P2X7 Receptor Blockade Protects Against Acrolein-Induced Bladder Damage: A Potential New Therapeutic Approach for the Treatment of Bladder Inflammatory Diseases

Inflammatory conditions of the urinary bladder have been shown to be associated with urothelial damage and loss of function. The purinergic P2X7 receptor has been implicated in several inflammatory conditions. The aim of this study was to investigate the role of the P2X7 receptor in acrolein-induced inflammatory damage using the porcine urinary bladder. For this purpose, an ex-vivo model of porcine urothelial damage induced by direct instillation of acrolein into the whole bladder lumen was used. To determine the role of the P2X7 receptor, the bladders were pre-incubated with a selective P2X7 receptor antagonist, A804598 (10 μM), for 1 h. The effects of the acrolein-induced urothelial damage on the bladder’s function were assessed by examining the bladder wall contractile response, structure changes, apoptosis, and oxidative stress in the bladder tissues. The acrolein treatment led to significant damage to the urothelium histology, tight junction expression, and contractile responses. Acrolein also induced apoptosis in the mucosa layer. All these acrolein-induced responses were attenuated by pre-treatment with the P2X7 receptor antagonist A804598. Acrolein also significantly induced DNA oxidation in the submucosal layer; however, the P2X7 receptor antagonism did not show any protective effect towards the acrolein-induced oxidative stress. These findings suggested that the P2X7 receptor is involved in the acrolein-induced damage to the urothelium; therefore, the P2X7 receptor antagonists may be a new therapeutic option for the treatment of bladder inflammation.

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Abstract 5858: Role of Oxygen Tension and Oxidative Stress in Human Saphenous Vein Remodeling

Circulation ◽

10.1161/circ.118.suppl_18.s_1017-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Binata Joddar ◽

Rashmeet K Reen ◽

Michael Firstenberg ◽

Keith J Gooch

Keyword(s):

Oxidative Stress ◽

Oxygen Tension ◽

Ex Vivo ◽

Neointimal Hyperplasia ◽

Fold Increase ◽

List Type ◽

Saphenous Veins ◽

Arterial Po2 ◽

And Oxidative Stress

Vessels cultured ex vivo maintain viability and vasoactivity for weeks and can remodel in response to mechanical cues. When cultured in the presence of 5% CO2/balance air veins develop neointimal hyperplasia (IH) while arteries do not suggesting that exposure to significant increases in pO2 levels might stimulate IH. Neointimal hyperplasia (IH) is a known mechanism by which saphenous veins have a decreased patency compared to arterial conduits when used for coronary artery bypass. We sought to explore the role of oxygen tension and oxidative stress in IH. Test the hypothesis that exposure of human saphenous veins (HSV) to arterial pO2 stimulates IH via ROS-mediated pathways. Almost 40 HSV remnants acquired following CABG were cultured ex vivo with arterial (~95mmHg) pO2 or venous (~40mmHg) pO2 for 14 days. All differences reported have a p<0.05 via Student’s t-test. Results: HSV cultured at arterial pO2 exhibited significant IH as evidenced by disruption of the IEL, invasion of cells from the media, and a 2.8-fold greater intimal area than fresh HSV, a 5.8-fold increase in cell proliferation compared to fresh HSV, increased ROS levels and oxidative stress as evidenced by 4-fold increase in 4-HNE level (a marker of oxidative stress), increased DHE staining (indicative of superoxide generation), and a progressive increase in total ROS levels with time as assessed by DCF fluorescence, and a 3-fold increase in phosphorylated p38-MAPK, which is implicated in SMC proliferation. In stark contrast vessels culture at arterial pO2, HSV cultured with venous pO2 did not develop increased IH and were indistinguishable from fresh vessels with respect to proliferation, markers of oxidative stress, and MAPK expression levels. Supplementing culture medium with antioxidants including Tiron or NAC blocked the pO2-induced changes. These data indicate that exposure to arterial pO2 increases cellular proliferation and stimulates IH, potentially via oxidative stress or ROS signaling and also suggest that exposure to elevated arterial pO2 might stimulate pathological remodeling of veins grafted into the arterial circulation. This research has received full or partial funding support from the American Heart Association, AHA Great Rivers Affiliate (Delaware, Kentucky, Ohio, Pennsylvania & West Virginia).

