The Responses of Bioactive Betanin Pigment and Its Derivatives from a Red Beetroot (Beta vulgaris L.) Betalain-Rich Extract to Hypochlorous Acid

Neutrophils produce hypochlorous acid (HOCl) as well as other reactive oxygen species as part of a natural innate immune response in the human body; however, excessive levels of HOCl can ultimately be detrimental to health. Recent reports suggest that betacyanin plant pigments can act as potent scavengers of inflammatory factors and are notably effective against HOCl. Comparison of the in vitro anti-hypochlorite activities of a novel betalain-rich red beetroot (Beta vulgaris L.) extract with its pure betalainic pigments revealed that the extract had the highest anti-hypochlorite activity, far exceeding the activity of all of the betalainic derivatives and selected reference antioxidants. This suggests that it may be an important food-based candidate for management of inflammatory conditions induced by excessive HOCl production. Among all pigments studied, betanidin exhibited the highest activity across the pH range.

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In VitroExperimental Model of Trained Innate Immunity in Human Primary Monocytes

Clinical and Vaccine Immunology ◽

10.1128/cvi.00349-16 ◽

2016 ◽

Vol 23 (12) ◽

pp. 926-933 ◽

Cited By ~ 96

Author(s):

Siroon Bekkering ◽

Bastiaan A. Blok ◽

Leo A. B. Joosten ◽

Niels P. Riksen ◽

Reinout van Crevel ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Innate Immunity ◽

Reactive Oxygen ◽

Innate Immune ◽

Oxygen Species ◽

Optimal Conditions ◽

Trained Immunity ◽

Training Interval ◽

Resting Time

ABSTRACTInnate immune memory, or trained immunity, has recently been described to be an important property of cells of the innate immune system. Due to the increased interest in this important new field of immunological investigation, we sought to determine the optimal conditions for anin vitroexperimental protocol of monocyte training using three of the most commonly used training stimuli from the literature: β-glucan, the bacillus Calmette-Guérin (BCG) vaccine, and oxidized low-density lipoprotein (oxLDL). We investigated and optimized a protocol of monocyte trained immunity induced by an initial training period with β-glucan, BCG, or oxLDL, followed by washing and resting of the cells and, thereafter, restimulation with secondary bacterial stimuli. The training and resting time intervals were varied to identify the optimal setting for the long-term induction of trained immunity. Trained immunity was assessed in terms of the secondary cytokine response, the production of reactive oxygen species, cell morphology, and induction of glycolysis. Monocytes primed with β-glucan, BCG, and oxLDL showed increased pro- and anti-inflammatory cytokine responses upon restimulation with nonrelated stimuli. Also, all three stimuli induced a switch to glycolysis (the Warburg effect). These effects were most pronounced when the training interval was 24 h and the resting time interval was 6 days. Training with BCG and oxLDL also led to the increased production of reactive oxygen species, whereas training with β-glucan led to the decreased production of reactive oxygen species. We describe the optimal conditions for anin vitroexperimental model with human primary monocytes for study of the induction of trained innate immunity by microbial and metabolic stimuli.

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Exosomes derived from mesenchymal stem cells inhibit catabolism in human chondrocytes by activating autophagy via inhibition of the NF-κB pathway

10.21203/rs.3.rs-83574/v1 ◽

2020 ◽

Author(s):

Jian-Fa Wang ◽

Zhi Zhu ◽

Lei Sun ◽

Shi-kun Shao ◽

Bao-dong Ma ◽

...

