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Jamil M, Cowart LA. Sphingolipids in mitochondria-from function to disease. Front Cell Dev Biol 2023; 11:1302472. [PMID: 38078003 PMCID: PMC10702779 DOI: 10.3389/fcell.2023.1302472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 11/03/2023] [Indexed: 02/12/2024] Open
Abstract
Sphingolipids are not only structural components of cellular membranes but also play vital roles in cell signaling and modulation of cellular processes. Within mitochondria, sphingolipids exert diverse effects on mitochondrial dynamics, energy metabolism, oxidative stress, and cell death pathways. In this review, we summarize literature addressing the crucial role of sphingolipids in mitochondria, highlighting their impact on mitochondrial dynamics, cellular bioenergetics, and important cell processes including apoptosis and mitophagy.
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Affiliation(s)
- Maryam Jamil
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, United States
- Department of Biochemistry and Molecular Biology, Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, United States
| | - Lauren Ashley Cowart
- Department of Biochemistry and Molecular Biology, Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, United States
- Richmond Veteran’s Affairs Medical Center, Richmond, VA, United States
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2
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Zhang B, Xu D, Shao L, Liang H, Li J, Huang C. Toxicity mechanism of patulin on 293 T cells and correlation analysis of Caspase family. Toxicol Res (Camb) 2022; 11:758-764. [PMID: 36337240 PMCID: PMC9618098 DOI: 10.1093/toxres/tfac053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/25/2022] [Accepted: 06/21/2022] [Indexed: 08/27/2023] Open
Abstract
Patulin (PAT), a kind of mycotoxin, is a widely disseminated mycotoxin found in agricultural products. Although the existing research results show that PAT can cause nerve, immune, and skin toxicities, resulting in heart, liver, and kidney damages. However, evidence on the underlying mechanisms of PAT is still lacking. Present study aims to investigate the renal toxicity and related mechanisms of PAT on 293 T cells. Cell Counting Kit-8 method was used to reveal the dose-effect relationship and the time-effect relationship of PAT toxicity. Trypan blue staining and Hoechst 33342 staining were used to analyze PAT, which induced apoptosis on 293 T cells. Superoxide-dismutase (SOD), GSH, and malondialdehyde (MDA) were used to measure the changes of oxidative stress status of 293 T cells induced by PAT. The changes of reactive oxygen species (ROS) and ATP in mitochondria indicate the role of mitochondria when PAT induced cell damage and apoptosis. Through Cyt-C release assay analysis, caspase activity change, and correlation analysis, the potential mechanism of mitochondrial apoptosis pathway was proved. Results demonstrated that PAT significantly induced cell injury, and with the increase of time and concentration, the cell survival rate decreased significantly. Hoechst 33342 staining and Trypan blue staining showed that apoptosis rate was elevated by PAT. As PAT concentration increased, intracellular SOD, glutathion peroxidase activities were decreased and the MDA content was increased. The decrease of intracellular ATP level and accumulation of ROS content indicated an increased permeability of the mitochondrial membrane. Overexpression of Cyt-C activated the cascade reaction of caspase enzyme, leading to apoptosis. The results of enzyme activity assay and correlation analysis indicated that caspase 3 was the most critical caspase in the cascade system and that it was most correlated with caspase 8 and caspase 9.
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Affiliation(s)
- Baigang Zhang
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Dongmei Xu
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Lin Shao
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Hairong Liang
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Jinliang Li
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Chenghui Huang
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
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3
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Jung BC, Lim J, Kim SH, Kim YS. Caspase-8 Potentiates Triglyceride (TG)-Induced Cell Death of THP-1 Macrophages via a Positive Feedback Loop. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2021. [DOI: 10.15324/kjcls.2021.53.2.158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Byung Chul Jung
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, United States
- Department of Biomedical Laboratory Science, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea
| | - Jaewon Lim
- Department of Biomedical Laboratory Science, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea
- Department of Biomedical Laboratory Science, College of Rehabilitation and Health, Daegu Haany University, Gyeongsan, Korea
| | - Sung Hoon Kim
- Department of Biomedical Laboratory Science, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea
- Department of Biomedical Laboratory Science, Korea Nazarene University, Cheonan, Korea
| | - Yoon Suk Kim
- Department of Biomedical Laboratory Science, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea
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4
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Ankawa R, Goldberger N, Yosefzon Y, Koren E, Yusupova M, Rosner D, Feldman A, Baror-Sebban S, Buganim Y, Simon DJ, Tessier-Lavigne M, Fuchs Y. Apoptotic cells represent a dynamic stem cell niche governing proliferation and tissue regeneration. Dev Cell 2021; 56:1900-1916.e5. [PMID: 34197726 DOI: 10.1016/j.devcel.2021.06.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 12/14/2020] [Accepted: 06/09/2021] [Indexed: 12/17/2022]
Abstract
Stem cells (SCs) play a key role in homeostasis and repair. While many studies have focused on SC self-renewal and differentiation, little is known regarding the molecular mechanism regulating SC elimination and compensation upon loss. Here, we report that Caspase-9 deletion in hair follicle SCs (HFSCs) attenuates the apoptotic cascade, resulting in significant temporal delays. Surprisingly, Casp9-deficient HFSCs accumulate high levels of cleaved caspase-3 and are improperly cleared due to an essential caspase-3/caspase-9 feedforward loop. These SCs are retained in an apoptotic-engaged state, serving as mitogenic signaling centers by continuously releasing Wnt3 and instructing proliferation. Investigating the underlying mechanism, we reveal a caspase-3/Dusp8/p38 module responsible for Wnt3 induction, which operates in both normal and Casp9-deleted HFSCs. Notably, Casp9-deleted mice display accelerated wound repair and de novo hair follicle regeneration. Taken together, we demonstrate that apoptotic cells represent a dynamic SC niche, from which emanating signals drive SC proliferation and tissue regeneration.
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Affiliation(s)
- Roi Ankawa
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Nitzan Goldberger
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yahav Yosefzon
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Elle Koren
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Marianna Yusupova
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Daniel Rosner
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Alona Feldman
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Shulamit Baror-Sebban
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, the Hebrew University of Jerusalem, Hadassah Medical School, Jerusalem, Israel
| | - Yosef Buganim
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, the Hebrew University of Jerusalem, Hadassah Medical School, Jerusalem, Israel
| | - David J Simon
- Department of Biochemistry, Weill Cornell Medical College, New York, NY 10065, USA
| | | | - Yaron Fuchs
- Laboratory of Stem Cell Biology and Regenerative Medicine, Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
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5
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Yan S, Liu K, Mu L, Liu J, Tang W, Liu B. Research and application of hydrostatic high pressure in tumor vaccines (Review). Oncol Rep 2021; 45:75. [PMID: 33760193 PMCID: PMC8020208 DOI: 10.3892/or.2021.8026] [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: 02/19/2020] [Accepted: 03/05/2021] [Indexed: 11/29/2022] Open
Abstract
It is well known that hydrostatic pressure (HP) is a physical parameter that is now regarded as an important variable for life. High hydrostatic pressure (HHP) technology has influenced biological systems for more than 100 years. Food and bioscience researchers have shown great interest in HHP technology over the past few decades. The development of knowledge related to this area can better facilitate the application of HHP in the life sciences. Furthermore, new applications for HHP may come from these current studies, particularly in tumor vaccines. Currently, cancer recurrence and metastasis continue to pose a serious threat to human health. The limited efficacy of conventional treatments has led to the need for breakthroughs in immunotherapy and other related areas. Research into tumor vaccines is providing new insights for cancer treatment. The purpose of this review is to present the main findings reported thus far in the relevant scientific literature, focusing on knowledge related to HHP technology and tumor vaccines, and to demonstrate the potential of applying HHP technology to tumor vaccine development.
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Affiliation(s)
- Shuai Yan
- Department of Operating Room, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Kai Liu
- Department of Hand and Foot Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Lin Mu
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jianfeng Liu
- Department of Hand and Foot Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Wan Tang
- Department of Operating Room, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Bin Liu
- Department of Hand and Foot Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
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6
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Vigneswara V, Ahmed Z. The Role of Caspase-2 in Regulating Cell Fate. Cells 2020; 9:cells9051259. [PMID: 32438737 PMCID: PMC7290664 DOI: 10.3390/cells9051259] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022] Open
Abstract
Caspase-2 is the most evolutionarily conserved member of the mammalian caspase family and has been implicated in both apoptotic and non-apoptotic signaling pathways, including tumor suppression, cell cycle regulation, and DNA repair. A myriad of signaling molecules is associated with the tight regulation of caspase-2 to mediate multiple cellular processes far beyond apoptotic cell death. This review provides a comprehensive overview of the literature pertaining to possible sophisticated molecular mechanisms underlying the multifaceted process of caspase-2 activation and to highlight its interplay between factors that promote or suppress apoptosis in a complicated regulatory network that determines the fate of a cell from its birth and throughout its life.
