1
|
Forró T, Manu DR, Băjenaru OL, Bălașa R. GFAP as Astrocyte-Derived Extracellular Vesicle Cargo in Acute Ischemic Stroke Patients-A Pilot Study. Int J Mol Sci 2024; 25:5726. [PMID: 38891912 PMCID: PMC11172178 DOI: 10.3390/ijms25115726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 05/18/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
The utility of serum glial fibrillary acidic protein (GFAP) in acute ischemic stroke (AIS) has been extensively studied in recent years. Here, we aimed to assess its potential role as a cargo protein of extracellular vesicles (EVs) secreted by astrocytes (ADEVs) in response to brain ischemia. Plasma samples from eighteen AIS patients at 24 h (D1), 7 days (D7), and one month (M1) post-symptoms onset, and nine age, sex, and cardiovascular risk factor-matched healthy controls were obtained to isolate EVs using the Exoquick ULTRA EV kit. Subsets of presumed ADEVs were identified further by the expression of the glutamate aspartate transporter (GLAST) as a specific marker of astrocytes with the Basic Exo-Flow Capture kit. Western blotting has tested the presence of GFAP in ADEV cargo. Post-stroke ADEV GFAP levels were elevated at D1 and D7 but not M1 compared to controls (p = 0.007, p = 0.019, and p = 0.344, respectively). Significant differences were highlighted in ADEV GFAP content at the three time points studied (n = 12, p = 0.027) and between D1 and M1 (z = 2.65, p = 0.023). A positive correlation was observed between the modified Rankin Scale (mRS) at D7 and ADEV GFAP at D1 (r = 0.58, p = 0.010) and D7 (r = 0.57, p = 0.013), respectively. ADEV GFAP may dynamically reflect changes during the first month post-ischemia. Profiling ADEVs from peripheral blood could provide a new way to assess the central nervous system pathology.
Collapse
Affiliation(s)
- Timea Forró
- Doctoral School of Medicine and Pharmacy, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540142 Targu Mures, Romania;
| | - Doina Ramona Manu
- Center for Advanced Medical and Pharmaceutical Research, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540142 Targu Mures, Romania
| | - Ovidiu-Lucian Băjenaru
- Discipline of Geriatrics and Gerontology, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania;
- National Institute of Gerontology and Geriatrics “Ana Aslan”, 11241 Bucharest, Romania
| | - Rodica Bălașa
- 1st Neurology Clinic, County Emergency Clinical Hospital of Targu Mures, 540136 Targu Mures, Romania;
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540142 Targu Mures, Romania
| |
Collapse
|
2
|
Yang AW, Lin NH, Yeh TH, Snider N, Perng MD. Effects of Alexander disease-associated mutations on the assembly and organization of GFAP intermediate filaments. Mol Biol Cell 2022; 33:ar69. [PMID: 35511821 PMCID: PMC9635275 DOI: 10.1091/mbc.e22-01-0013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Alexander disease is a primary genetic disorder of astrocytes caused by dominant mutations in the gene encoding glial fibrillary acidic protein (GFAP). How single-amino-acid changes can lead to cytoskeletal catastrophe and brain degeneration remains poorly understood. In this study, we have analyzed 14 missense mutations located in the GFAP rod domain to investigate how these mutations affect in vitro filament assembly. Whereas the internal rod mutants assembled into filaments that were shorter than those of wild type, the rod end mutants formed structures with one or more of several atypical characteristics, including short filament length, irregular width, roughness of filament surface, and filament aggregation. When transduced into primary astrocytes, GFAP mutants with in vitro assembly defects usually formed cytoplasmic aggregates, which were more resistant to biochemical extraction. The resistance of GFAP to solubilization was also observed in brain tissues of patients with Alexander disease, in which a significant proportion of insoluble GFAP were accumulated in Rosenthal fiber fractions. These findings provide clinically relevant evidence that link GFAP assembly defects to disease pathology at the tissue level and suggest that altered filament assembly and properties as a result of GFAP mutation are critical initiating factors for the pathogenesis of Alexander disease.
