Research

20 pages, 3903 KiB

Open AccessArticle

Hydrogen Peroxide Promotes the Production of Radiation-Derived EVs Containing Mitochondrial Proteins

by Caitlin E. Miller, Fangfang Xu, Yanming Zhao, Wei Luo, Weixiong Zhong, Kristy Meyer, Rani Jayswal, Heidi L. Weiss, William H. St. Clair, Daret K. St. Clair and Luksana Chaiswing

Antioxidants 2022, 11(11), 2119; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox11112119 - 27 Oct 2022

Cited by 4 | Viewed by 1930

Abstract

In spite of extensive successes, cancer recurrence after radiation treatment (RT) remains one of the significant challenges in the cure of localized prostate cancer (PCa). This study focuses on elucidating a novel adaptive response to RT that could contribute to cancer recurrence. Here, [...] Read more.

In spite of extensive successes, cancer recurrence after radiation treatment (RT) remains one of the significant challenges in the cure of localized prostate cancer (PCa). This study focuses on elucidating a novel adaptive response to RT that could contribute to cancer recurrence. Here, we used PC3 cell line, an adenocarcinoma from a bone metastasis and radio-resistant clone 695 cell line, which survived after total radiation dose of 66 Gy (2 Gy × 33) and subsequently regrew in nude mice after exposure to fractionated radiation at 10 Gy (2 Gy × 5). Clone 695 cells not only showed an increase in surviving fraction post-radiation but also an increase in hydrogen peroxide (H₂O₂) production when compared to PC3 cells. At the single cell level, confocal microscope images coupled with IMARIS rendering software demonstrate an increase in mitochondrial mass and membrane potential in clone 695 cells. Utilizing the Seahorse XF96 instrument to investigate mitochondrial respiration, clone 695 cells demonstrated a higher basal Oxygen Consumption Rate (OCR), ATP-linked OCR, and proton leak compared to PC3 cells. The elevation of mitochondrial function in clone 695 cells is accompanied by an increase in mitochondrial H₂O₂ production. These data suggest that H₂O₂ could reprogram PCa’s mitochondrial homeostasis, which allows the cancer to survive and regrow after RT. Upon exposure to RT, in addition to ROS production, we found that RT induces the release of extracellular vesicles (EVs) from PC3 cells (p < 0.05). Importantly, adding H₂O₂ to PC3 cells promotes EVs production in a dose-dependent manner and pre-treatment with polyethylene glycol-Catalase mitigates H₂O₂-mediated EV production. Both RT-derived EVs and H₂O₂-derived EVs carried higher levels of mitochondrial antioxidant proteins including, Peroxiredoxin 3, Glutathione Peroxidase 4 as well as mitochondrial-associated oxidative phosphorylation proteins. Significantly, adding isolated functional mitochondria 24 h prior to RT shows a significant increase in surviving fractions of PC3 cells (p < 0.05). Together, our findings reveal that H₂O₂ promotes the production of EVs carrying mitochondrial proteins and that functional mitochondria enhance cancer survival after RT. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

17 pages, 4719 KiB

Open AccessArticle

Characterization of H₂O₂-Induced Alterations in Global Transcription of mRNA and lncRNA

by Shihua Liu, Ya Qiu, Rong Xiang and Peng Huang

Antioxidants 2022, 11(3), 495; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox11030495 - 03 Mar 2022

Cited by 2 | Viewed by 2367

Abstract

Hydrogen peroxide (H₂O₂) is an important reactive oxygen species that plays a major role in redox signaling. Although H₂O₂ is known to regulate gene expression and affect multiple cellular processes, the characteristics and mechanisms of such [...] Read more.

Hydrogen peroxide (H₂O₂) is an important reactive oxygen species that plays a major role in redox signaling. Although H₂O₂ is known to regulate gene expression and affect multiple cellular processes, the characteristics and mechanisms of such transcriptional regulation remain to be defined. In this study, we utilized transcriptome sequencing to determine the global changes of mRNA and lncRNA transcripts induced by H₂O₂ in human pancreatic normal epithelial (HPNE) and pancreatic cancer (PANC-1) cells. Promoter analysis using PROMO and TRRUST revealed that mRNAs and lncRNAs largely shared the same sets of transcription factors in response to ROS stress. Interestingly, promoters of the upregulated genes were similar to those of the downregulated transcripts, suggesting that the H₂O₂-responding promoters are conserved but they alone do not determine the levels of transcriptional outputs. We also found that H₂O₂ induced significant changes in molecules involved in the pathways of RNA metabolism, processing, and transport. Detailed analyses further revealed a significant difference between pancreatic cancer and noncancer cells in their response to H₂O₂ stress, especially in the transcription of genes involved in cell-cycle regulation and DNA repair. Our study provides new insights into RNA transcriptional regulation upon ROS stress in cancer and normal cells. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

