as primary cortical neurons. Only extracts from F. serratus, F. distichus subsp. evanescens, and Laminaria hyperborea were partially protective against erastin-induced cell death in ARPE-19 and OMM-1 cells, while none of the extracts showed beneficial effects in neuronal cells. Protective fucoidans also attenuated the decrease in protein levels of the antioxidant enzyme GPX4, a key regulator of ferroptosis. This comprehensive analysis demonstrates that the antioxidant abilities of fucoidans may be cell type-specific, besides depending on the algal species and extraction method. Future studies are needed to further characterize the health-benefiting effects of fucoidans and to determine the exact mechanism underlying their antioxidative abilities.

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Neutrophil Extracellular Traps Induced in Rheumatoid Arthritis Conditioned Animals are Inhibited Through Selenium Nanoparticles Supplementation

10.21203/rs.3.rs-41615/v1 ◽

2020 ◽

Author(s):

Bo Zhang ◽

Xiao-Xiong Zhao ◽

Yuan Lin ◽

Tong Chen ◽

Ren Shi-Xiang

Keyword(s):

Rheumatoid Arthritis ◽

Oxidative Stress ◽

Human Study ◽

Neutrophil Extracellular Traps ◽

The Other ◽

Antioxidant Enzyme Activities ◽

Experimental Conditions ◽

Extracellular Traps ◽

Other Hand

Abstract Growing experimental evidence shows that the neutrophil extracellular traps (NETs) plays vital contribution in rheumatoid arthritis (RA). Selenium (Se) and Se nanoparticles (SeNPs) known to modulate RA-induced pathogenesis through antioxidant gene modulation. In the present study we have inferred that SeNPs supplementation effectively controls NETs formation, which in turn could curtail RA-induced inflammatory response.Neutrophils obtained from different experimental conditions were used to evaluate the in vitro NETs formation and inhibition of through SeNPs supplementation. Increased oxidative stress, decreased antioxidant enzyme activities and increased inflammatory cytokines were observed in neutrophils of RA, whereas SeNPs treatment attenuate it. Neutrophils obtained from control and SeNPs supplemented groups do not have statistically significant Se level between the groups, on the other hand reduced the oxidative stress. Neutrophils of RA forms more spontaneous NETs in vitro culture than that of control and SeNPs treated neutrophils. Neutrophils obtained from RA rats are more inclined for external NETs inducing agent such as lipopolysaccharides and phorbol 12-myristate 13-acetate, when compared with SeNPs treated and control neutrophils. On the other hand in vitro pre-treatment of neutrophils with SeNPs before exposing to NETs inducing substances, indicate the anti-NETs forming property of SeNPs. This effect could be mediated through reduction in major inflammatory mediators namely TNF-α, IL-17 and IL-6. This findings confirms that SeNPs could act as effective NETs formation blocking agent. Our present and previous observation conclude that SeNPs, could serve as an effective anti-arthritic agent warranting human study. Furthermore, this study also throws light on the new information such as SeNPs which could be used as therapeutics agent, where NETs is major pathogenic factor.

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EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

Acta Endocrinologica ◽

10.1530/acta.0.0770064 ◽

1974 ◽

Vol 77 (1) ◽

pp. 64-70 ◽

Cited By ~ 9

Author(s):

Gustav Wägar

Keyword(s):

Protein Synthesis ◽

Actinomycin D ◽

The Other ◽

Leucine Incorporation ◽

Short Term ◽

Other Hand ◽

Thyroid Glands ◽

Translational Level ◽

Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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Oxytocin analogues with non-coded amino acid residues in position 8: [8-Neopentylglycine]oxytocin and [8-cycloleucine]oxytocin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19872317 ◽

1987 ◽

Vol 52 (9) ◽

pp. 2317-2325 ◽

Cited By ~ 5

Author(s):

Jan Hlaváček ◽

Jan Pospíšek ◽

Jiřina Slaninová ◽

Walter Y. Chan ◽

Victor J. Hruby

Keyword(s):

