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Embryonic Cerebellar Graft Morphology Differs in Two Mouse Models of Cerebellar Degeneration. THE CEREBELLUM 2020; 18:855-865. [PMID: 31418135 DOI: 10.1007/s12311-019-01067-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Cerebellar diseases causing substantial cell loss often lead to severe functional deficits and restoration of cerebellar function is difficult. Neurotransplantation therapy could become a hopeful method, but there are still many limitations and unknown aspects. Studies in a variety of cerebellar mutant mice reflecting heterogeneity of human cerebellar degenerations show promising results as well as new problems and questions to be answered. The aim of this work was to compare the development of embryonic cerebellar grafts in adult B6CBA Lurcher and B6.BR pcd mutant mice and strain-matched healthy wild type mice. Performance in the rotarod test, graft survival, structure, and volume was examined 2 months after the transplantation or sham-operation. The grafts survived in most of the mice of all types. In both B6CBA and B6.BR wild type mice and in pcd mice, colonization of the host's cerebellum was a common finding, while in Lurcher mice, the grafts showed a low tendency to infiltrate the host's cerebellar tissue. There were no significant differences in graft volume between mutant and wild type mice. Nevertheless, B6CBA mice had smaller grafts than their B6.BR counterparts. The transplantation did not improve the performance in the rotarod test. The study showed marked differences in graft integration into the host's cerebellum in two types of cerebellar mutants, suggesting disease-specific factors influencing graft fate.
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Sherkhane P, Kapfhammer JP. Chronic pharmacological blockade of the Na + /Ca 2+ exchanger modulates the growth and development of the Purkinje cell dendritic arbor in mouse cerebellar slice cultures. Eur J Neurosci 2017; 46:2108-2120. [PMID: 28715135 DOI: 10.1111/ejn.13649] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 07/11/2017] [Accepted: 07/11/2017] [Indexed: 01/22/2023]
Abstract
The Na+ /Ca2+ exchanger (NCX) is a bidirectional plasma membrane antiporter involved in Ca2+ homeostasis in eukaryotes. NCX has three isoforms, NCX1-3, and all of them are expressed in the cerebellum. Immunostaining on cerebellar slice cultures indicates that NCX is widely expressed in the cerebellum, including expression in Purkinje cells. The pharmacological blockade of the forward mode of NCX (Ca2+ efflux mode) by bepridil moderately inhibited growth and development of Purkinje cell dendritic arbor in cerebellar slice cultures. However, the blockade of the reverse mode (Ca2+ influx mode) by KB-R7943 severely reduced the dendritic arbor and induced a morphological change with thickened distal dendrites. The effect of KB-R7943 on dendritic growth was unrelated to the activity of voltage-gated calcium channels and was also apparent in the absence of bioelectrical activity indicating that it was mediated by NCX expressed in Purkinje cells. We have used additional NCX inhibitors including CB-DMB, ORM-10103, SEA0400, YM-244769, and SN-6 which have higher specificity for NCX isoforms and target either the forward, reverse, or both modes. These inhibitors caused a strong dendritic reduction similar to that seen with KB-R7943, but did not elicit thickening of distal dendrites. Our findings indicate that disturbance of the NCX-dependent calcium transport in Purkinje cells induces a reduction of dendritic arbor, which is presumably caused by changes in the calcium handling, and underline the importance of the calcium equilibrium for the dendritic development in cerebellar Purkinje cells.
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Affiliation(s)
- Pradeep Sherkhane
- Department of Biomedicine, Anatomical Institute, University of Basel, Pestalozzistrasse 20, CH-4056, Basel, Switzerland
| | - Josef P Kapfhammer
- Department of Biomedicine, Anatomical Institute, University of Basel, Pestalozzistrasse 20, CH-4056, Basel, Switzerland
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Tal E, Shiloh Y. Monitoring the ATM-Mediated DNA Damage Response in the Cerebellum Using Organotypic Cultures. Methods Mol Biol 2017; 1599:419-430. [PMID: 28477136 DOI: 10.1007/978-1-4939-6955-5_30] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The ATM gene and its protein product, the ATM protein kinase, were identified as a result of attempts to understand the molecular basis of the genetic disorder, ataxia-telangiectasia (A-T). The cardinal symptom of A-T is neurodegeneration expressed primarily as progressive cerebellar atrophy. A major tool in the investigation of ATM functions in the cerebellum is cerebellar organotypic cultures, which allow cerebellar slices to live in culture for several weeks without losing their viability and organization. These cultures are amenable to various treatments and manipulations and provide a close look at Purkinje cells in their almost natural environment. We optimized the protocol for establishing and maintaining these cultures and provide here examples of readouts of the DNA damage response in cerebellar organotypic cultures treated with a DNA-damaging agent.
