601
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The Function of Autophagy in Neurodegenerative Diseases. Int J Mol Sci 2015; 16:26797-812. [PMID: 26569220 PMCID: PMC4661849 DOI: 10.3390/ijms161125990] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 10/30/2015] [Accepted: 11/02/2015] [Indexed: 12/11/2022] Open
Abstract
Macroautophagy, hereafter referred to as autophagy, is a bulk degradation process performed by lysosomes in which aggregated and altered proteins as well as dysfunctional organelles are decomposed. Autophagy is a basic cellular process that maintains homeostasis and is crucial for postmitotic neurons. Thus, impaired autophagic processes in neurons lead to improper homeostasis and neurodegeneration. Recent studies have suggested that impairments of the autophagic process are associated with several neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and static encephalopathy of childhood with neurodegeneration in adulthood. In this review, we focus on the recent findings regarding the autophagic process and the involvement of autophagy in neurodegenerative diseases.
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602
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Mukai S, Moriya S, Hiramoto M, Kazama H, Kokuba H, Che XF, Yokoyama T, Sakamoto S, Sugawara A, Sunazuka T, Ōmura S, Handa H, Itoi T, Miyazawa K. Macrolides sensitize EGFR-TKI-induced non-apoptotic cell death via blocking autophagy flux in pancreatic cancer cell lines. Int J Oncol 2015; 48:45-54. [PMID: 26718641 PMCID: PMC4734605 DOI: 10.3892/ijo.2015.3237] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/15/2015] [Indexed: 01/05/2023] Open
Abstract
Pancreatic cancer is one of the most difficult types of cancer to treat because of its high mortality rate due to chemotherapy resistance. We previously reported that combined treatment with gefitinib (GEF) and clarithromycin (CAM) results in enhanced cytotoxicity of GEF along with endoplasmic reticulum (ER) stress loading in non-small cell lung cancer cell lines. An epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) such as GEF induces autophagy in a pro-survival role, whereas CAM inhibits autophagy flux in various cell lines. Pronounced GEF-induced cytotoxicity therefore appears to depend on the efficacy of autophagy inhibition. In the present study, we compared the effect on autophagy inhibition among such macrolides as CAM, azithromycin (AZM), and EM900, a novel 12-membered non-antibiotic macrolide. We then assessed the enhanced GEF-induced cytotoxic effect on pancreatic cancer cell lines BxPC-3 and PANC-1. Autophagy flux analysis indicated that AZM is the most effective autophagy inhibitor of the three macrolides. CAM exhibits an inhibitory effect but less than AZM and EM900. Notably, the enhancing effect of GEF-induced cytotoxicity by combining macrolides correlated well with their efficient autophagy inhibition. However, this pronounced cytotoxicity was not due to upregulation of apoptosis induction, but was at least partially mediated through necroptosis. Our data suggest the possibility of using macrolides as ‘chemosensitizers’ for EGFR-TKI therapy in pancreatic cancer patients to enhance non-apoptotic tumor cell death induction.
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Affiliation(s)
- Shuntaro Mukai
- Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan
| | - Shota Moriya
- Department of Biochemistry, Tokyo Medical University, Tokyo, Japan
| | - Masaki Hiramoto
- Department of Biochemistry, Tokyo Medical University, Tokyo, Japan
| | - Hiromi Kazama
- Department of Biochemistry, Tokyo Medical University, Tokyo, Japan
| | - Hiroko Kokuba
- Laboratory of Electron Microscopy, Tokyo Medical University, Tokyo, Japan
| | - Xiao-Fang Che
- Department of Biochemistry, Tokyo Medical University, Tokyo, Japan
| | - Tomohisa Yokoyama
- Department of Clinical Oncology, Tokyo Medical University, Tokyo, Japan
| | - Satoshi Sakamoto
- Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan
| | - Akihiro Sugawara
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Toshiaki Sunazuka
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Satoshi Ōmura
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Hiroshi Handa
- Department of Nanoparticle Translational Research, Tokyo Medical University, Tokyo, Japan
| | - Takao Itoi
- Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan
| | - Keisuke Miyazawa
- Department of Biochemistry, Tokyo Medical University, Tokyo, Japan
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603
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Villanueva Paz M, Cotán D, Garrido-Maraver J, Cordero MD, Oropesa-Ávila M, de La Mata M, Delgado Pavón A, de Lavera I, Alcocer-Gómez E, Sánchez-Alcázar JA. Targeting autophagy and mitophagy for mitochondrial diseases treatment. Expert Opin Ther Targets 2015; 20:487-500. [PMID: 26523761 DOI: 10.1517/14728222.2016.1101068] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Mitochondrial diseases are a group of rare genetic diseases with complex and heterogeneous origins which manifest a great variety of phenotypes. Disruption of the oxidative phosphorylation system is the main cause of pathogenicity in mitochondrial diseases since it causes accumulation of reactive oxygen species (ROS) and ATP depletion. AREAS COVERED Current evidences support the main protective role of autophagy and mitophagy in mitochondrial diseases and other diseases associated with mitochondrial dysfunction. EXPERT OPINION The use of autophagy and/or mitophagy inducers may allow a novel strategy for improving mitochondrial function for both mitochondrial diseases and other diseases with altered mitochondrial metabolism. However, a deeper investigation of the molecular mechanisms behind mitophagy and mitochondrial biogenesis is needed in order to safely modulate these processes. In the coming years, we will also see an increase in awareness of mitochondrial dynamics modulation that will allow the therapeutic use of new drugs for improving mitochondrial function in a great variety of mitochondrial disorders.
