1
|
Goralski T, Ram JL. Extracellular Calcium Receptor as a Target for Glutathione and Its Derivatives. Int J Mol Sci 2022; 23:ijms23020717. [PMID: 35054903 PMCID: PMC8776003 DOI: 10.3390/ijms23020717] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/03/2022] [Accepted: 01/05/2022] [Indexed: 12/16/2022] Open
Abstract
Extracellular glutathione (GSH) and oxidized glutathione (GSSG) can modulate the function of the extracellular calcium sensing receptor (CaSR). The CaSR has a binding pocket in the extracellular domain of CaSR large enough to bind either GSH or GSSG, as well as the naturally occurring oxidized derivative L-cysteine glutathione disulfide (CySSG) and the compound cysteinyl glutathione (CysGSH). Modeling the binding energies (ΔG) of CySSG and CysGSH to CaSR reveals that both cysteine derivatives may have greater affinities for CaSR than either GSH or GSSG. GSH, CySSG, and GSSG are found in circulation in mammals and, among the three, CySSG is more affected by HIV/AIDs and aging than either GSH or GSSG. The beta-carbon linkage of cysteine in CysGSH may model a new class of calcimimetics, exemplified by etelcalcetide. Circulating glutathionergic compounds, particularly CySSG, may mediate calcium-regulatory responses via receptor-binding to CaSR in a variety of organs, including parathyroids, kidneys, and bones. Receptor-mediated actions of glutathionergics may thus complement their roles in redox regulation and detoxification. The glutathionergic binding site(s) on CaSR are suggested to be a target for development of drugs that can be used in treating kidney and other diseases whose mechanisms involve CaSR dysregulation.
Collapse
Affiliation(s)
- Thomas Goralski
- Department of Physiology, Wayne State University, Detroit, MI 48201, USA;
- Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Jeffrey L. Ram
- Department of Physiology, Wayne State University, Detroit, MI 48201, USA;
- Correspondence: ; Tel.: +1-248-200-9431
| |
Collapse
|
2
|
|
3
|
Azzam EI. What does radiation biology tell us about potential health effects at low dose and low dose rates? JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:S28-S39. [PMID: 31216522 DOI: 10.1088/1361-6498/ab2b09] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The health risks to humans exposed to low dose and low dose rate ionising radiation remain ambiguous and are the subject of debate. The need to establish risk assessment standards based on the mechanisms underlying low dose/low fluence radiation exposures has been recognised by scholarly and regulatory bodies as critical for reducing the uncertainty in predicting adverse health risks of human exposure to low doses of radiation. Here, a brief review of laboratory-based evidence of molecular and biochemical changes induced by low doses and low dose rates of radiation is presented. In particular, two phenomena, namely bystander effects and adaptive responses that may impact low-level radiation health risks, are discussed together with the need for further studies. The expansion of this knowledge by considering the important variables that affect the radiation response (e.g. genetic susceptibility, time after exposure), and using the latest advances in experimental models and bioinformatics tools, may guide epidemiological studies towards reducing the uncertainty in predicting the potential health hazards of exposure to low-dose radiation.
