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Lee YJ, Heo JY, Kim DS, Choi YS, Kim S, Nam HS, Lee SH, Cho MK. Curcumin Enhances the Anticancer Effects of Binimetinib on Melanoma Cells by Inducing Mitochondrial Dysfunction and Cell Apoptosis with Necroptosis. Ann Dermatol 2023; 35:217-228. [PMID: 37290955 DOI: 10.5021/ad.22.200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/19/2023] [Accepted: 01/24/2023] [Indexed: 06/10/2023] Open
Abstract
BACKGROUND Recent studies suggest that MEK1/2 inhibitors, including binimetinib, significantly improve malignant melanoma (MM) patient survival. Growing evidence suggests that phytochemicals, especially curcumin, can overcome drug resistance in cancer cells through a variety of mechanisms. OBJECTIVE This study aims to examine curcumin's efficacy in vitro combined with binimetinib in human MM cells. METHODS We used 2D monolayer and 3D spheroid human epidermal melanocyte culture models, HEMn-MP (human epidermal melanocytes, neonatal, moderately pigmented), and two human MM cell lines, G361 and SK-MEL-2, to evaluate cell viability, proliferation, migration, death, and reactive oxygen species (ROS) production following single therapy treatment, with either curcumin or binimetinib, or a combination of both. RESULTS Compared to MM cells treated with single therapy, those with combination therapy showed significantly decreased cell viability and increased ROS production. We observed apoptosis following both single and combination therapies. However only those who had had combination therapy had necroptosis. CONCLUSION Collectively, our data demonstrates that curcumin exerts significant synergistic anticancer effects on MM cells by inducing ROS and necroptosis when combined with binimetinib. Therefore, a strategy of adding curcumin to conventional anticancer agents holds promise for treating MM.
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Affiliation(s)
- Yoon Jin Lee
- Department of Biochemistry, Soonchunhyang University College of Medicine, Cheonan, Korea
- Division of Molecular Cancer Research, Soonchunhyang Medical Research Institute, Soonchunhyang University, Cheonan, Korea
| | - Jae Young Heo
- Department of Dermatology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Dong Sung Kim
- Department of Dermatology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Yu Sung Choi
- Department of Dermatology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Sooyoung Kim
- Department of Dermatology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Hae Seon Nam
- Division of Molecular Cancer Research, Soonchunhyang Medical Research Institute, Soonchunhyang University, Cheonan, Korea
| | - Sang Han Lee
- Department of Biochemistry, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Moon Kyun Cho
- Department of Dermatology, Soonchunhyang University Seoul Hospital, Seoul, Korea.
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Tyagi A, Haq S, Ramakrishna S. Redox regulation of DUBs and its therapeutic implications in cancer. Redox Biol 2021; 48:102194. [PMID: 34814083 PMCID: PMC8608616 DOI: 10.1016/j.redox.2021.102194] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/19/2021] [Indexed: 02/06/2023] Open
Abstract
Reactive oxygen species (ROS) act as a double-edged sword in cancer, where low levels of ROS are beneficial but excessive accumulation leads to cancer progression. Elevated levels of ROS in cancer are counteracted by the antioxidant defense system. An imbalance between ROS generation and the antioxidant system alters gene expression and cellular signaling, leading to cancer progression or death. Post-translational modifications, such as ubiquitination, phosphorylation, and SUMOylation, play a critical role in the maintenance of ROS homeostasis by controlling ROS production and clearance. Recent evidence suggests that deubiquitinating enzymes (DUBs)-mediated ubiquitin removal from substrates is regulated by ROS. ROS-mediated oxidation of the catalytic cysteine (Cys) of DUBs, leading to their reversible inactivation, has emerged as a key mechanism regulating DUB-controlled cellular events. A better understanding of the mechanism by which DUBs are susceptible to ROS and exploring the ways to utilize ROS to pharmacologically modulate DUB-mediated signaling pathways might provide new insight for anticancer therapeutics. This review assesses the recent findings regarding ROS-mediated signaling in cancers, emphasizes DUB regulation by oxidation, highlights the relevant recent findings, and proposes directions of future research based on the ROS-induced modifications of DUB activity.
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Affiliation(s)
- Apoorvi Tyagi
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, 04763, South Korea
| | - Saba Haq
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, 04763, South Korea
| | - Suresh Ramakrishna
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, 04763, South Korea; College of Medicine, Hanyang University, Seoul, 04763, South Korea.
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Krasovec G, Karaiskou A, Quéinnec É, Chambon JP. Comparative transcriptomic analysis reveals gene regulation mediated by caspase activity in a chordate organism. BMC Mol Cell Biol 2021; 22:51. [PMID: 34615460 PMCID: PMC8495957 DOI: 10.1186/s12860-021-00388-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 08/12/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Apoptosis is a caspase regulated cell death present in all metazoans defined by a conserved set of morphological features. A well-described function of apoptosis is the removal of excessive cells during development and homeostasis. Recent studies have shown an unexpected signalling property of apoptotic cells, affecting cell fate and/or behaviour of neighbouring cells. In contrast to the apoptotic function of cell elimination, this new role of apoptosis is not well understood but seems caspase-dependent. To deepen our understanding of apoptotic functions, it is necessary to work on a biological model with a predictable apoptosis pattern affecting cell fate and/or behaviour. The tunicate Ciona intestinalis has a bi-phasic life cycle with swimming larvae which undergo metamorphosis after settlement. Previously, we have shown that the tail regression step during metamorphosis, characterized by a predictable polarized apoptotic wave, ensures elimination of most tail cells and controls primordial germ cells survival and migration. RESULTS We performed differential transcriptomic analysis between control metamorphosing larvae and larvae treated with the pan-caspase inhibitor Z-VAD-fmk in order to explore the transcriptional control of apoptotic cells on neighbouring cells that survive and migrate. When caspase activity was impaired, genes known to be involved in metamorphosis were downregulated along with other implicated in cell migration and survival molecular pathways. CONCLUSION We propose these results as a confirmation that apoptotic cells can control surrounding cells fate and as a reference database to explore novel apoptotic functions in animals, including those related to migration and differentiation.
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Affiliation(s)
- Gabriel Krasovec
- Institut de Systématique, Evolution, Biodiversité (ISYEB), UMR 7205, Sorbonne Université, Muséum National d'histoire Naturelle, CNRS, EPHE, 7 Quai St-Bernard, F-75252, Paris Cedex 05, France. .,Center for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.
| | - Anthi Karaiskou
- INSERM UMRS_938, Centre de recherche Saint-Antoine (CRSA), Sorbonne Université, Paris, France
| | - Éric Quéinnec
- Institut de Systématique, Evolution, Biodiversité (ISYEB), UMR 7205, Sorbonne Université, Muséum National d'histoire Naturelle, CNRS, EPHE, 7 Quai St-Bernard, F-75252, Paris Cedex 05, France
| | - Jean-Philippe Chambon
- Centre de Recherche de Biologie Cellulaire de Montpellier (CRBM), Montpellier Univ., CNRS, 34000, Montpellier, France
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Musaogullari A, Mandato A, Chai YC. Role of Glutathione Depletion and Reactive Oxygen Species Generation on Caspase-3 Activation: A Study With the Kinase Inhibitor Staurosporine. Front Physiol 2020; 11:998. [PMID: 32982774 PMCID: PMC7485172 DOI: 10.3389/fphys.2020.00998] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/22/2020] [Indexed: 01/11/2023] Open
Abstract
Oxidative stress is known to contribute to the progression of apoptosis. Staurosporine is a broad-spectrum inducer of apoptosis, but its mechanism of action is not well understood. The goal of the present work was to elucidate the role of glutathione and reactive oxygen species (ROS) in the execution of staurosporine-induced apoptosis. HeLa cells were treated with staurosporine at 1 μM for up to 4 h. The concentration of glutathione, generation of ROS, and activation of caspase-3 were measured. The introduction of staurosporine significantly decreased the concentration of cellular glutathione and increased the presence of ROS after 3 h. These findings were concurrent with the activation of caspase-3. Interestingly, pre-treatment of cells with N-acetylcysteine, a precursor of glutathione, and a thiol antioxidant failed to block the depletion of glutathione, generation of ROS, and activation of caspase-3. Collectively, these results suggest that the cellular redox status may be one of the critical factors of the apoptotic pathway leading to caspase-3 activation by staurosporine.
