301
|
Weng TY, Tsai SYA, Su TP. Roles of sigma-1 receptors on mitochondrial functions relevant to neurodegenerative diseases. J Biomed Sci 2017; 24:74. [PMID: 28917260 PMCID: PMC5603014 DOI: 10.1186/s12929-017-0380-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022] Open
Abstract
The sigma-1 receptor (Sig-1R) is a chaperone that resides mainly at the mitochondrion-associated endoplasmic reticulum (ER) membrane (called the MAMs) and acts as a dynamic pluripotent modulator in living systems. At the MAM, the Sig-1R is known to play a role in regulating the Ca2+ signaling between ER and mitochondria and in maintaining the structural integrity of the MAM. The MAM serves as bridges between ER and mitochondria regulating multiple functions such as Ca2+ transfer, energy exchange, lipid synthesis and transports, and protein folding that are pivotal to cell survival and defense. Recently, emerging evidences indicate that the MAM is critical in maintaining neuronal homeostasis. Thus, given the specific localization of the Sig-1R at the MAM, we highlight and propose that the direct or indirect regulations of the Sig-1R on mitochondrial functions may relate to neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS). In addition, the promising use of Sig-1R ligands to rescue mitochondrial dysfunction-induced neurodegeneration is addressed.
Collapse
Affiliation(s)
- Tzu-Yu Weng
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, DHHS, IRP, NIDA/NIH, Triad Bldg. suite 3512, 333 Cassell Drive, Baltimore, MD 21224 USA
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Shang-Yi Anne Tsai
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, DHHS, IRP, NIDA/NIH, Triad Bldg. suite 3512, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, DHHS, IRP, NIDA/NIH, Triad Bldg. suite 3512, 333 Cassell Drive, Baltimore, MD 21224 USA
| |
Collapse
|
302
|
The Role of Mitochondria in the Activation/Maintenance of SOCE: Membrane Contact Sites as Signaling Hubs Sustaining Store-Operated Ca2+ Entry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:277-296. [DOI: 10.1007/978-3-319-57732-6_15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
|
303
|
The ER-Localized Transmembrane Protein EPG-3/VMP1 Regulates SERCA Activity to Control ER-Isolation Membrane Contacts for Autophagosome Formation. Mol Cell 2017; 67:974-989.e6. [PMID: 28890335 DOI: 10.1016/j.molcel.2017.08.005] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/23/2017] [Accepted: 08/08/2017] [Indexed: 01/27/2023]
Abstract
During autophagosome formation in mammalian cells, isolation membranes (IMs; autophagosome precursors) dynamically contact the ER. Here, we demonstrated that the ER-localized metazoan-specific autophagy protein EPG-3/VMP1 controls ER-IM contacts. Loss of VMP1 causes stable association of IMs with the ER, thus blocking autophagosome formation. Interaction of WIPI2 with the ULK1/FIP200 complex and PI(3)P contributes to the formation of ER-IM contacts, and these interactions are enhanced by VMP1 depletion. VMP1 controls contact formation by promoting SERCA (sarco[endo]plasmic reticulum calcium ATPase) activity. VMP1 interacts with SERCA and prevents formation of the SERCA/PLN/SLN inhibitory complex. VMP1 also modulates ER contacts with lipid droplets, mitochondria, and endosomes. These ER contacts are greatly elevated by the SERCA inhibitor thapsigargin. Calmodulin acts as a sensor/effector to modulate the ER contacts mediated by VMP1/SERCA. Our study provides mechanistic insights into the establishment and disassociation of ER-IM contacts and reveals that VMP1 modulates SERCA activity to control ER contacts.
Collapse
|
304
|
Carreras-Sureda A, Pihán P, Hetz C. Calcium signaling at the endoplasmic reticulum: fine-tuning stress responses. Cell Calcium 2017; 70:24-31. [PMID: 29054537 DOI: 10.1016/j.ceca.2017.08.004] [Citation(s) in RCA: 219] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 08/11/2017] [Accepted: 08/11/2017] [Indexed: 01/21/2023]
Abstract
Endoplasmic reticulum (ER) calcium signaling is implicated in a myriad of coordinated cellular processes. The ER calcium content is tightly regulated as it allows a favorable environment for protein folding, in addition to operate as a major reservoir for fast and specific release of calcium. Altered ER homeostasis impacts protein folding, activating the unfolded protein response (UPR) as a rescue mechanism to restore proteostasis. ER calcium release impacts mitochondrial metabolism and also fine-tunes the threshold to undergo apoptosis under chronic stress. The global coordination between UPR signaling and energetic demands takes place at mitochondrial associated membranes (MAMs), specialized subdomains mediating interorganelle communication. Here we discuss current models explaining the functional relationship between ER homeostasis and various cellular responses to coordinate proteostasis and metabolic maintenance.
Collapse
Affiliation(s)
- Amado Carreras-Sureda
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Chile; Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Philippe Pihán
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Chile; Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Chile; Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Buck Institute for Research on Aging, Novato, CA, 94945, USA; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
| |
Collapse
|
305
|
Bootman MD, Chehab T, Bultynck G, Parys JB, Rietdorf K. The regulation of autophagy by calcium signals: Do we have a consensus? Cell Calcium 2017; 70:32-46. [PMID: 28847414 DOI: 10.1016/j.ceca.2017.08.005] [Citation(s) in RCA: 193] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/14/2017] [Accepted: 08/14/2017] [Indexed: 12/12/2022]
Abstract
Macroautophagy (hereafter called 'autophagy') is a cellular process for degrading and recycling cellular constituents, and for maintenance of cell function. Autophagy initiates via vesicular engulfment of cellular materials and culminates in their degradation via lysosomal hydrolases, with the whole process often being termed 'autophagic flux'. Autophagy is a multi-step pathway requiring the interplay of numerous scaffolding and signalling molecules. In particular, orthologs of the family of ∼30 autophagy-regulating (Atg) proteins that were first characterised in yeast play essential roles in the initiation and processing of autophagic vesicles in mammalian cells. The serine/threonine kinase mTOR (mechanistic target of rapamycin) is a master regulator of the canonical autophagic response of cells to nutrient starvation. In addition, AMP-activated protein kinase (AMPK), which is a key sensor of cellular energy status, can trigger autophagy by inhibiting mTOR, or by phosphorylating other downstream targets. Calcium (Ca2+) has been implicated in autophagic signalling pathways encompassing both mTOR and AMPK, as well as in autophagy seemingly not involving these kinases. Numerous studies have shown that cytosolic Ca2+ signals can trigger autophagy. Moreover, introduction of an exogenous chelator to prevent cytosolic Ca2+ signals inhibits autophagy in response to many different stimuli, with suggestions that buffering Ca2+ affects not only the triggering of autophagy, but also proximal and distal steps during autophagic flux. Observations such as these indicate that Ca2+ plays an essential role as a pro-autophagic signal. However, cellular Ca2+ signals can exert anti-autophagic actions too. For example, Ca2+ channel blockers induce autophagy due to the loss of autophagy-suppressing Ca2+ signals. In addition, the sequestration of Ca2+ by mitochondria during physiological signalling appears necessary to maintain cellular bio-energetics, thereby suppressing AMPK-dependent autophagy. This article attempts to provide an integrated overview of the evidence for the proposed roles of various Ca2+ signals, Ca2+ channels and Ca2+ sources in controlling autophagic flux.
Collapse
Affiliation(s)
- Martin D Bootman
- School of Life, Health and Chemical Sciences, The Open University, MK7 6AA, UK.
| | - Tala Chehab
- School of Life, Health and Chemical Sciences, The Open University, MK7 6AA, UK
| | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), B-3000 Leuven, Belgium
| | - Jan B Parys
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), B-3000 Leuven, Belgium
| | - Katja Rietdorf
- School of Life, Health and Chemical Sciences, The Open University, MK7 6AA, UK
| |
Collapse
|
306
|
van Vliet AR, Garg AD, Agostinis P. Coordination of stress, Ca2+, and immunogenic signaling pathways by PERK at the endoplasmic reticulum. Biol Chem 2017; 397:649-56. [PMID: 26872313 DOI: 10.1515/hsz-2016-0108] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/08/2016] [Indexed: 12/17/2022]
Abstract
The endoplasmic reticulum (ER) is the main coordinator of intracellular Ca2+ signaling, protein synthesis, and folding. The ER is also implicated in the formation of contact sites with other organelles and structures, including mitochondria, plasma membrane (PM), and endosomes, thereby orchestrating through interorganelle signaling pathways, a variety of cellular responses including Ca2+ homeostasis, metabolism, and cell death signaling. Upon loss of its folding capacity, incited by a number of stress signals including those elicited by various anticancer therapies, the unfolded protein response (UPR) is launched to restore ER homeostasis. The ER stress sensor protein kinase RNA-like ER kinase (PERK) is a key mediator of the UPR and its role during ER stress has been largely recognized. However, growing evidence suggests that PERK may govern signaling pathways through UPR-independent functions. Here, we discuss emerging noncanonical roles of PERK with particular relevance for the induction of danger or immunogenic signaling and interorganelle communication.
Collapse
|
307
|
Rieusset J. Mitochondria-associated membranes (MAMs): An emerging platform connecting energy and immune sensing to metabolic flexibility. Biochem Biophys Res Commun 2017. [PMID: 28647358 DOI: 10.1016/j.bbrc.2017.06.097] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Living organisms have the capacity to sense both nutrients and immune signals in order to adapt their metabolism to the needs, and both metabolic inflexibility and exacerbated immune responses are associated with metabolic diseases. Over the past decade, mitochondria emerged as key nutrient and immune sensors regulating numerous signalling pathways, and mitochondria dysfunction has been extensively implicated in metabolic diseases. Interestingly, mitochondria interact physically and functionally with the endoplasmic reticulum (ER, in contact sites named mitochondria-associated membranes (MAMs), in order to exchange metabolites and calcium and regulate cellular homeostasis. Emerging evidences suggest that MAMs provide a platform for hormone and nutrient signalling pathways and for innate immune responses, then regulating mitochondrial bioenergetics and apoptosis. Here, I thus propose the concept that MAMs could be attractive nutrient and immune sensors that regulate mitochondria physiology in order to adapt metabolism and cell fate, and that organelle miscommunication could be involved in the metabolic inflexibility and the pro-inflammatory status associated with metabolic diseases.