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PPARβ/δ Priming Enhances the Anti-Apoptotic and Therapeutic Properties of Mesenchymal Stromal Cells in Myocardial Ischemia-Reperfusion Injury

10.21203/rs.3.rs-1139048/v1 ◽

2021 ◽

Author(s):

Charlotte Sarre ◽

Rafael Contreras Lopez ◽

Nitirut Nerpernpisooth ◽

Christian Barrere ◽

Sarah Bahraoui ◽

...

Keyword(s):

Oxidative Stress ◽

Myocardial Infarction ◽

Mesenchymal Stromal Cells ◽

Stromal Cells ◽

Ex Vivo ◽

Phase Iii ◽

Therapeutic Properties ◽

Cardioprotective Effects

Abstract Background: Mesenchymal Stromal Cells (MSC) have been widely used for their therapeutic properties in many clinical applications including myocardial infarction. Despite promising preclinical results and evidences of safety and efficacy in phases I/ II, inconsistencies in phase III trials have been reported. In a previous study, we have shown using MSC derived from the bone marrow of PPARβ/δ (Peroxisome proliferator-activated receptors β/δ) knockout mice that the acute cardioprotective properties of MSC during the first hour of reperfusion are PPARβ/δ-dependent but not related to the anti-inflammatory effect of MSC. However, the role of the modulation of PPARβ/δ expression on MSC cardioprotective and anti-apoptotic properties has never been investigated. Objectives: The aim of this study was to investigate the role of PPARβ/δ modulation (inhibition or activation) in MSC therapeutic properties in vitro and ex vivo in an experimental model of myocardial infarction.Methods and results: Naïve MSC and MSC pharmacologically activated or inhibited for PPARβ/δ were challenged with H202. Through specific DNA fragmentation quantification and qRT-PCR experiments, we evidenced in vitro an increased resistance to oxidative stress in MSC pre-treated by the PPARβ/δ agonist GW0742 versus naïve MSC. In addition, PPARβ/δ-priming allowed to reveal the anti-apoptotic effect of MSC on co-cultured cardiomyocytes. When injected during reperfusion in an ex vivo heart model of myocardial infarction, PPARβ/δ-primed MSC at a dose of 3.75x105 MSC/heart provided the same cardioprotective efficiency than 7.5x105 naïve MSC, identified as the optimal dose in our model. These enhanced short-term cardioprotective effects were associated with an increase in both anti-apoptotic effects and the number of MSC detected in the left ventricular wall at 1 hour of reperfusion. By contrast, inhibition of PPARβ/δ before their administration in post-ischemic hearts during reperfusion decreased their cardioprotective effects. Conclusion: Altogether these results revealed that PPARβ/δ-primed MSC exhibit an increased resistance to oxidative stress and enhanced anti-apoptotic properties on cardiac cells in vitro. PPARβ/δ-priming appears as an innovative strategy to enhance the cardioprotective effects of MSC and to decrease the injected doses. These results could be of major interest to improve MSC efficacy for the cardioprotection of injured myocardium in AMI patients.

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Role of EGFR/ErbB2 and PI3K/AKT/e-NOS in Lycium barbarum polysaccharides Ameliorating Endothelial Dysfunction Induced by Oxidative Stress

The American Journal of Chinese Medicine ◽

10.1142/s0192415x19500782 ◽

2019 ◽

Vol 47 (07) ◽

pp. 1523-1539 ◽

Cited By ~ 2

Author(s):

Wenjuan Zhang ◽

Huifang Yang ◽

Lingqin Zhu ◽

Yan Luo ◽

Lihong Nie ◽

...

Keyword(s):