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7
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Song C, Charli A, Luo J, Riaz Z, Jin H, Anantharam V, Kanthasamy A, Kanthasamy AG. Mechanistic Interplay Between Autophagy and Apoptotic Signaling in Endosulfan-Induced Dopaminergic Neurotoxicity: Relevance to the Adverse Outcome Pathway in Pesticide Neurotoxicity. Toxicol Sci 2020; 169:333-352. [PMID: 30796443 DOI: 10.1093/toxsci/kfz049] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Chronic exposure to pesticides is implicated in the etiopathogenesis of Parkinson's disease (PD). Previously, we showed that dieldrin induces dopaminergic neurotoxicity by activating a cascade of apoptotic signaling pathways in experimental models of PD. Here, we systematically investigated endosulfan's effect on the interplay between apoptosis and autophagy in dopaminergic neuronal cell models of PD. Exposing N27 dopaminergic neuronal cells to endosulfan rapidly induced autophagy, indicated by an increased number of autophagosomes and LC3-II accumulation. Prolonged endosulfan exposure (>9 h) triggered apoptotic signaling, including caspase-2 and -3 activation and protein kinase C delta (PKCδ) proteolytic activation, ultimately leading to cell death, thus demonstrating that autophagy precedes apoptosis during endosulfan neurotoxicity. Furthermore, inhibiting autophagy with wortmannin, a phosphoinositide 3-kinase inhibitor, potentiated endosulfan-induced apoptosis, suggesting that autophagy is an early protective response against endosulfan. Additionally, Beclin-1, a major regulator of autophagy, was cleaved during the initiation of apoptotic cell death, and the cleavage was predominantly mediated by caspase-2. Also, caspase-2 and caspase-3 inhibitors effectively blocked endosulfan-induced apoptotic cell death. CRISPR/Cas9-based stable knockdown of PKCδ significantly attenuated endosulfan-induced caspase-3 activation, indicating that the kinase serves as a regulatory switch for apoptosis. Additional studies in primary mesencephalic neuronal cultures confirmed endosulfan's effect on autophagy and neuronal degeneration. Collectively, our results demonstrate that a functional interplay between autophagy and apoptosis dictate pesticide-induced neurodegenerative processes in dopaminergic neuronal cells. Our study provides insight into cell death mechanisms in environmentally linked neurodegenerative diseases.
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Affiliation(s)
| | - Adhithiya Charli
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Jie Luo
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Zainab Riaz
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Huajun Jin
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Vellareddy Anantharam
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Arthi Kanthasamy
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Anumantha G Kanthasamy
- Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
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8
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Bíliková P, Švandová E, Veselá B, Doubek J, Poliard A, Matalová E. Coupling Activation of Pro-Apoptotic Caspases With Autophagy in the
Meckel´s Cartilage. Physiol Res 2018; 68:135-140. [DOI: 10.33549/physiolres.933947] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mammalian Meckel´s cartilage is a temporary structure associated with mandible development. Notably, its elimination is not executed by apoptosis, and autophagy was suggested as the major mechanism. Simultaneous reports point to pro-apoptotic caspases as novel participants in autophagic pathways in general. The aim of this research was to find out whether activation of pro-apoptotic caspases (-2, -3, -6, -7, -8 and -9) was associated with autophagy of the Meckel´s cartilage chondrocytes. Active caspases were examined in serial histological sections of mouse mandible using immunodetection and were correlated with incidence of autophagy based on Beclin-1 expression. Caspase-2 and caspase-8 were found in Beclin-1 positive regions, whereas caspase-3, -6, -7 and -9 were not present. Caspase-8 was further correlated with Fas/FasL and HIF-1alpha, potential triggers for its activation. Some Fas and FasL positivity was observed in the chondrocytes but caspase-8 activation was found also in FasL deficient cartilage. HIF-1alpha was abundantly present in the hypertrophic chondrocytes. Taken together, caspase-8 activation in the Meckel´s cartilage was demonstrated for the first time. Caspase-8 and caspase-2 were the only pro-apoptotic caspases detected in the Beclin-1 positive segment of the cartilage. Activation of caspase-8 appears FasL/Fas independent but may be switched on by HIF-1alpha.
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Affiliation(s)
- P. Bíliková
- Department of Physiology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - E. Švandová
- Department of Physiology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - B. Veselá
- Department of Physiology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - J. Doubek
- Department of Physiology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - A. Poliard
- Laboratory of Orofacial Pathologies, Imaging and Biotherapies, Université Paris Descartes, France
| | - E Matalová
- Department of Physiology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
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9
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Wilson CH, Kumar S. Caspases in metabolic disease and their therapeutic potential. Cell Death Differ 2018; 25:1010-1024. [PMID: 29743560 PMCID: PMC5988802 DOI: 10.1038/s41418-018-0111-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/26/2018] [Accepted: 03/22/2018] [Indexed: 12/13/2022] Open
Abstract
Caspases, a family of cysteine-dependent aspartate-specific proteases, are central to the maintenance of cellular and organismal homoeostasis by functioning as key mediators of the inflammatory response and/or apoptosis. Both metabolic inflammation and apoptosis play a central role in the pathogenesis of metabolic disease such as obesity and the progression of nonalcoholic steatohepatisis (NASH) to more severe liver disease. Obesity and nonalcoholic fatty liver disease (NAFLD) are the leading global health challenges associated with the development of numerous comorbidities including insulin resistance, type-2 diabetes and early mortality. Despite the high prevalence, current treatment strategies including lifestyle, dietary, pharmaceutical and surgical interventions, are often limited in their efficacy to manage or treat obesity, and there are currently no clinical therapies for NAFLD/NASH. As mediators of inflammation and cell death, caspases are attractive therapeutic targets for the treatment of these metabolic diseases. As such, pan-caspase inhibitors that act by blocking apoptosis have reached phase I/II clinical trials in severe liver disease. However, there is still a lack of knowledge of the specific and differential functions of individual caspases. In addition, cross-talk between alternate cell death pathways is a growing concern for long-term caspase inhibition. Evidence is emerging of the important cell-death-independent, non-apoptotic functions of caspases in metabolic homoeostasis that may be of therapeutic value. Here, we review the current evidence for roles of caspases in metabolic disease and discuss their potential targeting as a therapeutic strategy.
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Affiliation(s)
- Claire H Wilson
- Centre for Cancer Biology, University of South Australia & SA Pathology, Adelaide, SA, 5001, Australia.
| | - Sharad Kumar
- Centre for Cancer Biology, University of South Australia & SA Pathology, Adelaide, SA, 5001, Australia.
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10
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Scarpa ES, Mari M, Antonini E, Palma F, Ninfali P. Natural and synthetic avenanthramides activate caspases 2, 8, 3 and downregulate hTERT, MDR1 and COX-2 genes in CaCo-2 and Hep3B cancer cells. Food Funct 2018; 9:2913-2921. [DOI: 10.1039/c7fo01804e] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Avenanthramides inhibit proliferation of CaCo-2 and Hep3B cancer cells through induction of apoptosis and downregulation of pro-survival mechanisms.
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Affiliation(s)
- E. S. Scarpa
- Department of Biomolecular Sciences
- University of Urbino Carlo Bo
- 61029 Urbino
- Italy
| | - M. Mari
- Department of Biomolecular Sciences
- University of Urbino Carlo Bo
- 61029 Urbino
- Italy
| | - E. Antonini
- Department of Biomolecular Sciences
- University of Urbino Carlo Bo
- 61029 Urbino
- Italy
| | - F. Palma
- Department of Biomolecular Sciences
- University of Urbino Carlo Bo
- 61029 Urbino
- Italy
| | - P. Ninfali
- Department of Biomolecular Sciences
- University of Urbino Carlo Bo
- 61029 Urbino
- Italy
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11
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Platelet hyperactivation, apoptosis and hypercoagulability in patients with acute pulmonary embolism. Thromb Res 2017; 155:106-115. [PMID: 28528289 DOI: 10.1016/j.thromres.2017.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 04/29/2017] [Accepted: 05/10/2017] [Indexed: 12/13/2022]
Abstract
Changes in systemic redox balance can alter platelet activation and aggregation. Acute pulmonary embolism (PE) is a systematic inflammatory disease associated with mechanical shear stress, increased thrombin, catecholamines, serotonin and hemolysis, which cumulatively can hyperactivate platelets and accelerate their turnover. We tested the hypothesis that platelets from patients with moderately severe PE will show hyperstimulation and a pre-apoptotic phenotype associated with microparticles (MPs) in plasma. Blood for platelet respiration and thromboelastography (TEG) was obtained at diagnosis and 24h later from patients (n=76) with image-proven PE, SBP>90mmHg and right ventricular dysfunction demonstrated by echocardiogram or elevated biomarkers. Controls (n=12) were healthy volunteers. At diagnosis, platelets from PE patients had significantly elevated baseline oxygen consumption compared with controls, explained primarily by accelerated electron transport and oxygen wasting with no measurable extramitochondrial oxygen consumption. On thromboelastography, unstimulated thrombin-independent maximum amplitude was increased with PE, 19±14.1 vs.10.5±7.8mm in controls (p=0.002). Compared with controls, platelets from PE patients showed elevated mitochondrial reactive oxygen species with decreased mitochondrial Bcl-2 protein content and increased cytosolic cytochrome C, coincident with strong annexin V binding, P selectin release from lysed platelets and in plasma MPs compared to controls (p<0.05). These results show evidence of platelet hyperactivation and apoptosis in patients with acute PE, and provide preliminary theoretical basis for further exploration of platelet inhibition in patients with more severe PE.
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12
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Abstract
The sphingolipid family of lipids modulate several cellular processes, including proliferation, cell cycle regulation, inflammatory signaling pathways, and cell death. Several members of the sphingolipid pathway have opposing functions and thus imbalances in sphingolipid metabolism result in deregulated cellular processes, which cause or contribute to diseases and disorders in humans. A key cellular process regulated by sphingolipids is apoptosis, or programmed cell death. Sphingolipids play an important role in both extrinsic and intrinsic apoptotic pathways depending on the stimuli, cell type and cellular response to the stress. During mitochondrial-mediated apoptosis, multiple pathways converge on mitochondria and induce mitochondrial outer membrane permeabilization (MOMP). MOMP results in the release of intermembrane space proteins such as cytochrome c and Apaf1 into the cytosol where they activate the caspases and DNases that execute cell death. The precise molecular components of the pore(s) responsible for MOMP are unknown, but sphingolipids are thought to play a role. Here, we review evidence for a role of sphingolipids in the induction of mitochondrial-mediated apoptosis with a focus on potential underlying molecular mechanisms by which altered sphingolipid metabolism indirectly or directly induce MOMP. Data available on these mechanisms is reviewed, and the focus and limitations of previous and current studies are discussed to present important unanswered questions and potential future directions.