Collapse
Affiliation(s)
- Jennifer Rieusset
- Laboratoire CarMeN, INSERM U1060, INRA U1235, Université Claude Bernard Lyon1, INSA-Lyon, F-69600 Oullins, France.
| |
Collapse
|
308
|
ER Stress and Autophagy in Obesity and Nonalcoholic Fatty Liver Disease. CURRENT PATHOBIOLOGY REPORTS 2017. [DOI: 10.1007/s40139-017-0145-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
309
|
Gutiérrez T, Simmen T. Endoplasmic reticulum chaperones tweak the mitochondrial calcium rheostat to control metabolism and cell death. Cell Calcium 2017; 70:64-75. [PMID: 28619231 DOI: 10.1016/j.ceca.2017.05.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/24/2017] [Accepted: 05/24/2017] [Indexed: 12/16/2022]
Abstract
The folding of secretory proteins is a well-understood mechanism, based on decades of research on endoplasmic reticulum (ER) chaperones. These chaperones interact with newly imported polypeptides close to the ER translocon. Classic examples for these proteins include the immunoglobulin binding protein (BiP/GRP78), and the lectins calnexin and calreticulin. Although not considered chaperones per se, the ER oxidoreductases of the protein disulfide isomerase (PDI) family complete the folding job by catalyzing the formation of disulfide bonds through cysteine oxidation. Research from the past decade has demonstrated that ER chaperones are multifunctional proteins. The regulation of ER-mitochondria Ca2+ crosstalk is one of their additional functions, as shown for calnexin, BiP/GRP78 or the oxidoreductases Ero1α and TMX1. This function depends on interactions of this group of proteins with the ER Ca2+ handling machinery. This novel function makes perfect sense for two reasons: i. It allows ER chaperones to control mitochondrial apoptosis instantly without a lengthy bypass involving the upregulation of pro-apoptotic transcription factors via the unfolded protein response (UPR); and ii. It allows the ER protein folding machinery to fine-tune ATP import via controlling the speed of mitochondrial oxidative phosphorylation. Therefore, the role of ER chaperones in regulating ER-mitochondria Ca2+ flux identifies the progression of secretory protein folding as a central regulator of cell survival and death, at least in cell types that secrete large amount of proteins. In other cell types, ER protein folding might serve as a sentinel mechanism that monitors cellular well-being to control cell metabolism and apoptosis. The selenoprotein SEPN1 is a classic example for such a role. Through the control of ER-mitochondria Ca2+-flux, ER chaperones and folding assistants guide cellular apoptosis and mitochondrial metabolism.
Collapse
Affiliation(s)
- Tomas Gutiérrez
- Faculty of Medicine and Dentistry, Department of Cell Biology, University of Alberta, Edmonton, T6G2H7, Canada
| | - Thomas Simmen
- Faculty of Medicine and Dentistry, Department of Cell Biology, University of Alberta, Edmonton, T6G2H7, Canada,.
| |
Collapse
|
310
|
Herrera-Cruz MS, Simmen T. Cancer: Untethering Mitochondria from the Endoplasmic Reticulum? Front Oncol 2017; 7:105. [PMID: 28603693 PMCID: PMC5445141 DOI: 10.3389/fonc.2017.00105] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/05/2017] [Indexed: 01/18/2023] Open
Abstract
Following the discovery of the mitochondria-associated membrane (MAM) as a hub for lipid metabolism in 1990 and its description as one of the first examples for membrane contact sites at the turn of the century, the past decade has seen the emergence of this structure as a potential regulator of cancer growth and metabolism. The mechanistic basis for this hypothesis is that the MAM accommodates flux of Ca2+ from the endoplasmic reticulum (ER) to mitochondria. This flux then determines mitochondrial ATP production, known to be low in many tumors as part of the Warburg effect. However, low mitochondrial Ca2+ flux also reduces the propensity of tumor cells to undergo apoptosis, another cancer hallmark. Numerous regulators of this flux have been recently identified as MAM proteins. Not surprisingly, many fall into the groups of tumor suppressors and oncogenes. Given the important role that the MAM could play in cancer, it is expected that proteins mediating its formation are particularly implicated in tumorigenesis. Examples for such proteins are mitofusin-2 and phosphofurin acidic cluster sorting protein 2 that likely act as tumor suppressors. This review discusses how these proteins that mediate or regulate ER–mitochondria tethering are (or are not) promoting or inhibiting tumorigenesis. The emerging picture of MAMs in cancer seems to indicate that in addition to the downregulation of mitochondrial Ca2+ import, MAM defects are but one way how cancer cells control mitochondria metabolism and apoptosis.
Collapse
Affiliation(s)
- Maria Sol Herrera-Cruz
- Faculty of Medicine and Dentistry, Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Thomas Simmen
- Faculty of Medicine and Dentistry, Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
311
|
Pendin D, Filadi R, Pizzo P. The Concerted Action of Mitochondrial Dynamics and Positioning: New Characters in Cancer Onset and Progression. Front Oncol 2017; 7:102. [PMID: 28589083 PMCID: PMC5439081 DOI: 10.3389/fonc.2017.00102] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/02/2017] [Indexed: 12/14/2022] Open
Abstract
Mitochondria are dynamic organelles whose morphology and activity are extremely variable, depending on the metabolic state of the cell. In particular, their shape and movements within the cell are finely regulated by an increasing number of proteins, which take part in the process of mitochondrial fission/fusion and connect the organelles to the cytoskeleton. As to their activities, mitochondria are considered to be at the crossroad between cell life and death since, on the one hand, they are essential in ATP production and in multiple metabolic pathways but, on the other, they are involved in the intrinsic apoptotic cascade, triggered by different stress conditions. Importantly, the process of mitochondrial Ca2+ uptake, as well as the morphology and the dynamics of these organelles, is known to deeply impact on both pro-survival and pro-death mitochondrial activities. Recently, increasing evidence has accrued on a central role of deregulated mitochondrial functionalities in the onset and progression of different pathologies, ranging from neurodegenerative diseases to cancer. In this contribution, we will present the latest findings connecting alterations in the machineries that control mitochondrial dynamics and localization to specific cancer hallmarks, highlighting the importance of mitochondria for the viability of cancer cells and discussing their role as promising targets for the development of novel anticancer therapies.
Collapse
Affiliation(s)
- Diana Pendin
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Neuroscience Institute, National Research Council (CNR), Padova, Italy
| |
Collapse
|
312
|
TSA protects H9c2 cells against thapsigargin-induced apoptosis related to endoplasmic reticulum stress-mediated mitochondrial injury. Saudi Pharm J 2017; 25:595-600. [PMID: 28579897 PMCID: PMC5447435 DOI: 10.1016/j.jsps.2017.04.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Endoplasmic reticulum stress (ERS) activates an adaptive unfolded protein response (UPR) that facilitates cellular repair, however, under prolonged ER stress, the UPR can ultimately trigger apoptosis thereby terminating damaged cells. Recently, TSA has shown protective effects on ERS and its mechanisms related to ER pathway has been previously characterized. However, whether TSA exerts its protective role via metabolic events remain largely undefined. Objectives: To explore the possible involvement of the metabolic changes during ERS and to better understand how TSA influence mitochondrial function to facilitate cellular adaptation. Results: TSA is an inhibitor of histone deacetylase which could significantly inhibit H9c2 cell apoptosis induced by Thapsigargin (TG). It also intervene the decrease of mitochondrial membrane potential. By immunofluorescence staining, we have shown that GRP78 was concentrated in the perinuclear region and co-localized with ER. However, treatments with TG and TSA could let it overlap with the mitochondrial marker MitoTracker. Cellular fractionation also confirmed the location of GRP78 in mitochondrion. CONCLUSIONS TSA decreases ERS-induced cell apoptosis and mitochondrial injury may related to enhance the location of GRP78 in mitochondrion.
Collapse
|
313
|
Marchi S, Patergnani S, Missiroli S, Morciano G, Rimessi A, Wieckowski MR, Giorgi C, Pinton P. Mitochondrial and endoplasmic reticulum calcium homeostasis and cell death. Cell Calcium 2017; 69:62-72. [PMID: 28515000 DOI: 10.1016/j.ceca.2017.05.003] [Citation(s) in RCA: 468] [Impact Index Per Article: 58.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 05/04/2017] [Accepted: 05/04/2017] [Indexed: 12/12/2022]
Abstract
The endoplasmic reticulum (ER) and mitochondria cannot be considered as static structures, as they intimately communicate, forming very dynamic platforms termed mitochondria-associated membranes (MAMs). In particular, the ER transmits proper Ca2+ signals to mitochondria, which decode them into specific inputs to regulate essential functions, including metabolism, energy production and apoptosis. Here, we will describe the different molecular players involved in the transfer of Ca2+ ions from the ER lumen to the mitochondrial matrix and how modifications in both ER-mitochondria contact sites and Ca2+ signaling can alter the cell death execution program.
Collapse
Affiliation(s)
- Saverio Marchi
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Simone Patergnani
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Sonia Missiroli
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Giampaolo Morciano
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Alessandro Rimessi
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | | | - Carlotta Giorgi
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Paolo Pinton
- Dept. of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy.
| |
Collapse
|
314
|
Teng RJ, Jing X, Michalkiewicz T, Afolayan AJ, Wu TJ, Konduri GG. Attenuation of endoplasmic reticulum stress by caffeine ameliorates hyperoxia-induced lung injury. Am J Physiol Lung Cell Mol Physiol 2017; 312:L586-L598. [PMID: 28213471 PMCID: PMC5451596 DOI: 10.1152/ajplung.00405.2016] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 02/09/2017] [Accepted: 02/10/2017] [Indexed: 12/17/2022] Open
Abstract
Rodent pups exposed to hyperoxia develop lung changes similar to bronchopulmonary dysplasia (BPD) in extremely premature infants. Oxidative stress from hyperoxia can injure developing lungs through endoplasmic reticulum (ER) stress. Early caffeine treatment decreases the rate of BPD, but the mechanisms remain unclear. We hypothesized that caffeine attenuates hyperoxia-induced lung injury through its chemical chaperone property. Sprague-Dawley rat pups were raised either in 90 (hyperoxia) or 21% (normoxia) oxygen from postnatal day 1 (P1) to postnatal day 10 (P10) and then recovered in 21% oxygen until P21. Caffeine (20 mg/kg) or normal saline (control) was administered intraperitoneally daily starting from P2. Lungs were inflation-fixed for histology or snap-frozen for immunoblots. Blood caffeine levels were measured in treated pups at euthanasia and were found to be 18.4 ± 4.9 μg/ml. Hyperoxia impaired alveolar formation and increased ER stress markers and downstream effectors; caffeine treatment attenuated these changes at P10. Caffeine also attenuated the hyperoxia-induced activation of cyclooxygenase-2 and markers of apoptosis. In conclusion, hyperoxia-induced alveolar growth impairment is mediated, in part, by ER stress. Early caffeine treatment protects developing lungs from hyperoxia-induced injury by attenuating ER stress.
