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Lin X, Wei J, Nie J, Bai F, Zhu X, Zhuo L, Lu Z, Huang Q. Inhibition of RKIP aggravates thioacetamide-induced acute liver failure in mice. Exp Ther Med 2018; 16:2992-2998. [PMID: 30214516 PMCID: PMC6125827 DOI: 10.3892/etm.2018.6542] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/31/2017] [Indexed: 11/17/2022] Open
Abstract
Accumulating evidence has indicated that Raf kinase inhibitor protein (RKIP) is involved in several intracellular signaling pathways; its abnormal expression is associated with tumor progression and metastasis in several human neoplasms. However, the role of RKIP in acute liver injury has remained elusive. In the present study, acute liver failure was induced by thioacetamide in mice, and locostatin was used to interfere with RKIP expression. It was found that RKIP expression was significantly inhibited by locostatin. Down-regulation of RKIP expression resulted in severe liver injury and extensive release of alanine aminotransferase and aspartate aminotransferase. In addition, reduced RKIP expression significantly enhanced the levels of reactive oxygen species and the content of pro-inflammatory factors such as tumor necrosis factor-α as well as interleukin-6 and −1β, and decreased the levels of nuclear factor E2-related factor-2 and heme oxygenase-1. Furthermore, down-regulation of RKIP promoted the activation of the nuclear factor-κB and extracellular signal-regulated kinase signaling pathways. In conclusion, the present study indicates an inverse correlation between RKIP level and the degree of hepatic injury, that is, a decrease in RKIP expression may exacerbate acute liver failure.
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Affiliation(s)
- Xing Lin
- Pharmaceutical College and Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Jinbin Wei
- Pharmaceutical College and Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Jinlan Nie
- Pharmaceutical College and Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Facheng Bai
- Pharmaceutical College and Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Xunshuai Zhu
- Pharmaceutical College and Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Lang Zhuo
- Department of Bioengineering, Institute of Bioengineering and Nanotechnology, Singapore 169483, Republic of Singapore
| | - Zhongpeng Lu
- Department of Biochemistry, University of Arkansas Medical School, Little Rock, AR 72205-7199, USA
| | - Quanfang Huang
- Department of Pharmacy, The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning, Guangxi 530023, P.R. China
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2
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Lu Y, Cederbaum AI. Cytochrome P450s and Alcoholic Liver Disease. Curr Pharm Des 2018; 24:1502-1517. [PMID: 29637855 PMCID: PMC6053342 DOI: 10.2174/1381612824666180410091511] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 03/30/2018] [Accepted: 04/06/2018] [Indexed: 12/19/2022]
Abstract
Alcohol consumption causes liver diseases, designated as Alcoholic Liver Disease (ALD). Because alcohol is detoxified by alcohol dehydrogenase (ADH), a major ethanol metabolism system, the development of ALD was initially believed to be due to malnutrition caused by alcohol metabolism in liver. The discovery of the microsomal ethanol oxidizing system (MEOS) changed this dogma. Cytochrome P450 enzymes (CYP) constitute the major components of MEOS. Cytochrome P450 2E1 (CYP2E1) in MEOS is one of the major ROS generators in liver and is considered to be contributive to ALD. Our labs have been studying the relationship between CYP2E1 and ALD for many years. Recently, we found that human CYP2A6 and its mouse analog CYP2A5 are also induced by alcohol. In mice, the alcohol induction of CYP2A5 is CYP2E1-dependent. Unlike CYP2E1, CYP2A5 protects against the development of ALD. The relationship of CYP2E1, CYP2A5, and ALD is a major focus of this review.
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Affiliation(s)
- Yongke Lu
- Department of Health Sciences, College of Public Health, East Tennessee State University
- Center of Excellence for Inflammation, Infectious Disease and Immunity, East Tennessee State University
| | - Arthur I. Cederbaum
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai
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Parker L, Shaw CS, Stepto NK, Levinger I. Exercise and Glycemic Control: Focus on Redox Homeostasis and Redox-Sensitive Protein Signaling. Front Endocrinol (Lausanne) 2017; 8:87. [PMID: 28529499 PMCID: PMC5418238 DOI: 10.3389/fendo.2017.00087] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/04/2017] [Indexed: 12/16/2022] Open
Abstract
Physical inactivity, excess energy consumption, and obesity are associated with elevated systemic oxidative stress and the sustained activation of redox-sensitive stress-activated protein kinase (SAPK) and mitogen-activated protein kinase signaling pathways. Sustained SAPK activation leads to aberrant insulin signaling, impaired glycemic control, and the development and progression of cardiometabolic disease. Paradoxically, acute exercise transiently increases oxidative stress and SAPK signaling, yet postexercise glycemic control and skeletal muscle function are enhanced. Furthermore, regular exercise leads to the upregulation of antioxidant defense, which likely assists in the mitigation of chronic oxidative stress-associated disease. In this review, we explore the complex spatiotemporal interplay between exercise, oxidative stress, and glycemic control, and highlight exercise-induced reactive oxygen species and redox-sensitive protein signaling as important regulators of glucose homeostasis.