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Affiliation(s)
- Marina Villanueva Paz
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - David Cotán
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Juan Garrido-Maraver
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Mario D Cordero
- b Facultad de Odontología , Universidad de Sevilla , Sevilla 41009 , Spain
| | - Manuel Oropesa-Ávila
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Mario de La Mata
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Ana Delgado Pavón
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Isabel de Lavera
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - Elizabet Alcocer-Gómez
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
| | - José A Sánchez-Alcázar
- a Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III , Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas , Carretera de Utrera Km 1, Sevilla 41013 , Spain
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604
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Lionaki E, Markaki M, Palikaras K, Tavernarakis N. Mitochondria, autophagy and age-associated neurodegenerative diseases: New insights into a complex interplay. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1412-23. [DOI: 10.1016/j.bbabio.2015.04.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 04/10/2015] [Accepted: 04/20/2015] [Indexed: 12/22/2022]
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605
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Torres A, Luke JD, Kullas AL, Kapilashrami K, Botbol Y, Koller A, Tonge PJ, Chen EI, Macian F, van der Velden AWM. Asparagine deprivation mediated by Salmonella asparaginase causes suppression of activation-induced T cell metabolic reprogramming. J Leukoc Biol 2015; 99:387-98. [PMID: 26497246 DOI: 10.1189/jlb.4a0615-252r] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 10/02/2015] [Indexed: 01/09/2023] Open
Abstract
Salmonellae are pathogenic bacteria that induce immunosuppression by mechanisms that remain largely unknown. Previously, we showed that a putative type II l-asparaginase produced by Salmonella Typhimurium inhibits T cell responses and mediates virulence in a murine model of infection. Here, we report that this putative L-asparaginase exhibits L-asparagine hydrolase activity required for Salmonella Typhimurium to inhibit T cells. We show that L-asparagine is a nutrient important for T cell activation and that L-asparagine deprivation, such as that mediated by the Salmonella Typhimurium L-asparaginase, causes suppression of activation-induced mammalian target of rapamycin signaling, autophagy, Myc expression, and L-lactate secretion. We also show that L-asparagine deprivation mediated by the Salmonella Typhimurium L-asparaginase causes suppression of cellular processes and pathways involved in protein synthesis, metabolism, and immune response. Our results advance knowledge of a mechanism used by Salmonella Typhimurium to inhibit T cell responses and mediate virulence, and provide new insights into the prerequisites of T cell activation. We propose a model in which l-asparagine deprivation inhibits T cell exit from quiescence by causing suppression of activation-induced metabolic reprogramming.
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Affiliation(s)
- AnnMarie Torres
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Joanna D Luke
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Amy L Kullas
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Kanishk Kapilashrami
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Yair Botbol
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Antonius Koller
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Peter J Tonge
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Emily I Chen
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Fernando Macian
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Adrianus W M van der Velden
- *Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Graduate Program in Genetics, Department of Chemistry and Institute for Chemical Biology and Drug Discovery, Proteomics Center, and Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, USA; and Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
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606
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Karyotypic Aberrations in Oncogenesis and Cancer Therapy. Trends Cancer 2015; 1:124-135. [DOI: 10.1016/j.trecan.2015.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 08/05/2015] [Accepted: 08/07/2015] [Indexed: 12/27/2022]
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607
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Xiong J. Atg7 in development and disease: panacea or Pandora's Box? Protein Cell 2015; 6:722-34. [PMID: 26404030 PMCID: PMC4598325 DOI: 10.1007/s13238-015-0195-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 07/13/2015] [Indexed: 01/15/2023] Open
Abstract
Macroautophagy is an evolutionarily conserved intracellular degradation system used by life ranging from yeasts to mammals. The core autophagic machinery is composed of ATG (autophagy-related) protein constituents. One particular member of the ATG protein family, Atg7, has been the focus of recent research. Atg7 acts as an E1-like activating enzyme facilitating both microtubule-associated protein light chain 3 (LC3)-phosphatidylethanolamine and ATG12 conjugation. Thus, Atg7 stands at the hub of these two ubiquitin-like systems involving LC3 and Atg12 in autophagic vesicle expansion. In this review, I focus on the pleiotropic function of Atg7 in development, maintenance of health, and alternations of such control in disease.
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Affiliation(s)
- Jianhua Xiong
- Center for Molecular Medicine, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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608
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Tiras HP, Gudkov SV, Emelyanenko VI, Aslanidi KB. Intrinsic chemiluminescence of neoblasts in the course of planarian regeneration. Biophysics (Nagoya-shi) 2015. [DOI: 10.1134/s000635091505022x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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609
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Lacritin and other autophagy associated proteins in ocular surface health. Exp Eye Res 2015; 144:4-13. [PMID: 26318608 DOI: 10.1016/j.exer.2015.08.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 07/20/2015] [Accepted: 08/18/2015] [Indexed: 12/19/2022]
Abstract
Advantage may be taken of macroautophagy ('autophagy') to promote ocular health. Autophagy continually captures aged or damaged cellular material for lysosomal degradation and recyling. When autophagic flux is chronically elevated, or alternatively deficient, health suffers. Chronic elevation of flux and stress are the consequence of inflammatory cytokines or of dry eye tears but not normal tears invitro. Exogenous tear protein lacritin transiently accelerates flux to restore homeostasis invitro and corneal health invivo, and yet the monomeric active form of lacritin appears to be selectively deficient in dry eye. Tissue transglutaminase-dependent cross-linking of monomer decreases monomer quantity and monomer affinity for coreceptor syndecan-1 thereby abrogating activity. Tissue transglutaminase is elevated in dry eye. Mutation of arylsulfatase A, arylsulfatase B, ceroid-lipofuscinosis neuronal 3, mucolipin, or Niemann-Pick disease type C1 respectively underlie several diseases of apparently insufficient autophagic flux that affect the eye, including: metachromatic leukodystrophy, mucopolysaccharidosis type VI, juvenile-onset Batten disease, mucolipidosis IV, and Niemann-Pick type C associated with myelin sheath destruction of corneal sensory and ciliary nerves and of the optic nerve; corneal clouding, ocular hypertension, glaucoma and optic nerve atrophy; accumulation of 'ceroid-lipofuscin' in surface conjunctival cells, and in ganglion and neuronal cells; decreased visual acuity and retinal dystrophy; and neurodegeneration. For some, enzyme or gene replacement, or substrate reduction, therapy is proving to be successful. Here we discuss examples of restoring ocular surface homeostasis through alteration of autophagy, with particular attention to lacritin.