Collapse
Affiliation(s)
- Ai-Wen Yang
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Ni-Hsuan Lin
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Ting-Hung Yeh
- Department of Medical Science, College of Life Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Natasha Snider
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Ming-Der Perng
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu 30013, Taiwan,Department of Medical Science, College of Life Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan,*Address correspondence to: Ming-Der Perng ()
| |
Collapse
|
3
|
Lin NH, Yang AW, Chang CH, Perng MD. Elevated GFAP isoform expression promotes protein aggregation and compromises astrocyte function. FASEB J 2021; 35:e21614. [PMID: 33908669 DOI: 10.1096/fj.202100087r] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/19/2021] [Accepted: 04/06/2021] [Indexed: 01/22/2023]
Abstract
Alexander disease (AxD) caused by mutations in the coding region of GFAP is a neurodegenerative disease characterized by astrocyte dysfunction, GFAP aggregation, and Rosenthal fiber accumulation. Although how GFAP mutations cause disease is not fully understood, Rosenthal fibers could be induced by forced overexpression of human GFAP and this could be lethal in mice implicate that an increase in GFAP levels is central to AxD pathogenesis. Our recent studies demonstrated that intronic GFAP mutations cause disease by altering GFAP splicing, suggesting that an increase in GFAP isoform expression could lead to protein aggregation and astrocyte dysfunction that typify AxD. Here we test this hypothesis by establishing primary astrocyte cultures from transgenic mice overexpressing human GFAP. We found that GFAP-δ and GFAP-κ were disproportionately increased in transgenic astrocytes and both were enriched in Rosenthal fibers of human AxD brains. In vitro assembly studies showed that while the major isoform GFAP-α self-assembled into typical 10-nm filaments, minor isoforms including GFAP-δ, -κ, and -λ were assembly-compromised and aggregation prone. Lentiviral transduction showed that expression of these minor GFAP isoforms decreased filament solubility and increased GFAP stability, leading to the formation of Rosenthal fibers-like aggregates that also disrupted the endogenous intermediate filament networks. The aggregate-bearing astrocytes lost their normal morphology and glutamate buffering capacity, which had a toxic effect on neighboring neurons. In conclusion, our findings provide evidence that links elevated GFAP isoform expression with GFAP aggregation and impaired glutamate transport, and suggest a potential non-cell-autonomous mechanism underlying neurodegeneration through astrocyte dysfunction.
Collapse
Affiliation(s)
- Ni-Hsuan Lin
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
| | - Ai-Wen Yang
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Hsuan Chang
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
| | - Ming-Der Perng
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan
| |
Collapse
|
4
|
Fu MH, Chang YY, Lin NH, Yang AW, Chang CC, Liu JS, Peng CH, Wu KLH, Perng MD, Lan MY. Recessively-Inherited Adult-Onset Alexander Disease Caused by a Homozygous Mutation in the GFAP Gene. Mov Disord 2020; 35:1662-1667. [PMID: 32374915 DOI: 10.1002/mds.28099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/01/2020] [Accepted: 04/09/2020] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Alexander disease (AxD) is an autosomal-dominant leukodystrophy caused by heterozygous mutations in the glial fibrillary acidic protein (GFAP) gene. OBJECTIVES The objective of this report is to characterize the clinical phenotype and identify the genetic mutation associated with adult-onset AxD. METHODS A man presented with progressive unsteadiness since age 16. Magnetic resonance imaging findings revealed characteristic features of AxD. The GFAP gene was screened, and a candidate variant was functionally tested to evaluate causality. RESULTS A homozygous c.197G > A (p.Arg66Gln) mutation was found in the proband, and his asymptomatic parents were heterozygous for the same mutation. This mutation affected GFAP solubility and promoted filament aggregation. The presence of the wild-type protein rescued mutational effects, consistent with the recessive nature of this mutation. CONCLUSIONS This study is the first report of AxD caused by a homozygous mutation in GFAP. The clinical implication is while examining patients with characteristic features on suspicion of AxD, GFAP screening is recommended even without a supportive family history. © 2020 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Mu-Hui Fu
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Yung-Yee Chang
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Center for Parkinson's Disease, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Ni-Hsuan Lin
- Institute of Molecular Medicine, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Ai-Wen Yang
- Institute of Molecular Medicine, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Chiung-Chih Chang
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jia-Shou Liu
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Cheng-Huei Peng