Collapse
Affiliation(s)
- Edouard I Azzam
- Departments of Radiology, RUTGERS New Jersey Medical School, Newark, NJ 07103, United States of America
| |
Collapse
|
4
|
Decrock E, Hoorelbeke D, Ramadan R, Delvaeye T, De Bock M, Wang N, Krysko DV, Baatout S, Bultynck G, Aerts A, Vinken M, Leybaert L. Calcium, oxidative stress and connexin channels, a harmonious orchestra directing the response to radiotherapy treatment? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1099-1120. [DOI: 10.1016/j.bbamcr.2017.02.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/02/2017] [Accepted: 02/04/2017] [Indexed: 02/07/2023]
|
5
|
Hu L, Wang H, Huang L, Zhao Y, Wang J. Crosstalk between autophagy and intracellular radiation response (Review). Int J Oncol 2016; 49:2217-2226. [PMID: 27748893 DOI: 10.3892/ijo.2016.3719] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 09/27/2016] [Indexed: 11/06/2022] Open
Abstract
Autophagy induced by radiation is critical to cell fate decision. Evidence now sheds light on the importance of autophagy induced by cancer radiotherapy. Traditional view considers radiation can directly or indirectly damage DNA which can activate DNA damage the repair signaling pathway, a large number of proteins participating in DNA damage repair signaling pathway such as p53, ATM, PARP1, FOXO3a, mTOR and SIRT1 involved in autophagy regulation. However, emerging recent evidence suggests radiation can also cause injury to extranuclear targets such as plasma membrane, mitochondria and endoplasmic reticulum (ER) and induce accumulation of ceramide, ROS, and Ca2+ concentration which activate many signaling pathways to modulate autophagy. Herein we review the role of autophagy in radiation therapy and the potent intracellular autophagic triggers induced by radiation. We aim to provide a more theoretical basis of radiation-induced autophagy, and provide novel targets for developing cytotoxic drugs to increase radiosensitivity.
Collapse
Affiliation(s)
- Lelin Hu
- Department of Radiation Oncology, Peking University Third Hospital, Haidian, Beijing 100191, P.R. China
| | - Hao Wang
- Department of Radiation Oncology, Peking University Third Hospital, Haidian, Beijing 100191, P.R. China
| | - Li Huang
- Department of Radiation Oncology, Peking University Third Hospital, Haidian, Beijing 100191, P.R. China
| | - Yong Zhao
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Junjie Wang
- Department of Radiation Oncology, Peking University Third Hospital, Haidian, Beijing 100191, P.R. China
| |
Collapse
|
6
|
Kataoka T. Study of antioxidative effects and anti-inflammatory effects in mice due to low-dose X-irradiation or radon inhalation. JOURNAL OF RADIATION RESEARCH 2013; 54:587-96. [PMID: 23420683 PMCID: PMC3709669 DOI: 10.1093/jrr/rrs141] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 12/20/2012] [Accepted: 12/24/2012] [Indexed: 05/30/2023]
Abstract
Low-dose irradiation induces various stimulating effects, especially activation of the biological defense system including antioxidative and immune functions. Oxidative stress induced by reactive oxygen species (ROS) can cause cell damage and death and can induce many types of diseases. This paper reviews new insights into inhibition of ROS-related diseases with low-dose irradiation or radon inhalation. X-irradiation (0.5 Gy) before or after carbon tetrachloride (CCl4) treatment inhibits hepatopathy in mice. X-irradiation (0.5 Gy) before ischemia-reperfusion injury or cold-induced brain injury also inhibits edema. These findings suggest that low-dose X-irradiation has antioxidative effects due to blocking the damage induced by free radicals or ROS. Moreover, radon inhalation increases superoxide dismutase activity in many organs and inhibits CCl4-induced hepatic and renal damage and streptozotocin-induced type I diabetes. These findings suggest that radon inhalation also has antioxidative effects. This antioxidative effect against CCl4-induced hepatopathy is comparable to treatment with ascorbic acid (vitamin C) at a dose of 500 mg/kg weight, or α-tocopherol (vitamin E) treatment at a dose of 300 mg/kg weight, and is due to activation of antioxidative functions. In addition, radon inhalation inhibits carrageenan-induced inflammatory paw edema, suggesting that radon inhalation has anti-inflammatory effects. Furthermore, radon inhalation inhibits formalin-induced inflammatory pain and chronic constriction injury-induced neuropathic pain, suggesting that radon inhalation relieves pain. Thus, low-dose irradiation very likely activates the defense systems in the body, and therefore, contributes to preventing or reducing ROS-related injuries, which are thought to involve peroxidation.