Keyword(s):

Electron Microscopy ◽

Primary Cultures ◽

Human Chondrocytes ◽

Inflammatory Factors ◽

Human Umbilical Cord ◽

Adult Males ◽

New Therapeutic Approaches ◽

Inflammatory Conditions ◽

Tnf Α

Abstract Objective: We aimed to determine the significance of MSC-derived exosomes (MSC-Exos) in chondrocyte autophagy under normal and inflammatory conditions.Design: Human umbilical cord-derived MSCs (hMSCs) were cultured in vitro. hMSC-Exos( EX） were isolated by an ultracentrifugation method. Transmission electron microscopy and western analysis were used to identify exosomes. Human chondrocytes were extracted from five adult males with OA undergoing total knee arthroplasty. Primary cultures of chondrocytes from OA patients were stimulated with 50 ng/ml tumor necrosis factor-α (TNF-α) in the presence or absence of hMSC-Exos. Autophagy levels were determined based on expression of autophagic marker LC3, StubRFP-SensGFP-LC3 analysis, and electron microscopy. Catabolic gene and chemokine expression were evaluated using quantitative PCR. The NF-κB inhibitor NS398 was used to analyze the role of the NF-κB pathway in autophagic activation.Results: hMSC-Exos increased LC3-II levels as well as autophagosome number in chondrocytes. hMSC-Exos inhibited TNF-α–induced expression of MMP-3, -9, and -13; ADAMTS5; CCL-2 and -5; and CXCL1. NF-κB inhibition activated autophagy in TNF-α–treated chondrocytes. These results indicate that hMSC-Exos might suppress the levels of catabolic and inflammatory factors in chondrocytes by promoting autophagy via NF-κB pathway inhibition.Conclusions: Our data support the interest in hMSC-Exos to develop new therapeutic approaches for joint conditions.

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Structural Study on Hypochlorous Acid-Mediated Chlorination of Betanin and Its Decarboxylated Derivatives from an Anti-Inflammatory Beta vulgaris L. Extract

Molecules ◽

10.3390/molecules25020378 ◽

2020 ◽

Vol 25 (2) ◽

pp. 378

Author(s):

Agnieszka Kumorkiewicz-Jamro ◽

Karolina Starzak ◽

Katarzyna Sutor ◽

Boris Nemzer ◽

Zbigniew Pietrzkowski ◽

...

Keyword(s):

Structural Study ◽

Electrophilic Substitution ◽

Hypochlorous Acid ◽

High Resolution Mass Spectrometry ◽

Innate Immune ◽

Inflammatory Factors ◽

Response System ◽

Nmr Techniques ◽

Cyclic Intermediate ◽

Resolution Mass

Hypochlorous acid (HOCl) produced by neutrophils is a part of the natural innate immune response system in the human body, but excessive levels of HOCl can ultimately be detrimental to health. Recent reports suggest that betacyanin plant pigments can act as potent scavengers of inflammatory factors and are notably effective against HOCl. In this contribution, chlorination mechanism and position of the electrophilic substitution in betacyanins was studied by high-resolution mass spectrometry and further structural analyses by NMR techniques, which completed the identification of the chlorinated betacyanins. For the study on the influence of the position of decarboxylation on the chlorination mechanism, a comparison of the chlorination position between betanin as well as 17-, and 2,17-decarboxylated betanins was performed. The structural study confirmed that the chlorination position in betanin occurs within the dihydropyridinic moiety at carbon C-18. Therefore, out of the aqueous free chlorine equilibrium species: HOCl, OCl−, Cl2, and Cl2O, the most potent chlorinating agents are HOCl and Cl2O postulated previously and the attack of the Cl⁺ ion on the carbon C-18 with a cyclic intermediate version is considered.

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Tryptophan Metabolites as Scavengers of Reactive Oxygen and Chlorine Species

Pteridines ◽

10.1515/pteridines.2002.13.4.140 ◽

2002 ◽

Vol 13 (4) ◽

pp. 140-143 ◽

Cited By ~ 21

Author(s):