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.,Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan, Taiwan
| | - Ming-Der Perng
- Institute of Molecular Medicine, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, College of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Min-Yu Lan
- Department of Neurology, Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Center for Parkinson's Disease, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| |
Collapse
|
5
|
Jonesco DS, Hassager C, Frydland M, Kjærgaard J, Karsdal M, Henriksen K. A caspase-6-cleaved fragment of Glial Fibrillary Acidic Protein as a potential serological biomarker of CNS injury after cardiac arrest. PLoS One 2019; 14:e0224633. [PMID: 31693684 PMCID: PMC6834260 DOI: 10.1371/journal.pone.0224633] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/17/2019] [Indexed: 12/31/2022] Open
Abstract
Blood levels of Glial Fibrillary Acidic protein (GFAP) reflect processes associated with different types of CNS injury. Evidence suggests that GFAP is cleaved by caspases during CNS injury, hence positioning GFAP fragments as potential biomarkers of injury-associated processes. We set out to develop an assay detecting the neo-epitope generated by caspase-6 cleavage of GFAP (GFAP-C6), and to assess the ability of GFAP-C6 to reflect pathological processes in patients suffering a cardiac arrest and subsequent global cerebral ischemia. Anti-GFAP-C6 antibodies recognized their specific target sequence, and dilution and spike recoveries in serum were within limits of ±20% reflecting high precision and accuracy of measurements. Intra- and inter-assay CVs were below limits of 10% and 15%, respectively. Serological levels of GFAP-C6 were significantly elevated 72 hours after CA (Mean±SD) (20.39±10.59 ng/mL) compared to time of admission (17.79±10.77 ng/mL, p<0.0001), 24 hours (17.40±7.99 ng/mL, p<0.0001) and 48 hours (17.87±8.56 ng/mL, p<0.0001) after CA, but were not related to neurological outcome at day 180. GFAP-C6 levels at admission, 24, 48, and 72 hours after cardiac arrest correlated with two proteolytic fragments of tau, tau-A (r = 0.30, r = 0.40, r = 0.50, r = 0.53, p < 0.0001) and tau-C (r = 54, r = 0.48, r = 0.55, r = 0.54, p < 0.0001), respectively. GFAP-C6 levels did not correlate with other markers of CNS damage; total tau, NSE and S100B. In conclusion, we developed the first assay detecting a caspase-6 cleaved fragment of GFAP in blood. Increased levels at 72 hours after cardiac arrest as well as moderate correlations between GFAP-C6 and two other blood biomarkers of neurodegeneration suggest the ability of GFAP-C6 to reflect pathological processes of the injured brain. Investigations into the potential of GFAP-C6 in other types of CNS injury are warranted.
Collapse
Affiliation(s)
- Ditte S. Jonesco
- Biomarkers & Research, Nordic Bioscience, Herlev, Denmark
- * E-mail:
| | - Christian Hassager
- Department of Cardiology B, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Martin Frydland
- Department of Cardiology B, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Jesper Kjærgaard
- Department of Cardiology B, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Morten Karsdal
- Biomarkers & Research, Nordic Bioscience, Herlev, Denmark
| | - Kim Henriksen
- Biomarkers & Research, Nordic Bioscience, Herlev, Denmark
| |
Collapse
|
6
|
Falcone C, Wolf-Ochoa M, Amina S, Hong T, Vakilzadeh G, Hopkins WD, Hof PR, Sherwood CC, Manger PR, Noctor SC, Martínez-Cerdeño V. Cortical interlaminar astrocytes across the therian mammal radiation. J Comp Neurol 2019; 527:1654-1674. [PMID: 30552685 DOI: 10.1002/cne.24605] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 01/21/2023]
Abstract
Interlaminar astrocytes (ILA) in the cerebral cortex possess a soma in layer I and extend an interlaminar process that runs perpendicular to the pia into deeper cortical layers. We examined cerebral cortex from 46 species that encompassed most orders of therian mammalians, including 22 primate species. We described two distinct cell types with interlaminar processes that have been referred to as ILA, that we termed pial ILA and supial ILA. ILA subtypes differ in somatic morphology, position in layer I, and presence across species. We further described rudimentary ILA that have short GFAP+ processes that do not exit layer I, and "typical" ILA with longer GFAP+ processes that exit layer I. Pial ILA were present in all mammalian species analyzed, with typical ILA observed in Primates, Scandentia, Chiroptera, Carnivora, Artiodactyla, Hyracoidea, and Proboscidea. Subpial ILA were absent in Marsupialia, and typical subpial ILA were only found in Primate. We focused on the properties of pial ILA by investigating the molecular properties of pial ILA and confirming their astrocytic nature. We found that while the density of pial ILA somata only varied slightly, the complexity of ILA processes varied greatly across species. Primates, specifically bonobo, chimpanzee, orangutan, and human, exhibited pial ILA with the highest complexity. We showed that interlaminar processes contact neurons, pia, and capillaries, suggesting a potential role for ILA in the blood-brain barrier and facilitating communication among cortical neurons, astrocytes, capillaries, meninges, and cerebrospinal fluid.
