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Expression of Heat Shock Protein 70 Is Insufficient To Extend Drosophila melanogaster Longevity. G3-GENES GENOMES GENETICS 2019; 9:4197-4207. [PMID: 31624139 PMCID: PMC6893204 DOI: 10.1534/g3.119.400782] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It has been known for over 20 years that Drosophila melanogaster flies with twelve additional copies of the hsp70 gene encoding the 70 kD heat shock protein lives longer after a non-lethal heat treatment. Since the heat treatment also induces the expression of additional heat shock proteins, the biological effect can be due either to HSP70 acting alone or in combination. This study used the UAS/GAL4 system to determine whether hsp70 is sufficient to affect the longevity and the resistance to thermal, oxidative or desiccation stresses of the whole organism. We observed that HSP70 expression in the nervous system or muscles has no effect on longevity or stress resistance but ubiquitous expression reduces the life span of males. We also observed that the down-regulation of hsp70 using RNAi did not affect longevity.
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Matsumura T, Matsumoto H, Hayakawa Y. Heat stress hardening of oriental armyworms is induced by a transient elevation of reactive oxygen species during sublethal stress. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2017; 96:e21421. [PMID: 28872705 DOI: 10.1002/arch.21421] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Pre-exposure to mild heat stress enhances the thermotolerance of insects. Stress hardening is a beneficial physiological plasticity, but the mechanism underlying it remains elusive. Here we report that reactive oxygen species (ROS) concentrations were quickly and transiently elevated in the armyworms, Mythimna separata, by exposing them to 40°C, but not other tested temperatures. Larvae exposed to 40°C had subsequently elevated antioxidant activity and the highest survival of all tested heating conditions. The elevation of ROS after lethal heating at 44°C for 1 h was approximately twofold compared to heating at 40°C. Injection of an optimal amount of hydrogen peroxide (H2 O2 ) similarly caused sequential elevation of ROS and antioxidant activity in the test larval hemolymph, which led to significantly enhanced survival after lethal heat stress. The H2 O2 -induced thermotolerance was abolished by coinjection of potent antioxidants such as ascorbic acid or N-acetylcysteine. Both preheating at 40°C and H2 O2 injection enhanced expression of genes encoding superoxide dismutase 1, catalase, and heat shock protein 70 in the fat body of test larvae, indicating the adequate heat stress induced a transient elevation of ROS, followed by upregulation of antioxidant activity. We infer that thermal stress hardening is induced by a small timely ROS elevation that triggers a reduction-oxidation signaling mechanism.
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Affiliation(s)
- Takashi Matsumura
- Department of Applied Biological Sciences, Saga University, Saga, Japan
| | - Hitoshi Matsumoto
- Department of Applied Biological Sciences, Saga University, Saga, Japan
| | - Yoichi Hayakawa
- Department of Applied Biological Sciences, Saga University, Saga, Japan
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Basic mechanisms of longevity: A case study of Drosophila pro-longevity genes. Ageing Res Rev 2015; 24:218-31. [PMID: 26318059 DOI: 10.1016/j.arr.2015.08.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 08/11/2015] [Accepted: 08/20/2015] [Indexed: 12/13/2022]
Abstract
Drosophila is one of the most convenient model organisms in the genetics of aging and longevity. Unlike the nematodes, which allow for the detection of new pro-aging genes by knockout and RNAi-mediated knock-down, Drosophila also provides an opportunity to find new pro-longevity genes by driver-induced overexpression. Similar studies on other models are extremely rare. In this review, we focused on genes whose overexpression prolongs the life of fruit flies. The majority of longevity-associated genes regulates metabolism and stress resistance, and belongs to the IGF-1R, PI3K, PKB, AMPK and TOR metabolic regulation cluster and the FOXO, HDAC, p53 stress response cluster.