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Affiliation(s)
- Aysenur Musaogullari
- Department of Chemistry, John Carroll University, University Heights, OH, United States
| | - Alysia Mandato
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, United States
| | - Yuh-Cherng Chai
- Department of Chemistry, John Carroll University, University Heights, OH, United States
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5
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Islam MI, Nagakannan P, Ogungbola O, Djordjevic J, Albensi BC, Eftekharpour E. Thioredoxin system as a gatekeeper in caspase-6 activation and nuclear lamina integrity: Implications for Alzheimer's disease. Free Radic Biol Med 2019; 134:567-580. [PMID: 30769159 DOI: 10.1016/j.freeradbiomed.2019.02.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/28/2019] [Accepted: 02/10/2019] [Indexed: 02/01/2023]
Abstract
Recent reports in pathophysiology of neurodegenerative diseases (ND) have linked nuclear lamina degradation/deficits to neuronal cell death. Lamin-B1 damage is specifically involved in this process leading to nuclear envelope invagination and heterochromatin rearrangement. The underlying mechanisms involved in these events are not yet defined. In this study, while examining the effect of Thioredoxin-1(Trx1) inhibition on cell death in a model of oxidative stress, we noted robust nuclear invagination in SH-SY5Y cells. Evaluation of nuclear lamina proteins revealed lamin-B1 cleavage that was prevented by caspase-6 (CASP6) inhibitor and exacerbated after pharmacologic/genetic inhibition of Trx1 system, but not after glutathione depletion. Activation of CASP6 was upstream of CASP3/7 activation and its inhibition was sufficient to prevent cell death in our system. The effect of Trx1 redox status on CASP6 activation was assessed by administration of reduced/oxidized forms in cell-free nuclei preparation and purified enzymatic assays. Although reduced Trx1 decreased CASP6 enzymatic activity and lamin-B1 cleavage, the fully oxidized Trx1 showed opposite effects. The enhanced CASP6 activation was also associated with lower levels of DJ-1, a neuroprotective and master regulator of cellular antioxidants. The implication of our findings in ND pathophysiology was strengthened with detection of lower Trx1 levels in the hippocampi tissue of a mouse model of Alzheimer's disease. This coincided with higher CASP6 activation resulting in increased lamin-B1 and DJ-1 depletion. This study provides a first mechanistic explanation for the key regulatory role of Trx1 as a gatekeeper in activation of CASP6 and induction of nuclear invagination, an important player in ND pathophysiology.
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Affiliation(s)
- Md Imamul Islam
- Regenerative Medicine Program and Spinal Cord Research Centre, Canada; Dept. Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Pandian Nagakannan
- Regenerative Medicine Program and Spinal Cord Research Centre, Canada; Dept. Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Olamide Ogungbola
- Regenerative Medicine Program and Spinal Cord Research Centre, Canada; Dept. Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Jelena Djordjevic
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research, Winnipeg, Manitoba, Canada; Department of Pharmacology and Therapeutics, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Benedict C Albensi
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research, Winnipeg, Manitoba, Canada; Department of Pharmacology and Therapeutics, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Eftekhar Eftekharpour
- Regenerative Medicine Program and Spinal Cord Research Centre, Canada; Dept. Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada.
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Cancer-Associated Function of 2-Cys Peroxiredoxin Subtypes as a Survival Gatekeeper. Antioxidants (Basel) 2018; 7:antiox7110161. [PMID: 30423872 PMCID: PMC6262534 DOI: 10.3390/antiox7110161] [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: 09/27/2018] [Revised: 11/02/2018] [Accepted: 11/07/2018] [Indexed: 12/15/2022] Open
Abstract
Cancer cells are abnormal cells that do not comply with tissue homeostasis but undergo uncontrolled proliferation. Such abnormality is driven mostly by somatic mutations on oncogenes and tumor suppressors. Cancerous mutations show intra-tumoral heterogeneity across cancer types and eventually converge into the self-activation of proliferative signaling. While transient production of intracellular reactive oxygen species (ROS) is essential for cell signaling, its persistent production is cytotoxic. Thus, cancer cells require increased levels of intracellular ROS for continuous proliferation, but overexpress cellular peroxidase enzymes, such as 2-Cys peroxiredoxins, to maintain ROS homeostasis. However, suppression of 2-Cys peroxiredoxins has also been reported in some metastatic cancers. Hence, the cancer-associated functions of 2-Cys peroxiredoxins must be illuminated in the cellular context. In this review, we describe the distinctive signaling roles of 2-Cys peroxiredoxins beyond their intrinsic ROS-scavenging role in relation to cancer cell death and survival.
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7
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McGuinness AJA, Sapey E. Oxidative Stress in COPD: Sources, Markers, and Potential Mechanisms. J Clin Med 2017; 6:jcm6020021. [PMID: 28212273 PMCID: PMC5332925 DOI: 10.3390/jcm6020021] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/01/2017] [Accepted: 02/05/2017] [Indexed: 12/13/2022] Open
Abstract
Markers of oxidative stress are increased in chronic obstructive pulmonary disease (COPD) and reactive oxygen species (ROS) are able to alter biological molecules, signaling pathways and antioxidant molecule function, many of which have been implicated in the pathogenesis of COPD. However, the involvement of ROS in the development and progression of COPD is not proven. Here, we discuss the sources of ROS, and the defences that have evolved to protect against their harmful effects. We address the role that ROS may have in the development and progression of COPD, as well as current therapeutic attempts at limiting the damage they cause. Evidence has indicated that the function of several key cells appears altered in COPD patients, and expression levels of important oxidant and antioxidant molecules may be abnormal. Therapeutic trials attempting to restore equilibrium to these molecules have not impacted upon all facets of disease and whilst the theory behind ROS influence in COPD appears sound, current models testing relevant pathways to tissue damage are limited. The heterogeneity seen in COPD patients presents a challenge to our understanding, and further research is essential to identify potential targets and stratified COPD patient populations where ROS therapies may be maximally efficacious.
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Affiliation(s)
| | - Elizabeth Sapey
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham B15 2TT, UK.
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8
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Liu Y, Li Q, Zhou L, Xie N, Nice EC, Zhang H, Huang C, Lei Y. Cancer drug resistance: redox resetting renders a way. Oncotarget 2016; 7:42740-42761. [PMID: 27057637 PMCID: PMC5173169 DOI: 10.18632/oncotarget.8600] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 03/28/2016] [Indexed: 02/05/2023] Open
Abstract
Disruption of redox homeostasis is a crucial factor in the development of drug resistance, which is a major problem facing current cancer treatment. Compared with normal cells, tumor cells generally exhibit higher levels of reactive oxygen species (ROS), which can promote tumor progression and development. Upon drug treatment, some tumor cells can undergo a process of 'Redox Resetting' to acquire a new redox balance with higher levels of ROS accumulation and stronger antioxidant systems. Evidence has accumulated showing that the 'Redox Resetting' enables cancer cells to become resistant to anticancer drugs by multiple mechanisms, including increased rates of drug efflux, altered drug metabolism and drug targets, activated prosurvival pathways and inefficient induction of cell death. In this article, we provide insight into the role of 'Redox Resetting' on the emergence of drug resistance that may contribute to pharmacological modulation of resistance.
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Affiliation(s)
- Yuan Liu
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, P. R. China
- Department of Neurology, The Affiliated Hospital of Hainan Medical College, Haikou, Hainan, P. R. China
| | - Qifu Li
- Department of Neurology, The Affiliated Hospital of Hainan Medical College, Haikou, Hainan, P. R. China
| | - Li Zhou
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, P. R. China
| | - Na Xie
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, P. R. China
| | - Edouard C. Nice
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Haiyuan Zhang
- Department of Neurology, The Affiliated Hospital of Hainan Medical College, Haikou, Hainan, P. R. China
| | - Canhua Huang
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, P. R. China
| | - Yunlong Lei
- Department of Biochemistry and Molecular Biology, and Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, P. R. China
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2-cys peroxiredoxins: emerging hubs determining redox dependency of Mammalian signaling networks. Int J Cell Biol 2014; 2014:715867. [PMID: 24672551 PMCID: PMC3932224 DOI: 10.1155/2014/715867] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/25/2013] [Indexed: 01/28/2023] Open
Abstract
Mammalian cells have a well-defined set of antioxidant enzymes, which includes superoxide dismutases, catalase, glutathione peroxidases, and peroxiredoxins. Peroxiredoxins are the most recently identified family of antioxidant enzymes that catalyze the reduction reaction of peroxides, such as H2O2. In particular, typical 2-Cys peroxiredoxins are the featured peroxidase enzymes that receive the electrons from NADPH by coupling with thioredoxin and thioredoxin reductase. These enzymes distribute throughout the cellular compartments and, therefore, are thought to be broad-range antioxidant defenders. However, recent evidence demonstrates that typical 2-Cys peroxiredoxins play key signal regulatory roles in the various signaling networks by interacting with or residing near a specific redox-sensitive molecule. These discoveries help reveal the redox signaling landscape in mammalian cells and may further provide a new paradigm of therapeutic approaches based on redox signaling.
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10
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Rojanathammanee L, Rakoczy S, Brown-Borg HM. Growth hormone alters the glutathione S-transferase and mitochondrial thioredoxin systems in long-living Ames dwarf mice. J Gerontol A Biol Sci Med Sci 2013; 69:1199-211. [PMID: 24285747 DOI: 10.1093/gerona/glt178] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Ames dwarf mice are deficient in growth hormone (GH), prolactin, and thyroid-stimulating hormone and live significantly longer than their wild-type (WT) siblings. The lack of GH is associated with stress resistance and increased longevity. However, the mechanism underlying GH's actions on cellular stress defense have yet to be elucidated. In this study, WT or Ames dwarf mice were treated with saline or GH (WT saline, Dwarf saline, and Dwarf GH) two times daily for 7 days. The body and liver weights of Ames dwarf mice were significantly increased after 7 days of GH administration. Mitochondrial protein levels of the glutathione S-transferase (GST) isozymes, K1 and M4 (GSTK1 and GSTM4), were significantly higher in dwarf mice (Dwarf saline) when compared with WT mice (WT saline). GH administration downregulated the expression of GSTK1 proteins in dwarf mice. We further investigated GST activity from liver lysates using different substrates. Substrate-specific GST activity (bromosulfophthalein, dichloronitrobenzene, and 4-hydrox-ynonenal) was significantly reduced in GH-treated dwarf mice. In addition, GH treatment attenuated the activity of thioredoxin and glutaredoxin in liver mitochondria of Ames mice. Importantly, GH treatment suppressed Trx2 and TrxR2 mRNA expression. These data indicate that GH has a role in stress resistance by altering the functional capacity of the GST system through the regulation of specific GST family members in long-living Ames dwarf mice. It also affects the regulation of thioredoxin and glutaredoxin, factors that regulate posttranslational modification of proteins and redox balance, thereby further influencing stress resistance.