Collapse
Affiliation(s)
- Carmen Falcone
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, California.,Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California
| | - Marisol Wolf-Ochoa
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, California.,Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California
| | - Sarwat Amina
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California.,UC Davis Medical Center, MIND Institute, Sacramento, California
| | - Tiffany Hong
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, California.,Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California
| | - Gelareh Vakilzadeh
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, California.,Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California
| | - William D Hopkins
- Neuroscience Institute and Language Research Center, Georgia State University, Atlanta, Georgia
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC
| | - Paul R Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Stephen C Noctor
- UC Davis Medical Center, MIND Institute, Sacramento, California.,Department of Psychiatry and Behavioral Sciences, UC Davis School of Medicine, Sacramento, California
| | - Verónica Martínez-Cerdeño
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, California.,Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, Sacramento, California.,UC Davis Medical Center, MIND Institute, Sacramento, California
| |
Collapse
|
7
|
van Bodegraven EJ, van Asperen JV, Robe PAJ, Hol EM. Importance of GFAP isoform-specific analyses in astrocytoma. Glia 2019; 67:1417-1433. [PMID: 30667110 PMCID: PMC6617972 DOI: 10.1002/glia.23594] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/28/2018] [Accepted: 01/03/2019] [Indexed: 12/12/2022]
Abstract
Gliomas are a heterogenous group of malignant primary brain tumors that arise from glia cells or their progenitors and rely on accurate diagnosis for prognosis and treatment strategies. Although recent developments in the molecular biology of glioma have improved diagnosis, classical histological methods and biomarkers are still being used. The glial fibrillary acidic protein (GFAP) is a classical marker of astrocytoma, both in clinical and experimental settings. GFAP is used to determine glial differentiation, which is associated with a less malignant tumor. However, since GFAP is not only expressed by mature astrocytes but also by radial glia during development and neural stem cells in the adult brain, we hypothesized that GFAP expression in astrocytoma might not be a direct indication of glial differentiation and a less malignant phenotype. Therefore, we here review all existing literature from 1972 up to 2018 on GFAP expression in astrocytoma patient material to revisit GFAP as a marker of lower grade, more differentiated astrocytoma. We conclude that GFAP is heterogeneously expressed in astrocytoma, which most likely masks a consistent correlation of GFAP expression to astrocytoma malignancy grade. The GFAP positive cell population contains cells with differences in morphology, function, and differentiation state showing that GFAP is not merely a marker of less malignant and more differentiated astrocytoma. We suggest that discriminating between the GFAP isoforms GFAPδ and GFAPα will improve the accuracy of assessing the differentiation state of astrocytoma in clinical and experimental settings and will benefit glioma classification.
Collapse
Affiliation(s)
- Emma J van Bodegraven
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Jessy V van Asperen
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Pierre A J Robe
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.,Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105, BA, Amsterdam, The Netherlands
| |
Collapse
|
8
|
Carvalho-Paulo D, de Morais Magalhães NG, de Almeida Miranda D, Diniz DG, Henrique EP, Moraes IAM, Pereira PDC, de Melo MAD, de Lima CM, de Oliveira MA, Guerreiro-Diniz C, Sherry DF, Diniz CWP. Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla. Front Neuroanat 2018; 11:126. [PMID: 29354035 PMCID: PMC5758497 DOI: 10.3389/fnana.2017.00126] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/05/2017] [Indexed: 01/09/2023] Open
Abstract
Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla, that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D) morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy (n = 249 cells) with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period (n = 250 cells). Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes may play different physiological roles during migration.
Collapse
Affiliation(s)
- Dario Carvalho-Paulo
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Nara G de Morais Magalhães
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Diego de Almeida Miranda
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Daniel G Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Ediely P Henrique
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Isis A M Moraes
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Patrick D C Pereira
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Mauro A D de Melo
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Camila M de Lima
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Marcus A de Oliveira
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Cristovam Guerreiro-Diniz
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - David F Sherry
- Department of Psychology, University of Western Ontario, London, ON, Canada.,Advanced Facility for Avian Research, University of Western Ontario, London, ON, Canada
| | - Cristovam W P Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| |
Collapse
|