1
|
Álvarez-Hernán G, de Mera-Rodríguez JA, Hernández-Núñez I, Marzal A, Gañán Y, Martín-Partido G, Rodríguez-León J, Francisco-Morcillo J. Analysis of Programmed Cell Death and Senescence Markers in the Developing Retina of an Altricial Bird Species. Cells 2021; 10:cells10030504. [PMID: 33652964 PMCID: PMC7996935 DOI: 10.3390/cells10030504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/19/2021] [Accepted: 02/23/2021] [Indexed: 12/30/2022] Open
Abstract
This study shows the distribution patterns of apoptotic cells and biomarkers of cellular senescence during the ontogeny of the retina in the zebra finch (T. guttata). Neurogenesis in this altricial bird species is intense in the retina at perinatal and post-hatching stages, as opposed to precocial bird species in which retinogenesis occurs entirely during the embryonic period. Various phases of programmed cell death (PCD) were distinguishable in the T. guttata visual system. These included areas of PCD in the central region of the neuroretina at the stages of optic cup morphogenesis, and in the sub-optic necrotic centers (St15–St20). A small focus of early neural PCD was detected in the neuroblastic layer, dorsal to the optic nerve head, coinciding with the appearance of the first differentiated neuroblasts (St24–St25). There were sparse pyknotic bodies in the non-laminated retina between St26 and St37. An intense wave of neurotrophic PCD was detected in the laminated retina between St42 and P8, the last post-hatching stage included in the present study. PCD was absent from the photoreceptor layer. Phagocytic activity was also detected in Müller cells during the wave of neurotrophic PCD. With regard to the chronotopographical staining patterns of senescence biomarkers, there was strong parallelism between the SA-β-GAL signal and p21 immunoreactivity in both the undifferentiated and the laminated retina, coinciding in the cell body of differentiated neurons. In contrast, no correlation was found between SA-β-GAL activity and the distribution of TUNEL-positive cells in the developing tissue.
Collapse
Affiliation(s)
- Guadalupe Álvarez-Hernán
- Área de Biología Celular Departamento de Anatomía Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; (G.Á.-H.); (J.A.d.M.-R.); (I.H.-N.); (G.M.-P.)
| | - José Antonio de Mera-Rodríguez
- Área de Biología Celular Departamento de Anatomía Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; (G.Á.-H.); (J.A.d.M.-R.); (I.H.-N.); (G.M.-P.)
| | - Ismael Hernández-Núñez
- Área de Biología Celular Departamento de Anatomía Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; (G.Á.-H.); (J.A.d.M.-R.); (I.H.-N.); (G.M.-P.)
| | - Alfonso Marzal
- Área de Zoología, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain;
| | - Yolanda Gañán
- Área de Anatomía y Embriología Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, 06006 Badajoz, Spain;
| | - Gervasio Martín-Partido
- Área de Biología Celular Departamento de Anatomía Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; (G.Á.-H.); (J.A.d.M.-R.); (I.H.-N.); (G.M.-P.)
| | - Joaquín Rodríguez-León
- Área de Anatomía y Embriología Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, 06006 Badajoz, Spain;
- Correspondence: (J.R.-L.); (J.F.-M.)
| | - Javier Francisco-Morcillo
- Área de Biología Celular Departamento de Anatomía Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; (G.Á.-H.); (J.A.d.M.-R.); (I.H.-N.); (G.M.-P.)
- Correspondence: (J.R.-L.); (J.F.-M.)
| |
Collapse
|
2
|
de Mera-Rodríguez JA, Álvarez-Hernán G, Gañán Y, Martín-Partido G, Rodríguez-León J, Francisco-Morcillo J. Senescence-associated β-galactosidase activity in the developing avian retina. Dev Dyn 2019; 248:850-865. [PMID: 31226225 DOI: 10.1002/dvdy.74] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/22/2019] [Accepted: 06/15/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Senescence-associated β-galactosidase (SA-β-GAL) histochemistry is the most commonly used biomarker of cellular senescence. These SA-β-GAL-positive cells are senescent embryonic cells that are usually removed by apoptosis from the embryo, followed by macrophage-mediated clearance. RESULTS Some authors have proposed that SA-β-GAL activity in differentiated neurons from young and adult mammals cannot be uniquely attributed to cell senescence, whether in vivo or in vitro. Using the developing visual system of the chicken as a model, the present study found that SA-β-GAL detected in the developing retina corresponded to lysosomal β-galactosidase activity, and that SA-β-GAL activity did not correlate with the chronotopographical distribution of apoptotic cells. However, SA-β-GAL staining in the undifferentiated retina coincided with the appearance of early differentiating neurons. In the laminated retina, SA-β-GAL staining was concentrated in the ganglion, amacrine, and horizontal cell layers. The photoreceptors and pigment epithelial cells also exhibited SA-β-GAL activity throughout retinal development. We have also found that SA-β-GAL staining strongly correlated p21 immunoreactivity. CONCLUSION In conclusion, the results clearly show that SA-β-GAL activity cannot be regarded as a specific marker of senescence during retinal development, and that it is mainly expressed in subpopulations of postmitotic neurons, which are nonproliferative cells, even at early stages of cell differentiation.
Collapse
Affiliation(s)
- José Antonio de Mera-Rodríguez
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Guadalupe Álvarez-Hernán
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Yolanda Gañán
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Gervasio Martín-Partido
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Joaquín Rodríguez-León
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Javier Francisco-Morcillo
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| |
Collapse
|
3
|
Bejarano-Escobar R, Sánchez-Calderón H, Otero-Arenas J, Martín-Partido G, Francisco-Morcillo J. Müller glia and phagocytosis of cell debris in retinal tissue. J Anat 2017; 231:471-483. [PMID: 28695619 DOI: 10.1111/joa.12653] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/10/2017] [Indexed: 12/19/2022] Open
Abstract
Müller cells are the predominant glial cell type in the retina of vertebrates. They play a wide variety of roles in both the developing and the mature retina that have been widely reported in the literature. However, less attention has been paid to their role in phagocytosis of cell debris under physiological, pathological or experimental conditions. Müller glia have been shown to phagocytose apoptotic cell bodies originated during development of the visual system. They also engulf foreign molecules that are injected into the eye, cone outer segments and injured photoreceptors. Phagocytosis of photoreceptor cell debris in the light-damaged teleost retina is primarily carried out by Müller cells. Once the microglial cells become activated and migrate to the photoreceptor cell layer, the phagocytic activity of Müller cells progressively decreases, suggesting a possible mechanism of communication between Müller cells and neighbouring microglia and photoreceptors. Additionally, it has been shown that phagocytic Müller cells acquire proliferating activity in the damaged teleost retina, suggesting that engulfment of apoptotic photoreceptor debris might stimulate the Müller glia to proliferate during the regenerative response. These findings highlight Müller glia phagocytosis as an underlying mechanism contributing to degeneration and regeneration under pathological conditions.