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Le Bourg É. Fasting and other mild stresses with hormetic effects in Drosophila melanogaster can additively increase resistance to cold. Biogerontology 2015; 16:517-27. [DOI: 10.1007/s10522-015-9574-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 04/06/2015] [Indexed: 11/29/2022]
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Halle S, Nowizki A, Scharf I. The consequences of parental age for development, body mass and resistance to stress in the red flour beetle. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Snir Halle
- Department of Zoology; Faculty of Life Sciences; Tel Aviv University; POB 39040 Tel Aviv 6997801 Israel
| | - Anastasia Nowizki
- Department of Zoology; Faculty of Life Sciences; Tel Aviv University; POB 39040 Tel Aviv 6997801 Israel
| | - Inon Scharf
- Department of Zoology; Faculty of Life Sciences; Tel Aviv University; POB 39040 Tel Aviv 6997801 Israel
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Wit J, Kristensen TN, Sarup P, Frydenberg J, Loeschcke V. Laboratory selection for increased longevity in Drosophila melanogaster reduces field performance. Exp Gerontol 2013; 48:1189-95. [DOI: 10.1016/j.exger.2013.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/19/2013] [Accepted: 07/25/2013] [Indexed: 10/26/2022]
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Le Bourg É. Fasting can protect young and middle-aged Drosophila melanogaster flies against a severe cold stress. Biogerontology 2013; 14:513-29. [PMID: 23990216 DOI: 10.1007/s10522-013-9458-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 08/24/2013] [Indexed: 01/10/2023]
Abstract
Flies were starved with water before being subjected to various severe stresses (heat, cold, fungal infection, hydrogen peroxide) immediately after starvation or after a delay. Starvation of young and middle-aged flies increased resistance to a long cold stress (0 °C for up to 48 h), mainly if there was a 2-6 h delay between starvation and the cold stress, but positive effects in old flies were hardly observed. No positive effect was observed on resistance to the other stresses and starvation rather decreased resistance to them. It thus seems that fasting increases frailty but also puts at play mechanisms increasing resistance to cold. Starvation also increased learning scores but this could be linked to decreased positive phototaxis tendencies, and not to a better learning ability. Starvation appears to be a mild stress with limited hormetic effects, but studying the mechanisms of these effects is of interest because fasting is maybe of therapeutic value in human beings.
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Affiliation(s)
- Éric Le Bourg
- Centre de Recherches sur la Cognition Animale, UMR CNRS 5169 Université Paul-Sabatier, 31062, Toulouse 9, France,
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Lazarević J, Đorđević M, Stojković B, Tucić N. Resistance to prooxidant agent paraquat in the short- and long-lived lines of the seed beetle (Acanthoscelides obtectus). Biogerontology 2013; 14:141-52. [DOI: 10.1007/s10522-013-9417-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 03/04/2013] [Indexed: 01/25/2023]
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Pickering AM, Vojtovich L, Tower J, Davies KJA. Oxidative stress adaptation with acute, chronic, and repeated stress. Free Radic Biol Med 2013; 55:109-18. [PMID: 23142766 PMCID: PMC3687790 DOI: 10.1016/j.freeradbiomed.2012.11.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 10/07/2012] [Accepted: 11/02/2012] [Indexed: 12/15/2022]
Abstract
Oxidative stress adaptation, or hormesis, is an important mechanism by which cells and organisms respond to, and cope with, environmental and physiological shifts in the level of oxidative stress. Most studies of oxidative stress adaption have been limited to adaptation induced by acute stress. In contrast, many if not most environmental and physiological stresses are either repeated or chronic. In this study we find that both cultured mammalian cells and the fruit fly Drosophila melanogaster are capable of adapting to chronic or repeated stress by upregulating protective systems, such as their proteasomal proteolytic capacity to remove oxidized proteins. Repeated stress adaptation resulted in significant extension of adaptive responses. Repeated stresses must occur at sufficiently long intervals, however (12-h or more for MEF cells and 7 days or more for flies), for adaptation to be successful, and the levels of both repeated and chronic stress must be lower than is optimal for adaptation to acute stress. Regrettably, regimens of adaptation to both repeated and chronic stress that were successful for short-term survival in Drosophila nevertheless also caused significant reductions in life span for the flies. Thus, although both repeated and chronic stress can be tolerated, they may result in a shorter life.