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Affiliation(s)
- Lalida Rojanathammanee
- Department of Pharmacology, Physiology, and Therapeutics, School of Medicine and Health Sciences, University of North Dakota, Grand Forks. School of Sports Science, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Sharlene Rakoczy
- Department of Pharmacology, Physiology, and Therapeutics, School of Medicine and Health Sciences, University of North Dakota, Grand Forks
| | - Holly M Brown-Borg
- Department of Pharmacology, Physiology, and Therapeutics, School of Medicine and Health Sciences, University of North Dakota, Grand Forks.
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11
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Guttmann RP, Ghoshal S. Thiol-protease oxidation in age-related neuropathology. Free Radic Biol Med 2011; 51:282-8. [PMID: 21565267 DOI: 10.1016/j.freeradbiomed.2011.04.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 04/07/2011] [Accepted: 04/07/2011] [Indexed: 11/27/2022]
Abstract
Increased oxidative stress is a hallmark of every major neurodegenerative disease that has been studied. Numerous biomarkers of oxidative stress have been found, indicating that waves of oxidation had, at one time or another, overwhelmed antioxidant defenses, leaving behind a host of oxidized DNA, lipids, and proteins in their path. Although some level of oxidation may be beneficial, perhaps mediated by a hormetic response, the extent and types of oxidation detected in neuropathological states would suggest that oxidative stress contributes to a loss of homeostasis and cellular dysfunction. Although there are many targets of oxidants, this review emphasizes protein oxidation with a focus on an important group of redox-sensitive enzymes, the thiol-proteases. Both the direct and the indirect effects of oxidation and their potential importance in neurodegeneration are considered.
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Affiliation(s)
- Rodney P Guttmann
- Department of Gerontology, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536, USA.
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12
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Xie G, Kato H, Sasaki K, Imai R. A cold-induced thioredoxin h of rice, OsTrx23, negatively regulates kinase activities of OsMPK3 and OsMPK6 in vitro. FEBS Lett 2009; 583:2734-8. [PMID: 19665023 DOI: 10.1016/j.febslet.2009.07.057] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 07/20/2009] [Accepted: 07/29/2009] [Indexed: 12/28/2022]
Abstract
Cytosolic thioredoxins are small conserved proteins that are involved in cellular redox regulation. Here, we report that a major and cold-induced thioredoxin h of rice, OsTrx23, has an inhibitory activity on stress-activated mitogen-activated protein kinases (MAPKs), OsMPK3 and OsMPK6 in vitro. This inhibition effects were redox-dependent and did not involve stable physical interaction. The data suggested a novel mechanism for redox regulation of MAPKs in plants.
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Affiliation(s)
- Guosheng Xie
- National Agricultural Research Center for Hokkaido Region, National Agricultural and Food Research Organization, Sapporo, Japan
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13
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Oxidative modification of caspase-9 facilitates its activation via disulfide-mediated interaction with Apaf-1. Cell Res 2009; 19:449-57. [DOI: 10.1038/cr.2009.19] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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14
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Rogers D, Nylander KD, Mi Z, Hu T, Schor NF. Molecular predictors of human nervous system cancer responsiveness to enediyne chemotherapy. Cancer Chemother Pharmacol 2008; 62:699-706. [PMID: 18338171 PMCID: PMC2575071 DOI: 10.1007/s00280-008-0725-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Accepted: 02/26/2008] [Indexed: 11/25/2022]
Abstract
PURPOSE To identify and mathematically model molecular predictors of response to the enediyne chemotherapeutic agent, neocarzinostatin, in nervous system cancer cell lines. METHODS Human neuroblastoma, breast cancer, glioma, and medulloblastoma cell lines were maintained in culture. Content of caspase-3 and Bcl-2, respectively, was determined relative to actin content for each cell line by Western blotting and optical densitometry. For each cell line, sensitivity to neocarzinostatin was determined. Brain tumor cell lines were stably transfected with human Bcl-2 cDNA cloned into the pcDNA3 plasmid vector. RESULTS In human tumor cell lines of different tissue origins, sensitivity to neocarzinostatin is proportional to the product of the relative contents of Bcl-2 and caspase-3 (r (2) = 0.9; P < 0.01). Neuroblastoma and brain tumor cell lines are particularly sensitive to neocarzinostatin; the sensitivity of brain tumor lines to neocarzinostatin is enhanced by transfection with an expression construct for Bcl-2 and is proportional in transfected cells to the product of the relative contents of Bcl-2 and caspase-3 (r (2) = 0.7). CONCLUSION These studies underscore the potential of molecular profiling in identifying effective chemotherapeutic paradigms for cancer in general and tumors of the nervous system in particular.
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Affiliation(s)
- Danny Rogers
- Departments of Pediatrics, Neurology, and Neurobiology & Anatomy, University of Rochester Medical Center, Rochester, NY
| | - Karen D. Nylander
- Pediatric Center for Neuroscience, Children’s Hospital of Pittsburgh, Pittsburgh, PA
| | - Zhiping Mi
- Departments of Pediatrics, Neurology, and Neurobiology & Anatomy, University of Rochester Medical Center, Rochester, NY
| | - Tong Hu
- Departments of Pediatrics, Neurology, and Neurobiology & Anatomy, University of Rochester Medical Center, Rochester, NY
| | - Nina F. Schor
- Departments of Pediatrics, Neurology, and Neurobiology & Anatomy, University of Rochester Medical Center, Rochester, NY
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Saberi B, Shinohara M, Ybanez MD, Hanawa N, Gaarde WA, Kaplowitz N, Han D. Regulation of H(2)O(2)-induced necrosis by PKC and AMP-activated kinase signaling in primary cultured hepatocytes. Am J Physiol Cell Physiol 2008; 295:C50-63. [PMID: 18463227 DOI: 10.1152/ajpcell.90654.2007] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Recent studies have suggested that, in certain cases, necrosis, like apoptosis, may be programmed, involving the activation and inhibition of many signaling pathways. In this study, we examined whether necrosis induced by H(2)O(2) is regulated by signaling pathways in primary hepatocytes. A detailed time course revealed that H(2)O(2) treated to hepatocytes is consumed within minutes, but hepatocytes undergo necrosis several hours later. Thus, H(2)O(2) treatment induces a "lag phase" where signaling changes occur, including PKC activation, Akt (PKB) downregulation, activation of JNK, and downregulation of AMP-activated kinase (AMPK). Investigation of various inhibitors demonstrated that PKC inhibitors were effective in reducing necrosis caused by H(2)O(2) (~80%). PKC inhibitor treatment decreased PKC activity but, surprisingly, also upregulated Akt and AMPK, suggesting that various PKC isoforms negatively regulate Akt and AMPK. Akt did not appear to play a significant role in H(2)O(2)-induced necrosis, since PKC inhibitor treatment protected hepatocytes from H(2)O(2) even when Akt was inhibited. On the other hand, compound C, a selective AMPK inhibitor, abrogated the protective effect of PKC inhibitors against necrosis induced by H(2)O(2). Furthermore, AMPK activators protected against H(2)O(2)-induced necrosis, suggesting that much of the protective effect of PKC inhibition was mediated through the upregulation of AMPK. Work with PKC inhibitors suggested that atypical PKC downregulates AMPK in response to H(2)O(2). Knockdown of PKC-alpha using antisense oligonucleotides also slightly protected (~22%) against H(2)O(2). Taken together, our data demonstrate that the modulation of signaling pathways involving PKC and AMPK can alter H(2)O(2)-induced necrosis, suggesting that a signaling "program" is important in mediating H(2)O(2)-induced necrosis in primary hepatocytes.
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Affiliation(s)
- Behnam Saberi
- Research Center for Liver Diseases, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9121, USA
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16
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Xu H, Jing L, Li GS. Proteomic analysis of osteoblasts exposed to fluoride in vitro. Biol Trace Elem Res 2008; 123:91-7. [PMID: 18197394 DOI: 10.1007/s12011-007-8086-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Accepted: 12/07/2007] [Indexed: 11/30/2022]
Abstract
Proteomical analysis is defined as the characterization of the entire set of protein encoded a genome. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) are main techniques used in proteomic analysis to achieve information about protein expression profiles. Knowledge about the mechanism of skeletal fluorosis can be gained by recognizing changes in protein expression. To better understand the skeletal fluorosis process, osteoblasts isolated from calvarial of neonatal mouse were cultured and treated with 2 ppm fluoride for 72 h, and proteins of the osteoblast were profiled by 2-DE. With the analysis of Image-Master 2D analysis software, we detected a total number of 493 matching spots on 2-DE images. Among them, 28 protein spots showed twofold significant alteration (P < 0.05) in fluoride-exposed groups. Moreover, 12 proteins were identified by MALDI-TOF MS. These identified proteins in fluoride-exposed group were associated with cell proliferation, metabolism, and oxidative folding. Thus, our study provides useful information on fluoride-related changes of proteome and shows that proteomical analysis is a powerful methodology for the better understanding of skeletal fluorosis.