34 pages, 4808 KiB

Open AccessArticle

Inhibition of Membrane-Associated Catalase, Extracellular ROS/RNS Signaling and Aquaporin/H₂O₂-Mediated Intracellular Glutathione Depletion Cooperate during Apoptosis Induction in the Human Gastric Carcinoma Cell Line MKN-45

by Georg Bauer

Antioxidants 2021, 10(10), 1585; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10101585 - 09 Oct 2021

Cited by 5 | Viewed by 2094

Abstract

The human gastric carcinoma cell line MKN-45 is a prototype of bona fide tumor cells, as it is protected from the NADPH oxidase-1 (NOX-1)-driven HOCl- and nitric oxide (NO)/peroxynitrite apoptosis-inducing signaling pathways by a membrane-associated catalase. The use of inhibitors/scavengers shows that inhibition [...] Read more.

The human gastric carcinoma cell line MKN-45 is a prototype of bona fide tumor cells, as it is protected from the NADPH oxidase-1 (NOX-1)-driven HOCl- and nitric oxide (NO)/peroxynitrite apoptosis-inducing signaling pathways by a membrane-associated catalase. The use of inhibitors/scavengers shows that inhibition of membrane-associated catalase is sufficient for the activation of NO/peroxynitrite or HOCl signaling. However, this signaling is not sufficient for apoptosis induction, as intracellular glutathione peroxidase/glutathione counteracts these signaling effects. Therefore, intrusion of extracellular tumor cell-derived H₂O₂ through aquaporins is required for the full apoptosis-inducing effect of extracellular reactive oxygen/nitrogen species. This secondary step in apoptosis induction can be prevented by inhibition of aquaporins, inhibition of NOX1 and decomposition of H₂O₂. Pretreatment with inhibitors of glutathione synthase or the cysteine-glutamine antiporter (xC transporter) abrogate the requirement for aquaporin/H₂O₂-mediated glutathione depletion, thus demonstrating that intracellular glutathione is the target of intruding H₂O₂. These data allow definition of mechanistic interactions between ROS/RNS signaling after inhibition of membrane-associated catalase, the sensitizing effects of aquaporins/H₂O₂ and the counteraction of the xC transporter/glutathione synthase system. Knowledge of these mechanistic interactions is required for the understanding of selective apoptosis induction in tumor cells through reestablishment of apoptosis-inducing ROS/RNS signaling. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Graphical abstract

21 pages, 5172 KiB

Open AccessArticle

Early Cytokine-Induced Transient NOX2 Activity Is ER Stress-Dependent and Impacts β-Cell Function and Survival

by Eloisa A. Vilas-Boas, Christopher Carlein, Lisa Nalbach, Davidson C. Almeida, Emmanuel Ampofo, Angelo R. Carpinelli, Leticia P. Roma and Fernanda Ortis

Antioxidants 2021, 10(8), 1305; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10081305 - 18 Aug 2021

Cited by 5 | Viewed by 2544

Abstract

In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J [...] Read more.

In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J wild-type (WT), NOX1 KO and NOX2 KO mice were exposed to a PIC combination. We show that cytokines increase O₂^•− production after 2 h in WT and NOX1 KO but not in NOX2 KO islets. Using transgenic mice constitutively expressing a genetically encoded compartment specific H₂O₂ sensor, we show, for the first time, a transient increase of cytosolic/nuclear H₂O₂ in islet cells between 4 and 5 h during cytokine exposure. The H₂O₂ increase coincides with the intracellular NAD(P)H decrease and is absent in NOX2 KO islets. NOX2 KO confers better glucose tolerance and protects against cytokine-induced islet secretory dysfunction and death. However, NOX2 absence does not counteract the cytokine effects in ER Ca²⁺ depletion, Store-Operated Calcium Entry (SOCE) increase and ER stress. Instead, the activation of ER stress precedes H₂O₂ production. As early NOX2-driven ROS production impacts β-cells’ function and survival during insulitis, NOX2 might be a potential target for designing therapies against early β-cell dysfunction in the context of T1D onset. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

12 pages, 1971 KiB

Open AccessArticle

SOD3 Is a Non-Mutagenic Growth Regulator Affecting Cell Migration and Proliferation Signal Transduction

by Alessia Parascandolo and Mikko O. Laukkanen

Antioxidants 2021, 10(5), 635; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10050635 - 21 Apr 2021

Cited by 5 | Viewed by 2118

Abstract

Superoxide dismutase (SOD) family isoenzymes, SOD1, SOD2, and SOD3, synthesize hydrogen peroxide (H₂O₂), which regulates the signal transduction. H₂O₂ is a second messenger able to enter into the cells through aquaporin 3 cell membrane channels and [...] Read more.