Günter Weiss ◽

Antonio Diez-Ruiz ◽

Christian Murr ◽

Igor Theur ◽

Dietmar Fuchs

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Hypochlorous Acid ◽

Reactive Oxygen ◽

Human Monocyte ◽

Interferon Γ ◽

Oxygen Species ◽

Tryptophan Degradation ◽

Tryptophan Metabolites

Abstract Upon stimulation with interferon-γ, a typical Thl cell-derived cytokine, human monocyte-dertved macrophages produce neopterin derivatives and in parallel degrade the essential amino acid L-tryptophan to L-kynurenine and subsequently to 3-hydroxyanthramlic acid and anthramlic acid. In parallel, stimulated macrophages produce reactive oxygen species such as hydrogen peroxide and hypochlorous acid. Earlier, neopterin and 7.8-dihydroneoptenn were found to enhance or decrease effects of reactive oxygen species in vitro, depending on concentration and on environmental condition. In this study, we investigated the ability of tryptophan and its metabolites to interfere with radicals in vitro by means of a chemiluminiseence-based assay system. When using hydrogen peroxide or chloramine Τ as source for radical formation. L-tryptophan and its catabolites reduced chennluminescence according to a dose-response relationship, 3-hydroxvanthranilic acid being the most efficient compound. Apart from L-kynurenme the scavenging effects of tryptophan and its metabolites were not affected by changes m pH from 5.5 to 7.5. Our data indicate that tryptophan degradation produces metabolites with a high scavenging ability for reactive oxygen and chlorine species, thereby establishing a self-regulatory mechanism to limit the tissue damage by reactive radicals produced by macrophages.

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SKAP2 is required for defense against K. pneumoniae infection and neutrophil respiratory burst

eLife ◽

10.7554/elife.56656 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 1

Author(s):

Giang T Nguyen ◽

Lamyaa Shaban ◽

Matthias Mack ◽

Kenneth D Swanson ◽

Stephen C Bunnell ◽

...

Keyword(s):

Adaptor Protein ◽

Innate Immune ◽

Innate Immune Cells ◽

Ros Production ◽

Oxygen Species ◽

Bacterial Clearance ◽

Pulmonary Infections ◽

Wild Type ◽

Neutrophil Respiratory Burst

Klebsiella pneumoniae is a respiratory, blood, liver, and bladder pathogen of significant clinical concern. We show that the adaptor protein, SKAP2, is required for protection against K. pneumoniae (ATCC 43816) pulmonary infections. Skap2-/- mice had 100-fold higher bacterial burden when compared to wild-type and burden was controlled by SKAP2 expression in innate immune cells. Skap2-/- neutrophils and monocytes were present in infected lungs, and the neutrophils degranulated normally in response to K. pneumoniae infection in mice; however, K. pneumoniae-stimulated reactive oxygen species (ROS) production in vitro was abolished. K. pneumoniae-induced neutrophil ROS response required the activity of SFKs, Syk, Btk, PLCγ2, and PKC. The loss of SKAP2 significantly hindered the K. pneumoniae-induced phosphorylation of SFKs, Syk, and Pyk2 implicating SKAP2 as proximal to their activation in pathogen-signaling pathways. In conclusion, SKAP2-dependent signaling in neutrophils is essential for K. pneumoniae-activated ROS production and for promoting bacterial clearance during infection.

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Virus Mimetic Poly (I:C)-Primed Airway Exosome-like Particles Enter Brain and Induce Inflammatory Cytokines and Mitochondrial Reactive Oxygen Species in Microglia

Biology ◽

10.3390/biology10121359 ◽

2021 ◽

Vol 10 (12) ◽

pp. 1359

Author(s):

Deimantė Kulakauskienė ◽

Deimantė Narauskaitė ◽

Dovydas Gečys ◽

Otilija Juknaitė ◽

Lina Jankauskaitė ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Wistar Rats ◽