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Affiliation(s)
- Hui Xu
- Institute of Endemic Diseases, Jilin University, Changchun, 130021, China
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17
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Opitz I, Sigrist B, Hillinger S, Lardinois D, Stahel R, Weder W, Hopkins-Donaldson S. Taurolidine and povidone-iodine induce different types of cell death in malignant pleural mesothelioma. Lung Cancer 2007; 56:327-36. [PMID: 17383050 DOI: 10.1016/j.lungcan.2007.01.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Revised: 11/08/2006] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
Taurolidine and povidone-iodine (PVP-I) are used in every day clinical practice, taurolidine as a broad spectrum antibiotic, and PVP-I as an antiseptic. The type of cell death induced in malignant pleural mesothelioma (MPM) cell lines by these agents was compared, and their ability to sensitize to chemotherapy assessed. Both taurolidine and PVP-I inhibited MPM cell growth after 7.5min incubation, but taurolidine was more effective at later time points and was more specific towards tumour cells than PVP-I. Taurolidine induced death by caspase-dependent and independent mechanisms, whereas in contrast, PVP-I induced a necrotic phenotype that was not caspase-dependent. Interestingly, both taurolidine and PVP-I induced the production of reactive oxygen intermediates and decreased mitochondrial membrane permeability, and cell death was inhibited by the oxygen scavenger N-acetyl cysteine. Taurolidine but not PVP-I treatment resulted in p53 activation in 2/3 MPM cell lines and a decrease in the protein levels of survivin, Bcl-2 and Mcl-1. Survivin also decreased in response to PVP-I whereas Bcl-xL remained unaffected by both treatments. Targeting of Bcl-xL with siRNA sensitized MPM cells to taurolidine and taurolidine treatment sensitized MPM cells to cisplatin-induced apoptosis. In conclusion, taurolidine and PVP-I are both cytotoxic to human MPM cells at early and late time points and induce reactive oxygen intermediate production. Taurolidine induces apoptosis and necrosis, activates p53 and sensitizes cells to cisplatin, whereas PVP-I inhibits cell growth via necrosis. Both agents are promising candidates for use in local treatment within multimodality concepts for MPM.
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Affiliation(s)
- I Opitz
- Division of Thoracic Surgery, University Hospital Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
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18
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Levy M, Castillo SS, Goldkorn T. nSMase2 activation and trafficking are modulated by oxidative stress to induce apoptosis. Biochem Biophys Res Commun 2006; 344:900-5. [PMID: 16631623 PMCID: PMC4370275 DOI: 10.1016/j.bbrc.2006.04.013] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Accepted: 04/01/2006] [Indexed: 12/14/2022]
Abstract
We have previously shown that accumulation of ceramide, triggered by hydrogen peroxide (H(2)O(2)), induces apoptosis of human airway epithelial (HAE) cells. Under oxidant exposure, a lung sphingomyelinase (SMase) is activated and displays continued ceramide generation and pro-apoptotic signaling, thus leading to the pathological apoptosis that causes lung injury. In a search for a specific SMase that is modulated by oxidative stress, we recently cloned nSMase2 from monkey lung tissue and HAE cells. Here, we show that this nSMase2 is up-regulated by an oxidant (H(2)O(2)) and is inhibited by an antioxidant (glutathione (GSH)). Moreover, nSMase2 subcellular localization is governed by oxidant exposure, which leads to its preferential trafficking to the plasma membrane, where it generates ceramide and induces apoptosis. On the other hand, exposure to GSH results in nSMase2 trafficking to the nucleus, where it neither generates ceramide nor induces apoptosis.
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19
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Dumay A, Rincheval V, Trotot P, Mignotte B, Vayssière JL. The superoxide dismutase inhibitor diethyldithiocarbamate has antagonistic effects on apoptosis by triggering both cytochrome c release and caspase inhibition. Free Radic Biol Med 2006; 40:1377-90. [PMID: 16631528 DOI: 10.1016/j.freeradbiomed.2005.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Revised: 11/24/2005] [Accepted: 12/07/2005] [Indexed: 12/17/2022]
Abstract
Tumor necrosis factor-alpha (TNF-alpha) and etoposide both trigger a large and rapid production of reactive oxygen species (ROS) in HeLa cells. This occurs before translocations of the proapoptotic Bax and cytochrome c proteins, the loss of mitochondrial membrane potential (DeltaPsim), and apoptosis. We have used diethyldithiocarbamate (DDC), a well-known inhibitor of Cu, Zn superoxide dismutase to study the role of ROS in this system. We report that DDC strongly inhibits caspase activation, loss of DeltaPsim, and cell death induced by TNF-alpha or etoposide. Surprisingly, DDC does not inhibit Bax and cytochrome c translocations. On the contrary, we have observed that DDC can trigger the translocations of these proteins by itself, without altering DeltaPsim. Here, we report that DDC has at least two antagonistic apoptosis regulation functions. First, DDC triggers ROS-dependent Bax and cytochrome c translocations, which are potentially proapoptotic, and second, DDC inhibits caspase activation and activity, loss of DeltaPsim, and cell death, in a ROS-independent manner. Our results suggest an interesting model in which ROS-dependent Bax and cytochrome c translocations can be studied without interference from later apoptotic events.
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Affiliation(s)
- Anne Dumay
- Université de Versailles/St. Quentin-en-Yvelines, CNRS FRE-2445, Laboratoire de Génétique et Biologie cellulaire, Versailles, France
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20
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Marsh SA, Pat BK, Gobe GC, Coombes JS. Evidence for a non-antioxidant, dose-dependent role of alpha -lipoic acid in caspase-3 and ERK2 activation in endothelial cells. Apoptosis 2005; 10:657-65. [PMID: 15909127 DOI: 10.1007/s10495-005-1901-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Endothelial cell apoptosis contributes to atherosclerosis and may be exacerbated by oxidative stress. Results from clinical trials using antioxidant supplementation are equivocal and could be enhanced by antioxidants with additional non-antioxidant properties such as alpha -lipoic acid and alpha -tocopherol. The aim of this study was to investigate the effects of these antioxidants on cytoprotective pathways and endothelial apoptosis. Endothelial cells were incubated with alpha -lipoic acid and alpha -tocopherol, alone or in combination, prior to incubation with H(2)O(2) or staurosporine. alpha -lipoic acid pre-treatment alone increased caspase-3 activity in a dose-dependent manner. Both H(2)O(2) and staurosporine increased DNA fragmentation and caspase-3 activity and pre-treatment of cells with alpha -lipoic acid and/or alpha -tocopherol failed to prevent stress-induced apoptosis. Neither antioxidant treatments nor apoptotic inducers alone altered expressions of Bcl-2, Bax, HSP70 or pERK1/2 or pJNK. alpha -lipoic decreased pERK2 in staurosporine-treated cells in a dose-dependent manner. These findings indicate that pre-incubation with alpha -lipoic acid and alpha -tocopherol, alone or in combination, does not protect against oxidative- or non-oxidative-induced apoptosis in endothelial cells. Moreover, we have demonstrated a non-antioxidant, dose-dependent role of alpha -lipoic acid in caspase-3 and ERK2 activation. These data provide an insight and indicate caution in the use of high doses of alpha -lipoic acid as an antioxidant.
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Affiliation(s)
- S A Marsh
- School of Human Movement Studies, The University of Queensland, Brisbane, Australia
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21
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Silva RD, Sotoca R, Johansson B, Ludovico P, Sansonetty F, Silva MT, Peinado JM, Côrte-Real M. Hyperosmotic stress induces metacaspase- and mitochondria-dependent apoptosis inSaccharomyces cerevisiae. Mol Microbiol 2005; 58:824-34. [PMID: 16238630 DOI: 10.1111/j.1365-2958.2005.04868.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
During the last years, several reports described an apoptosis-like programmed cell death process in yeast in response to different environmental aggressions. Here, evidence is presented that hyperosmotic stress caused by high glucose or sorbitol concentrations in culture medium induces in Saccharomyces cerevisiae a cell death process accompanied by morphological and biochemical indicators of apoptotic programmed cell death, namely chromatin condensation along the nuclear envelope, mitochondrial swelling and reduction of cristae number, production of reactive oxygen species and DNA strand breaks, with maintenance of plasma membrane integrity. Disruption of AIF1 had no effect on cell survival, but lack of Yca1p drastically reduced metacaspase activation and decreased cell death indicating that this death process was associated to activation of this protease. Supporting the involvement of mitochondria and cytochrome c in caspase activation, the mutant strains cyc1Deltacyc7Delta and cyc3Delta, both lacking mature cytochrome c, displayed a decrease in caspase activation associated to increased cell survival when exposed to hyperosmotic stress. These findings indicate that hyperosmotic stress triggers S. cerevisiae into an apoptosis-like programmed cell death that is mediated by a caspase-dependent mitochondrial pathway partially dependent on cytochrome c.