Superoxide dismutase (SOD) family isoenzymes, SOD1, SOD2, and SOD3, synthesize hydrogen peroxide (H₂O₂), which regulates the signal transduction. H₂O₂ is a second messenger able to enter into the cells through aquaporin 3 cell membrane channels and to modify protein tyrosine phosphatase activity. SOD3 has been shown to activate signaling pathways in tissue injuries, inflammation, and cancer models. Similar to the H₂O₂ response in the cells, the cellular response of SOD3 is dose-dependent; even a short supraphysiological concentration reduces the cell survival and activates the growth arrest and apoptotic signaling, whereas the physiological SOD3 levels support its growth and survival. In the current work, we studied the signaling networks stimulated by SOD3 overexpression demonstrating a high diversity in the activation of signaling cascades. The results obtained suggest that SOD3, although inducing cell growth and affecting various biological processes, does not cause detectable long-term DNA aberrations. Therefore, according to the present data, SOD3 is not a mutagen. Additionally, we compared SOD3-driven immortalized mouse embryonic fibroblasts to SV40 immortalized NIH3T3 cells, demonstrating a marked difference in the activation of cellular kinases. The data presented may contain important druggable targets to abrogate unwanted cell growth. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

14 pages, 2205 KiB

Open AccessArticle

Catalase Modulates the Radio-Sensitization of Pancreatic Cancer Cells by Pharmacological Ascorbate

by Juan Du, Rory S. Carroll, Garett J. Steers, Brett A. Wagner, Brianne R. O’Leary, Chris S. Jensen, Garry R. Buettner and Joseph J. Cullen

Antioxidants 2021, 10(4), 614; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10040614 - 16 Apr 2021

Cited by 4 | Viewed by 2522

Abstract

Pancreatic cancer cells (PDACs) are more susceptible to an oxidative insult than normal cells, resulting in greater cytotoxicity upon exposure to agents that increase pro-oxidant levels. Pharmacological ascorbate (P-AscH⁻), i.e., large amounts given intravenously (IV), generates significant fluxes of hydrogen peroxide [...] Read more.

Pancreatic cancer cells (PDACs) are more susceptible to an oxidative insult than normal cells, resulting in greater cytotoxicity upon exposure to agents that increase pro-oxidant levels. Pharmacological ascorbate (P-AscH⁻), i.e., large amounts given intravenously (IV), generates significant fluxes of hydrogen peroxide (H₂O₂), resulting in the killing of PDACs but not normal cells. Recent studies have demonstrated that P-AscH⁻ radio-sensitizes PDAC but is a radioprotector to normal cells and tissues. Several mechanisms have been hypothesized to explain the dual roles of P-AscH⁻ in radiation-induced toxicity including the activation of nuclear factor-erythroid 2-related factor 2 (Nrf2), RelB, as well as changes in bioenergetic profiles. We have found that P-AscH⁻ in conjunction with radiation increases Nrf2 in both cancer cells and normal cells. Although P-AscH⁻ with radiation decreases RelB in cancer cells vs. normal cells, the knockout of RelB does not radio-sensitize PDACs. Cellular bioenergetic profiles demonstrate that P-AscH⁻ with radiation increases the ATP demand/production rate (glycolytic and oxidative phosphorylation) in both PDACs and normal cells. Knocking out catalase results in P-AscH⁻ radio-sensitization in PDACs. In a phase I trial where P-AscH⁻ was included as an adjuvant to the standard of care, short-term survivors had higher catalase levels in tumor tissue, compared to long-term survivors. These data suggest that P-AscH⁻ radio-sensitizes PDACs through increased peroxide flux. Catalase levels could be a possible indicator for how tumors will respond to P-AscH⁻. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

Review

Jump to: Research, Other

12 pages, 793 KiB

Open AccessReview

Bad Smells and Broken DNA: A Tale of Sulfur-Nucleic Acid Cooperation

by Rodney E. Shackelford, Yan Li, Ghali E. Ghali and Christopher G. Kevil

Antioxidants 2021, 10(11), 1820; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10111820 - 17 Nov 2021

Cited by 3 | Viewed by 2576

Abstract

Hydrogen sulfide (H₂S) is a gasotransmitter that exerts numerous physiologic and pathophysiologic effects. Recently, a role for H₂S in DNA repair has been identified, where H₂S modulates cell cycle checkpoint responses, the DNA damage response (DDR), and [...] Read more.