Collapse
Affiliation(s)
- Ru-Jeng Teng
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| | - Xigang Jing
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| | - Teresa Michalkiewicz
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| | - Adeleye J Afolayan
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| | - Tzong-Jin Wu
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| | - Girija G Konduri
- Division of Neonatology, Department of Pediatrics, Medical College of Wisconsin, Wauwatosa, Wisconsin
| |
Collapse
|
315
|
Aouacheria A, Baghdiguian S, Lamb HM, Huska JD, Pineda FJ, Hardwick JM. Connecting mitochondrial dynamics and life-or-death events via Bcl-2 family proteins. Neurochem Int 2017; 109:141-161. [PMID: 28461171 DOI: 10.1016/j.neuint.2017.04.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 04/17/2017] [Indexed: 12/12/2022]
Abstract
The morphology of a population of mitochondria is the result of several interacting dynamical phenomena, including fission, fusion, movement, elimination and biogenesis. Each of these phenomena is controlled by underlying molecular machinery, and when defective can cause disease. New understanding of the relationships between form and function of mitochondria in health and disease is beginning to be unraveled on several fronts. Studies in mammals and model organisms have revealed that mitochondrial morphology, dynamics and function appear to be subject to regulation by the same proteins that regulate apoptotic cell death. One protein family that influences mitochondrial dynamics in both healthy and dying cells is the Bcl-2 protein family. Connecting mitochondrial dynamics with life-death pathway forks may arise from the intersection of Bcl-2 family proteins with the proteins and lipids that determine mitochondrial shape and function. Bcl-2 family proteins also have multifaceted influences on cells and mitochondria, including calcium handling, autophagy and energetics, as well as the subcellular localization of mitochondrial organelles to neuronal synapses. The remarkable range of physical or functional interactions by Bcl-2 family proteins is challenging to assimilate into a cohesive understanding. Most of their effects may be distinct from their direct roles in apoptotic cell death and are particularly apparent in the nervous system. Dual roles in mitochondrial dynamics and cell death extend beyond BCL-2 family proteins. In this review, we discuss many processes that govern mitochondrial structure and function in health and disease, and how Bcl-2 family proteins integrate into some of these processes.
Collapse
Affiliation(s)
- Abdel Aouacheria
- Institute of Evolutionary Sciences of Montpellier (ISEM), CNRS UMR 5554, University of Montpellier, Place Eugène Bataillon, 34095 Montpellier, France
| | - Stephen Baghdiguian
- Institute of Evolutionary Sciences of Montpellier (ISEM), CNRS UMR 5554, University of Montpellier, Place Eugène Bataillon, 34095 Montpellier, France
| | - Heather M Lamb
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205, USA
| | - Jason D Huska
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205, USA
| | - Fernando J Pineda
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205, USA; Department of Biostatistics, Johns Hopkins University, Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205, USA
| | - J Marie Hardwick
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205, USA.
| |
Collapse
|
316
|
Harada N, Okuyama M, Yoshikatsu A, Yamamoto H, Ishiwata S, Hamada C, Hirose T, Shono M, Kuroda M, Tsutsumi R, Takeo J, Taketani Y, Nakaya Y, Sakaue H. Endoplasmic Reticulum Stress in Mice Increases Hepatic Expression of Genes Carrying a Premature Termination Codon via a Nutritional Status‐Independent GRP78‐Dependent Mechanism. J Cell Biochem 2017; 118:3810-3824. [DOI: 10.1002/jcb.26031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/04/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Nagakatsu Harada
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Maiko Okuyama
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Aya Yoshikatsu
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Hironori Yamamoto
- Faculty of Human LifeDepartment of Health and NutritionJin‐ai University3‐1‐1 Ohde‐choEchizen City915‐8586Japan
| | - Saori Ishiwata
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Chikako Hamada
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Tomoyo Hirose
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Masayuki Shono
- Support Center for Advanced Medical SciencesInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Masashi Kuroda
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Rie Tsutsumi
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Jiro Takeo
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
- Central Research LaboratoryNippon Suisan Kaisha32‐3 Nanakuni 1 ChomeHachiojiTokyo192‐0991Japan
| | - Yutaka Taketani
- Department of Clinical Nutrition and Food ManagementInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Yutaka Nakaya
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Hiroshi Sakaue
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| |
Collapse
|
317
|
DR5 and caspase-8 are dispensable in ER stress-induced apoptosis. Cell Death Differ 2017; 24:944-950. [PMID: 28409774 DOI: 10.1038/cdd.2017.53] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 02/28/2017] [Accepted: 03/17/2017] [Indexed: 12/21/2022] Open
Abstract
The endoplasmic reticulum (ER) stress response constitutes cellular reactions triggered by a wide variety of stimuli that disturb folding of proteins, often leading to apoptosis. ER stress-induced apoptotic cell death is thought to be an important contributor to many human pathological conditions. The molecular mechanism of this apoptosis process has been highly controversial with both the receptor and the mitochondrial pathways being implicated. Using knockout mouse models and RNAi-mediated gene silencing in cell lines, our group and others had demonstrated the importance of the mitochondrial apoptotic pathway in ER stress-induced cell death, particularly the role of the pro-apoptotic BH3-only BCL-2 family members, BIM and PUMA. However, a recent report suggested a central role for the death receptor, DR5, activated in a ligand-independent manner, and the initiator caspase, caspase-8, in ER stress-induced cell death. This prompted us to re-visit our previous observations and attempt to reproduce the newly published findings. Here we report that the mitochondrial apoptotic pathway, activated by BH3-only proteins, is essential for ER stress-induced cell death and that, in contrast to the previous report, DR5 as well as caspase-8 are not required for this process.
Collapse
|
318
|
Carreras-Sureda A, Pihán P, Hetz C. The Unfolded Protein Response: At the Intersection between Endoplasmic Reticulum Function and Mitochondrial Bioenergetics. Front Oncol 2017; 7:55. [PMID: 28421160 PMCID: PMC5377016 DOI: 10.3389/fonc.2017.00055] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/13/2017] [Indexed: 02/04/2023] Open
Abstract
Endoplasmic reticulum (ER) to mitochondria communication has emerged in recent years as a signaling hub regulating cellular physiology with a relevant contribution to diseases including cancer and neurodegeneration. This functional integration is exerted through discrete interorganelle structures known as mitochondria-associated membranes (MAMs). At these domains, ER/mitochondria physically associate to dynamically adjust metabolic demands and the response to stress stimuli. Here, we provide a focused overview of how the ER shapes the function of the mitochondria, giving a special emphasis to the significance of local signaling of the unfolded protein response at MAMs. The implications to cell fate control and the progression of cancer are also discussed.
Collapse
Affiliation(s)
- Amado Carreras-Sureda
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile.,Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Philippe Pihán
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile.,Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile.,Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile.,Buck Institute for Research on Aging, Novato, CA, USA.,Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
| |
Collapse
|
319
|
Bravo-Sagua R, Parra V, López-Crisosto C, Díaz P, Quest AFG, Lavandero S. Calcium Transport and Signaling in Mitochondria. Compr Physiol 2017; 7:623-634. [PMID: 28333383 DOI: 10.1002/cphy.c160013] [Citation(s) in RCA: 175] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Calcium (Ca2+) is a key player in the regulation of many cell functions. Just like Ca2+, mitochondria are ubiquitous, versatile, and dynamic players in determining both cell survival and death decisions. Given their ubiquitous nature, the regulation of both is deeply intertwined, whereby Ca2+ regulates mitochondrial functions, while mitochondria shape Ca2+ dynamics. Deregulation of either Ca2+ or mitochondrial signaling leads to abnormal function, cell damage or even cell death, thereby contributing to muscle dysfunction or cardiac pathologies. Moreover, altered mitochondrial Ca2+ homeostasis has been linked to metabolic diseases like cancer, obesity, and pulmonary hypertension. In this review article, we summarize the mechanisms that coordinate mitochondrial and Ca2+ responses and how they affect human health. © 2017 American Physiological Society. Compr Physiol 7:623-634, 2017.
Collapse
Affiliation(s)
- Roberto Bravo-Sagua
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile.,Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago, Chile
| | - Valentina Parra
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Camila López-Crisosto
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Paula Díaz
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile
| | - Andrew F G Quest
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Molecular Studies of the Cell (CEMC), Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile, Santiago, Chile
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Molecular Studies of the Cell (CEMC), Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile, Santiago, Chile.,Cardiology Division, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|
320
|
Leishmania donovani chaperonin 10 regulates parasite internalization and intracellular survival in human macrophages. Med Microbiol Immunol 2017; 206:235-257. [PMID: 28283754 DOI: 10.1007/s00430-017-0500-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 02/21/2017] [Indexed: 12/15/2022]
Abstract
Protozoa of the genus Leishmania infect macrophages in their mammalian hosts causing a spectrum of diseases known as the leishmaniases. The search for leishmania effectors that support macrophage infection is a focus of significant interest. One such candidate is leishmania chaperonin 10 (CPN10) which is secreted in exosomes and may have immunosuppressive properties. Here, we report for the first time that leishmania CPN10 localizes to the cytosol of infected macrophages. Next, we generated two genetically modified strains of Leishmania donovani (Ld): one strain overexpressing CPN10 (CPN10+++) and the second, a CPN10 single allele knockdown (CPN10+/-), as the null mutant was lethal. When compared with the wild-type (WT) parental strain, CPN10+/- Ld showed higher infection rates and parasite loads in human macrophages after 24 h of infection. Conversely, CPN10+++ Ld was associated with lower initial infection rates. This unexpected apparent gain-of-function for the knockdown could have been explained either by enhanced parasite internalization or by enhanced intracellular survival. Paradoxically, we found that CPN10+/- leishmania were more readily internalized than WT Ld, but also displayed significantly impaired intracellular survival. This suggests that leishmania CPN10 negatively regulates the rate of parasite uptake by macrophages while being required for intracellular survival. Finally, quantitative proteomics identified an array of leishmania proteins whose expression was positively regulated by CPN10. In contrast, many macrophage proteins involved in innate immunity were negatively regulated by CPN10. Taken together, these findings identify leishmania CPN10 as a novel effector with broad based effects on macrophage cell regulation and parasite survival.
