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Zhou XZ, Huang P, Wu YK, Yu JB, Sun J. Autophagy in benign prostatic hyperplasia: insights and therapeutic potential. BMC Urol 2024; 24:198. [PMID: 39261818 PMCID: PMC11391623 DOI: 10.1186/s12894-024-01585-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 08/30/2024] [Indexed: 09/13/2024] Open
Abstract
Autophagy is a cellular homeostatic mechanism characterized by cyclic degradation. It plays an essential role in maintaining cellular quality and survival by eliminating dysfunctional cellular components. This process is pivotal in various pathophysiological processes. Benign prostatic hyperplasia (BPH) is a common urological disorder in middle-aged and elderly men. It frequently presents as lower urinary tract symptoms due to an increase in epithelial and stromal cells surrounding the prostatic urethra. The precise pathogenesis of BPH is complex. In recent years, research on autophagy in BPH has gained significant momentum, with accumulating evidence indicating its crucial role in the onset and progression of the disease. This review aims to outline the various roles of autophagy in BPH and elucidate potential therapeutic strategies targeting autophagy for managing BPH.
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Affiliation(s)
- Xian-Zhao Zhou
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Pei Huang
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Yao-Kan Wu
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Jin-Ben Yu
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Jie Sun
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China.
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2
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Castillo Bautista CM, Eismann K, Gentzel M, Pelucchi S, Mertens J, Walters HE, Yun MH, Sterneckert J. Obatoclax Rescues FUS-ALS Phenotypes in iPSC-Derived Neurons by Inducing Autophagy. Cells 2023; 12:2247. [PMID: 37759469 PMCID: PMC10527391 DOI: 10.3390/cells12182247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/08/2023] [Accepted: 09/09/2023] [Indexed: 09/29/2023] Open
Abstract
Aging is associated with the disruption of protein homeostasis and causally contributes to multiple diseases, including amyotrophic lateral sclerosis (ALS). One strategy for restoring protein homeostasis and protecting neurons against age-dependent diseases such as ALS is to de-repress autophagy. BECN1 is a master regulator of autophagy; however, is repressed by BCL2 via a BH3 domain-mediated interaction. We used an induced pluripotent stem cell model of ALS caused by mutant FUS to identify a small molecule BH3 mimetic that disrupts the BECN1-BCL2 interaction. We identified obatoclax as a brain-penetrant drug candidate that rescued neurons at nanomolar concentrations by reducing cytoplasmic FUS levels, restoring protein homeostasis, and reducing degeneration. Proteomics data suggest that obatoclax protects neurons via multiple mechanisms. Thus, obatoclax is a candidate for repurposing as a possible ALS therapeutic and, potentially, for other age-associated disorders linked to defects in protein homeostasis.
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Affiliation(s)
| | - Kristin Eismann
- Core Facility Mass Spectrometry & Proteomics, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany (M.G.)
| | - Marc Gentzel
- Core Facility Mass Spectrometry & Proteomics, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany (M.G.)
| | - Silvia Pelucchi
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92161, USA (J.M.)
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20133 Milan, Italy
| | - Jerome Mertens
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92161, USA (J.M.)
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Institute for Molecular Biology, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Hannah E. Walters
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (C.M.C.B.); (H.E.W.)
| | - Maximina H. Yun
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (C.M.C.B.); (H.E.W.)
- Max Planck Institute for Molecular Cell Biology and Genetics, 01307 Dresden, Germany
- Cluster of Excellence Physics of Life, Technische Universität Dresden, 01307 Dresden, Germany
| | - Jared Sterneckert
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (C.M.C.B.); (H.E.W.)
- Medical Faculty Carl Gustav Carus of TU Dresden, 01307 Dresden, Germany
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3
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Popli P, Tang S, Chadchan SB, Talwar C, Rucker EB, Guan X, Monsivais D, Lydon JP, Stallings CL, Moley KH, Kommagani R. Beclin-1-dependent autophagy, but not apoptosis, is critical for stem-cell-mediated endometrial programming and the establishment of pregnancy. Dev Cell 2023; 58:885-897.e4. [PMID: 37040770 PMCID: PMC10289806 DOI: 10.1016/j.devcel.2023.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/31/2023] [Accepted: 03/16/2023] [Indexed: 04/13/2023]
Abstract
The human endometrium shows a remarkable regenerative capacity that enables cyclical regeneration and remodeling throughout a woman's reproductive life. Although early postnatal uterine developmental cues direct this regeneration, the vital factors that govern early endometrial programming are largely unknown. We report that Beclin-1, an essential autophagy-associated protein, plays an integral role in uterine morphogenesis during the early postnatal period. We show that conditional depletion of Beclin-1 in the uterus triggers apoptosis and causes progressive loss of Lgr5+/Aldh1a1+ endometrial progenitor stem cells, with concomitant loss of Wnt signaling, which is crucial for stem cell renewal and epithelial gland development. Beclin-1 knockin (Becn1 KI) mice with disabled apoptosis exhibit normal uterine development. Importantly, the restoration of Beclin-1-driven autophagy, but not apoptosis, promotes normal uterine adenogenesis and morphogenesis. Together, the data suggest that Beclin-1-mediated autophagy acts as a molecular switch that governs the early uterine morphogenetic program by maintaining the endometrial progenitor stem cells.