Reactive Oxygen ◽

Microglial Cells ◽

Poly I:C ◽

Inflammatory Factors ◽

Oxygen Species ◽

The Brain ◽

Airway Cells

Viral infections induce extracellular vesicles (EVs) containing viral material and inflammatory factors. Exosomes can easily cross the blood-brain barrier during respiratory tract infection and transmit the inflammatory signal to the brain; however, such a hypothesis has no experimental evidence. The study investigated whether exosome-like vesicles (ELVs) from virus mimetic poly (I:C)-primed airway cells enter the brain and interact with brain immune cells microglia. Airway cells were isolated from Wistar rats and BALB/c mice; microglial cell cultures—from Wistar rats. ELVs from poly (I:C)-stimulated airway cell culture medium were isolated by precipitation, visualised by transmission electron microscopy, and evaluated by nanoparticle analyser; exosomal markers CD81 and CD9 were determined by ELISA. For in vitro and in vivo tracking, particles were loaded with Alexa Fluor 555-labelled RNA. Intracellular reactive oxygen species (ROS) were evaluated by DCFDA fluorescence and mitochondrial superoxide—by MitoSOX. ELVs from poly (I:C)-primed airway cells entered the brain within an hour after intranasal introduction, were internalised by microglia and induced intracellular and intramitochondrial ROS production. There was no ROS increase in microglial cells was after treatment with ELVs from airway cells untreated with poly (I:C). In addition, poly (I:C)-primed airway cells induced inflammatory cytokine expression in the brain. The data indicate that ELVs secreted by virus-primed airway cells might enter the brain, cause the activation of microglial cells and neuroinflammation.

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Virus Mimetic Poly (I:C)-Primed Airway Exosomes Enter Brain and Induce Mitochondrial Reactive Oxygen Species in Microglia

10.20944/preprints202107.0356.v1 ◽

2021 ◽

Author(s):

Deimantė Kulakauskienė ◽

Deimantė Narauskaitė ◽

Dovydas Gečys ◽

Otilija Juknaitė ◽

Lina Jankauskaitė ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Wistar Rats ◽

Reactive Oxygen ◽

Microglial Cells ◽

Poly I:C ◽

Inflammatory Factors ◽

Oxygen Species ◽

The Brain ◽

Airway Cells

Viral infections induce exosomes containing viral material and inflammatory factors. During respiratory tract infection, exosomes can easily cross the blood-brain barrier and transmit the inflammatory signal to the brain; however, such a hypothesis has no experimental evidence. The study investigated whether exosomes from virus mimetic poly (I:C)-primed airway cells enter the brain and interact with brain immune cells microglia. Airway cells were isolated from Wistar rats and BALB/c mice; microglial cell cultures - from Wistar rats. Exosomes from poly (I:C)-stimulated airway cell culture medium were isolated by precipitation, visualised by transmission electron microscopy, and evaluated by nanoparticle analyser; exosomal markers CD81 and CD9 were determined by ELISA. For in vitro and in vivo tracking, exosomes were loaded with Alexa Fluor 555-labelled RNA. Intracellular reactive oxygen species (ROS) were evaluated by DCFDA fluo-rescence and mitochondrial superoxide - by MitoSOX. The exosomes from poly (I:C)-primed airway cells entered the brain within an hour after intranasal introduction, were internalised by microglia, and induced intracellular and intramitochondrial ROS production. There was no ROS increase in microglial cells was after treatment with exosomes from airway cells untreated with poly (I:C). The data indicate that virus-primed airway cell exosomes might enter the brain and induce the activation of microglial cells.

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Phospholipases and Reactive Oxygen Species Derived Lipid Biomarkers in Healthy and Diseased Humans and Animals – A Focus on Lysophosphatidylcholine

Frontiers in Physiology ◽

10.3389/fphys.2021.732319 ◽

2021 ◽

Vol 12 ◽

Author(s):

Kathrin M. Engel ◽

Jürgen Schiller ◽

Christina E. Galuska ◽

Beate Fuchs

Keyword(s):

Reactive Oxygen Species ◽

Reactive Oxygen ◽

Lipid Biomarkers ◽

Spectroscopic Methods ◽

Oxygen Species ◽

Inflammatory Conditions ◽

Short Summary ◽

Unsaturated Acyl

Phospholipids (PL) are converted into lipid biomarkers by the action of phospholipases and reactive oxygen species (ROS), which are activated or released under certain physiological and pathophysiological conditions. Therefore, the in vivo concentration of such lipid biomarkers [e.g., lysophospholipids (LPLs)] is altered in humans and animals under different conditions such as inflammation, stress, medication, and nutrition. LPLs are particularly interesting because they are known to possess pro- and anti-inflammatory properties and may be generated by two different pathways: either by the influence of phospholipase A2 or by different reactive oxygen species that are generated in significant amounts under inflammatory conditions. Both lead to the cleavage of unsaturated acyl residues. This review provides a short summary of the mechanisms by which lipid biomarkers are generated under in vitro and in vivo conditions. The focus will be on lysophosphatidylcholine (LPC) because usually, this is the LPL species which occurs in the highest concentration and is, thus, easily detectable by chromatographic and spectroscopic methods. Finally, the effects of lipid biomarkers as signaling molecules and their roles in different human and animal pathologies such as infertility, cancer, atherosclerosis, and aging will be shortly discussed.