Collapse
Affiliation(s)
- Ruth Bejarano-Escobar
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | | | - Josué Otero-Arenas
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Gervasio Martín-Partido
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | | |
Collapse
|
4
|
Pinelli C, Sansone A, De Maio A, Morgillo A, Scandurra A, D'Aniello B. Proliferative events and apoptotic remodelling in retinal development of common toad (Bufo bufo). JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2015; 326:19-30. [PMID: 26541902 DOI: 10.1002/jez.b.22661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/22/2015] [Indexed: 12/22/2022]
Abstract
Proliferation and apoptosis are fundamental processes in the development of the retina, and a proper balance of the two phenomena is crucial to correct development of the organ. Despite intense investigation in different vertebrates, only a few studies have analyzed the cell death and the cell division quantitatively in the same species during development. Here we studied the time course of apoptosis and proliferation in the retina of common toad, Bufo bufo, and discuss the findings in an evolutionary perspective. We found cells that were dividing first scattered throughout the retina, then, in later stages, proliferation was confined to the ciliary marginal zone. This pattern was confirmed by the expression of the proliferative marker PCNA. Both proliferation and apoptosis occurred in successive waves, and two apoptotic peaks were detected: one at premetamorphosis 1 and the second at prometamorphosis. PARP-1, a known molecular marker of apoptosis, was used to confirm the data obtained by counting pyknotic nuclei. In summary, proliferative and apoptotic waves display an inverse time-relationship through development, with apoptotic peaks coinciding with low proliferation phases. In a comparative perspective, amphibians follow a developmental pattern similar to other vertebrates, although with different timing.
Collapse
Affiliation(s)
- Claudia Pinelli
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Alfredo Sansone
- Department of Biology, University of Naples "Federico II", MSA Campus, Naples, Italy.,Institute of Neurophysiology and Cellular Biophysics, University of Göttingen, Göttingen, Germany
| | - Anna De Maio
- Department of Biology, University of Naples "Federico II", MSA Campus, Naples, Italy
| | - Antonietta Morgillo
- Department of Biology, University of Naples "Federico II", MSA Campus, Naples, Italy
| | - Anna Scandurra
- Department of Biology, University of Naples "Federico II", MSA Campus, Naples, Italy
| | - Biagio D'Aniello
- Department of Biology, University of Naples "Federico II", MSA Campus, Naples, Italy
| |
Collapse
|
5
|
Francisco-Morcillo J, Bejarano-Escobar R, Rodríguez-León J, Navascués J, Martín-Partido G. Ontogenetic cell death and phagocytosis in the visual system of vertebrates. Dev Dyn 2014; 243:1203-25. [PMID: 25130286 DOI: 10.1002/dvdy.24174] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 07/04/2014] [Accepted: 07/25/2014] [Indexed: 12/25/2022] Open
Abstract
Programmed cell death (PCD), together with cell proliferation, cell migration, and cell differentiation, is an essential process during development of the vertebrate nervous system. The visual system has been an excellent model on which to investigate the mechanisms involved in ontogenetic cell death. Several phases of PCD have been reported to occur during visual system ontogeny. During these phases, comparative analyses demonstrate that dying cells show similar but not identical spatiotemporally restricted patterns in different vertebrates. Additionally, the chronotopographical coincidence of PCD with the entry of specialized phagocytes in some regions of the developing vertebrate visual system suggests that factors released from degenerating cells are involved in the cell migration of macrophages and microglial cells. Contradicting this hypothesis however, in many cases the cell corpses generated during degeneration are rapidly phagocytosed by neighboring cells, such as neuroepithelial cells or Müller cells. In this review, we describe the occurrence and the sites of PCD during the morphogenesis and differentiation of the retina and optic pathways of different vertebrates, and discuss the possible relationship between PCD and phagocytes during ontogeny.
Collapse
|
6
|
Bejarano-Escobar R, Blasco M, Durán AC, Martín-Partido G, Francisco-Morcillo J. Chronotopographical distribution patterns of cell death and of lectin-positive macrophages/microglial cells during the visual system ontogeny of the small-spotted catshark Scyliorhinus canicula. J Anat 2013; 223:171-84. [PMID: 23758763 DOI: 10.1111/joa.12071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2013] [Indexed: 01/15/2023] Open
Abstract
The patterns of distribution of TUNEL-positive bodies and of lectin-positive phagocytes were investigated in the developing visual system of the small-spotted catshark Scyliorhinus canicula, from the optic vesicle stage to adulthood. During early stages of development, TUNEL-staining was mainly found in the protruding dorsal part of the optic cup and in the presumptive optic chiasm. Furthermore, TUNEL-positive bodies were also detected during detachment of the embryonic lens. Coinciding with the developmental period during which ganglion cells began to differentiate, an area of programmed cell death occurred in the distal optic stalk and in the retinal pigment epithelium that surrounds the optic nerve head. The topographical distribution of TUNEL-positive bodies in the differentiating retina recapitulated the sequence of maturation of the various layers and cell types following a vitreal-to-scleral gradient. Lectin-positive cells apparently entered the retina by the optic nerve head when the retinal layering was almost complete. As development proceeded, these labelled cells migrated parallel to the axon fascicles of the optic fiber layer and then reached more external layers by radial migration. In the mature retina, lectin-positive cells were confined to the optic fiber layer, ganglion cell layer and inner plexiform layer. No evident correlation was found between the chronotopographical pattern of distribution of TUNEL-positive bodies and the pattern of distribution of lectin-labelled macrophages/microglial cells during the shark's visual system ontogeny.
Collapse
Affiliation(s)
- Ruth Bejarano-Escobar
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | | | | | | | | |
Collapse
|
7
|
Han W, Han YP, Wang ZR. Apoptosis and differentiation in presumptive neural retina and presumptive retinal pigmented epithelium during early eye development in toad, Bufo raddei strauch. Russ J Dev Biol 2012. [DOI: 10.1134/s1062360412060033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
8
|
Kwan KM, Otsuna H, Kidokoro H, Carney KR, Saijoh Y, Chien CB. A complex choreography of cell movements shapes the vertebrate eye. Development 2012; 139:359-72. [PMID: 22186726 PMCID: PMC3243097 DOI: 10.1242/dev.071407] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Optic cup morphogenesis (OCM) generates the basic structure of the vertebrate eye. Although it is commonly depicted as a series of epithelial sheet folding events, this does not represent an empirically supported model. Here, we combine four-dimensional imaging with custom cell tracking software and photoactivatable fluorophore labeling to determine the cellular dynamics underlying OCM in zebrafish. Although cell division contributes to growth, we find it dispensable for eye formation. OCM depends instead on a complex set of cell movements coordinated between the prospective neural retina, retinal pigmented epithelium (RPE) and lens. Optic vesicle evagination persists for longer than expected; cells move in a pinwheel pattern during optic vesicle elongation and retinal precursors involute around the rim of the invaginating optic cup. We identify unanticipated movements, particularly of central and peripheral retina, RPE and lens. From cell tracking data, we generate retina, RPE and lens subdomain fate maps, which reveal novel adjacencies that might determine corresponding developmental signaling events. Finally, we find that similar movements also occur during chick eye morphogenesis, suggesting that the underlying choreography is conserved among vertebrates.