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Affiliation(s)
- Pooja Popli
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Suni Tang
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Sangappa B Chadchan
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Chandni Talwar
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Edmund B Rucker
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Xiaoming Guan
- Department of Obstetrics and Gynecology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Diana Monsivais
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - John P Lydon
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Christina L Stallings
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Women's Infectious Disease Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kelle H Moley
- Department Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Reproductive Health Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ramakrishna Kommagani
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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4
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Okusha Y, Murshid A, Calderwood SK. Proteotoxic stress-induced autophagy is regulated by the NRF2 pathway via extracellular vesicles. Cell Stress Chaperones 2023; 28:167-175. [PMID: 36773174 PMCID: PMC10050656 DOI: 10.1007/s12192-023-01326-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/17/2023] [Accepted: 01/24/2023] [Indexed: 02/12/2023] Open
Abstract
Protein homeostasis involves a number of overlapping mechanisms, including the autophagy program, that can lead to the resolution of protein damage. We aimed in this study to examine mechanisms of autophagy in the proteotoxic stress response. We found that such stress results in a rapid elevation in the rate of autophagy in mammalian cells. Induction of this process occurred coincidentally with the increased release of extracellular vesicles (EVs) into the extracellular microenvironment. We next found that purified EVs that had been released from stressed cells were capable of directly increasing autophagic flux in recipient cells. The EVs contained a range of cargo proteins, including HSP70, BAG3, and activated transcription factor phospho-NRF2 (pNRF2). NRF2 regulates the activation of both the oxidative stress response and autophagy genes. Both heat shock and exposure of cells to proteotoxic stress-induced EVs increased the intracellular levels of pNRF2 in cells. Heat shock-induced proteotoxicity also led to increases in the levels of proteins in the oxidative stress response, including HO-1 and NQO1, as well as the key autophagy proteins LC3, ATG5, and ATG7, known to be regulated by NRF2. Increases in these autophagy proteins were dependent on the expression of NRF2 and were ablated by NRF2 knockdown.
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Affiliation(s)
- Yuka Okusha
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, East Campus DA-717A, Boston, MA, 02215, USA.
- JSPS Overseas research Fellow, Tokyo, Japan.
| | - Ayesha Murshid
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, East Campus DA-717A, Boston, MA, 02215, USA
| | - Stuart K Calderwood
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, East Campus DA-717A, Boston, MA, 02215, USA.
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5
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Deng R, Jiang K, Chen F, Miao Y, Lu Y, Su F, Liang J, Qian J, Wang D, Xiang Y, Shen L. Novel cardioprotective mechanism for Empagliflozin in nondiabetic myocardial infarction with acute hyperglycemia. Biomed Pharmacother 2022; 154:113606. [PMID: 36030589 DOI: 10.1016/j.biopha.2022.113606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/20/2022] [Accepted: 08/23/2022] [Indexed: 01/08/2023] Open
Abstract
Patients with AMI and hyperglycemia upon hospital admission exhibited poorer prognosis compared with those without hyperglycemia. It is unknown whether SGLT2 inhibitors can also improve nondiabetic myocardial infarction (MI) with acute hyperglycemia and the underlying mechanisms. Here we demonstrated that hyperglycemia patients were more likely to have worse cardiac function levels, such as with Killip III/IV during hospitalization. Glucose injection-induced nondiabetic MI accompanied by acute hyperglycemia in WT mice, manifested lower survival compared with control. A significant increase in both survival and LV function was observed when treated with empagliflozin (EMPA). In addition, EMPA attenuated fibrosis and autophagy of border cardiac tissue in mice with MI accompanied by acute hyperglycemia. Applying Beclin1+/- and NHE1 cKO mice, we found that Beclin1 deficiency improved survival. Mechanistically, EMPA had a more significant cardioprotective effect through inhibited its autophagy level by targeted Beclin1 rather than NHE1. In addition, EMPA rescued cardiomyocytes autosis induced by Tat-beclin1 or GD, conferring cardioprotection decreasing autophagic cell death. These findings provide new insights that SGLT2 inhibitor effectively ameliorates the myocardial injury in nondiabetic myocardial infarction with acute hyperglycemia through suppressing beclin1-dependent autosis rather than elusively targeting NHE1 in cardiomyocytes.
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Affiliation(s)
- Ruhua Deng
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Kai Jiang
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Feng Chen
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Yutong Miao
- Department of Cardiology, Clinical Research Unit, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Yanqiao Lu
- Department of Cardiology, Clinical Research Unit, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Fanghua Su
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Jiayi Liang
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
| | - Jie Qian
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Dandan Wang
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Yaozu Xiang
- Shanghai East Hospital, Key Laboratory of Arrhythmias of the Ministrcy of Education of China, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China.
| | - Lan Shen
- Department of Cardiology, Clinical Research Unit, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China.
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6
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Abramyan J, Geetha-Loganathan P, Šulcová M, Buchtová M. Role of Cell Death in Cellular Processes During Odontogenesis. Front Cell Dev Biol 2021; 9:671475. [PMID: 34222243 PMCID: PMC8250436 DOI: 10.3389/fcell.2021.671475] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/24/2021] [Indexed: 01/20/2023] Open
Abstract
The development of a tooth germ in a precise size, shape, and position in the jaw, involves meticulous regulation of cell proliferation and cell death. Apoptosis, as the most common type of programmed cell death during embryonic development, plays a number of key roles during odontogenesis, ranging from the budding of the oral epithelium during tooth initiation, to later tooth germ morphogenesis and removal of enamel knot signaling center. Here, we summarize recent knowledge about the distribution and function of apoptotic cells during odontogenesis in several vertebrate lineages, with a special focus on amniotes (mammals and reptiles). We discuss the regulatory roles that apoptosis plays on various cellular processes during odontogenesis. We also review apoptosis-associated molecular signaling during tooth development, including its relationship with the autophagic pathway. Lastly, we cover apoptotic pathway disruption, and alterations in apoptotic cell distribution in transgenic mouse models. These studies foster a deeper understanding how apoptotic cells affect cellular processes during normal odontogenesis, and how they contribute to dental disorders, which could lead to new avenues of treatment in the future.
