151
|
Chen Z, Cordero J, Alqarni AM, Slack C, Zeidler MP, Bellantuono I. Zoledronate extends healthspan and survival via the mevalonate pathway in a FOXO-dependent manner. J Gerontol A Biol Sci Med Sci 2021; 77:1494-1502. [PMID: 34137822 PMCID: PMC9373971 DOI: 10.1093/gerona/glab172] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Indexed: 12/21/2022] Open
Abstract
Over recent decades, increased longevity has not been paralleled by extended healthspan, resulting in more years spent with multiple diseases in older age. As such, interventions to improve healthspan are urgently required. Zoledronate is a nitrogen containing bisphosphonate, which inhibits the farnesyl pyrophosphate synthase (FPPS) enzyme, central to the mevalonate pathway. It is already used clinically to prevent fractures in osteoporotic patients, who have been reported to derive unexpected and unexplained survival benefits. Using Drosophila as a model we determined the effects of Zoledronate on lifespan, parameters of healthspan (climbing ability and intestinal dysplasia) and the ability to confer resistance to oxidative stress using a combination of genetically manipulated Drosophila strains and Western blotting. Our study shows that Zoledronate extended lifespan, improved climbing activity and reduced intestinal epithelial dysplasia and permeability with age. Mechanistic studies showed that Zoledronate conferred resistance to oxidative stress and reduced accumulation of X-ray-induced DNA damage via inhibition of FPPS. Moreover, Zoledronate was associated with inhibition of pAKT in the mTOR pathway downstream of the mevalonate pathway and required dFOXO for its action, both molecules associated with increased longevity. Taken together, our work indicates that Zoledronate, a drug already widely used to prevent osteoporosis and dosed only once a year, modulates important mechanisms of ageing. Its repurposing holds great promise as a treatment to improve healthspan.
Collapse
Affiliation(s)
- Zhengqi Chen
- Healthy Lifespan Institute, Department of Oncology and Metabolism, The Medical School, University of Sheffield, Sheffield
| | - Julia Cordero
- Institute of Cancer Sciences, University of Glasgow, Beatson Institute for Cancer, Bearsden, Glasgow
| | - Adel M Alqarni
- Department of Biomedical Science, The University of Sheffield, Western Bank, Sheffield
| | - Cathy Slack
- School of Life & Health Sciences, Aston University, Aston Triangle, Birmingham
| | - Martin P Zeidler
- Department of Biomedical Science, The University of Sheffield, Western Bank, Sheffield
| | - Ilaria Bellantuono
- Healthy Lifespan Institute, Department of Oncology and Metabolism, The Medical School, University of Sheffield, Sheffield
| |
Collapse
|
152
|
Zhou Y, Guo J, Wang X, Cheng Y, Guan J, Barman P, Sun MA, Fu Y, Wei W, Feng C, Lilly MA, Wei Y. FKBP39 controls nutrient dependent Nprl3 expression and TORC1 activity in Drosophila. Cell Death Dis 2021; 12:571. [PMID: 34078879 PMCID: PMC8172852 DOI: 10.1038/s41419-021-03860-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 05/20/2021] [Accepted: 05/21/2021] [Indexed: 01/07/2023]
Abstract
Target of Rapamycin Complex 1 (TORC1) is a master regulator that coordinates nutrient status with cell metabolism. The GTPase-activating protein towards Rags complex 1 (GATOR1) inhibits TORC1 activity and protects cells from damage during periods of stress. Here we characterize multiple pathways that regulate the expression of the GATOR1 component Nprl3 in Drosophila. We determine that the stability of Nprl3 is impacted by the Unassembled Soluble Complex Proteins Degradation (USPD) pathway. In addition, we find that FK506 binding protein 39 (FKBP39)-dependent proteolytic destruction maintains Nprl3 at low levels in nutrient replete conditions. Nutrient starvation abrogates the degradation of the Nprl3 protein and rapidly promotes Nprl3 accumulation. Consistent with a role in promoting the stability of a TORC1 inhibitor, mutations in fkbp39 decrease TORC1 activity and increase autophagy. Finally, we show that the 5′UTR of nprl3 transcripts contain a functional upstream open reading frame (uORF) that inhibits main ORF translation. In summary, our work has uncovered novel mechanisms of Nprl3 regulation and identifies an important role for FKBP39 in the control of cellular metabolism.
Collapse
Affiliation(s)
- Ying Zhou
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Jian Guo
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Xinyu Wang
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Yang Cheng
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Jianwen Guan
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Priyam Barman
- Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Ming-An Sun
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
| | - Yuanyuan Fu
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Wanhong Wei
- Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Congjing Feng
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, China
| | - Mary A Lilly
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Youheng Wei
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China. .,Animal Physiology Group, College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China.
| |
Collapse
|
153
|
Heier C, Klishch S, Stilbytska O, Semaniuk U, Lushchak O. The Drosophila model to interrogate triacylglycerol biology. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158924. [PMID: 33716135 DOI: 10.1016/j.bbalip.2021.158924] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/24/2021] [Accepted: 03/05/2021] [Indexed: 12/21/2022]
Abstract
The deposition of storage fat in the form of triacylglycerol (TAG) is an evolutionarily conserved strategy to cope with fluctuations in energy availability and metabolic stress. Organismal TAG storage in specialized adipose tissues provides animals a metabolic reserve that sustains survival during development and starvation. On the other hand, excessive accumulation of adipose TAG, defined as obesity, is associated with an increasing prevalence of human metabolic diseases. During the past decade, the fruit fly Drosophila melanogaster, traditionally used in genetics and developmental biology, has been established as a versatile model system to study TAG metabolism and the etiology of lipid-associated metabolic diseases. Similar to humans, Drosophila TAG homeostasis relies on the interplay of organ systems specialized in lipid uptake, synthesis, and processing, which are integrated by an endocrine network of hormones and messenger molecules. Enzymatic formation of TAG from sugar or dietary lipid, its storage in lipid droplets, and its mobilization by lipolysis occur via mechanisms largely conserved between Drosophila and humans. Notably, dysfunctional Drosophila TAG homeostasis occurs in the context of aging, overnutrition, or defective gene function, and entails tissue-specific and organismal pathologies that resemble human disease. In this review, we summarize the physiology and biochemistry of TAG in Drosophila and outline the potential of this organism as a model system to understand the genetic and dietary basis of TAG storage and TAG-related metabolic disorders.
Collapse
Affiliation(s)
- Christoph Heier
- Institute of Molecular Biosciences, University of Graz, NAWI Graz, Humboldtstrasse 50, A-8010 Graz, Austria; BioTechMed-Graz, Graz, Austria.
| | - Svitlana Klishch
- Department of Biochemistry and Biotechnology, Department Biochemistry 1, Faculty of Natural Sciences, Vasyl Stefanyk Precarpathian National University, 57 Shevchenka str, Ivano-Frankivsk 76018, Ukraine
| | - Olha Stilbytska
- Department of Biochemistry and Biotechnology, Department Biochemistry 1, Faculty of Natural Sciences, Vasyl Stefanyk Precarpathian National University, 57 Shevchenka str, Ivano-Frankivsk 76018, Ukraine
| | - Uliana Semaniuk
- Department of Biochemistry and Biotechnology, Department Biochemistry 1, Faculty of Natural Sciences, Vasyl Stefanyk Precarpathian National University, 57 Shevchenka str, Ivano-Frankivsk 76018, Ukraine
| | - Oleh Lushchak
- Department of Biochemistry and Biotechnology, Department Biochemistry 1, Faculty of Natural Sciences, Vasyl Stefanyk Precarpathian National University, 57 Shevchenka str, Ivano-Frankivsk 76018, Ukraine.
| |
Collapse
|
154
|
Genotype and Trait Specific Responses to Rapamycin Intake in Drosophila melanogaster. INSECTS 2021; 12:insects12050474. [PMID: 34065203 PMCID: PMC8161023 DOI: 10.3390/insects12050474] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 12/11/2022]
Abstract
Simple Summary Rapamycin is commonly used as an immunosuppressant, but also as an anti-aging medicine. Despite its widespread use, results suggest that there is large variability in drug efficiency among patients, and limited knowledge exists about potential side-effects. In the present study, we investigated the effects of rapamycin using the common fruit fly as model organism. Six genetically distinct lines were exposed to rapamycin, and the phenotypic consequence on fecundity, longevity and heat stress tolerance was quantified. Flies exposed to rapamycin had increased longevity and heat stress tolerance, however a side effect in the form of decreased fecundity was also observed. Our data clearly show that the costs and benefits of rapamycin treatment is strongly genotype dependent. These observations are important as they imply that a ‘one size fits all’ approach when it comes to rapamycin treatment is not advisable. Future studies should address the underlying genetic component that drive the drug response variability. Abstract Rapamycin is a powerful inhibitor of the TOR (Target of Rapamycin) pathway, which is an evolutionarily conserved protein kinase, that plays a central role in plants and animals. Rapamycin is used globally as an immunosuppressant and as an anti-aging medicine. Despite widespread use, treatment efficiency varies considerably across patients, and little is known about potential side effects. Here we seek to investigate the effects of rapamycin by using Drosophila melanogaster as model system. Six isogenic D. melanogaster lines were assessed for their fecundity, male longevity and male heat stress tolerance with or without rapamycin treatment. The results showed increased longevity and heat stress tolerance for male flies treated with rapamycin. Conversely, the fecundity of rapamycin-exposed individuals was lower than for flies from the non-treated group, suggesting unwanted side effects of the drug in D. melanogaster. We found strong evidence for genotype-by-treatment interactions suggesting that a ‘one size fits all’ approach when it comes to treatment with rapamycin is not recommendable. The beneficial responses to rapamycin exposure for stress tolerance and longevity are in agreement with previous findings, however, the unexpected effects on reproduction are worrying and need further investigation and question common believes that rapamycin constitutes a harmless drug.
Collapse
|
155
|
Holtze S, Gorshkova E, Braude S, Cellerino A, Dammann P, Hildebrandt TB, Hoeflich A, Hoffmann S, Koch P, Terzibasi Tozzini E, Skulachev M, Skulachev VP, Sahm A. Alternative Animal Models of Aging Research. Front Mol Biosci 2021; 8:660959. [PMID: 34079817 PMCID: PMC8166319 DOI: 10.3389/fmolb.2021.660959] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/08/2021] [Indexed: 12/23/2022] Open
Abstract
Most research on mechanisms of aging is being conducted in a very limited number of classical model species, i.e., laboratory mouse (Mus musculus), rat (Rattus norvegicus domestica), the common fruit fly (Drosophila melanogaster) and roundworm (Caenorhabditis elegans). The obvious advantages of using these models are access to resources such as strains with known genetic properties, high-quality genomic and transcriptomic sequencing data, versatile experimental manipulation capabilities including well-established genome editing tools, as well as extensive experience in husbandry. However, this approach may introduce interpretation biases due to the specific characteristics of the investigated species, which may lead to inappropriate, or even false, generalization. For example, it is still unclear to what extent knowledge of aging mechanisms gained in short-lived model organisms is transferable to long-lived species such as humans. In addition, other specific adaptations favoring a long and healthy life from the immense evolutionary toolbox may be entirely missed. In this review, we summarize the specific characteristics of emerging animal models that have attracted the attention of gerontologists, we provide an overview of the available data and resources related to these models, and we summarize important insights gained from them in recent years. The models presented include short-lived ones such as killifish (Nothobranchius furzeri), long-lived ones such as primates (Callithrix jacchus, Cebus imitator, Macaca mulatta), bathyergid mole-rats (Heterocephalus glaber, Fukomys spp.), bats (Myotis spp.), birds, olms (Proteus anguinus), turtles, greenland sharks, bivalves (Arctica islandica), and potentially non-aging ones such as Hydra and Planaria.