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Affiliation(s)
- Rui D Silva
- Departamento de Biologia-Centro de Biologia Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
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22
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Mi Z, Hong B, Mirnics ZK, Tyurina YY, Kagan VE, Liang Y, Schor NF. Bcl-2-mediated potentiation of neocarzinostatin-induced apoptosis: requirement for caspase-3, sulfhydryl groups, and cleavable Bcl-2. Cancer Chemother Pharmacol 2005; 57:357-67. [PMID: 16001169 DOI: 10.1007/s00280-005-0054-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2005] [Accepted: 05/02/2005] [Indexed: 10/25/2022]
Abstract
Overexpression of antiapoptotic Bcl-2 family members is thought to contribute to chemotherapeutic resistance of neural crest tumors. Paradoxical potentiation by Bcl-2 of apoptosis induced by the antineoplastic prodrug, neocarzinostatin (NCS), has been observed in PC12 pheochromocytoma cells. Prior studies have indicated that the cleavage of Bcl-2 to its proapoptotic counterpart mediated by caspase-3 is responsible for this potentiation of apoptosis. This has led to the hypothesis that induction of caspase-3 expression in bcl-2-transfected, caspase-3-deficient MCF-7 cells, will result in Bcl-2 cleavage and Bcl-2-dependent potentiation of NCS-induced apoptosis. These studies have further led to the hypothesis that both cleavable Bcl-2 and sulfhydryl groups are required for the activity of caspase-3 in this regard. As hypothesized, co-transfection of bcl-2-transfected MCF-7 cells with a caspase-3 expression construct results in cleavage of Bcl-2 and potentiation of dose-dependent, NCS-mediated cell death. Furthermore, PC12 cells transfected with an expression construct for cleavage-resistant Bcl-2 demonstrated attenuated potentiation of apoptosis relative to their counterparts transfected with wild-type bcl-2. Finally, irreversible oxidative titration of sulfhydryl groups resulted in concentration-dependent attenuation of apoptosis in PC12 cells, along with prevention of caspase-3 activation and Bcl-2 cleavage. These results definitively demonstrate the requirement for caspase-3, cleavable Bcl-2, and available sulfhydryl groups (separate from those required for NCS activation) in potentiation of NCS-induced apoptosis by Bcl-2.
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Affiliation(s)
- Zhiping Mi
- Division of Child Neurology, Pediatric Center for Neuroscience, Children's Hospital of Pittsburgh of UPMC, PA 15213, USA
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23
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Nappi AJ, Christensen BM. Melanogenesis and associated cytotoxic reactions: applications to insect innate immunity. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 35:443-459. [PMID: 15804578 DOI: 10.1016/j.ibmb.2005.01.014] [Citation(s) in RCA: 377] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Revised: 01/05/2005] [Accepted: 01/07/2005] [Indexed: 05/24/2023]
Abstract
Insects transmit the causative agents for such debilitating diseases as malaria, lymphatic filariases, sleeping sickness, Chagas' disease, leishmaniasis, river blindness, Dengue, and yellow fever. The persistence of these diseases provides testimony to the genetic capacity of parasites to evolve strategies that ensure their successful development in two genetically diverse host species: insects and mammals. Current efforts to address the problems posed by insect-borne diseases benefit from a growing understanding of insect and mammalian immunity. Of considerable interest are recent genomic investigations that show several similarities in the innate immune effector responses and associated regulatory mechanisms manifested by insects and mammals. One notable exception, however, is the nearly universal presence of a brown-black pigment accompanying cellular innate immunity in insects. This response, which is unique to arthropods and certain other invertebrates, has focused attention on the elements involved in pigment synthesis as causing or contributing to the death of the parasite, and has even prompted speculation that the enzyme cascade mediating melanogenesis constitutes an ill-defined recognition mechanism. Experimental evidence defining the role of melanin and its precursors in insect innate immunity is severely lacking. A great deal of what is known about melanogenesis comes from studies of the process occurring in mammalian systems, where the pigment is synthesized by such diverse cells as those comprising portions of the skin, hair, inner ear, brain, and retinal epithelium. Fortunately, many of the components in the metabolic pathways leading to the formation of melanin have been found to be common to both insects and mammals. This review examines some of the factors that influence enzyme-mediated melanogenic responses, and how these responses likely contribute to blood cell-mediated, target-specific cytotoxicity in immune challenged insects.
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Affiliation(s)
- A J Nappi
- Department of Animal Health and Biomedical Sciences, University of Wisconsin-Madison, WI 53706, USA.
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24
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Clément MV, Sivarajah S, Pervaiz S. Production of intracellular superoxide mediates dithiothreitol-dependent inhibition of apoptotic cell death. Antioxid Redox Signal 2005; 7:456-64. [PMID: 15706093 DOI: 10.1089/ars.2005.7.456] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Apoptotic cell death proceeds from the activation of cysteine proteinases called caspases. As full enzymatic activity of caspases requires reduction of cysteine residues in and around the catalytic site of the proteases, cysteine- reducing agents such as dithiothreitol (DTT) are expected to facilitate caspase activity upon induction of apoptosis. However, DTT has been shown to efficiently protect cells from apoptosis. The mechanism involved in DTT-mediated inhibition of apoptosis has been attributed to its antioxidant activity. Interestingly, under physiological conditions, thiol-mediated antioxidant reaction has also been shown to result in intracellular generation of superoxide (O(2) (.-)). In line with our earlier findings implicating a slight prooxidant state in resistance to apoptosis, we set out to investigate if the death-inhibitory activity of DTT could be mediated by intracellular O2 (.-). Our results show that incubation of human melanoma cell line M14TF or human bladder carcinoma cell line T24 with DTT induced an increase in intracellular O2 (.-) with concomitant inhibition of apoptosis triggered by CD95 signaling, staurosporine, or hydrogen peroxide. Moreover, preincubation of either cells with Tiron, a specific O2 (.-) scavenger, reverted DTT-induced inhibition of apoptosis. These results show that the apoptosis-inhibitory activity of DTT may not be due to its antioxidant property, but instead linked to its ability to induce an increase in intracellular O2 (.-) level.
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Affiliation(s)
- Marie-Véronique Clément
- Department of Biochemistry, National University of Singapore, 8 Medical Drive, Singapore 117-597.
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25
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Ibuki Y, Goto R. Dysregulation of apoptosis by benzene metabolites and their relationships with carcinogenesis. Biochim Biophys Acta Mol Basis Dis 2004; 1690:11-21. [PMID: 15337166 DOI: 10.1016/j.bbadis.2004.04.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Revised: 03/30/2004] [Accepted: 04/21/2004] [Indexed: 01/29/2023]
Abstract
Benzene is a widely recognized human carcinogen, the effect of which is attributed to the production of reactive oxygen species (ROS) from its metabolites. Although there have been many reports on the relationship between DNA damage induced by benzene metabolites and carcinogenesis, only a report approached the subject by examining the benzene-induced dysregulation of apoptosis. Inhibition of apoptosis, aberrantly prolonging cell survival, may contribute to cancer by facilitating the insurgence of mutations and by creating a permissive environment for genetic instability. In this study, we examined the mechanism of antiapoptotic effects by benzene metabolites, p-benzoquinone (BQ) and hydroquinone (HQ), and their relationships with carcinogenesis. BQ and HQ inhibited the apoptotic death of NIH3T3 cells induced by both serum starvation and lack of an extracellular matrix (ECM). An antioxidant agent, N-acetylcysteine, significantly inhibited the antiapoptotic effects induced by benzene metabolites, indicating that the effects were mainly due to the production of ROS. Furthermore, BQ and HQ inhibited the in vitro caspase-3 activation, suggesting that the inhibition of caspase-3 activation due to ROS produced by BQ- and HQ-treatment was related to the suppression of apoptosis. The cells that escaped apoptosis could survive with the addition of serum and attachment to the ECM. Levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine were higher in the cells which survived after BQ- and HQ-treatment than in the normal cells. Furthermore, the cells treated with BQ and HQ showed greater proliferation than normal cells under low-serum conditions and anchorage-independent growth in soft agar. These findings suggested that benzene metabolites induced dysregulation of apoptosis due to caspase-3 inhibition, which contributes to carcinogenesis.
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Affiliation(s)
- Yuko Ibuki
- Laboratory of Radiation Biology, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan.
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26
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Katoh I, Tomimori Y, Ikawa Y, Kurata SI. Dimerization and Processing of Procaspase-9 by Redox Stress in Mitochondria. J Biol Chem 2004; 279:15515-23. [PMID: 14747474 DOI: 10.1074/jbc.m311819200] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We studied the mechanism of intra-mitochondrial death initiator caspase-9 activation by a redox response, in which hydrogen peroxide (H(2)O(2)) caused a subtle decrease in the inner membrane potential (Deltapsim) with little evidence of cytochrome c release. Initiation of the intra-mitochondrial autocleavage of procaspase-9 preceded the onset of caspase cascade induction in the cytosol. Purified mitochondria demonstrated procaspase-9 processing and releasing abilities when exposed to H(2)O(2). Bcl-2 overexpression caused accumulation of the active form caspase-9 in the mitochondria, rendering the cells resistant to the redox stress. Intriguingly, disulfide-bonded dimers of autoprocessed caspase-9 were generated in the mitochondria in the pre-apoptotic phase. Using a substrate-analog inhibitor, dimer formation of procaspase-9 was also detectable inside the mitochondria. Furthermore, thiol reductant thioredoxin blocked the caspase-9 activation step and the cell death induction. Thus, redox stress-responsive thiol-disulfide converting reactions in the mitochondrion seemed to mediate procaspase-9 assembly that allows autoprocessing. This study offers an explanation for the recent observation that Apaf-1-null cells can execute apoptosis, which can be blocked by Bcl-2, and supports the proposition that the cytochrome c-Apaf-1-procaspase-9 complex functions in the caspase amplification rather than in its initiation.