Collapse
Affiliation(s)
- Takahiro Kataoka
- Graduate School of Health Sciences, Okayama University, Okayama, Japan.
| |
Collapse
|
7
|
Yukawa O, Nakajima T, Miura Y, Ueda J, Ozawa T. Induction of radical scavenging ability and suppression of lipid peroxidation in rat liver microsomes following whole-body, low-dose X-irradiation. Int J Radiat Biol 2009; 81:681-8. [PMID: 16368646 DOI: 10.1080/09553000500401445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
PURPOSE To investigate changes in radical scavenging ability and lipid peroxidation in liver microsomal membranes and cooperative suppression of lipid peroxidation by microsomal and cytosolic radical scavengers, 24 h after whole-body, low-dose X-irradiation of rats. MATERIALS AND METHODS Male Wistar rats were irradiated with 1-50 cGy of X-rays. Liver microsomal radical scavenging ability was determined using the trapping ability of 1,1-diphenyl-2-picrylhydrazyl (DPPH), a stable free radical. Microsomal alpha-tocopherol (Vit.E) content was determined using an electrochemical detector. Microsomal glutathione peroxidase (GPx) activity was determined as the consuming rate of NADPH. Microsomal lipid peroxidation was determined by the thiobarbituric acid method. RESULTS Low molecular weight radical scavenging ability of rat liver microsomes increased 24 h after whole-body, low-dose X-irradiation when alpha-tocopherol was included, showing a maximum level at 5-10 cGy. Microsomal GPx activity also increased 24 h after 5 cGy irradiation. The lipid peroxidation level in microsomes decreased, showing a maximal suppression at 5 cGy. High-dose irradiation-induced microsomal lipid peroxidation was strongly suppressed cooperatively by microsomal and cytosolic antioxidants induced by low-dose irradiation. CONCLUSION Low doses of radiation induce increases in liver microsomal antioxidants, which in turn result in enhanced suppression of microsomal lipid peroxidation cooperatively with cytosolic antioxidants induced by low-dose irradiation.
Collapse
Affiliation(s)
- Osami Yukawa
- Radiation Hazards Research Group, Research Center for Radiation Safety, National Institute of Radiological Sciences, Anagawa, Chiba-shi, Japan
| | | | | | | | | |
Collapse
|
8
|
Du G, Fischer BE, Voss KO, Becker G, Taucher-Scholz G, Kraft G, Thiel G. The Absence of an Early Calcium Response to Heavy-Ion Radiation in Mammalian Cells. Radiat Res 2008; 170:316-26. [DOI: 10.1667/rr1270.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 04/24/2008] [Indexed: 11/03/2022]
|
9
|
Morales-Ramírez P, González-Beltrán F. Different behavior of SCE-eliciting lesions induced by low and high doses of busulfan. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2007; 48:706-14. [PMID: 17896789 DOI: 10.1002/em.20344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Our previous studies suggested a dose-dependent transition in the types of DNA lesions induced by busulfan, as measured using the comet assay and by micronuclei analyses. The aim of the present study was to investigate the dose-dependent induction of different sister-chromatid exchange-eliciting lesions; lesions were distinguished by their efficiency in producing sister-chromatid exchange (SCE), and by their reparability during G1. Synchronously dividing murine salivary gland cells were assayed in vivo. Groups of mice were intraperitoneally injected with either 30 or 80 micromol busulfan/kg body weight solution at early or late G1. The rate of SCE/micromol busulfan/kg body weight obtained by exposure at late G1 with the high dose was twice that of the low dose. SCE induction during early G1 was higher than at late G1 with both doses; only the low-dose response was statistically significant. The frequency distribution of SCEs per cell demonstrated that cells exposed at the late G1 phase showed typical profiles that closely fit a Gaussian curve. However, an irregular profile was obtained for cells treated during early G1, which showed some cells with high-SCE frequency. Cells treated in early G1 have more time to repair lesions before DNA synthesis; therefore, the results suggest that instead of repair, secondary SCE-eliciting lesions during G1 were produced, especially at the lower dose. The results obtained in this study indicate that there are dose-dependent differences in the types of SCE-eliciting lesions induced by busulfan.