Collapse
Affiliation(s)
- Susanne Holtze
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Ekaterina Gorshkova
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Stan Braude
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
| | - Alessandro Cellerino
- Biology Laboratory, Scuola Normale Superiore, Pisa, Italy
- Leibniz Institute on Aging – Fritz Lipmann Institute, Jena, Germany
| | - Philip Dammann
- Department of General Zoology, Faculty of Biology, University of Duisburg-Essen, Essen, Germany
- Central Animal Laboratory, University Hospital Essen, Essen, Germany
| | - Thomas B. Hildebrandt
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
- Faculty of Veterinary Medicine, Free University of Berlin, Berlin, Germany
| | - Andreas Hoeflich
- Division Signal Transduction, Institute for Genome Biology, Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany
| | - Steve Hoffmann
- Computational Biology Group, Leibniz Institute on Aging – Fritz Lipmann Institute, Jena, Germany
| | - Philipp Koch
- Core Facility Life Science Computing, Leibniz Institute on Aging – Fritz Lipmann Institute, Jena, Germany
| | - Eva Terzibasi Tozzini
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Maxim Skulachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Vladimir P. Skulachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Arne Sahm
- Computational Biology Group, Leibniz Institute on Aging – Fritz Lipmann Institute, Jena, Germany
| |
Collapse
|
156
|
Packer M. Longevity genes, cardiac ageing, and the pathogenesis of cardiomyopathy: implications for understanding the effects of current and future treatments for heart failure. Eur Heart J 2021; 41:3856-3861. [PMID: 32460327 PMCID: PMC7599035 DOI: 10.1093/eurheartj/ehaa360] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 03/26/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022] Open
Abstract
The two primary molecular regulators of lifespan are sirtuin-1 (SIRT1) and mammalian target of rapamycin complex 1 (mTORC1). Each plays a central role in two highly interconnected pathways that modulate the balance between cellular growth and survival. The activation of SIRT1 [along with peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α) and adenosine monophosphate-activated protein kinase (AMPK)] and the suppression of mTORC1 (along with its upstream regulator, Akt) act to prolong organismal longevity and retard cardiac ageing. Both activation of SIRT1/PGC-1α and inhibition of mTORC1 shifts the balance of cellular priorities so as to promote cardiomyocyte survival over growth, leading to cardioprotective effects in experimental models. These benefits may be related to direct actions to modulate oxidative stress, organellar function, proinflammatory pathways, and maladaptive hypertrophy. In addition, a primary shared benefit of both SIRT1/PGC-1α/AMPK activation and Akt/mTORC1 inhibition is the enhancement of autophagy, a lysosome-dependent degradative pathway, which clears the cytosol of dysfunctional organelles and misfolded proteins that drive the ageing process by increasing oxidative and endoplasmic reticulum stress. Autophagy underlies the ability of SIRT1/PGC-1α/AMPK activation and Akt/mTORC1 suppression to extend lifespan, mitigate cardiac ageing, alleviate cellular stress, and ameliorate the development and progression of cardiomyopathy; silencing of autophagy genes abolishes these benefits. Loss of SIRT1/PGC-1α/AMPK function or hyperactivation of Akt/mTORC1 is a consistent feature of experimental cardiomyopathy, and reversal of these abnormalities mitigates the development of heart failure. Interestingly, most treatments that have been shown to be clinically effective in the treatment of chronic heart failure with a reduced ejection fraction have been reported experimentally to exert favourable effects to activate SIRT1/PGC-1α/AMPK and/or suppress Akt/mTORC1, and thereby, to promote autophagic flux. Therefore, the impairment of autophagy resulting from derangements in longevity gene signalling is likely to represent a seminal event in the evolution and progression of cardiomyopathy. ![]()
Collapse
Affiliation(s)
- Milton Packer
- Baylor Heart and Vascular Institute, Baylor University Medical Center, 621 N. Hall Street, Dallas, TX 75226, USA.,Imperial College, London, UK
| |
Collapse
|
157
|
Lu YX, Regan JC, Eßer J, Drews LF, Weinseis T, Stinn J, Hahn O, Miller RA, Grönke S, Partridge L. A TORC1-histone axis regulates chromatin organisation and non-canonical induction of autophagy to ameliorate ageing. eLife 2021; 10:62233. [PMID: 33988501 PMCID: PMC8186904 DOI: 10.7554/elife.62233] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 05/13/2021] [Indexed: 01/31/2023] Open
Abstract
Age-related changes to histone levels are seen in many species. However, it is unclear whether changes to histone expression could be exploited to ameliorate the effects of ageing in multicellular organisms. Here we show that inhibition of mTORC1 by the lifespan-extending drug rapamycin increases expression of histones H3 and H4 post-transcriptionally through eIF3-mediated translation. Elevated expression of H3/H4 in intestinal enterocytes in Drosophila alters chromatin organisation, induces intestinal autophagy through transcriptional regulation, and prevents age-related decline in the intestine. Importantly, it also mediates rapamycin-induced longevity and intestinal health. Histones H3/H4 regulate expression of an autophagy cargo adaptor Bchs (WDFY3 in mammals), increased expression of which in enterocytes mediates increased H3/H4-dependent healthy longevity. In mice, rapamycin treatment increases expression of histone proteins and Wdfy3 transcription, and alters chromatin organisation in the small intestine, suggesting that the mTORC1-histone axis is at least partially conserved in mammals and may offer new targets for anti-ageing interventions.
Collapse
Affiliation(s)
- Yu-Xuan Lu
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Jennifer C Regan
- Institute of Healthy Ageing, Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Jacqueline Eßer
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Lisa F Drews
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Thomas Weinseis
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Julia Stinn
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Oliver Hahn
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Richard A Miller
- Department of Pathology, University of Michigan, Ann Arbor, United States
| | | | - Linda Partridge
- Max Planck Institute for Biology of Ageing, Cologne, Germany.,Institute of Healthy Ageing, Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| |
Collapse
|
158
|
Lee EJ, Neppl RL. Influence of Age on Skeletal Muscle Hypertrophy and Atrophy Signaling: Established Paradigms and Unexpected Links. Genes (Basel) 2021; 12:genes12050688. [PMID: 34063658 PMCID: PMC8147613 DOI: 10.3390/genes12050688] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 12/16/2022] Open
Abstract
Skeletal muscle atrophy in an inevitable occurrence with advancing age, and a consequence of disease including cancer. Muscle atrophy in the elderly is managed by a regimen of resistance exercise and increased protein intake. Understanding the signaling that regulates muscle mass may identify potential therapeutic targets for the prevention and reversal of muscle atrophy in metabolic and neuromuscular diseases. This review covers the major anabolic and catabolic pathways that regulate skeletal muscle mass, with a focus on recent progress and potential new players.
Collapse
|
159
|
Al Mahi N, Zhang EY, Sherman S, Yu JJ, Medvedovic M. Connectivity Map Analysis of a Single-Cell RNA-Sequencing -Derived Transcriptional Signature of mTOR Signaling. Int J Mol Sci 2021; 22:ijms22094371. [PMID: 33922083 PMCID: PMC8122562 DOI: 10.3390/ijms22094371] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/14/2021] [Accepted: 04/14/2021] [Indexed: 12/12/2022] Open
Abstract
In the connectivity map (CMap) approach to drug repositioning and development, transcriptional signature of disease is constructed by differential gene expression analysis between the diseased tissue or cells and the control. The negative correlation between the transcriptional disease signature and the transcriptional signature of the drug, or a bioactive compound, is assumed to indicate its ability to “reverse” the disease process. A major limitation of traditional CMaP analysis is the use of signatures derived from bulk disease tissues. Since the key driver pathways are most likely dysregulated in only a subset of cells, the “averaged” transcriptional signatures resulting from bulk analysis lack the resolution to effectively identify effective therapeutic agents. The use of single-cell RNA-seq (scRNA-seq) transcriptomic assay facilitates construction of disease signatures that are specific to individual cell types, but methods for using scRNA-seq data in the context of CMaP analysis are lacking. Lymphangioleiomyomatosis (LAM) mutations in TSC1 or TSC2 genes result in the activation of the mTOR complex 1 (mTORC1). The mTORC1 inhibitor Sirolimus is the only FDA-approved drug to treat LAM. Novel therapies for LAM are urgently needed as the disease recurs with discontinuation of the treatment and some patients are insensitive to the drug. We developed methods for constructing disease transcriptional signatures and CMaP analysis using scRNA-seq profiling and applied them in the analysis of scRNA-seq data of lung tissue from naïve and sirolimus-treated LAM patients. New methods successfully implicated mTORC1 inhibitors, including Sirolimus, as capable of reverting the LAM transcriptional signatures. The CMaP analysis mimicking standard bulk-tissue approach failed to detect any connection between the LAM signature and mTORC1 signaling. This indicates that the precise signature derived from scRNA-seq data using our methods is the crucial difference between the success and the failure to identify effective therapeutic treatments in CMaP analysis.
Collapse
Affiliation(s)
- Naim Al Mahi
- Division of Biostatistics and Bioinformatics, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA;
- AbbVie Inc., North Chicago, IL 60064, USA
| | - Erik Y. Zhang
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (E.Y.Z.); (J.J.Y.)
| | | | - Jane J. Yu
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (E.Y.Z.); (J.J.Y.)
| | - Mario Medvedovic
- Division of Biostatistics and Bioinformatics, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA;
- Department of Biomedical Informatics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
- Correspondence:
| |
Collapse
|
160
|
Abstract
The health of a cell requires proper functioning, regulation, and quality control of its organelles, the membrane-enclosed compartments inside the cell that carry out its essential biochemical tasks. Aging commonly perturbs organelle homeostasis, causing problems to cellular health that can spur the initiation and progression of degenerative diseases and related pathologies. Here, we discuss emerging evidence indicating that age-related defects in organelle homeostasis stem in part from dysfunction of the autophagy-lysosome system, a pivotal player in cellular quality control and damage clearance. We also highlight natural examples from biology where enhanced activity of the autophagy-lysosome system might be harnessed to erase age-related organelle damage, raising potential implications for cellular rejuvenation.
Collapse
|
161
|
de Lima Camillo LP, Quinlan RBA. A ride through the epigenetic landscape: aging reversal by reprogramming. GeroScience 2021; 43:463-485. [PMID: 33825176 PMCID: PMC8110674 DOI: 10.1007/s11357-021-00358-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 02/08/2021] [Indexed: 02/06/2023] Open
Abstract
Aging has become one of the fastest-growing research topics in biology. However, exactly how the aging process occurs remains unknown. Epigenetics plays a significant role, and several epigenetic interventions can modulate lifespan. This review will explore the interplay between epigenetics and aging, and how epigenetic reprogramming can be harnessed for age reversal. In vivo partial reprogramming holds great promise as a possible therapy, but several limitations remain. Rejuvenation by reprogramming is a young but rapidly expanding subfield in the biology of aging.