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Affiliation(s)
- Andrew M. Pickering
- Ethel Percy Andrus Gerontology Center of the Davis School of Gerontology, The University of Southern California, Los Angeles, CA 90089, USA
- Molecular and Computational Biology Program, Department of Biological Sciences, Dornsife College of Letters, Arts & Sciences; The University of Southern California, Los Angeles, CA 90089, USA
| | - Lesya Vojtovich
- Ethel Percy Andrus Gerontology Center of the Davis School of Gerontology, The University of Southern California, Los Angeles, CA 90089, USA
| | - John Tower
- Molecular and Computational Biology Program, Department of Biological Sciences, Dornsife College of Letters, Arts & Sciences; The University of Southern California, Los Angeles, CA 90089, USA
| | - Kelvin J. A. Davies
- Ethel Percy Andrus Gerontology Center of the Davis School of Gerontology, The University of Southern California, Los Angeles, CA 90089, USA
- Molecular and Computational Biology Program, Department of Biological Sciences, Dornsife College of Letters, Arts & Sciences; The University of Southern California, Los Angeles, CA 90089, USA
- Senior author to whom correspondence should be addressed as follows: Prof. Kelvin J. A. Davies, Ethel Percy Andrus Gerontology Center, the University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, U.S.A., Telephone: (213)740-8959, Fax number: (213)740-6462,
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Le Bourg É. Combined effects of two mild stresses (cold and hypergravity) on longevity, behavioral aging, and resistance to severe stresses in Drosophila melanogaster. Biogerontology 2012; 13:313-28. [DOI: 10.1007/s10522-012-9377-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 02/20/2012] [Indexed: 11/28/2022]
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11
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Le Bourg É. Using Drosophila melanogaster to study the positive effects of mild stress on aging. Exp Gerontol 2011; 46:345-8. [DOI: 10.1016/j.exger.2010.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 07/08/2010] [Accepted: 08/06/2010] [Indexed: 11/16/2022]
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Morrow G, Kim HJ, Le Pécheur M, Kaul SC, Wadhwa R, Tanguay RM. Protection from aging by small chaperones: A trade-off with cancer? Ann N Y Acad Sci 2010; 1197:67-75. [PMID: 20536835 DOI: 10.1111/j.1749-6632.2009.05413.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Aging is a complex process accompanied by a decreased capacity of cells to cope with random molecular damages. Damaged proteins can form aggregates and have cytotoxic properties, a feature of many age-associated diseases. Small Hsps are chaperones involved in the refolding and/or disposal of protein aggregates. In Drosophila melanogaster, the mitochondrial DmHsp22 is preferentially upregulated during aging. Its over-expression results in an extension of lifespan (>30%) and an increased resistance to stress. Although DmHsp22 has a chaperone-like activity in vitro, additional mechanisms by which it may extend lifespan in vivo are unknown. Genome-wide transcriptional analysis and comparative mitochondrial proteomic analysis by MALDI-TOF were performed to unveil differences in long-lived DmHsp22 over-expressing flies. Flies over-expressing DmHsp22 display an upregulation of genes normally downregulated with age and involved in energy production and protein biosynthesis. Interestingly, DmHsp22 over-expression extended lifespan of normal fibroblasts by slowing the aging process. However, its expression also increased the malignant properties of human transformed cells. The delicate balance between beneficial and noxious effects of this small chaperone are discussed.
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Affiliation(s)
- Geneviève Morrow
- Laboratory of Cell and Developmental Genetics, Department of Molecular Biology, Medical Biochemistry and Pathology, Institut de Biologie Intégrative et des Systèmes and PROTEO Université Laval, Québec, Canada
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13
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Hormesis, aging and longevity. Biochim Biophys Acta Gen Subj 2009; 1790:1030-9. [DOI: 10.1016/j.bbagen.2009.01.004] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 01/14/2009] [Accepted: 01/15/2009] [Indexed: 12/31/2022]
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14
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Vanhooren V, Liu XE, Desmyter L, Fan YD, Vanwalleghem L, Van Molle W, Dewaele S, Praet M, Contreras R, Libert C, Chen C. Over-expression of heat shock protein 70 in mice is associated with growth retardation, tumor formation, and early death. Rejuvenation Res 2009; 11:1013-20. [PMID: 19072255 DOI: 10.1089/rej.2008.0783] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Experiments in lower organisms, such as worms and flies, indicate that the molecular chaperone protein heat shock protein 70 (HSP70) is a longevity factor. In contrast, we demonstrate here that mice overexpressing HSP70 display growth retardation and early death. HSP70 transgenic mice displayed increased levels of serum corticosterone and weaker expression and activity of the glucocorticoid receptor in the liver. Serum insulin-like growth factor-1 (IGF-1) concentrations in the transgenic mice were 50% lower than in the control mice, leading to growth retardation. HSP70 transgenic mice showed decreased expression of Casp9, which encodes caspase-9, and increased expression of the anti-apoptotic Bcl-2 gene, indicating that apoptosis is suppressed. Consequently, most of the transgenic animals died before the age of 18 months from tumors in their lungs and lymph nodes. We suggest that the proinflammatory and antiapoptotic effects of HSP70 might be responsible for the growth retardation, tumor formation, and early death observed in the HSP70 transgenic mice.