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Affiliation(s)
- John Abramyan
- Department of Natural Sciences, University of Michigan–Dearborn, Dearborn, MI, United States
| | | | - Marie Šulcová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
- Laboratory of Molecular Morphogenesis, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Brno, Czechia
| | - Marcela Buchtová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
- Laboratory of Molecular Morphogenesis, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Brno, Czechia
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7
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Jin Y, Ji Y, Song Y, Choe SS, Jeon YG, Na H, Nam TW, Kim HJ, Nahmgoong H, Kim SM, Kim JW, Nam KT, Seong JK, Hwang D, Park CB, Lee IH, Kim JB, Lee HW. Depletion of Adipocyte Becn1 Leads to Lipodystrophy and Metabolic Dysregulation. Diabetes 2021; 70:182-195. [PMID: 33046512 PMCID: PMC7881852 DOI: 10.2337/db19-1239] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 10/02/2020] [Indexed: 11/13/2022]
Abstract
Becn1/Beclin-1 is a core component of the class III phosphatidylinositol 3-kinase required for autophagosome formation and vesicular trafficking. Although Becn1 has been implicated in numerous diseases such as cancer, aging, and neurodegenerative disease, the role of Becn1 in white adipose tissue and related metabolic diseases remains elusive. In this study, we show that adipocyte-specific Becn1 knockout mice develop severe lipodystrophy, leading to adipose tissue inflammation, hepatic steatosis, and insulin resistance. Ablation of Becn1 in adipocytes stimulates programmed cell death in a cell-autonomous manner, accompanied by elevated endoplasmic reticulum (ER) stress gene expression. Furthermore, we observed that Becn1 depletion sensitized mature adipocytes to ER stress, leading to accelerated cell death. Taken together, these data suggest that adipocyte Becn1 would serve as a crucial player for adipocyte survival and adipose tissue homeostasis.
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Affiliation(s)
- Young Jin
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Yul Ji
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Yaechan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Sung Sik Choe
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Yong Geun Jeon
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Heeju Na
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Tae Wook Nam
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Hye Jeong Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Hahn Nahmgoong
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Sung Min Kim
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Jae-Woo Kim
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Ki Taek Nam
- Severance Biomedical Science Institute, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Je Kyung Seong
- Korea Mouse Phenotyping Center, Seoul National University, Seoul, Republic of Korea
| | - Daehee Hwang
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Chan Bae Park
- Department of Physiology, Ajou University School of Medicine, Suwon, Republic of Korea
| | - In Hye Lee
- Department of Life Sciences, Ewha Womans University, Seoul, Republic of Korea
| | - Jae Bum Kim
- Department of Biological Sciences, Center for Adipocyte Structure-Function, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Han-Woong Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
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8
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The crosstalk between autophagy and apoptosis was mediated by phosphorylation of Bcl-2 and beclin1 in benzene-induced hematotoxicity. Cell Death Dis 2019; 10:772. [PMID: 31601785 PMCID: PMC6787223 DOI: 10.1038/s41419-019-2004-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 09/16/2019] [Accepted: 09/19/2019] [Indexed: 01/07/2023]
Abstract
Increasing evidence suggested that benzene exposure resulted in different types of hematological cancer. Both autophagy and apoptosis were reported to play vital roles in benzene toxicity, but the relationship between autophagy and apoptosis remain unclear in benzene-induced hematotoxicity. In this study, the toxic effect of benzene on autophagy and apoptosis in benzene-exposed workers and in vitro were verified. Results showed that benzene metabolite (1, 4-benzoquinone, 1, 4-BQ) dose-dependently induced autophagy and apoptosis via enhancing phosphorylation of Bcl-2 and beclin1. Finally, we also found that the elevated ROS was in line with enhancing the phosphorylation of Bcl-2 and beclin1 which contributed to 1, 4-BQ-induced autophagy and apoptosis. Taken together, this study for the first time found that the effect of 1, 4-BQ on the crosstalk between autophagy and apoptosis were modulated by the ROS generation via enhancing phosphorylation of Bcl-2(Ser70) and phosphorylation of beclin1(Thr119), which offered a novel insight into underlying molecular mechanisms of benzene-induced hematotoxicity, and specifically how the crosstalk between autophagy and apoptosis was involved in benzene toxicity. This work provided novel evidence for the toxic effects and risk assessment of benzene.
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9
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Jin Y, You L, Kim HJ, Lee HW. Telomerase Reverse Transcriptase Contains a BH3-Like Motif and Interacts with BCL-2 Family Members. Mol Cells 2018; 41:684-694. [PMID: 29937479 PMCID: PMC6078858 DOI: 10.14348/molcells.2018.0206] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 05/21/2018] [Indexed: 12/12/2022] Open
Abstract
Upregulation of human telomerase reverse transcriptase (hTERT) expression is an important factor in the cellular survival and cancer. Although growing evidence suggests that hTERT inhibits cellular apoptosis by telomere-independent functions, the mechanisms involved are not fully understood. Here, we show that hTERT contains a BH3-like motif, a short peptide sequence found in BCL-2 family proteins, and interacts with anti-apoptotic BCL-2 family proteins MCL-1 and BCL-xL, suggesting a functional link between hTERT and the mitochondrial pathway of apoptosis. Additionally, we propose that hTERT can be categorized into the atypical BH3-only proteins that promote cellular survival, possibly due to the non-canonical interaction between hTERT and antiapoptotic proteins. Although the detailed mechanisms underlying the hTERT BH3-like motif functions and interactions between hTERT and BCL-2 family proteins have not been elucidated, this work proposes a possible connection between hTERT and BCL-2 family members and reconsiders the role of the BH3-like motif as an interaction motif.