Collapse
Affiliation(s)
- Kristen M Kwan
- Department of Neurobiology and Anatomy, Salt Lake City, UT 84132, USA.
| | | | | | | | | | | |
Collapse
|
9
|
Bejarano-Escobar R, Holguín-Arévalo MS, Montero JA, Francisco-Morcillo J, Martín-Partido G. Macrophage and microglia ontogeny in the mouse visual system can be traced by the expression of Cathepsins B and D. Dev Dyn 2011; 240:1841-55. [PMID: 21648018 DOI: 10.1002/dvdy.22673] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2011] [Indexed: 01/11/2023] Open
Abstract
Here, we show a detailed chronotopographical analysis of cathepsin B and D expression during development of the mouse visual system. Both proteases were detected in large rounded/ameboid cells usually located in close relationship with prominent sites of extensive physiological cell death. In concordance with their morphological features and topographical distribution, we demonstrate that expressing cells corresponded with macrophages and microglial precursors. We found that as microglial precursors differentiated the expression of both cathepsins was down-regulated. Of interest, cathepsin B and D transcripts were never observed in degenerating cells. Our findings point to a role for cathepsin D and B in cell debris degradation after apoptotic processes rather than promoting cell death, as proposed for other developmental models. Additionally their pattern of expression suggests a role in the maturation of the microglial precursors.
Collapse
Affiliation(s)
- Ruth Bejarano-Escobar
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | | | | | | | | |
Collapse
|
10
|
Cell Death as a Regulator of Cerebellar Histogenesis and Compartmentation. THE CEREBELLUM 2010; 10:373-92. [DOI: 10.1007/s12311-010-0222-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
11
|
Bejarano-Escobar R, Blasco M, DeGrip WJ, Oyola-Velasco JA, Martín-Partido G, Francisco-Morcillo J. Eye development and retinal differentiation in an altricial fish species, the senegalese sole (Solea senegalensis, Kaup 1858). JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2010; 314:580-605. [DOI: 10.1002/jez.b.21363] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 04/10/2010] [Accepted: 05/17/2010] [Indexed: 12/19/2022]
|
12
|
Sakaguchi DS, Hoffelen SV, Greenlee MHW, Harper MM, Au DT. Cell birth and death in the developing retina of the Brazilian opossum, Monodelphis domestica. Brain Res 2008; 1195:28-42. [DOI: 10.1016/j.brainres.2007.12.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 12/03/2007] [Accepted: 12/06/2007] [Indexed: 10/22/2022]
|
13
|
Chavarría T, Valenciano AI, Mayordomo R, Egea J, Comella JX, Hallböök F, de Pablo F, de la Rosa EJ. Differential, age-dependent MEK-ERK and PI3K-Akt activation by insulin acting as a survival factor during embryonic retinal development. Dev Neurobiol 2007; 67:1777-88. [PMID: 17659595 DOI: 10.1002/dneu.20554] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Programmed cell death is a genuine developmental process of the nervous system, affecting not only projecting neurons but also proliferative neuroepithelial cells and young neuroblasts. The embryonic chick retina has been employed to correlate in vivo and in vitro studies on cell death regulation. We characterize here the role of two major signaling pathways, PI3K-Akt and MEK-ERK, in controlled retinal organotypic cultures from embryonic day 5 (E5) and E9, when cell death preferentially affects proliferating neuroepithelial cells and ganglion cell neurons, respectively. The relative density of programmed cell death in vivo was much higher in the proliferative and early neurogenic stages of retinal development (E3-E5) than during neuronal maturation and synaptogenesis (E8-E19). In organotypic cultures from E5 and E9 retinas, insulin, as the only growth factor added, was able to completely prevent cell death induced by growth factor deprivation. Insulin activated both the PI3K-Akt and the MEK-ERK pathways. Insulin survival effect, however, was differentially blocked at the two stages. At E5, the effect was blocked by MEK inhibitors, whereas at E9 it was blocked by PI3K inhibitors. The cells which were found to be dependent on insulin activation of the MEK-ERK pathway at E5 were mostly proliferative neuroepithelial cells. These observations support a remarkable specificity in the regulation of early neural cell death.
Collapse
Affiliation(s)
- Teresa Chavarría
- Department of Cellular and Molecular Physiopathology, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Morcillo J, Martínez-Morales JR, Trousse F, Fermin Y, Sowden JC, Bovolenta P. Proper patterning of the optic fissure requires the sequential activity of BMP7 and SHH. Development 2006; 133:3179-90. [PMID: 16854970 DOI: 10.1242/dev.02493] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The optic disc develops at the interface between optic stalk and retina,and enables both the exit of visual fibres and the entrance of mesenchymal cells that will form the hyaloid artery. In spite of the importance of the optic disc for eye function, little is known about the mechanisms that control its development. Here, we show that in mouse embryos, retinal fissure precursors can be recognised by the expression of netrin 1 and the overlapping distribution of both optic stalk (Pax2, Vax1) and ventral neural retina markers (Vax2, Raldh3). We also show that in the absence of Bmp7, fissure formation is not initiated. This absence is associated with a reduced cell proliferation and apoptosis in the proximoventral quadrant of the optic cup, lack of the hyaloid artery, optic nerve aplasia, and intra-retinal misrouting of RGC axons. BMP7 addition to organotypic cultures of optic vesicles from Bmp7-/- embryos rescues Pax2 expression in the ventral region, while follistatin, a BMP7 antagonist, prevents it in early, but not in late, optic vesicle cultures from wild-type embryos. The presence of Pax2-positive cells in late optic cup is instead abolished by interfering with Shh signalling. Furthermore, SHH addition re-establishes Pax2 expression in late optic cups derived from ocular retardation (or) embryos, where optic disc development is impaired owing to the near absence of SHH-producing RGC. Collectively, these data indicate that BMP7 is required for retinal fissure formation and that its activity is needed, before SHH signalling, for the generation of PAX2-positive cells at the optic disc.
