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Wan JJ, Yi J, Wang FY, Li X, Zhang C, Song L, Dai AG. Role of mitophagy in pulmonary hypertension: Targeting the mechanism and pharmacological intervention. Mitochondrion 2024; 78:101928. [PMID: 38992857 DOI: 10.1016/j.mito.2024.101928] [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: 11/20/2023] [Revised: 05/29/2024] [Accepted: 07/07/2024] [Indexed: 07/13/2024]
Abstract
Mitophagy, a crucial pathway in eukaryotic cells, selectively eliminates dysfunctional mitochondria, thereby maintaining cellular homeostasis via mitochondrial quality control. Pulmonary hypertension (PH) refers to a pathological condition where pulmonary arterial pressure is abnormally elevated due to various reasons, and the underlying pathogenesis remains elusive. This article examines the molecular mechanisms underlying mitophagy, emphasizing its role in PH and the progress in elucidating related molecular signaling pathways. Additionally, it highlights current drug regulatory pathways, aiming to provide novel insights into the prevention and treatment of pulmonary hypertension.
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Affiliation(s)
- Jia-Jing Wan
- School of Integrated Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China
| | - Jian Yi
- The First Affiliated Hospital of Hunan University of Chinese Medicine, Changsha 410021, Hunan, China
| | - Fei-Ying Wang
- Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China
| | - Xia Li
- Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China
| | - Chao Zhang
- Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China
| | - Lan Song
- Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China
| | - Ai-Guo Dai
- Department of Respiratory Diseases, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China; Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, Changsha 410208, Hunan, China; Department of Respiratory Medicine, The First Affiliated Hospital of Hunan University of Chinese Medicine, Changsha 410021, Hunan, China.
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2
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Zhang X, Li Z, Zhang X, Yuan Z, Zhang L, Miao P. ATF family members as therapeutic targets in cancer: From mechanisms to pharmacological interventions. Pharmacol Res 2024; 208:107355. [PMID: 39179052 DOI: 10.1016/j.phrs.2024.107355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 08/09/2024] [Accepted: 08/15/2024] [Indexed: 08/26/2024]
Abstract
The activating transcription factor (ATF)/ cAMP-response element binding protein (CREB) family represents a large group of basic zone leucine zip (bZIP) transcription factors (TFs) with a variety of physiological functions, such as endoplasmic reticulum (ER) stress, amino acid stress, heat stress, oxidative stress, integrated stress response (ISR) and thus inducing cell survival or apoptosis. Interestingly, ATF family has been increasingly implicated in autophagy and ferroptosis in recent years. Thus, the ATF family is important for homeostasis and its dysregulation may promote disease progression including cancer. Current therapeutic approaches to modulate the ATF family include direct modulators, upstream modulators, post-translational modifications (PTMs) modulators. This review summarizes the structural domain and the PTMs feature of the ATF/CREB family and comprehensively explores the molecular regulatory mechanisms. On this basis, their pathways affecting proliferation, metastasis, and drug resistance in various types of cancer cells are sorted out and discussed. We then systematically summarize the status of the therapeutic applications of existing ATF family modulators and finally look forward to the future prospect of clinical applications in the treatment of tumors by modulating the ATF family.
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Affiliation(s)
- Xueyao Zhang
- Department of Anus and Intestine Surgery, Department of Cardiology, and Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang 110001, China
| | - Zhijia Li
- Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs, School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
| | - Xiaochun Zhang
- Department of Anus and Intestine Surgery, Department of Cardiology, and Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang 110001, China
| | - Ziyue Yuan
- Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs, School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
| | - Lan Zhang
- Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs, School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
| | - Peng Miao
- Department of Anus and Intestine Surgery, Department of Cardiology, and Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
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3
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Vringer E, Heilig R, Riley JS, Black A, Cloix C, Skalka G, Montes-Gómez AE, Aguado A, Lilla S, Walczak H, Gyrd-Hansen M, Murphy DJ, Huang DT, Zanivan S, Tait SW. Mitochondrial outer membrane integrity regulates a ubiquitin-dependent and NF-κB-mediated inflammatory response. EMBO J 2024; 43:904-930. [PMID: 38337057 PMCID: PMC10943237 DOI: 10.1038/s44318-024-00044-1] [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: 02/20/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/12/2024] Open
Abstract
Mitochondrial outer membrane permeabilisation (MOMP) is often essential for apoptosis, by enabling cytochrome c release that leads to caspase activation and rapid cell death. Recently, MOMP has been shown to be inherently pro-inflammatory with emerging cellular roles, including its ability to elicit anti-tumour immunity. Nonetheless, how MOMP triggers inflammation and how the cell regulates this remains poorly defined. We find that upon MOMP, many proteins localised either to inner or outer mitochondrial membranes are ubiquitylated in a promiscuous manner. This extensive ubiquitylation serves to recruit the essential adaptor molecule NEMO, leading to the activation of pro-inflammatory NF-κB signalling. We show that disruption of mitochondrial outer membrane integrity through different means leads to the engagement of a similar pro-inflammatory signalling platform. Therefore, mitochondrial integrity directly controls inflammation, such that permeabilised mitochondria initiate NF-κB signalling.
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Affiliation(s)
- Esmee Vringer
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Rosalie Heilig
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Joel S Riley
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
- Institute of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Annabel Black
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Catherine Cloix
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - George Skalka
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Alfredo E Montes-Gómez
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Aurore Aguado
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Sergio Lilla
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Henning Walczak
- Centre for Cell Death, Cancer, and Inflammation (CCCI), UCL Cancer Institute, University College London, London, UK
- CECAD Cluster of Excellence, University of Cologne, Cologne, Germany
- Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Mads Gyrd-Hansen
- Department of Immunology and Microbiology, LEO Foundation Skin Immunology Research Center, University of Copenhagen, Copenhagen, Denmark
| | - Daniel J Murphy
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Danny T Huang
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Sara Zanivan
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK
| | - Stephen Wg Tait
- Cancer Research UK Scotland Institute, Switchback Road, Glasgow, G61 1BD, UK.
- School of Cancer Sciences, University of Glasgow, Switchback Road, Glasgow, G61 1BD, UK.
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4
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Newman LE, Weiser Novak S, Rojas GR, Tadepalle N, Schiavon CR, Grotjahn DA, Towers CG, Tremblay MÈ, Donnelly MP, Ghosh S, Medina M, Rocha S, Rodriguez-Enriquez R, Chevez JA, Lemersal I, Manor U, Shadel GS. Mitochondrial DNA replication stress triggers a pro-inflammatory endosomal pathway of nucleoid disposal. Nat Cell Biol 2024; 26:194-206. [PMID: 38332353 PMCID: PMC11026068 DOI: 10.1038/s41556-023-01343-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/20/2023] [Indexed: 02/10/2024]
Abstract
Mitochondrial DNA (mtDNA) encodes essential subunits of the oxidative phosphorylation system, but is also a major damage-associated molecular pattern (DAMP) that engages innate immune sensors when released into the cytoplasm, outside of cells or into circulation. As a DAMP, mtDNA not only contributes to anti-viral resistance, but also causes pathogenic inflammation in many disease contexts. Cells experiencing mtDNA stress caused by depletion of the mtDNA-packaging protein, transcription factor A, mitochondrial (TFAM) or during herpes simplex virus-1 infection exhibit elongated mitochondria, enlargement of nucleoids (mtDNA-protein complexes) and activation of cGAS-STING innate immune signalling via mtDNA released into the cytoplasm. However, the relationship among aberrant mitochondria and nucleoid dynamics, mtDNA release and cGAS-STING activation remains unclear. Here we show that, under a variety of mtDNA replication stress conditions and during herpes simplex virus-1 infection, enlarged nucleoids that remain bound to TFAM exit mitochondria. Enlarged nucleoids arise from mtDNA experiencing replication stress, which causes nucleoid clustering via a block in mitochondrial fission at a stage when endoplasmic reticulum actin polymerization would normally commence, defining a fission checkpoint that ensures mtDNA has completed replication and is competent for segregation into daughter mitochondria. Chronic engagement of this checkpoint results in enlarged nucleoids trafficking into early and then late endosomes for disposal. Endosomal rupture during transit through this endosomal pathway ultimately causes mtDNA-mediated cGAS-STING activation. Thus, we propose that replication-incompetent nucleoids are selectively eliminated by an adaptive mitochondria-endosomal quality control pathway that is prone to innate immune system activation, which might represent a therapeutic target to prevent mtDNA-mediated inflammation during viral infection and other pathogenic states.
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Affiliation(s)
- Laura E Newman
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Gladys R Rojas
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | | | | | | | | | - Matthew P Donnelly
- Salk Institute for Biological Studies, La Jolla, CA, USA
- Medical Scientist Training Program, University of California, San Diego, La Jolla, CA, USA
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
| | - Sagnika Ghosh
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Sienna Rocha
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Joshua A Chevez
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Ian Lemersal
- La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Uri Manor
- Salk Institute for Biological Studies, La Jolla, CA, USA.
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA.
- Department of Cell & Developmental Biology, University of California, San Diego, La Jolla, CA, USA.
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5
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Atici AE, Crother TR, Noval Rivas M. Mitochondrial quality control in health and cardiovascular diseases. Front Cell Dev Biol 2023; 11:1290046. [PMID: 38020895 PMCID: PMC10657886 DOI: 10.3389/fcell.2023.1290046] [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: 09/06/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Cardiovascular diseases (CVDs) are one of the primary causes of mortality worldwide. An optimal mitochondrial function is central to supplying tissues with high energy demand, such as the cardiovascular system. In addition to producing ATP as a power source, mitochondria are also heavily involved in adaptation to environmental stress and fine-tuning tissue functions. Mitochondrial quality control (MQC) through fission, fusion, mitophagy, and biogenesis ensures the clearance of dysfunctional mitochondria and preserves mitochondrial homeostasis in cardiovascular tissues. Furthermore, mitochondria generate reactive oxygen species (ROS), which trigger the production of pro-inflammatory cytokines and regulate cell survival. Mitochondrial dysfunction has been implicated in multiple CVDs, including ischemia-reperfusion (I/R), atherosclerosis, heart failure, cardiac hypertrophy, hypertension, diabetic and genetic cardiomyopathies, and Kawasaki Disease (KD). Thus, MQC is pivotal in promoting cardiovascular health. Here, we outline the mechanisms of MQC and discuss the current literature on mitochondrial adaptation in CVDs.