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Affiliation(s)
- Young Jin
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
| | - Long You
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
| | - Hye Jeong Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
| | - Han-Woong Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
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10
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Lin XL, Xiao WJ, Xiao LL, Liu MH. Molecular mechanisms of autophagy in cardiac ischemia/reperfusion injury (Review). Mol Med Rep 2018; 18:675-683. [PMID: 29845269 DOI: 10.3892/mmr.2018.9028] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 05/10/2018] [Indexed: 11/05/2022] Open
Abstract
Autophagy is a maintenance process for recycling long-lived proteins and cytoplasmic organelles. The level of this process is enhanced during ischemia/reperfusion (I/R) injury. Autophagy can trigger survival signaling in myocardial ischemia, whereas defective autophagy during reperfusion is detrimental. Autophagy can be regulated through multiple signaling pathways in I/R, including Beclin‑1/class III phosphatidylinositol‑3 kinase (PI‑3K), adenosine monophosphate activated protein kinase/mammalian target of rapamycin (mTOR), and PI‑3K/protein kinase B/mTOR pathways, which consequently lead to different functions. Thus, autophagy has both protective and detrimental functions, which are determined by different signaling pathways and conditions. Targeting the activation of autophagy can be a promising new therapeutic strategy for treating cardiovascular disease.
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Affiliation(s)
- Xiao-Long Lin
- Department of Pathology, Hui Zhou Third People's Hospital, Guangzhou Medical University, Huizhou, Guangdong 516002, P.R. China
| | - Wei-Jin Xiao
- Department of Pathology, The Central Hospital of Shaoyang, Hunan 422000, P.R. China
| | - Le-Le Xiao
- School of Medicine, Huzhou University, Huzhou, Zhejiang 313000, P.R. China
| | - Mi-Hua Liu
- Department of Infectious Diseases, Centre for Lipid Research and Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, P.R. China
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11
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Liu RF, Fu G, Li J, Yang YF, Wang XG, Bai PD, Chen YD. Roles of autophagy in androgen-induced benign prostatic hyperplasia in castrated rats. Exp Ther Med 2018; 15:2703-2710. [PMID: 29456672 PMCID: PMC5795549 DOI: 10.3892/etm.2018.5772] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 03/31/2017] [Indexed: 12/12/2022] Open
Abstract
The present study investigated the role of androgen in the process of androgen-induced prostate hyperplasia in castrated rats and assessed the role of the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/Akt/mTOR) pathway in this process. Furthermore, the extent to which autophagy may affect the level of androgen-induced benign prostatic hyperplasia was also explored. A total of 40 Sprague Dawley rats were randomly divided into four groups: Testosterone group, rapamycin group, 3-methyladenine (3-MA) group, and control group. The extent of hyperplasia in prostate tissue the apoptosis and autophagy were assayed. The prostate wet weight, volume and index in the testosterone group were significantly higher compared with the control group (P<0.05) and these factors were significantly lower in the rapamycin group compared with the testosterone group (P<0.05). HE staining demonstrated that prostate hyperplasia was obvious in the testosterone group. Western blotting revealed that caspase-3 levels were higher in the 3-MA group compared with the control group and Bcl-2 was higher in the testosterone group compared with the control group (P<0.05). Furthermore, in the rapamycin group, Bcl-2 protein expression levels were significantly lower than those in the testosterone group (P<0.05). The prostate tissue was analyzed using electron microscopy and autophagy bodies were identified in the rapamycin group. In the process of androgen-induced prostatic hyperplasia in castrated rats, the role of androgen may be related to the PI3K/Akt/mTOR signaling pathway. Rapamycin was able to inhibit the effect of testosterone and promoted prostate tissue hyperplasia by inhibiting the PI3K/Akt pathway. In addition to inhibiting apoptosis in prostate cells, androgen was able to induce rat prostate hyperplasia and may also be related to the promotion of the proliferation of prostate cells.
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Affiliation(s)
- Rong-Fu Liu
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Guo Fu
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Jian Li
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Yu-Feng Yang
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Xue-Gang Wang
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Pei-De Bai
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Yue-Dong Chen
- Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian 361003, P.R. China
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12
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O'Farrill JS, Gordon N. Autophagy in osteosarcoma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 804:147-60. [PMID: 24924173 DOI: 10.1007/978-3-319-04843-7_8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Osteosarcoma (OS) metastatic disease is resistant to conventional chemotherapy. Tumor resistance to chemotherapy has been one of the major areas of concern to clinicians and the topic of many laboratory investigators. Evaluation of mechanisms implicated in OS lung metastasis resistance to chemotherapy has been the focus of some of our most recent work. We have previously demonstrated the therapeutic efficacy of aerosol gemcitabine (GCB) in OS lung metastases. However, a subset of cells fails to respond to GCB treatment and persists as isolated lung metastases in vivo. Autophagy, a physiological mechanism that supports nutritional deprivation under stressful conditions, has been implicated in tumor resistance to chemotherapy. We demonstrated the induction of autophagy by GCB in LM7 metastatic human OS cells and K7M3 metastatic murine OS cells. Inhibition of autophagy resulted in increased sensitivity to GCB in LM7 cells. By contrast, inhibiting autophagy in K7M3 cells decreased GCB sensitivity. Defining the role autophagy plays in chemotherapy response in different tumor types has become of greater importance in order to identify the best suitable therapeutic approach. In this chapter, we summarize some of the most recent work related to autophagy in OS, identify some of the known mechanisms, and address the different roles autophagy plays in chemotherapy response.