Collapse
|
162
|
Legon L, Rallis C. Genome-wide screens in yeast models towards understanding chronological lifespan regulation. Brief Funct Genomics 2021; 21:4-12. [PMID: 33728458 PMCID: PMC8834652 DOI: 10.1093/bfgp/elab011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/09/2021] [Accepted: 02/12/2021] [Indexed: 12/15/2022] Open
Abstract
Cellular models such as yeasts are a driving force in biogerontology studies. Their simpler genome, short lifespans and vast genetic and genomics resources make them ideal to characterise pro-ageing and anti-ageing genes and signalling pathways. Over the last three decades, yeasts have contributed to the understanding of fundamental aspects of lifespan regulation including the roles of nutrient response, global protein translation rates and quality, DNA damage, oxidative stress, mitochondrial function and dysfunction as well as autophagy. In this short review, we focus on approaches used for competitive and non-competitive cell-based screens using the budding yeast Saccharomyces cerevisiae, and the fission yeast Schizosaccharomyces pombe, for deciphering the molecular mechanisms underlying chronological ageing. Automation accompanied with appropriate computational tools allowed manipulation of hundreds of thousands of colonies, generation, processing and analysis of genome-wide lifespan data. Together with barcoding and modern mutagenesis technologies, these approaches have allowed to take decisive steps towards a global, comprehensive view of cellular ageing.
Collapse
Affiliation(s)
- Luc Legon
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Charalampos Rallis
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| |
Collapse
|
163
|
Zimmermann A, Madreiter-Sokolowski C, Stryeck S, Abdellatif M. Targeting the Mitochondria-Proteostasis Axis to Delay Aging. Front Cell Dev Biol 2021; 9:656201. [PMID: 33777963 PMCID: PMC7991595 DOI: 10.3389/fcell.2021.656201] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/22/2021] [Indexed: 01/18/2023] Open
Abstract
Human life expectancy continues to grow globally, and so does the prevalence of age-related chronic diseases, causing a huge medical and economic burden on society. Effective therapeutic options for these disorders are scarce, and even if available, are typically limited to a single comorbidity in a multifaceted dysfunction that inevitably affects all organ systems. Thus, novel therapies that target fundamental processes of aging itself are desperately needed. In this article, we summarize current strategies that successfully delay aging and related diseases by targeting mitochondria and protein homeostasis. In particular, we focus on autophagy, as a fundamental proteostatic process that is intimately linked to mitochondrial quality control. We present genetic and pharmacological interventions that effectively extend health- and life-span by acting on specific mitochondrial and pro-autophagic molecular targets. In the end, we delve into the crosstalk between autophagy and mitochondria, in what we refer to as the mitochondria-proteostasis axis, and explore the prospect of targeting this crosstalk to harness maximal therapeutic potential of anti-aging interventions.
Collapse
Affiliation(s)
- Andreas Zimmermann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.,Field of Excellence BioHealth - University of Graz, Graz, Austria
| | | | - Sarah Stryeck
- Institute of Interactive Systems and Data Science, Graz University of Technology, Graz, Austria
| | - Mahmoud Abdellatif
- Department of Cardiology, Medical University of Graz, Graz, Austria.,Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif, France.,Centre de Recherche des Cordeliers, Equipe Labellisée Par la Ligue Contre le Cancer, Université de Paris, Sorbonne Université, INSERM U1138, Institut Universitaire de France, Paris, France
| |
Collapse
|
164
|
Young ARJ, Cassidy LD, Narita M. Autophagy and senescence, converging roles in pathophysiology as seen through mouse models. Adv Cancer Res 2021; 150:113-145. [PMID: 33858595 DOI: 10.1016/bs.acr.2021.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Both senescence and autophagy have been strongly linked to aging and also cancer development. Numerous molecular, cellular, and physiological changes are known to correlate with an increasing age, yet our understanding of what underlies these changes or how they combine to give rise to the various pathologies associated with aging is still unclear. Levels of autophagy activity are known to decrease with advancing age, in a variety of organisms including mammals. Whereas senescent cells are known to accumulate in our bodies with age. Herein we review evidence from some elegant genetic mouse models linking senescence and also autophagy to aging and cancer. It is especially interesting to note the convergence in the pathological phenotypes of these two processes, senescence and autophagy, in these mouse models.
Collapse
Affiliation(s)
- Andrew R J Young
- Cancer Research UK Cambridge Research Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, United Kingdom.
| | - Liam D Cassidy
- Cancer Research UK Cambridge Research Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, United Kingdom
| | - Masashi Narita
- Cancer Research UK Cambridge Research Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, United Kingdom.
| |
Collapse
|
165
|
A transition to degeneration triggered by oxidative stress in degenerative disorders. Mol Psychiatry 2021; 26:736-746. [PMID: 33159186 PMCID: PMC7914161 DOI: 10.1038/s41380-020-00943-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 10/15/2020] [Accepted: 10/26/2020] [Indexed: 12/14/2022]
Abstract
Although the activities of many signaling pathways are dysregulated during the progression of neurodegenerative and muscle degeneration disorders, the precise sequence of cellular events leading to degeneration has not been fully elucidated. Two kinases of particular interest, the growth-promoting Tor kinase and the energy sensor AMPK, appear to show reciprocal changes in activity during degeneration, with increased Tor activity and decreased AMPK activity reported. These changes in activity have been predicted to cause degeneration by attenuating autophagy, leading to the accumulation of unfolded protein aggregates and dysfunctional mitochondria, the consequent increased production of reactive oxygen species (ROS), and ultimately oxidative damage. Here we propose that this increased ROS production not only causes oxidative damage but also ultimately induces an oxidative stress response that reactivates the redox-sensitive AMPK and activates the redox-sensitive stress kinase JNK. Activation of these kinases reactivates autophagy. Because at this late stage, cells have become filled with dysfunctional mitochondria and protein aggregates, which are autophagy targets, this autophagy reactivation induces degeneration. The mechanism proposed here emphasizes that the process of degeneration is dynamic, that dysregulated signaling pathways change over time and can transition from deleterious to beneficial and vice versa as degeneration progresses.
Collapse
|
166
|
Harrison RE, Brown MR, Strand MR. Whole blood and blood components from vertebrates differentially affect egg formation in three species of anautogenous mosquitoes. Parasit Vectors 2021; 14:119. [PMID: 33627180 PMCID: PMC7905675 DOI: 10.1186/s13071-021-04594-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/11/2021] [Indexed: 02/07/2023] Open
Abstract
Background Most female mosquitoes are anautogenous and must blood feed on a vertebrate host to produce eggs. Prior studies show that the number of eggs females lay per clutch correlates with the volume of blood ingested and that protein is the most important macronutrient for egg formation. In contrast, how whole blood, blood fractions and specific blood proteins from different vertebrates affect egg formation is less clear. Since egg formation is best understood in Aedes aegypti, we examined how blood and blood components from different vertebrates affect this species and two others: the malaria vector Anopheles gambiae and arbovirus vector Culex quinquefasciatus. Methods Adult female mosquitoes were fed blood, blood fractions and purified major blood proteins from different vertebrate hosts. Markers of reproductive response including ovary ecdysteroidogenesis, yolk deposition into oocytes and number of mature eggs produced were measured. Results Ae. aegypti, An. gambiae and C. quinquefasciatus responded differently to meals of whole blood, plasma or blood cells from human, rat, chicken and turkey hosts. We observed more similarities between the anthropophiles Ae. aegypti and An. gambiae than the ornithophile C. quinquefasciatus. Focusing on Ae. aegypti, the major plasma-derived proteins (serum albumin, fibrinogen and globulins) differentially stimulated egg formation as a function of vertebrate host source. The major blood cell protein, hemoglobin, stimulated yolk deposition when from pigs but not humans, cows or sheep. Serum albumins from different vertebrates also variably affected egg formation. Bovine serum albumin (BSA) stimulated ovary ecdysteroidogenesis, but more weakly induced digestive enzyme activities than whole blood. In contrast, BSA-derived peptides and free amino acids had no stimulatory effects on ecdysteroidogenesis or yolk deposition into oocytes. Conclusions Whole blood, blood fractions and specific blood proteins supported egg formation in three species of anautogenous mosquitoes but specific responses varied with the vertebrate source of the blood components tested.![]()
Collapse
Affiliation(s)
- Ruby E Harrison
- Department of Entomology, The University of Georgia, 120 Cedar Street, 420 Biological Sciences, Athens, GA, 30602, USA
| | - Mark R Brown
- Department of Entomology, The University of Georgia, 120 Cedar Street, 420 Biological Sciences, Athens, GA, 30602, USA
| | - Michael R Strand
- Department of Entomology, The University of Georgia, 120 Cedar Street, 420 Biological Sciences, Athens, GA, 30602, USA.
| |
Collapse
|
167
|
Bolukbasi E, Woodling NS, Ivanov DK, Adcott J, Foley A, Rajasingam A, Gittings LM, Aleyakpo B, Niccoli T, Thornton JM, Partridge L. Cell type-specific modulation of healthspan by Forkhead family transcription factors in the nervous system. Proc Natl Acad Sci U S A 2021; 118:2011491118. [PMID: 33593901 PMCID: PMC7923679 DOI: 10.1073/pnas.2011491118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Reduced activity of insulin/insulin-like growth factor signaling (IIS) increases healthy lifespan among diverse animal species. Downstream of IIS, multiple evolutionarily conserved transcription factors (TFs) are required; however, distinct TFs are likely responsible for these effects in different tissues. Here we have asked which TFs can extend healthy lifespan within distinct cell types of the adult nervous system in Drosophila Starting from published single-cell transcriptomic data, we report that forkhead (FKH) is endogenously expressed in neurons, whereas forkhead-box-O (FOXO) is expressed in glial cells. Accordingly, we find that neuronal FKH and glial FOXO exert independent prolongevity effects. We have further explored the role of neuronal FKH in a model of Alzheimer's disease-associated neuronal dysfunction, where we find that increased neuronal FKH preserves behavioral function and reduces ubiquitinated protein aggregation. Finally, using transcriptomic profiling, we identify Atg17, a member of the Atg1 autophagy initiation family, as one FKH-dependent target whose neuronal overexpression is sufficient to extend healthy lifespan. Taken together, our results underscore the importance of cell type-specific mapping of TF activity to preserve healthy function with age.
Collapse
Affiliation(s)
- Ekin Bolukbasi
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Nathaniel S Woodling
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Dobril K Ivanov
- European Bioinformatics Institute, European Molecular Biology Laboratory, Cambridge CB10 1SD, United Kingdom
- UK Dementia Research Institute, Cardiff University, Cardiff CF24 4HQ, United Kingdom
| | - Jennifer Adcott
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Andrea Foley
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Arjunan Rajasingam
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Lauren M Gittings
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Benjamin Aleyakpo
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Teresa Niccoli
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Janet M Thornton
- European Bioinformatics Institute, European Molecular Biology Laboratory, Cambridge CB10 1SD, United Kingdom
| | - Linda Partridge
- Institute of Healthy Ageing, University College London, London WC1E 6BT, United Kingdom;
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
- Department of Biological Mechanisms of Ageing, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| |
Collapse
|
168
|
Protection of nuclear DNA by lifespan-extending compounds in the yeast Saccharomyces cerevisiae. Mutat Res 2021; 822:111738. [PMID: 33578051 DOI: 10.1016/j.mrfmmm.2021.111738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/01/2020] [Accepted: 01/21/2021] [Indexed: 02/01/2023]
Abstract
DNA damage has been hypothesized to be a driving force of the aging process. At the same time, there exists multiple compounds that can extend lifespan in model organisms, such as yeast, worms, flies, and mice. One possible mechanism of action for these compounds is a protective effect against DNA damage. We investigated whether five of these lifespan-extending compounds, dinitrophenol, metformin, rapamycin, resveratrol, and spermidine, could protect nuclear DNA in the yeast Saccharomyces cerevisiae at the same doses under which they confer lifespan extension. We found that rapamycin and spermidine were able to decrease the spontaneous mutation rate at the CAN1 locus, whereas dinitrophenol, metformin, and resveratrol were able to protect yeast against CAN1 mutations induced by ethyl methanesulfonate (EMS). We also tested whether these compounds could enhance survival against EMS, ultraviolet (UV) light, or hydrogen peroxide (H2O2) insult. All five compounds conferred a protective effect against EMS, while metformin and spermidine protected yeast against UV light. Somewhat surprisingly, none of the compounds were able to afford a significant protection against H2O2, with spermidine dramatically sensitizing cells. We also examined the ability of these compounds to increase lifespan when growth-arrested by hydroxyurea; only spermidine was found to have a positive effect. Overall, our results suggest that lifespan-extending compounds may act in part by protecting nuclear DNA.