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Affiliation(s)
- Asli E. Atici
- Department of Pediatrics, Division of Infectious Diseases and Immunology, Guerin Children’s at Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Infectious and Immunologic Diseases Research Center (IIDRC), Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Timothy R. Crother
- Department of Pediatrics, Division of Infectious Diseases and Immunology, Guerin Children’s at Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Infectious and Immunologic Diseases Research Center (IIDRC), Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Magali Noval Rivas
- Department of Pediatrics, Division of Infectious Diseases and Immunology, Guerin Children’s at Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Infectious and Immunologic Diseases Research Center (IIDRC), Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
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6
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Zhang M, Chen Y, Qiu Y, Sun J, He J, Liu Z, Shi J, Wei W, Wu G, Liang J. PCSK9 Promotes Hypoxia-Induced EC Pyroptosis by Regulating Smac Mitochondrion-Cytoplasm Translocation in Critical Limb Ischemia. JACC Basic Transl Sci 2023; 8:1060-1077. [PMID: 37791316 PMCID: PMC10544082 DOI: 10.1016/j.jacbts.2023.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 05/30/2023] [Accepted: 05/31/2023] [Indexed: 10/05/2023]
Abstract
Hypoxia-induced endothelial cell death and impaired angiogenesis are the main pathophysiological features of critical limb ischemia. Mechanistically, proprotein convertase subtilisin/kexin type 9 (PCSK9) promoted Smac translocation from mitochondria to the cytoplasm. Inhibition of Smac release into the cytoplasm attenuated PCSK9-mediated hypoxia-induced pyroptosis. Functionally, PCSK9 overexpression impaired angiogenesis in vitro and reduced blood perfusion in mice with lower limb ischemia, but the effect was reversed by PCSK9 inhibition. This study demonstrates that PCSK9 aggravates pyroptosis by regulating Smac mitochondrion-cytoplasm translocation in the vascular endothelium, providing novel insights into PCSK9 as a potential therapeutic target in critical limb ischemia.
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Affiliation(s)
- Meixin Zhang
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Yixi Chen
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Yumin Qiu
- Department of Hypertension and Vascular Disease, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jiapan Sun
- Department of Geriatrics, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Jiang He
- Department of Hypertension and Vascular Disease, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhefu Liu
- Department of Hypertension and Vascular Disease, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jian Shi
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Wenbin Wei
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Guifu Wu
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Jianwen Liang
- Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
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7
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Yan C, Li Y, Liu H, Chen D, Wu J. Antitumor mechanism of cannabidiol hidden behind cancer hallmarks. Biochim Biophys Acta Rev Cancer 2023; 1878:188905. [PMID: 37164234 DOI: 10.1016/j.bbcan.2023.188905] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/12/2023]
Abstract
Cannabinoids have been utilized for recreational and therapeutic purposes for over 4,000 years. As the primary ingredient in exogenous cannabinoids, Cannabidiol (CBD) has drawn a lot of interest from researchers due to its negligible psychotropic side effects and potential tumor-suppressing properties. However, the obscure mechanisms that underlie them remain a mystery. Complex biological mechanisms are involved in the progression of cancer, and malignancies have a variety of acquired biological capabilities, including sustained proliferation, death evasion, neovascularization, tissue invasion and metastasis, immune escape, metabolic reprogramming, induction of tumor-associated inflammation, cancerous stemness and genomic instability. Nowadays, the role of CBD hidden in these hallmarks is gradually revealed. Nevertheless, flaws or inconsistencies in the recent studies addressing the anti-cancer effects of CBD still exist. The purpose of this review is to evaluate the potential mechanisms underlying the role of CBD in a range of tumor-acquired biological capabilities. We propose potential drugs that may have a synergistic effect with CBD and provide optional directions for future research.
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Affiliation(s)
- Chaobiao Yan
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment For Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Hangzhou 310003, Zhejiang Province, China.
| | - Yu Li
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment For Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Hangzhou 310003, Zhejiang Province, China.
| | - Hanqing Liu
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment For Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Hangzhou 310003, Zhejiang Province, China.
| | - Diyu Chen
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment For Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Hangzhou 310003, Zhejiang Province, China.
| | - Jian Wu
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment For Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Hangzhou 310003, Zhejiang Province, China.
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8
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Nah J. The Role of Alternative Mitophagy in Heart Disease. Int J Mol Sci 2023; 24:ijms24076362. [PMID: 37047336 PMCID: PMC10094432 DOI: 10.3390/ijms24076362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 03/30/2023] Open
Abstract
Autophagy is essential for maintaining cellular homeostasis through bulk degradation of subcellular constituents, including misfolded proteins and dysfunctional organelles. It is generally governed by the proteins Atg5 and Atg7, which are critical regulators of the conventional autophagy pathway. However, recent studies have identified an alternative Atg5/Atg7-independent pathway, i.e., Ulk1- and Rab9-mediated alternative autophagy. More intensive studies have identified its essential role in stress-induced mitochondrial autophagy, also known as mitophagy. Alternative mitophagy plays pathophysiological roles in heart diseases such as myocardial ischemia and pressure overload. Here, this review discusses the established and emerging mechanisms of alternative autophagy/mitophagy that can be applied in therapeutic interventions for heart disorders.
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Affiliation(s)
- Jihoon Nah
- Department of Biochemistry, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju-si 28644, Chungcheongbuk-do, Republic of Korea
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9
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Vringer E, Tait SWG. Mitochondria and cell death-associated inflammation. Cell Death Differ 2023; 30:304-312. [PMID: 36447047 PMCID: PMC9950460 DOI: 10.1038/s41418-022-01094-w] [Citation(s) in RCA: 82] [Impact Index Per Article: 82.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 10/17/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
Mitochondria have recently emerged as key drivers of inflammation associated with cell death. Many of the pro-inflammatory pathways activated during cell death occur upon mitochondrial outer membrane permeabilization (MOMP), the pivotal commitment point to cell death during mitochondrial apoptosis. Permeabilised mitochondria trigger inflammation, in part, through the release of mitochondrial-derived damage-associated molecular patterns (DAMPs). Caspases, while dispensable for cell death during mitochondrial apoptosis, inhibit activation of pro-inflammatory pathways after MOMP. Some of these mitochondrial-activated inflammatory pathways can be traced back to the bacterial ancestry of mitochondria. For instance, mtDNA and bacterial DNA are highly similar thereby activating similar cell autonomous immune signalling pathways. The bacterial origin of mitochondria suggests that inflammatory pathways found in cytosol-invading bacteria may be relevant to mitochondrial-driven inflammation after MOMP. In this review, we discuss how mitochondria can initiate inflammation during cell death highlighting parallels with bacterial activation of inflammation. Moreover, we discuss the roles of mitochondrial inflammation during cell death and how these processes may potentially be harnessed therapeutically, for instance to improve cancer treatment.
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Affiliation(s)
- Esmee Vringer
- Cancer Research UK Beatson Institute, Glasgow, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
| | - Stephen W G Tait
- Cancer Research UK Beatson Institute, Glasgow, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
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10
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Zhao T, He Q, Xie S, Zhan H, Jiang C, Lin S, Liu F, Wang C, Chen G, Zeng H. A novel Mcl-1 inhibitor synergizes with venetoclax to induce apoptosis in cancer cells. Mol Med 2023; 29:10. [PMID: 36658493 PMCID: PMC9854187 DOI: 10.1186/s10020-022-00565-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/03/2022] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Evading apoptosis by overexpression of anti-apoptotic Bcl-2 family proteins is a hallmark of cancer cells and the Bcl-2 selective inhibitor venetoclax is widely used in the treatment of hematologic malignancies. Mcl-1, another anti-apoptotic Bcl-2 family member, is recognized as the primary cause of resistance to venetoclax treatment. However, there is currently no Mcl-1 inhibitor approved for clinical use. METHODS Paired parental and Mcl-1 knockout H1299 cells were used to screen and identify a small molecule named MI-238. Immunoprecipitation (IP) and flow cytometry assay were performed to analyze the activation of pro-apoptotic protein Bak. Annexin V staining and western blot analysis of cleaved caspase 3 were employed to measure the cell apoptosis. Mouse xenograft AML model using luciferase-expressing Molm13 cells was employed to evaluate in vivo therapeutic efficacy. Bone marrow samples from newly diagnosed AML patients were collected to evaluate the therapeutic potency. RESULTS Here, we show that MI-238, a novel and specific Mcl-1 inhibitor, can disrupt the association of Mcl-1 with BH3-only pro-apoptotic proteins, selectively leading to apoptosis in Mcl-1 proficient cells. Moreover, MI-238 treatment also potently induces apoptosis in acute myeloid leukemia (AML) cells. Notably, the combined treatment of MI-238 with venetoclax exhibited strong synergistic anti-cancer effects in AML cells in vitro, MOLM-13 xenografts mouse model and AML patient samples. CONCLUSIONS This study identified a novel and selective Mcl-1 inhibitor MI-238 and demonstrated that the development of MI-238 provides a novel strategy to improve the outcome of venetoclax therapy in AML.