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Affiliation(s)
- Gauri A Patwardhan
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA
| | - Levi J Beverly
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA.,Department of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA
| | - Leah J Siskind
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA. .,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA.
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13
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Jiang J, Li L, Xie M, Fuji R, Liu S, Yin X, Li G, Wang Z. SPATA4 Counteracts Etoposide-Induced Apoptosis via Modulating Bcl-2 Family Proteins in HeLa Cells. Biol Pharm Bull 2016; 38:1458-63. [PMID: 26424010 DOI: 10.1248/bpb.b15-00117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spermatogenesis associated 4 (SPATA4) is a testis-specific gene first cloned by our laboratory, and plays an important role in maintaining the physiological function of germ cells. Accumulated evidence suggests that SPATA4 might be associated with apoptosis. Here we established HeLa cells that stably expressed SPATA4 to investigate the function of SPATA4 in apoptosis. SPATA4 protected HeLa cells from etoposide-induced apoptosis through the mitochondrial apoptotic pathway, in the way that SPATA4 suppressed decrease of the mitochondrial membrane potential, the release of cytochrome c, and subsequent activation of caspase-9 and -3. We further demonstrated that SPATA4 upregulated anti-apoptotic members of Bcl-2 family proteins, Bcl-2, and downregulated the pro-apoptotic member of Bcl-2 family proteins, Bax. Knockdown of SPATA4 in HeLa/SPATA4 cells could partially rescue expression levels of bcl-2 and bax. In conclusion, SPATA4 protects HeLa cells against etoposide-induced apoptosis through the mitochondrial apoptotic pathway. Our findings provide further evidence that SPATA4 plays a role in regulating apoptosis.
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Affiliation(s)
- Junjun Jiang
- MOE Key Laboratory of Protein Sciences, Department of Pharmacology, School of Medicine, Tsinghua University
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14
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Zhu X, Zhou Y, Tao R, Zhao J, Chen J, Liu C, Xu Z, Bao G, Zhang J, Chen M, Shen J, Cheng C, Zhang D. Upregulation of PTP1B After Rat Spinal Cord Injury. Inflammation 2016; 38:1891-902. [PMID: 25894283 DOI: 10.1007/s10753-015-0169-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Protein tyrosine phosphatase 1B (PTP1B), a member of the protein tyrosine phosphatase family, attaches to the endoplasmic reticulum (ER) via its C-terminal tail. Previous studies have reported that PTP1B participates in various signal transduction pathways in many human diseases, including diabetes, cancers, osteoporosis, and obesity. It also plays an important role in the ER stress. ER stress induced by spinal cord injury (SCI) was reported to result in cell apoptosis. Till now, the role of PTP1B in the injury of the central nervous system remains unknown. In the present study, we built an adult rat SCI model to investigate the potential role of PTP1B in SCI. Western blot analysis detected a notable alteration of PTP1B expression after SCI. Immunohistochemistry indicated that PTP1B expressed at a low level in the normal spinal cord and greatly increased after SCI. Double immunofluorescence staining revealed that PTP1B immunoreactivity was predominantly increased in neurons following SCI. In addition, SCI resulted in a significant alteration in the level of active caspase-3, caspase-12, and 153/C/EBP homologous transcription factor protein, which were correlated with the upregulation of PTP1B. Co-localization of PTP1B/active caspase-3 was also detected in neurons. Taken together, our findings elucidated the PTP1B expression in the SCI for the first time. These results suggested that PTP1B might be deeply involved in the injury response and probably played an important role in the neuro-pathological process of SCI.
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Affiliation(s)
- Xinhui Zhu
- Department of Osteology, The Second Affiliated Hospital, Nantong University, Nantong, 226001, People's Republic of China
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Li YL, Lin ML, He SQ, Jin JF. Sphingolipid metabolism affects the anticancer effect of cisplatin. World J Transl Med 2016; 5:37-45. [DOI: 10.5528/wjtm.v5.i1.37] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/09/2015] [Accepted: 01/11/2016] [Indexed: 02/06/2023] Open
Abstract
Cisplatin, a DNA crosslinking agent, is widely used for the treatment of a variety of solid tumors. Numerous studies have demonstrated that sphingolipid metabolism, which acts as a target for cisplatin treatment, is a highly complex network that consists of sphingolipid signaling molecules and related catalytic enzymes. Ceramide (Cer), which is the central molecule of this network, has been established to induce apoptosis. However, another molecule, sphingosine-1-phosphate (S1P), exerts the opposite function, i.e., serves as a regulator of pro-survival. Other sphingolipid molecules, including dihydroceramide, ceramide-1-phosphate, glucosylceramide (GluCer), and sphingosine (Sph), or sphingolipid catalytic enzymes such as Sph kinase (SphK), Cer synthase (CerS), and S1P lyase, have also attracted considerable attention, particularly Cer, GluCer, SphK, CerS, and S1P lyase, which have been implicated in cisplatin resistance. This review summarizes specific molecules involved in sphingolipid metabolism and related catalytic enzymes affecting the anticancer effect of cisplatin, particularly in relation to induction of apoptosis and drug resistance.
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Philchenkov AA, Zavelevych MP. RHAMNAZIN INHIBITS PROLIFERATION AND INDUCES APOPTOSIS OF HUMAN JURKAT LEUKEMIA CELLS IN VITRO. UKRAINIAN BIOCHEMICAL JOURNAL 2016; 87:122-8. [PMID: 27025066 DOI: 10.15407/ubj87.06.122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Antiproliferative and apoptogenic effects of rhamnazin, a dimethoxylated derivative of quercetin, were studied in human acute lymphoblastic leukemia Jurkat cells. The cytotoxicity and apoptogenic activity of rhamnazin in vitro are inferior to that of quercetin. The apoptogenic activity of rhamnazin is realized via mitochondrial pathway and associated with activation of caspase-9 and -3. The additive apoptogenic effect of rhamnazin and suboptimal doses of etoposide, a DNA topoisomerase II inhibitor, is demonstrated. Therefore, methylation of quercetin modifies its biological effects considerably.
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Lin CF, Tsai CC, Huang WC, Wang YC, Tseng PC, Tsai TT, Chen CL. Glycogen Synthase Kinase-3β and Caspase-2 Mediate Ceramide- and Etoposide-Induced Apoptosis by Regulating the Lysosomal-Mitochondrial Axis. PLoS One 2016; 11:e0145460. [PMID: 26727221 PMCID: PMC4699703 DOI: 10.1371/journal.pone.0145460] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/03/2015] [Indexed: 11/18/2022] Open
Abstract
Glycogen synthase kinase-3β (GSK-3β) regulates the sequential activation of caspase-2 and caspase-8 before mitochondrial apoptosis. Here, we report the regulation of Mcl-1 destabilization and cathepsin D-regulated caspase-8 activation by GSK-3β and caspase-2. Treatment with either the ceramide analogue C2-ceramide or the topoisomerase II inhibitor etoposide sequentially induced lysosomal membrane permeabilization (LMP), the reduction of mitochondrial transmembrane potential, and apoptosis. Following LMP, cathepsin D translocated from lysosomes to the cytoplasm, whereas inhibiting cathepsin D blocked mitochondrial apoptosis. Furthermore, cathepsin D caused the activation of caspase-8 but not caspase-2. Inhibiting GSK-3β and caspase-2 blocked Mcl-1 destabilization, LMP, cathepsin D re-localization, caspase-8 activation, and mitochondrial apoptosis. Expression of Mcl-1 was localized to the lysosomes, and forced expression of Mcl-1 prevented apoptotic signaling via the lysosomal-mitochondrial pathway. These results demonstrate the importance of GSK-3β and caspase-2 in ceramide- and etoposide-induced apoptosis through mechanisms involving Mcl-1 destabilization and the lysosomal-mitochondrial axis.
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Affiliation(s)
- Chiou-Feng Lin
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
| | - Cheng-Chieh Tsai
- Department of Nursing, Chung Hwa University of Medical Technology, Tainan, 717, Taiwan
| | - Wei-Ching Huang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Yu-Chih Wang
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
| | - Po-Chun Tseng
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, 701, Taiwan
| | - Tsung-Ting Tsai
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan
| | - Chia-Ling Chen
- Translational Research Center, Taipei Medical University, Taipei, 110, Taiwan
- * E-mail:
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18
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Suzuki O, Abe M, Hashimoto Y. Caspase-dependent drug-induced apoptosis is regulated by cell surface sialylation in human B-cell lymphoma. Oncol Lett 2015; 10:687-690. [PMID: 26622554 DOI: 10.3892/ol.2015.3320] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 05/01/2015] [Indexed: 01/06/2023] Open
Abstract
The important role of sialic acid in various biological phenomena is well-established. In order to further clarify the role of sialic acid in cell death induced by various stimuli, the present study compared the cell survival of the HBL-2 human diffuse large B-cell lymphoma cell line upon anticancer drug-induced cell death, with or without neuraminidase pretreatment: Cell survival was assessed using flow cytometry. Upon treatment with doxorubicin or etoposide, the HBL-2 cell viability decreased. In etoposide-induced cell death, the HBL-2 cells demonstrated nuclear fragmentation, which was consistent with morphologically apoptotic cells. In addition, a higher decrease in the cell viability of etoposide-treated HBL-2 cells was observed in cells pretreated with neuraminidase compared with cells that were not pretreated. Furthermore, the caspase-3, caspase-8 and caspase-9 activities in etoposide-induced apoptosis demonstrated a greater increase upon neuraminidase pretreatment compared with no neuraminidase pretreatment. In conclusion, cell surface sialylation appears to protect lymphoma cells from anticancer drug-induced apoptosis.