Collapse
Affiliation(s)
- Julian Morcillo
- Departamento de Neurobiología del Desarrollo, Instituto Cajal, CSIC, Dr Arce 37, Madrid 28002, Spain
| | | | | | | | | | | |
Collapse
|
15
|
Duenker N. Transforming growth factor-beta (TGF-beta) and programmed cell death in the vertebrate retina. ACTA ACUST UNITED AC 2006; 245:17-43. [PMID: 16125544 DOI: 10.1016/s0074-7696(05)45002-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Programmed cell death (PCD) is a precisely regulated phenomenon essential for the homeostasis of multicellular organisms. Developmental systems, particularly the nervous system, have provided key observations supporting the physiological role of PCD. We have recently shown that transforming growth factor-beta (TGF-beta) plays an important role in mediating ontogenetic PCD in the nervous system. As part of the central nervous system the developing retina serves as an ideal model system for investigating apoptotic processes during neurogenesis in vivo as it is easily accessible experimentally and less complex due to its limited number of different neurons. This review summarizes data indicating a pivotal role of TGF-beta in mediating PCD in the vertebrate retina. The following topics are discussed: expression of TGF-beta isoforms and receptors in the vertebrate retina, the TGF-beta signaling pathway, functions and molecular mechanisms of PCD in the nervous system, TGF-beta-mediated retinal apoptosis in vitro and in vivo, and interactions of TGF-beta with other pro- and anti-apoptotic factors.
Collapse
Affiliation(s)
- Nicole Duenker
- Institute for Anatomy, Department of Neuroanatomy, University of Duisburg-Essen, 45122 Essen, Germany
| |
Collapse
|
16
|
Franke AG, Gubbe C, Beier M, Duenker N. Transforming growth factor-β and bone morphogenetic proteins: Cooperative players in chick and murine programmed retinal cell death. J Comp Neurol 2006; 495:263-78. [PMID: 16440295 DOI: 10.1002/cne.20869] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Transforming growth factor-beta (TGF-beta) and bone morphogenetic protein (BMP) are extracellular molecules known to mediate programmed cell death (PCD) in the developing retina. In the present study, we investigated the expression profiles and activity levels of ligands and receptors of the TGF-beta and BMP4 family during the physiological PCD periods of the developing chick and mouse retina and possible interactions of both proapoptotic molecules in mediating apoptosis in chick and murine retinal whole-mount cultures. Immunocytochemical double-labeling studies with the established ganglion cell marker Islet revealed overlapping expression patterns for TGF-beta and BMP4 ligands and receptors on the surface of retinal ganglion cells. The biphasic peak of activity and expression levels of TGF-beta and BMP4 ligands and receptors, revealed by Western blots and mink lung epithelial cell (MLEC) assays, coincided with the two main periods of retinal chick and murine PCD. In organotypic retinal cultures, we were able to increase apoptosis over basal levels by application of recombinant TGF-beta or BMP4. Double-factor treatment induced an additional increase of apoptosis, suggesting a cooperation of both proapoptotic pathways. A significant increase in the number of apoptotic cells in the ganglion cell layer was observed in a TUNEL staining of retinal whole mounts treated with recombinant TGF-beta or BMP4, suggesting a concerted action of both factors in triggering ganglion cell death. Blockage experiments revealed that both pathways do not interact at the ligand, receptor, or Smad protein level but converge at the transcriptional level of the TGF-beta immediate-early response gene TIEG and the transcriptional coactivator Gcn5.
Collapse
Affiliation(s)
- Andreas G Franke
- Department of Neuroanatomy, Center of Anatomy, University of Goettingen, 37075 Goettingen, Germany
| | | | | | | |
Collapse
|
17
|
Rodríguez-Gallardo L, Lineros-Domínguez MDC, Francisco-Morcillo J, Martín-Partido G. Macrophages during retina and optic nerve development in the mouse embryo: relationship to cell death and optic fibres. ACTA ACUST UNITED AC 2005; 210:303-16. [PMID: 16217650 DOI: 10.1007/s00429-005-0051-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2005] [Indexed: 10/25/2022]
Abstract
We compared the spatial and temporal patterns of distribution of macrophages, with patterns of naturally occurring cell death and optic fibre growth during early retina and optic nerve development, in the mouse. We used embryos between day 10 of embryogenesis (E10; before the first optic fibres are generated in the retina) and E13 (when the first optic fibres have crossed the chiasmatic anlage). The macrophages and optic axons were identified by immunocytochemistry, and the apoptotic cells were detected by the TUNEL technique, which specifically labels fragmented DNA. Cell death was observed in the retina and the optic stalk long before the first optic axons appeared in either region. Subsequently, specialized F4/80-positive phagocytes were detected in chronological and topographical coincidence with cell death, which disappeared progressively. As development proceeded, the pioneer ganglion cell axons reached the regions where the macrophages were located. As the number of optic fibres increased, the macrophages disappeared. Therefore, cell death, accompanied by macrophages, preceded the growth of fibres in the retina and the optic nerve. Moreover, these macrophages synthesized NGF and the optic axons were p75 neurotrophin receptor (p75(NTR))- and TrkA-positive. These findings suggest that macrophages may be involved in optic axon guidance and fasciculation.
Collapse
Affiliation(s)
- Lucía Rodríguez-Gallardo
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Avda de Elvas s/n, 06071, Badajoz, Spain.
| | | | | | | |
Collapse
|
18
|
Candal E, Anadón R, DeGrip WJ, Rodríguez-Moldes I. Patterns of cell proliferation and cell death in the developing retina and optic tectum of the brown trout. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 154:101-19. [PMID: 15617760 DOI: 10.1016/j.devbrainres.2004.10.008] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/10/2004] [Indexed: 10/26/2022]
Abstract
We have analyzed the patterns of cell proliferation and cell death in the retina and optic tectum of the brown trout (Salmo trutta fario) throughout embryonic and postembryonic stages. Cell proliferation was detected by immunohistochemistry with an antibody against the proliferating cell nuclear antigen (PCNA), and apoptosis by means of the TUNEL method. Haematoxylin and DAPI staining were also used to demonstrate apoptotic cells. Photoreceptor cell differentiation was assessed by immunohistochemistry with antibodies against opsins. Throughout embryonic development, PCNA-immunoreactive (PCNA-ir) cells become progressively restricted to the peripheral growth zone of the retina, which appears to be the principal source of new retinal cells from late embryos to adults. However, some PCNA-ir cells are observed secondarily in the differentiated retina, first in the inner nuclear layer of 15-mm alevins and later in the outer nuclear layer of 16-mm alevins, after differentiation of the first rods in the central retina, as demonstrated with opsin immunocytochemistry. Our observations also support the view that the PCNA-ir cells observed secondarily in the INL of the central retina of alevins are photoreceptor precursors. The number and distribution of apoptotic cells in the retina and optic tectum of the trout change throughout development, allowing distinction of several waves of apoptosis. Cell death is detected in proliferating areas at early stages, then in postmitotic or differentiating areas, and later concurring temporal and spatially with the establishment of visual circuits, thus indicating a relationship between apoptosis and proliferation, differentiation and synaptogenesis.