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Affiliation(s)
- Tianming Zhao
- grid.412601.00000 0004 1760 3828Department of Hematology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630 China
| | - Qiang He
- grid.258164.c0000 0004 1790 3548Department of Medical Biochemistry and Molecular Biology, School of Medicine, Jinan University, Guangzhou, 510632 China
| | - Shurong Xie
- grid.412601.00000 0004 1760 3828Department of Hematology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630 China
| | - Huien Zhan
- grid.412601.00000 0004 1760 3828Department of Hematology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630 China
| | - Cheng Jiang
- grid.254147.10000 0000 9776 7793Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, 210009 China
| | - Shengbin Lin
- grid.258164.c0000 0004 1790 3548Department of Medical Biochemistry and Molecular Biology, School of Medicine, Jinan University, Guangzhou, 510632 China
| | - Fangshu Liu
- grid.412601.00000 0004 1760 3828Department of Hematology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630 China
| | - Cong Wang
- grid.254147.10000 0000 9776 7793School of Biopharmacy, China Pharmaceutical University, Nanjing, 211198 China
| | - Guo Chen
- grid.258164.c0000 0004 1790 3548Department of Medical Biochemistry and Molecular Biology, School of Medicine, Jinan University, Guangzhou, 510632 China ,grid.254147.10000 0000 9776 7793School of Biopharmacy, China Pharmaceutical University, Nanjing, 211198 China
| | - Hui Zeng
- grid.412601.00000 0004 1760 3828Department of Hematology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630 China
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11
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Zhang Y, Chen G, Yan Z, Wang L, Wang D. Hydrogen gas promotes apoptosis of lung adenocarcinoma A549 cells through X-linked inhibitor of apoptosis and baculoviral inhibitor of apoptosis protein repeat-containing 3. J Cancer Res Ther 2022; 18:1380-1386. [PMID: 36204886 DOI: 10.4103/jcrt.jcrt_1137_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Objective Lung cancer is currently the cancer with the highest incidence and death toll worldwide. Hydrogen gas has been found to affect a variety of diseases; however, the effect of hydrogen gas on patients with lung cancer has not been reported. Therefore, we determined the effect of hydrogen gas on apoptosis of lung adenocarcinoma in vivo and in vitro. Materials and Methods A549 cells in the logarithmic phase were treated with 20%, 40%, or 60% hydrogen gas. Cell apoptosis was evaluated by flow cytometry. The A549 cell suspension was inoculated into 15 nude mice. The mice were randomly divided into control, hydrogenation (inhalation of 60% hydrogen gas), and cisplatin groups (intraperitoneal injection of cisplatin [4 mg/kg]). After 3 weeks, the tumor tissue was removed and measured. We identified differentially expressed genes by transcriptional profiling. The levels of X-linked inhibitor of apoptosis (XIAP), baculoviral inhibitor of apoptosis protein repeat-containing 3 (BIRC3), and BCL2-associated X and apoptosis regulator (BAX) protein expression were detected by Western blotting and immunohistochemistry. Results Compared with the control group, the apoptosis rates in the 20%, 40%, and 60% hydrogen gas groups were significantly increased (P < 0.01). The levels of XIAP and BIRC3 protein expression were clearly decreased in the hydrogen gas group compared to the control group. Moreover, cisplatin and hydrogen gas reduced the tumor volume in nude mice (P < 0.01). Transcriptome sequencing showed that XIAP, BIRC2, BIRC3, BAX, PIK3CD, and ATM were related to apoptosis. Hydrogen gas further decreased the levels of XIAP and BIRC3 expression than in nude mice (P < 0.01). Conclusion Hydrogen gas promoted apoptosis of A549 cells by reducing the expression of XIAP and BIRC3 protein.
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Affiliation(s)
- Yu Zhang
- Department of General Medical, Hebei Medical University, Shijiazhuang, China
| | - Gang Chen
- Department of Respiration, Hebei Medical University, Shijiazhuang, China
| | - Zhenfeng Yan
- Department of Respiration, The People's Hospital of Baoding Mancheng, Baoding, China
| | - Lifei Wang
- Department of Respiration, Hebei Medical University, Shijiazhuang, China
| | - Dongchang Wang
- Department of General Medical, Hebei Medical University, Shijiazhuang, China
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12
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Xu W, Fang F, Wang Y, Qin L, Han Y, Huang Y, Li B, Liu Y, Wang Z. Co-overexpression of TRAIL and Smac sensitizes MDA-MB-231 cells to radiation through apoptosis depending on mitochondrial pathway. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2022; 61:37-48. [PMID: 35006369 DOI: 10.1007/s00411-021-00961-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Pro-apoptosis in cancer cells has been proposed as a beneficial therapeutic strategy for potentiating the anticancer effects of radiotherapy. TNF-related apoptosis inducing ligand (TRAIL) and Second mitochondria derived activator of caspase (Smac) can induce cell apoptosis. Herein, we designed a conditionally replicating adenoviral co-overexpression vector of TRAIL and Smac regulated by the Egr1 promoter, in which hTERT, E1A-E1B and E1B55K genes were inserted to achieve enhanced tumor targeting characteristics. After breast cancer MDA-MB-231 cells were infected and irradiated, cellular proliferation and colony formation were measured, apoptotic rate was detected by FCM after AnnexinV-FITC/PI staining. To explore the molecular mechanisms of apoptosis, mRNA and protein levels of TRAIL, Smac, Cytochrome c (Cyt c), death receptor 5 (DR5), caspase-8, -9 and -3 were measured by quantitative real-time PCR, ELISA and Western blot, and caspase-3 activity was detected using caspase-3 activity kits. The results showed that TRAIL and/or Smac overexpression enhanced proliferation inhibition and radio-sensitivity through apoptosis. In addition, the combination of IR and overexpression of TRAIL and/or Smac can activate more apoptosis in tumor cells, and the transcriptional levels and protein expressions of Cyt c, DR5, caspase-8, -9 and -3 had similar regularity with apoptotic changes, indicating the molecular mechanisms of TRAIL and Smac involves the mitochondrial pathway. Our findings may have implications for novel radiotherapy plans for breast tumor treatment.
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Affiliation(s)
- Weiqiang Xu
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Fang Fang
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Yuexuan Wang
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Lijing Qin
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Yu Han
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Yuwei Huang
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Bin Li
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China
| | - Yang Liu
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China.
| | - Zhicheng Wang
- NHC Key Laboratory of Radiobiology (Jilin University), School of Public Health, Jilin University, Changchun, 130021, People's Republic of China.
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13
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Subcellular localization of X-linked inhibitor of apoptosis protein (XIAP) in cancer: does that matter? BBA ADVANCES 2022; 2:100050. [PMID: 37082602 PMCID: PMC10074912 DOI: 10.1016/j.bbadva.2022.100050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/25/2022] [Accepted: 03/15/2022] [Indexed: 11/20/2022] Open
Abstract
X-linked inhibitor of apoptosis protein (XIAP) finely tunes the balance between survival and death to control homeostasis. XIAP is found aberrantly expressed in cancer, which has been shown to promote resistance to therapy-induced apoptosis and confer poor outcome. Despite its predominant cytoplasmic localization in human tissues, growing evidence implicates the expression of XIAP in other subcellular compartments in sustaining cancer hallmarks. Herein, we review our current knowledge on the prognostic role of XIAP localization and discuss molecular mechanisms underlying differential biological functions played in each compartment. The comprehension of XIAP subcellular shuttling and functional dynamics might provide the rationale for future anticancer therapeutics.
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14
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Mitophagy in Traumatic Brain Injury: A New Target for Therapeutic Intervention. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:4906434. [PMID: 35126814 PMCID: PMC8813270 DOI: 10.1155/2022/4906434] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 12/31/2021] [Accepted: 01/10/2022] [Indexed: 12/14/2022]
Abstract
Traumatic brain injury (TBI) contributes to death, and disability worldwide more than any other traumatic insult and damage to cellular components including mitochondria leads to the impairment of cellular functions and brain function. In neurons, mitophagy, autophagy-mediated degradation of damaged mitochondria, is a key process in cellular quality control including mitochondrial homeostasis and energy supply and plays a fundamental role in neuronal survival and health. Conversely, defective mitophagy leads to the accumulation of damaged mitochondria and cellular dysfunction, contributing to inflammation, oxidative stress, and neuronal cell death. Therefore, an extensive characterization of mitophagy-related protective mechanisms, taking into account the complex mechanisms by which each molecular player is connected to the others, may provide a rationale for the development of new therapeutic strategies in TBI patients. Here, we discuss the contribution of defective mitophagy in TBI, and the underlying molecular mechanisms of mitophagy in inflammation, oxidative stress, and neuronal cell death highlight novel therapeutics based on newly discovered mitophagy-inducing strategies.
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15
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Li Y, Zheng W, Lu Y, Zheng Y, Pan L, Wu X, Yuan Y, Shen Z, Ma S, Zhang X, Wu J, Chen Z, Zhang X. BNIP3L/NIX-mediated mitophagy: molecular mechanisms and implications for human disease. Cell Death Dis 2021; 13:14. [PMID: 34930907 PMCID: PMC8688453 DOI: 10.1038/s41419-021-04469-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 11/26/2021] [Accepted: 12/10/2021] [Indexed: 02/07/2023]
Abstract
Mitophagy is a highly conserved cellular process that maintains the mitochondrial quantity by eliminating dysfunctional or superfluous mitochondria through autophagy machinery. The mitochondrial outer membrane protein BNIP3L/Nix serves as a mitophagy receptor by recognizing autophagosomes. BNIP3L is initially known to clear the mitochondria during the development of reticulocytes. Recent studies indicated it also engages in a variety of physiological and pathological processes. In this review, we provide an overview of how BNIP3L induces mitophagy and discuss the biological functions of BNIP3L and its regulation at the molecular level. We further discuss current evidence indicating the involvement of BNIP3L-mediated mitophagy in human disease, particularly in cancer and neurological disorders.
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Affiliation(s)
- Yue Li
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Wanqing Zheng
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Yangyang Lu
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Yanrong Zheng
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmacology Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Ling Pan
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Xiaoli Wu
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Yang Yuan
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Zhe Shen
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Shijia Ma
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Xingxian Zhang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China
| | - Jiaying Wu
- Department of Pharmacy, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhong Chen
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China.
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmacology Science, Zhejiang Chinese Medical University, Hangzhou, China.
| | - Xiangnan Zhang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Key Laboratory of Medical Neurobiology of The Ministry of Health of China, Zhejiang University, Hangzhou, China.
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16
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Gupta R, Ambasta RK, Pravir Kumar. Autophagy and apoptosis cascade: which is more prominent in neuronal death? Cell Mol Life Sci 2021; 78:8001-8047. [PMID: 34741624 PMCID: PMC11072037 DOI: 10.1007/s00018-021-04004-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 02/06/2023]
Abstract
Autophagy and apoptosis are two crucial self-destructive processes that maintain cellular homeostasis, which are characterized by their morphology and regulated through signal transduction mechanisms. These pathways determine the fate of cellular organelle and protein involved in human health and disease such as neurodegeneration, cancer, and cardiovascular disease. Cell death pathways share common molecular mechanisms, such as mitochondrial dysfunction, oxidative stress, calcium ion concentration, reactive oxygen species, and endoplasmic reticulum stress. Some key signaling molecules such as p53 and VEGF mediated angiogenic pathway exhibit cellular and molecular responses resulting in the triggering of apoptotic and autophagic pathways. Herein, based on previous studies, we describe the intricate relation between cell death pathways through their common genes and the role of various stress-causing agents. Further, extensive research on autophagy and apoptotic machinery excavates the implementation of selective biomarkers, for instance, mTOR, Bcl-2, BH3 family members, caspases, AMPK, PI3K/Akt/GSK3β, and p38/JNK/MAPK, in the pathogenesis and progression of neurodegenerative diseases. This molecular phenomenon will lead to the discovery of possible therapeutic biomolecules as a pharmacological intervention that are involved in the modulation of apoptosis and autophagy pathways. Moreover, we describe the potential role of micro-RNAs, long non-coding RNAs, and biomolecules as therapeutic agents that regulate cell death machinery to treat neurodegenerative diseases. Mounting evidence demonstrated that under stress conditions, such as calcium efflux, endoplasmic reticulum stress, the ubiquitin-proteasome system, and oxidative stress intermediate molecules, namely p53 and VEGF, activate and cause cell death. Further, activation of p53 and VEGF cause alteration in gene expression and dysregulated signaling pathways through the involvement of signaling molecules, namely mTOR, Bcl-2, BH3, AMPK, MAPK, JNK, and PI3K/Akt, and caspases. Alteration in gene expression and signaling cascades cause neurotoxicity and misfolded protein aggregates, which are characteristics features of neurodegenerative diseases. Excessive neurotoxicity and misfolded protein aggregates lead to neuronal cell death by activating death pathways like autophagy and apoptosis. However, autophagy has a dual role in the apoptosis pathways, i.e., activation and inhibition of the apoptosis signaling. Further, micro-RNAs and LncRNAs act as pharmacological regulators of autophagy and apoptosis cascade, whereas, natural compounds and chemical compounds act as pharmacological inhibitors that rescue neuronal cell death through inhibition of apoptosis and autophagic cell death.