Collapse
|
169
|
Blagosklonny MV. DNA- and telomere-damage does not limit lifespan: evidence from rapamycin. Aging (Albany NY) 2021; 13:3167-3175. [PMID: 33578394 PMCID: PMC7906135 DOI: 10.18632/aging.202674] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 02/10/2021] [Indexed: 12/13/2022]
Abstract
Failure of rapamycin to extend lifespan in DNA repair mutant and telomerase-knockout mice, while extending lifespan in normal mice, indicates that neither DNA damage nor telomere shortening limits normal lifespan or causes normal aging.
Collapse
|
170
|
The potential of rapalogs to enhance resilience against SARS-CoV-2 infection and reduce the severity of COVID-19. LANCET HEALTHY LONGEVITY 2021; 2:e105-e111. [PMID: 33665645 PMCID: PMC7906698 DOI: 10.1016/s2666-7568(20)30068-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
COVID-19 disproportionately affects older people, with likelihood of severe complications and death mirroring that of other age-associated diseases. Inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) has been shown to delay or reverse many age-related phenotypes, including declining immune function. Rapamycin (sirolimus) and rapamycin derivatives are US Food and Drug Administration-approved inhibitors of mTORC1 with broad clinical utility and well established dosing and safety profiles. Based on preclinical and clinical evidence, a strong case can be made for immediate large-scale clinical trials to assess whether rapamycin and other mTORC1 inhibitors can prevent COVID-19 infection in these populations and also to determine whether these drugs can improve outcomes in patients with severe COVID-19.
Collapse
|
171
|
Lin Z, Hollinger MK, Wu Z, Sun W, Batey K, Kim J, Chen J, Feng X, Young NS. Sirolimus augments hematopoietic stem and progenitor cell regeneration following hematopoietic insults. Stem Cells 2021; 39:240-252. [PMID: 33270949 PMCID: PMC7898520 DOI: 10.1002/stem.3313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 11/17/2020] [Indexed: 04/20/2023]
Abstract
The role of mammalian target of rapamycin and its suppressor sirolimus in the regulation of hematopoietic stem and progenitor cells (HSPCs) is controversial. We show here that sirolimus enhanced regeneration of HSPCs in mice exposed to sublethal total body irradiation (TBI) and other regenerative stressors. Sorted Lin- CD150+ bone marrow cells from sirolimus-treated TBI mice had increased expression of c-Kit and other hematopoietic genes. HSPCs from sirolimus-treated TBI mice were functionally competent when tested by competitive engraftment in vivo. Postradiation regeneration of HSPCs in mice treated with sirolimus was accompanied by decreased γ-H2AX levels detected by flow cytometry and increased expression of DNA repair genes by quantitative polymerase chain reaction. Reduction of cell death and DNA damage post-radiation by sirolimus was associated with enhanced clearance of cellular reactive oxygen species (ROS) in HSPCs. Increased HSPC recovery with sirolimus was also observed in mice injected with hematoxic agents, busulfan and 5-fluorouracil. In contrast, sirolimus showed no effect on HSPCs in normal mice at steady state, but stimulated HSPC expansion in mice carrying the Wv mutation at the c-Kit locus. In human to mouse xenotransplantation, sirolimus enhanced engraftment of irradiated human CD34+ cells. In summary, our results are consistent with sirolimus' acceleration of HSPC recovery in response to hematopoietic stress, associated with reduced DNA damage and ROS. Sirolimus might have clinical application for the treatment and prevention of hematopoietic injury.
Collapse
Affiliation(s)
- Zenghua Lin
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
- Department of HematologyAffiliated Hospital of Nantong UniversityNantongJiangsuPeople's Republic of China
| | - Maile K. Hollinger
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Zhijie Wu
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Wanling Sun
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
- Department of HematologyXuanwu Hospital, Capital Medical UniversityBeijingPeople's Republic of China
| | - Kaylind Batey
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Jisoo Kim
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Jichun Chen
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Xingmin Feng
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Neal S. Young
- Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
| |
Collapse
|
172
|
Baumgartner ME, Dinan MP, Langton PF, Kucinski I, Piddini E. Proteotoxic stress is a driver of the loser status and cell competition. Nat Cell Biol 2021; 23:136-146. [PMID: 33495633 PMCID: PMC7116823 DOI: 10.1038/s41556-020-00627-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 12/17/2020] [Indexed: 01/29/2023]
Abstract
Cell competition allows winner cells to eliminate less fit loser cells in tissues. In Minute cell competition, cells with a heterozygous mutation in ribosome genes, such as RpS3+/- cells, are eliminated by wild-type cells. How cells are primed as losers is partially understood and it has been proposed that reduced translation underpins the loser status of ribosome mutant, or Minute, cells. Here, using Drosophila, we show that reduced translation does not cause cell competition. Instead, we identify proteotoxic stress as the underlying cause of the loser status for Minute competition and competition induced by mahjong, an unrelated loser gene. RpS3+/- cells exhibit reduced autophagic and proteasomal flux, accumulate protein aggregates and can be rescued from competition by improving their proteostasis. Conversely, inducing proteotoxic stress is sufficient to turn otherwise wild-type cells into losers. Thus, we propose that tissues may preserve their health through a proteostasis-based mechanism of cell competition and cell selection.
Collapse
Affiliation(s)
| | - Michael P Dinan
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
- The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, UK
- Zoology Department, University of Cambridge, Cambridge, UK
- University of Cambridge, Cambridge, UK
| | - Paul F Langton
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Iwo Kucinski
- The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, UK
- Zoology Department, University of Cambridge, Cambridge, UK
- Wellcome and MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
- Department of Haematology, University of Cambridge, Cambridge, UK
| | - Eugenia Piddini
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK.
| |
Collapse
|
173
|
The role of curcumin in aging and senescence: Molecular mechanisms. Biomed Pharmacother 2021; 134:111119. [DOI: 10.1016/j.biopha.2020.111119] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/29/2020] [Accepted: 12/04/2020] [Indexed: 12/11/2022] Open
|
174
|
Mautz BS, Lind MI, Maklakov AA. Dietary Restriction Improves Fitness of Aging Parents But Reduces Fitness of Their Offspring in Nematodes. J Gerontol A Biol Sci Med Sci 2021; 75:843-848. [PMID: 31761926 PMCID: PMC7164528 DOI: 10.1093/gerona/glz276] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Indexed: 11/14/2022] Open
Abstract
Dietary restriction (DR) is a well-established intervention to extend lifespan across taxa. Recent studies suggest that DR-driven lifespan extension can be cost-free, calling into question a central tenant of the evolutionary theory of aging. Nevertheless, boosting parental longevity can reduce offspring fitness. Such intergenerational trade-offs are often ignored but can account for the "missing costs" of longevity. Here, we use the nematode Caenorhabditis remanei to test for effects of DR by fasting on fitness of females and their offspring. Females deprived of food for 6 days indeed had increased fecundity, survival, and stress resistance after re-exposure to food compared with their counterparts with constant food access. However, offspring of DR mothers had reduced early and lifetime fecundity, slower growth rate, and smaller body size at sexual maturity. These findings support the direct trade-off between investment in soma and gametes challenging the hypothesis that increased somatic maintenance and impaired reproduction can be decoupled.
Collapse
Affiliation(s)
- Brian S Mautz
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,Department of Medicine, Division of Epidemiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, UK
| |
Collapse
|
175
|
TOR Signaling Pathway in Cardiac Aging and Heart Failure. Biomolecules 2021; 11:biom11020168. [PMID: 33513917 PMCID: PMC7911348 DOI: 10.3390/biom11020168] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 02/07/2023] Open
Abstract
Mechanistic Target of Rapamycin (mTOR) signaling is a key regulator of cellular metabolism, integrating nutrient sensing with cell growth. Over the past two decades, studies on the mTOR pathway have revealed that mTOR complex 1 controls life span, health span, and aging by modulating key cellular processes such as protein synthesis, autophagy, and mitochondrial function, mainly through its downstream substrates. Thus, the mTOR pathway regulates both physiological and pathological processes in the heart from embryonic cardiovascular development to maintenance of cardiac homeostasis in postnatal life. In this regard, the dysregulation of mTOR signaling has been linked to many age-related pathologies, including heart failure and age-related cardiac dysfunction. In this review, we highlight recent advances of the impact of mTOR complex 1 pathway and its regulators on aging and, more specifically, cardiac aging and heart failure.
Collapse
|
176
|
Zanco B, Mirth CK, Sgrò CM, Piper MDW. A dietary sterol trade-off determines lifespan responses to dietary restriction in Drosophila melanogaster females. eLife 2021; 10:e62335. [PMID: 33494859 PMCID: PMC7837700 DOI: 10.7554/elife.62335] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/16/2020] [Indexed: 01/16/2023] Open
Abstract
Diet plays a significant role in maintaining lifelong health. In particular, lowering the dietary protein: carbohydrate ratio can improve lifespan. This has been interpreted as a direct effect of these macronutrients on physiology. Using Drosophila melanogaster, we show that the role of protein and carbohydrate on lifespan is indirect, acting by altering the partitioning of limiting amounts of dietary sterols between reproduction and lifespan. Shorter lifespans in flies fed on high protein: carbohydrate diets can be rescued by supplementing their food with cholesterol. Not only does this fundamentally alter the way we interpret the mechanisms of lifespan extension by dietary restriction, these data highlight the important principle that life histories can be affected by nutrient-dependent trade-offs that are indirect and independent of the nutrients (often macronutrients) that are the focus of study. This brings us closer to understanding the mechanistic basis of dietary restriction.