Collapse
Affiliation(s)
- Eva Candal
- Department of Cell Biology and Ecology, Faculty of Biology, University of Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | | | | | | |
Collapse
|
19
|
Leu ST, Jacques SAL, Wingerd KL, Hikita ST, Tolhurst EC, Pring JL, Wiswell D, Kinney L, Goodman NL, Jackson DY, Clegg DO. Integrin α4β1 function is required for cell survival in developing retina. Dev Biol 2004; 276:416-30. [PMID: 15581875 DOI: 10.1016/j.ydbio.2004.09.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2004] [Revised: 08/31/2004] [Accepted: 09/01/2004] [Indexed: 11/24/2022]
Abstract
In the retina, integrins in the beta1 family have been shown to be important in many phases of neuronal development, particularly neuroblast migration and axon outgrowth. However, the functions of specific integrin heterodimers are not well defined. In this study, we investigated the functions of beta1 integrins in developing chicken retina by expression of a dominant-negative beta1A construct using a replication-competent retrovirus. Inhibition of integrins using this approach resulted in alteration of cell morphology and increased apoptosis, but did not preclude migration and axon elongation. In an attempt to identify which specific beta1 heterodimer was important, expression and function of the alpha4beta1 heterodimer were also investigated. At early developmental stages, alpha4 protein and mRNA were detected in undifferentiated neuroblasts throughout the retina. At later stages, expression was confined to retinal ganglion cells (RGCs) and amacrine cells. A small molecule antagonist of alpha4 integrins was shown to inhibit neurite outgrowth on recombinant soluble vascular cell adhesion molecule-1 (VCAM-1), a known ligand of alpha4beta1. Introduction of alpha4 antagonist in vivo gave rise to increased apoptosis and led to a thinning of the retina and reduced numbers of retinal ganglion cells (RGCs). We conclude that the integrin alpha4beta1 is important for survival of developing retinal neurons, including RGCs.
Collapse
Affiliation(s)
- Sergiu T Leu
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Mayordomo R, Valenciano AI, de la Rosa EJ, Hallböök F. Generation of retinal ganglion cells is modulated by caspase-dependent programmed cell death. Eur J Neurosci 2003; 18:1744-50. [PMID: 14622209 DOI: 10.1046/j.1460-9568.2003.02891.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Programmed cell death occurs during both early and late neural development. The mechanisms for the regulation and execution of the early cell death as well as its developmental role are still not fully understood. In this work we have studied the early programmed cell death in the retinal neuroepithelium. Apoptotic cells were selectively located around the optic nerve head in the retinal neuroepithelium of 2- to 6-day-old chick embryos. TUNEL-positive cells and cells which were immunostained for activated caspase-3 showed overlapping distributions suggesting that caspase-3 is involved in the early retinal cell death. Caspase-3 involvement in early retinal cell death was also demonstrated by in vivo treatment with caspase inhibitors z-DEVD-fmk and Boc-D-fmk. After 6 h of treatment, the number of TUNEL-positive cells was reduced by 50%. Sustained treatments (20 h) resulted in a slight widening in the central part of the neural retina but the retinal ganglion cell axons maintained their organization and navigation towards the optic fissure. The most prominent result after inhibition of cell death was an increase in the number of retinal ganglion cells which also produced an enlargement of the ganglion cell layer and an increased number of ganglion cell axons. In conclusion, our results show that caspase-dependent programmed cell death occurs in the embryonic chick retina and that it plays a role to modulate the generation of retinal ganglion cells.
Collapse
|
21
|
Mu H, Ohta K, Kuriyama S, Shimada N, Tanihara H, Yasuda K, Tanaka H. Equarin, a novel soluble molecule expressed with polarity at chick embryonic lens equator, is involved in eye formation. Mech Dev 2003; 120:143-55. [PMID: 12559487 DOI: 10.1016/s0925-4773(02)00423-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The lens plays an important role in eye development. To investigate the molecular mechanisms involved, we used signal sequence trap screens with a chicken lens cDNA library and identified a novel secreted molecule, equarin. Equarin encodes consensus repeat domains conserved in human SRPX and mouse Urb. In the embryonic eye, equarin transcript is detected exclusively in the lens, and persists in the lens equatorial region in a high-dorsal-to-low-ventral gradient. In vitro analysis of equarin protein indicated that after translation, it is modified, cleaved, and secreted to extracellular locations. Microinjection of equarin mRNA into Xenopus embryos induced abnormal eye development. These data suggest that equarin is involved in eye formation.
Collapse
Affiliation(s)
- Hong Mu
- Division of Developmental Neurobiology, Kumamoto University Graduate School of Medical Sciences, Honjo 2-2-1, Kumamoto 860-0811, Japan
| | | | | | | | | | | | | |
Collapse
|
22
|
Hutson LD, Bothwell M. Expression and function of Xenopus laevis p75(NTR) suggest evolution of developmental regulatory mechanisms. JOURNAL OF NEUROBIOLOGY 2001; 49:79-98. [PMID: 11598917 DOI: 10.1002/neu.1067] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Neurotrophins signal through two different classes of receptors, members of the trk family of receptor tyrosine kinases, and p75 neurotrophin receptor (p75(NTR)), a member of the tumor necrosis factor receptor family. While neurotrophin binding to trks results in, among other things, increased cell survival, p75(NTR) has enigmatically been implicated in promoting both survival and cell death. Which of these two signals p75(NTR) imparts depends on the specific cellular context. Xenopus laevis is an excellent system in which to study p75(NTR) function in vivo because of its amenability to experimental manipulation. We therefore cloned partial cDNAs of two p75(NTR) genes from Xenopus, which we have termed p75(NTR)a and p75(NTR)b. We then cloned two different cDNAs, both of which encompass the full coding region of p75(NTR)a. Early in development both p75(NTR)a and p75(NTR)b are expressed in developing cranial ganglia and presumptive spinal sensory neurons, similar to what is observed in other species. Later, p75(NTR)a expression largely continues to parallel p75(NTR) expression in other species. However, Xenopus p75(NTR)a is additionally expressed in the neuroepithelium of the anterior telencephalon, all layers of the retina including the photoreceptor layer, and functioning axial skeletal muscle. Finally, misexpression of full length p75(NTR) and each of two truncated mutants in developing retina reveal that p75(NTR) probably signals for cell survival in this system. This result contrasts with the reported role of p75(NTR) in developing retinae of other species, and the possible implications of this difference are discussed.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Apoptosis
- Central Nervous System/embryology
- Central Nervous System/growth & development
- Central Nervous System/metabolism
- Chickens
- Consensus Sequence
- Cranial Nerves/embryology
- Cranial Nerves/growth & development
- Cranial Nerves/metabolism
- DNA, Complementary/genetics
- Embryo, Nonmammalian/metabolism
- Evolution, Molecular
- Eye Proteins/biosynthesis
- Eye Proteins/genetics
- Eye Proteins/physiology
- Gene Expression Regulation, Developmental
- Genes
- Genes, Synthetic
- Humans
- In Situ Hybridization
- In Situ Nick-End Labeling
- Larva
- Molecular Sequence Data
- Muscle Proteins/biosynthesis
- Muscle Proteins/genetics
- Muscle Proteins/physiology
- Muscle, Skeletal/embryology
- Muscle, Skeletal/metabolism
- Nerve Tissue Proteins/biosynthesis
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/physiology
- Neurons, Afferent/metabolism
- Organ Specificity
- RNA, Messenger/genetics
- Rats
- Receptor, Nerve Growth Factor
- Receptors, Nerve Growth Factor/biosynthesis
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/physiology
- Recombinant Fusion Proteins/physiology
- Retina/embryology
- Retina/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Alignment
- Sequence Homology, Amino Acid
- Species Specificity
- Transfection
- Tumor Necrosis Factor-alpha/pharmacology
- Xenopus laevis/embryology
- Xenopus laevis/genetics
- Xenopus laevis/growth & development
Collapse
Affiliation(s)
- L D Hutson
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA.