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Affiliation(s)
- Janice Santiago O'Farrill
- Department of Pediatrics-Research, The Children's Cancer Hospital, University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA
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13
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Rubinstein AD, Kimchi A. Life in the balance - a mechanistic view of the crosstalk between autophagy and apoptosis. J Cell Sci 2013; 125:5259-68. [PMID: 23377657 DOI: 10.1242/jcs.115865] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cellular stress triggers a fascinating decision-making process in cells; they can either attempt to survive until the stress is resolved through the activation of cytoprotective pathways, such as autophagy, or can commit suicide by apoptosis in order to prevent further damage to surrounding healthy cells. Although autophagy and apoptosis constitute distinct cellular processes with often opposing outcomes, their signalling pathways are extensively interconnected through various mechanisms of crosstalk. The physiological relevance of the autophagy-apoptosis crosstalk is not well understood, but it is presumed to facilitate a controlled and well-balanced cellular response to a given stress signal. In this Commentary, we explore the various mechanisms by which autophagy and apoptosis regulate each other, and define general paradigms of crosstalk on the basis of mechanistic features. One paradigm relates to physical and functional interactions between pairs of specific apoptotic and autophagic proteins. In a second mechanistic paradigm, the apoptosis or autophagy processes (as opposed to individual proteins) regulate each other through induced caspase and autolysosomal activity, respectively. In a third paradigm unique to autophagy, caspases are recruited and activated on autophagosomal membranes. These mechanistic paradigms are discernible experimentally, and can therefore be used as a practical guide for the interpretation of experimental data.
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Affiliation(s)
- Assaf D Rubinstein
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100 Israel
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14
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Deegan S, Saveljeva S, Gorman AM, Samali A. Stress-induced self-cannibalism: on the regulation of autophagy by endoplasmic reticulum stress. Cell Mol Life Sci 2013; 70:2425-41. [PMID: 23052213 PMCID: PMC11113399 DOI: 10.1007/s00018-012-1173-4] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 09/06/2012] [Accepted: 09/17/2012] [Indexed: 12/26/2022]
Abstract
Macroautophagy (autophagy) is a cellular catabolic process which can be described as a self-cannibalism. It serves as an essential protective response during conditions of endoplasmic reticulum (ER) stress through the bulk removal and degradation of unfolded proteins and damaged organelles; in particular, mitochondria (mitophagy) and ER (reticulophagy). Autophagy is genetically regulated and the autophagic machinery facilitates removal of damaged cell components and proteins; however, if the cell stress is acute or irreversible, cell death ensues. Despite these advances in the field, very little is known about how autophagy is initiated and how the autophagy machinery is transcriptionally regulated in response to ER stress. Some three dozen autophagy genes have been shown to be required for the correct assembly and function of the autophagic machinery; however; very little is known about how these genes are regulated by cellular stress. Here, we will review current knowledge regarding how ER stress and the unfolded protein response (UPR) induce autophagy, including description of the different autophagy-related genes which are regulated by the UPR.
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Affiliation(s)
- Shane Deegan
- Apoptosis Research Centre, NUI Galway, Galway, Ireland
- School of Natural Sciences, NUI Galway, Galway, Ireland
| | - Svetlana Saveljeva
- Apoptosis Research Centre, NUI Galway, Galway, Ireland
- School of Natural Sciences, NUI Galway, Galway, Ireland
| | - Adrienne M. Gorman
- Apoptosis Research Centre, NUI Galway, Galway, Ireland
- School of Natural Sciences, NUI Galway, Galway, Ireland
| | - Afshin Samali
- Apoptosis Research Centre, NUI Galway, Galway, Ireland
- School of Natural Sciences, NUI Galway, Galway, Ireland
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15
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Lionaki E, Markaki M, Tavernarakis N. Autophagy and ageing: insights from invertebrate model organisms. Ageing Res Rev 2013; 12:413-28. [PMID: 22634332 DOI: 10.1016/j.arr.2012.05.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 05/03/2012] [Accepted: 05/08/2012] [Indexed: 12/11/2022]
Abstract
Ageing in diverse species ranging from yeast to humans is associated with the gradual, lifelong accumulation of molecular and cellular damage. Autophagy, a conserved lysosomal, self-destructive process involved in protein and organelle degradation, plays an essential role in both cellular and whole-animal homeostasis. Accumulating evidence now indicates that autophagic degradation declines with age and this gradual reduction of autophagy might have a causative role in the functional deterioration of biological systems during ageing. Indeed, loss of autophagy gene function significantly influences longevity. Moreover, genetic or pharmacological manipulations that extend lifespan in model organisms often activate autophagy. Interestingly, conserved signalling pathways and environmental factors that regulate ageing, such as the insulin/IGF-1 signalling pathway and oxidative stress response pathways converge on autophagy. In this article, we survey recent findings in invertebrates that contribute to advance our understanding of the molecular links between autophagy and the regulation of ageing. In addition, we consider related mechanisms in other organisms and discuss their similarities and idiosyncratic features in a comparative manner.