Collapse
Affiliation(s)
- Brooke Zanco
- Monash University, School of Biological SciencesClaytonAustralia
| | - Christen K Mirth
- Monash University, School of Biological SciencesClaytonAustralia
| | - Carla M Sgrò
- Monash University, School of Biological SciencesClaytonAustralia
| | - Matthew DW Piper
- Monash University, School of Biological SciencesClaytonAustralia
| |
Collapse
|
177
|
The Jekyll and Hyde of Cellular Senescence in Cancer. Cells 2021; 10:cells10020208. [PMID: 33494247 PMCID: PMC7909764 DOI: 10.3390/cells10020208] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/15/2021] [Accepted: 01/17/2021] [Indexed: 01/10/2023] Open
Abstract
Cellular senescence is a state of stable cell cycle arrest that can be triggered in response to various insults and is characterized by distinct morphological hallmarks, gene expression profiles, and the senescence-associated secretory phenotype (SASP). Importantly, cellular senescence is a key component of normal physiology with tumor suppressive functions. In the last few decades, novel cancer treatment strategies exploiting pro-senescence therapies have attracted considerable interest. Recent insight, however, suggests that therapy-induced senescence (TIS) elicits cell-autonomous and non-cell-autonomous implications that potentially entail detrimental consequences, reflecting the Jekyll and Hyde nature of cancer cell senescence. In essence, the undesirable manifestations that generally culminate in inflammation, cancer stemness, senescence reversal, therapy resistance, and disease recurrence are dictated by the persistent accumulation of senescent cells and the SASP. Thus, mitigating these pro-tumorigenic effects by eliminating these cells or inhibiting their SASP production holds great promise for developing innovative therapeutic strategies. In this review, we describe the fundamental aspects and dynamics of cancer cell senescence and summarize the comprehensive research on the adverse outcomes of TIS. Furthermore, we underline the rationale and motivation of emerging senotherapeutic modalities surrounding the removal of senescent cells and the SASP to help maximize the overall efficacy of cancer therapies.
Collapse
|
178
|
Mani S, Swargiary G, Chadha R. Mitophagy impairment in neurodegenerative diseases: Pathogenesis and therapeutic interventions. Mitochondrion 2021; 57:270-293. [PMID: 33476770 DOI: 10.1016/j.mito.2021.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/23/2020] [Accepted: 01/14/2021] [Indexed: 02/07/2023]
Abstract
Neurons are specialized cells, requiring a lot of energy for its proper functioning. Mitochondria are the key cellular organelles and produce most of the energy in the form of ATP, required for all the crucial functions of neurons. Hence, the regulation of mitochondrial biogenesis and quality control is important for maintaining neuronal health. As a part of mitochondrial quality control, the aged and damaged mitochondria are removed through a selective mode of autophagy called mitophagy. However, in different pathological conditions, this process is impaired in neuronal cells and lead to a variety of neurodegenerative disease (NDD). Various studies indicate that specific protein aggregates, the characteristics of different NDDs, affect this process of mitophagy, adding to the severity and progression of diseases. Though, the detailed process of this association is yet to be explored. In light of the significant role of impaired mitophagy in NDDs, further studies have also investigated a large number of therapeutic strategies to target mitophagy in these diseases. Our current review summarizes the abnormalities in different mitophagy pathways and their association with different NDDs. We have also elaborated upon various novel therapeutic strategies and their limitations to enhance mitophagy in NDDs that may help in the management of symptoms and increasing the life expectancy of NDD patients. Thus, our study provides an overview of mitophagy in NDDs and emphasizes the need to elucidate the mechanism of impaired mitophagy prevalent across different NDDs in future research. This will help designing better treatment options with high efficacy and specificity.
Collapse
Affiliation(s)
- Shalini Mani
- Department of Biotechnology, Centre for Emerging Disease, Jaypee Institute of Information Technology, Noida, India.
| | - Geeta Swargiary
- Department of Biotechnology, Centre for Emerging Disease, Jaypee Institute of Information Technology, Noida, India
| | - Radhika Chadha
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, USA
| |
Collapse
|
179
|
Millington JW, Brownrigg GP, Chao C, Sun Z, Basner-Collins PJ, Wat LW, Hudry B, Miguel-Aliaga I, Rideout EJ. Female-biased upregulation of insulin pathway activity mediates the sex difference in Drosophila body size plasticity. eLife 2021; 10:e58341. [PMID: 33448263 PMCID: PMC7864645 DOI: 10.7554/elife.58341] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 01/11/2021] [Indexed: 12/14/2022] Open
Abstract
Nutrient-dependent body size plasticity differs between the sexes in most species, including mammals. Previous work in Drosophila showed that body size plasticity was higher in females, yet the mechanisms underlying increased female body size plasticity remain unclear. Here, we discover that a protein-rich diet augments body size in females and not males because of a female-biased increase in activity of the conserved insulin/insulin-like growth factor signaling pathway (IIS). This sex-biased upregulation of IIS activity was triggered by a diet-induced increase in stunted mRNA in females, and required Drosophila insulin-like peptide 2, illuminating new sex-specific roles for these genes. Importantly, we show that sex determination gene transformer promotes the diet-induced increase in stunted mRNA via transcriptional coactivator Spargel to regulate the male-female difference in body size plasticity. Together, these findings provide vital insight into conserved mechanisms underlying the sex difference in nutrient-dependent body size plasticity.
Collapse
Affiliation(s)
- Jason W Millington
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - George P Brownrigg
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Charlotte Chao
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Ziwei Sun
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Paige J Basner-Collins
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Lianna W Wat
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Bruno Hudry
- MRC London Institute of Medical Sciences, and Institute of Clinical Sciences, Faculty of Medicine, Imperial College LondonLondonUnited Kingdom
| | - Irene Miguel-Aliaga
- MRC London Institute of Medical Sciences, and Institute of Clinical Sciences, Faculty of Medicine, Imperial College LondonLondonUnited Kingdom
| | - Elizabeth J Rideout
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| |
Collapse
|
180
|
Yalcin G, Lee CK. The Discovery of Druggable Anti-aging Agents. Ann Geriatr Med Res 2021; 24:232-242. [PMID: 33389971 PMCID: PMC7781965 DOI: 10.4235/agmr.20.0092] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 12/30/2022] Open
Abstract
Caloric restriction (CR) has been shown to extend the lifespan of many species. Research to identify compounds that imitate the results of CR has shown extensions of both lifespan and healthspan via different mechanisms. For example, mechanistic target of rapamycin (mTOR) inhibitors such as rapamycin, phenols, and flavonoids show antioxidant characteristics, while spermidine induces autophagy. Herein, we summarize research progress and proposed mechanisms for the most well-known compounds showing lifespan-extending potential for anti-aging characteristics.
Collapse
Affiliation(s)
- Gulperi Yalcin
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Cheol-Koo Lee
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| |
Collapse
|
181
|
Build-UPS and break-downs: metabolism impacts on proteostasis and aging. Cell Death Differ 2021; 28:505-521. [PMID: 33398091 PMCID: PMC7862225 DOI: 10.1038/s41418-020-00682-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 12/30/2022] Open
Abstract
Perturbation of metabolism elicits cellular stress which profoundly modulates the cellular proteome and thus protein homeostasis (proteostasis). Consequently, changes in the cellular proteome due to metabolic shift require adaptive mechanisms by molecular protein quality control. The mechanisms vitally controlling proteostasis embrace the entire life cycle of a protein involving translational control at the ribosome, chaperone-assisted native folding, and subcellular sorting as well as proteolysis by the proteasome or autophagy. While metabolic imbalance and proteostasis decline have been recognized as hallmarks of aging and age-associated diseases, both processes are largely considered independently. Here, we delineate how proteome stability is governed by insulin/IGF1 signaling (IIS), mechanistic target of Rapamycin (TOR), 5′ adenosine monophosphate-activated protein kinase (AMPK), and NAD-dependent deacetylases (Sir2-like proteins known as sirtuins). This comprehensive overview is emphasizing the regulatory interconnection between central metabolic pathways and proteostasis, indicating the relevance of shared signaling nodes as targets for future therapeutic interventions. ![]()
Collapse
|
182
|
Mohammed I, Hollenberg MD, Ding H, Triggle CR. A Critical Review of the Evidence That Metformin Is a Putative Anti-Aging Drug That Enhances Healthspan and Extends Lifespan. Front Endocrinol (Lausanne) 2021; 12:718942. [PMID: 34421827 PMCID: PMC8374068 DOI: 10.3389/fendo.2021.718942] [Citation(s) in RCA: 105] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/15/2021] [Indexed: 12/11/2022] Open
Abstract
The numerous beneficial health outcomes associated with the use of metformin to treat patients with type 2 diabetes (T2DM), together with data from pre-clinical studies in animals including the nematode, C. elegans, and mice have prompted investigations into whether metformin has therapeutic utility as an anti-aging drug that may also extend lifespan. Indeed, clinical trials, including the MILES (Metformin In Longevity Study) and TAME (Targeting Aging with Metformin), have been designed to assess the potential benefits of metformin as an anti-aging drug. Preliminary analysis of results from MILES indicate that metformin may induce anti-aging transcriptional changes; however it remains controversial as to whether metformin is protective in those subjects free of disease. Furthermore, despite clinical use for over 60 years as an anti-diabetic drug, the cellular mechanisms by which metformin exerts either its actions remain unclear. In this review, we have critically evaluated the literature that has investigated the effects of metformin on aging, healthspan and lifespan in humans as well as other species. In preparing this review, particular attention has been placed on the strength and reproducibility of data and quality of the study protocols with respect to the pharmacokinetic and pharmacodynamic properties of metformin. We conclude that despite data in support of anti-aging benefits, the evidence that metformin increases lifespan remains controversial. However, via its ability to reduce early mortality associated with various diseases, including diabetes, cardiovascular disease, cognitive decline and cancer, metformin can improve healthspan thereby extending the period of life spent in good health. Based on the available evidence we conclude that the beneficial effects of metformin on aging and healthspan are primarily indirect via its effects on cellular metabolism and result from its anti-hyperglycemic action, enhancing insulin sensitivity, reduction of oxidative stress and protective effects on the endothelium and vascular function.
Collapse
Affiliation(s)
- Ibrahim Mohammed
- Department of Medical Education, Weill Cornell Medicine-Qatar, Al-Rayyan, Qatar
- *Correspondence: Chris R. Triggle, ; Ibrahim Mohammed,
| | - Morley D. Hollenberg
- Inflammation Research Network and Snyder Institute for Chronic Diseases, Department of Physiology & Pharmacology, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
- Department of Medicine, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
| | - Hong Ding
- Department of Medical Education, Weill Cornell Medicine-Qatar, Al-Rayyan, Qatar
- Departments of Medical Education and Pharmacology, Weill Cornell Medicine-Qatar, Al-Rayyan, Qatar
| | - Chris R. Triggle
- Department of Medical Education, Weill Cornell Medicine-Qatar, Al-Rayyan, Qatar
- Departments of Medical Education and Pharmacology, Weill Cornell Medicine-Qatar, Al-Rayyan, Qatar
- *Correspondence: Chris R. Triggle, ; Ibrahim Mohammed,
| |
Collapse
|
183
|
The dialogue between the ubiquitin-proteasome system and autophagy: Implications in ageing. Ageing Res Rev 2020; 64:101203. [PMID: 33130248 DOI: 10.1016/j.arr.2020.101203] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/09/2020] [Accepted: 10/25/2020] [Indexed: 02/06/2023]
Abstract
Dysregulated proteostasis is one of the hallmarks of ageing. Damaged proteins may impair cellular function and their accumulation may lead to tissue dysfunction and disease. This is why protective mechanisms to safeguard the cell proteome have evolved. These mechanisms consist of cellular machineries involved in protein quality control, including regulators of protein translation, folding, trafficking and degradation. In eukaryotic cells, protein degradation occurs via two main pathways: the ubiquitin-proteasome system (UPS) and the autophagy-lysosome pathway. Although distinct pathways, they are not isolated systems and have a complementary nature, as evidenced by recent studies. These findings raise the question of how autophagy and the proteasome crosstalk. In this review we address how the two degradation pathways impact each other, thereby adding a new layer of regulation to protein degradation. We also analyze the implications of the UPS and autophagy in ageing.