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Affiliation(s)
- Rohan Gupta
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Mechanical Engineering Building, Delhi Technological University (Formerly Delhi College of Engineering), Room# FW4TF3, Shahbad Daulatpur, Bawana Road, Delhi, 110042, India
| | - Rashmi K Ambasta
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Mechanical Engineering Building, Delhi Technological University (Formerly Delhi College of Engineering), Room# FW4TF3, Shahbad Daulatpur, Bawana Road, Delhi, 110042, India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Mechanical Engineering Building, Delhi Technological University (Formerly Delhi College of Engineering), Room# FW4TF3, Shahbad Daulatpur, Bawana Road, Delhi, 110042, India.
- , Delhi, India.
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17
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Zhang C, Zhu Z, Gao J, Yang L, Dang E, Fang H, Shao S, Zhang S, Xiao C, Yuan X, Li W, Abe R, Qiao H, Wang G, Fu M. Plasma exosomal miR-375-3p regulates mitochondria-dependent keratinocyte apoptosis by targeting XIAP in severe drug-induced skin reactions. Sci Transl Med 2021; 12:12/574/eaaw6142. [PMID: 33328332 DOI: 10.1126/scitranslmed.aaw6142] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/07/2020] [Accepted: 11/25/2020] [Indexed: 12/11/2022]
Abstract
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug-induced cutaneous reactions characterized by keratinocyte apoptosis. Exosomes are nanometer-sized membranous vesicles in body fluids. They contain functional proteins, mRNAs, and miRNAs, which induce immune dysfunction and influence disease progression. However, their roles and mechanisms in SJS/TEN remain unknown. Our results demonstrate that exosomes isolated from the plasma of patients with SJS/TEN were 30 to 200 nm in diameter and expressed CD9, CD63, CD81, and TSG101 exosome marker proteins. miR-375-3p was markedly up-regulated in 35 patients with SJS/TEN and correlated with clinical severity. Plasma exosomes were internalized by human primary keratinocytes and promoted keratinocyte apoptosis in vitro. Furthermore, miR-375-3p overexpression promoted intrinsic (mitochondria-dependent) apoptosis of human primary keratinocytes via down-regulation of the X-linked inhibitor of apoptosis protein (XIAP), a key apoptosis regulator in primary human keratinocytes. In sum, our study indicates that the circulating exosomal miR-375-3p enters keratinocytes, down-regulates XIAP, and induces keratinocyte apoptosis in patients with SJS/TEN.
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Affiliation(s)
- Chen Zhang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - ZhenLai Zhu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - JiXin Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - LuTing Yang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - ErLe Dang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Hui Fang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Shuai Shao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - ShaoLong Zhang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - ChunYing Xiao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Xu Yuan
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Wei Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Riichiro Abe
- Division of Dermatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - HongJiang Qiao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
| | - Gang Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
| | - Meng Fu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
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18
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Mechanisms of mitochondrial cell death. Biochem Soc Trans 2021; 49:663-674. [PMID: 33704419 DOI: 10.1042/bst20200522] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 12/23/2022]
Abstract
Mitochondria are double-membrane bound organelles that not only provide energy for intracellular metabolism, but also play a key role in the regulation of cell death. Mitochondrial outer membrane permeabilization (MOMP), allowing the release of intermembrane space proteins like cytochrome c, is considered a point of no return in apoptosis. MOMP is controlled by the proteins of the B-cell lymphoma 2 (BCL-2) family, including pro-and anti-apoptotic members, whose balance determines the decision between cell death and survival. Other factors such as membrane lipid environment, membrane dynamics, and inter-organelle communications are also known to influence this process. MOMP and apoptosis have been acknowledged as immunologically silent. Remarkably, a growing body of evidence indicates that MOMP can engage in various pro-inflammatory signaling functions. In this mini-review, we discuss about our current knowledge on the mechanisms of mitochondrial apoptosis, as well as the involvement of mitochondria in other kinds of programmed cell death pathways.
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19
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Abstract
Mitochondrial outer membrane permeabilization (MOMP) is a crucial event enabling apoptotic cell death. In this issue of Developmental Cell, Wang et al. reveal an interaction contributing to full MOMP execution, which depends on endosomes accumulating on apoptotic mitochondria. This causes mitochondrial lipid alterations that may contribute to functional pore assembly.
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Affiliation(s)
- Mariella Vicinanza
- Cambridge Institute for Medical Research, Department of Medical Genetics, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, Cambridge BioMedical Campus, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - David C Rubinsztein
- Cambridge Institute for Medical Research, Department of Medical Genetics, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Research Institute, Cambridge BioMedical Campus, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK.
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20
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Hollville E, Joers V, Nakamura A, Swahari V, Tansey MG, Moy SS, Deshmukh M. Characterization of a Cul9-Parkin double knockout mouse model for Parkinson's disease. Sci Rep 2020; 10:16886. [PMID: 33037272 PMCID: PMC7547682 DOI: 10.1038/s41598-020-73854-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 09/23/2020] [Indexed: 11/26/2022] Open
Abstract
Mitochondrial quality control is essential for the long-term survival of postmitotic neurons. The E3 ubiquitin ligase Parkin promotes the degradation of damaged mitochondria via mitophagy and mutations in Parkin are a major cause of early-onset Parkinson’s disease (PD). Surprisingly however, mice deleted for Parkin alone are rather asymptomatic for PD-related pathology, suggesting that other complementary or redundant mitochondrial quality control pathways may exist in neurons. Mitochondrial damage is often accompanied by the release of toxic proteins such as cytochrome c. We have reported that once in the cytosol, cytochrome c is targeted for degradation by the E3 ligase CUL9 in neurons. Here we examined whether CUL9 and Parkin cooperate to promote optimal neuronal survival in vivo. We generated mice deficient for both Cul9 and Parkin and examined them for PD-related phenotypes. Specifically, we conducted assays to examine behavioural deficits (locomotor, sensory, memory and learning) and loss of dopaminergic neurons in both males and females. Our results show that the loss of Cul9 and Parkin together did not enhance the effect of Parkin deficiency alone. These results indicate that while both Parkin and CUL9 participate in mitochondrial quality control, neurons likely have multiple redundant mechanisms to ensure their long-term survival.
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Affiliation(s)
- Emilie Hollville
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA.
| | - Valerie Joers
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Ayumi Nakamura
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Vijay Swahari
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Malú G Tansey
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Sheryl S Moy
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA.,Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, USA
| | - Mohanish Deshmukh
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA. .,Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA.
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21
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Wang Y, Pan Z, Cheng XL, Zhang K, Zhang X, Qin Y, Fan J, Yan T, Han T, Shiu KK, Hau SCK, Mak NK, Kwong DWJ, Liu X, Li M, Deng G, Zheng Q, Lu J, Li D. A red-light-activated sulfonamide porphycene for highly efficient photodynamic therapy against hypoxic tumor. Eur J Med Chem 2020; 209:112867. [PMID: 33010634 DOI: 10.1016/j.ejmech.2020.112867] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/24/2022]
Abstract
Photodynamic therapy (PDT) is an emerging alternative cancer treatment modality that utilizes photo-sensitivity to cause cell death upon photo-irradiation. However, PDT efficiency has been hampered by tumor hypoxia, blue-shifted excitation wavelengths, and the high dark toxicity of photo-sensitizers. We designed and synthesized two novel porphycene-based photosensitizers (TBPoS-OH and TBPoS-2OH) with potent photo-cytotoxicity and a LD50 in the nM range under both normoxic and hypoxic conditions in a variety of cell types after photo-irradiation (λ = 640 ± 15 nm). Further studies showed fast-cellular uptake for TBPoS-OH that localized lysosomes and subsequently induced cell apoptosis via the lysosomal-mitochondrial pathway. Moreover, TBPoS-OH significantly reduced tumor growth in two xenografted mouse models bearing melanoma A375 and B16 cells. Finally, TBPoS-OH exhibited no obvious immunogenicity and toxicity to blood cells and major organs in mice. These data demonstrated that these two porphycene-based photosensitizers, especially TBPoS-OH, could be developed as a potential PDT modality.
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Affiliation(s)
- Yuzhi Wang
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China; Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Zhaohai Pan
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, PR China
| | - Xiao-Lan Cheng
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210046, Jiangsu, PR China
| | - Kai Zhang
- College of Preclinical Medicine, Southwest Medical University, Luzhou, 646000, PR China
| | - Xin Zhang
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Yao Qin
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Jiaojiao Fan
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Ting Yan
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Tao Han
- College of Chemistry and Life Science, Chengdu Normal University, Chengdu, 611130, PR China
| | - Kwok Keung Shiu
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Sam Chun-Kit Hau
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Nai-Ki Mak
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Daniel W J Kwong
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, 999077, PR China
| | - Xiaona Liu
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Minjing Li
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Guowei Deng
- College of Chemistry and Life Science, Chengdu Normal University, Chengdu, 611130, PR China
| | - Qiusheng Zheng
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China
| | - Jun Lu
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, PR China; Institute of Integrated Bioinfomedicine & Translational Science, Hong Kong Baptist University Shenzhen Research Institute and Continuing Education, Shenzhen, 518000, China.
| | - Defang Li
- Yantai Key Laboratory of Pharmacology of Traditional Chinese Medicine in Tumor Metabolism, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, Shandong, PR China.