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16
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The autophagy protein Atg12 associates with antiapoptotic Bcl-2 family members to promote mitochondrial apoptosis. Mol Cell 2012; 44:698-709. [PMID: 22152474 DOI: 10.1016/j.molcel.2011.10.014] [Citation(s) in RCA: 208] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 09/07/2011] [Accepted: 10/10/2011] [Indexed: 01/22/2023]
Abstract
Autophagy and apoptosis constitute important determinants of cell fate and engage in a complex interplay in both physiological and pathological settings. The molecular basis of this crosstalk is poorly understood and relies, in part, on "dual-function" proteins that operate in both processes. Here, we identify the essential autophagy protein Atg12 as a positive mediator of mitochondrial apoptosis and show that Atg12 directly regulates the apoptotic pathway by binding and inactivating prosurvival Bcl-2 family members, including Bcl-2 and Mcl-1. The binding occurs independently of Atg5 or Atg3 and requires a unique BH3-like motif in Atg12, characterized by interaction studies and computational docking. In apoptotic cells, knockdown of Atg12 inhibited Bax activation and cytochrome c release, while ectopic expression of Atg12 antagonized the antiapoptotic activity of Mcl-1. The interaction between Atg12 and Bcl-2 family members may thus constitute an important point of convergence between autophagy and apoptosis in response to specific signals.
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17
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Zhang Y, Calderwood SK. Autophagy, protein aggregation and hyperthermia: a mini-review. Int J Hyperthermia 2011; 27:409-14. [PMID: 21756038 DOI: 10.3109/02656736.2011.552087] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE We aim to explore the role of macroautophagy in cellular responses to hyperthermia. Protein damage incurred during hyperthermia can either lead to cell death or may be repaired by polypeptide quality control pathways including: (1) the deterrence of protein unfolding by molecular chaperones and (2) proteolysis of the denatured proteins within the proteasome. A third pathway of protein quality control is triggered by formation of protein aggregates in the heat shocked cell. This is the macroautophagy pathway in which protein aggregates are transported to specialised organelles called autolysosomes capable of degrading the aggregates. The consequences for cell viability of triggering this pathway are complex and may involve cell death, although under many circumstances, including exposure of cells to hyperthermia, autophagy leads to enhanced cell survival. We have discussed mechanisms by which cells detect protein aggregates and recruit them into the macroautophagy pathway as well as the potential role of inhibiting this process in hyperthermia. CONCLUSIONS Directed macroautophagy, with its key role in protein quality control, seems an attractive target for a therapy such as hyperthermia that functions principally through denaturing the proteome. However, much work is needed to decode the mechanisms of thermal stress-mediated macroautophagy and their role in survival/death of cancer cells before recommendations can be made on targeting this pathway in combination with hyperthermia.
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Affiliation(s)
- Yue Zhang
- Molecular and Cellular Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School , 99 Brookline Avenue, Boston, MA 02215 , USA
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18
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Caspase-mediated cleavage of Beclin-1 inactivates Beclin-1-induced autophagy and enhances apoptosis by promoting the release of proapoptotic factors from mitochondria. Cell Death Dis 2011; 1:e18. [PMID: 21364619 PMCID: PMC3032505 DOI: 10.1038/cddis.2009.16] [Citation(s) in RCA: 502] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Autophagy and apoptosis are two important and interconnected stress-response mechanisms. However, the molecular interplay between these two pathways is not fully understood. To study the fate and function of autophagic proteins at the onset of apoptosis, we used a cellular model system in which autophagy precedes apoptosis. IL-3 depletion of Ba/F3 cells caused caspase (casp)-mediated cleavage of Beclin-1 and PI3KC3, two crucial components of the autophagy-inducing complex. We identified two casp cleavage sites in Beclin-1, TDVD133 and DQLD149, cleavage at which yields fragments lacking the autophagy-inducing capacity. Noteworthy, the C-terminal fragment, Beclin-1-C, localized predominantly at the mitochondria and sensitized the cells to apoptosis. Moreover, on isolated mitochondria, recombinant Beclin-1-C was able to induce the release of proapoptotic factors. These findings point to a mechanism by which casp-dependent generation of Beclin-1-C creates an amplifying loop enhancing apoptosis upon growth factor withdrawal.
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19
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Morselli E, Galluzzi L, Kepp O, Mariño G, Michaud M, Vitale I, Maiuri MC, Kroemer G. Oncosuppressive functions of autophagy. Antioxid Redox Signal 2011; 14:2251-69. [PMID: 20712403 DOI: 10.1089/ars.2010.3478] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Macroautophagy (herein referred to as autophagy) constitutes a phylogenetically old mechanism leading to the lysosomal degradation of cytoplasmic structures. At baseline levels, autophagy exerts homeostatic functions by ensuring the turnover of potentially harmful organelles and long-lived aggregate-prone proteins. Moreover, the autophagic flow can be dramatically upregulated in response to a plethora of stressful conditions, including glucose, amino acid, oxygen, or growth factor deprivation, accumulation of unfolded proteins in the endoplasmic reticulum, and invasion by intracellular pathogens. In some experimental settings, stress-induced autophagy has been shown to contribute to programmed cell death. Nevertheless, autophagy most often confers cytoprotection by providing cells with new metabolic substrates or by ridding them of noxious intracellular entities including protein aggregates and invading organisms. Thus, autophagy has been implicated in an ever-increasing number of human diseases including cancer. Autophagy inhibition accelerates the demise of tumor cells that are subjected to chemo- or radiotherapy, thereby constituting an interesting target for the development of anticancer strategies. However, several oncosuppressor proteins and oncoproteins have been recently shown to stimulate and inhibit the autophagic flow, respectively, suggesting that autophagy exerts bona fide tumor-suppressive functions. In this review, we will discuss the mechanisms by which autophagy may prevent oncogenesis.