| | | |
Collapse
|
23
|
Abstract
The bone morphogenetic protein (BMP) expression in vertebrates suggests a reiterative function of these molecules during eye development. However, genetic analysis in mice has provided only partial information. Using the chick embryo as a model system, we have analyzed possible additional functions of BMP4 during optic cup formation. Here we describe the expression pattern of Bmp4 and Bmp7 and we show that, in contrast to the mouse, the prospective lens placode ectoderm expresses high levels of Bmp4 but no Bmp7. After optic vesicle invagination, Bmp4 is expressed in the prospective dorsal neural retina, where BmprIA, BmprII, and Smad1, components of the BMP4 signal transduction pathway, are also expressed. In toto terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end-labeling analysis shows that the dorsal optic cup is the site of a spatiotemporally restricted apoptosis, which parallels the expression not only of Bmp4 but also of Msx1 and Msx2, genes implicated in BMP4-mediated apoptosis. The use of optic vesicle cultures as well as in ovo local addition of BMP4 and its antagonist Noggin proves that the local activity of BMP4 is responsible for programmed cell death in the dorsal optic cup. In addition, we show that Noggin is able to reduce the rate of cell proliferation in the dorsal part of the optic cup whereas BMP4 increases the number of BrdU-positive cells in retina cultures. These results provide evidence that BMP4 contributes to eye development by promoting cell proliferation and programmed cell death.
Collapse
|
24
|
Dünker N, Schuster N, Krieglstein K. TGF-β modulates programmed cell death in the retina of the developing chick embryo. Development 2001; 128:1933-42. [PMID: 11493517 DOI: 10.1242/dev.128.11.1933] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Programmed cell death (PCD) is a key phenomenon in the regulation of cell number in multicellular organisms. We have shown that reduction of endogenous transforming growth factor β (TGF-β) prevents apoptotic PCD of neurons in the developing peripheral and central nervous system, suggesting that TGF-β is an important mediator of ontogenetic neuron death. Previous studies suggested that there are other pro-apoptotic molecules, nerve growth factor (NGF) and brain-derived neurotrophic factor, that induce cell death in the nervous system. In the developing chick retina, NGF induces PCD by activation of the p75 receptor. We have studied the role of TGF-β and its putative interdependence with NGF-mediated PCD in the chick retina. We found that TGF-β is present in the developing chick retina during the period of PCD and is essentially required to regulate PCD of retinal cells. TGF-β2, TGF-β3 and the ligand-binding TGF-β receptor can be detected immunocytochemically in the central retina, a region where apoptosis is most prominent during the early period of PCD. Application of a TGF-β-neutralizing antibody to chick embryos in ovo resulted in a decrease in the number of TUNEL-positive cells and a reduction of free nucleosome levels. In terms of magnitude, reduction of PCD caused by the neutralization of endogenous TGF-β was equivalent to that seen after anti-NGF application. Neutralization of both factors did not result in a further decrease in apoptosis, indicating that NGF and TGF-β may act on the same cell population. Furthermore, neutralization of TGF-β did not affect the expression of NGF or the p75-receptor. Our results suggest that TGF-β and NGF are both required to regulate cell death in the chick retina in vivo.
Collapse
Affiliation(s)
- N Dünker
- University of Saarland, Department of Anatomy, D-66421 Homburg/Saar, Germany
| | | | | |
Collapse
|
25
|
Karlsson M, Mayordomo R, Reichardt LF, Catsicas S, Karten HJ, Hallböök F. Nerve growth factor is expressed by postmitotic avian retinal horizontal cells and supports their survival during development in an autocrine mode of action. Development 2001; 128:471-9. [PMID: 11171331 PMCID: PMC2710126 DOI: 10.1242/dev.128.4.471] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cell death in the developing retina is regulated, but so far little is known about what factors regulate the cell death. Several neurotrophic factors and receptors, including the neurotrophins and Trk receptors, are expressed during the critical time. We have studied the developing avian retina with respect to the role of nerve growth factor (NGF) in these processes. Our starting point for the work was that NGF and its receptor TrkA are expressed in a partially overlapping pattern in the inner nuclear layer of the developing retina. Our results show that TrkA and NGF-expressing cells are postmitotic. The first NGF-expressing cells were found on the vitreal side of the central region of E5.5-E6 retina. This pattern changed and NGF-expressing cells identified as horizontal cells were later confined to the external inner nuclear layer. We show that these horizontal cells co-express TrkA and NGF, unlike a subpopulation of amacrine cells that only expresses TrkA. In contrast to the horizontal cells, which survive, the majority of the TrkA-expressing amacrine cells die during a period of cell death in the inner nuclear layer. Intraocular injections of NGF protein rescued the dying amacrine cells and injection of antisense oligonucleotides for NGF that block its synthesis, caused death among the TrkA-expressing horizontal cells, which normally would survive. Our results suggest that NGF supports the survival of TrkA expressing avian horizontal cells in an autocrine mode of action in the retina of E10-E12 chicks. The cells co-express TrkA and NGF and the role for NGF is to maintain the TrkA-expressing horizontal cells. The TrkA-expressing amacrine cells are not supported by NGF and subsequently die. In addition to the effect on survival, our results suggest that NGF plays a role in horizontal cell plasticity.