Amino Acid ◽

Solid Phase Synthesis ◽

Solid Phase ◽

The Other ◽

Amino Acid Residues ◽

Phase Synthesis ◽

Other Hand ◽

Fragment Condensation

[8-Neopentylglycine]oxytocin (II) and [8-cycloleucine]oxytocin (III) were prepared by a combination of solid-phase synthesis and fragment condensation. Both analogues exhibited decreased uterotonic potency in vitro, each being about 15-30% that of oxytocin. Analogue II also displayed similarly decreased uterotonic potency in vivo and galactogogic potency. On the other hand, analogue III exhibited almost the same potency as oxytocin in the uterotonic assay in vivo and in the galactogogic assay.

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Peroxidases from Tulip Bulbs (Tulipa fosteriana, L.) Oxidize Xenobiotics NNitrosodimethylamine and N-Nitroso-N-methylaniline in vitro

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19971804 ◽

1997 ◽

Vol 62 (11) ◽

pp. 1804-1814 ◽

Cited By ~ 3

Author(s):

Marie Stiborová ◽

Hana Hansíková

Keyword(s):

Cytochromes P450 ◽

Kinetic Studies ◽

The Other ◽

Maximal Velocity ◽

Michaelis Constant ◽

Other Hand ◽

Plant Peroxidases ◽

Tulip Bulbs

Tulip bulbs (Tulipa fosteriana, L.) contain peroxidases catalyzing the oxidation of the xenobiotics N-nitrosodimethylamine (NDMA) and N-nitroso-N-methylaniline (NMA). Three anionic (A1, A2, A3) and four cationic (B, C, D, E) peroxidases were purified from this tissue, partially characterized and used for kinetic studies. Demethylation of NDMA and NMA producing formaldehyde is catalyzed by one anionic (A1) and three cationic (C, D, E) peroxidases. The oxidation of NDMA by tulip peroxidases exhibits the Michaelis-Menten kinetics. The apparent Michaelis constant and the maximal velocity values for this substrate were determined. On the other hand, non-Michaelian kinetics for the NMA oxidation were observed with tulip peroxidases. The most abundant cationic peroxidase (peroxidase C) was used for detailed enzymatic studies. In addition to formation of formaldehyde, methylaniline, aniline, 4-aminophenol and phenol were found to be metabolites formed from NMA. Phenol was formed presumably by N-demethylation via a benzenediazonium ion, while methylaniline, aniline and 4-aminophenol were products of denitrosation of the substrate. The efficiencies of plant peroxidases to oxidize NDMA and NMA in vitro are compared with those of cytochromes P450 and discussed.

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Fetal erythropoiesis in steel mutant mice. III. Defect in differentiation from BFU-E to CFU-E during early development

Blood ◽

10.1182/blood.v51.3.539.539 ◽

1978 ◽

Vol 51 (3) ◽

pp. 539-547 ◽

Cited By ~ 18

Author(s):

DH Chui ◽

SK Liao ◽

K Walker

Keyword(s):

Progenitor Cells ◽

Early Development ◽

The Other ◽

Mutant Mice ◽

Erythroid Progenitor ◽

Erythroid Progenitor Cells ◽

Other Hand ◽

Colony Forming Units ◽

Fetal Erythropoiesis

Abstract Erythroid progenitor cells in +/+ and Sl/Sld fetal livers manifested as burst-forming units-erythroid (BFU-E) and colony-forming units- erythroid (CFU-E) were assayed in vitro during early development. The proportion of BFU-E was higher as mutant than in normal fetal livers. On the other hand, the proportion of CFU-E was less in the mutant than in the normal. These results suggest that the defect in Sl/Sld fetal hepatic erythropoiesis is expressed at the steps of differentiation that effect the transition from BFU-E to CFU-E.