Collapse
|
184
|
Muhedier M, Li J, Liu H, Ma G, Amahong K, Lin R, Lü G. Tacrolimus, a rapamycin target protein inhibitor, exerts anti-cystic echinococcosis effects both in vitro and in vivo. Acta Trop 2020; 212:105708. [PMID: 32956634 DOI: 10.1016/j.actatropica.2020.105708] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 08/27/2020] [Accepted: 09/11/2020] [Indexed: 12/12/2022]
Abstract
In view of a growing need for new treatment options for human cystic echinococcosis (CE), we aimed to investigate the efficacy of mTOR pathway inhibitors against CE in vitro and in vivo. Among the seven mTOR inhibitors evaluated, tacrolimus (TAC) showed significant dose- and time-dependent killing of cultured protoscoleces and cysts in vitro. Notably, the oral administration of TAC (4 mg/kg/day) to CE mice model highly effectively reduced both the weight and number of parasitic cysts. Transmission electron microscopy revealed that TAC destroys the ultrastructure of cysts, both in vitro and in vivo. Furthermore, TAC had no significant effect on blood glucose, body weight, liver, or kidney functions in mice. We further observed that the ATP levels and glucose content of cysts reduced upon TAC treatment, indicating that inhibiting mTORC1 activity possibly affects glucose metabolism in the cysts of mice. Based on our experimental data, TAC emerged as a promising anti-cyst drug that efficiently inhibits the growth of cysts.
Collapse
Affiliation(s)
- Muzhabaier Muhedier
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China; Kashi maternal and child health care hospital, Kashi, Xinjiang, China
| | - Jintian Li
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China; College of pharmacy, Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Hui Liu
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Guizhi Ma
- College of pharmacy, Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Kuerbannisha Amahong
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Renyong Lin
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China.
| | - Guodong Lü
- State Key Laboratory of Pathogenesis, Prevention, and Treatment of Central Asian High Incidence Diseases, Clinical Medical Research Institute, First Affiliated Hospital of Xinjiang Medical University, China; Xinjiang Key Laboratory of Echinococcosis, Clinical Medicine Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China; College of pharmacy, Xinjiang Medical University, Urumqi, Xinjiang, China.
| |
Collapse
|
185
|
Lu J, Temp U, Müller-Hartmann A, Esser J, Grönke S, Partridge L. Sestrin is a key regulator of stem cell function and lifespan in response to dietary amino acids. ACTA ACUST UNITED AC 2020; 1:60-72. [PMID: 37117991 DOI: 10.1038/s43587-020-00001-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/17/2020] [Indexed: 01/10/2023]
Abstract
Dietary restriction (DR) promotes healthy aging in diverse species. Essential amino acids play a key role, but the molecular mechanisms are unknown. The evolutionarily conserved Sestrin protein, an inhibitor of activity of the target of rapamycin complex 1 (TORC1), has recently been discovered as a sensor of amino acids in vitro. Here, we show that Sestrin null mutant flies have a blunted response of lifespan to DR. A mutant Sestrin fly line, with blocked amino acid binding and TORC1 activation, showed delayed development, reduced fecundity, extended lifespan and protection against lifespan-shortening, high-protein diets. Sestrin mediated reduced intestinal stem cell activity and gut cell turnover from DR, and stem cell proliferation in response to dietary amino acids, by regulating the TOR pathway and autophagy. Sestrin expression in intestinal stem cells was sufficient to maintain gut homeostasis and extend lifespan. Sestrin is thus a molecular link between dietary amino acids, stem cell function and longevity.
Collapse
|
186
|
Moretti CH, Schiffer TA, Montenegro MF, Larsen FJ, Tsarouhas V, Carlström M, Samakovlis C, Weitzberg E, Lundberg JO. Dietary nitrite extends lifespan and prevents age-related locomotor decline in the fruit fly. Free Radic Biol Med 2020; 160:860-870. [PMID: 32980539 DOI: 10.1016/j.freeradbiomed.2020.09.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/24/2020] [Accepted: 09/14/2020] [Indexed: 02/08/2023]
Abstract
Aging is associated with decreased nitric oxide (NO) bioavailability and signalling. Boosting of a dietary nitrate-nitrite-NO pathway e.g. by ingestion of leafy green vegetables, improves cardiometabolic function, mitochondrial efficiency and reduces oxidative stress in humans and rodents, making dietary nitrate and nitrite an appealing intervention to address age-related disorders. On the other hand, these anions have long been implicated in detrimental health effects of our diet, particularly in formation of carcinogenic nitrosamines. The aim of this study was to assess whether inorganic nitrite affects lifespan in Drosophila melanogaster and investigate possible mechanisms underlying any such effect. In a survival assay, female flies fed a nitrite supplemented diet showed lifespan extension by 9 and 15% with 0.1 and 1 μM nitrite respectively, with no impact of nitrite on reproductive output. Interestingly, nitrite could also protect female flies from age-dependent locomotor decline, indicating a protective effect on healthspan. NO generation from nitrite involved Drosophila commensal bacteria and was indicated by a fluorescent probe as well as direct measurements of NO gas formation with chemiluminescence. Nutrient sensing pathways such as TOR and sirtuins, have been strongly implicated in lifespan extension. In aged flies, nitrite supplementation significantly downregulated dTOR and upregulated dSir2 gene expression. Total triglycerides and glucose were decreased, a described downstream effect of both TOR and sirtuin pathways. In conclusion, we demonstrate that very low doses of dietary nitrite extend lifespan and favour healthspan in female flies. We propose modulation of nutrient sensing pathways as driving mechanisms for such effects.
Collapse
Affiliation(s)
- Chiara H Moretti
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden.
| | - Tomas A Schiffer
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Marcelo F Montenegro
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Filip J Larsen
- The Swedish School of Sport and Health Sciences, Stockholm, 114 86, Sweden
| | - Vasilios Tsarouhas
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm, 106 91, Sweden
| | - Mattias Carlström
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Christos Samakovlis
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm, 106 91, Sweden
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Jon O Lundberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, 171 77, Sweden.
| |
Collapse
|
187
|
Cui L, Song W, Zeng Y, Wu Q, Fan Z, Huang T, Zeng B, Zhang M, Ni Q, Li Y, Wang T, Li D, Mao X, Lian T, Yang D, Yang M, Fan X. Deubiquitinase USP7 regulates Drosophila aging through ubiquitination and autophagy. Aging (Albany NY) 2020; 12:23082-23095. [PMID: 33221768 PMCID: PMC7746378 DOI: 10.18632/aging.104067] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 08/14/2020] [Indexed: 02/04/2023]
Abstract
Ubiquitination-mediated protein degradation is the selective degradation of diverse forms of damaged proteins that are tagged with ubiquitin, while deubiquitinating enzymes reverse ubiquitination-mediated protein degradation by removing the ubiquitin chain from the target protein. The interactions of ubiquitinating and deubiquitinating enzymes are required to maintain protein homeostasis. The ubiquitin-specific protease USP7 is a deubiquitinating enzyme that indirectly plays a role in repairing DNA damage and development. However, the mechanism of its participation in aging has not been fully explored. Regarding this issue, we found that USP7 was necessary to maintain the normal lifespan of Drosophila melanogaster, and knockdown of dusp7 shortened the lifespan and reduced the ability of Drosophila to cope with starvation, oxidative stress and heat stress. Furthermore, we showed that the ability of USP7 to regulate aging depends on the autophagy and ubiquitin signaling pathways. Furthermore, 2,5-dimethyl-celecoxib (DMC), a derivative of celecoxib, can partially restore the shortened lifespan and aberrant phenotypes caused by dusp7 knockdown. Our results suggest that USP7 is an important factor involved in the regulation of aging, and related components in this regulatory pathway may become new targets for anti-aging treatments.
Collapse
Affiliation(s)
- Lang Cui
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Wenhao Song
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Yao Zeng
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Qi Wu
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Ziqiang Fan
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Tiantian Huang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Bo Zeng
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mingwang Zhang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qingyong Ni
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yan Li
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Tao Wang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Diyan Li
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xueping Mao
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Ting Lian
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Deying Yang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mingyao Yang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiaolan Fan
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| |
Collapse
|
188
|
Yee Z, Lim SHY, Ng LF, Gruber J. Inhibition of mTOR decreases insoluble proteins burden by reducing translation in C. elegans. Biogerontology 2020; 22:101-118. [PMID: 33159806 DOI: 10.1007/s10522-020-09906-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/02/2020] [Indexed: 02/07/2023]
Abstract
Aging animals accumulate insoluble proteins as a consequence of a decline of proteostatic maintenance with age. In Caenorhabditis elegans, for instance, levels of detergent-insoluble proteins increase with age. In longer-lived strains of C. elegans, this accumulation occurs more slowly, implying a link to lifespan determination. We further explored this link and found that detergent-insoluble proteins accumulate more rapidly at higher temperatures, a condition where lifespan is short. We employed a C. elegans strain carrying a GFP transcriptional reporter under the control of a heat shock (hsp-16.2) promoter to investigate the dynamics of proteostatic failure in individual nematodes. We found that early, sporadic activation of hsp-16.2 was predictive of shorter remaining lifespan in individual nematodes. Exposure to rapamycin, resulting in reduced mTOR signaling, delayed spurious expression, extended lifespan, and delayed accumulation of insoluble proteins, suggesting that targets downstream of the mTOR pathway regulate the accumulation of insoluble proteins. We specifically explored ribosomal S6 kinase (rsks-1) as one such candidate and found that RNAi against rsks-1 also resulted in less age-dependent accumulation of insoluble proteins and extended lifespan. Our results demonstrate that inhibition of protein translation via reduced mTOR signaling resulted in slower accumulation of insoluble proteins, delayed proteostatic crisis, and extended lifespan in C. elegans.
Collapse
Affiliation(s)
- Zhuangli Yee
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Shaun Hsien Yang Lim
- Aging Research Laboratory, Science Division, Yale-NUS College, Singapore, Singapore
| | - Li Fang Ng
- Aging Research Laboratory, Science Division, Yale-NUS College, Singapore, Singapore
| | - Jan Gruber
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore. .,Aging Research Laboratory, Science Division, Yale-NUS College, Singapore, Singapore.
| |
Collapse
|
189
|
Garratt M. Why do sexes differ in lifespan extension? Sex-specific pathways of aging and underlying mechanisms for dimorphic responses. ACTA ACUST UNITED AC 2020. [DOI: 10.3233/nha-190067] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Males and females typically have different lifespans and frequently differ in their responses to anti-aging interventions. These sex-specific responses are documented in mice and Drosophila species, in addition to other organisms where interventions have been tested. While the prevalence of sex-specific responses to anti-aging interventions is now recognised, the underlying causes remain poorly understood. This review first summarises the main pathways and interventions that lead to sex-specific lifespan responses, including the growth-hormone/insulin-like growth factor 1 (GH-IGF1) axis, mechanistic target of rapamycin (mTOR) signalling, and nutritional and pharmacological interventions. After summarising current evidence, several different potential causes for sex-specific responses are discussed. These include sex-differences in xenobiotic metabolism, differing disease susceptibility, sex-specific hormone production and chromosomes, and the relative importance of different signalling pathways in the control of male and female life-history. Understanding why sex-differences in lifespan-extension occur should provide a greater understanding of the mechanisms that regulate the aging process in each sex, and will be crucial for understanding the full implications of these treatments if they are translated to humans.