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Affiliation(s)
- Osamu Suzuki
- Department of Diagnostic Pathology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Masafumi Abe
- Department of Diagnostic Pathology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Yuko Hashimoto
- Department of Diagnostic Pathology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
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19
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Glutathione depletion regulates both extrinsic and intrinsic apoptotic signaling cascades independent from multidrug resistance protein 1. Apoptosis 2014; 19:117-34. [PMID: 24146141 DOI: 10.1007/s10495-013-0900-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Glutathione (GSH) depletion is an important hallmark of apoptosis. We previously demonstrated that GSH depletion, by its efflux, regulates apoptosis by modulation of executioner caspase activity. However, both the molecular identity of the GSH transporter(s) involved and the signaling cascades regulating GSH loss remain obscure. We sought to determine the role of multidrug resistance protein 1 (MRP1) in GSH depletion and its regulatory role on extrinsic and intrinsic pathways of apoptosis. In human lymphoma cells, GSH depletion was stimulated rather than inhibited by pharmacological blockage of MRP1 with MK571. GSH loss was dependent on initiator caspases 8 and 9 activity. Genetic knock-down (>60 %) of MRP1 by stable transfection with short hairpin small interfering RNA significantly reduced MRP1 protein levels, which correlated directly with the loss of MRP1-mediated anion transport. However, GSH depletion and apoptosis induced by both extrinsic and intrinsic pathways were not affected by MRP1 knock-down. Interestingly, stimulation of GSH loss by MK571 also enhanced the initiator phase of apoptosis by stimulating initiator caspase 8 and 9 activity and pro-apoptotic BCL-2 interacting domain cleavage. Our results clearly show that caspase-dependent GSH loss and apoptosis are not mediated by MRP1 proteins and that GSH depletion stimulates the initiation phase of apoptosis in lymphoid cells.
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20
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Yang CS, Matsuura K, Huang NJ, Robeson AC, Huang B, Zhang L, Kornbluth S. Fatty acid synthase inhibition engages a novel caspase-2 regulatory mechanism to induce ovarian cancer cell death. Oncogene 2014; 34:3264-72. [PMID: 25151963 PMCID: PMC4340825 DOI: 10.1038/onc.2014.271] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 07/11/2014] [Accepted: 07/19/2014] [Indexed: 12/22/2022]
Abstract
Blockade of fatty acid synthase (FASN), a key enzyme involved in de novo lipogenesis, results in robust death of ovarian cancer cells. However, known FASN inhibitors have proven to be poor therapeutic agents due to their ability to induce cachexia. Therefore, we sought to identify additional targets in the pathway linking FASN inhibition and cell death whose modulation might kill ovarian cancer cells without the attendant side effects. Here, we show that the initiator caspase-2 is required for robust death of ovarian cancer cells induced by FASN inhibitors. REDD1 (also known as Rtp801 or DDIT4), a known mTOR inhibitor previously implicated in the response to FASN inhibition, is a novel caspase-2 regulator in this pathway. REDD1 induction is compromised in ovarian cancer cells that do not respond to FASN inhibition. Inhibition of FASN induced an ATF4-dependent transcriptional induction of REDD1; downregulation of REDD1 prevented orlistat-induced activation of caspase-2, as monitored by its cleavage, proteolytic activity, and dimerization. Abrogation of REDD1-mediated suppression of mTOR by TSC2 RNAi protected FASN inhibitor-sensitive ovarian cancer cells (OVCA 420 cells) from orlistat-induced death. Conversely, suppression of mTOR with the chemical inhibitors PP242 or rapamycin sensitized DOV13, an ovarian cancer cell line incapable of inducing REDD1, to orlistat-induced cell death through caspase-2. These findings indicate that REDD1 positively controls caspase-2-dependent cell death of ovarian cancer cells by inhibiting mTOR, placing mTOR as a novel upstream regulator of caspase-2 and supporting the possibility of manipulating mTOR to enhance caspase-2 activation in ovarian cancer.
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Affiliation(s)
- C-S Yang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - K Matsuura
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - N-J Huang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - A C Robeson
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - B Huang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - L Zhang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - S Kornbluth
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
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21
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Lin LT, Wu SJ, Lin CC. The Anticancer Properties and Apoptosis-inducing Mechanisms of Cinnamaldehyde and the Herbal Prescription Huang-Lian-Jie-Du-Tang ( Huáng Lián Jiě Dú Tang) in Human Hepatoma Cells. J Tradit Complement Med 2014; 3:227-33. [PMID: 24716182 PMCID: PMC3924998 DOI: 10.4103/2225-4110.119732] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Hepatocellular carcinoma (HCC) has long been one of the most important causes of cancer mortality in the world. Many natural products and traditional herbal medicines have been used to treat HCC in Asian countries such as Japan, Korea, Taiwan, and China. The present review aims to describe the anticancer properties and apoptotic mechanisms of cinnamaldehyde, the bioactive ingredient isolated from cinnamon trees, and the herbal prescription Huang-Lian-Jie-Du-Tang (黃連解毒湯 Huáng Lián Jiě Dú Tang; HLJDT) against human hepatoma cells in vitro and in vivo. Implication of their treatment for the development of targeted therapy against HCC is discussed.
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Affiliation(s)
- Liang-Tzung Lin
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Shu-Jing Wu
- Department of Nutritional Health, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Chun-Ching Lin
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
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22
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Mhaidat NM, Bouklihacene M, Thorne RF. 5-Fluorouracil-induced apoptosis in colorectal cancer cells is caspase-9-dependent and mediated by activation of protein kinase C-δ. Oncol Lett 2014; 8:699-704. [PMID: 25013487 PMCID: PMC4081407 DOI: 10.3892/ol.2014.2211] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 05/13/2014] [Indexed: 02/07/2023] Open
Abstract
Elucidation of the molecular mechanisms by which 5-fluorouracil (5-FU) induces apoptosis is required in order to understand the resistance of colorectal cancer (CRC) cells to 5-FU. In the current study, 5-FU-induced apoptosis was assessed using the propidium iodide method. Involvement of protein kinase C (PKC) was assessed by evaluating the extent of their activation in CRC, following treatment with 5-FU, using biochemical inhibitors and western blot analysis. The results revealed that 5-FU induces varying degrees of apoptosis in CRC cells; HCT116 cells were identified to be the most sensitive cells and SW480 were the least sensitive. In addition, 5-FU-induced apoptosis was caspase-dependent as it appeared to be initiated by caspase-9. Furthermore, PKCɛ was marginally expressed in CRC cells and no changes were observed in the levels of cleavage or phosphorylation following treatment with 5-FU. The treatment of HCT116 cells with 5-FU increased the expression, phosphorylation and cleavage of PKCδ. The inhibition of PKCδ was found to significantly inhibit 5-FU-induced apoptosis. These results indicated that 5-FU induces apoptosis in CRC by the activation of PKCδ and caspase-9. In addition, the levels of PKCδ activation may determine the sensitivity of CRC to 5-FU.
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Affiliation(s)
- Nizar M Mhaidat
- Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Mohammed Bouklihacene
- Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Rick F Thorne
- Department of Cancer Research Unit, Newcastle University, Newcastle, NSW 2300, Australia
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23
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Analysis of the minimal specificity of caspase-2 and identification of Ac-VDTTD-AFC as a caspase-2-selective peptide substrate. Biosci Rep 2014; 34:BSR20140025. [PMID: 27919034 PMCID: PMC3966047 DOI: 10.1042/bsr20140025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 02/12/2014] [Accepted: 02/13/2014] [Indexed: 11/17/2022] Open
Abstract
Caspase-2 is an evolutionarily conserved but enigmatic protease whose biological role remains poorly understood. To date, research into the functions of caspase-2 has been hampered by an absence of reagents that can distinguish its activity from that of the downstream apoptotic caspase, caspase-3. Identification of protein substrates of caspase-2 that are efficiently cleaved within cells may also provide clues to the role of this protease. We used a yeast-based transcriptional reporter system to define the minimal substrate specificity of caspase-2. The resulting profile enabled the identification of candidate novel caspase-2 substrates. Caspase-2 cleaved one of these proteins, the cancer-associated transcription factor Runx1, although with relatively low efficiency. A fluorogenic peptide was derived from the sequence most efficiently cleaved in the context of the transcriptional reporter. This peptide, Ac-VDTTD-AFC, was efficiently cleaved by purified caspase-2 and auto-activating caspase-2 in mammalian cells, and exhibited better selectivity for caspase-2 relative to caspase-3 than reagents that are currently available. We suggest that this reagent, used in parallel with the traditional caspase-3 substrate Ac-DEVD-AFC, will enable researchers to monitor caspase-2 activity in cell lysates and may assist in the determination of stimuli that activate caspase-2 in vivo.