Collapse
Affiliation(s)
- Pedro Morales-Ramírez
- Departmento de Biologa, Instituto Nacional de Investigaciones Nucleares, AP 18-1027 México, D.F., México.
| | | |
Collapse
|
10
|
de Toledo SM, Asaad N, Venkatachalam P, Li L, Howell RW, Spitz DR, Azzam EI. Adaptive responses to low-dose/low-dose-rate gamma rays in normal human fibroblasts: the role of growth architecture and oxidative metabolism. Radiat Res 2007; 166:849-57. [PMID: 17149977 DOI: 10.1667/rr0640.1] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2006] [Accepted: 08/02/2006] [Indexed: 11/03/2022]
Abstract
To investigate low-dose/low-dose-rate effects of low-linear energy transfer (LET) ionizing radiation, we used gamma-irradiated cells adapted to grow in a three-dimensional architecture that mimics cell growth in vivo. We determined the cellular, molecular and biochemical changes in these cells. Quiescent normal human fibroblasts were irradiated with single acute or chronic doses (1-10 cGy) of (137)Cs gamma rays. Whereas exposure to an acute dose of 10 cGy increased micronucleus formation, protraction of the dose over 48 h reduced micronucleus frequency to a level similar to or lower than what occurs spontaneously. The protracted treatment also up-regulated the cellular content of the antioxidant glutathione. These changes correlated with modulation of phospho-TP53 (serine 15), a stress marker that was regulated by doses as low as 1 cGy. The DNA damage that occurred after exposure to an acute dose of 10 cGy was protected against in two ways: (1) up-regulation of cellular antioxidant enzyme activity by ectopic overexpression of MnSOD, catalase or glutathione peroxidase, and (2) inhibition of superoxide anion generation by flavin-containing oxidases. These results support a significant role for oxidative metabolism in mediating low-dose radiation effects and demonstrate that cell culture in three dimensions is ideal to investigate radiation-induced adaptive responses. Expression of connexin 43, a constitutive protein of gap junctions, and the G(1) checkpoint were more sensitive to regulation by gamma rays in cells maintained in a three-dimensional than in a two-dimensional configuration.
Collapse
Affiliation(s)
- Sonia M de Toledo
- Department of Radiology, UMDNJ-New Jersey Medical School, Newark, New Jersey 07101, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Yamaoka K. Activation of Antioxidant System by Low Dose Radiation and Its Applicable Possibility for Treatment of Reactive Oxygen Species-Related Diseases. J Clin Biochem Nutr 2006. [DOI: 10.3164/jcbn.39.114] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
12
|
Morales-Ramírez P, Mendiola-Cruz MT. Kinetics of the early adaptive response to gamma rays: induction of a cellular radioprotective mechanism in murine leukocytes in vivo. Biosci Rep 2005; 24:609-16. [PMID: 16158198 DOI: 10.1007/s10540-005-2795-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The aims of the study were to establish the kinetics of the early adaptive response and to determine the minimum adaptive dose of gamma rays capable of inducing this response. The minimum adaptive dose was determined by exposing groups of five BALB/c male mice to an adaptive dose of 0.005 or of 0.02 Gy gamma rays from a 137Cs source and challenge with 1.0 Gy 60 min later. The kinetics of adaptive response induction was established by exposing mice to an adaptive dose of 0.01 Gy, and subsequently to a challenge dose of 1.0 Gy at different times. Blood samples were collected from the tail immediately after exposure to the challenge dose, and the percentage of DNA-damaged cells and the extent of damaged were determined by single cell gel electrophoresis in 300 leukocytes per animal in five mice. The results confirms the capability of an in vivo induction of an early radioprotective process against the DNA-damage produced by gamma rays in murine leukocytes, and allows us to conclude that the minimum adaptive dose lies between 0.005 and 0.01 Gy of gamma rays, and the early adaptive response is induced as early as 30 min after the exposure and persists for at least 18 hr.