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Affiliation(s)
- Iyoko Katoh
- Ikawa Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 350-0198, Japan.
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27
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Rosati E, Sabatini R, Ayroldi E, Tabilio A, Bartoli A, Bruscoli S, Simoncelli C, Rossi R, Marconi P. Apoptosis of human primary B lymphocytes is inhibited by N-acetyl-L-cysteine. J Leukoc Biol 2004; 76:152-61. [PMID: 14726501 DOI: 10.1189/jlb.0403148] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Thiols are important molecules to control apoptosis. This study examined the effect of N-acetyl-L-cysteine (NAC) on in vitro spontaneous apoptosis of human tonsillar B lymphocytes (TBL). Results show that NAC inhibits TBL apoptosis and maintains their survival in vitro. The antiapoptotic action of NAC is progressively reduced when its addition to culture is delayed, is reversible, and is not blocked by cycloheximide. The antiapoptotic activity of NAC is associated with its ability to inhibit caspase-3 and -7 proteolytic processing, DNA-fragmentation factor 45 cleavage, and DNA fragmentation. Furthermore, NAC inhibits BID cleavage and cytochrome c release from mitochondria and increases the expression of Bcl-2 and Bcl(XL) survival proteins. However, it has no effect on caspase-9 cleavage and increases that of caspase-8 and poly(adenosine 5'-diphosphate-ribose)polymerase. We conclude that NAC-induced inhibition of TBL apoptosis is associated with inhibition of caspase-3 and -7 processing and is accompanied by changes in several regulatory components of the apoptotic process. These results pose the question of whether microenvironment thiols may in part contribute to in vivo B cell survival.
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Affiliation(s)
- Emanuela Rosati
- General Pathology and Immunology Section, University of Perugia, Via Brunamonti, General Hospital-Monteluce 06100 Perugia, Italy
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28
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Jeong W, Chang TS, Boja ES, Fales HM, Rhee SG. Roles of TRP14, a thioredoxin-related protein in tumor necrosis factor-alpha signaling pathways. J Biol Chem 2003; 279:3151-9. [PMID: 14607843 DOI: 10.1074/jbc.m307959200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The possible roles of a 14-kDa human thioredoxin (Trx)-related protein (TRP14) in TNF-alpha signaling were studied in comparison with those of Trx1 by RNA interference in HeLa cells. Depletion of TRP14 augmented the TNF-alpha-induced phosphorylation and degradation of I kappa B alpha as well as the consequent activation of NF-kappa B to a greater extent than did Trx1 depletion. Deficiency of TRP14 or Trx1 enhanced TNF-alpha-induced activation of caspases and subsequent apoptosis by a similar extent. The TNF-alpha-induced activation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs), however, was promoted by depletion of TRP14 but not by that of Trx1. Unlike Trx1, TRP14 neither associated with nor inhibited the kinase activity of apoptosis signal-regulating kinase-1 (ASK1), an upstream activator of JNK and p38. In combination with the results in the accompanying paper that TRP14 did not reduce the known substrates of Trx1, these results suggest that TRP14 modulates TNF-alpha signaling pathways, provably by interacting with proteins distinct from the targets of Trx1. In an effort to identify target proteins of TRP14, a mutant of TRP14, in which the active site cysteine (Cys(46)) was substituted with serine, was shown to form a disulfide-linked complex with LC8 cytoplasmic dynein light chain. The complex was detected in HeLa cells treated with H(2)O(2) or TNF-alpha but not in untreated cells, suggesting that LC8 cytoplasmic dynein light chain is a possible substrate of TRP14.
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Affiliation(s)
- Woojin Jeong
- Laboratory of Cell Signaling, National Heart, Lung and Bllod Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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29
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Kwon YW, Masutani H, Nakamura H, Ishii Y, Yodoi J. Redox regulation of cell growth and cell death. Biol Chem 2003; 384:991-6. [PMID: 12956415 DOI: 10.1515/bc.2003.111] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Oxidative stress evokes various cellular events, including activation of transcription factors, apoptosis, and cell cycle arrest. Accumulating evidence shows that reduction/oxidation (redox) plays an important role in the regulation of apoptosis and cell cycle arrest elicited by oxidative stress. Cellular redox is controlled by the thioredoxin (TRX) and glutathione (GSH) systems. TRX and GSH systems regulate cell growth and cell death by the activation of transcription factors, the sensitivity of cells to cytokines and growth factors, and the components of the apoptosis pathways. This brief review describes the current knowledge on the redox regulation of cell growth and apoptosis.
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Affiliation(s)
- Yong-Won Kwon
- Institute for Virus Research, Kyoto University, 53 Shogoin, Kawahara-cho, Sakyo, Kyoto 606-8507, Japan
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Ibuki Y, Goto R. The antiapoptotic effect of low-dose UVB irradiation in NIH3T3 cells involves caspase inhibitions. Photochem Photobiol 2003. [PMID: 12685655 DOI: 10.1562/0031-8655(2003)0770276taeold2.0.co2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
UVB irradiation is a well-known apoptosis induction factor. However, we have previously found that low doses of UVB irradiation inhibited apoptosis induced by both serum starvation and lack of extracellular matrix, involving a significant inhibition of caspase-3/7 activation. In this study, we report on the relationship between the UVB-induced anti-apoptotic effect and caspase-3/7 inhibition by reactive oxygen species (ROS). The UVB-induced antiapoptotic effect was partially prevented by an antioxidant agent, N-acetylcysteine. A ROS-generating agent, menadione and a pro-oxidant agent, H2O2 also showed an effect that was similar to the UVB-induced antiapoptotic effect, indicating that ROS contributed to the antiapoptotic effect. UVB irradiation significantly suppressed caspase-3/7 activation, which was caused by the inhibition of proteolysis and not by the inhibition of enzymatic activity itself. The prevention of proteolysis was also confirmed by both the following results: one is the inhibition of in vitro caspase-3/7 and -9 activation in cell lysates exposed to UVB in the presence of cytochrome c and dATP, which was caused by the production of ROS, and the other is the inhibition of in vitro caspase-3/7 activation in the presence of active caspase-9. These results showed that the inhibition of the caspase cascade downstream mitochondria by ROS production, leading to a significant inhibition of caspase-3/7 activation, was one of the causes of the antiapoptotic effect by small doses of UVB irradiation.
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Affiliation(s)
- Yuko Ibuki
- Laboratory of Radiation Biology, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada, Shizuoka-shi, Japan.
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31
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Chen Q, Crosby M, Almasan A. Redox Regulation of Apoptosis before and after Cytochrome C Release. ACTA ACUST UNITED AC 2003; 7:1-9. [PMID: 16467897 PMCID: PMC1343461 DOI: 10.1080/12265071.2003.9647675] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Programmed cell death, or apoptosis, is one of the most studied areas of modern biology. Apoptosis is a genetically regulated process, which plays an essential role in the development and homeostasis of higher organisms. Mitochondria, known to play a central role in regulating cellular metabolism, was found to be critical for regulating apoptosis induced under both physiological and pathological conditions. Mitochondria are a major source of reactive oxygen species (ROS) but they can also serve as its target during the apoptosis process. Release of apoptogenic factors from mitochondria, the best known of which is cytochrome c, leads to assembly of a large apoptosis-inducing complex called the apoptosome. Cysteine proteases (called caspases) are recruited to this complex and, following their activation by proteolytic cleavage, activate other caspases, which in turn target for specific cleavage a large number of cellular proteins. The redox regulation of apoptosis during and after cytochrome c release is an area of intense investigation. This review summarizes what is known about the biological role of ROS and its targets in apoptosis with an emphasis on its intricate connections to mitochondria and the basic components of cell death.
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Affiliation(s)
- Quan Chen
- *To whom correspondence should be addressed, Tel: 86-10-6252-9232, Fax: +6256-5689, E-mail:
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32
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Fonfría E, Daré E, Benelli M, Suñol C, Ceccatelli S. Translocation of apoptosis-inducing factor in cerebellar granule cells exposed to neurotoxic agents inducing oxidative stress. Eur J Neurosci 2002; 16:2013-6. [PMID: 12453066 DOI: 10.1046/j.1460-9568.2002.02269.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have previously shown that the neurotoxic compounds colchicine, methylmercury (MeHg) and hydrogen peroxide (H2O2) cause apoptosis in primary cultures of cerebellar granule cells (CGC), characterized by nuclear condensation and high-molecular weight DNA fragmentation. However, only colchicine triggers the activation of caspases, suggesting that factors other than caspase-activated DNase (CAD) are responsible for DNA cleavage in the other two models. Here we report that the two agents that cause oxidative stress, MeHg (1 micro m) and H2O2 (50 micro m), induce translocation of apoptosis-inducing factor (AIF) from the mitochondria to the nucleus in CGC. Our data suggest that, in absence of caspase activity, AIF translocation could be a key event leading to chromatin condensation and DNA degradation in CGC exposed to MeHg and H2O2.