Collapse
Affiliation(s)
- Miriam Karlsson
- Department of Neuroscience, Unit of Developmental Neuroscience, Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden
| | - Raquel Mayordomo
- Department of Neuroscience, Unit of Developmental Neuroscience, Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden
| | | | - Stefan Catsicas
- IBCM, Medical Faculty, University of Lausanne, Lausanne, Switzerland
| | - Harvey J. Karten
- Department of Neuroscience, University of California, San Diego, La Jolla, CA 92093, USA
| | - Finn Hallböök
- Department of Neuroscience, Unit of Developmental Neuroscience, Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden
| |
Collapse
|
26
|
Abstract
The important effect of cell death on projecting neurons during development is well established. However, this mainstream research might have diverted recognition of the cell death that occurs at earlier stages of neural development, affecting proliferating neural precursor cells and young neuroblasts. In this article, we briefly present observations supporting the occurrence of programmed cell death during early neural development in a regulated fashion that to some extent parallels the death of projecting neurons lacking neurotrophic support. These findings raise new questions, in particular the magnitude and the role of this early neural cell death.
Collapse
Affiliation(s)
- E J de la Rosa
- Dept of Cell and Developmental Biology, Centro de Investigaciones Biológicas, CSIC, Velázquez 144, E-28006, Madrid, Spain
| | | |
Collapse
|
27
|
Abstract
The signaling cascade Ras/Raf/mitogen-activated protein kinases modulates cell proliferation, differentiation, and survival, all key cellular processes during neural development. To better define the in vivo role of Raf during chick retinal neurogenesis, we interfered with Raf-dependent signaling during days 4.5 to 7.5 of embryonic development by expressing a dominant negative mutant of c-Raf (DeltaRaf), which blocks Ras-dependent Raf activation, and by overexpressing wild-type c-Raf. DeltaRaf expression induced an increase in cell death by apoptosis, whereas it did not affect overall cell proliferation and differentiation. In parallel, the number of Islet-1/2-positive and TUJ1-positive retinal ganglion cells were diminished in their definitive layer, whereas there was an increase in the number of mislocated Islet-1/2-positive cells. This disturbed morphogenesis correlated with a disruption of the optic fiber layer. Conversely, c-Raf overexpression caused moderate opposite effects on apoptosis. These results frame in vivo early neurogenesis processes in which c-Raf is essential.
Collapse
|
28
|
Díaz B, Serna J, De Pablo F, de la Rosa EJ. In vivo regulation of cell death by embryonic (pro)insulin and the insulin receptor during early retinal neurogenesis. Development 2000; 127:1641-9. [PMID: 10725240 DOI: 10.1242/dev.127.8.1641] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Programmed cell death is an established developmental process in the nervous system. Whereas the regulation and the developmental role of neuronal cell death have been widely demonstrated, the relevance of cell death during early neurogenesis, the cells affected and the identity of regulatory local growth factors remain poorly characterized. We have previously described specific in vivo patterns of apoptosis during early retinal neurogenesis, and that exogenous insulin acts as survival factor (Diaz, B., Pimentel, B., De Pablo, F. and de la Rosa, E. J. (1999) Eur. J. Neurosci. 11, 1624–1632). Proinsulin mRNA was found to be expressed broadly in the early embryonic chick retina, and decreased later between days 6 and 8 of embryonic development, when there was increased expression of insulin-like growth factor I mRNA, absent or very scarce at earlier stages. Consequently, we studied whether proinsulin and/or insulin ((pro)insulin) action in prevention of cell death has physiological relevance during early neural development. In ovo treatment at day 2 of embryonic development with specific antibodies against (pro)insulin or the insulin receptor induced apoptosis in the neuroretina. The distribution of apoptotic cells two days after the blockade was similar to naturally occurring cell death, as visualized by TdT-mediated dUTP nick end labeling. The apoptosis induced by the insulin receptor blockade preferentially affected to the Islet1/2 positive cells, that is, the differentiated retinal ganglion cells. In parallel, the insulin survival effect on cultured retinas correlated with the activation of Akt to a greater extent than with the activation of MAP kinase. These results suggest that the physiological cell death occurring in early stages of retinal development is regulated by locally produced (pro)insulin through the activation of the Akt survival pathway.
Collapse
Affiliation(s)
- B Díaz
- Department of Cell and Developmental Biology, Centro de Investigaciones Biológicas, CSIC, Velázquez 144, E-28006 Madrid, Spain
| | | | | | | |
Collapse
|
29
|
Mar�n-Teva JL, Cuadros MA, Calvente R, Almendros A, Navascu�s J. Naturally occurring cell death and migration of microglial precursors in the quail retina during normal development. J Comp Neurol 1999. [DOI: 10.1002/(sici)1096-9861(19990920)412:2<255::aid-cne6>3.0.co;2-h] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
30
|
Díaz B, Pimentel B, de Pablo F, de La Rosa EJ. Apoptotic cell death of proliferating neuroepithelial cells in the embryonic retina is prevented by insulin. Eur J Neurosci 1999; 11:1624-32. [PMID: 10215915 DOI: 10.1046/j.1460-9568.1999.00577.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The role of programmed cell death is well established for connecting neurons. Conversely, much less is known about apoptosis affecting proliferating neuroepithelial cells. Chick retina from day 4 to day 6 of embryonic development (E), essentially proliferative, presented a defined distribution of apoptotic cells during normal in vivo development, as visualized by TdT-mediated dUTP nick end labelling (TUNEL). Insulin, expressed in the early chick embryonic retina as proinsulin, attenuated apoptosis in growth factor-deprived organotypic culture of E5 retina. This effect was demonstrated both by TUNEL and by staining of pyknotic nuclei, as well as by release of nucleosomes. Application of a 1 h [methyl-3H]thymidine pulse in ovo at E5, followed by organotypic culture in the presence or absence of insulin, showed that this factor alone decreased the degradation of labelled DNA to nucleosomes by 40%, as well as the proportion of labelled pyknotic nuclei. Both features are a consequence of apoptosis affecting neuroepithelial cells, which were in S-phase or shortly after. In addition, when the E5 embryos were maintained in ovo after the application of [methyl-3H]thymidine, 70% of the apoptotic retinal cells were labelled, indicating the in vivo prevalence of cell death among actively proliferating neuroepithelial cells. Apoptotic cell death is thus temporally and spatially regulated during proliferative stages of retinal neurogenesis, and embryonic proinsulin is presumably an endogenous protective factor.
