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

2020 ◽  
Author(s):  
Bo Zhang ◽  
Xiao-Xiong Zhao ◽  
Yuan Lin ◽  
Tong Chen ◽  
Ren Shi-Xiang

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.

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1056.2-1057
Author(s):  
S. Bedina ◽  
E. Mozgovaya ◽  
A. Trofimenko ◽  
S. Spitsina ◽  
M. Mamus

Background:Rheumatoid arthritis (RA) is an autoimmune rheumatic disease of unknown etiology characterized by chronic erosive arthritis and systemic organ involvement resulting in early disability and shorter life expectancy. Neutrophils are suggested to play a substantial role in the induction and promotion of autoimmune inflammation in RA. This ability can be based on newly discovered feature of neutrophils to release neutrophil extracellular traps (NETs) during specific type cell death called NETosis. Hyperproduction of reactive oxygen species (ROS) is one of the factors promoting NETs production. With this background, the study of pro- and antioxidant enzymatic activities in RA patients can be of great interest.Objectives:To assess plasma activities of essential prooxidant and antioxidant enzymes in RA patients.Methods:The research was carried out in agreement with the WMA Declaration of Helsinki principles. 71 RA patients (46 women and 25 men) were enrolled in the study. The diagnosis was verified using ACR/EULAR criteria (2010). RA activity was measured using the Disease Activity Score of 28 joints (DAS28). 30 healthy persons comprise control group. Plasma xanthine oxidase (XO; ЕС 1.17.3.2), xanthine dehydrogenase (XDH; ЕС 1.17.1.4) and superoxide dismutase (SOD; ЕС 1.15.1.1) activities were measured using spectrophotometric technique. XO and XDG activities were expressed as nmol/ml/min, SOD activity – as units of action. Statistical analysis was performed using Statistica 6.0 software package. Differences were considered significant when p<0.05. Reference ranges were calculated as means ±2SD.Results:Mean age of patients was 43.2±3.6 years, mean RA duration was 11.9±2.6 years. 24 (33.8%) RA patients had low disease activity, and 6 (8.5%) patients had high one. Extra-articular manifestations were found in 30 (42.2%) patients. 30% of them had cardiovascular involvement, 23.3% – pulmonary lesions, and 23.3% had renal involvement. Reference ranges for XO, XDG, and SOD activities were 2.28-5.12 nmol/min/ml, 3,96-7,24 nmol/min/ml, and 3,13-6,58 units, respectively. We examined activities of these enzymes in circulation of RA patients with different patterns of clinical manifestations as well as relationship between RA activity and XO, XDG, and SOD activities. RA patients had increased both mean XO and mean SOD activities (p<0.001 for both enzymes). XO activity reached its highest values at maximum disease activity and overt extra-articular involvements, while SOD activity did it in moderate and high disease activities as well as in patients with joint manifestations. XDG activity was increased in low disease activity (р<0.001) and solely joint lesions (р=0.011), while moderate or high disease activities (р=0.008) and extra-articular involvements (р=0.025) were characterized by decreased activity of this enzyme.Conclusion:We have revealed substantial multidirectional changes of plasma XO and XDG activities in RA. Plasma enzymatic pattern in RA patients is characterized by activation of both oxidant and antioxidant metabolic pathways. Activities of XO and SOD were positively correlated with RA activity, while XDG activity was negative correlated with RA activity. The differences between selective articular RA type and RA form with extraarticular manifestations were also revealed. Changes in oxidant and antioxidant enzyme activities can be connected with anticitrulline autoimmunity in RA via production of citrulline-rich neutrophil extracellular traps, thus enhancing rheumatoid autoimmunity.Disclosure of Interests:None declared


2005 ◽  
Vol 68 (3) ◽  
pp. 613-615 ◽  
Author(s):  
DANTE J. BUENO ◽  
LILIANA DI MARCO ◽  
GUILLERMO OLIVER ◽  
ALICIA BARDÓN

Zearalenone (ZEA) is a potent estrogenic metabolite produced by some Fusarium species. No treatment has been successfully employed to get rid of the ZEA contained in foods. This study was conducted to evaluate the ability (adsorptive power) of five adsorbents—activated carbon, bentonite, talc, sandstone, and calcium sulfate—to trap ZEA in vitro. Activated carbon was the best adsorbent, binding 100% ZEA (pH 3 and 7.3) at 0.1, 0.25, 0.5, and 1% dose levels. Bentonite, talc, and calcium sulfate were less efficient than activated carbon but still could bind ZEA to some extent. On the other hand, sandstone was inactive in the experimental conditions employed. Our results indicate that activated carbon could be a good candidate for detoxification of ZEA present in foods.


1960 ◽  
Vol XXXIII (I) ◽  
pp. 59-66 ◽  
Author(s):  
J. van der Vies

ABSTRACT Adrenal function in rats under various experimental conditions was studied by incubating the adrenals in vitro and determining the corticosteroid output during one hour. This in vitro corticoid production was reduced after hypophysectomy, hypothalamus-lesioning and treatment with hydrocortisone or with Nembutal and morphine. On the other hand, an increased production was observed following stimulation of the pituitary-adrenal system by exogenous histamine or corticotrophin. From these experiments it is concluded that the corticoid production in vitro reflects the activity of the adrenal cortex in vivo and hence can be used for the study of the latter function.