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Affiliation(s)
- Efrat Tal
- The David and Inez Myers Laboratory for Cancer Research, Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Yosef Shiloh
- The David and Inez Myers Laboratory for Cancer Research, Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
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Kolinko Y, Cendelin J, Kralickova M, Tonar Z. Smaller Absolute Quantities but Greater Relative Densities of Microvessels Are Associated with Cerebellar Degeneration in Lurcher Mice. Front Neuroanat 2016; 10:35. [PMID: 27147979 PMCID: PMC4835681 DOI: 10.3389/fnana.2016.00035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 03/15/2016] [Indexed: 11/17/2022] Open
Abstract
Degenerative affections of nerve tissues are often accompanied by changes of vascularization. In this regard, not much is known about hereditary cerebellar degeneration. In this study, we compared the vascularity of the individual cerebellar components and the mesencephalon of 3-month-old wild type mice (n = 5) and Lurcher mutant mice, which represent a model of hereditary olivocerebellar degeneration (n = 5). Paraformaldehyde-fixed brains were processed into 18-μm thick serial sections with random orientation. Microvessels were visualized using polyclonal rabbit anti-laminin antibodies. Then, the stacks comprised of three 5-μm thick optical sections were recorded using systematic uniform random sampling. Stereological assessment was conducted based on photo-documentation. We found that each of the cerebellar components has its own features of vascularity. The greatest number and length of vessels were found in the granular layer; the number of vessels was lower in the molecular layer, and the lowest number of vessels was observed in the cerebellar nuclei corresponding with their low volume. Nevertheless, the nuclei had the greatest density of blood vessels. The reduction of cerebellum volume in the Lurcher mice was accompanied by a reduction in vascularization in the individual cerebellar components, mainly in the cortex. Moreover, despite the lower density of microvessels in the Lurcher mice compared with the wild type mice, the relative density of microvessels in the cerebellar cortex and nuclei was greater in Lurcher mice. The complete primary morphometric data, in the form of continuous variables, is included as a supplement. Mapping of the cerebellar and midbrain microvessels has explanatory potential for studies using mouse models of neurodegeneration.
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Affiliation(s)
- Yaroslav Kolinko
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague Pilsen, Czech Republic
| | - Jan Cendelin
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague Pilsen, Czech Republic
| | - Milena Kralickova
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague Pilsen, Czech Republic
| | - Zbynek Tonar
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague Pilsen, Czech Republic
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Abstract
The name of Jan Evangelista Purkyně and the cerebellum belong inseparably together. He was the first who saw and described the largest nerve cells in the brain, de facto in the cerebellum. The most distinguished researchers of the nervous system then showed him the highest recognition by naming these neurons as Purkinje cells. Through experiments by J. E. Purkyně and his followers properly functionally was attributed to the cerebellum share in precision of motor skills. Despite ongoing and fruitful research, after a relatively long time, especially in the last two decades, scientists had to constantly replenish and re-evaluate the traditional conception of the cerebellum and formulate a new one. It started in the early 1990s, when it was found that cerebellar cortex contains more neurons than the cerebral cortex. Shortly thereafter it was gradually revealed that such enormous numbers of neural cells are not without an impact on brain functions and that the cerebellum, except its traditional role in the motor skills, also participates in higher nervous activity. These new findings were obtained thanks to the introduction of modern methods of examination into the clinical praxis, and experimental procedures using animal models of cerebellar disorders described below.
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Affiliation(s)
- F Vožeh
- Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.
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Cendelin J. From mice to men: lessons from mutant ataxic mice. CEREBELLUM & ATAXIAS 2014; 1:4. [PMID: 26331028 PMCID: PMC4549131 DOI: 10.1186/2053-8871-1-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 04/21/2014] [Indexed: 01/01/2023]
Abstract
Ataxic mutant mice can be used to represent models of cerebellar degenerative disorders. They serve for investigation of cerebellar function, pathogenesis of degenerative processes as well as of therapeutic approaches. Lurcher, Hot-foot, Purkinje cell degeneration, Nervous, Staggerer, Weaver, Reeler, and Scrambler mouse models and mouse models of SCA1, SCA2, SCA3, SCA6, SCA7, SCA23, DRPLA, Niemann-Pick disease and Friedreich ataxia are reviewed with special regard to cerebellar pathology, pathogenesis, functional changes and possible therapeutic influences, if any. Finally, benefits and limitations of mouse models are discussed.