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Prajapati P, Gohel D, Shinde A, Roy M, Singh K, Singh R. TRIM32 regulates mitochondrial mediated ROS levels and sensitizes the oxidative stress induced cell death. Cell Signal 2020; 76:109777. [PMID: 32918979 DOI: 10.1016/j.cellsig.2020.109777] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 12/21/2022]
Abstract
Emerging evidence suggests that ubiquitin mediated post translational modification is a critical regulatory process involved in diverse cellular pathways including cell death. During ubiquitination, E3 ligases recognize target proteins and determine the topology of ubiquitin chains. Recruitment of E3 ligases to targets proteins under stress conditions including oxidative stress and their implication in cell death have not been systemically explored. In the present study, we characterized the role of TRIM32 as an E3 ligase in regulation of oxidative stress induced cell death. TRIM32 is ubiquitously expressed in cell lines of different origin and form cytoplasmic speckle like structures that transiently interact with mitochondria under oxidative stress conditions. The ectopic expression of TRIM32 sensitizes cell death induced by oxidative stress whereas TRIM32 knockdown shows a protective effect. The turnover of TRIM32 is enhanced during oxidative stress and its expression induces ROS generation, loss of mitochondrial transmembrane potential and decrease in complex-I activity. The pro-apoptotic effect was rescued by pan-caspase inhibitor or antioxidant treatment. E3 ligase activity of TRIM32 is essential for oxidative stress induced apoptotic cell death. Furthermore, TRIM32 decreases X-linked inhibitor of apoptosis (XIAP) level and overexpression of XIAP rescued cells from TRIM32 mediated oxidative stress and cell death. Overall, the results of this study provide the first evidence supporting the role of TRIM32 in regulating oxidative stress induced cell death, which has implications in numerous pathological conditions including cancer and neurodegeneration.
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Affiliation(s)
- Paresh Prajapati
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India; Spinal Cord and Brain Injury Research Center, Department of Pathology and Laboratory Medicine, University of Kentucky, 800 S. Limestone, Lexington, KY 40536, USA; Neuroscience, University of Kentucky, Lexington, KY 40536, USA
| | - Dhruv Gohel
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India
| | - Anjali Shinde
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India
| | - Milton Roy
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India
| | - Kritarth Singh
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India; Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Rajesh Singh
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India.
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Wang TS, Coppens I, Saorin A, Brady NR, Hamacher-Brady A. Endolysosomal Targeting of Mitochondria Is Integral to BAX-Mediated Mitochondrial Permeabilization during Apoptosis Signaling. Dev Cell 2020; 53:627-645.e7. [PMID: 32504557 DOI: 10.1016/j.devcel.2020.05.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 01/03/2020] [Accepted: 05/13/2020] [Indexed: 12/29/2022]
Abstract
Mitochondrial outer membrane permeabilization (MOMP) is a core event in apoptosis signaling. However, the underlying mechanism of BAX and BAK pore formation remains incompletely understood. We demonstrate that mitochondria are globally and dynamically targeted by endolysosomes (ELs) during MOMP. In response to pro-apoptotic BH3-only protein signaling and pharmacological MOMP induction, ELs increasingly form transient contacts with mitochondria. Subsequently, ELs rapidly accumulate within the entire mitochondrial compartment. This switch-like accumulation period temporally coincides with mitochondrial BAX clustering and cytochrome c release. Remarkably, interactions of ELs with mitochondria control BAX recruitment and pore formation. Knockdown of Rab5A, Rab5C, or USP15 interferes with EL targeting of mitochondria and functionally uncouples BAX clustering from cytochrome c release, while knockdown of the Rab5 exchange factor Rabex-5 impairs both BAX clustering and cytochrome c release. Together, these data reveal that EL-mitochondrial inter-organelle communication is an integral regulatory component of functional MOMP execution during cellular apoptosis signaling.
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Affiliation(s)
- Tim Sen Wang
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA; Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Isabelle Coppens
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Anna Saorin
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Nathan Ryan Brady
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
| | - Anne Hamacher-Brady
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA; Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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IAP-Mediated Protein Ubiquitination in Regulating Cell Signaling. Cells 2020; 9:cells9051118. [PMID: 32365919 PMCID: PMC7290580 DOI: 10.3390/cells9051118] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/12/2022] Open
Abstract
Over the last decade, the E3-ubiquitine ligases from IAP (Inhibitor of Apoptosis) family have emerged as potent regulators of immune response. In immune cells, they control signaling pathways driving differentiation and inflammation in response to stimulation of tumor necrosis factor receptor (TNFR) family, pattern-recognition receptors (PRRs), and some cytokine receptors. They are able to control the activity, the cellular fate, or the stability of actors of signaling pathways, acting at different levels from components of receptor-associated multiprotein complexes to signaling effectors and transcription factors, as well as cytoskeleton regulators. Much less is known about ubiquitination substrates involved in non-immune signaling pathways. This review aimed to present IAP ubiquitination substrates and the role of IAP-mediated ubiquitination in regulating signaling pathways.
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25
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Picca A, Calvani R, Coelho-Junior HJ, Landi F, Bernabei R, Marzetti E. Inter-Organelle Membrane Contact Sites and Mitochondrial Quality Control during Aging: A Geroscience View. Cells 2020; 9:cells9030598. [PMID: 32138154 PMCID: PMC7140483 DOI: 10.3390/cells9030598] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 02/28/2020] [Accepted: 02/29/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial dysfunction and failing mitochondrial quality control (MQC) are major determinants of aging. Far from being standalone organelles, mitochondria are intricately related with cellular other compartments, including lysosomes. The intimate relationship between mitochondria and lysosomes is reflected by the fact that lysosomal degradation of dysfunctional mitochondria is the final step of mitophagy. Inter-organelle membrane contact sites also allow bidirectional communication between mitochondria and lysosomes as part of nondegradative pathways. This interaction establishes a functional unit that regulates metabolic signaling, mitochondrial dynamics, and, hence, MQC. Contacts of mitochondria with the endoplasmic reticulum (ER) have also been described. ER-mitochondrial interactions are relevant to Ca2+ homeostasis, transfer of phospholipid precursors to mitochondria, and integration of apoptotic signaling. Many proteins involved in mitochondrial contact sites with other organelles also participate to degradative MQC pathways. Hence, a comprehensive assessment of mitochondrial dysfunction during aging requires a thorough evaluation of degradative and nondegradative inter-organelle pathways. Here, we present a geroscience overview on (1) degradative MQC pathways, (2) nondegradative processes involving inter-organelle tethering, (3) age-related changes in inter-organelle degradative and nondegradative pathways, and (4) relevance of MQC failure to inflammaging and age-related conditions, with a focus on Parkinson’s disease as a prototypical geroscience condition.
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Affiliation(s)
- Anna Picca
- Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS, 00168 Rome, Italy; (A.P.); (F.L.); (E.M.)
| | - Riccardo Calvani
- Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS, 00168 Rome, Italy; (A.P.); (F.L.); (E.M.)
- Correspondence: (R.C.); (R.B.); Tel.: +39-(06)-3015-5559 (R.C. & R.B.); Fax: +39-(06)-3051-911 (R.C. & R.B.)
| | - Hélio José Coelho-Junior
- Institute of Internal Medicine and Geriatrics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
| | - Francesco Landi
- Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS, 00168 Rome, Italy; (A.P.); (F.L.); (E.M.)
- Institute of Internal Medicine and Geriatrics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
| | - Roberto Bernabei
- Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS, 00168 Rome, Italy; (A.P.); (F.L.); (E.M.)
- Institute of Internal Medicine and Geriatrics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
- Correspondence: (R.C.); (R.B.); Tel.: +39-(06)-3015-5559 (R.C. & R.B.); Fax: +39-(06)-3051-911 (R.C. & R.B.)
| | - Emanuele Marzetti
- Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS, 00168 Rome, Italy; (A.P.); (F.L.); (E.M.)
- Institute of Internal Medicine and Geriatrics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
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Sironi L, Restelli LM, Tolnay M, Neutzner A, Frank S. Dysregulated Interorganellar Crosstalk of Mitochondria in the Pathogenesis of Parkinson's Disease. Cells 2020; 9:cells9010233. [PMID: 31963435 PMCID: PMC7016713 DOI: 10.3390/cells9010233] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/15/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
The pathogenesis of Parkinson’s disease (PD), the second most common neurodegenerative disorder, is complex and involves the impairment of crucial intracellular physiological processes. Importantly, in addition to abnormal α-synuclein aggregation, the dysfunction of various mitochondria-dependent processes has been prominently implicated in PD pathogenesis. Besides the long-known loss of the organelles’ bioenergetics function resulting in diminished ATP synthesis, more recent studies in the field have increasingly focused on compromised mitochondrial quality control as well as impaired biochemical processes specifically localized to ER–mitochondria interfaces (such as lipid biosynthesis and calcium homeostasis). In this review, we will discuss how dysregulated mitochondrial crosstalk with other organelles contributes to PD pathogenesis.
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Affiliation(s)
- Lara Sironi
- Division of Neuropathology, Institute of Medical Genetics and Pathology, University Hospital Basel, 4031 Basel, Switzerland; (L.M.R.); (M.T.)
- Correspondence: (L.S.); (S.F.); Tel.: +41-61-265-2776 (L.S. & S.F.)
| | - Lisa Michelle Restelli
- Division of Neuropathology, Institute of Medical Genetics and Pathology, University Hospital Basel, 4031 Basel, Switzerland; (L.M.R.); (M.T.)
| | - Markus Tolnay
- Division of Neuropathology, Institute of Medical Genetics and Pathology, University Hospital Basel, 4031 Basel, Switzerland; (L.M.R.); (M.T.)
| | - Albert Neutzner
- Department of Biomedicine, University Hospital Basel, University of Basel, 4031 Basel, Switzerland;
- Department of Ophthalmology University Hospital Basel, University of Basel, 4031 Basel, Switzerland
| | - Stephan Frank
- Division of Neuropathology, Institute of Medical Genetics and Pathology, University Hospital Basel, 4031 Basel, Switzerland; (L.M.R.); (M.T.)
- Correspondence: (L.S.); (S.F.); Tel.: +41-61-265-2776 (L.S. & S.F.)