Collapse
|
321
|
Lopez-Crisosto C, Pennanen C, Vasquez-Trincado C, Morales PE, Bravo-Sagua R, Quest AFG, Chiong M, Lavandero S. Sarcoplasmic reticulum-mitochondria communication in cardiovascular pathophysiology. Nat Rev Cardiol 2017; 14:342-360. [PMID: 28275246 DOI: 10.1038/nrcardio.2017.23] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Repetitive, calcium-mediated contractile activity renders cardiomyocytes critically dependent on a sustained energy supply and adequate calcium buffering, both of which are provided by mitochondria. Moreover, in vascular smooth muscle cells, mitochondrial metabolism modulates cell growth and proliferation, whereas cytosolic calcium levels regulate the arterial vascular tone. Physical and functional communication between mitochondria and sarco/endoplasmic reticulum and balanced mitochondrial dynamics seem to have a critical role for optimal calcium transfer to mitochondria, which is crucial in calcium homeostasis and mitochondrial metabolism in both types of muscle cells. Moreover, mitochondrial dysfunction has been associated with myocardial damage and dysregulation of vascular smooth muscle proliferation. Therefore, sarco/endoplasmic reticulum-mitochondria coupling and mitochondrial dynamics are now viewed as relevant factors in the pathogenesis of cardiac and vascular diseases, including coronary artery disease, heart failure, and pulmonary arterial hypertension. In this Review, we summarize the evidence related to the role of sarco/endoplasmic reticulum-mitochondria communication in cardiac and vascular muscle physiology, with a focus on how perturbations contribute to the pathogenesis of cardiovascular disorders.
Collapse
Affiliation(s)
- Camila Lopez-Crisosto
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile
| | - Christian Pennanen
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile
| | - Cesar Vasquez-Trincado
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile
| | - Pablo E Morales
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile
| | - Roberto Bravo-Sagua
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile.,Instituto de Nutricion y Tecnologia de los Alimentos (INTA), Universidad de Chile, Avenida El Líbano 5524, Santiago 7830490, Chile
| | - Andrew F G Quest
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile.,Centro de Estudios Moleculares de la Celula (CEMC), Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 8380453, Chile
| | - Mario Chiong
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas &Facultad de Medicina, Universidad de Chile, Sergio Livingstone 1007, Santiago 8380492, Chile.,Centro de Estudios Moleculares de la Celula (CEMC), Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 8380453, Chile.,Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, Texas 75235, USA
| |
Collapse
|
322
|
Hepatic stimulator substance inhibits calcium overflow through the mitochondria-associated membrane compartment during nonalcoholic steatohepatitis. J Transl Med 2017; 97:289-301. [PMID: 27991906 DOI: 10.1038/labinvest.2016.139] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 10/26/2016] [Accepted: 11/17/2016] [Indexed: 12/14/2022] Open
Abstract
Nonalcoholic fatty liver disease is considered a disorder of the endoplasmic reticulum (ER) and mitochondria. Recent studies have shown that the ER and mitochondrial membranes overlap by 15-20%, a region referred to as the 'mitochondria-associated ER membrane' (MAM). Some proteins, including sarco/ER calcium ATPase (SERCA), are located in the MAM and have an important role in Ca2+ signaling and homeostasis between the ER and the mitochondria. Our previous study showed that hepatic stimulator substance (HSS) inhibits the ER stress induced by reactive oxygen species, thus reducing mitochondrial damage. However, the mechanism underlying the protective effect of HSS on the ER and ER-mitochondrial interaction remains unclear. In this study, we confirmed that the exogenous expression of HSS protected the liver from steatosis in mice with nonalcoholic steatohepatitis. More importantly, the protection provided by HSS allowed SERCA in the MAM compartment to function well, preventing the extensive influx of cytosolic free Ca2+ to the mitochondria, thus preserving the mitochondrial functions from calcium overload and relieving palmitic-acid-induced hepatocyte steatosis. Our results suggest that the protective effect of HSS on SERCA expression is associated with the maintenance of calcium homeostasis within the MAM, thus ameliorating the disordered Ca2+ communication between the ER and mitochondria.
Collapse
|
323
|
Tubbs E, Rieusset J. Metabolic signaling functions of ER-mitochondria contact sites: role in metabolic diseases. J Mol Endocrinol 2017; 58:R87-R106. [PMID: 27965371 DOI: 10.1530/jme-16-0189] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 12/13/2016] [Indexed: 12/16/2022]
Abstract
Beyond the maintenance of cellular homeostasis and the determination of cell fate, ER-mitochondria contact sites, defined as mitochondria-associated membranes (MAM), start to emerge as an important signaling hub that integrates nutrient and hormonal stimuli and adapts cellular metabolism. Here, we summarize the established structural and functional features of MAM and mainly focus on the latest breakthroughs highlighting a crucial role of organelle crosstalk in the control of metabolic homeostasis. Lastly, we discuss recent studies that have revealed the importance of MAM in not only metabolic diseases but also in other pathologies with disrupted metabolism, shedding light on potential common molecular mechanisms and leading hopefully to novel treatment strategies.
Collapse
Affiliation(s)
- Emily Tubbs
- Department of Clinical SciencesLund University Diabetes Centre, Malmö, Sweden
| | - Jennifer Rieusset
- INSERM UMR-1060CarMeN Laboratory, Lyon 1 University, INRA U1235, INSA of Lyon, Charles Merieux Lyon-Sud medical Universities, Lyon, France
| |
Collapse
|
324
|
De Mario A, Quintana-Cabrera R, Martinvalet D, Giacomello M. (Neuro)degenerated Mitochondria-ER contacts. Biochem Biophys Res Commun 2017; 483:1096-1109. [DOI: 10.1016/j.bbrc.2016.07.056] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 07/10/2016] [Indexed: 01/24/2023]
|
325
|
Herrera-Cruz MS, Simmen T. Of yeast, mice and men: MAMs come in two flavors. Biol Direct 2017; 12:3. [PMID: 28122638 PMCID: PMC5267431 DOI: 10.1186/s13062-017-0174-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/18/2017] [Indexed: 12/15/2022] Open
Abstract
The past decade has seen dramatic progress in our understanding of membrane contact sites (MCS). Important examples of these are endoplasmic reticulum (ER)-mitochondria contact sites. ER-mitochondria contacts have originally been discovered in mammalian tissue, where they have been designated as mitochondria-associated membranes (MAMs). It is also in this model system, where the first critical MAM proteins have been identified, including MAM tethering regulators such as phospho-furin acidic cluster sorting protein 2 (PACS-2) and mitofusin-2. However, the past decade has seen the discovery of the MAM also in the powerful yeast model system Saccharomyces cerevisiae. This has led to the discovery of novel MAM tethers such as the yeast ER-mitochondria encounter structure (ERMES), absent in the mammalian system, but whose regulators Gem1 and Lam6 are conserved. While MAMs, sometimes referred to as mitochondria-ER contacts (MERCs), regulate lipid metabolism, Ca2+ signaling, bioenergetics, inflammation, autophagy and apoptosis, not all of these functions exist in both systems or operate differently. This biological difference has led to puzzling discrepancies on findings obtained in yeast or mammalian cells at the moment. Our review aims to shed some light onto mechanistic differences between yeast and mammalian MAM and their underlying causes. Reviewers: This article was reviewed by Paola Pizzo (nominated by Luca Pellegrini), Maya Schuldiner and György Szabadkai (nominated by Luca Pellegrini).
Collapse
Affiliation(s)
- Maria Sol Herrera-Cruz
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, T6G2H7, Canada
| | - Thomas Simmen
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, T6G2H7, Canada.
| |
Collapse
|
326
|
Haile Y, Deng X, Ortiz-Sandoval C, Tahbaz N, Janowicz A, Lu JQ, Kerr BJ, Gutowski NJ, Holley JE, Eggleton P, Giuliani F, Simmen T. Rab32 connects ER stress to mitochondrial defects in multiple sclerosis. J Neuroinflammation 2017; 14:19. [PMID: 28115010 PMCID: PMC5260063 DOI: 10.1186/s12974-016-0788-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/29/2016] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Endoplasmic reticulum (ER) stress is a hallmark of neurodegenerative diseases such as multiple sclerosis (MS). However, this physiological mechanism has multiple manifestations that range from impaired clearance of unfolded proteins to altered mitochondrial dynamics and apoptosis. While connections between the triggering of the unfolded protein response (UPR) and downstream mitochondrial dysfunction are poorly understood, the membranous contacts between the ER and mitochondria, called the mitochondria-associated membrane (MAM), could provide a functional link between these two mechanisms. Therefore, we investigated whether the guanosine triphosphatase (GTPase) Rab32, a known regulator of the MAM, mitochondrial dynamics, and apoptosis, could be associated with ER stress as well as mitochondrial dysfunction. METHODS We assessed Rab32 expression in MS patient and experimental autoimmune encephalomyelitis (EAE) tissue, via observation of mitochondria in primary neurons and via monitoring of survival of neuronal cells upon increased Rab32 expression. RESULTS We found that the induction of Rab32 and other MAM proteins correlates with ER stress proteins in MS brain, as well as in EAE, and occurs in multiple central nervous system (CNS) cell types. We identify Rab32, known to increase in response to acute brain inflammation, as a novel unfolded protein response (UPR) target. High Rab32 expression shortens neurite length, alters mitochondria morphology, and accelerates apoptosis/necroptosis of human primary neurons and cell lines. CONCLUSIONS ER stress is strongly associated with Rab32 upregulation in the progression of MS, leading to mitochondrial dysfunction and neuronal death.