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Affiliation(s)
- Lewan Parker
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- *Correspondence: Lewan Parker, ,
| | - Christopher S. Shaw
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, VIC, Australia
| | - Nigel K. Stepto
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- Monash Centre for Health Research and Implementation, School of Public Health and Preventative Medicine, Monash University, Clayton, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University and Western Health, St. Albans, VIC, Australia
| | - Itamar Levinger
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University and Western Health, St. Albans, VIC, Australia
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4
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CYP2E1- and TNFalpha/LPS-Induced Oxidative Stress and MAPK Signaling Pathways in Alcoholic Liver Disease. CURRENT PATHOBIOLOGY REPORTS 2015. [DOI: 10.1007/s40139-015-0092-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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. EXP CLIN TRANSPLANT 2015; 13. [DOI: 10.6002/ect.mesot2014.p7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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6
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CYP2E1 Sensitizes the Liver to LPS- and TNF α-Induced Toxicity via Elevated Oxidative and Nitrosative Stress and Activation of ASK-1 and JNK Mitogen-Activated Kinases. Int J Hepatol 2012; 2012:582790. [PMID: 22028977 PMCID: PMC3199085 DOI: 10.1155/2012/582790] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 08/10/2011] [Accepted: 08/10/2011] [Indexed: 01/04/2023] Open
Abstract
The mechanisms by which alcohol causes cell injury are not clear. A major mechanism is the role of lipid peroxidation and oxidative stress in alcohol toxicity. Many pathways have been suggested to play a role in how alcohol induces oxidative stress. Considerable attention has been given to alcohol elevated production of lipopolysaccharide (LPS) and TNFα and to alcohol induction of CYP2E1. These two pathways are not exclusive of each other; however, interactions between them, have not been extensively evaluated. Increased oxidative stress from induction of CYP2E1 sensitizes hepatocytes to LPS and TNFα toxicity and oxidants, activation of inducible nitric oxide synthase and p38 and JNK MAP kinases, and mitochondrial dysfunction are downstream mediators of this CYP2E1-LPS/TNFα-potentiated hepatotoxicity. This paper will summarize studies showing potentiated interactions between these two risk factors in promoting liver injury and the mechanisms involved including activation of the mitogen-activated kinase kinase kinase ASK-1. Decreasing either cytosolic or mitochondrial thioredoxin in HepG2 cells expressing CYP2E1 causes loss of cell viability and elevated oxidative stress via an ASK-1/JNK-dependent mechanism. We hypothesize that similar interactions occur as a result of ethanol induction of CYP2E1 and TNFα.
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McCubrey JA, Steelman LS, Kempf CR, Chappell WH, Abrams SL, Stivala F, Malaponte G, Nicoletti F, Libra M, Bäsecke J, Maksimovic-Ivanic D, Mijatovic S, Montalto G, Cervello M, Cocco L, Martelli AM. Therapeutic resistance resulting from mutations in Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR signaling pathways. J Cell Physiol 2011; 226:2762-81. [PMID: 21302297 DOI: 10.1002/jcp.22647] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chemotherapy remains a commonly used therapeutic approach for many cancers. Indeed chemotherapy is relatively effective for treatment of certain cancers and it may be the only therapy (besides radiotherapy) that is appropriate for certain cancers. However, a common problem with chemotherapy is the development of drug resistance. Many studies on the mechanisms of drug resistance concentrated on the expression of membrane transporters and how they could be aberrantly regulated in drug resistant cells. Attempts were made to isolate specific inhibitors which could be used to treat drug resistant patients. Unfortunately most of these drug transporter inhibitors have not proven effective for therapy. Recently the possibilities of more specific, targeted therapies have sparked the interest of clinical and basic researchers as approaches to kill cancer cells. However, there are also problems associated with these targeted therapies. Two key signaling pathways involved in the regulation of cell growth are the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways. Dysregulated signaling through these pathways is often the result of genetic alterations in critical components in these pathways as well as mutations in upstream growth factor receptors. Furthermore, these pathways may be activated by chemotherapeutic drugs and ionizing radiation. This review documents how their abnormal expression can contribute to drug resistance as well as resistance to targeted therapy. This review will discuss in detail PTEN regulation as this is a critical tumor suppressor gene frequently dysregulated in human cancer which contributes to therapy resistance. Controlling the expression of these pathways could improve cancer therapy and ameliorate human health.