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Affiliation(s)
- Jan Cendelin
- Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University in Prague, Lidicka 1, 301 66 Plzen, Czech Republic ; Biomedical Centre, Faculty of Medicine in Pilsen, Charles University in Prague, Plzen, Czech Republic
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Ji J, Hassler ML, Shimobayashi E, Paka N, Streit R, Kapfhammer JP. Increased protein kinase C gamma activity induces Purkinje cell pathology in a mouse model of spinocerebellar ataxia 14. Neurobiol Dis 2014; 70:1-11. [PMID: 24937631 DOI: 10.1016/j.nbd.2014.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 06/02/2014] [Accepted: 06/07/2014] [Indexed: 12/27/2022] Open
Abstract
Spinocerebellar ataxias (SCAs) are hereditary diseases leading to Purkinje cell degeneration and cerebellar dysfunction. Most forms of SCA are caused by expansion of CAG repeats similar to other polyglutamine disorders such as Huntington's disease. In contrast, in the autosomal dominant SCA-14 the disease is caused by mutations in the protein kinase C gamma (PKCγ) gene which is a well characterized signaling molecule in cerebellar Purkinje cells. The study of SCA-14, therefore, offers the unique opportunity to reveal the molecular and pathological mechanism eventually leading to Purkinje cell dysfunction and degeneration. We have created a mouse model of SCA-14 in which PKCγ protein with a mutation found in SCA-14 is specifically expressed in cerebellar Purkinje cells. We find that in mice expressing the mutated PKCγ protein the morphology of Purkinje cells in cerebellar slice cultures is drastically altered and mimics closely the morphology seen after pharmacological PKC activation. Similar morphological abnormalities were seen in localized areas of the cerebellum of juvenile transgenic mice in vivo. In adult transgenic mice there is evidence for some localized loss of Purkinje cells but there is no overall cerebellar atrophy. Transgenic mice show a mild cerebellar ataxia revealed by testing on the rotarod and on the walking beam. Our findings provide evidence for both an increased PKCγ activity in Purkinje cells in vivo and for pathological changes typical for cerebellar disease thus linking the increased and dysregulated activity of PKCγ tightly to the development of cerebellar disease in SCA-14 and possibly also in other forms of SCA.
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Affiliation(s)
- Jingmin Ji
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland
| | - Melanie L Hassler
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland
| | - Etsuko Shimobayashi
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland
| | - Nagendher Paka
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland
| | - Raphael Streit
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland
| | - Josef P Kapfhammer
- Anatomical Institute, Department of Biomedicine Basel, University of Basel, Pestalozzistr, 20, CH-4056 Basel, Switzerland.
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Changes in the Distribution of the α 3 Na(+)/K(+) ATPase Subunit in Heterozygous Lurcher Purkinje Cells as a Genetic Model of Chronic Depolarization during Development. Int J Cell Biol 2014; 2014:152645. [PMID: 24719618 PMCID: PMC3955620 DOI: 10.1155/2014/152645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/28/2013] [Accepted: 01/13/2014] [Indexed: 11/30/2022] Open
Abstract
A common assumption of excitotoxic mechanisms in the nervous system is that the ionic imbalance resulting from overstimulation of glutamate receptors and increased Na+ and Ca++ influx overwhelms cellular energy metabolic systems leading to cell death. The goal of this study was to examine how a chronic Na+ channel leak current in developing Purkinje cells in the heterozygous Lurcher mutant (+/Lc) affects the expression and distribution of the α3 subunit of the Na+/K+ ATPase pump, a key component of the homeostasis system that maintains ionic equilibrium in neurons. The expression pattern of the catalytic α3 Na+/K+ ATPase subunit was analyzed by immunohistochemistry, histochemistry, and Western Blots in wild type (WT) and +/Lc cerebella at postnatal days P10, P15, and P25 to determine if there are changes in the distribution of active Na+/K+ ATPase subunits in degenerating Purkinje cells. The results suggest that the expression of the catalytic α3 subunit is altered in chronically depolarized +/Lc Purkinje cells, although the density of active Na+/K+ ATPase pumps is not significantly altered compared with WT in the cerebellar cortex at P15, and then declines from P15 to P25 in the +/Lc cerebellum as the +/Lc Purkinje cells degenerate.
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