A high magnesium concentration in citrate dialysate prevents oxidative stress and damage in human monocytes in vitro

Abstract Background The use of dialysis fluids (DFs) during haemodialysis has been associated with increased oxidative stress and reduced serum magnesium (Mg) levels, contributing to chronic inflammation. Since the role of Mg in modulating immune function and reducing oxidative stress has been demonstrated, the aim of this study was to characterize in vitro whether increasing the Mg concentration in DFs could protect immune cells from oxidative stress and damage. Methods The effect of citrate [citrate dialysis fluid (CDF), 1 mM] or acetate [acetate dialysis fluid (ADF), 3 mM] dialysates with low (0.5 mM; routinely used) or high (1 mM, 1.25 mM and 2 mM) Mg concentrations was assessed in THP-1 human monocytes. The levels of reactive oxygen species (ROS), malondialdehyde (MDA) and oxidized/reduced (GSSG/GSH) glutathione were quantified under basal and inflammatory conditions (stimulation with lipopolysaccharide, LPS). Results The increase of Mg in CDF resulted in a significant reduction of ROS production under basal and inflammatory conditions (extremely marked in 2 mM Mg; P < 0.001). These effects were not observed in ADF. Interestingly, in a dose-dependent manner, high Mg doses in CDF reduced oxidative stress in monocytes under both basal and inflammatory conditions. In fact, 2 mM Mg significantly decreased the levels of GSH, GSSG and MDA and the GSSG/GSH ratio in relation to 0.5 mM Mg. Conclusions CDF produces lower oxidative stress than ADF. The increase of Mg content in DFs, especially in CDF, could have a positive and protective effect in reducing oxidative stress and damage in immune cells, especially under inflammatory conditions.

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Increasing the Magnesium Concentration in Various Dialysate Solutions Differentially Modulates Oxidative Stress in a Human Monocyte Cell Line

Antioxidants ◽

10.3390/antiox9040319 ◽

2020 ◽

Vol 9 (4) ◽

pp. 319 ◽

Cited By ~ 1

Author(s):

Carmen Vida ◽

Julia Carracedo ◽

Patricia de Sequera ◽

Guillermo Bodega ◽

Rafael Pérez ◽

...

Keyword(s):

Oxidative Stress ◽

Human Monocyte ◽

Magnesium Concentration ◽

Ros Production ◽

Mda Content ◽

Monocyte Cell ◽

Vitro Effect ◽

Mg Content ◽

Dialysis Fluids

Oxidative stress is exacerbated in hemodialysis patients by several factors, including the uremic environment and the use of dialysis fluids (DFs). Since magnesium (Mg) plays a key role in modulating immune function and in reducing oxidative stress, we aimed to evaluate whether increasing the Mg concentration in different DFs could protect against oxidative stress in immunocompetent cells in vitro. Effect of ADF (acetate 3 mM), CDF (citrate 1 mM), and ACDF (citrate 0.8 mM + acetate 0.3 mM) dialysates with Mg at standard (0.5 mM) or higher (1, 1.25, and 2 mM) concentrations were assessed in THP-1 monocyte cultures. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were quantified under basal and uremic conditions (indoxyl sulfate (IS) treatment). Under uremic conditions, the three DFs with 0.5 mM Mg promoted higher ROS production and lipid damage than the control solution. However, CDF and ACDF induced lower levels of ROS and MDA, compared to that induced by ADF. High Mg concentration (1.25 and/or 2 mM) in CDF and ACDF protected against oxidative stress, indicated by reduced ROS and MDA levels compared to respective DFs with standard concentration of Mg. Increasing Mg concentrations in ADF promoted high ROS production and MDA content. Thus, an increase in Mg content in DFs has differential effects on the oxidative stress in IS-treated THP-1 cells depending on the dialysate used.

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VIP Inhibits Porphyromonas gingivalis LPS-induced Immune Responses in Human Monocytes

Journal of Dental Research ◽

10.1177/154405910508401106 ◽

2005 ◽

Vol 84 (11) ◽

pp. 999-1004 ◽

Cited By ~ 25

Author(s):

N. Foster ◽

J. Cheetham ◽

J.J. Taylor ◽

P.M. Preshaw

Keyword(s):