2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Barbara Bettegazzi ◽  
Ilaria Pelizzoni ◽  
Floramarida Salerno Scarzella ◽  
Lisa Michelle Restelli ◽  
Daniele Zacchetti ◽  
...  

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.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Adéla Navrátilová ◽  
Viktor Bečvář ◽  
Jiří Baloun ◽  
Dres Damgaard ◽  
Claus Henrik Nielsen ◽  
...  

AbstractS100A11 (calgizzarin), a member of S100 family, is associated with several autoimmune diseases, including rheumatoid arthritis (RA). Neutrophil extracellular traps (NETs) are implicated in the pathogenesis of RA and in the externalization of some S100 family members. Therefore, we aimed to determine the association between S100A11 and NETs in RA. For this purpose, the levels of S100A11 and NETosis markers were detected in the RA synovial fluid by immunoassays. The expression of S100A11 by neutrophils in the RA synovial tissue was assessed. Neutrophils isolated from peripheral blood were exposed to S100A11 or stimulated to release NETs. The levels of NETosis- and inflammation-associated proteins were analysed by immunoassays. NETs were visualized by immunofluorescence. We showed that S100A11 was expressed by the neutrophils in the RA synovial tissue. Moreover, S100A11 in the RA synovial fluid correlated with several NETosis markers. In vitro, S100A11 was abundantly released by neutrophils undergoing NETosis compared to untreated cells (p < 0.001). Extracellular S100A11 increased the secretion of IL-6 (p < 0.05) and TNF (p < 0.05) by neutrophils but did not induce NETosis. This study demonstrates, for the first time, that the release of S100A11 is dependent on NETosis and that extracellular S100A11 augments the inflammatory response by inducing pro-inflammatory cytokines in neutrophils.


2016 ◽  
pp. 66-70
Author(s):  
J. V. Zubkova ◽  
I. A. Novikova ◽  
V. V. Zhelezko

The article presents the results of the assessment of the role of platelets in formation of extracellular traps by neutrophils. We have detected the ability of platelets to oppress the formation of extracellular traps by neutrophils in vitro cultures in patients with rheumatoid arthritis (RA) (n = 42) and systemic lupus erythematosus (SLE) (n = 24), but not in patients with hemorrhagic vasculitis (GW) (n = 15). The study has revealed the interrelation of NETosis and rheumatoid factor in patients with RA and SLE, as well as NET formation and number of platelets in patients with GW.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Caitlyn L. Holmes ◽  
Daeun Shim ◽  
John Kernien ◽  
Chad J. Johnson ◽  
Jeniel E. Nett ◽  
...  

In rheumatoid arthritis, an autoimmune inflammatory arthritis, citrullinated proteins are targeted by autoantibodies and thus thought to drive disease. Neutrophil extracellular traps (NETs) are a source of citrullinated proteins and are increased in rheumatoid arthritis and therefore also implicated in disease pathogenesis. However, not all NETs are citrullinated. One theory aiming to clarify the intersection of citrullination, NETs, and rheumatoid arthritis suggests that specific stimuli induce different types of NETs defined by citrullination status. However, most studies do not evaluate uncitrullinated NETs, only citrullinated or total NETs. Further, the requirement for peptidylarginine deiminase (PAD) 2 and 4, two important citrullinating enzymes in neutrophils and rheumatoid arthritis, in the formation of different NETs has not been clearly defined. To determine if specific stimulants induce citrullinated or uncitrullinated NETs and if those structures require PAD2 or PAD4, human and murine neutrophils, including from PAD4-/- and PAD2-/- mice, were stimulated in vitro and NETs imaged and quantified. In humans, phorbol myristate acetate (PMA), ionomycin, monosodium urate (MSU), and Candida albicans induced NETs with MSU and C. albicans inducing primarily citrullinated, PMA primarily uncitrullinated, and ionomycin a mix of NETs. Only ionomycin and C. albicans were strong inducers of NETs in mice with ionomycin-induced NETs mostly citrullinated and C. albicans-induced NETs a mix of citrullinated and uncitrullinated. Interestingly, no stimulus induced exclusively citrullinated or uncitrullinated NETs. Further, PAD4 was required for citrullinated NETs only, whereas PAD2 was not required for either NET in mice. Therefore, specific stimuli induce varying proportions of both citrullinated and uncitrullinated NETs with different requirements for PAD4. These findings highlight the complexity of NET formation and the need to further define the mechanisms by which different NETs form and their implications for autoimmune disease.


1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar

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.


1987 ◽  
Vol 52 (9) ◽  
pp. 2317-2325 ◽  
Author(s):  
Jan Hlaváček ◽  
Jan Pospíšek ◽  
Jiřina Slaninová ◽  
Walter Y. Chan ◽  
Victor J. Hruby

[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.


1997 ◽  
Vol 62 (11) ◽  
pp. 1804-1814 ◽  
Author(s):  
Marie Stiborová ◽  
Hana Hansíková

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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