Collapse
Affiliation(s)
- Michael Garratt
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| |
Collapse
|
190
|
Fang Y, Gong AY, Haller ST, Dworkin LD, Liu Z, Gong R. The ageing kidney: Molecular mechanisms and clinical implications. Ageing Res Rev 2020; 63:101151. [PMID: 32835891 PMCID: PMC7595250 DOI: 10.1016/j.arr.2020.101151] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 12/11/2022]
Abstract
As human life expectancy keeps increasing, ageing populations present a growing challenge for clinical practices. Human ageing is associated with molecular, structural, and functional changes in a variety of organ systems, including the kidney. During the ageing process, the kidney experiences progressive functional decline as well as macroscopic and microscopic histological alterations, which are accentuated by systemic comorbidities like hypertension and diabetes mellitus, or by preexisting or underlying kidney diseases. Although ageing per se does not cause kidney injury, physiologic changes associated with normal ageing processes are likely to impair the reparative capacity of the kidney and thus predispose older people to acute kidney disease, chronic kidney disease and other renal diseases. Mechanistically, cell senescence plays a key role in renal ageing, involving a number of cellular signaling mechanisms, many of which may be harnessed as international targets for slowing or even reversing kidney ageing. This review summarizes the clinical characteristics of renal ageing, highlights the latest progresses in deciphering the role of cell senescence in renal ageing, and envisages potential interventional strategies and novel therapeutic targets for preventing or improving renal ageing in the hope of maintaining long-term kidney health and function across the life course.
Collapse
Affiliation(s)
- Yudong Fang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China; Division of Nephrology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Athena Y Gong
- Division of Nephrology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Steven T Haller
- Division of Cardiology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Lance D Dworkin
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Zhangsuo Liu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Rujun Gong
- Division of Nephrology, University of Toledo College of Medicine, Toledo, Ohio, USA; Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA; Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, Ohio, USA.
| |
Collapse
|
191
|
Holczer M, Hajdú B, Lőrincz T, Szarka A, Bánhegyi G, Kapuy O. Fine-tuning of AMPK-ULK1-mTORC1 regulatory triangle is crucial for autophagy oscillation. Sci Rep 2020; 10:17803. [PMID: 33082544 PMCID: PMC7576158 DOI: 10.1038/s41598-020-75030-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 09/28/2020] [Indexed: 12/17/2022] Open
Abstract
Autophagy is an intracellular digestive process, which has a crucial role in maintaining cellular homeostasis by self-eating the unnecessary and/or damaged components of the cell at various stress events. ULK1, one of the key elements of autophagy activator complex, together with the two sensors of nutrient and energy conditions, called mTORC1 and AMPK kinases, guarantee the precise function of cell response mechanism. We claim that the feedback loops of AMPK-mTORC1-ULK1 regulatory triangle determine an accurate dynamical characteristic of autophagic process upon cellular stress. By using both molecular and theoretical biological techniques, here we reveal that a delayed negative feedback loop between active AMPK and ULK1 is essential to manage a proper cellular answer after prolonged starvation or rapamycin addition. AMPK kinase quickly gets induced followed by AMPK-P-dependent ULK1 activation, whereas active ULK1 has a rapid negative effect on AMPK-P resulting in a delayed inhibition of ULK1. The AMPK-P → ULK1 ˧ AMPK-P negative feedback loop results in a periodic repeat of their activation and inactivation and an oscillatory activation of autophagy, as well. We demonstrate that the periodic induction of self-cannibalism is necessary for the proper dynamical behaviour of the control network when mTORC1 is inhibited with respect to various stress events. By computational simulations we also suggest various scenario to introduce "delay" on AMPK-P-dependent ULK1 activation (i.e. extra regulatory element in the wiring diagram or multi-phosphorylation of ULK1).
Collapse
Affiliation(s)
- Marianna Holczer
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Tűzoltó utca 37-47, Budapest, 1094, Hungary
| | - Bence Hajdú
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Tűzoltó utca 37-47, Budapest, 1094, Hungary
| | - Tamás Lőrincz
- Laboratory of Biochemistry and Molecular Biology, Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, Budapest, Hungary
| | - András Szarka
- Laboratory of Biochemistry and Molecular Biology, Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, Budapest, Hungary
| | - Gábor Bánhegyi
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Tűzoltó utca 37-47, Budapest, 1094, Hungary.,Pathobiochemistry Research Group of the Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Orsolya Kapuy
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Tűzoltó utca 37-47, Budapest, 1094, Hungary.
| |
Collapse
|
192
|
Wang S, Meyer DH, Schumacher B. H3K4me2 regulates the recovery of protein biosynthesis and homeostasis following DNA damage. Nat Struct Mol Biol 2020; 27:1165-1177. [DOI: 10.1038/s41594-020-00513-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 09/02/2020] [Indexed: 01/08/2023]
|
193
|
Lombard DB, Kohler WJ, Guo AH, Gendron C, Han M, Ding W, Lyu Y, Ching TT, Wang FY, Chakraborty TS, Nikolovska-Coleska Z, Duan Y, Girke T, Hsu AL, Pletcher SD, Miller RA. High-throughput small molecule screening reveals Nrf2-dependent and -independent pathways of cellular stress resistance. SCIENCE ADVANCES 2020; 6:6/40/eaaz7628. [PMID: 33008901 PMCID: PMC7852388 DOI: 10.1126/sciadv.aaz7628] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 08/14/2020] [Indexed: 05/03/2023]
Abstract
Aging is the dominant risk factor for most chronic diseases. Development of antiaging interventions offers the promise of preventing many such illnesses simultaneously. Cellular stress resistance is an evolutionarily conserved feature of longevity. Here, we identify compounds that induced resistance to the superoxide generator paraquat (PQ), the heavy metal cadmium (Cd), and the DNA alkylator methyl methanesulfonate (MMS). Some rescue compounds conferred resistance to a single stressor, while others provoked multiplex resistance. Induction of stress resistance in fibroblasts was predictive of longevity extension in a published large-scale longevity screen in Caenorhabditis elegans, although not in testing performed in worms and flies with a more restricted set of compounds. Transcriptomic analysis and genetic studies implicated Nrf2/SKN-1 signaling in stress resistance provided by two protective compounds, cardamonin and AEG 3482. Small molecules identified in this work may represent attractive tools to elucidate mechanisms of stress resistance in mammalian cells.
Collapse
Affiliation(s)
- David B Lombard
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA.
- Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - William J Kohler
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Angela H Guo
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Christi Gendron
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Melissa Han
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Weiqiao Ding
- Department of Internal Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Yang Lyu
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Tsui-Ting Ching
- Institute of Biopharmaceutical Sciences, National Yang Ming University, Taipei 112, Taiwan
| | - Feng-Yung Wang
- Institute of Biochemistry and Molecular Biology, National Yang Ming University, Taipei 112, Taiwan
| | - Tuhin S Chakraborty
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Yuzhu Duan
- Institute for Integrative Genome Biology, University of California Riverside, Riverside, CA, USA
| | - Thomas Girke
- Institute for Integrative Genome Biology, University of California Riverside, Riverside, CA, USA
| | - Ao-Lin Hsu
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Internal Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, MI, USA
- Research Center for Healthy Aging, China Medical University, Taichung, Taiwan
| | - Scott D Pletcher
- Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Richard A Miller
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
- Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
194
|
Woodling NS, Rajasingam A, Minkley LJ, Rizzo A, Partridge L. Independent glial subtypes delay development and extend healthy lifespan upon reduced insulin-PI3K signalling. BMC Biol 2020; 18:124. [PMID: 32928209 PMCID: PMC7490873 DOI: 10.1186/s12915-020-00854-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 08/21/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The increasing age of global populations highlights the urgent need to understand the biological underpinnings of ageing. To this end, inhibition of the insulin/insulin-like signalling (IIS) pathway can extend healthy lifespan in diverse animal species, but with trade-offs including delayed development. It is possible that distinct cell types underlie effects on development and ageing; cell-type-specific strategies could therefore potentially avoid negative trade-offs when targeting diseases of ageing, including prevalent neurodegenerative diseases. The highly conserved diversity of neuronal and non-neuronal (glial) cell types in the Drosophila nervous system makes it an attractive system to address this possibility. We have thus investigated whether IIS in distinct glial cell populations differentially modulates development and lifespan in Drosophila. RESULTS We report here that glia-specific IIS inhibition, using several genetic means, delays development while extending healthy lifespan. The effects on lifespan can be recapitulated by adult-onset IIS inhibition, whereas developmental IIS inhibition is dispensable for modulation of lifespan. Notably, the effects we observe on both lifespan and development act through the PI3K branch of the IIS pathway and are dependent on the transcription factor FOXO. Finally, IIS inhibition in several glial subtypes can delay development without extending lifespan, whereas the same manipulations in astrocyte-like glia alone are sufficient to extend lifespan without altering developmental timing. CONCLUSIONS These findings reveal a role for distinct glial subpopulations in the organism-wide modulation of development and lifespan, with IIS in astrocyte-like glia contributing to lifespan modulation but not to developmental timing. Our results enable a more complete picture of the cell-type-specific effects of the IIS network, a pathway whose evolutionary conservation in humans make it tractable for therapeutic interventions. Our findings therefore underscore the necessity for cell-type-specific strategies to optimise interventions for the diseases of ageing.
Collapse
Affiliation(s)
- Nathaniel S Woodling
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Arjunan Rajasingam
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Lucy J Minkley
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Alberto Rizzo
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Linda Partridge
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK.
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931, Cologne, Germany.
| |
Collapse
|
195
|
Bjedov I, Rallis C. The Target of Rapamycin Signalling Pathway in Ageing and Lifespan Regulation. Genes (Basel) 2020; 11:E1043. [PMID: 32899412 PMCID: PMC7565554 DOI: 10.3390/genes11091043] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 12/11/2022] Open
Abstract
Ageing is a complex trait controlled by genes and the environment. The highly conserved mechanistic target of rapamycin signalling pathway (mTOR) is a major regulator of lifespan in all eukaryotes and is thought to be mediating some of the effects of dietary restriction. mTOR is a rheostat of energy sensing diverse inputs such as amino acids, oxygen, hormones, and stress and regulates lifespan by tuning cellular functions such as gene expression, ribosome biogenesis, proteostasis, and mitochondrial metabolism. Deregulation of the mTOR signalling pathway is implicated in multiple age-related diseases such as cancer, neurodegeneration, and auto-immunity. In this review, we briefly summarise some of the workings of mTOR in lifespan and ageing through the processes of transcription, translation, autophagy, and metabolism. A good understanding of the pathway's outputs and connectivity is paramount towards our ability for genetic and pharmacological interventions for healthy ageing and amelioration of age-related disease.