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610
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Ha J, Guan KL, Kim J. AMPK and autophagy in glucose/glycogen metabolism. Mol Aspects Med 2015; 46:46-62. [PMID: 26297963 DOI: 10.1016/j.mam.2015.08.002] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 08/04/2015] [Indexed: 12/14/2022]
Abstract
Glucose/glycogen metabolism is a primary metabolic pathway acting on a variety of cellular needs, such as proliferation, growth, and survival against stresses. The multiple regulatory mechanisms underlying a specific metabolic fate have been documented and explained the molecular basis of various pathophysiological conditions, including metabolic disorders and cancers. AMP-activated protein kinase (AMPK) has been appreciated for many years as a central metabolic regulator to inhibit energy-consuming pathways as well as to activate the compensating energy-producing programs. In fact, glucose starvation is a potent physiological AMPK activating condition, in which AMPK triggers various subsequent metabolic events depending on cells or tissues. Of note, the recent studies show bidirectional interplay between AMPK and glycogen. A growing number of studies have proposed additional level of metabolic regulation by a lysosome-dependent catabolic program, autophagy. Autophagy is a critical degradative pathway not only for maintenance of cellular homeostasis to remove potentially dangerous constituents, such as protein aggregates and dysfunctional subcellular organelles, but also for adaptive responses to metabolic stress, such as nutrient starvation. Importantly, many lines of evidence indicate that autophagy is closely connected with nutrient signaling modules, including AMPK, to fine-tune the metabolic pathways in response to many different cellular cues. In this review, we introduce the studies demonstrating the role of AMPK and autophagy in glucose/glycogen metabolism. Also, we describe the recent advances on their contributions to the metabolic disorders.
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Affiliation(s)
- Joohun Ha
- Department of Biochemistry and Molecular Biology, Medical Research Center and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Kun-Liang Guan
- Department of Pharmacology, Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Joungmok Kim
- Department of Oral Biochemistry and Molecular Biology, Research Center for Tooth and Periodontal Tissue Regeneration, School of Dentistry, Kyung Hee University, Seoul, Republic of Korea.
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611
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Liu XY, He YJ, Yang QH, Huang W, Liu ZH, Ye GR, Tang SH, Shu JC. Induction of autophagy and apoptosis by miR-148a through the sonic hedgehog signaling pathway in hepatic stellate cells. Am J Cancer Res 2015; 5:2569-2589. [PMID: 26609469 PMCID: PMC4633891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 07/27/2015] [Indexed: 06/05/2023] Open
Abstract
Autophagy is an evolutionarily conserved biological process that is activated in response to stress. Increasing evidence indicate that dysregulated miRNAs significantly contribute to autophagy and are thus implicated in various pathological conditions, including hepatic fibrosis. MiR-148a, a member of the miR-148/152 family, has been found to be downregulated in hepatic fibrosis and human hepatocellular carcinoma. However, the role of miR-148a in the development of hepatic fibrosis remains largely unknown. In this study, we describe the epigenetic regulation of miR-148a and its impact on autophagy in hepatic stellate cells (HSCs), exploring new targets of miR-148a. We found that miR-148a expression was significantly increased under starvation-induced conditions in LX-2 and T-6 cells. In addition, dual-luciferase reporter assays showed that miR-148a suppressed target gene expression by directly interacting with the 3'-untranslated regions (3'-UTRs) of growth arrest-specific gene 1 (Gas1) transcripts. Intriguingly, Gas1, which encodes a Hedgehog surface binding receptor and facilitates the Hedgehog (Hh) signaling pathway, inhibited autophagosome synthesis. Furthermore, we demonstrated a novel function for miR-148a as a potent inducer of autophagy in HSCs. Overexpressing of miR-148a increased autophagic activity, which inhibited proliferation and promoted apoptosis in HSCs. In conclusion, these data support a novel role for miR-148a as a key regulator of autophagy through the Hh signaling pathway, making miR-148a a potential candidate for the development of novel therapeutic strategies.
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Affiliation(s)
- Xu-You Liu
- Department of Gastroenterology, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
| | - Ya-Jun He
- Center of Clinical Laboratory Medicine, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
| | - Qi-Hong Yang
- Department of Gastroenterology, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
| | - Wei Huang
- Department of Gastroenterology, The First Affiliated Hospital, Jinan UniversityGuangzhou 510630, China
| | - Zhi-He Liu
- Guangzhou Institute of Traumatic Surgery, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
| | - Guo-Rong Ye
- Department of Gastroenterology, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
| | - Shao-Hui Tang
- Department of Gastroenterology, The First Affiliated Hospital, Jinan UniversityGuangzhou 510630, China
| | - Jian-Chang Shu
- Department of Gastroenterology, The Fourth Affiliated Hospital of Jinan University, Guangzhou Red Cross HospitalGuangzhou 510220, China
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612
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Choi JY, Hong WG, Cho JH, Kim EM, Kim J, Jung CH, Hwang SG, Um HD, Park JK. Podophyllotoxin acetate triggers anticancer effects against non-small cell lung cancer cells by promoting cell death via cell cycle arrest, ER stress and autophagy. Int J Oncol 2015; 47:1257-65. [PMID: 26314270 PMCID: PMC4583522 DOI: 10.3892/ijo.2015.3123] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 07/24/2015] [Indexed: 01/07/2023] Open
Abstract
We previously reported that podophyllotoxin acetate (PA) radiosensitizes NCI-H460 cells. Here, we confirmed that PA treatment also induces cell death among two other non-small cell lung cancer (NSCLC) cell lines: NCI-H1299 and A549 cells (IC50 values = 7.6 and 16.1 nM, respectively). Our experiments further showed that PA treatment was able to induce cell death via various mechanisms. First, PA dose-dependently induced cell cycle arrest at G2/M phase, as shown by accumulation of the mitosis-related proteins, p21, survivin and Aurora B. This G2/M phase arrest was due to the PA-induced inhibition of microtubule polymerization. Together, the decreased microtubule polymerization and increased cell cycle arrest induced DNA damage (reflected by accumulation of γ-H2AX) and triggered the induction of intrinsic and extrinsic apoptotic pathways, as shown by the time-dependent activations of caspase-3, -8 and -9. Second, PA time-dependently activated the pro-apoptotic ER stress pathway, as evidenced by increased expression levels of BiP, CHOP, IRE1-α, phospho-PERK, and phospho-JNK. Third, PA activated autophagy, as reflected by time-dependent increases in the expression levels of beclin-1, Atg3, Atg5 and Atg7, and the cleavage of LC3. Collectively, these results suggest a model wherein PA decreases microtubule polymerization and increases cell cycle arrest, thereby inducing apoptotic cell death via the activation of DNA damage, ER stress and autophagy.