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Machine learning-based classification of mitochondrial morphology in primary neurons and brain

Scientific Reports ◽

10.1038/s41598-021-84528-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Garrett M. Fogo ◽

Anthony R. Anzell ◽

Kathleen J. Maheras ◽

Sarita Raghunayakula ◽

Joseph M. Wider ◽

...

Keyword(s):

Image Analysis ◽

Cortical Neurons ◽

Mitochondrial Dynamics ◽

Automated Image Analysis ◽

Mitochondrial Morphology ◽

Analysis Pipeline ◽

Genetic Ablation ◽

Block Face

AbstractThe mitochondrial network continually undergoes events of fission and fusion. Under physiologic conditions, the network is in equilibrium and is characterized by the presence of both elongated and punctate mitochondria. However, this balanced, homeostatic mitochondrial profile can change morphologic distribution in response to various stressors. Therefore, it is imperative to develop a method that robustly measures mitochondrial morphology with high accuracy. Here, we developed a semi-automated image analysis pipeline for the quantitation of mitochondrial morphology for both in vitro and in vivo applications. The image analysis pipeline was generated and validated utilizing images of primary cortical neurons from transgenic mice, allowing genetic ablation of key components of mitochondrial dynamics. This analysis pipeline was further extended to evaluate mitochondrial morphology in vivo through immunolabeling of brain sections as well as serial block-face scanning electron microscopy. These data demonstrate a highly specific and sensitive method that accurately classifies distinct physiological and pathological mitochondrial morphologies. Furthermore, this workflow employs the use of readily available, free open-source software designed for high throughput image processing, segmentation, and analysis that is customizable to various biological models.

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Mitochondrial fission and mitophagy are independent mechanisms regulating ischemia/reperfusion injury in primary neurons

Cell Death and Disease ◽

10.1038/s41419-021-03752-2 ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Anthony R. Anzell ◽

Garrett M. Fogo ◽

Zoya Gurm ◽

Sarita Raghunayakula ◽

Joseph M. Wider ◽

...

Keyword(s):

Cortical Neurons ◽

Ischemia Reperfusion Injury ◽

Mitochondrial Dynamics ◽

Ischemia Reperfusion ◽

Mitochondrial Fission ◽

Conditional Knockout ◽

Mitochondrial Morphology ◽

Primary Neurons ◽

Mitochondrial Fragmentation

AbstractMitochondrial dynamics and mitophagy are constitutive and complex systems that ensure a healthy mitochondrial network through the segregation and subsequent degradation of damaged mitochondria. Disruption of these systems can lead to mitochondrial dysfunction and has been established as a central mechanism of ischemia/reperfusion (I/R) injury. Emerging evidence suggests that mitochondrial dynamics and mitophagy are integrated systems; however, the role of this relationship in the context of I/R injury remains unclear. To investigate this concept, we utilized primary cortical neurons isolated from the novel dual-reporter mitochondrial quality control knockin mice (C57BL/6-Gt(ROSA)26Sortm1(CAG-mCherry/GFP)Ganl/J) with conditional knockout (KO) of Drp1 to investigate changes in mitochondrial dynamics and mitophagic flux during in vitro I/R injury. Mitochondrial dynamics was quantitatively measured in an unbiased manner using a machine learning mitochondrial morphology classification system, which consisted of four different classifications: network, unbranched, swollen, and punctate. Evaluation of mitochondrial morphology and mitophagic flux in primary neurons exposed to oxygen-glucose deprivation (OGD) and reoxygenation (OGD/R) revealed extensive mitochondrial fragmentation and swelling, together with a significant upregulation in mitophagic flux. Furthermore, the primary morphology of mitochondria undergoing mitophagy was classified as punctate. Colocalization using immunofluorescence as well as western blot analysis revealed that the PINK1/Parkin pathway of mitophagy was activated following OGD/R. Conditional KO of Drp1 prevented mitochondrial fragmentation and swelling following OGD/R but did not alter mitophagic flux. These data provide novel evidence that Drp1 plays a causal role in the progression of I/R injury, but mitophagy does not require Drp1-mediated mitochondrial fission.