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Affiliation(s)
- James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, North Carolina 27858, USA.
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8
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Nogueira NPDA, de Souza CF, Saraiva FMDS, Sultano PE, Dalmau SR, Bruno RE, de Lima Sales Gonçalves R, Laranja GAT, Leal LHM, Coelho MGP, Masuda CA, Oliveira MF, Paes MC. Heme-induced ROS in Trypanosoma cruzi activates CaMKII-like that triggers epimastigote proliferation. One helpful effect of ROS. PLoS One 2011; 6:e25935. [PMID: 22022475 PMCID: PMC3191175 DOI: 10.1371/journal.pone.0025935] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Accepted: 09/14/2011] [Indexed: 11/18/2022] Open
Abstract
Heme is a ubiquitous molecule that has a number of physiological roles. The toxic effects of this molecule have been demonstrated in various models, based on both its pro-oxidant nature and through a detergent mechanism. It is estimated that about 10 mM of heme is released during blood digestion in the blood-sucking bug's midgut. The parasite Trypanosoma cruzi, the agent of Chagas' disease, proliferates in the midgut of the insect vector; however, heme metabolism in trypanosomatids remains to be elucidated. Here we provide a mechanistic explanation for the proliferative effects of heme on trypanosomatids. Heme, but not other porphyrins, induced T. cruzi proliferation, and this phenomenon was accompanied by a marked increase in reactive oxygen species (ROS) formation in epimastigotes when monitored by ROS-sensitive fluorescent probes. Heme-induced ROS production was time-and concentration-dependent. In addition, lipid peroxidation and the formation of 4-hydroxy-2-nonenal (4-HNE) adducts with parasite proteins were increased in epimastigotes in the presence of heme. Conversely, the antioxidants urate and GSH reversed the heme-induced ROS. Urate also decreased parasite proliferation. Among several protein kinase inhibitors tested only specific inhibitors of CaMKII, KN93 and Myr-AIP, were able to abolish heme-induced ROS formation in epimastigotes leading to parasite growth impairment. Taken together, these data provide new insight into T. cruzi- insect vector interactions: heme, a molecule from the blood digestion, triggers epimastigote proliferation through a redox-sensitive signalling mechanism.
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Affiliation(s)
- Natália Pereira de Almeida Nogueira
- Laboratório de Artrópodos Hematófagos, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
| | - Cintia Fernandes de Souza
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Francis Monique de Souza Saraiva
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Pedro Elias Sultano
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Sergio Ranto Dalmau
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Roberta Eitler Bruno
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Renata de Lima Sales Gonçalves
- Laboratório de Bioquímica Redox - Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
| | - Gustavo Augusto Travassos Laranja
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Luís Henrique Monteiro Leal
- Laboratório de Microscopia e Processamento de Imagens, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Marsen Garcia Pinto Coelho
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
| | - Claudio A. Masuda
- Laboratório de Biologia Molecular de Leveduras, Programa de Biologia Molecular e Biotecnologia, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
| | - Marcus F. Oliveira
- Laboratório de Bioquímica Redox - Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
- Laboratório de Inflamação e Metabolismo, Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem (INBEB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
| | - Marcia Cristina Paes
- Laboratório de Interação Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcântara Gomes (IBRAG), Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brasil
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular (INCT-EM), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil
- * E-mail:
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9
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Steelman LS, Chappell WH, Abrams SL, Kempf RC, Long J, Laidler P, Mijatovic S, Maksimovic-Ivanic D, Stivala F, Mazzarino MC, Donia M, Fagone P, Malaponte G, Nicoletti F, Libra M, Milella M, Tafuri A, Bonati A, Bäsecke J, Cocco L, Evangelisti C, Martelli AM, Montalto G, Cervello M, McCubrey JA. Roles of the Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways in controlling growth and sensitivity to therapy-implications for cancer and aging. Aging (Albany NY) 2011; 3:192-222. [PMID: 21422497 PMCID: PMC3091517 DOI: 10.18632/aging.100296] [Citation(s) in RCA: 457] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dysregulated signaling through the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways is often the result of genetic alterations in critical components in these pathways or upstream activators. Unrestricted cellular proliferation and decreased sensitivity to apoptotic-inducing agents are typically associated with activation of these pro-survival pathways. This review discusses the functions these pathways have in normal and neoplastic tissue growth and how they contribute to resistance to apoptotic stimuli. Crosstalk and commonly identified mutations that occur within these pathways that contribute to abnormal activation and cancer growth will also be addressed. Finally the recently described roles of these pathways in cancer stem cells, cellular senescence and aging will be evaluated. Controlling the expression of these pathways could ameliorate human health.