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Pang L, Ding J, Ge Y, Fan J, Fan SK. Single-Cell-Derived Tumor-Sphere Formation and Drug-Resistance Assay Using an Integrated Microfluidics. Anal Chem 2019; 91:8318-8325. [DOI: 10.1021/acs.analchem.9b01084] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Long Pang
- School of Basic Medical Science, The Shaanxi Key Laboratory of Brain Disorders, Xi’an Medical University, Xi’an, 710021, China
- Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, 710049, China
| | - Jing Ding
- Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, 710049, China
| | - Yuxin Ge
- School of Basic Medical Science, The Shaanxi Key Laboratory of Brain Disorders, Xi’an Medical University, Xi’an, 710021, China
| | - Jianglin Fan
- School of Basic Medical Science, The Shaanxi Key Laboratory of Brain Disorders, Xi’an Medical University, Xi’an, 710021, China
| | - Shih-Kang Fan
- Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan
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28
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Pollock SR, Schinlever AR, Rohani A, Kashatus JA, Kashatus DF. RalA and RalB relocalization to depolarized mitochondria depends on clathrin-mediated endocytosis and facilitates TBK1 activation. PLoS One 2019; 14:e0214764. [PMID: 30995277 PMCID: PMC6469766 DOI: 10.1371/journal.pone.0214764] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/19/2019] [Indexed: 01/08/2023] Open
Abstract
Healthy mitochondria use an electrochemical gradient across the inner mitochondrial membrane (IMM) to generate energy in the form of ATP. A variety of endogenous and exogenous factors can lead to transient or sustained depolarization of the IMM, including mitochondrial fission events, expression of uncoupling proteins, electron transport chain (ETC) inhibitors, or chemical uncouplers. This depolarization in turn leads to a variety of physiological responses, ranging from selective mitochondrial clearance (mitophagy) to cell death. How cells recognize and ultimately respond to depolarized mitochondria remains incompletely understood. Here we show that the small GTPases RalA and RalB both relocalize to mitochondria following depolarization in a process dependent on clathrin-mediated endocytosis (CME). Furthermore, both genetic and pharmacologic inhibition of RalA and RalB leads to an increase in the activity of the atypical IκB kinase TBK1 both basally and in response to mitochondrial depolarization. This phenotype was also observed following inhibition of Ral relocalization. Collectively, these data suggest a model in which RalA and RalB inhibit TBK1 and that relocalization of Ral to depolarized mitochondria facilitates TBK1 activation through release of this inhibition.
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Affiliation(s)
- Sarah R. Pollock
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Austin R. Schinlever
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Ali Rohani
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Jennifer A. Kashatus
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - David F. Kashatus
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- * E-mail:
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29
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Wong YC, Kim S, Peng W, Krainc D. Regulation and Function of Mitochondria-Lysosome Membrane Contact Sites in Cellular Homeostasis. Trends Cell Biol 2019; 29:500-513. [PMID: 30898429 DOI: 10.1016/j.tcb.2019.02.004] [Citation(s) in RCA: 180] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/04/2019] [Accepted: 02/08/2019] [Indexed: 12/18/2022]
Abstract
Mitochondrial and lysosomal function are intricately related and critical for maintaining cellular homeostasis, as highlighted by multiple diseases linked to dysfunction of both organelles. Recent work using high-resolution microscopy demonstrates the dynamic formation of inter-organelle membrane contact sites between mitochondria and lysosomes, allowing for their direct interaction in a pathway distinct from mitophagy or lysosomal degradation of mitochondrial-derived vesicles. Mitochondria-lysosome contact site tethering is mechanistically regulated by mitochondrial proteins promoting Rab7 GTP hydrolysis, and allows for the bidirectional crosstalk between mitochondria and lysosomes and the regulation of their organelle network dynamics, including mitochondrial fission. In this review, we summarize recent advances in mitochondria-lysosome contact site regulation and function, and discuss their potential roles in cellular homeostasis and various human diseases.
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Affiliation(s)
- Yvette C Wong
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Soojin Kim
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Wesley Peng
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Dimitri Krainc
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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30
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Naik PP, Birbrair A, Bhutia SK. Mitophagy-driven metabolic switch reprograms stem cell fate. Cell Mol Life Sci 2019; 76:27-43. [PMID: 30267101 PMCID: PMC11105479 DOI: 10.1007/s00018-018-2922-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 09/12/2018] [Accepted: 09/19/2018] [Indexed: 12/19/2022]
Abstract
"Cellular reprogramming" facilitates the generation of desired cellular phenotype through the cell fate transition by affecting the mitochondrial dynamics and metabolic reshuffle in the embryonic and somatic stem cells. Interestingly, both the processes of differentiation and dedifferentiation witness a drastic and dynamic alteration in the morphology, number, distribution, and respiratory capacity of mitochondria, which are tightly regulated by the fission/fusion cycle, and mitochondrial clearance through autophagy following mitochondrial fission. Intriguingly, mitophagy is said to be essential in the differentiation of stem cells into various lineages such as erythrocytes, eye lenses, neurites, myotubes, and M1 macrophages. Mitophagy is also believed to play a central role in the dedifferentiation of a terminally differentiated cell into an induced pluripotent cell and in the acquisition of 'stemness' in cancer cells. Mitophagy-induced alteration in the mitochondrial dynamics facilitates metabolic shift, either into a glycolytic phenotype or into an OXPHOS phenotype, depending on the cellular demand. Mitophagy-induced rejuvenation of mitochondria regulates the transition of bioenergetics and metabolome, remodeling which facilitates an alteration in their cellular developmental capability. This review describes the detailed mechanism of the process of mitophagy and its association with cellular programming through alteration in the mitochondrial energetics. The metabolic shift post mitophagy is suggested to be a key factor in the cell fate transition during differentiation and dedifferentiation.
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Affiliation(s)
- Prajna Paramita Naik
- Department of Life Science, National Institute of Technology Rourkela, Rourkela, Odisha, 769008, India
- P.G. Department of Zoology, Vikram Deb (Auto) College, Jeypore, Odisha, 764001, India
| | - Alexander Birbrair
- Department of Pathology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sujit Kumar Bhutia
- Department of Life Science, National Institute of Technology Rourkela, Rourkela, Odisha, 769008, India.
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Han B, Jiang P, Li Z, Yu Y, Huang T, Ye X, Li X. Coptisine-induced apoptosis in human colon cancer cells (HCT-116) is mediated by PI3K/Akt and mitochondrial-associated apoptotic pathway. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2018; 48:152-160. [PMID: 30195873 DOI: 10.1016/j.phymed.2017.12.027] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/16/2017] [Accepted: 12/25/2017] [Indexed: 06/08/2023]
Abstract
BACKGROUND Colorectal cancer is the third leading cause of cancer-related deaths in the word. Coptisine (COP), an isoquinoline alkaloid derived from Coptis chinensis Franch, possesses a wide variety of pharmacological effects. However, its anti-proliferative effect on colon cancer is not fully elucidated. In the present study, we aimed to ascertain whether COP inhibits HCT-116 cell growth and to further explore the molecular mechanism in vitro and in vivo. METHODS Cell viability was determined by MTT assay. Cell migration was detected using wound healing assay. Apoptosis, mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) was analysis via flow cytometry. Hoechst 33342 was used for morphology observation. The expression levels of proteins related to mitochondrial-mediated apoptotic pathway were detected by western blotting. In addition, the antitumor ability of COP was further measured in athymic nude mice. RESULTS COP significantly decreased cell viability and migration in HCT-116 cells. Flow cytometry and Hoechst 33342 analysis confirmed that COP suppressed cell proliferation by inducing apoptosis. COP decreased Δψm dose-dependently and induced intracellular ROS production time-dependently. Western blotting showed that COP activated mitochondrial-associated apoptosis by down-regulating Bcl-2, Bcl-XL, pro-caspase 3, XIAP level and up-regulating Bax, Bad, cytochrome c, Apaf-1, AIF and cleaved caspase-3 expression. In addition, COP also attenuated PI3K/Akt signaling pathway. In vivo study showed that 150 mg/kg COP significantly delayed the tumor development in BALB/c nude mice. Immunohistochemical analysis also confirmed the activated apoptosis in tumor tissue. CONCLUSION The results demonstrated that COP induces apoptosis in HCT-116 cells through PI3K/Akt and mitochondrial-associated apoptotic pathway. Our findings suggest that COP has potential to be a therapeutic candidate for colon cancer patients.
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Affiliation(s)
- Bing Han
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China
| | - Pu Jiang
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China
| | - Zhaoxing Li
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China
| | - Yang Yu
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China
| | - Tao Huang
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China
| | - Xiaoli Ye
- School of Life Sciences, Southwest University, Chongqing, 400715, China; Chongqing Engineering Research Center for Pharmaceutical Process and Quality Control, Southwest University, Chongqing, 400716, China
| | - Xuegang Li
- Chongqing productivity promotion center for the modernization of Chinese traditional medicine, School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China; Chongqing Engineering Research Center for Pharmaceutical Process and Quality Control, Southwest University, Chongqing, 400716, China.
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Chen C, Liu TS, Zhao SC, Yang WZ, Chen ZP, Yan Y. XIAP impairs mitochondrial function during apoptosis by regulating the Bcl-2 family in renal cell carcinoma. Exp Ther Med 2018; 15:4587-4593. [PMID: 29731840 DOI: 10.3892/etm.2018.5974] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 03/13/2018] [Indexed: 01/15/2023] Open
Abstract
Efficient apoptosis requires Bcl-2 family-mediated mitochondrial outer membrane permeabilization (MOMP), which releases pro-apoptotic proteins to the cytosol, activating apoptosis and inhibiting X-linked inhibitor of apoptosis protein (XIAP). XIAP is a member of the inhibitors of apoptosis protein family whose expression is elevated in many cancer types and participates in the release of pro-apoptotic proteins. To explore the association between XIAP and the Bcl-2 family, and the influence of XIAP on mitochondria, RNA interference of XIAP was performed in Caki-1 cells and the dynamic change in the levels of related proteins was compared with the original Caki-1 cells upon induction of apoptosis. Upon knockdown of XIAP, the release of cytochrome c (Cyt-c), second mitochondria-derived activator of caspase (Smac) and apoptotic protease activating factor 1 (Apaf-1) from mitochondria proceeded normally, whereas in Caki-1 cells, the release of these pro-apoptotic proteins was significantly prolonged, and incomplete. Downregulation of XIAP through small interfering RNA resulted in an increase of apoptosis and a marked decrease in Bcl-2 and Bcl-xl levels at 3 h. Additionally, the regulation of the level of XIAP protein affected the specific ratios of Bcl-2/Bax and Bcl-xl/Bax, which play decisive roles in cell death. In the present study, it was revealed that XIAP can feed back to mitochondria, delaying Cyt-c and Apaf-1 release. Furthermore, XIAP can limit the release of its inhibitor Smac with the involvement of Bcl-2 family proteins.