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Affiliation(s)
- Jae Yeon Choi
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Wan Gi Hong
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Jeong Hyun Cho
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Eun Mi Kim
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Jongdoo Kim
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Chan-Hun Jung
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Sang-Gu Hwang
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Hong-Duck Um
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Jong Kuk Park
- Department of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
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613
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Pharmacological inhibition of fatty-acid oxidation synergistically enhances the effect of l-asparaginase in childhood ALL cells. Leukemia 2015; 30:209-18. [DOI: 10.1038/leu.2015.213] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 07/03/2015] [Accepted: 07/10/2015] [Indexed: 01/08/2023]
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614
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Kenney DL, Benarroch EE. The autophagy-lysosomal pathway: General concepts and clinical implications. Neurology 2015. [PMID: 26203091 DOI: 10.1212/wnl.0000000000001860] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Daniel L Kenney
- From the Departments of Child and Adolescent Neurology (D.L.K.) and Neurology (E.E.B.), Mayo Clinic, Rochester, MN
| | - Eduardo E Benarroch
- From the Departments of Child and Adolescent Neurology (D.L.K.) and Neurology (E.E.B.), Mayo Clinic, Rochester, MN.
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615
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Chen L, Ye HL, Zhang G, Yao WM, Chen XZ, Liang G. Effect of (-)-epigallocatechin-3- O-gallate on autophagic signaling in HepG2 cells. Shijie Huaren Xiaohua Zazhi 2015; 23:3022-3028. [DOI: 10.11569/wcjd.v23.i19.3022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the changes of autophagy in hepatocellular carcinoma (HCC) HepG2 cells in response to (-)-epigallocatechin-3-O-gallate (EGCG), and to explore its impact on cell proliferation and death.
METHODS: HepG2 cells were routinely cultured and re-plated in Dulbecco's modified eagle's medium (DMEM) in the presence of EGCG of different concentrations. Transmission electron microscopic technique was used to record the formation of autophagosomes in HepG2 cells. Real-time RT-PCR and Western blot were used to detect the mRNA and protein expression of autophagy-related genes, respectively. MTT and trypan blue assays were carried out to determine the cellular proliferation and death. Autophagic intervention experiment was performed to evaluate whether changes in autophagy are involved in the anti-cancer efficacy of EGCG in HCC.
RESULTS: The proliferation of HepG2 cells was significantly inhibited by EGCG and was negatively related to the concentrations of this compound (r = -0.9341, P < 0.001). Doses of EGCG that could effectively inhibit the proliferation of HepG2 cells significantly decreased the mRNA and protein expression of Beclin1 and Atg5, with increments of P62 named autophagic substrate as well as substantially reduced numbers of autophagasomes found in these cells. Moreover, up-regulating autophagy with rapamycin was found to apparently impair the effect of EGCG in killing HepG2 cells (t = 9.95, P < 0.01), while 3-MA, an autophagy inhibitor, dramatically exaggerated the anti-cancer effects of EGCG (t = 22.82, P < 0.01).
CONCLUSION: EGCG substantially inhibits cell proliferation and promotes cell death in HCC cells via down-regulation of autophagy, which indicates a novel critical pharmacological mechanism of EGCG for hepatoma therapy.
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616
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Optineurin: The autophagy connection. Exp Eye Res 2015; 144:73-80. [PMID: 26142952 DOI: 10.1016/j.exer.2015.06.029] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 06/03/2015] [Accepted: 06/30/2015] [Indexed: 01/13/2023]
Abstract
Optineurin is a cytosolic protein encoded by the OPTN gene. Mutations of OPTN are associated with normal tension glaucoma and amyotrophic lateral sclerosis. Autophagy is an intracellular degradation system that delivers cytoplasmic components to the lysosomes. It plays a wide variety of physiological and pathophysiological roles. The optineurin protein is a selective autophagy receptor (or adaptor), containing an ubiquitin binding domain with the ability to bind polyubiquitinated cargoes and bring them to autophagosomes via its microtubule-associated protein 1 light chain 3-interacting domain. It is involved in xenophagy, mitophagy, aggrephagy, and tumor suppression. Optineurin can also mediate the removal of protein aggregates through an ubiquitin-independent mechanism. This protein in addition can induce autophagy upon overexpression or mutation. When overexpressed or mutated, the optineurin protein also serves as a substrate for autophagic degradation. In the present review, the multiple connections of optineurin to autophagy are highlighted.
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617
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Tintignac LA, Brenner HR, Rüegg MA. Mechanisms Regulating Neuromuscular Junction Development and Function and Causes of Muscle Wasting. Physiol Rev 2015; 95:809-52. [DOI: 10.1152/physrev.00033.2014] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The neuromuscular junction is the chemical synapse between motor neurons and skeletal muscle fibers. It is designed to reliably convert the action potential from the presynaptic motor neuron into the contraction of the postsynaptic muscle fiber. Diseases that affect the neuromuscular junction may cause failure of this conversion and result in loss of ambulation and respiration. The loss of motor input also causes muscle wasting as muscle mass is constantly adapted to contractile needs by the balancing of protein synthesis and protein degradation. Finally, neuromuscular activity and muscle mass have a major impact on metabolic properties of the organisms. This review discusses the mechanisms involved in the development and maintenance of the neuromuscular junction, the consequences of and the mechanisms involved in its dysfunction, and its role in maintaining muscle mass during aging. As life expectancy is increasing, loss of muscle mass during aging, called sarcopenia, has emerged as a field of high medical need. Interestingly, aging is also accompanied by structural changes at the neuromuscular junction, suggesting that the mechanisms involved in neuromuscular junction maintenance might be disturbed during aging. In addition, there is now evidence that behavioral paradigms and signaling pathways that are involved in longevity also affect neuromuscular junction stability and sarcopenia.