Immune Responses ◽

Porphyromonas Gingivalis ◽

Immune Cells ◽

Nuclear Translocation ◽

Dependent Manner ◽

Human Monocytes ◽

Tnf Α ◽

Autoimmune Conditions ◽

Porphyromonas Gingivalis Lps

Lipopolysaccharide (LPS) from the Gram-negative pathogen Porphyromonas gingivalis ( Pg) stimulates cytokine secretion in immune cells, and thereby initiates the inflammation associated with periodontitis. Modulation of pro-inflammatory cytokine activity is a plausible therapeutic target in periodontal disease. Vasoactive intestinal peptide (VIP) has a role in immunoregulation, and has been identified as a molecule with therapeutically beneficial immunosuppressive effects in inflammatory and autoimmune conditions. We aimed to investigate the effect of VIP on immune responses induced by Pg LPS in vitro. VIP (10−8 M) significantly (P < 0.05) inhibits TNF-α production by human monocytic THP1 cells stimulated with Pg LPS. In parallel, we showed that VIP inhibits nuclear translocation of NFκB and c-Jun in a time-dependent manner, but does not decrease the expression of CD14 receptors. This is the first report to show the potential of VIP as an immunomodulator of Pg-stimulated inflammatory pathways in human monocytes.

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Abstract P014: Oxidative Stress Mediated Regulation of Antioxidants in Cardiac Progenitor Cells

Circulation Research ◽

10.1161/res.109.suppl_1.ap014 ◽

2011 ◽

Vol 109 (suppl_1) ◽

Author(s):

Gokulakrishnan Iyer ◽

Michael E Davis

Keyword(s):

Oxidative Stress ◽

Xanthine Oxidase ◽

Progenitor Cells ◽

Cardiac Progenitor Cells ◽

Dependent Manner ◽

Akt Inhibitor ◽

Differentiation Potential ◽

Lineage Differentiation ◽

Phosphorylated Akt

Cardiac diseases are the leading causes of death throughout the world and transplantation of endogenous myocardial progenitor population with robust cardiovascular lineage differentiation potential is a promising therapeutic strategy. Therefore, in vitro expansion and transplantation of cardiac progenitor cells (CPCs) is currently in early clinical testing as a potential treatment for severe cardiac dysfunction. However, poor survival and engraftment of cells is one of the major limitations of cell transplantation therapy. Oxidative stress is increased in the ischemic myocardium and indirect inferences suggest the vulnerability of CPCs to oxidative stress. In this study, we show that in vitro, resident c-kit positive CPCs isolated from rat myocardium are significantly (p<0.05) resistant to superoxide-induced apoptosis compared to cardiomyocytes as analyzed by the number of sub-G1 population following xanthine/xanthine oxidase treatment. Interestingly, CPCs have two to four fold higher basal SOD1 and SOD2 activities (p<0.01) compared to cardiomyocytes and endothelial cells. Superoxide treatment increased expression of SOD1 (p<0.01), SOD2 (p<0.01), and glutathione peroxidase (p<0.05) mRNAs within 6 h of treatment compared to control cells. Recent studies suggest the involvement of AKT in controlling cell death, survival and also expression of SOD enzymes. Therefore, we investigated the involvement of AKT in CPCs subjected to oxidative stress. Western blot analysis revealed that the amount of phosphorylated AKT increased significantly within 10 minutes of xanthine/xanthine oxidase treatment. In addition, treatment with LY294002 - a PI3 kinase/AKT inhibitor, increased apoptosis in CPCs treated with superoxide. Our studies demonstrate a novel finding in which resident progenitor cells are protected from oxidative injury by containing higher basal levels of antioxidants as compared to myocytes. Moreover, under oxidant challenge antioxidant levels are regulated, possibly in an AKT-dependent manner. Further elucidation of this pathway may lead to novel therapeutic opportunities.

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

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/4235695 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 7

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.

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Human Proximal Tubule Epithelial Cells (HK-2) as a Sensitive In Vitro System for Ochratoxin A Induced Oxidative Stress

Toxins ◽

10.3390/toxins13110787 ◽

2021 ◽

Vol 13 (11) ◽

pp. 787

Author(s):

Enrique García-Pérez ◽

Dojin Ryu ◽

Hwa-Young Kim ◽

Hae Dun Kim ◽

Hyun Jung Lee

Keyword(s):