Hydrogen sulfide (H₂S) is a gasotransmitter that exerts numerous physiologic and pathophysiologic effects. Recently, a role for H₂S in DNA repair has been identified, where H₂S modulates cell cycle checkpoint responses, the DNA damage response (DDR), and mitochondrial and nuclear genomic stability. In addition, several DNA repair proteins modulate cellular H₂S concentrations and cellular sulfur metabolism and, in turn, are regulated by cellular H₂S concentrations. Many DDR proteins are now pharmacologically inhibited in targeted cancer therapies. As H₂S and the enzymes that synthesize it are increased in many human malignancies, it is likely that H₂S synthesis inhibition by these therapies is an underappreciated aspect of these cancer treatments. Moreover, both H₂S and DDR protein activities in cancer and cardiovascular diseases are becoming increasingly apparent, implicating a DDR–H₂S signaling axis in these pathophysiologic processes. Taken together, H₂S and DNA repair likely play a central and presently poorly understood role in both normal cellular function and a wide array of human pathophysiologic processes. Here, we review the role of H₂S in DNA repair. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

Other

Jump to: Research, Review

12 pages, 971 KiB

Open AccessSystematic Review

The Uncoupling Proteins: A Systematic Review on the Mechanism Used in the Prevention of Oxidative Stress

by Jonathan Hirschenson, Emiliano Melgar-Bermudez and Ryan J. Mailloux

Antioxidants 2022, 11(2), 322; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox11020322 - 06 Feb 2022

Cited by 41 | Viewed by 3519

Abstract

Mitochondrial uncoupling proteins (UCP) 1-3 fulfill many physiological functions, ranging from non-shivering thermogenesis (UCP1) to glucose-stimulated insulin release (GSIS) and satiety signaling (UCP2) and muscle fuel metabolism (UCP3). Several studies have suggested that UCPs mediate these functions by facilitating proton return to the [...] Read more.

Mitochondrial uncoupling proteins (UCP) 1-3 fulfill many physiological functions, ranging from non-shivering thermogenesis (UCP1) to glucose-stimulated insulin release (GSIS) and satiety signaling (UCP2) and muscle fuel metabolism (UCP3). Several studies have suggested that UCPs mediate these functions by facilitating proton return to the matrix. This would decrease protonic backpressure on the respiratory chain, lowering the production of hydrogen peroxide (H₂O₂), a second messenger. However, controlling mitochondrial H₂O₂ production to prevent oxidative stress by activating these leaks through these proteins is still enthusiastically debated. This is due to compelling evidence that UCP2/3 fulfill other function(s) and the inability to reproduce findings that UCP1-3 use inducible leaks to control reactive oxygen species (ROS) production. Further, other studies have found that UCP2/3 may serve as Ca²⁺. Therefore, we performed a systematic review aiming to summarize the results collected on the topic. A literature search using a list of curated keywords in Pubmed, BIOSIS Citation Index and Scopus was conducted. Potentially relevant references were screened, duplicate references eliminated, and then literature titles and abstracts were evaluated using Rayyan software. A total of 1101 eligible studies were identified for the review. From this total, 416 studies were evaluated based on our inclusion criteria. In general, most studies identified a role for UCPs in preventing oxidative stress, and in some cases, this may be related to the induction of leaks and lowering protonic backpressure on the respiratory chain. However, some studies also generated evidence that UCP2/3 may mitigate oxidative stress by transporting Ca²⁺ into the matrix, exporting lipid hydroperoxides, or by transporting C-4 metabolites. Additionally, some showed that activating UCP1 or 3 can increase mitochondrial ROS production, even though there is still augmented protection from oxidative stress. Conclusion: Overall, most available studies demonstrate that UCPs, particularly UCP2/3, prevent oxidative stress. However, the mechanism utilized to do so remains elusive and raises the question that UCP2/3 should be renamed, since they may still not be true “uncoupling proteins”. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Hydrogen Peroxide in Redox Signaling

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (8 papers)

Research

Review

Other

Further Information

Guidelines

MDPI Initiatives

Follow MDPI