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Affiliation(s)
- Lionel A. Tintignac
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
| | - Hans-Rudolf Brenner
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
| | - Markus A. Rüegg
- Biozentrum, University of Basel, Basel, Switzerland; Department of Biomedicine, University of Basel, Basel, Switzerland; and INRA, UMR866 Dynamique Musculaire et Métabolisme, Montpellier, France
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618
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Autophagy sustains the survival of human pancreatic cancer PANC-1 cells under extreme nutrient deprivation conditions. Biochem Biophys Res Commun 2015; 463:205-10. [DOI: 10.1016/j.bbrc.2015.05.022] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 05/08/2015] [Indexed: 11/20/2022]
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619
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Broxmeyer HE, O'Leary HA, Huang X, Mantel C. The importance of hypoxia and extra physiologic oxygen shock/stress for collection and processing of stem and progenitor cells to understand true physiology/pathology of these cells ex vivo. Curr Opin Hematol 2015; 22:273-8. [PMID: 26049746 PMCID: PMC4721218 DOI: 10.1097/moh.0000000000000144] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF REVIEW Hematopoietic stem (HSCs) and progenitor (HPCs) cells reside in a hypoxic (lowered oxygen tension) environment, in vivo. We review literature on growth of HSCs and HPCs under hypoxic and normoxic (ambient air) conditions with a focus on our recent work demonstrating the detrimental effects of collecting and processing cells in ambient air through a phenomenon termed extra physiologic oxygen shock/stress (EPHOSS), and we describe means to counteract EPHOSS for enhanced collection of HSCs. RECENT FINDINGS Collection and processing of bone marrow and cord blood cells in ambient air cause rapid differentiation and loss of HSCs, with increases in HPCs. This apparently irreversible EPHOSS phenomenon results from increased mitochondrial reactive oxygen species, mediated by a p53-cyclophilin D-mitochondrial permeability transition pore axis, and involves hypoxia inducing factor-1α and micro-RNA 210. EPHOSS can be mitigated by collecting and processing cells in lowered (3%) oxygen, or in ambient air in the presence of, cyclosporine A which effects the mitochondrial permeability transition pore, resulting in increased HSC collections. SUMMARY Our recent findings may be advantageous for HSC collection for hematopoietic cell transplantation, and likely for enhanced collection of other stem cell types. EPHOSS should be considered when ex-vivo cell analysis is utilized for personalized medicine, as metabolism of cells and their response to targeted drug treatment ex vivo may not mimic what occurs in vivo.
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Affiliation(s)
- Hal E Broxmeyer
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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620
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Rimessi A, Patergnani S, Bonora M, Wieckowski MR, Pinton P. Mitochondrial Ca(2+) Remodeling is a Prime Factor in Oncogenic Behavior. Front Oncol 2015; 5:143. [PMID: 26161362 PMCID: PMC4479728 DOI: 10.3389/fonc.2015.00143] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 06/11/2015] [Indexed: 12/30/2022] Open
Abstract
Cancer is sustained by defects in the mechanisms underlying cell proliferation, mitochondrial metabolism, and cell death. Mitochondrial Ca2+ ions are central to all these processes, serving as signaling molecules with specific spatial localization, magnitude, and temporal characteristics. Mutations in mtDNA, aberrant expression and/or regulation of Ca2+-handling/transport proteins and abnormal Ca2+-dependent relationships among the cytosol, endoplasmic reticulum, and mitochondria can cause the deregulation of mitochondrial Ca2+-dependent pathways that are related to these processes, thus determining oncogenic behavior. In this review, we propose that mitochondrial Ca2+ remodeling plays a pivotal role in shaping the oncogenic signaling cascade, which is a required step for cancer formation and maintenance. We will describe recent studies that highlight the importance of mitochondria in inducing pivotal “cancer hallmarks” and discuss possible tools to manipulate mitochondrial Ca2+ to modulate cancer survival.
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Affiliation(s)
- Alessandro Rimessi
- Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), Department of Morphology, Surgery and Experimental Medicine, University of Ferrara , Ferrara , Italy
| | - Simone Patergnani
- Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), Department of Morphology, Surgery and Experimental Medicine, University of Ferrara , Ferrara , Italy
| | - Massimo Bonora
- Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), Department of Morphology, Surgery and Experimental Medicine, University of Ferrara , Ferrara , Italy
| | - Mariusz R Wieckowski
- Department of Biochemistry, Nencki Institute of Experimental Biology , Warsaw , Poland
| | - Paolo Pinton
- Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), Department of Morphology, Surgery and Experimental Medicine, University of Ferrara , Ferrara , Italy
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621
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Yang H, Peng YF, Ni HM, Li Y, Shi YH, Ding WX, Fan J. Basal Autophagy and Feedback Activation of Akt Are Associated with Resistance to Metformin-Induced Inhibition of Hepatic Tumor Cell Growth. PLoS One 2015; 10:e0130953. [PMID: 26111001 PMCID: PMC4482411 DOI: 10.1371/journal.pone.0130953] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 05/27/2015] [Indexed: 11/18/2022] Open
Abstract
While accumulating evidence has shown that the use of the diabetic drug metformin may be beneficial against various tumors in some epidemiological studies, a few studies failed to show the same beneficial effects. The molecular and cellular mechanisms for these conflicting observations are not clear. In this study, we compared the inhibitory effects of cell growth by metformin on several hepatic tumor cell lines: SMMC-7721, HCC-97L, HCC-LM3 and HepG2. While metformin inhibited cell growth in all these cells, we found that SMMC-7721, HCC-97L and HCC-LM3 cells were more resistant than HepG2 cells. Mechanistically, we found that metformin inhibited mTOR in all these hepatic tumor cells. However, SMMC-7721 cells had higher levels of basal autophagy and mTORC2-mediated feedback activation of Akt than HepG2 cells, which may render SMMC-7721 cells to be more resistant to metformin-induced inhibition of cell growth. Similarly, HCC-97L and HCC-LM3 cells also had higher feedback activation of AKT than HepG2 cells, which may also account for their resistance to metformin-induced inhibition of cell growth. Therefore, the various basal autophagy and mTOR activity in different cancer cells may contribute to the controversial findings on the use of metformin in inhibition of cancers in humans.