Oxidative Stress ◽

Ochratoxin A ◽

Cell Lines ◽

Time Dependent ◽

Mrna Levels ◽

Dependent Manner ◽

In Vitro System ◽

Glutathione Peroxidase 1 ◽

Glucose 6 Phosphate Dehydrogenase

Ochratoxin A (OTA) is a mycotoxin that is potentially carcinogenic to humans. Although its mechanism remains unclear, oxidative stress has been recognized as a plausible cause for the potent renal carcinogenicity observed in experimental animals. The effect of OTA on oxidative stress parameters in two cell lines of LLC-PK1 and HK-2 derived from the kidneys of pig and human, respectively, were investigated and compared. We found that the cytotoxicity of OTA on LLC-PK1 and HK-2 cells was dose- and time-dependent in both cell lines. Furthermore, increased intracellular reactive oxygen species (ROS) induced by OTA in both cell lines were observed in a time-dependent manner. Glutathione (GSH) was depleted by OTA at >48 h in HK-2 but not in LLC-PK1 cells. While the mRNA levels of glucose-6-phosphate dehydrogenase (G6PD) and glutathione peroxidase 1 (GPX1) in LLC-PK1 were down-regulated by 0.67- and 0.66-fold, respectively, those of catalase (CAT), glutathione reductase (GSR), and superoxide dismutase 1 (SOD) in HK-2 were up-regulated by 2.20-, 2.24-, and 2.75-fold, respectively, after 72 h exposure to OTA. Based on these results, we conclude that HK-2 cells are more sensitive to OTA-mediated toxicity than LLC-PK1, and OTA can cause a significant oxidative stress in HK-2 as indicated by changes in the parameter evaluated.

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Hyperglycemic Memory of Innate Immune Cells Promotes In Vitro Proinflammatory Responses of Human Monocytes and Murine Macrophages

The Journal of Immunology ◽

10.4049/jimmunol.1901348 ◽

2021 ◽

pp. ji1901348

Author(s):

Kathrin Thiem ◽

Samuel T. Keating ◽

Mihai G. Netea ◽

Niels P. Riksen ◽

Cees J. Tack ◽

...

Keyword(s):

Immune Cells ◽

Innate Immune ◽

Innate Immune Cells ◽

Human Monocytes ◽

Murine Macrophages ◽

Proinflammatory Responses

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INTEGRINS MEDIATE PLACENTAL EXTRACELLULAR VESICLE TRAFFICKING TO LUNG AND LIVER IN VIVO

10.1101/2020.09.22.309047 ◽

2020 ◽

Author(s):

Sean L. Nguyen ◽

Soo Hyun Ahn ◽

Jacob W. Greenberg ◽

Benjamin W. Collaer ◽

Dalen W. Agnew ◽

...

Keyword(s):

Immune Cells ◽

Extracellular Vesicle ◽

Dependent Manner ◽

Cellular Phenotype ◽

Reporter Mouse ◽

Membrane Bound ◽

First Time

ABSTRACTMembrane-bound extracellular vesicles (EVs) mediate intercellular communication in all organisms, and those produced by placental mammals have become increasingly recognized as significant mediators of fetal-maternal communication. Here, we aimed to identify maternal cells targeted by placental EVs and elucidate the mechanisms by which they traffic to these cells. Exogenously administered pregnancy-associated EVs traffic specifically to the lung; further, placental EVs associate with lung interstitial macrophages and liver Kupffer cells in an integrin-dependent manner. Localization of EV to maternal lungs was confirmed in unmanipulated pregnancy using a transgenic reporter mouse model, which also provided in situ and in vitro evidence that fetally-derived EVs, rarely, may cause genetic alteration of maternal cells. These results provide for the first time direct in vivo evidence for targeting of placental EVs to maternal immune cells, and further, evidence that EVs can alter cellular phenotype.

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p-Coumaric Acid Protects Human Lens Epithelial Cells against Oxidative Stress-Induced Apoptosis by MAPK Signaling

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/8549052 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 13

Author(s):

Jiao Peng ◽

Ting-ting Zheng ◽

Yue Liang ◽

Li-fang Duan ◽

Yao-dong Zhang ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Mapk Signaling ◽

Human Lens ◽

Lens Epithelial Cells ◽

Dependent Manner ◽

Coumaric Acid ◽

Underlying Mechanisms ◽

Induced Apoptosis

To protect against oxidative stress-induced apoptosis in lens epithelial cells is a potential strategy in preventing cataract formation. The present study aimed at studying the protective effect and underlying mechanisms of p-coumaric acid (p-CA) on hydrogen peroxide- (H2O2-) induced apoptosis in human lens epithelial (HLE) cells (SRA 01–04). Cells were pretreated with p-CA at a concentration of 3, 10, and 30 μM before the treatment of H2O2 (275 μM). Results showed that pretreatment with p-CA significantly protected against H2O2-induced cell death in a dose-dependent manner, as well as downregulating the expressions of both cleaved caspase-3 and cleaved caspase-9 in HLE cells. Moreover, p-CA also greatly suppressed H2O2-induced intracellular ROS production and mitochondrial membrane potential loss and elevated the activities of T-SOD, CAT, and GSH-Px of H2O2-treated cells. As well, in vitro study showed that p-CA also suppressed H2O2-induced phosphorylation of p-38, ERK, and JNK in HLE cells. These findings demonstrate that p-CA suppresses H2O2-induced HLE cell apoptosis through modulating MAPK signaling pathways and suggest that p-CA has a potential therapeutic role in the prevention of cataract.