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20
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Abstract
The BH3 mimetic ABT737 induces autophagy by competitively disrupting the inhibitory interaction between the BH3 domain of Beclin 1 and the anti-apoptotic proteins Bcl-2 and Bcl-X(L), thereby stimulating the Beclin 1-dependent allosteric activation of the pro-autophagic lipid kinase VPS34. Here, we examined whether ABT737 stimulates other pro-autophagic signal-transduction pathways. ABT737 caused the activating phosphorylation of AMP-dependent kinase (AMPK) and of the AMPK substrate acetyl CoA carboxylase, the activating phosphorylation of several subunits of the inhibitor of NF-κB (IκB) kinase (IKK) and the hyperphosphorylation of the IKK substrate IκB, inhibition of the activity of mammalian target of rapamycin (mTOR) and consequent dephosphorylation of the mTOR substrate S6 kinase. In addition, ABT737 treatment dephosphorylates (and hence likewise inhibits) p53, glycogen synthase kinase-3 and Akt. All these effects were shared by ABT737 and another structurally unrelated BH3 mimetic, HA14-1. Functional experiments revealed that pharmacological or genetic inhibition of IKK, Sirtuin and the p53-depleting ubiquitin ligase MDM2 prevented ABT737-induced autophagy. These results point to unexpected and pleiotropic pro-autophagic effects of BH3 mimetics involving the modulation of multiple signalling pathways.
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21
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Strappazzon F, Vietri-Rudan M, Campello S, Nazio F, Florenzano F, Fimia GM, Piacentini M, Levine B, Cecconi F. Mitochondrial BCL-2 inhibits AMBRA1-induced autophagy. EMBO J 2011; 30:1195-208. [PMID: 21358617 DOI: 10.1038/emboj.2011.49] [Citation(s) in RCA: 186] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 02/04/2011] [Indexed: 11/09/2022] Open
Abstract
BECLIN 1 is a central player in macroautophagy. AMBRA1, a BECLIN 1-interacting protein, positively regulates the BECLIN 1-dependent programme of autophagy. In this study, we show that AMBRA1 binds preferentially the mitochondrial pool of the antiapoptotic factor BCL-2, and that this interaction is disrupted following autophagy induction. Further, AMBRA1 can compete with both mitochondrial and endoplasmic reticulum-resident BCL-2 (mito-BCL-2 and ER-BCL-2, respectively) to bind BECLIN 1. Moreover, after autophagy induction, AMBRA1 is recruited to BECLIN 1. Altogether, these results indicate that, in normal conditions, a pool of AMBRA1 binds preferentially mito-BCL-2; after autophagy induction, AMBRA1 is released from BCL-2, consistent with its ability to promote BECLIN 1 activity. In addition, we found that the binding between AMBRA1 and mito-BCL-2 is reduced during apoptosis. Thus, a dynamic interaction exists between AMBRA1 and BCL-2 at the mitochondria that could regulate both BECLIN 1-dependent autophagy and apoptosis.
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Affiliation(s)
- Flavie Strappazzon
- Laboratory of Molecular Neuroembryology, IRCCS Fondazione Santa Lucia, Rome, Italy
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22
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Lekli I, Ray D, Mukherjee S, Gurusamy N, Ahsan MK, Juhasz B, Bak I, Tosaki A, Gherghiceanu M, Popescu LM, Das DK. Co-ordinated autophagy with resveratrol and γ-tocotrienol confers synergetic cardioprotection. J Cell Mol Med 2011; 14:2506-18. [PMID: 19799646 PMCID: PMC3823167 DOI: 10.1111/j.1582-4934.2009.00921.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This study compared two dietary phytochemicals, grape-derived resveratrol and palm oil-derived γ-tocotrienol, either alone or in combination, on the contribution of autophagy in cardioprotection during ischaemia and reperfusion. Sprague-Dawley rats weighing between 250 and 300 g were randomly assigned to one of the following groups: vehicle, ischaemia/reperfusion (I/R), resveratrol + I/R, γ-tocotrienol + I/R, resveratrol +γ-tocotrienol + I/R. For resveratrol treatments, the rats were gavaged with resveratrol (2.5 mg/kg) for 15 days while for γ-tocotrienol experiments the rats were gavaged with γ-tocotrienol (0.3 mg/kg) for 30 days. For the combined resveratrol +γ-tocotrienol experiments, the rats were gavaged with γ-tocotrienol for 15 days, and then gavaging continued with resveratrol along with γ-tocotrienol for a further period of 15 days. After 30 days, isolated perfused hearts were subjected to 30 min. of global ischaemia followed by 2 hrs of reperfusion. Our results showed for the first time that at least in part, the cardioprotection (evidenced from the ventricular performance, myocardial infarct size and cardiomyocyte apoptosis) with resveratrol and γ-toctrienol was achieved by their abilities to induce autophagy. Most importantly, resveratrol and γ-tocotrienol acted synergistically providing greater degree of cardioprotection simultaneously generating greater amount of survival signal through the activation of Akt-Bcl-2 survival pathway. Autophagy was accompanied by the activation of Beclin and LC3-II as well as mTOR signalling, which were inhibited by either 3-methyl adenine (3-MA) or Wortmannin. The autophagy was confirmed from the results of transmission electron microscopy and light microscopy as well as with confocal microscopy. It is tempting to speculate that during ischaemia and reperfusion autophagy along with enhanced survival signals helps to recover the cells from injury.