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Affiliation(s)
- Chao Chen
- Department of Urology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, P.R. China
| | - Tian Shu Liu
- Department of Urology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, P.R. China
| | - Si Cong Zhao
- Department of Urology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, P.R. China
| | - Wen Zheng Yang
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, P.R. China
| | - Zong Ping Chen
- Department of Urology, The Affiliated Hospital of Zunyi Medical College, Zunyi 563000, P.R. China
| | - Yong Yan
- Department of Urology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, P.R. China
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Hsu F, Spannl S, Ferguson C, Hyman AA, Parton RG, Zerial M. Rab5 and Alsin regulate stress-activated cytoprotective signaling on mitochondria. eLife 2018; 7:32282. [PMID: 29469808 PMCID: PMC5847334 DOI: 10.7554/elife.32282] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 02/20/2018] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial stress response is essential for cell survival, and damaged mitochondria are a hallmark of neurodegenerative diseases. Thus, it is fundamental to understand how mitochondria relay information within the cell. Here, by investigating mitochondrial-endosomal contact sites we made the surprising observation that the small GTPase Rab5 translocates from early endosomes to mitochondria upon oxidative stress. This process is reversible and accompanied by an increase in Rab5-positive endosomes in contact with mitochondria. Interestingly, activation of Rab5 on mitochondria depends on the Rab5-GEF ALS2/Alsin, encoded by a gene mutated in amyotrophic lateral sclerosis (ALS). Alsin-deficient human-induced pluripotent stem cell-derived spinal motor neurons are defective in relocating Rab5 to mitochondria and display increased susceptibility to oxidative stress. These findings define a novel pathway whereby Alsin catalyzes the assembly of the Rab5 endocytic machinery on mitochondria. Defects in stress-sensing by endosomes could be crucial for mitochondrial quality control during the onset of ALS. The inside of a human cell is divided into compartments called organelles, which are surrounded by membranes. Each organelle plays a specific role in keeping the cell healthy and also has unique mix of molecular markers on its surface. These markers allow other molecules to identify the different organelles, meaning that specific organelles can communicate with each other and coordinate their activities. One way that organelles can do this is via so-called membrane contact sites, which are small areas where the compartments’ outer membranes come close together. Mitochondria are organelles that release energy inside human cells. These compartments also work to keep the levels of toxic chemicals called reactive oxygen species in the cell within a safe range. This is important because cells can die if these levels become too high – a state known as oxidative stress. Mitochondria also communicate with other organelles called endosomes, which receive materials from the cell surface, sort and direct them to different destinations throughout the cell. In many diseases affecting the nervous system, the mitochondria and endosomes in nerve cells do not work properly. These cells also have higher than normal levels of oxidative stress. Hsu et al. therefore wanted to find out if mitochondria and endosomes worked together to help cells to cope with this kind of stress. Hsu et al. triggered oxidative stress in human cancer cells by exposing them first to a dye that stained the mitochondria and then to intense light. In stressed cells, a subset of endosomes called early endosomes formed many more membrane contact sites with mitochondria than in non-stressed cells. At the same time, the protein Rab5, usually found on early endosomes, relocated to the surface of mitochondria. Human cells previously engineered to produce larger than normal amounts of Rab5 were also more likely to survive oxidative stress. These experiments suggested that early endosomes cooperate with mitochondria, via Rab5, to protect cells from oxidative stress. So, how is Rab5 relocated to mitochondria? Hsu et al. searched for activators of Rab5 and found that Alsin also migrated to mitochondria in stressed cells. The gene for Alsin is also mutated in amyotrophic lateral sclerosis (ALS), a degenerative nerve disorder that remains poorly understood. Next, Hsu et al. deleted the gene for Alsin from human stem cells growing in the laboratory and coaxed these cells into becoming nerve cells. Experiments with these cells showed that the absence of Alsin prevented Rab5 from moving to the mitochondria. Nerve cells lacking Alsin were also more susceptible to oxidative stress than normal cells. Together, these findings show that early endosomes work with mitochondria to sense and ward off oxidative stress. They also reveal an unexpected connection between this process and a gene mutated in ALS. Further experiments are now needed to explore if problems with endosomes or mitochondria, and specifically with molecules like Alsin and Rab5, are responsible for other neurodegenerative disorders, like Parkinson’s disease and Huntington’s disease.
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Affiliation(s)
- FoSheng Hsu
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Stephanie Spannl
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Charles Ferguson
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Robert G Parton
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia.,Centre for Microscopy and Microanalysis, University of Queensland, Brisbane, Australia
| | - Marino Zerial
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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Jin XJ, Cai PS, Zhu SP, Wang LJ, Zhu H. Negative correlation between X-linked inhibitors of apoptosis and second mitochondria-derived activator of caspase expression levels in cervical carcinoma and cervical intraepithelial neoplasia. Oncol Lett 2017; 14:5340-5346. [PMID: 29113168 PMCID: PMC5661384 DOI: 10.3892/ol.2017.6878] [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: 10/27/2015] [Accepted: 04/13/2017] [Indexed: 11/25/2022] Open
Abstract
X-linked inhibitors of apoptosis (XIAP) and second mitochondria-derived activator of caspase (Smac) have been widely reported to serve roles in the development of cervical carcinoma. The present study analyzed the associations between the expression levels of XIAP and Smac in normal cervical epithelium, cervical intraepithelial neoplasia (CIN) and cervical carcinoma. Immunohistochemistry staining of formalin-fixed, paraffin-embedded tissue sections was performed in order to analyze the expression levels of XIAP and Smac in 15 cases of normal cervical tissues, 69 cases of CIN and 76 cases of cervical carcinoma. All the tissue samples were confirmed by pathological diagnosis. The association of XIAP and Smac expression levels was analyzed using one-way analysis of variance, χ2 tests and Spearman's ρ for the nonparametric bi-variant correlation analysis. Overall survival was determined using the log-rank test and Kaplan-Meier survival curves. The expression level of XIAP was increased in CIN and cervical carcinoma tissues compared with normal cervical tissues, whereas Smac demonstrated a converse expression pattern to XIAP in these tissues. The positive staining level of XIAP protein was increased in grade 3 CIN compared with that in grade 1–2 CIN, and was significantly higher in the less-differentiated tissue of cervical carcinoma compared with the well- or medium-differentiated tissues (P<0.05). The staining level was also significantly increased in cervical carcinoma with stage 2b-3 compared with tissues from stage 1–2a carcinoma (P<0.05). The expression levels of Smac were in opposition to these results. XIAP was associated with pelvic lymph node metastasis, whereas no association was identified with Smac expression. The expression level of XIAP was significantly and negatively associated with cell survival time in cervical carcinoma, whereas the expression level of Smac was significantly and positively associated with cell survival time in cervical carcinoma. Therefore, XIAP and Smac may participate in the development of cervical cancer. The expression levels of XIAP and Smac were significantly and inversely associated. This may be useful in early diagnosis, evaluation of surgery and chemotherapy and the prognosis of cervical carcinoma.
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Affiliation(s)
- Xue-Jing Jin
- Departments of Obstetrics and Gynecology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, Zhejiang 325000, P.R. China
| | - Ping-Sheng Cai
- Departments of Obstetrics and Gynecology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, Zhejiang 325000, P.R. China
| | - Shu-Pin Zhu
- Departments of Obstetrics and Gynecology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, Zhejiang 325000, P.R. China
| | - Li-Jie Wang
- Departments of Obstetrics and Gynecology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, Zhejiang 325000, P.R. China
| | - Hua Zhu
- Departments of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
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35
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He M, Zhou Z, Wu G, Chen Q, Wan Y. Emerging role of DUBs in tumor metastasis and apoptosis: Therapeutic implication. Pharmacol Ther 2017; 177:96-107. [PMID: 28279784 PMCID: PMC5565705 DOI: 10.1016/j.pharmthera.2017.03.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Malfunction of ubiquitin-proteasome system is tightly linked to tumor formation and tumor metastasis. Targeting the ubiquitin-pathway provides a new strategy for anti-cancer therapy. Despite the parts played by ubiquitin modifiers, removal of ubiquitin from the functional proteins by the deubiquitinating enzymes (DUBs) plays an important role in governing the multiple steps of the metastatic cascade, including local invasion, dissemination, and eventual colonization of the tumor to distant organs. Both deregulated ubiquitination and deubiquitination could lead to dysregulation of various critical events and pathways such as apoptosis and epithelial-mesenchymal transition (EMT). Recent TCGA study has further revealed the connection between mutations of DUBs and various types of tumors. In addition, emerging drug design targeting DUBs provides a new strategy for anti-cancer therapy. In this review, we will summarize the role of deubiquitination and highlight the recent discoveries of DUBs with regards to multiple metastatic events including anti-apoptosis pathway and EMT. We will further discuss the regulation of deubiquitination as a novel strategy for anti-cancer therapy.
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Affiliation(s)
- Mingjing He
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, PR China.
| | - Zhuan Zhou
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
| | - George Wu
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
| | - Qianming Chen
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, PR China.
| | - Yong Wan
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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Pang L, Liu W, Tian C, Xu J, Li T, Chen SW, Wang J. Construction of single-cell arrays and assay of cell drug resistance in an integrated microfluidic platform. LAB ON A CHIP 2016; 16:4612-4620. [PMID: 27785515 DOI: 10.1039/c6lc01000h] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The cellular heterogeneity of tumors has played important roles in various tumor-related research areas and applications such as the cellular biology, metastasis and clinical diagnosis of tumors. Although several microfluidics-based single-cell separation and analysis techniques have been used in research into the cellular heterogeneity of tumors, further investigation is still required for studying the effect of the biomechanical (e.g., size and deformability) heterogeneity of cells on their biological characteristics (e.g., drug resistance and tumor-initiating features). Here, we established an integrated microfluidic platform for the construction of single-cell arrays and analysis of drug resistance. Using this device, high-throughput single-cell arrays could be easily obtained according to the biomechanical (size and deformability) heterogeneity of cells. To demonstrate the capability of the microfluidic platform, a proof-of-concept experiment was implemented by determining the vincristine resistance of single glioblastoma cells with different biomechanical properties. The results indicated that the biomechanics of tumor cells had significant implications for cell drug resistance; that is, small and/or more deformable tumor cells had higher drug resistance than large and/or less deformable tumor cells. This device provides a new approach for the isolation of single cells according to the different biomechanical properties of cells. Also, it possesses practical potential for studies of tumors on a single-cell level.