Collapse
Affiliation(s)
- Yohannes Haile
- Department of Cell Biology, University of Alberta, Edmonton, Canada.,Present address: Alberta Diabetes Institute, University of Alberta, Edmonton, Canada
| | - Xiaodan Deng
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Canada
| | | | - Nasser Tahbaz
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | | | - Jian-Qiang Lu
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Canada
| | - Bradley J Kerr
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Canada
| | - Nicholas J Gutowski
- University of Exeter Medical School & Neurology Department, Royal Devon & Exeter Hospital, Exeter, UK
| | - Janet E Holley
- University of Exeter Medical School & Neurology Department, Royal Devon & Exeter Hospital, Exeter, UK
| | - Paul Eggleton
- University of Exeter Medical School & Neurology Department, Royal Devon & Exeter Hospital, Exeter, UK
| | - Fabrizio Giuliani
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Canada.
| | - Thomas Simmen
- Department of Cell Biology, University of Alberta, Edmonton, Canada.
| |
Collapse
|
327
|
Bonetti A, Della Mora A, Contin M, Gregoraci G, Tubaro F, Marchini M, Ortolani F. Survival-Related Autophagic Activity Versus Procalcific Death in Cultured Aortic Valve Interstitial Cells Treated With Critical Normophosphatemic-Like Phosphate Concentrations. J Histochem Cytochem 2017; 65:125-138. [PMID: 28112549 PMCID: PMC5298459 DOI: 10.1369/0022155416687760] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Valve dystrophic calcification is a common disorder affecting normophosphatemic subjects. Here, cultured aortic valve interstitial cells (AVICs) were treated 3 to 28 days with phosphate (Pi) concentrations spanning the normal range in humans (0.8, 1.3, and 2.0 mM) alone or supplemented with proinflammatory stimuli to assess possible priming of dystrophic-like calcification. Compared with controls, spectrophotometric analyses revealed marked increases in calcium amounts and alkaline phosphatase activity for 2.0-mM-Pi-containing cultures, with enhancing by proinflammatory mediators. Ultrastructurally, AVICs treated with low/middle Pi concentrations showed an enormous endoplasmic reticulum (ER) enclosing organelle debris, so apparently executing a survival-related atypical macroautophagocytosis, consistently with ultracytochemical demonstration of ER-associated acid phosphatase activity and decreases in autophagosomes and immunodetectable MAP1LC3. In contrast, AVICs cultured at 2.0-mM Pi underwent mineralization due to intracellular release and peripheral layering of phospholipid-rich material acting as hydroxyapatite nucleator, as revealed by Cuprolinic Blue and von Kossa ultracytochemical reactions. Lack of immunoblotted caspase-3 cleaved form indicated apoptosis absence for all cultures. In conclusion, fates of cultured AVICs were crucially driven by Pi concentration, suggesting that serum Pi levels just below the upper limit of normophosphatemia in humans may represent a critical watershed between macroautophagy-associated cell restoring and procalcific cell death.
Collapse
Affiliation(s)
- Antonella Bonetti
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Alberto Della Mora
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Magali Contin
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Giorgia Gregoraci
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Franco Tubaro
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Maurizio Marchini
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| | - Fulvia Ortolani
- Departments of Experimental and Clinical Medicine (AB, ADM, MC, MM, FO), Medical and Biological Sciences (GG), and Agricultural, Food, Environmental and Animal Sciences (FT), University of Udine, Udine, Italy
| |
Collapse
|
328
|
van der Harg JM, van Heest JC, Bangel FN, Patiwael S, van Weering JRT, Scheper W. The UPR reduces glucose metabolism via IRE1 signaling. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:655-665. [PMID: 28093214 DOI: 10.1016/j.bbamcr.2017.01.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 12/31/2022]
Abstract
Neurons are highly dependent on glucose. A disturbance in glucose homeostasis therefore poses a severe risk that is counteracted by activation of stress responses to limit damage and restore the energy balance. A major stress response that is activated under conditions of glucose deprivation is the unfolded protein response (UPR) that is aimed to restore proteostasis in the endoplasmic reticulum. The key signaling of the UPR involves the transient activation of a transcriptional program and an overall reduction of protein synthesis. Since the UPR is strategically positioned to sense and integrate metabolic stress signals, it is likely that - apart from its adaptive response to restore proteostasis - it also directly affects metabolic pathways. Here we investigate the direct role of the UPR in glucose homeostasis. O-GlcNAc is a post-translational modification that is highly responsive to glucose fluctuations. We find that UPR activation results in decreased O-GlcNAc modification, in line with reduced glucose metabolism. Our data indicate that UPR activation has no direct impact on the upstream processes in glucose metabolism; glucose transporter expression, glucose uptake and hexokinase activity. In contrast, prolonged UPR activation decreases glycolysis and mitochondrial metabolism. Decreased mitochondrial respiration is not accompanied by apoptosis or a structural change in mitochondria indicating that the reduction in metabolic rate upon UPR activation is a physiological non-apoptotic response. Metabolic decrease is prevented if the IRE1 pathway of the UPR is inhibited. This indicates that activation of IRE1 signaling induces a reduction in glucose metabolism, as part of an adaptive response.
Collapse
Affiliation(s)
- Judith M van der Harg
- Dept. of Genome Analysis, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Dept. of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Jessica C van Heest
- Dept. of Genome Analysis, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Fabian N Bangel
- Dept. of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands; Dept. of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands
| | - Sanne Patiwael
- Dept. of Genome Analysis, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan R T van Weering
- Dept. of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands; Dept. of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands
| | - Wiep Scheper
- Dept. of Genome Analysis, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Dept. of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands; Dept. of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands; Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands.
| |
Collapse
|
329
|
Filadi R, Theurey P, Pizzo P. The endoplasmic reticulum-mitochondria coupling in health and disease: Molecules, functions and significance. Cell Calcium 2017; 62:1-15. [PMID: 28108029 DOI: 10.1016/j.ceca.2017.01.003] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/09/2017] [Accepted: 01/09/2017] [Indexed: 12/14/2022]
Abstract
The close apposition between endoplasmic reticulum (ER) and mitochondria represents a key platform, capable to regulate different fundamental cellular pathways. Among these, Ca2+ signaling and lipid homeostasis have been demonstrated over the last years to be deeply modulated by ER-mitochondria cross-talk. Given its importance in cell life/death decisions, increasing evidence suggests that alterations of the ER-mitochondria axis could be responsible for the onset and progression of several diseases, including neurodegeneration, cancer and obesity. However, the molecular identity of the proteins controlling this inter-organelle apposition is still debated. In this review, we summarize the main cellular pathways controlled by ER-mitochondria appositions, focusing on the principal molecules reported to be involved in this interplay and on those diseases for which alterations in organelles communication have been reported.
Collapse
Affiliation(s)
- Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Italy
| | - Pierre Theurey
- Department of Biomedical Sciences, University of Padova, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Italy; Neuroscience Institute, National Research Council (CNR), Padova, Italy.
| |
Collapse
|
330
|
Rieusset J. Endoplasmic reticulum-mitochondria calcium signaling in hepatic metabolic diseases. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:865-876. [PMID: 28064001 DOI: 10.1016/j.bbamcr.2017.01.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 12/21/2016] [Accepted: 01/02/2017] [Indexed: 02/07/2023]
Abstract
The liver plays a central role in glucose homeostasis, and both metabolic inflexibility and insulin resistance predispose to the development of hepatic metabolic diseases. Mitochondria and endoplasmic reticulum (ER), which play a key role in the control of hepatic metabolism, also interact at contact points defined as mitochondria-associated membranes (MAM), in order to exchange metabolites and calcium (Ca2+) and regulate cellular homeostasis and signaling. Here, we overview the role of the liver in the control of glucose homeostasis, mainly focusing on the independent involvement of mitochondria, ER and Ca2+ signaling in both healthy and pathological contexts. Then we focus on recent data highlighting MAM as important hubs for hormone and nutrient signaling in the liver, thus adapting mitochondria physiology and cellular metabolism to energy availability. Lastly, we discuss how chronic ER-mitochondria miscommunication could participate to hepatic metabolic diseases, pointing MAM interface as a potential therapeutic target for metabolic disorders. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
Collapse
Affiliation(s)
- Jennifer Rieusset
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1397, F-69921 Oullins, France.
| |
Collapse
|
331
|
Marchi S, Bittremieux M, Missiroli S, Morganti C, Patergnani S, Sbano L, Rimessi A, Kerkhofs M, Parys JB, Bultynck G, Giorgi C, Pinton P. Endoplasmic Reticulum-Mitochondria Communication Through Ca 2+ Signaling: The Importance of Mitochondria-Associated Membranes (MAMs). ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 997:49-67. [PMID: 28815521 DOI: 10.1007/978-981-10-4567-7_4] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The execution of proper Ca2+ signaling requires close apposition between the endoplasmic reticulum (ER) and mitochondria. Hence, Ca2+ released from the ER is "quasi-synaptically" transferred to mitochondrial matrix, where Ca2+ stimulates mitochondrial ATP synthesis by activating the tricarboxylic acid (TCA) cycle. However, when the Ca2+ transfer is excessive and sustained, mitochondrial Ca2+ overload induces apoptosis by opening the mitochondrial permeability transition pore. A large number of regulatory proteins reside at mitochondria-associated ER membranes (MAMs) to maintain the optimal distance between the organelles and to coordinate the functionality of both ER and mitochondrial Ca2+ transporters or channels. In this chapter, we discuss the different pathways involved in the regulation of ER-mitochondria Ca2+ flux and describe the activities of the various Ca2+ players based on their primary intra-organelle localization.
Collapse
Affiliation(s)
- Saverio Marchi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Mart Bittremieux
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut, KU Leuven, Campus Gasthuisberg O&N-I box 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Sonia Missiroli
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Claudia Morganti
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Simone Patergnani
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Luigi Sbano
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Alessandro Rimessi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Martijn Kerkhofs
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut, KU Leuven, Campus Gasthuisberg O&N-I box 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Jan B Parys
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut, KU Leuven, Campus Gasthuisberg O&N-I box 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Geert Bultynck
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut, KU Leuven, Campus Gasthuisberg O&N-I box 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Carlotta Giorgi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy.
| | - Paolo Pinton
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy.
| |
Collapse
|
332
|
Dong Y, Fernandes C, Liu Y, Wu Y, Wu H, Brophy ML, Deng L, Song K, Wen A, Wong S, Yan D, Towner R, Chen H. Role of endoplasmic reticulum stress signalling in diabetic endothelial dysfunction and atherosclerosis. Diab Vasc Dis Res 2017; 14:14-23. [PMID: 27941052 PMCID: PMC5161113 DOI: 10.1177/1479164116666762] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
It is well established that diabetes mellitus accelerates atherosclerotic vascular disease. Endothelial injury has been proposed to be the initial event in the pathogenesis of atherosclerosis. Endothelium not only acts as a semi-selective barrier but also serves physiological and metabolic functions. Diabetes or high glucose in circulation triggers a series of intracellular responses and organ damage such as endothelial dysfunction and apoptosis. One such response is high glucose-induced chronic endoplasmic reticulum stress in the endothelium. The unfolded protein response is an acute reaction that enables cells to overcome endoplasmic reticulum stress. However, when chronically persistent, endoplasmic reticulum stress response could ultimately lead to endothelial dysfunction and atherosclerosis. Herein, we discuss the scientific advances in understanding endoplasmic reticulum stress-induced endothelial dysfunction, the pathogenesis of diabetes-accelerated atherosclerosis and endoplasmic reticulum stress as a potential target in therapies for diabetic atherosclerosis.