Collapse
Affiliation(s)
- Ivana Bjedov
- UCL Cancer Institute, Paul O’Gorman Building, 72 Huntley Street, London WC1E 6DD, UK
| | - Charalampos Rallis
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| |
Collapse
|
196
|
Fedintsev A, Moskalev A. Stochastic non-enzymatic modification of long-lived macromolecules - A missing hallmark of aging. Ageing Res Rev 2020; 62:101097. [PMID: 32540391 DOI: 10.1016/j.arr.2020.101097] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/05/2020] [Accepted: 06/04/2020] [Indexed: 12/12/2022]
Abstract
Damage accumulation in long-living macromolecules (especially extracellular matrix (ECM) proteins, nuclear pore complex (NPC) proteins, and histones) is a missing hallmark of aging. Stochastic non-enzymatic modifications of ECM trigger cellular senescence as well as many other hallmarks of aging affect organ barriers integrity and drive tissue fibrosis. The importance of it for aging makes it a key target for interventions. The most promising of them can be AGE inhibitors (chelators, O-acetyl group or transglycating activity compounds, amadorins and amadoriases), glucosepane breakers, stimulators of elastogenesis, and RAGE antagonists.
Collapse
Affiliation(s)
- Alexander Fedintsev
- Institute of Biology of FRC of Komi Scientific Center, Ural Branch of Russian Academy of Sciences, Syktyvkar, Russia
| | - Alexey Moskalev
- Institute of Biology of FRC of Komi Scientific Center, Ural Branch of Russian Academy of Sciences, Syktyvkar, Russia.
| |
Collapse
|
197
|
Soo SK, Rudich PD, Traa A, Harris-Gauthier N, Shields HJ, Van Raamsdonk JM. Compounds that extend longevity are protective in neurodegenerative diseases and provide a novel treatment strategy for these devastating disorders. Mech Ageing Dev 2020; 190:111297. [PMID: 32610099 PMCID: PMC7484136 DOI: 10.1016/j.mad.2020.111297] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 12/13/2022]
Abstract
While aging is the greatest risk factor for the development of neurodegenerative disease, the role of aging in these diseases is poorly understood. In the inherited forms of these diseases, the disease-causing mutation is present from birth but symptoms appear decades later. This indicates that these mutations are well tolerated in younger individuals but not in older adults. Based on this observation, we hypothesized that changes taking place during normal aging make the cells in the brain (and elsewhere) susceptible to the disease-causing mutations. If so, then delaying some of these age-related changes may be beneficial in the treatment of neurodegenerative disease. In this review, we examine the effects of five compounds that have been shown to extend longevity (metformin, rapamycin, resveratrol, N-acetyl-l-cysteine, curcumin) in four of the most common neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis). While not all investigations observe a beneficial effect of these compounds, there are multiple studies that show a protective effect of each of these lifespan-extending compounds in animal models of neurodegenerative disease. Combined with genetic studies, this suggests the possibility that targeting the aging process may be an effective strategy to treat neurodegenerative disease.
Collapse
Affiliation(s)
- Sonja K Soo
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada
| | - Paige D Rudich
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada
| | - Annika Traa
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada
| | - Namasthée Harris-Gauthier
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada
| | - Hazel J Shields
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada
| | - Jeremy M Van Raamsdonk
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, H4A 3J1, Canada; Metabolic Disorders and Complications Program, and Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, QC, H4A 3J1, Canada; Division of Experimental Medicine, Department of Medicine, McGill University, Montreal, QC, H4A 3J1, Canada; Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA.
| |
Collapse
|
198
|
Sontowski R, van Dam NM. Functional Variation in Dipteran Gut Bacterial Communities in Relation to Their Diet, Life Cycle Stage and Habitat. INSECTS 2020; 11:insects11080543. [PMID: 32824605 PMCID: PMC7469148 DOI: 10.3390/insects11080543] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/05/2020] [Accepted: 08/11/2020] [Indexed: 12/12/2022]
Abstract
Simple Summary Like in many other organisms, the guts of insects are full with many different bacteria. These bacteria can help their hosts to overcome toxic diets or can boost their resistance to pathogens. We were curious to learn which factors determine the composition of gut bacterial communities (GBCs) in true flies and mosquitoes, which belong to the order Diptera. We searched for research papers reporting on GBCs in these insects. Using these published data, we investigated whether the GBCs are species-specific, or whether they are determined by the diet, life stage or environment of the host insect. We found that the GBCs in larvae and adults of the same insect species can be very different. Insects on similar diets did not necessarily show similar GBCs. This made us conclude that GBCs are mostly life stage-specific. However, we found that the number of data papers we could use is limited; more data are needed to strengthen our conclusion. Lastly, novel DNA technologies can show ‘who is there’ in GBCs. At the same time, we lack knowledge on the exact function of gut bacteria. Obtaining more knowledge on the function of GBCs may help to design sustainable pest control measures. Abstract True flies and mosquitos (Diptera) live in habitats and consume diets that pose specific demands on their gut bacterial communities (GBCs). Due to diet specializations, dipterans may have highly diverse and species-specific GBCs. Dipterans are also confronted with changes in habitat and food sources over their lifetime, especially during life history processes (molting, metamorphosis). This may prevent the development of a constant species- or diet-specific GBC. Some dipterans are vectors of several human pathogens (e.g., malaria), which interact with GBCs. In this review, we explore the dynamics that shape GBC composition in some Diptera species on the basis of published datasets of GBCs. We thereby focus on the effects of diet, habitats, and life cycle stages as sources of variation in GBC composition. The GBCs reported were more stage-specific than species- or diet-specific. Even though the presence of GBCs has a large impact on the performance of their hosts, the exact functions of GBCs and their interactions with other organisms are still largely unknown, mainly due to the low number of studies to date. Increasing our knowledge on dipteran GBCs will help to design pest management strategies for the reduction of insecticide resistance, as well as for human pathogen control.
Collapse
Affiliation(s)
- Rebekka Sontowski
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany;
- Institute for Biodiversity, Friedrich-Schiller University, Dornburger Str. 159, 07743 Jena, Germany
- Correspondence:
| | - Nicole M. van Dam
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany;
- Institute for Biodiversity, Friedrich-Schiller University, Dornburger Str. 159, 07743 Jena, Germany
| |
Collapse
|
199
|
Juricic P, Grönke S, Partridge L. Branched-Chain Amino Acids Have Equivalent Effects to Other Essential Amino Acids on Lifespan and Aging-Related Traits in Drosophila. J Gerontol A Biol Sci Med Sci 2020; 75:24-31. [PMID: 30891588 PMCID: PMC6909895 DOI: 10.1093/gerona/glz080] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Indexed: 11/30/2022] Open
Abstract
Branched-chain amino acids (BCAAs) have been suggested to be particularly potent activators of Target of Rapamycin (TOR) signaling. Moreover, increased circulating BCAAs are associated with higher risk of insulin resistance and diabetes in both mice and humans, and with increased mortality in mice. However, it remains unknown if BCAAs play a more prominent role in longevity than do other essential amino acids (EAAs). To test for a more prominent role of BCAAs in lifespan and related traits in Drosophila, we restricted either BCAAs or a control group of three other EAAs, threonine, histidine and lysine (THK). BCAA restriction induced compensatory feeding, lipid accumulation, stress resistance and amelioration of age-related gut pathology. It also extended lifespan in a dietary-nitrogen-dependent manner. Importantly, the control restriction of THK had similar effects on these phenotypes. Our control diet was designed to have every EAA equally limiting for growth and reproduction, and our findings therefore suggest that the level of the most limiting EAAs in the diet, rather than the specific EAAs that are limiting, determines the response of these phenotypes to EAA restriction.
Collapse
Affiliation(s)
- Paula Juricic
- Max Planck Institute for Biology of Ageing, and Department of Biological Mechanisms of Ageing, Cologne, Germany
| | - Sebastian Grönke
- Max Planck Institute for Biology of Ageing, and Department of Biological Mechanisms of Ageing, Cologne, Germany
| | - Linda Partridge
- Max Planck Institute for Biology of Ageing, and Department of Biological Mechanisms of Ageing, Cologne, Germany.,Institute of Healthy Ageing, and Department of Genetics, Evolution and Environment, UCL, London, UK
| |
Collapse
|
200
|
Catalani E, Bongiorni S, Taddei AR, Mezzetti M, Silvestri F, Coazzoli M, Zecchini S, Giovarelli M, Perrotta C, De Palma C, Clementi E, Ceci M, Prantera G, Cervia D. Defects of full-length dystrophin trigger retinal neuron damage and synapse alterations by disrupting functional autophagy. Cell Mol Life Sci 2020; 78:1615-1636. [PMID: 32749504 PMCID: PMC7904721 DOI: 10.1007/s00018-020-03598-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 06/10/2020] [Accepted: 07/09/2020] [Indexed: 02/06/2023]
Abstract
Dystrophin (dys) mutations predispose Duchenne muscular disease (DMD) patients to brain and retinal complications. Although different dys variants, including long dys products, are expressed in the retina, their function is largely unknown. We investigated the putative role of full-length dystrophin in the homeostasis of neuro-retina and its impact on synapsis stabilization and cell fate. Retinas of mdx mice, the most used DMD model which does not express the 427-KDa dys protein (Dp427), showed overlapped cell death and impaired autophagy. Apoptotic neurons in the outer plexiform/inner nuclear layer and the ganglion cell layer had an impaired autophagy with accumulated autophagosomes. The autophagy dysfunction localized at photoreceptor axonal terminals and bipolar, amacrine, and ganglion cells. The absence of Dp427 does not cause a severe phenotype but alters the neuronal architecture, compromising mainly the pre-synaptic photoreceptor terminals and their post-synaptic sites. The analysis of two dystrophic mutants of the fruit fly Drosophila melanogaster, the homozygous DysE17 and DysEP3397, lacking functional large-isoforms of dystrophin-like protein, revealed rhabdomere degeneration. Structural damages were evident in the internal network of retina/lamina where photoreceptors make the first synapse. Both accumulated autophagosomes and apoptotic features were detected and the visual system was functionally impaired. The reactivation of the autophagosome turnover by rapamycin prevented neuronal cell death and structural changes of mutant flies and, of interest, sustained autophagy ameliorated their response to light. Overall, these findings indicate that functional full-length dystrophin is required for synapsis stabilization and neuronal survival of the retina, allowing also proper autophagy as a prerequisite for physiological cell fate and visual properties.
Collapse
Affiliation(s)
- Elisabetta Catalani
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Silvia Bongiorni
- Department of Ecological and Biological Sciences (DEB), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Anna Rita Taddei
- Section of Electron Microscopy, Great Equipment Center, Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Marta Mezzetti
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Federica Silvestri
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Marco Coazzoli
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy
| | - Silvia Zecchini
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy
| | - Matteo Giovarelli
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy
| | - Cristiana Perrotta
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy
| | - Clara De Palma
- Department of Medical Biotechnology and Translational Medicine (BioMeTra), Università degli Studi di Milano, via Luigi Vanvitelli 32, 20129 , Milano, Italy
| | - Emilio Clementi
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy
- Unit of Clinical Pharmacology, University Hospital "Luigi Sacco"-ASST Fatebenefratelli Sacco, via G.B. Grassi 74, 20157, Milano, Italy
- Scientific Institute IRCCS "Eugenio Medea", via Don Luigi Monza 20, 23842, Bosisio Parini (LC), Italy
| | - Marcello Ceci
- Department of Ecological and Biological Sciences (DEB), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Giorgio Prantera
- Department of Ecological and Biological Sciences (DEB), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy
| | - Davide Cervia
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), Università degli Studi della Tuscia, largo dell'Università snc, 01100, Viterbo, Italy.
- Department of Biomedical and Clinical Sciences "Luigi Sacco" (DIBIC), Università degli Studi di Milano, via G.B. Grassi 74, 20157, Milano, Italy.
| |
Collapse
|