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Ganoderic Acid D Protects Human Amniotic Mesenchymal Stem Cells against Oxidative Stress-Induced Senescence through the PERK/NRF2 Signaling Pathway

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/8291413 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Yan Xu ◽

Huan Yuan ◽

Yi Luo ◽

Yu-Jie Zhao ◽

Jian-Hui Xiao

Keyword(s):

Oxidative Stress ◽

Stem Cells ◽

Signaling Pathway ◽

Adult Stem Cells ◽

Telomerase Activity ◽

Related Factor ◽

Dependent Manner ◽

Ganoderic Acid ◽

Nrf2 Signaling Pathway

Aging is an important risk factor in the occurrence of many chronic diseases. Senescence and exhaustion of adult stem cells are considered as a hallmark of aging in organisms. In this study, a senescent human amniotic mesenchymal stem cell (hAMSC) model subjected to oxidative stress was established in vitro using hydrogen peroxide. We investigated the effects of ganoderic acid D (GA-D), a natural triterpenoid compound produced from Ganoderma lucidum, on hAMSC senescence. GA-D significantly inhibited β-galactosidase (a senescence-associated marker) formation, in a dose-dependent manner, with doses ranging from 0.1 μM to 10 μM, without inducing cytotoxic side-effects. Furthermore, GA-D markedly inhibited the generation of reactive oxygen species (ROS) and the expression of p21 and p16 proteins, relieved the cell cycle arrest, and enhanced telomerase activity in senescent hAMSCs. Furthermore, GA-D upregulated the expression of phosphorylated protein kinase R- (PKR-) like endoplasmic reticulum kinase (PERK), peroxidase III (PRDX3), and nuclear factor-erythroid 2-related factor (NRF2) and promoted intranuclear transfer of NRF2 in senescent cells. The PERK inhibitor GSK2656157 and/or the NRF2 inhibitor ML385 suppressed the PERK/NRF2 signaling, which was activated by GA-D. They induced a rebound for the generation of ROS and β-galactosidase-positive cells and attenuated the differentiation capacity. These findings suggest that GA-D retards hAMSC senescence through activation of the PERK/NRF2 signaling pathway and may be a promising candidate for the discovery of antiaging agents.

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Encircling granulosa cells protects against di-(2-ethylhexyl)phthalate-induced apoptosis in rat oocytes cultured in vitro

Zygote ◽

10.1017/s0967199419000121 ◽

2019 ◽

Vol 27 (4) ◽

pp. 203-213 ◽

Cited By ~ 1

Author(s):

Anima Tripathi ◽

Vivek Pandey ◽

A.N. Sahu ◽

Alok K. Singh ◽

Pawan K. Dubey

Keyword(s):

Oxidative Stress ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Granulosa Cells ◽

Mitochondrial Membrane ◽

Dependent Manner ◽

Apoptotic Markers ◽

Induced Apoptosis ◽

Ethylhexyl Phthalate

SummaryThe present study investigated if the presence of encircling granulosa cells protected against di(2-ethylhexyl)phthalate (DEHP)-induced oxidative stress in rat oocytes cultured in vitro. Denuded oocytes and cumulus–oocyte complexes (COCs) were treated with or without various doses of DEHP (0.0, 25.0, 50.0, 100, 200, 400 and 800 μM) in vitro. Morphological apoptotic changes, levels of oxidative stress and reactive oxygen species (ROS), mitochondrial membrane potential, and expression levels of apoptotic markers (Bcl2, Bax, cytochrome c) were analyzed. Our results showed that DEHP induced morphological apoptotic changes in a dose-dependent manner in denuded oocytes cultured in vitro. The effective dose of DEHP (400 µg) significantly (P>0.05) increased oxidative stress by elevating ROS levels and the mitochondrial membrane potential with higher mRNA expression and protein levels of apoptotic markers (Bax, cytochrome c). Encircling granulosa cells protected oocytes from DEHP-induced morphological changes, increased oxidative stress and ROS levels, as well as increased expression of apoptotic markers. Taken together our data suggested that encircling granulosa cells protected oocytes against DEHP-induced apoptosis and that the presence of granulosa cells could act positively towards the survival of oocytes under in vitro culture conditions and may be helpful during assisted reproductive technique programmes.

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