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Affiliation(s)
- Hua Yang
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas, 66160, United States of America
| | - Yuan-Fei Peng
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Hong-Min Ni
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas, 66160, United States of America
| | - Yuan Li
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas, 66160, United States of America
| | - Ying-Hong Shi
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas, 66160, United States of America
- * E-mail: (WXD); (JF)
| | - Jia Fan
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- * E-mail: (WXD); (JF)
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622
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Enot DP, Niso-Santano M, Durand S, Chery A, Pietrocola F, Vacchelli E, Madeo F, Galluzzi L, Kroemer G. Metabolomic analyses reveal that anti-aging metabolites are depleted by palmitate but increased by oleate in vivo. Cell Cycle 2015; 14:2399-407. [PMID: 26098646 DOI: 10.1080/15384101.2015.1064206] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Recently, we reported that saturated and unsaturated fatty acids trigger autophagy through distinct signal transduction pathways. Saturated fatty acids like palmitate (PA) induce autophagic responses that rely on phosphatidylinositol 3-kinase, catalytic subunit type 3 (PIK3C3, best known as VPS34) and beclin 1 (BECN1). Conversely, unsaturated fatty acids like oleate (OL) promote non-canonical, PIK3C3- and BECN1-independent autophagy. Here, we explored the metabolic effects of autophagy-inducing doses of PA and OL in mice. Mass spectrometry coupled to principal component analysis revealed that PA and OL induce well distinguishable changes in circulating metabolites as well as in the metabolic profile of the liver, heart, and skeletal muscle. Importantly, PA (but not OL) causes the depletion of multiple autophagy-inhibitory amino acids in the liver. Conversely, OL (but not PA) increased the hepatic levels of nicotinamide adenine dinucleotide (NAD), an obligate co-factor for autophagy-stimulatory enzymes of the sirtuin family. Moreover, PA (but not OL) raised the concentrations of acyl-carnitines in the heart, a phenomenon that perhaps is linked to its cardiotoxicity. PA also depleted the liver from spermine and spermidine, 2 polyamines have been ascribed with lifespan-extending activity. The metabolic changes imposed by unsaturated and saturated fatty acids may contribute to their health-promoting and health-deteriorating effects, respectively.
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Affiliation(s)
- David P Enot
- a Equipe 11 labellisée Ligue contre le Cancer; Centre de Recherche des Cordeliers ; Paris , France
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623
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Steele S, Brunton J, Kawula T. The role of autophagy in intracellular pathogen nutrient acquisition. Front Cell Infect Microbiol 2015; 5:51. [PMID: 26106587 PMCID: PMC4460576 DOI: 10.3389/fcimb.2015.00051] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 05/26/2015] [Indexed: 01/01/2023] Open
Abstract
Following entry into host cells intracellular pathogens must simultaneously evade innate host defense mechanisms and acquire energy and anabolic substrates from the nutrient-limited intracellular environment. Most of the potential intracellular nutrient sources are stored within complex macromolecules that are not immediately accessible by intracellular pathogens. To obtain nutrients for proliferation, intracellular pathogens must compete with the host cell for newly-imported simple nutrients or degrade host nutrient storage structures into their constituent components (fatty acids, carbohydrates, and amino acids). It is becoming increasingly evident that intracellular pathogens have evolved a wide variety of strategies to accomplish this task. One recurrent microbial strategy is to exploit host degradative processes that break down host macromolecules into simple nutrients that the microbe can use. Herein we focus on how a subset of bacterial, viral, and eukaryotic pathogens leverage the host process of autophagy to acquire nutrients that support their growth within infected cells.
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Affiliation(s)
- Shaun Steele
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina Chapel Hill, NC, USA
| | - Jason Brunton
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina Chapel Hill, NC, USA
| | - Thomas Kawula
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina Chapel Hill, NC, USA
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624
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Abstract
Mitochondrial function is key for maintaining cellular health, while mitochondrial failure is associated with various pathologies, including inherited metabolic disorders and age-related diseases. In order to maintain mitochondrial quality, several pathways of mitochondrial quality control have evolved. These systems monitor mitochondrial integrity through antioxidants, DNA repair systems, and chaperones and proteases involved in the mitochondrial unfolded protein response. Additional regulation of mitochondrial function involves dynamic exchange of components through mitochondrial fusion and fission. Sustained stress induces a selective autophagy - termed mitophagy - and ultimately leads to apoptosis. Together, these systems form a network that acts on the molecular, organellar, and cellular level. In this review, we highlight how these systems are regulated in an integrated context- and time-dependent network of mitochondrial quality control that is implicated in healthy aging.
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Affiliation(s)
- Ntsiki M Held
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, the Netherlands
| | - Riekelt H Houtkooper
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, the Netherlands
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625
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Ponpuak M, Mandell MA, Kimura T, Chauhan S, Cleyrat C, Deretic V. Secretory autophagy. Curr Opin Cell Biol 2015; 35:106-16. [PMID: 25988755 DOI: 10.1016/j.ceb.2015.04.016] [Citation(s) in RCA: 356] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 12/20/2022]
Abstract
Autophagy, once viewed exclusively as a cytoplasmic auto-digestive process, has its less intuitive but biologically distinct non-degradative roles. One manifestation of these functions of the autophagic machinery is the process termed secretory autophagy. Secretory autophagy facilitates unconventional secretion of the cytosolic cargo such as leaderless cytosolic proteins, which unlike proteins endowed with the leader (N-terminal signal) peptides cannot enter the conventional secretory pathway normally operating via the endoplasmic reticulum and the Golgi apparatus. Secretory autophagy may also export more complex cytoplasmic cargo and help excrete particulate substrates. Autophagic machinery and autophagy as a process also affect conventional secretory pathways, including the constitutive and regulated secretion, as well as promote alternative routes for trafficking of integral membrane proteins to the plasma membrane. Thus, autophagy and autophagic factors are intimately intertwined at many levels with secretion and polarized sorting in eukaryotic cells.
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Affiliation(s)
- Marisa Ponpuak
- Department of Microbiology, Faculty of Science, Mahidol University, 272 Rama VI Road, Ratchathewi, Bangkok 10400, Thailand; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA
| | - Michael A Mandell
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA
| | - Tomonori Kimura
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA
| | - Santosh Chauhan
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA
| | - Cédric Cleyrat
- Department of Pathology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA
| | - Vojo Deretic
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud NE, Albuquerque, NM 87131, USA.
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626
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627
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Emerging strategies to effectively target autophagy in cancer. Oncogene 2015; 35:1-11. [PMID: 25893285 DOI: 10.1038/onc.2015.99] [Citation(s) in RCA: 196] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/18/2015] [Accepted: 02/18/2015] [Indexed: 02/07/2023]
Abstract
Autophagy serves a dichotomous role in cancer and recent advances have helped delineate the appropriate settings where inhibiting or promoting autophagy may confer therapeutic efficacy in patients. Our evolving understanding of the molecular machinery responsible for the tightly controlled regulation of this homeostatic mechanism has begun to bear fruit in the way of autophagy-oriented clinical trials and promising lead compounds to modulate autophagy for therapeutic benefit. In this manuscript we review the recent preclinical and clinical therapeutic strategies that involve autophagy modulation in cancer.