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Affiliation(s)
- Istvan Lekli
- Cardiovascular Research Center, University of Connecticut School of Medicine, Farmington, CT 06030-1110, USA
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23
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Galluzzi L, Vanden Berghe T, Vanlangenakker N, Buettner S, Eisenberg T, Vandenabeele P, Madeo F, Kroemer G. Programmed necrosis from molecules to health and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 289:1-35. [PMID: 21749897 DOI: 10.1016/b978-0-12-386039-2.00001-8] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
During the past decade, cell death researchers have witnessed a gradual but deep conceptual revolution: it has been unequivocally shown that necrosis, which for long had been considered as a purely accidental cell death mode, can also be induced by finely regulated signal transduction pathways. In particular, when caspases are inhibited by pharmacological or genetic means, the ligation of death receptors such as the tumor necrosis factor receptor 1 (TNFR1) can lead to the assembly of a supramolecular complex containing the receptor-interacting protein kinases 1 and 3 (RIP1 and RIP3) that delivers a pronecrotic signal. Such complex has recently been dubbed necrosome and mediates the execution of a specific instance of regulated necrosis, necroptosis. Soon, it turned out that programmed necrosis occurs in nonmammalian model organisms and that it is implicated in human diseases including ischemia and viral infection. In this review, we first describe the historical evolution of the concept of programmed necrosis and the molecular mechanisms that underlie necroptosis initiation and execution. We then provide evidence suggesting that necroptosis represents an ancient and evolutionarily conserved cell death modality that may be targeted for drug development.
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Zhou F, Yang Y, Xing D. Bcl-2 and Bcl-xL play important roles in the crosstalk between autophagy and apoptosis. FEBS J 2010; 278:403-13. [PMID: 21182587 DOI: 10.1111/j.1742-4658.2010.07965.x] [Citation(s) in RCA: 315] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Autophagy and apoptosis play important roles in the development, cellular homeostasis and, especially, oncogenesis of mammals. They may be triggered by common upstream signals, resulting in combined autophagy and apoptosis. In other instances, they may be mutually exclusive. Recent studies have suggested possible molecular mechanisms for crosstalk between autophagy and apoptosis. Bcl-2 and Bcl-xL, the well-characterized apoptosis guards, appear to be important factors in autophagy, inhibiting Beclin 1-mediated autophagy by binding to Beclin 1. In addition, Beclin 1, Bcl-2 and Bcl-xL can cooperate with Atg5 or Ca(2+) to regulate both autophagy and apoptosis. Thus, Bcl-2 and Bcl-xL represent a molecular link between autophagy and apoptosis. Here, we discuss the possible roles of Bcl-2 and Bcl-xL in apoptosis and autophagy, and the crosstalk between them.
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Affiliation(s)
- Feifan Zhou
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
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25
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Niu TK, Cheng Y, Ren X, Yang JM. Interaction of Beclin 1 with survivin regulates sensitivity of human glioma cells to TRAIL-induced apoptosis. FEBS Lett 2010; 584:3519-24. [PMID: 20638385 DOI: 10.1016/j.febslet.2010.07.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 07/08/2010] [Accepted: 07/10/2010] [Indexed: 12/18/2022]
Abstract
We reported a novel interaction between Beclin 1, a key regulator of autophagy, and survivin, a member of the inhibitor of apoptosis protein family. We found that knock-down of Beclin 1 down-regulated survivin protein, and the turnover rate of survivin was increased when Beclin 1 expression was silenced. Knock-down of Beclin 1 sensitized glioma cells to TRAIL-induced apoptosis, and introduction of survivin antagonized the sensitizing effect, suggesting that down-regulation of survivin mediates the enhanced sensitivity to TRAIL-induced apoptosis. These results demonstrate a novel interaction between Beclin 1 and survivin, and may provide a potential mechanism underlying the cross-talk between autophagy and apoptosis.
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Affiliation(s)
- Ting-Kuang Niu
- Department of Pharmacology and The Penn State Cancer Institute, The Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, 500 University Drive, Hershey, PA 17033, USA
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Nikolic I, Kastratovic T, Zelen I, Zivanovic A, Arsenijevic S, Mitrovic M. Cytosolic pro-apoptotic SPIKE induces mitochondrial apoptosis in cancer. Biochem Biophys Res Commun 2010; 395:225-31. [DOI: 10.1016/j.bbrc.2010.03.168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 03/28/2010] [Indexed: 10/19/2022]
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27
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Abstract
Beclin 1 has a key role in the initiation of autophagy, a process of self-cannibalism in which cytoplasmic constituents are sequestered and targeted for lysosomal degradation. In a recent issue of Cell Death & Disease, Wirawan et al. report the significant finding that caspases can cleave Beclin 1, thereby destroying its pro-autophagic activity. Moreover, the C-terminal fragment of Beclin 1 that results from this cleavage acquires a new function and can amplify mitochondrion-mediated apoptosis. Of note, the BH3 domain of Beclin 1 remains within the N-terminal fragment, which has no detectable pro-apoptotic activity. These findings provide important insights into the molecular cross talk between autophagy and apoptosis.
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