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Affiliation(s)
- Linda S Steelman
- Department of Microbiology and Immunology, East Carolina University, Greenville, NC 27858, USA
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Abstract
The Ras/Raf/mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway is often implicated in sensitivity and resistance to leukemia therapy. Dysregulated signaling through the Ras/Raf/MEK/ERK pathway is often the result of genetic alterations in critical components in this pathway as well as mutations at upstream growth factor receptors. Unrestricted leukemia proliferation and decreased sensitivity to apoptotic-inducing agents and chemoresistance are typically associated with activation of pro-survival pathways. Mutations in this pathway and upstream signaling molecules can alter sensitivity to small molecule inhibitors targeting components of this cascade as well as to inhibitors targeting other key pathways (for example, phosphatidylinositol 3 kinase (PI3K)/phosphatase and tensin homologue deleted on chromosome 10 (PTEN)/Akt/mammalian target of rapamycin (mTOR)) activated in leukemia. Similarly, PI3K mutations can result in resistance to inhibitors targeting the Ras/Raf/MEK/ERK pathway, indicating important interaction points between the pathways (cross-talk). Furthermore, the Ras/Raf/MEK/ERK pathway can be activated by chemotherapeutic drugs commonly used in leukemia therapy. This review discusses the mechanisms by which abnormal expression of the Ras/Raf/MEK/ERK pathway can contribute to drug resistance as well as resistance to targeted leukemia therapy. Controlling the expression of this pathway could improve leukemia therapy and ameliorate human health.
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Csordás G, Hajnóczky G. SR/ER-mitochondrial local communication: calcium and ROS. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1352-62. [PMID: 19527680 DOI: 10.1016/j.bbabio.2009.06.004] [Citation(s) in RCA: 227] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 06/04/2009] [Accepted: 06/05/2009] [Indexed: 02/07/2023]
Abstract
Mitochondria form junctions with the sarco/endoplasmic reticulum (SR/ER), which support signal transduction and biosynthetic pathways and affect organellar distribution. Recently, these junctions have received attention because of their pivotal role in mediating calcium signal propagation to the mitochondria, which is important for both ATP production and mitochondrial cell death. Many of the SR/ER-mitochondrial calcium transporters and signaling proteins are sensitive to redox regulation and are directly exposed to the reactive oxygen species (ROS) produced in the mitochondria and SR/ER. Although ROS has been emerging as a novel signaling entity, the redox signaling of the SR/ER-mitochondrial interface is yet to be elucidated. We describe here possible mechanisms of the mutual interaction between local Ca(2+) and ROS signaling in the control of SR/ER-mitochondrial function.
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Affiliation(s)
- György Csordás
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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12
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Merckx A, Bouyer G, Thomas SLY, Langsley G, Egée S. Anion channels in Plasmodium-falciparum-infected erythrocytes and protein kinase A. Trends Parasitol 2009; 25:139-44. [PMID: 19200784 DOI: 10.1016/j.pt.2008.12.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 12/01/2008] [Accepted: 12/10/2008] [Indexed: 01/09/2023]
Abstract
By replicating within red blood cells, malaria parasites are largely hidden from immune recognition; however, in the cells, nutrients are limiting and hazardous metabolic end products can rapidly accumulate. Therefore, to survive within erythrocytes, parasites alter the permeability of the host plasma membrane, either by upregulating existing transporters or by creating new permeation pathways. Recent electrophysiological studies of Plasmodium-infected erythrocytes have demonstrated that membrane permeability is mediated by transmembrane transport through ion channels in the infected erythrocyte. This article discusses the evidence and controversies concerning the nature of these channels and surveys the potential role of phosphorylation in activating anion channels that could be important in developing novel strategies for future malarial chemotherapies.