Collapse
Affiliation(s)
- Pedro Morales-Ramírez
- Departamento de Biología, Instituto Nacional de Investigaciones Nucleares, Apartado Postal, 18-1027, México, D.F., Mexico.
| | | |
Collapse
|
13
|
Kurozumi R, Kojima S. Increase of intracellular glutathione by low-level NO mediated by transcription factor NF-κB in RAW 264.7 cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1744:58-67. [PMID: 15878398 DOI: 10.1016/j.bbamcr.2004.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Revised: 11/15/2004] [Accepted: 11/15/2004] [Indexed: 11/22/2022]
Abstract
The mechanism underlying the elevation of intracellular glutathione (GSH) in RAW 264.7 cells exposed to low concentrations of sodium nitroprusside (SNP), a well-known nitric oxide (NO) donor, was investigated. The peak of intracellular GSH was reached at 6 h after exposure of the cells to SNP (0.1-0.5 mM), and this was preceded by the induction of mRNA for gamma-glutamylcysteine synthetase (gamma-GCS; the rate-limiting enzyme of de novo GSH synthesis), which peaked at 3 h. N-alpha-Tosyl-L-phenylalanine chloromethyl ketone (TPCK) and caffeic acid phenethyl ester (CAPE), specific inhibitors of NF-kappaB, significantly suppressed the SNP-induced elevation of GSH protein and gamma-GCS mRNA, while curcumin, an inhibitor of AP-1, was less effective. Electrophoretic mobility shift assay (EMSA) showed that SNP exposure markedly increased the DNA binding of NF-kappaB, but not that of AP-1. Deletion or mutagenesis of the NF-kappaB site in the gamma-GCS gene promoter abolished the SNP-induced up-regulation of GSH protein and gamma-GCS mRNA. These results suggest that the elevation of intracellular GSH in RAW 264.7 cells exposed to low concentrations of SNP occurs through the operation of the de novo GSH pathway, and is mediated by transcriptional up-regulation of the gamma-GCS gene, predominantly at the NF-kappaB binding site in its promoter.
Collapse
Affiliation(s)
- Risa Kurozumi
- The Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510, Japan.
| | | |
Collapse
|
14
|
Kurozumi R, Takahashi M, Kojima S. Involvement of Mitochondrial Peroxynitrite in Nitric Oxide-Induced Glutathione Synthesis. Biol Pharm Bull 2005; 28:779-85. [PMID: 15863878 DOI: 10.1248/bpb.28.779] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cells respond to oxidative stress including nitric oxide (NO) by increasing cellular glutathione concentration, as a part of adaptive response against oxidative injury. To elucidate the mechanism by which NO induces glutathione we investigated the reactive oxygen species (ROS) generated in the cell. Treatment of RAW264.7 cells with NO donor, sodium nitroprusside (SNP), resulted in a temporary increase in glutathione in a dose-dependent manner, which peaked between 6 h and 12 h after treatment, whereas expression of gamma-glutamylcysteine synthetase (gamma-GCS) mRNA peaked around 3 h after treatment. The increase was inhibited by NO scavengers, oxyhemoglobin and carboxyl-2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO). N-Acetyl-L-cysteine (NAC) also reduced the increase in glutathione to some extent, whereas both peroxynitrite scavenger ebselen and hydroxyl radical scavenger DMSO inhibited the increase in glutathione in a dose-dependent manner and complete inhibition was observed. Hydrogen peroxide exogenously added to the cell did not increase either glutathione or gamma-GCS expression at any concentration, indicating that involvement of hydrogen peroxide is not likely. Flow cytometric analysis showed that SNP induced a marked dose-dependent increase in Rhodamine123 fluorescence, which was completely inhibited by ebselen in a dose-dependent manner, whereas, little increase in 2',7'-dichlorofluorescin (DCF) fluorescence was observed. Generation of peroxynitrite in mitochondria by SNP was confirmed by elevated level of nitrotyrosine in a mitochondria fraction isolated from SNP-treated cells, and the elevation was completely inhibited by ebselen as well. These results suggest that induction of glutathione (GSH) synthesis by SNP treatment is mediated by peroxynitrite generated in mitochondria.