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Affiliation(s)
- E Fonfría
- Institute of Environmental Medicine, Division of Toxicology and Neurotoxicology, Karolinska Institutet, S-171 77 Stockholm, Sweden
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33
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Priault M, Bessoule JJ, Grelaud-Coq A, Camougrand N, Manon S. Bax-induced cell death in yeast depends on mitochondrial lipid oxidation. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:5440-50. [PMID: 12423342 DOI: 10.1046/j.1432-1033.2002.03234.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The oxidant function of pro-apoptotic protein Bax was investigated through heterologous expression in yeast. Direct measurements of fatty acid content show that Bax-expression induces oxidation of mitochondrial lipids. This effect is prevented by the coexpression of Bcl-xL. The oxidation actually could be followed on isolated mitochondria as respiration-induced peroxidation of polyunsaturated cis-parinaric acid and on whole cells as the increase in the amount of thiobarbituric acid-reactive products. Treatments that increase the unsaturation ratio of lipids, making them more sensitive to oxidation, increase kinetics of Bax-induced death. Conversely, inhibitors of lipid oxidation and treatments that decrease the unsaturation ratio of fatty acids decrease kinetics of Bax-induced death. Taken together, these results show that Bax-induced mitochondrial lipid oxidation is relevant to Bax-induced cell death. Conversely, lipid oxidation is poorly related to the massive Bax-induced superoxide and hydrogen peroxide accumulation, which occurs at the same time, as chemical or enzymatic scavenging of ROS does not prevent lipid oxidation nor has any effects on kinetics of Bax-induced cell death. Whatever the origin of mitochondrial lipid oxidation, these data show that it represents a major step in the cascade of events leading to Bax-induced cell death. These results are discussed in the light of the role of lipid oxidation both in mammalian apoptosis and in other forms of cell death in other organisms.
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Affiliation(s)
- Muriel Priault
- UMR5095 C.N.R.S./Université de Bordeaux 2, Bordeaux, France; UMR5544 C.N.R.S./Université de Bordeaux 2, Bordeaux, France
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34
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Abstract
The role of regulation of nitric oxide synthase (NOS) activity in mitigating oxidative stress in neonatal lungs and contributing to pulmonary vasodilation at birth is still unclear. Furthermore, it is known that, depending on interactions between the individual components of the mitogen-activated protein kinase (MAPK) signaling cascades, many biological consequences, including apoptosis, are initiated. Although the importance of nitric oxide (NO) in apoptosis is controversial and likely depends on NO concentrations and cell types, this highly reactive free radical can activate the p38 MAPK signal cascade. Recent studies have suggested that thioredoxin may play an important role as an effector for some of these functions. Thioredoxin is a major redox protein for many enzymes/transcription factors and is involved in cellular functions, such as viability, activation, and proliferation. In addition to its redox regulation, thioredoxin binds directly to the apoptosis signal-regulating kinase 1 (ASK1), thus inhibiting the activation of stress-induced MAPK signaling cascades that lead to apoptosis. Furthermore, NO produced from newly induced neuronal NOS was reported to induce expression of thioredoxin and several other genes for preconditioning-induced neuroprotection. Moreover, although exposure of endothelial cells to NO decreases NOS activity, this inhibition was shown to be reversed by thioredoxin. Finally, the correlation of expression of thioredoxin with endothelial NOS activity seems to suggest an important role played by this protein in perinatal changes of pulmonary artery functions. Therefore, thioredoxin may participate in the regulation of NOS activity and be involved in NO functions via multiple mechanisms.
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Affiliation(s)
- Li-En Shao
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
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35
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Hampton MB, Stamenkovic I, Winterbourn CC. Interaction with substrate sensitises caspase-3 to inactivation by hydrogen peroxide. FEBS Lett 2002; 517:229-32. [PMID: 12062443 DOI: 10.1016/s0014-5793(02)02629-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Caspases have an active site cysteine whose oxidation blocks catalytic activity. Caspase activity, measured in lysates of apoptotic cells, was inhibited by H2O2 with an IC50 of 7 microM. Recombinant caspase-3 was directly inhibited by H2O2, with an estimated second-order rate constant of 750 M-1 s-1. These values were determined when H2O2 was added while the caspases were cleaving a peptide substrate. There was a 40-fold decrease in sensitivity to inactivation if the substrate was absent at the time of H2O2 addition. These results rationalise conflicting reports of the sensitivity of caspase-3 to H2O2, and identify a novel mechanism for sensitising a thiol enzyme to oxidative inactivation.
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Affiliation(s)
- Mark B Hampton
- Free Radical Research Group, Christchurch School of Medicine and Health Sciences, Christchurch, New Zealand.
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36
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Armstrong JS, Steinauer KK, Hornung B, Irish JM, Lecane P, Birrell GW, Peehl DM, Knox SJ. Role of glutathione depletion and reactive oxygen species generation in apoptotic signaling in a human B lymphoma cell line. Cell Death Differ 2002; 9:252-63. [PMID: 11859408 DOI: 10.1038/sj.cdd.4400959] [Citation(s) in RCA: 343] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2001] [Revised: 08/24/2001] [Accepted: 09/09/2001] [Indexed: 12/13/2022] Open
Abstract
The primary objective of this study was to determine the sequence of biochemical signaling events that occur after modulation of the cellular redox state in the B cell lymphoma line, PW, with emphasis on the role of mitochondrial signaling. L-Buthionine sulphoximine (BSO), which inhibits gamma glutamyl cysteine synthetase (gammaGCS), was used to modulate the cellular redox status. The sequence and role of mitochondrial events and downstream apoptotic signals and mediators was studied. After BSO treatment, there was an early decline in cellular glutathione (GSH), followed by an increase in reactive oxygen species (ROS) production, which induced a variety of apoptotic signals (detectable at different time points) in the absence of any external apoptotic stimuli. The sequence of biochemical events accompanying apoptosis included a 95% decrease in total GSH and a partial (25%) preservation of mitochondrial GSH, without a significant increase in ROS production at 24h. Early activation and nuclear translocation of the nuclear factor kappa B subunit Rel A was observed at approximately 3h after BSO treatment. Cytochrome c release into the cytosol was also seen after 24h of BSO treatment. p53 protein expression was unchanged after redox modulation for up to 72 h, and p21waf1 independent loss of cellular proliferation was observed. Surprisingly, a truncated form of p53 was expressed in a time-dependent manner, beginning at 24h after BSO incubation. Irreversible commitment to apoptosis occurred between 48 and 72 h after BSO treatment when mitochondrial GSH was depleted, and there was an increase in ROS production. Procaspase 3 protein levels showed a time-dependent reduction following incubation with BSO, notably after 48 h, that corresponded with increasing ROS levels. At 96 h, caspase 3 cleavage products were detectable. The pan-caspase inhibitor zVADfmk, partially blocked the induction of apoptosis at 48 h, and was ineffective after 72 h. PW cells could be rescued from apoptosis by removing them from BSO after up to 48, but not 72 h incubation with BSO. Mitochondrial transmembrane potential (DeltaPsi(m)) remained intact in most of the cells during the 72 h observation period, indicating that DeltaPsi(m) dissipation is not an early signal for the induction of redox dependent apoptosis in PW cells. These data suggest that a decrease in GSH alone can act as a potent early activator of apoptotic signaling. Increased ROS production following mitochondrial GSH depletion, represents a crucial event, which irreversibly commits PW cells to apoptosis.
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Affiliation(s)
- J S Armstrong
- Department of Radiation Oncology, Stanford University, Stanford, California, CA 94305-5105, USA
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37
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Hentze H, Schmitz I, Latta M, Krueger A, Krammer PH, Wendel A. Glutathione dependence of caspase-8 activation at the death-inducing signaling complex. J Biol Chem 2002; 277:5588-95. [PMID: 11734564 DOI: 10.1074/jbc.m110766200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Apoptosis triggered by the death receptor CD95 (APO-1 or Fas) is pivotal for the homeostasis of the immune system. We investigated differential effects of glutathione depletion on CD95-triggered apoptosis in T and B cell lines as well as the glutathione dependence of caspase-8 activation. In B lymphoblastoid SKW6.4 cells, CD95-mediated apoptosis was prevented upstream of caspase-8 activation and caspase-3-like activity after acute glutathione depletion by diethyl maleate or cis-chloro-dinitrobenzene. Immunoprecipitation of the death-inducing signaling complex (DISC) revealed that the DISC was still formed in the glutathione-depleted state. The first cleavage step of procaspase-8 activation at the DISC, however, was inhibited. Accordingly, under cell-free conditions, radiolabeled procaspase-8 was processed at the immunoprecipitated DISC only after the addition of exogenous dithiothreitol or reduced glutathione. We also observed suppression of CD95-mediated apoptosis in glutathione-depleted CEM and H9 cells. Notably, Jurkat cells still died upon CD95 engagement under this condition, displaying incomplete nuclear fragmentation and a partial switch to necrosis; this may be explained by reduced cytochrome c/dATP-mediated caspase activation observed in cytosol from glutathione-depleted Jurkat cytosol. Our data indicate that the activation of caspase-8 at the DISC and hence CD95-mediated apoptosis induction shows a cell-specific requirement for intracellular glutathione.
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Affiliation(s)
- Hannes Hentze
- Biochemical Pharmacology, Department of Biology, University of Konstanz, D-78457 Konstanz, Germany.