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Affiliation(s)
- Long Pang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Wenming Liu
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Chang Tian
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Juan Xu
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Tianbao Li
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Shu-Wei Chen
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jinyi Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China. and College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
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37
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Hamacher-Brady A, Brady NR. Mitophagy programs: mechanisms and physiological implications of mitochondrial targeting by autophagy. Cell Mol Life Sci 2016; 73:775-95. [PMID: 26611876 PMCID: PMC4735260 DOI: 10.1007/s00018-015-2087-8] [Citation(s) in RCA: 291] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 10/30/2015] [Accepted: 11/02/2015] [Indexed: 02/07/2023]
Abstract
Mitochondria are an essential source of ATP for cellular function, but when damaged, mitochondria generate a plethora of stress signals, which lead to cellular dysfunction and eventually programmed cell death. Thus, a major component of maintaining cellular homeostasis is the recognition and removal of dysfunctional mitochondria through autophagy-mediated degradation, i.e., mitophagy. Mitophagy further constitutes a developmental program, and undergoes a high degree of crosstalk with apoptosis. Reduced mitochondrial quality control is linked to disease pathogenesis, suggesting the importance of process elucidation as a clinical target. Recent work has revealed multiple mitophagy programs that operate independently or undergo crosstalk, and require modulated autophagy receptor activities at outer membranes of mitochondria. Here, we review these mitophagy programs, focusing on pathway mechanisms which recognize and target mitochondria for sequestration by autophagosomes, as well as mechanisms controlling pathway activities. Furthermore, we provide an introduction to the currently available methods for detecting mitophagy.
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Affiliation(s)
- Anne Hamacher-Brady
- Lysosomal Systems Biology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Bioquant, University of Heidelberg, INF 267, BQ0045, 69120, Heidelberg, Germany.
| | - Nathan Ryan Brady
- Systems Biology of Cell Death Mechanisms, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Department of Surgery, Heidelberg University Hospital, Heidelberg, Germany.
- Bioquant, University of Heidelberg, INF 267, BQ0045, 69120, Heidelberg, Germany.
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38
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Liu W, Xu J, Li T, Zhao L, Ma C, Shen S, Wang J. Monitoring tumor response to anticancer drugs using stable three-dimensional culture in a recyclable microfluidic platform. Anal Chem 2015; 87:9752-60. [PMID: 26337449 DOI: 10.1021/acs.analchem.5b01915] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The development and application of miniaturized platforms with the capability for microscale and dynamic control of biomimetic and high-throughput three-dimensional (3D) culture plays a crucial role in biological research. In this study, pneumatic microstructure-based microfluidics was used to systematically demonstrate 3D tumor culture under various culture conditions. We also demonstrated the reusability of the fabrication-optimized pneumatic device for high-throughput cell manipulation and 3D tumor culture. This microfluidic system provides remarkably long-term (over 1 month) and cyclic stability. Furthermore, temporal and high-throughput monitoring of tumor response to evaluate the therapeutic efficacy of different chemotherapies, was achieved based on the robust culture. This advancement in microfluidics has potential applications in the fields of tissue engineering, tumor biology, and clinical medicine; it also provides new insight into the construction of high-performance and recyclable microplatforms for cancer research.
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Affiliation(s)
- Wenming Liu
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Juan Xu
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Tianbao Li
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Lei Zhao
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Chao Ma
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Shaofei Shen
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
| | - Jinyi Wang
- College of Science and ‡College of Veterinary Medicine, Northwest A&F University , Yangling, Shaanxi 712100, China
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39
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Choe SC, Hamacher-Brady A, Brady NR. Autophagy capacity and sub-mitochondrial heterogeneity shape Bnip3-induced mitophagy regulation of apoptosis. Cell Commun Signal 2015; 13:37. [PMID: 26253153 PMCID: PMC4528699 DOI: 10.1186/s12964-015-0115-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 07/28/2015] [Indexed: 12/15/2022] Open
Abstract
Background Mitochondria are key regulators of apoptosis. In response to stress, BH3-only proteins activate pro-apoptotic Bcl2 family proteins Bax and Bak, which induce mitochondrial outer membrane permeabilization (MOMP). While the large-scale mitochondrial release of pro-apoptotic proteins activates caspase-dependent cell death, a limited release results in sub-lethal caspase activation which promotes tumorigenesis. Mitochondrial autophagy (mitophagy) targets dysfunctional mitochondria for degradation by lysosomes, and undergoes extensive crosstalk with apoptosis signaling, but its influence on apoptosis remains undetermined. The BH3-only protein Bnip3 integrates apoptosis and mitophagy signaling at different signaling domains. Bnip3 inhibits pro-survival Bcl2 members via its BH3 domain and activates mitophagy through its LC3 Interacting Region (LIR), which is responsible for binding to autophagosomes. Previously, we have shown that Bnip3-activated mitophagy prior to apoptosis induction can reduce mitochondrial activation of caspases, suggesting that a reduction to mitochondrial levels may be pro-survival. An outstanding question is whether organelle dynamics and/or recently discovered subcellular variations of protein levels responsible for both MOMP sensitivity and crosstalk between apoptosis and mitophagy can influence the cellular apoptosis decision event. To that end, here we undertook a systems biology analysis of mitophagy-apoptosis crosstalk at the level of cellular mitochondrial populations. Results Based on experimental findings, we developed a multi-scale, hybrid model with an individually adaptive mitochondrial population, whose actions are determined by protein levels, embedded in an agent-based model (ABM) for simulating subcellular dynamics and local feedback via reactive oxygen species signaling. Our model, supported by experimental evidence, identified an emergent regulatory structure within canonical apoptosis signaling. We show that the extent of mitophagy is determined by levels and spatial localization of autophagy capacity, and subcellular mitochondrial protein heterogeneities. Our model identifies mechanisms and conditions that alter the mitophagy decision within mitochondrial subpopulations to an extent sufficient to shape cellular outcome to apoptotic stimuli. Conclusion Overall, our modeling approach provides means to suggest new experiments and implement findings at multiple scales in order to understand how network topologies and subcellular heterogeneities can influence signaling events at individual organelle level, and hence, determine the emergence of heterogeneity in cellular decisions due the actions of the collective intra-cellular population. Electronic supplementary material The online version of this article (doi:10.1186/s12964-015-0115-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sehyo Charley Choe
- Systems Biology of Cell Death Mechanisms, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Department of Surgery, Heidelberg University Hospital, Heidelberg, Germany.,Bioquant, University of Heidelberg, Heidelberg, Germany
| | - Anne Hamacher-Brady
- Bioquant, University of Heidelberg, Heidelberg, Germany.,Lysosomal Systems Biology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Nathan Ryan Brady
- Systems Biology of Cell Death Mechanisms, German Cancer Research Center (DKFZ), Heidelberg, Germany. .,Department of Surgery, Heidelberg University Hospital, Heidelberg, Germany. .,Bioquant, University of Heidelberg, Heidelberg, Germany.
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40
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Chaudhary AK, Yadav N, Bhat TA, O'Malley J, Kumar S, Chandra D. A potential role of X-linked inhibitor of apoptosis protein in mitochondrial membrane permeabilization and its implication in cancer therapy. Drug Discov Today 2015; 21:38-47. [PMID: 26232549 DOI: 10.1016/j.drudis.2015.07.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/09/2015] [Accepted: 07/21/2015] [Indexed: 12/17/2022]
Abstract
X-chromosome-linked inhibitor of apoptosis protein (XIAP) has an important regulatory role in programmed cell death by inhibiting the caspase cascade. Activation of XIAP-dependent signaling culminates into regulation of multiple cellular processes including apoptosis, innate immunity, epithelial-to-mesenchymal transition, cell migration, invasion, metastasis and differentiation. Although XIAP localizes to the cytosolic compartment, XIAP-mediated cellular signaling encompasses mitochondrial and post-mitochondrial levels. Recent findings demonstrate that XIAP also localizes to mitochondria and regulates mitochondria functions. XIAP acts upstream of mitochondrial cytochrome c release and modulates caspase-dependent apoptosis. The new function of XIAP has potential to enhance mitochondrial membrane permeabilization and other cellular functions controlling cytochrome c release. These findings could exploit the overexpression of XIAP in human tumors for therapeutic benefits.
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Affiliation(s)
- Ajay K Chaudhary
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Neelu Yadav
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Tariq A Bhat
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Jordan O'Malley
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Sandeep Kumar
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Dhyan Chandra
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
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Hamacher-Brady A, Brady NR. Bax/Bak-dependent, Drp1-independent Targeting of X-linked Inhibitor of Apoptosis Protein (XIAP) into Inner Mitochondrial Compartments Counteracts Smac/DIABLO-dependent Effector Caspase Activation. J Biol Chem 2015; 290:22005-18. [PMID: 26134559 DOI: 10.1074/jbc.m115.643064] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Indexed: 11/06/2022] Open
Abstract
Efficient apoptosis requires Bax/Bak-mediated mitochondrial outer membrane permeabilization (MOMP), which releases death-promoting proteins cytochrome c and Smac to the cytosol, which activate apoptosis and inhibit X-linked inhibitor of apoptosis protein (XIAP) suppression of executioner caspases, respectively. We recently identified that in response to Bcl-2 homology domain 3 (BH3)-only proteins and mitochondrial depolarization, XIAP can permeabilize and enter mitochondria. Consequently, XIAP E3 ligase activity recruits endolysosomes into mitochondria, resulting in Smac degradation. Here, we explored mitochondrial XIAP action within the intrinsic apoptosis signaling pathway. Mechanistically, we demonstrate that mitochondrial XIAP entry requires Bax or Bak and is antagonized by pro-survival Bcl-2 proteins. Moreover, intramitochondrial Smac degradation by XIAP occurs independently of Drp1-regulated cytochrome c release. Importantly, mitochondrial XIAP actions are activated cell-intrinsically by typical apoptosis inducers TNF and staurosporine, and XIAP overexpression reduces the lag time between the administration of an apoptotic stimuli and the onset of mitochondrial permeabilization. To elucidate the role of mitochondrial XIAP action during apoptosis, we integrated our findings within a mathematical model of intrinsic apoptosis signaling. Simulations suggest that moderate increases of XIAP, combined with mitochondrial XIAP preconditioning, would reduce MOMP signaling. To test this scenario, we pre-activated XIAP at mitochondria via mitochondrial depolarization or by artificially targeting XIAP to the intermembrane space. Both approaches resulted in suppression of TNF-mediated caspase activation. Taken together, we propose that XIAP enters mitochondria through a novel mode of mitochondrial permeabilization and through Smac degradation can compete with canonical MOMP to act as an anti-apoptotic tuning mechanism, reducing the mitochondrial contribution to the cellular apoptosis capacity.
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Affiliation(s)
- Anne Hamacher-Brady
- From the Lysosomal Systems Biology, German Cancer Research Center, Bioquant, University of Heidelberg, 69120 Heidelberg, Germany
| | - Nathan Ryan Brady
- Bioquant, University of Heidelberg, 69120 Heidelberg, Germany the Systems Biology of Cell Death Mechanisms, German Cancer Research Center, the Department of Surgery, Heidelberg University Hospital, and
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