Collapse
Affiliation(s)
- Yunzhou Dong
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Yanjun Liu
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, University of California-Los Angeles School of Medicine, Los Angeles, CA, USA
| | - Yong Wu
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, University of California-Los Angeles School of Medicine, Los Angeles, CA, USA
| | - Hao Wu
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Megan L Brophy
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lin Deng
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Kai Song
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Aiyun Wen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Scott Wong
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daoguang Yan
- Department of Biology, Jinan University, Guangzhou, China
| | - Rheal Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma, OK, USA
| | - Hong Chen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
333
|
Schreiner B, Ankarcrona M. Isolation of Mitochondria-Associated Membranes (MAM) from Mouse Brain Tissue. Methods Mol Biol 2017; 1567:53-68. [PMID: 28276013 DOI: 10.1007/978-1-4939-6824-4_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
During the last decades, increasing evidence indicated that subcellular organelles do not exist as autarkic units but instead communicate constantly and extensively with each other in various ways. Some communication, for example, the exchange of small molecules, requires the marked convergence of two distinct organelles for a certain period of time. The cross talk between endoplasmic reticulum (ER) and mitochondria, two subcellular organelles of utmost importance for cellular bioenergetics and protein homeostasis, has been increasingly investigated under the last years. This development was significantly driven by the establishment of optimized subcellular fractionation techniques. In this chapter, we will describe and critically discuss the currently used protocol for the isolation of the membrane fraction containing mitochondria-associated membranes (MAM).
Collapse
Affiliation(s)
- Bernadette Schreiner
- Center for Alzheimer Research, Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society,, Karolinska Institutet, SE, -141 57, Huddinge, Sweden.
| | - Maria Ankarcrona
- Center for Alzheimer Research, Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society,, Karolinska Institutet, SE, -141 57, Huddinge, Sweden
| |
Collapse
|
334
|
Abstract
The endoplasmic reticulum (ER) is a crucial organelle for coordinating cellular Ca2+ signaling and protein synthesis and folding. Moreover, the dynamic and complex membranous structures constituting the ER allow the formation of contact sites with other organelles and structures, including among others the mitochondria and the plasma membrane (PM). The contact sites that the ER form with mitochondria is a hot topic in research, and the nature of the so-called mitochondria-associated membranes (MAMs) is continuously evolving. The MAMs consist of a proteinaceous tether that physically connects the ER with mitochondria. The MAMs harness the main functions of both organelles to form a specialized subcompartment at the interface of the ER and mitochondria. Under homeostatic conditions, MAMs are crucial for the efficient transfer of Ca2+ from the ER to mitochondria, and for proper mitochondria bioenergetics and lipid synthesis. MAMs are also believed to be the master regulators of mitochondrial shape and motility, and to form a crucial site for autophagosome assembly. Not surprisingly, MAMs have been shown to be a hot spot for the transfer of stress signals from the ER to mitochondria, most notably under the conditions of loss of ER proteostasis, by engaging the unfolded protein response (UPR). In this chapter after an introduction on ER biology and ER stress, we will review the emerging and key signaling roles of the MAMs, which have a root in cellular processes and signaling cascades coordinated by the ER.
Collapse
|
335
|
Over Six Decades of Discovery and Characterization of the Architecture at Mitochondria-Associated Membranes (MAMs). ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 997:13-31. [PMID: 28815519 DOI: 10.1007/978-981-10-4567-7_2] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The discovery of proteins regulating ER-mitochondria tethering including phosphofurin acidic cluster sorting protein 2 (PACS-2) and mitofusin-2 has pushed contact sites between the endoplasmic reticulum (ER) and mitochondria into the spotlight of cell biology. While the field is developing rapidly and controversies have come and gone multiple times during its history, it is sometimes overlooked that significant research has been done decades ago with the original discovery of these structures in the 1950s and the first characterization of their function (and coining of the term mitochondria-associated membrane, MAM) in 1990. Today, an ever-increasing array of proteins localize to the MAM fraction of the endoplasmic reticulum (ER) to regulate the interaction of this organelle with mitochondria. These mitochondria-ER contacts, sometimes referred to as MERCs, regulate a multitude of biological functions, including lipid metabolism, Ca2+ signaling, bioenergetics, inflammation, autophagy, mitochondrial structure, and apoptosis.
Collapse
|
336
|
Role of Endoplasmic Reticulum-Mitochondria Communication in Type 2 Diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 997:171-186. [DOI: 10.1007/978-981-10-4567-7_13] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
337
|
When under pressure, get closer: PERKing up membrane contact sites during ER stress. Biochem Soc Trans 2016; 44:499-504. [PMID: 27068961 DOI: 10.1042/bst20150272] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Indexed: 02/06/2023]
Abstract
The endoplasmic reticulum (ER) is the main hub of cellular Ca(2+)signalling and protein synthesis and folding. The ER moreover is the central player in the formation of contact sites with other organelles and structures, including mitochondria, plasma membrane (PM) and endosomes. The most studied of these, the ER-mitochondria contact sites, are crucial regulators of cellular Ca(2+)homoeostasis, metabolism and cell death signalling. Protein kinase RNA-like ER kinase (PERK), an ER stress kinase and crucial signalling protein in the unfolded protein response (UPR), was found to be able to orchestrate contact sites between the ER and mitochondria and to be indispensable for the pre-apoptotic trafficking of calreticulin (CRT) at the PM during immunogenic cell death (ICD). Furthermore, PERK has recently been linked with ER and PM contact sites through the mechanism of store-operated Ca(2+)entry (SOCE). Here we discuss emerging findings disclosing novel roles of the ER stress sensor PERK in orchestrating inter-organellar communication in the context of ER stress.
Collapse
|
338
|
Role of Mitochondria-Associated Endoplasmic Reticulum Membrane in Inflammation-Mediated Metabolic Diseases. Mediators Inflamm 2016; 2016:1851420. [PMID: 28074080 PMCID: PMC5198184 DOI: 10.1155/2016/1851420] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/17/2016] [Indexed: 12/11/2022] Open
Abstract
Inflammation is considered to be one of the most critical factors involved in the development of complex metabolic diseases such as type 2 diabetes, cancer, and cardiovascular disease. A few decades ago, the discovery of mitochondria-associated endoplasmic reticulum (ER) membrane (MAM) was followed by the identification of its roles in regulating cellular homeostatic processes, ranging from cellular bioenergetics to apoptosis. MAM provides an excellent platform for numerous signaling pathways; among them, inflammatory signaling pathways associated with MAM play a critical role in cellular defense during pathogenic infections and metabolic disorders. However, induction of MAM causes deleterious effects by amplifying mitochondrial reactive oxygen species generation through increased calcium transfer from the ER to mitochondria, thereby causing mitochondrial damage and release of mitochondrial components into the cytosol as damage-associated molecular patterns (DAMPs). These mitochondrial DAMPs rapidly activate MAM-resident inflammasome components and other inflammatory factors, which promote inflammasome complex formation and release of proinflammatory cytokines in pathological conditions. Long-term stimulation of the inflammasome instigates chronic inflammation, leading to the pathogenesis of metabolic diseases. In this review, we summarize the current understanding of MAM and its association with inflammation-mediated metabolic diseases.
Collapse
|
339
|
Abstract
Hepatic steatosis, the first step in the progression of nonalcoholic fatty liver disease, is characterized by triglyceride accumulation in hepatocytes and is highly prevalent in people with obesity. Although initially asymptomatic, hepatic steatosis is an important risk factor for the development of hepatic insulin resistance and type 2 diabetes mellitus and can also progress to more severe pathologies such as nonalcoholic steatohepatitis, liver fibrosis and cirrhosis; hepatic steatosis has, therefore, received considerable research interest in the past 20 years. The lipid accumulation that defines hepatic steatosis disturbs the function of the endoplasmic reticulum (ER) in hepatocytes, thereby generating chronic ER stress that interferes with normal cellular function. Although ubiquitous stress response mechanisms (namely, ER-associated degradation, unfolded protein response and autophagy) are the main processes for restoring cellular proteostasis, these mechanisms are unable to alleviate ER stress in the context of the fatty liver. Furthermore, ER stress and ER stress responses can promote lipid accumulation in hepatocytes in a counter-productive manner and could, therefore, be the origin of a vicious pathological cycle.
Collapse
Affiliation(s)
- Andrei Baiceanu
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
- University of Medicine and Pharmacy Iuliu Hat¸ieganu, Faculty of Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania
| | - Pierre Mesdom
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
| | - Marie Lagouge
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
| | - Fabienne Foufelle
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
| |
Collapse
|
340
|
mTORC1 inhibitor rapamycin and ER stressor tunicamycin induce differential patterns of ER-mitochondria coupling. Sci Rep 2016; 6:36394. [PMID: 27808250 PMCID: PMC5093439 DOI: 10.1038/srep36394] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/14/2016] [Indexed: 01/01/2023] Open
Abstract
Efficient mitochondrial Ca2+ uptake takes place at contact points between the ER and mitochondria, and represents a key regulator of many cell functions. In a previous study with HeLa cells, we showed that ER-to-mitochondria Ca2+ transfer increases during the early phase of ER stress induced by tunicamycin as an adaptive response to stimulate mitochondrial bioenergetics. It remains unknown whether other types of stress signals trigger similar responses. Here we observed that rapamycin, which inhibits the nutrient-sensing complex mTORC1, increased ER-mitochondria coupling in HeLa cells to a similar extent as did tunicamycin. Interestingly, although global responses to both stressors were comparable, there were notable differences in the spatial distribution of such changes. While tunicamycin increased organelle proximity primarily in the perinuclear region, rapamycin increased organelle contacts throughout the entire cell. These differences were paralleled by dissimilar alterations in the distribution of regulatory proteins of the ER-mitochondria interface, heterogeneities in mitochondrial Ca2+ uptake, and the formation of domains within the mitochondrial network with varying mitochondrial transmembrane potential. Collectively, these data suggest that while increasing ER-mitochondria coupling appears to represent a general response to cell stress, the intracellular distribution of the associated responses needs to be tailored to meet specific cellular requirements.
Collapse
|
341
|
Requejo-Aguilar R, Bolaños JP. Mitochondrial control of cell bioenergetics in Parkinson's disease. Free Radic Biol Med 2016; 100:123-137. [PMID: 27091692 PMCID: PMC5065935 DOI: 10.1016/j.freeradbiomed.2016.04.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/13/2016] [Accepted: 04/14/2016] [Indexed: 12/15/2022]
Abstract
Parkinson disease (PD) is a neurodegenerative disorder characterized by a selective loss of dopaminergic neurons in the substantia nigra. The earliest biochemical signs of the disease involve failure in mitochondrial-endoplasmic reticulum cross talk and lysosomal function, mitochondrial electron chain impairment, mitochondrial dynamics alterations, and calcium and iron homeostasis abnormalities. These changes are associated with increased mitochondrial reactive oxygen species (mROS) and energy deficiency. Recently, it has been reported that, as an attempt to compensate for the mitochondrial dysfunction, neurons invoke glycolysis as a low-efficient mode of energy production in models of PD. Here, we review how mitochondria orchestrate the maintenance of cellular energetic status in PD, with special focus on the switch from oxidative phosphorylation to glycolysis, as well as the implication of endoplasmic reticulum and lysosomes in the control of bioenergetics.