Collapse
Affiliation(s)
- Risa Kurozumi
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba 278-8510, Japan
| | | | | |
Collapse
|
15
|
Miura Y. Oxidative stress, radiation-adaptive responses, and aging. JOURNAL OF RADIATION RESEARCH 2004; 45:357-372. [PMID: 15613781 DOI: 10.1269/jrr.45.357] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Organisms living in an aerobic environment were forced to evolve effective cellular strategies to detoxify reactive oxygen species. Besides diverse antioxidant enzymes and compounds, DNA repair enzymes, and disassembly systems, which remove damaged proteins, regulation systems that control transcription, translation, and activation have also been developed. The adaptive responses, especially those to radiation, are defensive regulation mechanisms by which oxidative stress (conditioning irradiation) elicits a response against damage because of subsequent stress (challenging irradiation). Although many researchers have investigated these molecular mechanisms, they remain obscure because of their complex signaling pathways and the involvement of various proteins. This article reviews the factors concerned with radiation-adaptive response, the signaling pathways activated by conditioning irradiation, and the effects of aging on radiation-adaptive response. The proteomics approach is also introduced, which is a useful method for studying stress response in cells.
Collapse
Affiliation(s)
- Yuri Miura
- Redox regulation research group, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku. Tokyo, Japan.
| |
Collapse
|
16
|
Kojima S, Ishida H, Takahashi M, Yamaoka K. Elevation of glutathione induced by low-dose gamma rays and its involvement in increased natural killer activity. Radiat Res 2002; 157:275-80. [PMID: 11839089 DOI: 10.1667/0033-7587(2002)157[0275:eogibl]2.0.co;2] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We examined the relationship between the induction of an increase in the level of glutathione and the elevation of natural killer (NK) activity in mouse splenocytes by a low dose of gamma rays. The glutathione levels in mouse splenocytes increased significantly between 2 h and 6 h after whole-body gamma irradiation at 0.5 Gy, peaked at 4 h, and then decreased almost to the level before irradiation by 12 h postirradiation. A significant enhancement of NK activity was found in the splenocytes obtained from whole-body-irradiated mice between 4 and 6 h postirradiation. Reduced glutathione (GSH) added exogenously to splenocytes obtained from normal mice enhanced both the total cellular glutathione content and the NK activity in a dose-dependent manner. Other precursors of de novo GSH synthesis, such as cysteine, N-acetylcysteine and oxidized glutathione, also increased the activity. These enhancements were completely blocked by buthionine sulfoximine, an inhibitor of de novo GSH synthesis. We conclude that the induction of endogenous glutathione in living cells immediately after low-dose gamma irradiation is at least partially responsible for the appearance of enhanced NK activity.
Collapse
Affiliation(s)
- Shuji Kojima
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda-shi, Chiba 278-0022, Japan.
| | | | | | | |
Collapse
|
17
|
Kurozumi R, Kojima S. Low-level Nitric Oxide Blunts Oxidant Injury via Up-regulating Glutathione Synthes. ACTA ACUST UNITED AC 2002. [DOI: 10.1248/jhs.48.140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Risa Kurozumi
- Faculty of Pharmaceutical Sciences, Tokyo University of Science
| | - Shuji Kojima
- Faculty of Pharmaceutical Sciences, Tokyo University of Science
| |
Collapse
|