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24
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Jung EB, Kim YJ, Lee CS. Casein kinase 2 inhibition attenuates cholesterol oxidation product-induced apoptosis by suppressing the activation of the mitochondrial pathway and the caspase-8- and bid-dependent pathways. Neurochem Int 2014; 65:30-9. [PMID: 24398405 DOI: 10.1016/j.neuint.2013.12.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/21/2013] [Accepted: 12/29/2013] [Indexed: 11/25/2022]
Abstract
Protein casein kinase 2 is involved in signal transduction, cell growth and apoptosis. However, it is unclear whether the cholesterol oxidation product-induced cell death is regulated by casein kinase 2. Therefore, in the respect of the cell death process, we assessed the regulatory effect of the casein kinase 2 on the cholesterol oxidation product-induced apoptosis in neuronal cells using differentiated PC12 cells. Casein kinase 2 inhibitors (4,5,6,7-tetrabromobezotriazole (TBB) and apigenin) which do not have toxic effects, reduced the 7-ketocholesterol or 25-hydroxycholesterol-induced cell death and nuclear damage in PC12 cells. Treatment with TBB inhibited the 7-ketocholesterol-induced decrease in Bid, Bcl-2 and survivin protein levels, increase in Bax levels, loss of the mitochondrial transmembrane potential, cytochrome c release, activation of caspases (-8, -9 and -3), cleavage of PARP-1, and increase in the tumor suppressor p53 levels. The results showed that the casein kinase 2 inhibitor at the concentrations tested which does not induce toxic effects, may attenuate the cholesterol oxidation product-induced apoptosis in differentiated PC12 cells by suppressing the activation of the mitochondrial pathway and the caspase-8- and Bid-dependent pathways. The preventive effect appears to be ascribed to its inhibitory effect on the formation of reactive oxygen species and depletion of GSH.
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Affiliation(s)
- Eun Byul Jung
- Department of Pharmacology, College of Medicine, and the BK21(plus) Skin Barrier Network Human Resources Development Team, Chung-Ang University, Seoul 156-756, South Korea
| | - Yun Jeong Kim
- Department of Pharmacology, College of Medicine, and the BK21(plus) Skin Barrier Network Human Resources Development Team, Chung-Ang University, Seoul 156-756, South Korea
| | - Chung Soo Lee
- Department of Pharmacology, College of Medicine, and the BK21(plus) Skin Barrier Network Human Resources Development Team, Chung-Ang University, Seoul 156-756, South Korea.
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25
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Choi EJ, Kim SM, Shin JH, Kim S, Song KJ, Kee SH. Involvement of caspase-2 activation in aurora kinase inhibitor-induced cell death in axin-expressing L929 cells. Apoptosis 2013; 19:657-67. [DOI: 10.1007/s10495-013-0951-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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Bronner DN, O'Riordan MXD, He Y. Caspase-2 mediates a Brucella abortus RB51-induced hybrid cell death having features of apoptosis and pyroptosis. Front Cell Infect Microbiol 2013; 3:83. [PMID: 24350060 PMCID: PMC3842122 DOI: 10.3389/fcimb.2013.00083] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/30/2013] [Indexed: 01/08/2023] Open
Abstract
Programmed cell death (PCD) can play a crucial role in tuning the immune response to microbial infection. Although PCD can occur in different forms, all are mediated by a family of proteases called caspases. Caspase-2 is the most conserved caspase, however, its function in cell death is ill-defined. Previously we demonstrated that live attenuated cattle vaccine strain Brucella abortus RB51 induces caspase-2-mediated and caspase-1-independent PCD of infected macrophages. We also discovered that rough attenuated B. suis strain VTRS1 induces a caspase-2-mediated and caspase-1-independent proinflammatory cell death in infected macrophages, which was tentatively coined "caspase-2-mediated pyroptosis". However, the mechanism of caspase-2-mediated cell death pathway remained unclear. In this study, we found that caspase-2 mediated proinflammatory cell death of RB51-infected macrophages and regulated many genes in different PCD pathways. We show that the activation of proapoptotic caspases-3 and -8 was dependent upon caspase-2. Caspase-2 regulated mitochondrial cytochrome c release and TNFα production, both of which are known to activate caspase-3 and caspase-8, respectively. In addition to TNFα, RB51-induced caspase-1 and IL-1β production was also driven by caspase-2-mediated mitochondrial dysfunction. Interestingly, pore formation, a phenomenon commonly associated with caspase-1-mediated pyroptosis, occurred; however, unlike its role in S. typhimurium-induced pyroptosis, pore formation did not contribute to RB51-induced proinflammatory cell death. Our data suggest that caspase-2 acts as an initiator caspase that mediates a novel RB51-induced hybrid cell death that simulates but differs from typical non-proinflammatory apoptosis and caspase-1-mediated proinflammatory pyroptosis. The initiator role of the caspase-2-mediated cell death was also conserved in cellular stress-induced cell death of macrophages treated with etoposide, naphthalene, or anti-Fas. Caspase-2 also regulated caspase-3 and -8 activation, as well as cell death in macrophages treated with each of the three reagents. Taken together, our data has demonstrated that caspase-2 can play an important role in mediating a proinflammatory response and a hybrid cell death that demonstrates features of both apoptosis and pyroptosis.
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Affiliation(s)
- Denise N Bronner
- Department of Microbiology and Immunology, University of Michigan Medical School Ann Arbor, MI, USA
| | - Mary X D O'Riordan
- Department of Microbiology and Immunology, University of Michigan Medical School Ann Arbor, MI, USA
| | - Yongqun He
- Department of Microbiology and Immunology, University of Michigan Medical School Ann Arbor, MI, USA ; Unit for Laboratory Animal Medicine, University of Michigan Medical School Ann Arbor, MI, USA ; Comprehensive Cancer Center, University of Michigan Medical School Ann Arbor, MI, USA
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27
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Mitigation of radiation injury by selective stimulation of the LPA(2) receptor. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:117-25. [PMID: 23127512 DOI: 10.1016/j.bbalip.2012.08.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 08/28/2012] [Accepted: 08/31/2012] [Indexed: 11/21/2022]
Abstract
Due to its antiapoptotic action, derivatives of the lipid mediator lysophosphatidic acid (LPA) provide potential therapeutic utility in diseases associated with programmed cell death. Apoptosis is one of the major pathophysiological processes elicited by radiation injury to the organism. Consequently, therapeutic explorations applying compounds that mimic the antiapoptotic action of LPA have begun. Here we present a brief account of our decade-long drug discovery effort aimed at developing LPA mimics with a special focus on specific agonists of the LPA(2) receptor subtype, which was found to be highly effective in protecting cells from apoptosis. We describe new evidence that 2-((3-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)propyl)thio)benzoic acid (GRI977143), a prototypic nonlipid agonist specific to the LPA(2) receptor subtype, rescues apoptotically condemned cells in vitro and in vivo from injury caused by high-dose γ-irradiation. GRI977143 shows the features of a radiomitigator because it is effective in rescuing the lives of mice from deadly levels of radiation when administered 24h after radiation exposure. Our findings suggest that by specifically activating LPA(2) receptors GRI977143 activates the ERK1/2 prosurvival pathway, effectively reduces Bax translocation to the mitochondrion, attenuates the activation of initiator and effector caspases, reduces DNA fragmentation, and inhibits PARP-1 cleavage associated with γ-irradiation-induced apoptosis. GRI977143 also inhibits bystander apoptosis elicited by soluble proapoptotic mediators produced by irradiated cells. Thus, GRI977143 can serve as a prototype scaffold for lead optimization paving the way to more potent analogs amenable for therapeutic exploration. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.
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28
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Neuroprotective effect of suppression of astrocytic activation by arundic acid on brain injuries in rats with acute subdural hematomas. Brain Res 2013; 1519:127-35. [DOI: 10.1016/j.brainres.2013.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 04/17/2013] [Accepted: 05/01/2013] [Indexed: 11/21/2022]
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29
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Liu H, Wu X, Dong Z, Luo Z, Zhao Z, Xu Y, Zhang JT. Fatty acid synthase causes drug resistance by inhibiting TNF-α and ceramide production. J Lipid Res 2013; 54:776-785. [PMID: 23319743 DOI: 10.1194/jlr.m033811] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Fatty acid synthase (FASN) is a key enzyme in the synthesis of palmitate, the precursor of major nutritional, energetic, and signaling lipids. FASN expression is upregulated in many human cancers and appears to be important for cancer cell survival. Overexpression of FASN has also been found to associate with poor prognosis and higher risk of recurrence of human cancers. Indeed, elevated FASN expression has been shown to contribute to drug resistance. However, the mechanism of FASN-mediated drug resistance is currently unknown. In this study, we show that FASN overexpression causes resistance to multiple anticancer drugs via inhibiting drug-induced ceramide production, caspase 8 activation, and apoptosis. We also show that FASN overexpression suppresses tumor necrosis factor-α production and nuclear factor-κB activation as well as drug-induced activation of neutral sphingomyelinase. Thus, TNF-α may play an important role in mediating FASN function in drug resistance.
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Affiliation(s)
- Hailan Liu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN
| | - Xi Wu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN
| | - Zizheng Dong
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN
| | - Zhiyong Luo
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN
| | - Zhenwen Zhao
- Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis, IN
| | - Yan Xu
- Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis, IN; IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN
| | - Jian-Ting Zhang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN; IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN
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30
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5-Phenylselenyl- and 5-methylselenyl-methyl-2'-deoxyuridine induce oxidative stress, DNA damage, and caspase-2-dependent apoptosis in cancer cells. Apoptosis 2012; 17:200-16. [PMID: 22002103 DOI: 10.1007/s10495-011-0665-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In the present study, we investigated the signaling pathways implicated in the induction of apoptosis by two modified nucleosides, 5-phenylselenyl-methyl-2'-deoxyuridine (PhSe-T) and 5-methylselenyl-methyl-2'-deoxyuridine (MeSe-T), using human cancer cell lines. The induction of apoptosis was associated with proteolytic activation of caspase-3 and -9, PARP cleavage, and decreased levels of IAP family members, including c-IAP-1 and c-IAP-2, but had no effect on XIAP and survivin. PhSe-T and MeSe-T also enhanced the activities of caspase-2 and -8, Bid cleavage, and the conformational activation of Bax. Additionally, nucleoside derivative-induced apoptosis was inhibited by the selective inhibitors of caspase-2, -3, -8, and -9 and also by si-RNAs against caspase-2, -3, -8, and -9; however, inhibition of caspase-2 and -3 was more effective at preventing apoptosis than inhibition of caspase-8 and -9. Moreover, the inhibition of caspase-2 activation by the pharmacological inhibitor z-VDVAD-fmk or by the knockdown of protein expression using siRNA suppressed nucleoside derivative-induced caspase-3 activation, but not vice versa. PhSe-T and MeSe-T also induced a Δψ(m) loss via a CsA-insensitive mechanism, ROS production, and DNA damage, including strand breaks. Moreover, ROS scavengers such as NAC, tiron, and quercetin inhibited nucleoside derivative-induced ROS generation and apoptosis by blocking the sequential activation of caspase-2 and -3, indicating the role of ROS in caspase-2-mediated apoptosis. Taken together, these results indicate that caspase-2 acts upstream of caspase-3 and that caspase-2 functions in response to DNA damage in both PhSe-T- and MeSe-T-induced apoptosis. Our results also suggest that ROS are critical regulators of the sequential activation of caspase-2 and -3 in nucleoside derivative-treated cancer cells.