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Affiliation(s)
- Anaïs Merckx
- Institut Cochin, INSERM U567, Université Paris Descartes, CNRS (UMR 8104), Paris, France
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13
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Ancha HR, Kurella RR, McKimmey CC, Lightfoot S, Harty RF. Luminal antioxidants enhance the effects of mesalamine in the treatment of chemically induced colitis in rats. Exp Biol Med (Maywood) 2008; 233:1301-8. [PMID: 18703751 DOI: 10.3181/0805-rm-140] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
UNLABELLED Previous experiments in rats with chemically induced colitis have shown that the antioxidant N-acetylcysteine plus mesalamine (5-ASA) exerted a significantly greater therapeutic effect in promoting mucosal healing when compared to either agent alone. The aims of the present study were to compare the effects of three antioxidants plus mesalamine vs. 5-ASA alone in treatment of colitis induced by trinitrobenzene sulfonic acid (TNBS) in rats. METHODS Three days following induction of TNBS colitis, rats received 8 days of rectal therapy with 5-ASA, or 5-ASA plus vitamin C (ascorbic acid), 5-ASA plus phenyl butylnitrone (PBN) and 5-ASA plus vitamin E (alpha-tocopherol). Distal colonic tissues were examined for microscopic colitis and myeloperoxidase (MPO) activity. RESULTS Global assessments of microscopic colitis induced by TNBS indicated that 5-ASA alone significantly changed colonic injury by -31%. Combination therapy with ascorbic acid plus 5-ASA or alpha-tocopherol plus 5-ASA caused further significant change in TNBS colitis by -65 and -82%, respectively. Each of these values was significantly below scores observed with 5-ASA as monotherapy. Reduction in colitis with PBN plus 5-ASA was not different from 5-ASA alone. MPO activity was decreased significantly in response to monotherapy with 5-ASA and each of the antioxidants plus 5-ASA when compared to TNBS. alpha-Tocopherol plus 5-ASA, however, was the only treatment strategy that reduced significantly MPO activity below that recorded for 5-ASA alone. In conclusion, our results indicate that antioxidants other than N-acetylcysteine significantly enhance the therapeutic effectiveness of 5-ASA in the treatment of TNBS colitis. alpha-Tocopherol plus 5-ASA exerted profound anti-inflammatory and reparative effects upon colitis induced by TNBS.
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Affiliation(s)
- Hanumantha R Ancha
- Department of Gastroenterology, University of Oklahoma Health Sciences Center, 920 Oklahoma City, OK 73104, USA
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Pi Y, Goldenthal MJ, Marín-García J. Mitochondrial channelopathies in aging. J Mol Med (Berl) 2007; 85:937-51. [PMID: 17426949 DOI: 10.1007/s00109-007-0190-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Revised: 01/20/2007] [Accepted: 02/16/2007] [Indexed: 12/15/2022]
Abstract
Defects in ion channels (channelopathies) are increasingly found in a large spectrum of human pathologies including aging. Mutations in genes encoding ion channel proteins, which disrupt channel function, are the most commonly identified cause of channelopathies. Mutations in associated proteins, alterations in the expression of ion channels, or changes in the activity of non-mutated channel genes or associated proteins can also produce acquired channelopathies. Mitochondria, the powerhouse of the cells, are considered to be the most important cellular organelles to contribute to aging mainly because of their role in the production of reactive oxygen species in the initiation of apoptotic cell remodeling and in efficient ATP synthesis. During the past 50 years, multiple ion channels or transporters have been found in mitochondria, and the relationship between the activity of these channels and cellular aging, as well as the overall cellular biological function, has been intensively studied in a number of cell types and animal models. In this review, we discuss the better characterized mitochondrial ion channels whose dysfunction (mitochondrial channelopathies) may affect or accelerate the aging processes. These channels include the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)), Ca(2+) transporters, voltage-dependent anion channel, and the mitochondrial permeability transition pore (mitoPTP).
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Affiliation(s)
- YeQing Pi
- The Molecular Cardiology and Neuromuscular Institute, 75 Raritan Avenue, Highland Park, NJ 08904, USA
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