Collapse
Affiliation(s)
- Raquel Requejo-Aguilar
- Department of Biochemistry and Molecular Biology, University of Cordoba, Institute Maimonides of Biomedical Investigation of Cordoba (IMIBIC), Cordoba, Spain
| | - Juan P Bolaños
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Zacarias Gonzalez, 2, 37007 Salamanca, Spain.
| |
Collapse
|
342
|
Rodríguez-Arribas M, Yakhine-Diop SMS, Pedro JMBS, Gómez-Suaga P, Gómez-Sánchez R, Martínez-Chacón G, Fuentes JM, González-Polo RA, Niso-Santano M. Mitochondria-Associated Membranes (MAMs): Overview and Its Role in Parkinson's Disease. Mol Neurobiol 2016; 54:6287-6303. [PMID: 27714635 DOI: 10.1007/s12035-016-0140-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 09/19/2016] [Indexed: 12/21/2022]
Abstract
Mitochondria-associated membranes (MAMs) are structures that regulate physiological functions between endoplasmic reticulum (ER) and mitochondria in order to maintain calcium signaling and mitochondrial biogenesis. Several proteins located in MAMs, including those encoded by PARK genes and some of neurodegeneration-related proteins (huntingtin, presenilin, etc.), ensure this regulation. In this regard, MAM alteration is associated with neurodegenerative diseases such as Parkinson's (PD), Alzheimer's (AD), and Huntington's diseases (HD) and contributes to the appearance of the pathogenesis features, i.e., autophagy dysregulation, mitochondrial dysfunction, oxidative stress, and lately, neuronal death. Moreover,, ER stress and/or damaged mitochondria can be the cause of these disruptions. Therefore, ER-mitochondria contact structure and function are crucial to multiple cellular processes. This review is focused on the molecular interaction between ER and mitochondria indispensable to MAM formation and on MAM alteration-induced etiology of neurodegenerative diseases.
Collapse
Affiliation(s)
- M Rodríguez-Arribas
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain.,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain
| | - S M S Yakhine-Diop
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain.,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain
| | - J M Bravo-San Pedro
- Equipe 11 labellisée Ligue contre le Cancer, Centre de Recherche des Cordeliers, 75006, Paris, France.,INSERM U1138, 75006, Paris, France.,Université Paris Descartes/Paris V, Sorbonne Paris Cité, 75006, Paris, France.,Université Pierre et Marie Curie/Paris VI, 75006, Paris, France.,Gustave Roussy Comprehensive Cancer Institute, 94805, Villejuif, France
| | - P Gómez-Suaga
- Department Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute Kings College London, London, SE5 9RX, UK
| | - R Gómez-Sánchez
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - G Martínez-Chacón
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain.,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain
| | - J M Fuentes
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain.,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain
| | - R A González-Polo
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain. .,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain.
| | - M Niso-Santano
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Universidad de Extremadura, Avda. De la Universidad S/N, C.P, 10003, Cáceres, Cáceres, Spain. .,Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Avda. de la Universidad s/n, C.P, 10003, Cáceres, Cáceres, Spain.
| |
Collapse
|
343
|
Pagliassotti MJ, Kim PY, Estrada AL, Stewart CM, Gentile CL. Endoplasmic reticulum stress in obesity and obesity-related disorders: An expanded view. Metabolism 2016; 65:1238-46. [PMID: 27506731 PMCID: PMC4980576 DOI: 10.1016/j.metabol.2016.05.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 04/01/2016] [Accepted: 05/06/2016] [Indexed: 02/07/2023]
Abstract
The endoplasmic reticulum (ER) is most notable for its central roles in calcium ion storage, lipid biosynthesis, and protein sorting and processing. By virtue of its extensive membrane contact sites that connect the ER to most other organelles and to the plasma membrane, the ER can also regulate diverse cellular processes including inflammatory and insulin signaling, nutrient metabolism, and cell proliferation and death via a signaling pathway called the unfolded protein response (UPR). Chronic UPR activation has been observed in liver and/or adipose tissue of dietary and genetic murine models of obesity, and in human obesity and non-alcoholic fatty liver disease (NAFLD). Activation of the UPR in obesity and obesity-related disorders likely has two origins. One linked to classic ER stress involving the ER lumen and one linked to alterations to the ER membrane environment. This review discusses both of these origins and also considers the role of post-translational protein modifications, such as acetylation and palmitoylation, and ER-mitochondrial interactions to obesity-mediated impairments in the ER and activation of the UPR.
Collapse
Affiliation(s)
| | - Paul Y Kim
- Department of Biological Sciences, Grambling State University
| | - Andrea L Estrada
- Department of Food Science and Human Nutrition, Colorado State University
| | - Claire M Stewart
- Department of Food Science and Human Nutrition, Colorado State University
| | | |
Collapse
|
344
|
Elustondo P, Martin LA, Karten B. Mitochondrial cholesterol import. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:90-101. [PMID: 27565112 DOI: 10.1016/j.bbalip.2016.08.012] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/15/2016] [Accepted: 08/19/2016] [Indexed: 02/06/2023]
Abstract
All animal subcellular membranes require cholesterol, which influences membrane fluidity and permeability, fission and fusion processes, and membrane protein function. The distribution of cholesterol among subcellular membranes is highly heterogeneous and the cholesterol content of each membrane must be carefully regulated. Compared to other subcellular membranes, mitochondrial membranes are cholesterol-poor, particularly the inner mitochondrial membrane (IMM). As a result, steroidogenesis can be controlled through the delivery of cholesterol to the IMM, where it is converted to pregnenolone. The low basal levels of cholesterol also make mitochondria sensitive to changes in cholesterol content, which can have a relatively large impact on the biophysical and functional characteristics of mitochondrial membranes. Increased mitochondrial cholesterol levels have been observed in diverse pathological conditions including cancer, steatohepatitis, Alzheimer disease and Niemann-Pick Type C1-deficiency, and are associated with increased oxidative stress, impaired oxidative phosphorylation, and changes in the susceptibility to apoptosis, among other alterations in mitochondrial function. Mitochondria are not included in the vesicular trafficking network; therefore, cholesterol transport to mitochondria is mostly achieved through the activity of lipid transfer proteins at membrane contact sites or by cytosolic, diffusible lipid transfer proteins. Here we will give an overview of the main mechanisms involved in mitochondrial cholesterol import, focusing on the steroidogenic acute regulatory protein StAR/STARD1 and other members of the StAR-related lipid transfer (START) domain protein family, and we will discuss how changes in mitochondrial cholesterol levels can arise and affect mitochondrial function. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum.
Collapse
Affiliation(s)
- Pia Elustondo
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Laura A Martin
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Barbara Karten
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| |
Collapse
|
345
|
Raturi A, Gutiérrez T, Ortiz-Sandoval C, Ruangkittisakul A, Herrera-Cruz MS, Rockley JP, Gesson K, Ourdev D, Lou PH, Lucchinetti E, Tahbaz N, Zaugg M, Baksh S, Ballanyi K, Simmen T. TMX1 determines cancer cell metabolism as a thiol-based modulator of ER-mitochondria Ca2+ flux. J Cell Biol 2016; 214:433-44. [PMID: 27502484 PMCID: PMC4987292 DOI: 10.1083/jcb.201512077] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 07/15/2016] [Indexed: 12/31/2022] Open
Abstract
Cancer cells are critically dependent on ER–mitochondria Ca2+ flux that regulates their bioenergetics. Here, Raturi et al. identify the ER oxidoreductase TMX1 as a thiol-dependent regulator of this intracellular signaling mechanism within cancer cells. The flux of Ca2+ from the endoplasmic reticulum (ER) to mitochondria regulates mitochondria metabolism. Within tumor tissue, mitochondria metabolism is frequently repressed, leading to chemotherapy resistance and increased growth of the tumor mass. Therefore, altered ER–mitochondria Ca2+ flux could be a cancer hallmark, but only a few regulatory proteins of this mechanism are currently known. One candidate is the redox-sensitive oxidoreductase TMX1 that is enriched on the mitochondria-associated membrane (MAM), the site of ER–mitochondria Ca2+ flux. Our findings demonstrate that cancer cells with low TMX1 exhibit increased ER Ca2+, accelerated cytosolic Ca2+ clearance, and reduced Ca2+ transfer to mitochondria. Thus, low levels of TMX1 reduce ER–mitochondria contacts, shift bioenergetics away from mitochondria, and accelerate tumor growth. For its role in intracellular ER–mitochondria Ca2+ flux, TMX1 requires its thioredoxin motif and palmitoylation to target to the MAM. As a thiol-based tumor suppressor, TMX1 increases mitochondrial ATP production and apoptosis progression.
Collapse
Affiliation(s)
- Arun Raturi
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Tomás Gutiérrez
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Carolina Ortiz-Sandoval
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Araya Ruangkittisakul
- Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Maria Sol Herrera-Cruz
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Jeremy P Rockley
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Kevin Gesson
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Dimitar Ourdev
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Phing-How Lou
- Department of Anesthesiology and Pain Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Eliana Lucchinetti
- Department of Anesthesiology and Pain Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Nasser Tahbaz
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Michael Zaugg
- Department of Anesthesiology and Pain Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Shairaz Baksh
- Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada Department of Biochemistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada Department of Oncology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada Alberta Inflammatory Bowel Disease Consortium, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Klaus Ballanyi
- Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| | - Thomas Simmen
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G2H7, Canada
| |
Collapse
|
346
|
André F, Corazao-Rozas P, Idziorek T, Quesnel B, Kluza J, Marchetti P. GILZ overexpression attenuates endoplasmic reticulum stress-mediated cell death via the activation of mitochondrial oxidative phosphorylation. Biochem Biophys Res Commun 2016; 478:513-20. [PMID: 27416758 DOI: 10.1016/j.bbrc.2016.07.053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 07/09/2016] [Indexed: 12/14/2022]
Abstract
The Glucocorticoïd-induced leucine zipper (GILZ) protein has profound anti-inflammatory activities in haematopoietic cells. GILZ regulates numerous signal transduction pathways involved in proliferation and survival of normal and neoplastic cells. Here, we have demonstrated the potential of GILZ in alleviating apoptosis induced by ER stress inducers. Whereas the glucocorticoid, dexamethasone, protects from tunicamycin-induced cell death, silencing endogeneous GILZ in dexamethasone-treated cancer cells alter the capacity of glucocorticoids to protect from tunicamycin-mediated apoptosis. Under ER stress conditions, overexpression of GILZ significantly reduced activation of mitochondrial pathway of apoptosis by maintaining Bcl-xl level. GILZ protein affects the UPR signaling shifting the balance towards pro-survival signals as judged by down-regulation of CHOP, ATF4, XBP1s mRNA and increase in GRP78 protein level. Interestingly, GILZ sustains high mitochondrial OXPHOS during ER stress and cytoprotection mediated by GILZ is abolished in cells depleted of mitochondrial DNA, which are OXPHOS-deficient. These findings reveal a new role of GILZ, which acts as a cytoprotector against ER stress through a pathway involving mitochondrial OXPHOS.