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Massaoka MH, Matsuo AL, Figueiredo CR, Farias CF, Girola N, Arruda DC, Scutti JAB, Romoff P, Favero OA, Ferreira MJP, Lago JHG, Travassos LR. Jacaranone induces apoptosis in melanoma cells via ROS-mediated downregulation of Akt and p38 MAPK activation and displays antitumor activity in vivo. PLoS One 2012; 7:e38698. [PMID: 22701695 PMCID: PMC3368838 DOI: 10.1371/journal.pone.0038698] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 05/09/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Malignant melanoma is a deadly type of metastatic skin cancer with increased incidence over the past 30 years. Despite the advanced knowledge on the biology, immunobiology and molecular genetics of melanoma, the alternatives of treatment are limited with poor prognosis. On clinical trials, natural products and among them redox-active quinones have been tested in the attempt to control the growth of cancer cells. Recently, we isolated jacaranone from Pentacalia desiderabilis, a benzoquinone derivative that showed a broad antitumor activity and protective anti-melanoma effect in a syngeneic model. The purified substance is active at micromolar concentrations, is not hemolytic, and is not toxic in naïve mice. METHODOLOGY/PRINCIPAL FINDINGS The jacaranone antitumor activity was shown against several human cancer cell lines in vitro. Moreover, the induction of apoptosis in murine melanoma cells and jacaranone antitumor activity in vivo, in a melanoma experimental model, were also shown. Jacaranone renders antiproliferative and proapoptotic responses in tumor cells, by acting on Akt and p38 MAPK signaling pathways through generation of reactive oxygen species (ROS). The free radical scavenger N-acetyl-cysteine (NAC) was able to completely suppress cell death induced by jacaranone as it blocked Akt downregulation, p38 MAPK activation as well as upregulation of proapoptotic Bax. Notably, treatment of melanoma growing subcutaneously in mice with jacaranone significantly extended the mean survival times in a dose-dependent manner. CONCLUSIONS/SIGNIFICANCE The results provide evidence for the mechanisms of action of jacaranone and emphasize the potential use of this quinone for the treatment of melanoma.
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Affiliation(s)
- Mariana H. Massaoka
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Alisson L. Matsuo
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Carlos R. Figueiredo
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Camyla F. Farias
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Natália Girola
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Denise C. Arruda
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Jorge A. B. Scutti
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
| | - Paulete Romoff
- Centro de Ciências e Humanidades e Centro de Ciências Biológicas e da Saúde, Universidade Presbiteriana Mackenzie, São Paulo, São Paulo, Brazil
| | - Oriana A. Favero
- Centro de Ciências e Humanidades e Centro de Ciências Biológicas e da Saúde, Universidade Presbiteriana Mackenzie, São Paulo, São Paulo, Brazil
| | - Marcelo J. P. Ferreira
- Centro de Ciências e Humanidades e Centro de Ciências Biológicas e da Saúde, Universidade Presbiteriana Mackenzie, São Paulo, São Paulo, Brazil
| | - João H. G. Lago
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema, São Paulo, Brazil
| | - Luiz R. Travassos
- Unidade de Oncologia Experimental, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil
- * E-mail:
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Chan KM, Hamzah R, Rahaman AA, Jong VYM, Khong HY, Rajab NF, Ee GCL, Inayat-Hussain SH. The pyranoxanthone inophyllin A induces oxidative stress mediated-apoptosis in Jurkat T lymphoblastic leukemia cells. Food Chem Toxicol 2012; 50:2916-22. [PMID: 22613213 DOI: 10.1016/j.fct.2012.04.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 04/25/2012] [Accepted: 04/30/2012] [Indexed: 11/19/2022]
Abstract
Inophyllin A (INO-A), a pyranoxanthone isolated from the roots of Calophyllum inophyllum represents a new xanthone with potential chemotherapeutic activity. In this study, the molecular mechanism of INO-A-induced cell death was investigated in Jurkat T lymphoblastic leukemia cells. Assessment of phosphatidylserine exposure confirmed apoptosis as the primary mode of cell death in INO-A-treated Jurkat cells. INO-A treatment for only 30 min resulted in a significant increase of tail moment which suggests that DNA damage is an early apoptotic signal. Further flow cytometric assessment of the superoxide anion level confirmed that INO-A induced DNA damage was mediated with a concomitant generation of reactive oxygen species (ROS). Investigation on the thiols revealed an early decrease of free thiols in 30 min after 50 μM INO-A treatment. Using tetramethylrhodamine ethyl ester, a potentiometric dye, the loss of mitochondrial membrane potential (MPP) was observed in INO-A-treated cells as early as 30 min. The INO-A-induced apoptosis progressed with the simultaneous activation of caspases-2 and -9 which then led to the processing of caspase-3. Taken together, these data demonstrate that INO-A induced early oxidative stress, DNA damage and loss of MMP which subsequently led to the activation of an intrinsic pathway of apoptosis in Jurkat cells.
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Affiliation(s)
- Kok Meng Chan
- Toxicology Laboratory, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Wilayah Persekutuan, Malaysia.
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Fang YT, Lin CF, Wang CY, Anderson R, Lin YS. Interferon-γ stimulates p11-dependent surface expression of annexin A2 in lung epithelial cells to enhance phagocytosis. J Cell Physiol 2012; 227:2775-87. [DOI: 10.1002/jcp.23026] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Kim BM, Hong SH. Sequential caspase-2 and caspase-8 activation is essential for saikosaponin a-induced apoptosis of human colon carcinoma cell lines. Apoptosis 2011; 16:184-97. [PMID: 21107704 DOI: 10.1007/s10495-010-0557-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we investigated the signaling pathways implicated in SSa-induced apoptosis of human colon carcinoma (HCC) cell lines. SSa-induced apoptosis of HCC cells was associated with proteolytic activation of caspase-9, caspase-3, and PARP cleavages and decreased levels of IAP family members, such as XIAP and c-IAP-2, but not of survivin. The fluorescence intensity of DiOC6 was significantly reduced after SSa treatment. CsA significantly inhibited SSa-induced loss of mitochondrial transmembrane potential and moderately inhibited SSa-induced cell death. SSa treatment also enhanced the activities of caspase-2 and caspase-8, Bid cleavage, and the conformational activation of Bax. Additionally, SSa-induced apoptosis was inhibited by both the selective caspase-2 inhibitor z-VDVAD-fmk and the selective caspase-8 inhibitor z-IETD-fmk and also by si-RNAs against caspase-2 and caspase-8. The selective caspase-9 inhibitor, z-LEHD-fmk, also inhibited SSa-induced apoptosis, albeit to a lesser extent compared to z-VDVAD-fmk and z-IETD-fmk, indicating that both mitochondria-dependent and mitochondria-independent pathways are associated with SSa-induced apoptosis. Both z-VDVAD-fmk and z-IETD-fmk significantly attenuated the colony-inhibiting effect of SSa. Moreover, inhibition of caspase-2 activation by the pharmacological inhibitor z-VDVAD-fmk, or by knockdown of protein levels using a si-RNA, suppressed SSa-induced caspase-8 activation, Bid cleavage, and the conformational activation of Bax. Although caspase-8 is an initiator caspase like caspase-2, the inhibition of caspase-8 activation by knockdown using a si-RNA did not suppress SSa-induced caspase-2 activation. Altogether, our results suggest that sequential activation of caspase-2 and caspase-8 is a critical step in SSa-induced apoptosis.