Oxidative Stress ◽

Endothelial Dysfunction ◽

Cell Viability ◽

Therapeutic Option ◽

Critical Role ◽

Ang Ii ◽

Lycium Barbarum ◽

Underlying Mechanisms ◽

Lycium Barbarum Polysaccharides

Lycium barbarum polysaccharides (LBP) are the major ingredients of wolfberry. In this study, we investigated the role of LBP in endothelial dysfunction induced by oxidative stress and the underlying mechanisms using thoracic aortic endothelial cells of rat (RAECs) as a model. We found that Ang II inhibits cell viability of RAECs with 10[Formula: see text][Formula: see text]mol/L of Ang II treatment for 24[Formula: see text]h most potential ([Formula: see text]), the level of reactive oxygen species (ROS) is increased by Ang II treatment ([Formula: see text]), and the expression of Occludin and Zonula occludens-1 (ZO-1) is decreased by Ang II treatment ([Formula: see text]). However, preincubation of cells with LBP could inhibit the changes caused by Ang II, LBP increased cell viability ([Formula: see text]), decreased the level of ROS ([Formula: see text]), and up-regulated the expression of Occludin ([Formula: see text]) and ZO-1. In addition, Ang II treatment increased the expression of EGFR and p-EGFR (Try1172) and which can be inhibited by LBP. On the contrary, expression of ErbB2, p-ErbB2 (Try1248), PI3K, p-e-NOS (Ser1177) ([Formula: see text]), and p-AKT (Ser473) ([Formula: see text]) was inhibited by Ang II treatment and which can be increased by LBP. Treatment of the cells with inhibitors showed that the regulation of p-e-NOS and p-AKT expression by Ang II and LBP can be blocked by PI3K inhibitor wortmannin but not EGFR and ErbB2 inhibitor AC480. Taken together, our results suggested that LBP plays a critical role in maintaining the integrality of blood vessel endothelium through reduced production of ROS via regulating the activity of EGFR, ErbB2, PI3K/AKT/e-NOS, and which may offer a novel therapeutic option in the management of endothelial dysfunction.

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Antioxidants in Female Reproductive Biology

10.5772/intechopen.95937 ◽

2021 ◽

Author(s):

Banashree Nath ◽

Hirok Roy

Keyword(s):

Oxidative Stress ◽

Reproductive Biology ◽

Female Reproductive System ◽

Reproductive Disorders ◽

Oxidative Stress Biomarkers ◽

Inflammatory Conditions ◽

Ovarian Cancers ◽

Pathologic Processes ◽

Robust Evidence

Human female reproductive biology is a complex system and its pathologies are varied. However, majority of the pathologic processes involves the role of reactive oxygen species (ROS). Imbalance between the ROS and antioxidants results in oxidative stress (OS). OS is the pathognomonic factor in various female reproductive system ailments. OS contributes to the pathophysiology of infertility, pregnancy related complications, endometriosis, ovarian cancers, etc. Evidence of elevated oxidative stress biomarkers can be found in various inflammatory conditions. Numerous strategies have been postulated for management of OS related pathologic conditions. Antioxidants supplementation may play a crucial in prevention and management of these conditions. However, robust evidence is needed to support the role of antioxidants supplementation in various female reproductive disorders.

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Pancreas-Specific ARID1A Deficiency Promotes Acinar-to-Ductal Metaplasia and Elevates Interleukin-6 Expression in Experimental Pancreatitis Model

10.21203/rs.3.rs-326796/v1 ◽

2021 ◽

Author(s):

Liming Zhang ◽

Zhaoyun Li ◽

Yong Zhou ◽

Jie Zhu ◽

Chong Jin ◽

...

Keyword(s):

Acute Pancreatitis ◽

Epigenetic Regulation ◽

Interleukin 6 ◽

Ex Vivo ◽

Acinar Cells ◽

Genetically Engineered ◽

Ductal Cells ◽

Inflammatory Conditions ◽

Acinar To Ductal Metaplasia

Abstract Background: Although role of ARID1A in pancreatic homeostasis and tumorigenesis has been recently described using genetically engineered mouse (GEM) models, whether ARID1A plays a role in pancreatic inflammation and regeneration remains to be explored.Methods: Pancreas-specific Arid1a-deficient GEM model (Arid1adef) was generated by Ela1-Cre/ERT2 mice crossing with Arid1afl/fl mice and characterized histologically. In physiological and inflammatory conditions, serum amylase and lipase activity were measured to investigate effects of Arid1a deficiency on pancreatic secretion function. Histology analysis of pancreas was used to evaluate pancreatic lesions and recovery. Ex vivo primary acinar cell culture was employed to study acinar-to-ductal metaplasia (ADM) process. In HPNE cells, ARID1A knockdown and histone acetyltransferases inhibitors were used to explore epigenetic regulation on interleukin-6 (IL6) expression. Chromatin immunoprecipitation (ChIP) and quantitative real-time PCR were performed to analyze on IL6 promoters.Results: Arid1a deficiency promoted formation of ductal cysts characterized as silenced acinar genes and activated duct genes. Arid1a-deficient acinar cells were more inclined to trans-differentiation to ductal cells in cerulein-induced acute pancreatitis (AP) model. Expression analysis of proinflammatory cytokines reveals that ARID1A deficiency led to increased IL-6 expression in mice acinar cells and HPNE cells. ARID1A-associated histone acetylation partially involved in epigenetic regulation of IL-6. Conclusion: These results demonstrate ARID1A is involved in cerulein-induced AP development by mediating pro-inflammatory cytokines IL-6 and suggest that ARID1A-containing SWI/SNF complex is an epigenetic regulator of acute pancreatitis.