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Bowler K, Terblanche JS. Insect thermal tolerance: what is the role of ontogeny, ageing and senescence? Biol Rev Camb Philos Soc 2008; 83:339-55. [PMID: 18979595 DOI: 10.1111/j.1469-185x.2008.00046.x] [Citation(s) in RCA: 306] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Temperature has dramatic evolutionary fitness consequences and is therefore a major factor determining the geographic distribution and abundance of ectotherms. However, the role that age might have on insect thermal tolerance is often overlooked in studies of behaviour, ecology, physiology and evolutionary biology. Here, we review the evidence for ontogenetic and ageing effects on traits of high- and low-temperature tolerance in insects and show that these effects are typically pronounced for most taxa in which data are available. We therefore argue that basal thermal tolerance and acclimation responses (i.e. phenotypic plasticity) are strongly influenced by age and/or ontogeny and may confound studies of temperature responses if unaccounted for. We outline three alternative hypotheses which can be distinguished to propose why development affects thermal tolerance in insects. At present no studies have been undertaken to directly address these options. The implications of these age-related changes in thermal biology are discussed and, most significantly, suggest that the temperature tolerance of insects should be defined within the age-demographics of a particular population or species. Although we conclude that age is a source of variation that should be carefully controlled for in thermal biology, we also suggest that it can be used as a valuable tool for testing evolutionary theories of ageing and the cellular and genetic basis of thermal tolerance.
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Affiliation(s)
- Ken Bowler
- Department of Biological and Biomedical Sciences, University of Durham, Durham City, DH1 3LE, UK
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16
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Abstract
Most animals face periods of food shortage and are thus expected to evolve adaptations enhancing starvation resistance (SR). Most of our knowledge of the genetic and physiological bases of those adaptations, their evolutionary correlates and trade-offs, and patterns of within- and among-population variation, comes from studies on Drosophila. In this review, we attempt to synthesize the various facets of evolutionary biology of SR emerging from those studies. Heritable variation for SR is ubiquitous in Drosophila populations, allowing for large responses to experimental selection. Individual flies can also inducibly increase their SR in response to mild nutritional stress (dietary restriction). Both the evolutionary change and the physiological plasticity involve increased accumulation of lipids, changes in carbohydrate and lipid metabolism and reduction in reproduction. They are also typically associated with greater resistance to desiccation and oxidative stress, and with prolonged development and lifespan. These responses are increasingly seen as facets of a shift of the physiology towards a 'survival mode', which helps the animal to survive hard times. The last decade has seen a great progress in revealing the molecular bases of induced responses to starvation, and the first genes contributing to genetic variation in SR have been identified. In contrast, little progress has been made in understanding the ecological significance of SR in Drosophila; in particular it remains unclear to what extent geographical variation in SR reflect differences in natural selection acting on this trait rather than correlated responses to selection on other traits. Drosophila offers a unique opportunity for an integrated study of the manifold aspects of adaptation to nutritional stress. Given that at least some major molecular mechanisms of response to nutritional stress seem common to animals, the insights from Drosophila are likely to apply more generally than just to dipterans or insects.