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Affiliation(s)
- Byeong Mo Kim
- Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-Gu, Seoul 139-706, Korea
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Translocation and oligomerization of Bax is regulated independently by activation of p38 MAPK and caspase-2 during MN9D dopaminergic neurodegeneration. Apoptosis 2011; 16:1087-100. [DOI: 10.1007/s10495-011-0627-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Tamoxifen enhances therapeutic effects of gemcitabine on cholangiocarcinoma tumorigenesis. J Transl Med 2011; 91:896-904. [PMID: 21464824 DOI: 10.1038/labinvest.2011.60] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cholangiocarcinoma is a highly malignant tumor with limited therapeutic options. We have previously reported that tamoxifen (TMX) induces apoptosis of cholangiocarcinoma cells and reduces cholangiocarcinoma tumorigenesis in mice. In the present studies, we determined the effect of combination therapy of TMX and gemcitabine (GMT), another chemotherapeutical reagent for many cancers, on cholangiocarcinoma tumorigenesis and investigated the responsible mechanisms. GMT inhibited cell growth and induced apoptosis of cholangiocarcinoma cells in a concentration-dependent manner. TMX enhanced GMT-induced apoptosis of cholangiocarcinoma cells. Consistently, GMT (15 mg/kg) inhibited cholangiocarcinoma tumorigenesis in nude mice by 50%. TMX (15 mg/kg) enhanced the inhibitory effect of GMT on tumorigenesis by 33%. The inhibition of tumor growth correlated with enhanced apoptosis in tumor tissues. To elucidate the mechanisms underlying the additive effects of TMX on GMT-induced apoptosis, we determined the activation of caspases in cholangiocarcinoma cells exposed to GMT, TMX, or both. Activation of caspases 9 and 3, as well as cytochrome c release to the cytosol, was demonstrated in cells exposed to both reagents. In contrast, TMX activated caspase 2, whereas GMT had no effect. Inhibition of caspase 2 activation decreased TMX-, but not GMT-, induced activation of caspase 3 and apoptosis of cholangiocarcinoma cells. Similarly, activation of caspase 2 was found in tumors from TMX-treated mice, but not GMT-treated mice. Therefore, the enhanced effect of TMX on GMT-induced cholangiocarcinoma cell death is partially mediated by activation of caspase 2. TMX and GMT both induce apoptosis and inhibit cholangiocarcinoma tumorigenesis, which may be attributed to the activation of distinct apoptosis signals by TMX and GMT. Our studies provide in vivo evidence and molecular insight to support the use of TMX and GMT in combination as an effective therapy for cholangiocarcinoma.
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Shao ZH, Wojcik KR, Qin Y, Li CQ, Hoek TLV, Hamann KJ. Blockade of Caspase-2 Activity Inhibits Ischemia/Reperfusion-Induced Mitochondrial Reactive Oxygen Burst and Cell Death in Cardiomyocytes. J Cell Death 2011. [DOI: 10.4137/jcd.s6723] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We previously showed that initiator caspases-2 and −8 are prominently activated in ischemia/reperfusion (I/R)-induced injury in cardiomyocytes, but while blockade of caspase-2 activity enhanced cell survival, blockade of caspase-8 activity did not protect cardiomyocytes. Because apoptotic death in these cells is characterized by a burst of reactive oxygen species (ROS) at reperfusion and their survival by inhibition of this burst, we examined the effects of blocking caspase-2 and caspase-8 activities on ROS production. Caspase-2 inhibition blocked the reperfusion-induced ROS burst, while inhibition of caspase-8 did not. We also examined effects of caspase inhibition on mitochondrial membrane potential (ΔΨm) and mitochondrial function and found that blocking caspase-2, but not caspase-8, allowed recovery of ΔΨm and mitochondrial functionality. Furthermore, knockdown of caspase-2 by small-interfering (si)RNA confirmed caspase-2 participation in cytochrome c release, which correlates with loss of ΔΨm and cell death in these cardiomyocytes.
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Affiliation(s)
- Zuo-Hui Shao
- Emergency Medicine, Department of Medicine and The emergency resuscitation Center, The University of Chicago, Chicago, IL 60637, USA
| | | | - Yimin Qin
- Sections of Pulmonary and Critical Care Medicine
| | - Chang-Qing Li
- Emergency Medicine, Department of Medicine and The emergency resuscitation Center, The University of Chicago, Chicago, IL 60637, USA
| | - Terry L. Vanden Hoek
- Emergency Medicine, Department of Medicine and The emergency resuscitation Center, The University of Chicago, Chicago, IL 60637, USA
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Apoptotic sphingolipid ceramide in cancer therapy. J Lipids 2011; 2011:565316. [PMID: 21490804 PMCID: PMC3066853 DOI: 10.1155/2011/565316] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 10/26/2010] [Indexed: 11/18/2022] Open
Abstract
Apoptosis, also called programmed cell death, is physiologically and pathologically involved in cellular homeostasis. Escape of apoptotic signaling is a critical strategy commonly used for cancer tumorigenesis. Ceramide, a derivative of sphingolipid breakdown products, acts as second messenger for multiple extracellular stimuli including growth factors, chemical agents, and environmental stresses, such as hypoxia, and heat stress as well as irradiation. Also, ceramide acts as tumor-suppressor lipid because a variety of stress stimuli cause apoptosis by increasing intracellular ceramide to initiate apoptotic signaling. Defects on ceramide generation and sphingolipid metabolism are developed for cancer cell survival and cancer therapy resistance. Alternatively, targeting ceramide metabolism to correct these defects might provide opportunities to overcome cancer therapy resistance.
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Molecular characterization of apoptosis induced by CARF silencing in human cancer cells. Cell Death Differ 2010; 18:589-601. [PMID: 21052095 DOI: 10.1038/cdd.2010.129] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Collaborator of ARF (CARF) was cloned as an ARF-interacting protein and shown to regulate the p53-p21(WAF1)-HDM2 pathway, which is central to tumor suppression via senescence and apoptosis. We had previously reported that CARF inhibition in cancer cells led to polyploidy and caspase-dependent apoptosis, however, the mechanisms governing this phenomenon remained unknown. Thus, we examined various cell death and survival pathways including the mitochondrial stress, ataxia telangiectasia mutated (ATM)-ATR, Ras-MAP kinase and retinoblastoma cascades. We found that CARF is a pleiotropic regulator with widespread effects; its suppression affected all investigated pathways. Most remarkably, it protected the cells against genotoxicity; CARF knockdown elicited DNA damage response as evidenced by increased levels of phosphorylated ATM and γH2AX, leading to induction of mitotic arrest and eventual apoptosis. We also show that the CARF-silencing-induced apoptosis in vitro translates to in vivo. In a human tumor xenograft mouse model, treatment of developing tumors with short hairpin RNA (shRNA) against CARF via an adenovirus carrier induced complete suppression of tumor growth, suggesting that CARF shRNA is a strong candidate for an anticancer reagent. We demonstrate that CARF has a vital role in genome preservation and tumor suppression and CARF siRNA is an effective novel cancer therapeutic agent.
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Effect of loop structure of bovine lactoferricin on apoptosis in Jurkat cells. Biometals 2010; 23:555-61. [PMID: 20237822 DOI: 10.1007/s10534-010-9324-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Accepted: 03/03/2010] [Indexed: 10/19/2022]
Abstract
Bovine lactoferricin (LfcinB) is a cationic peptide that selectively induces apoptosis in Jurkat cells. However less is known about the influence of this kind of apoptosis on the intra-cellular ceramide metabolism and the structure-function relationship between the loop structure of LfcinB and its action of inducing apoptosis in Jurkat cells. In the present study, the artificially synthesized LfcinB and LfcinB-derived peptide (Cys 19 residue in LfcinB was replaced by Ala) was added in Jurkat cells, the nucleolus shape was observed by fluorescent microscopy, the ceramide concentration in Jurkat cells was determined by reversed phase high performance liquid chromatography (RP-HPLC). The results of MTT assay showed that LfcinB inhibited proliferation of Jurkat cells, and the inhibition rate was approximately 18.90%. Moreover, the inhibition rate of LfcinB together with MAPP was upto approximately 59.89%. The RP-HPLC result showed that LfcinB improved the ceramide level in Jurkat cells. By using the DNA fragmentation assay and observing the nucleolus shape, the result displayed deficiency of the loop structure could cause LfcinB losing the biological activity of inducing apoptosis in Jurkat cells.
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Das A, McDowell M, Pava MJ, Smith JA, Reiter RJ, Woodward JJ, Varma AK, Ray SK, Banik NL. The inhibition of apoptosis by melatonin in VSC4.1 motoneurons exposed to oxidative stress, glutamate excitotoxicity, or TNF-alpha toxicity involves membrane melatonin receptors. J Pineal Res 2010; 48:157-69. [PMID: 20082663 PMCID: PMC2862889 DOI: 10.1111/j.1600-079x.2009.00739.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Loss of motoneurons may underlie some of the deficits in motor function associated with the central nervous system (CNS) injuries and diseases. We tested whether melatonin, a potent antioxidant and free radical scavenger, would prevent motoneuron apoptosis following exposure to toxins and whether this neuroprotection is mediated by melatonin receptors. Exposure of VSC4.1 motoneurons to either 50 microm H(2)O(2), 25 microm glutamate (LGA), or 50 ng/mL tumor necrosis factor-alpha (TNF-alpha) for 24 h caused significant increases in apoptosis, as determined by Wright staining and ApopTag assay. Analyses of mRNA and proteins showed increased expression and activities of stress kinases and cysteine proteases and loss of mitochondrial membrane potential during apoptosis. These insults also caused increases in intracellular free [Ca(2+)] and activities of calpain and caspases. Cells exposed to stress stimuli for 15 min were then treated with 200 nm melatonin. Post-treatment of cells with melatonin attenuated production of reactive oxygen species (ROS) and phosphorylation of p38, MAPK, and JNK1, prevented cell death, and maintained whole-cell membrane potential, indicating functional neuroprotection. Melatonin receptors (MT1 and MT2) were upregulated following treatment with melatonin. To confirm the involvement of MT1 and MT2 in providing neuroprotection, cells were post-treated (20 min) with 10 microm luzindole (melatonin receptor antagonist). Luzindole significantly attenuated melatonin-induced neuroprotection, suggesting that melatonin worked, at least in part, via its receptors to prevent VSC4.1 motoneuron apoptosis. Results suggest that neuroprotection rendered by melatonin to motoneurons is receptor mediated and melatonin may be an effective neuroprotective agent to attenuate motoneuron death in CNS injuries and diseases.