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38
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Liang Y, Nylander KD, Yan C, Schor NF. Role of caspase 3-dependent Bcl-2 cleavage in potentiation of apoptosis by Bcl-2. Mol Pharmacol 2002; 61:142-9. [PMID: 11752215 DOI: 10.1124/mol.61.1.142] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous studies from our laboratory have demonstrated that Bcl-2 has a proapoptotic effect on neocarzinostatin (NCS)-treated PC12 pheochromocytoma cells. In the present study, we examine the mechanisms of this effect and demonstrate its relevance for the in vivo situation. Four hours after NCS treatment, a 23-kDa cleavage product of Bcl-2 was detected in whole cell lysates of bcl-2-transfected PC12 cells. In contrast, bcl-2 transfection protected PC12 cells from cisplatin-induced apoptosis, and cisplatin treatment did not result in Bcl-2 cleavage. Similarly, Bcl-2 cleavage did not occur and Bcl-2-mediated protection from, rather than potentiation of apoptosis was observed after NCS treatment of MCF-7 breast cancer cells. The caspase 3-specific inhibitor Ac-DEVD-CHO prevented Bcl-2 cleavage and attenuated NCS-induced apoptosis in bcl-2-transfected PC12 cells, whereas it had no effect on NCS-induced apoptosis in mock-transfected PC12 cells. Furthermore, MCF-7 cells do not express caspase 3, a finding in concert with the lack of Bcl-2 cleavage in this line. In in vivo experiments, xenografts of bcl-2-transfected PC12 cells were more susceptible to NCS toxicity than were xenografts of mock-transfected PC12 cells. Caspase 3-mediated Bcl-2 cleavage therefore plays an important role in the potentiation by Bcl-2 of NCS-induced apoptosis.
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Affiliation(s)
- Ye Liang
- The Pediatric Center for Neuroscience, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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39
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Daré E, Gorman AM, Ahlbom E, Götz M, Momoi T, Ceccatelli S. Apoptotic morphology does not always require caspase activity in rat cerebellar granule neurons. Neurotox Res 2001; 3:501-14. [PMID: 14715461 DOI: 10.1007/bf03033206] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The death of a cell via apoptosis is characterized by morphological changes including cell shrinkage and nuclear condensation. Intracellularly, proteases, including caspases, are activated. In the present article we have compared the ability of three different neurotoxic agents to induce caspase activity in cerebellar granule cells (CGC). These compounds are the microtubule-disrupting agent colchicine and the oxidative stress-inducing agents hydrogen peroxide and methylmercury (MeHg). We have previously shown that each of these agents causes nuclear changes that are consistent with apoptosis, i.e., induction of chromatin condensation and DNA cleavage into fragments of regular size (700, 300 and 50 kbp). However, only colchicine causes a large increase in caspase activity, as monitored by the ability of whole cell extracts to cleave the synthetic caspase substrate DEVD-MCA. In contrast, MeHg and hydrogen peroxide do not induce any significant increase of DEVDase activity as compared to control cells. Immunocytochemistry confirms that active caspase-3 is abundant only in colchicine-exposed cells. In agreement with these findings, the pan-caspase inhibitor, z-VAD-fmk, is efficient in protecting CGC against colchicine, but not against hydrogen peroxide or MeHg. These data suggest that in CGC the activation of caspases is not always required to induce morphological changes and pattern of DNA fragmentation consistent with apoptosis.
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Affiliation(s)
- E Daré
- Institute of Environmental Medicine, Division of Toxicology and Neurotoxicology, Karolinska Institutet, S-171 77 Stockholm, Sweden
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40
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Didier C, Kerblat I, Drouet C, Favier A, Béani JC, Richard MJ. Induction of thioredoxin by ultraviolet-A radiation prevents oxidative-mediated cell death in human skin fibroblasts. Free Radic Biol Med 2001; 31:585-98. [PMID: 11522443 DOI: 10.1016/s0891-5849(01)00617-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The present study analyzes the expression of the thioredoxin/thioredoxin reductase (Trx/TR) system in UVA-irradiated human skin fibroblasts. Irradiation increases the intracellular level of Trx and a time-dependent increase of Trx mRNA is observed. Our data indicate that Trx translocates from the cytoplasm to the nucleus. In addition, UV exposure results in an increase in TR synthesis. In order to evaluate the function of Trx/TR system, we investigated the antioxidant role of Trx in transient transfected cells. The ROS accumulation in UVA irradiated cells was assessed using flow cytometry. A 3-fold decrease in ROS production was observed in transiently transfected fibroblasts. These results indicate that Trx acts as an antioxidant protein in UVA irradiated fibroblasts. As ROS are inducers of cell death, this raises the question as to whether Trx is able to protect cells from apoptosis and/or necrosis induced by UVA. Six hours after UVA-irradiation, 29.92% of cells were annexin-V positive. This population was significantly reduced in Trx-transfected cells (8.58%). Moreover, this work demonstrates that Trx prevents the loss of the membrane potential of the mitochondria, the depletion of cellular ATP content, and the loss of cell viability induced by irradiation.
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Affiliation(s)
- C Didier
- LBSO/LCR7 n8 Université Joseph Fourier, Grenoble, France
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41
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Abstract
Caspases are critical mediators of apoptotic cell death. All members of the caspase family contain the sequence QACXG which contains the active site cysteine. The putative active site of caspase 3 contains a cysteine residue that is subject to redox control. Both thioredoxin and glutathione have been shown to be required for caspase-3 activity to induce apoptosis. The regulation of inducible caspase 3 activity by oxidation-reduction (redox) dependent mechanisms is reviewed. Up until a few years ago, reactive oxygen species (ROS) research mostly focussed on oxidative damage and ROS were thought to be a key trigger for cell death. This view has been refined, leading to the understanding that the biological function of ROS is determined by numerous variables such as concentration, chemical type and cellular localization. For example, ROS and reactive nitrogen species may intercept inducible cell death under certain circumstances via the redox regulation of inducible caspase activity and/or by depleting cellular energy stores. Likewise, death of unwanted diseased or degenerative cells may be facilitated by pharmacologically enhancing the thiol status of such cells using redox-active α-lipoic acid.
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Affiliation(s)
- C K Sen
- Laboratory of Molecular Medicine, Department of Surgery, 512 Heart and Lung Research Institute, The Ohio State University Medical Center, 473 W. 12th Avenue, Columbus, OH 43210, USA
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42
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Hentze H, Schwoebel F, Lund S, Keel M, Ertel W, Wendel A, Jäättelä M, Leist M, Kehl M. In Vivo and in Vitro Evidence for Extracellular Caspase Activity Released from Apoptotic Cells. Biochem Biophys Res Commun 2001; 283:1111-7. [PMID: 11355887 DOI: 10.1006/bbrc.2001.4918] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
While caspases play an established role as intracellular executors of apoptosis, little is known about extracellular activities of this ubiquitously expressed family of proteases. We demonstrate here that recombinant caspase-3 retained enzymatic activity in various extracellular fluids. Experiments with cell lines, primary cells, and mice with fulminant CD95-triggered hepatitis showed that significant amounts of DEVD-aminofluoromethylcoumarine-cleaving activity, indicative of active effector caspases, were released into the medium/plasma during apoptosis. Furthermore, caspase activities were detected in liquor samples from human head trauma patients. These findings warrant closer investigation of DEVDase activity as a diagnostic marker, and of potential extracellular substrates for caspases.
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Affiliation(s)
- H Hentze
- Faculty of Biology, University of Konstanz, Konstanz, 78457, Germany
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43
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Chrestensen CA, Starke DW, Mieyal JJ. Acute cadmium exposure inactivates thioltransferase (Glutaredoxin), inhibits intracellular reduction of protein-glutathionyl-mixed disulfides, and initiates apoptosis. J Biol Chem 2000; 275:26556-65. [PMID: 10854441 DOI: 10.1074/jbc.m004097200] [Citation(s) in RCA: 234] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Oxidative stress broadly impacts cells, initiating regulatory pathways as well as apoptosis and necrosis. A key molecular event is protein S-glutathionylation, and thioltransferase (glutaredoxin) is a specific and efficient catalyst of protein-SSG reduction. In this study 30-min exposure of H9 and Jurkat cells to cadmium inhibited intracellular protein-SSG reduction, and this correlated with inhibition of the thioltransferase system, consistent with thioltransferase being the primary intracellular catalyst of deglutathionylation. The thioredoxin system contributed very little to total deglutathionylase activity. Thioltransferase and GSSG reductase in situ displayed similar dose-response curves (50% inhibition near 10 micrometer cadmium in extracellular buffer). Acute cadmium exposure also initiated apoptosis, with H9 cells being more sensitive than Jurkat. Moreover, transfection with antisense thioltransferase cDNA was incompatible with cell survival. Collectively, these data suggest that thioltransferase has a vital role in sulfhydryl homeostasis and cell survival. In separate experiments, cadmium inhibited the isolated component enzymes of the thioltransferase and thioredoxin systems, consistent with the vicinal dithiol nature of their active sites: thioltransferase (IC(50) approximately 1 micrometer), GSSG reductase (IC(50) approximately 1 micrometer), thioredoxin (IC(50) approximately 8 micrometer), thioredoxin reductase (IC(50) approximately 0.2 micrometer). Disruption of the vicinal dithiol on thioltransferase (via oxidation to C22-SS-C25; or C25S mutation) protected against cadmium, consistent with a dithiol chelation mechanism of inactivation.
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Affiliation(s)
- C A Chrestensen
- Department of Pharmacology, Case Western Reserve University, School of Medicine, Cleveland, Ohio 44106-4965, USA
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