Collapse
Affiliation(s)
- Fanny André
- INSERM UMR-S 1172, Université de Lille, 1 Place Verdun F-59045 Cedex, France
| | - Paola Corazao-Rozas
- CHU Lille, Banque de Tissus & Biologie Cellulaire -Thérapie Cellulaire, F-59000 Lille France
| | - Thierry Idziorek
- INSERM UMR-S 1172, Université de Lille, 1 Place Verdun F-59045 Cedex, France
| | - Bruno Quesnel
- INSERM UMR-S 1172, Université de Lille, 1 Place Verdun F-59045 Cedex, France
| | - Jérome Kluza
- INSERM UMR-S 1172, Université de Lille, 1 Place Verdun F-59045 Cedex, France
| | - Philippe Marchetti
- INSERM UMR-S 1172, Université de Lille, 1 Place Verdun F-59045 Cedex, France; CHU Lille, Banque de Tissus & Biologie Cellulaire -Thérapie Cellulaire, F-59000 Lille France.
| |
Collapse
|
347
|
Giacomello M, Pellegrini L. The coming of age of the mitochondria-ER contact: a matter of thickness. Cell Death Differ 2016; 23:1417-27. [PMID: 27341186 DOI: 10.1038/cdd.2016.52] [Citation(s) in RCA: 338] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 05/02/2016] [Accepted: 05/05/2016] [Indexed: 12/12/2022] Open
Abstract
The sites of near-contact between the mitochondrion and the endoplasmic reticulum (ER) have earned a lot of attention due to their key role in the maintenance of lipid and calcium (Ca(2+)) homeostasis, in the initiation of autophagy and mitochondrial division, and in sensing metabolic shifts. At these sites, typically called MAMs (mitochondria-associated ER membranes) or MERCs (mitochondria-ER contacts), the organelles juxtapose at a distance that can range from ~10 to ~50 nm. The multifunctional role of this subcellular compartment is puzzling; further, recent studies have shown that mitochondria-ER contacts are highly plastic structures that remodel upon metabolic transitions and that their activity in controlling lipid homeostasis could be involved in Alzheimer's disease pathogenesis. This review aims at integrating the functions of this subcellular compartment to its most characterizing and unexplored structural parameter, their 'thickness': that is, the width of the cleft that separates the cytosolic face of the outer mitochondrial membrane from that of the ER. We describe and discuss the reasons why the thickness of a MERC should be considered a regulated structural parameter of the cell that defines and controls its function. Further, we propose a MERC classification that will help organize the expanding field of MERCs biology and of their role in cell physiology and human disease.
Collapse
Affiliation(s)
- M Giacomello
- Department of Biology, Università di Padova, Padua, Italy.,Venetian Institute of Molecular Medicine, Padua, Italy
| | - L Pellegrini
- Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Universitè Laval, Quebec, Québec, Canada.,Mitochondria Biology Laboratory, CRIUSMQ, Quebec, Québec, Canada
| |
Collapse
|
348
|
Patra M, Mahata SK, Padhan DK, Sen M. CCN6 regulates mitochondrial function. J Cell Sci 2016; 129:2841-51. [PMID: 27252383 DOI: 10.1242/jcs.186247] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 04/08/2016] [Indexed: 12/29/2022] Open
Abstract
Despite established links of CCN6, or Wnt induced signaling protein-3 (WISP3), with progressive pseudo rheumatoid dysplasia, functional characterization of CCN6 remains incomplete. In light of the documented negative correlation between accumulation of reactive oxygen species (ROS) and CCN6 expression, we investigated whether CCN6 regulates ROS accumulation through its influence on mitochondrial function. We found that CCN6 localizes to mitochondria, and depletion of CCN6 in the chondrocyte cell line C-28/I2 by using siRNA results in altered mitochondrial electron transport and respiration. Enhanced electron transport chain (ETC) activity of CCN6-depleted cells was reflected by increased mitochondrial ROS levels in association with augmented mitochondrial ATP synthesis, mitochondrial membrane potential and Ca(2+) Additionally, CCN6-depleted cells display ROS-dependent PGC1α (also known as PPARGC1A) induction, which correlates with increased mitochondrial mass and volume density, together with altered mitochondrial morphology. Interestingly, transcription factor Nrf2 (also known as NFE2L2) repressed CCN6 expression. Taken together, our results suggest that CCN6 acts as a molecular brake, which is appropriately balanced by Nrf2, in regulating mitochondrial function.
Collapse
Affiliation(s)
- Milan Patra
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian institute of Chemical Biology, 4-Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Sushil K Mahata
- Metabolic Physiology and Ultrastructure Biology Laboratory, University of California, San Diego, CA 92093-0732, USA Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
| | - Deepesh K Padhan
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian institute of Chemical Biology, 4-Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Malini Sen
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian institute of Chemical Biology, 4-Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| |
Collapse
|
349
|
Williams A, Hayashi T, Wolozny D, Yin B, Su TC, Betenbaugh MJ, Su TP. The non-apoptotic action of Bcl-xL: regulating Ca(2+) signaling and bioenergetics at the ER-mitochondrion interface. J Bioenerg Biomembr 2016; 48:211-25. [PMID: 27155879 PMCID: PMC6737942 DOI: 10.1007/s10863-016-9664-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/26/2016] [Indexed: 12/20/2022]
Abstract
Bcl-2 family proteins are known to competitively regulate Ca(2+); however, the specific inter-organelle signaling pathways and related cellular functions are not fully elucidated. In this study, a portion of Bcl-xL was detected at the ER-mitochondrion interface or MAM (mitochondria-associated ER membrane) in association with type 3 inositol 1,4,5-trisphosphate receptors (IP3R3); an association facilitated by the BH4 and transmembrane domains of Bcl-xL. Moreover, increasing Bcl-xL expression enhanced transient mitochondrial Ca(2+) levels upon ER Ca(2+) depletion induced by short-term, non-apoptotic incubation with thapsigargin (Tg), while concomitantly reducing cytosolic Ca(2+) release. These mitochondrial changes appear to be IP3R3-dependent and resulted in decreased NAD/NADH ratios and higher electron transport chain oxidase activity. Interestingly, extended Tg exposure stimulated ER stress, but not apoptosis, and further enhanced TCA cycling. Indeed, confocal analysis indicated that Bcl-xL translocated to the MAM and increased its interaction with IP3R3 following extended Tg treatment. Thus, the MAM is a critical cell-signaling junction whereby Bcl-xL dynamically interacts with IP3R3 to coordinate mitochondrial Ca(2+) transfer and alters cellular metabolism in order to increase the cells' bioenergetic capacity, particularly during periods of stress.
Collapse
Affiliation(s)
- Abasha Williams
- Cellular Pathobiology Section, IRP, NIDA, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
- Division of Biotechnology Review and Research II, FDA/CDER/OPS/OBP, 10903 New Hampshire Ave, Silver Spring, MD, 20993, USA
| | - Teruo Hayashi
- Cellular Pathobiology Section, IRP, NIDA, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
- Seiwakai Nishikawa Hospital, 293-2 Minato-Machi, Hamada, Shimane, 697-0052, Japan
| | - Daniel Wolozny
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
| | - Bojiao Yin
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
| | - Tzu-Chieh Su
- Cellular Pathobiology Section, IRP, NIDA, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Michael J Betenbaugh
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA.
| | - Tsung-Ping Su
- Cellular Pathobiology Section, IRP, NIDA, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA.
| |
Collapse
|
350
|
Filadi R, Greotti E, Turacchio G, Luini A, Pozzan T, Pizzo P. Presenilin 2 Modulates Endoplasmic Reticulum-Mitochondria Coupling by Tuning the Antagonistic Effect of Mitofusin 2. Cell Rep 2016; 15:2226-2238. [PMID: 27239030 DOI: 10.1016/j.celrep.2016.05.013] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/23/2016] [Accepted: 04/28/2016] [Indexed: 01/31/2023] Open
Abstract
Communication between organelles plays key roles in cell biology. In particular, physical and functional coupling of the endoplasmic reticulum (ER) and mitochondria is crucial for regulation of various physiological and pathophysiological processes. Here, we demonstrate that Presenilin 2 (PS2), mutations in which underlie familial Alzheimer's disease (FAD), promotes ER-mitochondria coupling only in the presence of mitofusin 2 (Mfn2). PS2 is not necessary for the antagonistic effect of Mfn2 on organelle coupling, although its abundance can tune it. The two proteins physically interact, whereas their homologues Mfn1 and PS1 are dispensable for this interplay. Moreover, PS2 mutants associated with FAD are more effective than the wild-type form in modulating ER-mitochondria tethering because their binding to Mfn2 in mitochondria-associated membranes is favored. We propose a revised model for ER-mitochondria interaction to account for these findings and discuss possible implications for FAD pathogenesis.
Collapse
Affiliation(s)
- Riccardo Filadi
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/B, Padua 35131, Italy
| | - Elisa Greotti
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/B, Padua 35131, Italy; Department of Biomedical Sciences, Institute of Neuroscience, Italian National Research Council (CNR), via U. Bassi 58/B, Padua 35131, Italy
| | - Gabriele Turacchio
- Department of Biomedical Sciences, Institute of Protein Biochemistry, Italian National Research Council (CNR), via P. Castellino 111, Naples 80131, Italy
| | - Alberto Luini
- Department of Biomedical Sciences, Institute of Protein Biochemistry, Italian National Research Council (CNR), via P. Castellino 111, Naples 80131, Italy
| | - Tullio Pozzan
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/B, Padua 35131, Italy; Venetian Institute of Molecular Medicine, via Orus 2, Padua 35131, Italy; Department of Biomedical Sciences, Institute of Neuroscience, Italian National Research Council (CNR), via U. Bassi 58/B, Padua 35131, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/B, Padua 35131, Italy.
| |
Collapse
|