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Affiliation(s)
- Arabinda Das
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
| | - Misty McDowell
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
| | - Matthew J Pava
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
| | | | - Russel J. Reiter
- Department of Cellular and Structural Biology, University of Texas, San Antonio, TX 78229, USA
| | - John J. Woodward
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
| | - Abhay K. Varma
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
| | - Swapan K. Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC 29209, USA
| | - Naren L. Banik
- Department of Neurosciences (Division of Neurology), Medical University of South Carolina, Charleston, SC 29425, USA
- Correspondence to: Naren L. Banik, Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC 29425. Phone: (843) 792-8570; Fax: (843) 792-8626; Naren L. Banik ()
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López-Royuela N, Pérez-Galán P, Galán-Malo P, Yuste VJ, Anel A, Susín SA, Naval J, Marzo I. Different contribution of BH3-only proteins and caspases to doxorubicin-induced apoptosis in p53-deficient leukemia cells. Biochem Pharmacol 2010; 79:1746-58. [PMID: 20188077 DOI: 10.1016/j.bcp.2010.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 02/15/2010] [Accepted: 02/16/2010] [Indexed: 12/29/2022]
Abstract
Bcl-2 family proteins are key regulators of the intrinsic apoptotic pathway, either facilitating (Bax, Bak, BH3-only) or inhibiting (Bcl-2, Bcl-x(L), Mcl-1, A1) mitochondrial release of apoptogenic factors. The role of caspases in this process is a matter of controversy. We have analyzed the relative contribution of caspases and Bcl-2 family of proteins in the induction phase of apoptosis triggered by doxorubicin in two p53-deficient leukemia cell lines, Jurkat and U937. First, we have found that caspases are dispensable for the induction phase of doxorubicin-induced apoptosis in both cell lines but they are needed to speed up the execution phase in Jurkat cells, not expressing Bax. Thus, down-regulation of Bak expression by siRNA significantly prevented doxorubicin-induced apoptosis in Jurkat but not in U937 cells. Reduction of Mcl-1 protein levels with siRNA increased sensitivity to apoptosis in both cell lines. Moreover, our results indicate that the contribution of BH3-only proteins to apoptosis is cell line specific. In Jurkat cells simultaneous silencing of Bim and PUMA was necessary to reduce doxorubicin-induced apoptosis. In U937 cells silencing of Bim or Noxa reduced sensitivity to doxorubicin. Immunoprecipitation experiments discarded an interaction between Mcl-1 and Bak in both cell lines and underscored the role of Bim and PUMA as mediators of Bax/Bak activation.
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Affiliation(s)
- Nuria López-Royuela
- Departamento de Bioquimica, Biologia Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
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Abstract
Aberrations in proteins that control apoptosis and cell survival are common in cancer. These aberrations often reside in signalling proteins that control the activation of the apoptotic machinery or in the Bcl-2 family of proteins that control caspase activation. Recent evidence suggests that caspase 2, one of the most evolutionarily conserved caspases, may have multiple roles in the DNA damage response, cell cycle regulation and tumour suppression. These findings are unexpected and have important implications for our understanding of tumorigenesis and the treatment of cancer.
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Affiliation(s)
- Sharad Kumar
- Centre for Cancer Biology, Department of Haematology, SA Pathology, Frome Road, Adelaide, SA5000, Australia.
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Cullen SP, Martin SJ. Caspase activation pathways: some recent progress. Cell Death Differ 2009; 16:935-8. [PMID: 19528949 DOI: 10.1038/cdd.2009.59] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Nijhuis EHA, Le Gac S, Poot AA, Feijen J, Vermes I. Bax-mediated mitochondrial membrane permeabilization after heat treatment is caspase-2 dependent. Int J Hyperthermia 2009; 24:357-65. [DOI: 10.1080/02656730801944914] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abstract
A hallmark of tissue injury in various models of ischemia/reperfusion (IR) is mitochondrial dysfunction and the release of mitochondrial proapoptotic proteins leading to cell death. Although IR-induced mitochondrial injury has been extensively studied and key mitochondrial functions affected by IR are chiefly characterized, the nature of the molecule that causes loss of mitochondrial integrity and function remains obscure. It has become increasingly clear that ceramide, a membrane sphingolipid and a key mediator of cell stress responses, could play a critical role in IR-induced mitochondrial damage. Emerging data point to excessive ceramide accumulation in tissue and, specifically, in mitochondria after IR. Exogenously added to isolated mitochondria, ceramide could mimic some of the mitochondrial dysfunctions occurring in IR. The recent identification and characterization of major enzymes in ceramide synthesis is expected to contribute to the understanding of molecular mechanisms of ceramide involvement in mitochondrial damage in IR. This review will examine the experimental evidence supporting the important role of ceramide in mitochondrial dysfunction in IR to highlight potential targets for pharmacological manipulation of ceramide levels.
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Ortiz RJ, Lizama C, Codelia VA, Moreno RD. A molecular evaluation of germ cell death induced by etoposide in pubertal rat testes. Mol Hum Reprod 2009; 15:363-71. [PMID: 19346530 DOI: 10.1093/molehr/gap024] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Etoposide is widely used in the treatment of patients with testicular cancer. The mechanism underlying apoptosis induction in cancer cells has been studied in different cell types, but it is not known whether the same factors participate in viable germ cells undergoing programmed cell death. Since testicular cancer primarily affects young males, we used pubertal rats (21 days old) as a model to determine different apoptotic parameters after etoposide treatment in healthy testes. We found that one intratesticular injection of etoposide (1.2 microg/testis) induced a significant increase in spermatocytes undergoing apoptosis, along with activation of caspase-9, -8 and -3 after 24 h of treatment. Spermatocyte apoptosis was inhibited when a general caspase inhibitor was added along with etoposide. Etoposide induces a significant stabilization/activation of p53, resulting in an increase level of this protein. The mRNA of Bcl-2 antagonist of cell death (BAD), a pro-apoptotic gene and a transcriptional target of p53, was significantly increased after etoposide treatment. Thus, our results suggest a single injection of etoposide induces apoptosis in healthy pachytene spermatocytes mediated by p53 and caspase activation. These findings will assist the search for new therapies to prevent the deleterious effect of cancer drugs upon normal cells.
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Affiliation(s)
- Rina J Ortiz
- Departamento de Ciencias Fisiológicas, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile
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Myung SJ, Yoon JH, Kim BH, Lee JH, Jung EU, Lee HS. Heat shock protein 90 inhibitor induces apoptosis and attenuates activation of hepatic stellate cells. J Pharmacol Exp Ther 2009; 330:276-82. [PMID: 19329756 DOI: 10.1124/jpet.109.151860] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Activated hepatic stellate cells (HSCs) are major participants in hepatic fibrosis; thus, the induction of HSC apoptosis has been proposed as an antifibrotic treatment strategy. Heat shock protein (Hsp) 90 is a molecular chaperone that stabilizes major signal transduction proteins, and its inhibitors have antitumor activity. In this study, the susceptibility of HSCs to an Hsp90 inhibitor was evaluated. LX-2 cells, an immortalized human HSC line, 17-(allylamino)-17-demethoxygeldanamycin (17AAG), an Hsp90 inhibitor, and monensin, an acidic sphingomyelinase inhibitor, were used in this study. Cellular apoptosis was quantified by 4',6-diamidino-2-phenylindole dihydrochloride staining, and signaling cascades were explored using immunoblotting and immunoprecipitation techniques. Nuclear factor (NF) kappaB activities were evaluated by immunofluorescent microscopy and enzyme-linked immunosorbent assay. Collagen alpha1 and alpha-smooth muscle actin expressions were determined by real-time reverse transcription-polymerase chain reaction and immunoblotting, respectively. It was found that 17AAG induced HSC apoptosis and that caspase 8 cleavage preceded the downstream activation of apoptotic signaling cascades. Furthermore, this caspase 8 activation was dependent on ceramide generation by acidic sphingomyelinase. In addition, 17AAG prevented NFkappaB nuclear translocation and activation, specifically by inducing complex formation between NFkappaB and the glucocorticoid receptor. In accordance, NFkappaB-dependent cellular FLICE-like inhibitory protein expression level was found to be reduced by 17AAG. Finally, 17AAG down-regulated collagen alpha1 and alpha-smooth muscle actin expression levels in HSCs before inducing apoptosis. These results demonstrate that the Hsp90 inhibitor induces HSC apoptosis via a sphingomyelinase- and NFkappaB-dependent mechanism. Because this inhibitor also reduces HSC activation before apoptosis, Hsp90 inhibitor treatment might be therapeutically useful as an antifibrotic strategy in a variety of liver diseases.
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Affiliation(s)
- Sun Jung Myung
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, 28 Yungun-dong, Chongno-gu, Seoul 110-744, Korea
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Schiffmann S, Sandner J, Schmidt R, Birod K, Wobst I, Schmidt H, Angioni C, Geisslinger G, Grösch S. The selective COX-2 inhibitor celecoxib modulates sphingolipid synthesis. J Lipid Res 2009; 50:32-40. [DOI: 10.1194/jlr.m800122-jlr200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Krumschnabel G, Sohm B, Bock F, Manzl C, Villunger A. The enigma of caspase-2: the laymen's view. Cell Death Differ 2008; 16:195-207. [PMID: 19023332 DOI: 10.1038/cdd.2008.170] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Proteolysis of cellular substrates by caspases (cysteine-dependent aspartate-specific proteases) is one of the hallmarks of apoptotic cell death. Although the activation of apoptotic caspases is considered a 'late-stage' event in apoptosis signaling, past the commitment stage, one caspase family member, caspase-2, splits the cell death community into half - those searching for evidence of an apical initiator function of this molecule and those considering it as an amplifier of the apoptotic caspase cascade, at best, if relevant for apoptosis at all. This review screens past and present biochemical as well as genetic evidence for caspase-2 function in cell death signaling and beyond.
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Affiliation(s)
- G Krumschnabel
- Division of Developmental Immunology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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