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628
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Jackson WT. Viruses and the autophagy pathway. Virology 2015; 479-480:450-6. [PMID: 25858140 DOI: 10.1016/j.virol.2015.03.042] [Citation(s) in RCA: 161] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 01/30/2015] [Accepted: 03/12/2015] [Indexed: 12/15/2022]
Abstract
Studies of the cellular autophagy pathway have exploded over the past twenty years. Now appreciated as a constitutive degradative mechanism that promotes cellular homeostasis, autophagy is also required for a variety of developmental processes, cellular stress responses, and immune pathways. Autophagy certainly acts as both an anti-viral and pro-viral pathway, and the roles of autophagy depend on the virus, the cell type, and the cellular environment. The goal of this review is to summarize, in brief, what we know so far about the relationship between autophagy and viruses, particularly for those who are not familiar with the field. With a massive amount of relevant published data, it is simply not possible to be comprehensive, or to provide a complete "parade of viruses", and apologies are offered to researchers whose work is not described herein. Rather, this review is organized around general themes regarding the relationship between autophagy and animal viruses.
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Affiliation(s)
- William T Jackson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53211, United States.
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629
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Galluzzi L, Pietrocola F, Bravo-San Pedro JM, Amaravadi RK, Baehrecke EH, Cecconi F, Codogno P, Debnath J, Gewirtz DA, Karantza V, Kimmelman A, Kumar S, Levine B, Maiuri MC, Martin SJ, Penninger J, Piacentini M, Rubinsztein DC, Simon HU, Simonsen A, Thorburn AM, Velasco G, Ryan KM, Kroemer G. Autophagy in malignant transformation and cancer progression. EMBO J 2015; 34:856-80. [PMID: 25712477 PMCID: PMC4388596 DOI: 10.15252/embj.201490784] [Citation(s) in RCA: 903] [Impact Index Per Article: 100.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/14/2015] [Accepted: 01/16/2015] [Indexed: 12/15/2022] Open
Abstract
Autophagy plays a key role in the maintenance of cellular homeostasis. In healthy cells, such a homeostatic activity constitutes a robust barrier against malignant transformation. Accordingly, many oncoproteins inhibit, and several oncosuppressor proteins promote, autophagy. Moreover, autophagy is required for optimal anticancer immunosurveillance. In neoplastic cells, however, autophagic responses constitute a means to cope with intracellular and environmental stress, thus favoring tumor progression. This implies that at least in some cases, oncogenesis proceeds along with a temporary inhibition of autophagy or a gain of molecular functions that antagonize its oncosuppressive activity. Here, we discuss the differential impact of autophagy on distinct phases of tumorigenesis and the implications of this concept for the use of autophagy modulators in cancer therapy.
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Affiliation(s)
- Lorenzo Galluzzi
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France Université Paris Descartes Sorbonne Paris Cité, Paris, France
| | - Federico Pietrocola
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - José Manuel Bravo-San Pedro
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - Ravi K Amaravadi
- Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Eric H Baehrecke
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Francesco Cecconi
- Cell Stress and Survival Unit, Danish Cancer Society Research Center, Copenhagen, Denmark IRCCS Fondazione Santa Lucia and Department of Biology University of Rome Tor Vergata, Rome, Italy
| | - Patrice Codogno
- Université Paris Descartes Sorbonne Paris Cité, Paris, France Institut Necker Enfants-Malades (INEM), Paris, France INSERM U1151, Paris, France CNRS UMR8253, Paris, France
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - David A Gewirtz
- Department of Pharmacology, Toxicology and Medicine, Virginia Commonwealth University, Richmond Virginia, VA, USA
| | | | - Alec Kimmelman
- Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Sharad Kumar
- Centre for Cancer Biology, University of South Australia, Adelaide, SA, Australia
| | - Beth Levine
- Center for Autophagy Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Maria Chiara Maiuri
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - Seamus J Martin
- Department of Genetics, Trinity College, The Smurfit Institute, Dublin, Ireland
| | - Josef Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Mauro Piacentini
- Department of Biology, University of Rome Tor Vergata, Rome, Italy National Institute for Infectious Diseases IRCCS 'Lazzaro Spallanzani', Rome, Italy
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Anne Simonsen
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Andrew M Thorburn
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Guillermo Velasco
- Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University of Madrid, Madrid, Spain Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - Kevin M Ryan
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Guido Kroemer
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Université Paris Descartes Sorbonne Paris Cité, Paris, France Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, Villejuif, France
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630
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Kroemer G, Bravo-San Pedro JM, Galluzzi L. Novel function of cytoplasmic p53 at the interface between mitochondria and the endoplasmic reticulum. Cell Death Dis 2015; 6:e1698. [PMID: 25789973 PMCID: PMC4385946 DOI: 10.1038/cddis.2015.70] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- G Kroemer
- 1] Equipe 11 labellisée Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [2] INSERM, U1138, Paris, France [3] Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France [4] Université Pierre et Marie Curie/Paris VI, Paris, France [5] Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, Paris, France [6] Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France
| | - J M Bravo-San Pedro
- 1] Equipe 11 labellisée Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [2] INSERM, U1138, Paris, France [3] Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France [4] Université Pierre et Marie Curie/Paris VI, Paris, France [5] Gustave Roussy Cancer Campus, Villejuif, France
| | - L Galluzzi
- 1] Equipe 11 labellisée Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [2] INSERM, U1138, Paris, France [3] Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France [4] Université Pierre et Marie Curie/Paris VI, Paris, France [5] Gustave Roussy Cancer Campus, Villejuif, France
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631
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BIX-01294-induced autophagy regulates elongation of primary cilia. Biochem Biophys Res Commun 2015; 460:428-33. [PMID: 25796328 DOI: 10.1016/j.bbrc.2015.03.050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Accepted: 03/10/2015] [Indexed: 01/10/2023]
Abstract
Previously, we showed that BIX-01294 treatment strongly activates autophagy. Although, the interplay between autophagy and ciliogenesis has been suggested, the role of autophagy in ciliogenesis is controversial and largely unknown. In this study, we investigated the effects of autophagy induced by BIX-01294 on the formation of primary cilia in human retinal pigmented epithelial (RPE) cells. Treatment of RPE cells with BIX-01294 caused strong elongation of the primary cilium and increased the number of ciliated cells, as well as autophagy activation. The elongated cilia in serum starved cultured cells were gradually decreased by re-feeding the cells with normal growth medium. However, the disassembly of cilia was blocked in the BIX-01294-treated cells. In addition, both genetic and chemical inhibition of autophagy suppressed BIX-01294-mediated ciliogenesis in RPE cells. Taken together, these results suggest that autophagy induced by BIX-01294 positively regulates the elongation of primary cilium.