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Squalene: More than a Step toward Sterols

Antioxidants ◽

10.3390/antiox9080688 ◽

2020 ◽

Vol 9 (8) ◽

pp. 688 ◽

Cited By ~ 1

Author(s):

Marco Micera ◽

Alfonso Botto ◽

Federica Geddo ◽

Susanna Antoniotti ◽

Cinzia Margherita Bertea ◽

...

Keyword(s):

Oxidative Stress ◽

Free Radicals ◽

Cardiovascular Diseases ◽

Defense Mechanisms ◽

Current Knowledge ◽

Ex Vivo ◽

Antioxidant Properties ◽

Metabolic Intermediate ◽

Cellular Models

Squalene (SQ) is a natural triterpene widely distributed in nature. It is a metabolic intermediate of the sterol biosynthetic pathway and represents a possible target in different metabolic and oxidative stress-related disorders. Growing interest has been focused on SQ’s antioxidant properties, derived from its chemical structure. Strong evidence provided by ex vivo models underline its scavenging activity towards free radicals, whereas only a few studies have highlighted its effect in cellular models of oxidative stress. Given the role of unbalanced free radicals in both the onset and progression of several cardiovascular diseases, an in depth evaluation of SQ’s contribution to antioxidant defense mechanisms could represent a strategic approach in dealing with these pathological conditions. At present experimental results overall show a double-edged sword role of squalene in cardiovascular diseases and its function has to be better elucidated in order to establish intervention lines focused on its features. This review aims to summarize current knowledge about endogenous and exogenous sources of SQ and to point out the controversial role of SQ in cardiovascular physiology.

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Zebrafish Kit ligands cooperate with erythropoietin to promote erythroid cell expansion

Blood Advances ◽

10.1182/bloodadvances.2020001700 ◽

2020 ◽

Vol 4 (23) ◽

pp. 5915-5924

Author(s):

Jana Oltova ◽

Ondrej Svoboda ◽

Olga Machonova ◽

Petra Svatonova ◽

David Traver ◽

...

Keyword(s):

Suspension Culture ◽

Cell Expansion ◽

Ex Vivo ◽

Culture Conditions ◽

Erythroid Cell ◽

Loss Of Function ◽

Erythroid Progenitors ◽

Evolutionarily Conserved

Abstract Kit ligand (Kitlg) is pleiotropic cytokine with a prominent role in vertebrate erythropoiesis. Although the role of Kitlg in this process has not been reported in Danio rerio (zebrafish), in the present study we show that its function is evolutionarily conserved. Zebrafish possess 2 copies of Kitlg genes (Kitlga and Kitlgb) as a result of whole-genome duplication. To determine the role of each ligand in zebrafish, we performed a series of ex vivo and in vivo gain- and loss-of-function experiments. First, we tested the biological activity of recombinant Kitlg proteins in suspension culture from zebrafish whole-kidney marrow, and we demonstrate that Kitlga is necessary for expansion of erythroid progenitors ex vivo. To further address the role of kitlga and kitlgb in hematopoietic development in vivo, we performed gain-of-function experiments in zebrafish embryos, showing that both ligands cooperate with erythropoietin (Epo) to promote erythroid cell expansion. Finally, using the kita mutant (kitab5/b5 or sparse), we show that the Kita receptor is crucial for Kitlga/b cooperation with Epo in erythroid cells. In summary, using optimized suspension culture conditions with recombinant cytokines (Epo, Kitlga), we report, for the first time, ex vivo suspension cultures of zebrafish hematopoietic progenitor cells that can serve as an indispensable tool to study normal and aberrant hematopoiesis in zebrafish. Furthermore, we conclude that, although partial functional diversification of Kit ligands has been described in other processes, in erythroid development, both paralogs play a similar role, and their function is evolutionarily conserved.

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