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Designed PKC-targeting bryostatin analogs modulate innate immunity and neuroinflammation

10.1101/2020.09.12.294918 ◽

2020 ◽

Author(s):

Efrat Abramson ◽

Clayton Hardman ◽

Akira Shimizu ◽

Soonmyung Hwang ◽

Lynda D. Hester ◽

...

Keyword(s):

Innate Immunity ◽

Innate Immune ◽

Bryostatin 1 ◽

Neurologic Diseases ◽

Drug Candidates ◽

Inflammatory Conditions ◽

The Central Nervous System ◽

Scalable Synthesis

SUMMARYNeuroinflammation characterizes multiple neurologic diseases, including primary inflammatory conditions such as multiple sclerosis (MS) and classical neurodegenerative diseases. Aberrant activation of the innate immune system contributes to disease progression in these conditions, but drugs that modulate innate immunity, particularly within the central nervous system (CNS), are lacking. The CNS-pene-trant natural product bryostatin-1 (bryo-1) attenuates neuroinflammation by targeting innate myeloid cells. Supplies of natural bryo-1 are limited but a recent scalable synthesis has enabled access to it and its analogs (termed bryologs), the latter providing a path to more efficacious, better tolerated, and more accessible agents. Here, we show that multiple synthetically accessible bryologs replicate the anti-inflammatory effects of bryo-1 on innate immune cells in vitro, and a lead bryolog attenuates neuroinflammation in vivo – actions mechanistically dependent on PKC binding. Our findings identify bryologs as promising drug candidates for targeting innate immunity in neuroinflammation and create a platform for evaluation of synthetic PKC modulators in neuroinflammatory diseases such as MS.Graphical Abstract

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Thawed Mesenchymal Stem Cell Product Shows Comparable Immunomodulatory Potency to Cultured Cells In Vitro and in Polymicrobial Septic Animals

Scientific Reports ◽

10.1038/s41598-019-54462-x ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Yuan Tan ◽

Mahmoud Salkhordeh ◽

Jia-Pey Wang ◽

Andrea McRae ◽

Luciana Souza-Moreira ◽

...

Keyword(s):

Cultured Cells ◽

Inflammatory Diseases ◽

Endothelial Permeability ◽

Innate Immune ◽

Activated T Cells ◽

Inflammatory Conditions ◽

Significant Difference ◽

Stem Cell Product

AbstractMesenchymal stem cells (MSCs) have been shown to exert immunomodulatory effects in both acute and chronic diseases. In acute inflammatory conditions like sepsis, cell therapy must be administered within hours of diagnosis, requiring “off-the-shelf” cryopreserved allogeneic cell products. However, their immunomodulatory potency, particularly in abilities to modulate innate immune cells, has not been well documented. Herein we compared the stabilities and functionalities of cultured versus thawed, donor-matched MSCs in modulating immune responses in vitro and in vivo. Cultured and thawed MSCs exhibited similar surface marker profiles and viabilities at 0 hr; however, thawed MSCs exhibited higher levels of apoptotic cells beyond 4 hrs. In vitro potency assays showed no significant difference between the abilities of both MSCs (donor-matched) to suppress proliferation of activated T cells, enhance phagocytosis of monocytes, and restore endothelial permeability after injury. Most importantly, in animals with polymicrobial sepsis, both MSCs significantly improved the phagocytic ability of peritoneal lavage cells, and reduced plasma levels of lactate and selected inflammatory cytokines without significant difference between groups. These results show comparable in vitro and in vivo immunomodulatory efficacy of thawed and fresh MSC products, providing further evidence for the utility of a cryopreserved MSC product for acute inflammatory diseases.

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