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632
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Viscomi C, Bottani E, Zeviani M. Emerging concepts in the therapy of mitochondrial disease. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:544-57. [PMID: 25766847 DOI: 10.1016/j.bbabio.2015.03.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 02/15/2015] [Accepted: 03/02/2015] [Indexed: 01/07/2023]
Abstract
Mitochondrial disorders are an important group of genetic conditions characterized by impaired oxidative phosphorylation. Mitochondrial disorders come with an impressive variability of symptoms, organ involvement, and clinical course, which considerably impact the quality of life and quite often shorten the lifespan expectancy. Although the last 20 years have witnessed an exponential increase in understanding the genetic and biochemical mechanisms leading to disease, this has not resulted in the development of effective therapeutic approaches, amenable of improving clinical course and outcome of these conditions to any significant extent. Therapeutic options for mitochondrial diseases still remain focused on supportive interventions aimed at relieving complications. However, new therapeutic strategies have recently been emerging, some of which have shown potential efficacy at the pre-clinical level. This review will present the state of the art on experimental therapy for mitochondrial disorders.
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Affiliation(s)
- Carlo Viscomi
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
| | | | - Massimo Zeviani
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
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633
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Westermeier F, Navarro-Marquez M, López-Crisosto C, Bravo-Sagua R, Quiroga C, Bustamante M, Verdejo HE, Zalaquett R, Ibacache M, Parra V, Castro PF, Rothermel BA, Hill JA, Lavandero S. Defective insulin signaling and mitochondrial dynamics in diabetic cardiomyopathy. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1113-8. [PMID: 25686534 DOI: 10.1016/j.bbamcr.2015.02.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 01/21/2015] [Accepted: 02/08/2015] [Indexed: 12/20/2022]
Abstract
Diabetic cardiomyopathy (DCM) is a common consequence of longstanding type 2 diabetes mellitus (T2DM) and encompasses structural, morphological, functional, and metabolic abnormalities in the heart. Myocardial energy metabolism depends on mitochondria, which must generate sufficient ATP to meet the high energy demands of the myocardium. Dysfunctional mitochondria are involved in the pathophysiology of diabetic heart disease. A large body of evidence implicates myocardial insulin resistance in the pathogenesis of DCM. Recent studies show that insulin signaling influences myocardial energy metabolism by impacting cardiomyocyte mitochondrial dynamics and function under physiological conditions. However, comprehensive understanding of molecular mechanisms linking insulin signaling and changes in the architecture of the mitochondrial network in diabetic cardiomyopathy is lacking. This review summarizes our current understanding of how defective insulin signaling impacts cardiac function in diabetic cardiomyopathy and discusses the potential role of mitochondrial dynamics.
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Affiliation(s)
- Francisco Westermeier
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Mario Navarro-Marquez
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Camila López-Crisosto
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Roberto Bravo-Sagua
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Clara Quiroga
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Mario Bustamante
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Hugo E Verdejo
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Ricardo Zalaquett
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Mauricio Ibacache
- Anesthesiology Division, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Valentina Parra
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile; Internal Medicine Division of Cardiology, Dallas, TX, USA; Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Pablo F Castro
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Beverly A Rothermel
- Internal Medicine Division of Cardiology, Dallas, TX, USA; Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joseph A Hill
- Internal Medicine Division of Cardiology, Dallas, TX, USA; Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile; Internal Medicine Division of Cardiology, Dallas, TX, USA; Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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634
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Cheong H. Integrating autophagy and metabolism in cancer. Arch Pharm Res 2015; 38:358-71. [PMID: 25614051 DOI: 10.1007/s12272-015-0562-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/12/2015] [Indexed: 02/06/2023]
Abstract
Autophagy is a catabolic process mediated by lysosomal degradation and is a key player in regulating cellular metabolism during cancer progression. Autophagy maintains cellular homeostasis by degrading unnecessary cellular molecules, which also prevents tumorigenesis. Conversely, autophagy also provides nutrients that support malignant tumor growth in advanced tumors. Multiple novel mechanisms have been proposed to explain the tumor-facilitating role of autophagy. Autophagy regulates diverse metabolic pathways that promote tumor proliferation and survival, which are closely associated with oncogenic activators and tumor suppressors. Autophagy has been implicated in cancer cell invasion and metastasis. Accordingly, autophagy has emerged as a tumor-promoting mechanism that facilitates cancer cell growth and survival. Mechanistic studies of autophagy during tumor progression may identify potential targets that can be utilized to disrupt cancer development. Understanding the molecular networks integrating metabolic changes and autophagy in cancer cells could provide novel insights to enhance targeted cancer therapies.
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Affiliation(s)
- Heesun Cheong
- Comparative Biomedicine Research Branch, Division of Cancer Biology, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi-do, 410-769, Republic of Korea,
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635
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Fafournoux P, Averous J, Bruhat A, Carraro V, Jousse C, Maurin AC, Mesclon F, Parry L. [Adaptation to the availability of essential amino-acids: role of GCN2/eIF2α/ATF4 pathway]. Biol Aujourdhui 2015; 209:317-23. [PMID: 27021050 DOI: 10.1051/jbio/2016005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Indexed: 11/14/2022]
Abstract
In mammals, metabolic adaptations are required to overcome nutritional deprivation in amino-acids/proteins as well as episodes of malnutrition. GCN2 protein kinase, which phosphorylates the α subunit of the translation initiation factor eIF2, is a sensor of amino-acid(s) deficiencies. On one hand, this review briefly describes the main features of amino-acid metabolism. On the other hand, it describes the role of GCN2 in regulating numerous physiological functions.
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