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Affiliation(s)
- S Rion
- Section of Ecology and Evolution, Department of Biology, University of Fribourg, Fribourg, Switzerland
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Burger JMS, Hwangbo DS, Corby-Harris V, Promislow DEL. The functional costs and benefits of dietary restriction in Drosophila. Aging Cell 2007; 6:63-71. [PMID: 17266676 DOI: 10.1111/j.1474-9726.2006.00261.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Dietary restriction (DR) extends lifespan in an impressively wide array of species spanning three eukaryotic kingdoms. In sharp contrast, relatively little is known about the effects of DR on functional senescence, with most of the work having been done on mice and rats. Here we used Drosophila melanogaster to test the assumption that lifespan extension through DR slows down age-related functional deterioration. Adult virgin females were kept on one of three diets, with sucrose and yeast concentrations ranging from 7% to 11% to 16% (w/v). Besides age-specific survival and fecundity, we measured starvation resistance, oxidative stress resistance, immunity, and cold-stress resilience at ages 1, 3, 5, and 7 weeks. We confirmed that DR extends lifespan: median lifespans ranged from 38 days (16% diet) to 46 days (11% diet) to 54 days (7% diet). We also confirmed that DR reduces fecundity, although the shortest-lived flies only had the highest fecundity when males were infrequently available. The most striking result was that DR initially increased starvation resistance, but strongly decreased starvation resistance later in life. Generally, the effects of DR varied across traits and were age dependent. We conclude that DR does not universally slow down functional deterioration in Drosophila. The effects of DR on physiological function might not be as evolutionarily conserved as its effect on lifespan. Given the age-specific effects of DR on functional state, imposing DR late in life might not provide the same functional benefits as when applied at early ages.
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Affiliation(s)
- Joep M S Burger
- Department of Genetics, University of Georgia, Life Sciences Building, Athens, GA 30602-7223, USA.
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Burger JMS, Promislow DEL. Are functional and demographic senescence genetically independent? Exp Gerontol 2006; 41:1108-16. [PMID: 17045439 DOI: 10.1016/j.exger.2006.08.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 08/11/2006] [Accepted: 08/22/2006] [Indexed: 11/19/2022]
Abstract
Biogerontology has traditionally focused on demographic senescence by searching for environmental manipulations and genes that extend life span. Relatively little is known about age-specific changes in functional traits and how demographic and functional senescence are genetically (co)regulated. To determine whether functional and demographic senescence have a similar genetic basis, we measured genotypic variation in the age-related change in cold-stress resilience and age-specific mortality using ten inbred lines of Drosophila melanogaster. Cold-stress resilience was measured as the average time for a population of flies to recover from a chill coma after being placed on melting ice for 6 h. We found genotypic variation in both sexes for chill-coma resilience, for the rate at which it declines with age, for longevity, for the initial mortality rate, and for the rate at which mortality increases with age. However, there was no genotypic correlation between any of these functional and demographic parameters. These results suggest that deterioration of at least some functional traits might be genetically independent of mortality patterns. Models for the genetic basis of senescence may do well to distinguish between quality and quantity of life in terms of their genetic architectures, and the way selection acts upon these two age-related factors.
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Affiliation(s)
- Joep M S Burger
- Department of Genetics, University of Georgia, Life Sciences Building, Athens, GA 30602, USA.
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Abstract
Alpha-synuclein is likely to play a role in neurodegenerative processes, including the degeneration of nigrostriatal dopaminergic neurons that underlies Parkinson's disease. However, the toxicological properties of alpha-synuclein remain relatively unknown. Here, the relationship between alpha-synuclein expression and neuronal injury was studied in mice exposed to the herbicide paraquat. Paraquat neurotoxicity was compared in control animals versus mice with transgenic expression of human alpha-synuclein driven by the tyrosine hydroxylase (TH) promoter. In control mice, paraquat caused both the formation of alpha-synuclein-containing intraneuronal deposits and the degeneration of nigrostriatal neurons, as demonstrated by silver staining and a reduction of the counts of TH-positive and Nissl-stained cells. Mice overexpressing alpha-synuclein, either the human wild-type or the Ala53Thr mutant form of the protein, displayed paraquat-induced protein aggregates but were completely protected against neurodegeneration. These resistant animals were also characterized by increased levels of HSP70, a chaperone protein that has been shown to counteract paraquat toxicity in other experimental models and could therefore contribute to neuroprotection in alpha-synuclein transgenic mice. The results indicate a dissociation between toxicant-induced alpha-synuclein deposition and neurodegeneration. They support a role of alpha-synuclein against toxic insults and suggest that its involvement in human neurodegenerative processes may arise not only from a gain of toxic function, as previously proposed, but also from a loss of defensive properties.
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