Collapse
Affiliation(s)
- B Díaz
- Department of Cell and Developmental Biology, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | | | | | | |
Collapse
|
31
|
Tang Q, Rice DS, Goldowitz D. Disrupted retinal development in the embryonic belly spot and tail mutant mouse. Dev Biol 1999; 207:239-55. [PMID: 10049578 DOI: 10.1006/dbio.1998.9142] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Belly spot and tail (Bst) semidominant mutation, mapped to mouse Chromosome 16, leads to developmental defects of the eye, skeleton, and coat pigmentation. In the eye, the mutant phenotype is characterized by the presence of retinal colobomas, a paucity of retinal ganglion cells, and axon misrouting. The severity of defects in the Bst/+ retina is variable among individuals and is often asymmetric. In order to determine the role of the Bst locus during retinal morphogenesis, we searched for the earliest observable defects in the developing eye. We examined the retinas of Bst/+ and +/+ littermates from embryonic day 9.5 (E9.5) through E13.5 and measured retinal size, cell density, cell death, mitotic index, and cell birth index. We have found that development of the Bst/+ retina is notably dilatory by as early as E10.5. The affected retinas are smaller than their wildtype counterparts, and optic fissure fusion is delayed. In the mutant, there is a marked lag in the exit of retinal cells from the mitotic cycle, even though there are no observable differences in the rate of cellular proliferation or cell death between the two groups. We hypothesize that Bst regulates retinal cell differentiation and that variability of structural defects in the mutant, such as those affecting optic fissure fusion, is a reflection of the extent of developmental delay brought about by the Bst mutation.
Collapse
Affiliation(s)
- Q Tang
- Center for Neuroscience, University of Tennessee Memphis, 855 Monroe Avenue, Memphis, Tennessee, 38163, USA
| | | | | |
Collapse
|
32
|
|
33
|
Karlsson M, Clary DO, Lefcort FB, Reichardt LF, Karten HJ, Hallb��k F. Nerve growth factor receptor TrkA is expressed by horizontal and amacrine cells during chicken retinal development. J Comp Neurol 1998. [DOI: 10.1002/(sici)1096-9861(19981026)400:3<408::aid-cne9>3.0.co;2-c] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
34
|
Abstract
While nerve growth factor (NGF) is best known for its trophic functions, recent experiments indicate that it can also cause cell death during development by activating the neurotrophin receptor p75. We now identify microglial cells as the source of NGF as a killing agent in the developing eye. When the retina is separated from the surrounding tissue before colonization by microglial cells, no NGF can be detected, and cell death is dramatically reduced. It is restored by the addition of microglial cells, an effect that is blocked by NGF antibodies. NGF adsorbed at the surface of beads, but not soluble NGF, mimics the killing action of microglial cells. These results indicate an active role for macrophages in neuronal death.
Collapse
Affiliation(s)
- J M Frade
- Max-Planck Institute of Neurobiology, Department of Neurobiochemistry, Planegg-Martinsried, Federal Republic of Germany
| | | |
Collapse
|
35
|
Navascués J, Moujahid A, Almendros A, Marin-Teva JL, Cuadros MA. Origin of microglia in the quail retina: central-to-peripheral and vitreal-to-scleral migration of microglial precursors during development. J Comp Neurol 1995; 354:209-28. [PMID: 7782499 DOI: 10.1002/cne.903540205] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The origin, migration, and differentiation of microglial precursors in the avascular quail retina during embryonic and posthatching development were examined in this study. Microglial precursors and developing microglia were immunocytochemically labeled with QH1 antibody in retinal whole mounts and sections. The retina was free of QH1+ macrophages at embryonic day 5 (E5). Ameboid QH1+ macrophages from the pecten entered the retina from E7 on. These macrophages spread from central to peripheral areas in the retina by migrating on the endfeet of the Müller cells and reached the periphery of the retina at E12. While earlier macrophages were migrating along the inner limiting membrane, other macrophages continued to enter the retina from the pecten until hatching (E16). From E9 on, macrophages were seen to colonize progressively more scleral retinal layers as development advanced. Macrophages first appeared in the ganglion cell layer at E9, in the inner plexiform layer at E12, and in the outer plexiform layer at E14. Therefore, it seems that macrophages first migrated tangentially along the inner retinal surface and then migrated from vitreal to scleral levels to gain access to the plexiform layers, where they differentiated into ramified microglia. Macrophages appeared to differentiate shortly after arrival in the plexiform layers, as poorly ramified QH1+ cells were seen as early as E12 in the inner plexiform layer and at E14 in the outer plexiform layer. Radial migration of macrophages toward the outer plexiform layer continued until posthatching day 3, after which retinal microglia showed an adult distribution pattern. We also observed numerous vitreal macrophages intimately adhered to the surface of the pecten during embryonic development, when macrophages migrated into the retina. These vitreal macrophages were not seen from hatching onwards, when no further macrophages entered the retina.
Collapse
Affiliation(s)
- J Navascués
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Granada, Spain
| | | | | | | | | |
Collapse
|
36
|
Cuadros MA, Martin C, R�os A, Mart�n-Partido G, Navascu�s J. Macrophages of hemangioblastic lineage invade the lens vesicle-ectoderm interspace during closure and detachment of the avian embryonic lens. Cell Tissue Res 1991. [DOI: 10.1007/bf00678718] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
37
|
Martín-Partido G, Navascués J. Macrophage-like cells in the presumptive optic pathways in the floor of the diencephalon of the chick embryo. JOURNAL OF NEUROCYTOLOGY 1990; 19:820-32. [PMID: 2292715 DOI: 10.1007/bf01186813] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In the suboptic necrotic centres (SONCs) of the chick embryo diencephalon floor, large numbers of cells die in Hamburger and Hamilton's (HH) developmental stages 14-23. Until recently, it was thought that in these centres, the fragments of dead cells were phagocytosed exclusively by neighboring healthy cells but not by specialized macrophages. We now report morphological evidence of macrophage-like cells within the SONCs of the chick embryo. The distinctive features of these cells are their more or less spherical shape, a nucleus with a thin band of heterochromatin just beneath the nuclear envelope, and cytoplasm showing abundant digestive vacuoles and mitochondria with an electron-lucent matrix. These cells are capable of undergoing mitosis, and selectively stain with the histochemical technique for acid phosphatase. The macrophage-like cells are rare in SONCs in stages HH14-20 and become much more abundant in developmental stages just before the disappearance of these necrotic centres, suggesting that they phagocytose debris from the last cells to die in the SONCs. Acid phosphatase-positive mesenchymal cells with morphological features similar to those of macrophage-like cells are seen in intimate relationship with the basal surface of the SONCs in places where the basal lamina is sometimes missing. These observations suggest that macrophage-like cells in the SONCs arise from the underlying mesenchyme. Free macrophage-like cells with mitotic capacity are also seen in the ventricular lumen adjacent to the apical surface of the diencephalon floor in zones related to the presumptive optic pathways. These cells phagocytose cell debris shed from both the SONCs and from the partially disorganized areas in the neuroepithelium. In these latter we have identified mesenchymal cells with morphological features similar to the macrophage-like cells in the process of traversing the neuroepithelium from the mesenchymal compartment toward the ventricular lumen, thus suggesting that the intraventricular macrophage-like cells arise from the mesenchyme underlying the diencephalon floor.
Collapse
Affiliation(s)
- G Martín-Partido
- Departamento de Ciencias Morfológicas y Biología Celular y Animal, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | | |
Collapse
|