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Neurotherapeutic Effect of Inula britannica var. Chinensis against H2O2-Induced Oxidative Stress and Mitochondrial Dysfunction in Cortical Neurons

Antioxidants ◽

10.3390/antiox10030375 ◽

2021 ◽

Vol 10 (3) ◽

pp. 375

Author(s):

Jin Young Hong ◽

Hyunseong Kim ◽

Junseon Lee ◽

Wan-Jin Jeon ◽

Seung Ho Baek ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Cortical Neurons ◽

Inflammatory Diseases ◽

Neuroprotective Effect ◽

Neuroprotective Effects ◽

Neuronal Viability ◽

Inula Britannica ◽

Oxidative Effects

Inula britannica var. chinensis (IBC) has been used as a traditional medicinal herb to treat inflammatory diseases. Although its anti-inflammatory and anti-oxidative effects have been reported, whether IBC exerts neuroprotective effects and the related mechanisms in cortical neurons remain unknown. In this study, we investigated the effects of different concentrations of IBC extract (5, 10, and 20 µg/mL) on cortical neurons using a hydrogen peroxide (H2O2)-induced injury model. Our results demonstrate that IBC can effectively enhance neuronal viability under in vitro-modeled reaction oxygen species (ROS)-generating conditions by inhibiting mitochondrial ROS production and increasing adenosine triphosphate level in H2O2-treated neurons. Additionally, we confirmed that neuronal death was attenuated by improving the mitochondrial membrane potential status and regulating the expression of cytochrome c, a protein related to cell death. Furthermore, IBC increased the expression of brain-derived neurotrophic factor and nerve growth factor. Furthermore, IBC inhibited the loss and induced the production of synaptophysin, a major synaptic vesicle protein. This study is the first to demonstrate that IBC exerts its neuroprotective effect by reducing mitochondria-associated oxidative stress and improving mitochondrial dysfunction.

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THE PATHOLOGIC EFFECTS OF STREPTOCOCCI FROM CASES OF POLIOMYELITIS AND OTHER SOURCES

Journal of Experimental Medicine ◽

10.1084/jem.25.4.557 ◽

1917 ◽

Vol 25 (4) ◽

pp. 557-580 ◽

Cited By ~ 25

Author(s):

Carroll G. Bull

Keyword(s):

Spinal Cord ◽

Guinea Pigs ◽

The Other ◽

Laboratory Animals ◽

Histological Changes ◽

Other Hand ◽

Brain And Spinal Cord ◽

The Brain

Streptococci cultivated from the tonsils of thirty-two cases of poliomyelitis were used to inoculate various laboratory animals. In no case was a condition induced resembling poliomyelitis clinically or pathologically in guinea pigs, dogs, cats, rabbits, or monkeys. On the other hand, a considerable percentage of the rabbits and a smaller percentage of some of the other animals developed lesions due to streptococci. These lesions consisted of meningitis, meningo-encephalitis, abscess of the brain, arthritis, tenosynovitis, myositis, abscess of the kidney, endocarditis, pericarditis, and neuritis. No distinction in the character or frequency of the lesions could be determined between the streptococci derived from poliomyelitic patients and from other sources. Streptococci isolated from the poliomyelitic brain and spinal cord of monkeys which succumbed to inoculation with the filtered virus failed to induce in monkeys any paralysis or the characteristic histological changes of poliomyelitis. These streptococci are regarded as secondary bacterial invaders of the nervous organs. Monkeys which have recovered from infection with streptococci derived from cases of poliomyelitis are not protected from infection with the filtered virus, and their blood does not neutralize the filtered virus in vitro. We have failed to detect any etiologic or pathologic relationship between streptococci and epidemic poliomyelitis in man or true experimental poliomyelitis in the monkey.

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