scholarly journals The Spatial Organization of the Intranuclear Structures of Human Brain Dopaminergic Neurons

Acta Naturae ◽  
2017 ◽  
Vol 9 (3) ◽  
pp. 81-88 ◽  
Author(s):  
D. E. Korzhevskii ◽  
V. V. Gusel’nikova ◽  
O. V. Kirik ◽  
E. G. Sukhorukova ◽  
I. P. Grigorev
Keyword(s):  
Substantia Nigra ◽  
Dopaminergic Neurons ◽  
Spatial Organization ◽  
Molecular Mechanisms ◽  
Three Dimensional ◽  
Selective Vulnerability ◽  
Confocal Laser ◽  
Double Labeling ◽  
Dimensional Reconstruction ◽  
Marinesco Bodies

We studied the intranuclear localization of protein nucleophosmin (B23) and ubiquitin in the dopaminergic neurons of human substantia nigra (n = 6, age of 25-87 years) using immunohistochemistry and confocal laser microscopy. Intranuclear ubiquitin-immunopositive bodies that morphologically correspond to Marinesco bodies were found to be present in substantia nigra dopaminergic (tyrosine hydroxylase-immunopositive) neurons but absent in non-dopaminergic neurons. The number of bodies varied from 0 to 6 per cell nucleus. Nucleophosmin (B23) was found in the neuronal nucleolus, with the nucleolus size being constant in the nigral neurons of each individual brain. All the observed neurons had only one large nucleolus with intense nucleophosmin immunoreactivity and a lightly stained region (1-2 m in diameter) that apparently represents the giant fibrillar center (GFC). An intensely immunostained nucleophosmin-containing granule was often observed at the GFC periphery. Double labeling demonstrated that nucleophosmin-immunoreactive nucleolus and ubiquitin-immunoreactive Marinesco bodies can occur both closely to and remotely from each other. Three-dimensional reconstruction indicates that rounded Marinesco bodies are polymorphic and often have a complex shape, with some flattening and concavities, which may be associated with contact not only with the nucleolus, but also, presumably, with other intranuclear structures free of ubiquitin or nucleophosmin. Ubiquitin-immunoreactive structures with a relatively small size (up to 1 m in length) and various clastosome-like shapes (Lafarga et al., 2002) often occur near Marinesco bodies. There were no cases of detection of ubiquitin in the nucleoli of dopaminergic neurons and nucleophosmin/B23 in typical Marinesco bodies. The obtained information may be helpful in unraveling the molecular mechanisms of the selective vulnerability of substantia nigra dopaminergic neurons to damaging factors.

scholarly journals Three-dimensional reconstruction of substantia nigra pars compacta of human brain

2018 ◽  
Vol 26 (2) ◽  
pp. 175-183
Author(s):  
Dmitriy N. Voronkov ◽  
Vladimir N. Salkov ◽  
Rudolf M. Khudoerkov
Keyword(s):  
Tyrosine Hydroxylase ◽  
Substantia Nigra ◽  
Human Brain ◽  
Spatial Organization ◽  
Three Dimensional ◽  
Spatial Differentiation ◽  
Dopamine Neurons ◽  
Immunohistochemical Method ◽  
Substantia Nigra Pars Compacta ◽  
Dimensional Reconstruction

Background. Up to the moment there is no universally accepted scheme of spatial organization of the groups of neurons of substantia nigra pars compacta of the human midbrain. A detailed study of the architectonics of this structure is necessary for pathomorphological analysis of agerelated changes in the nervous tissue and the associated neurodegenerative diseases with selective death of dopamine neurons. Aim. To clarify the peculiarities of the morphochemical organization of the substantia nigra (SN) of a human brain and to create a threedimensional model of pars compacta. Materials and Methods. Threedimensional reconstruction of substantia nigra pars compacta was performed on the brain autopsy material of individuals without neurological pathology (n=10, between 52 to 84 years of age) using a method of computed morphometry. Sections of the midbrain were stained by Nissl method and by an immunohistochemical method for localization of tyrosine hydroxylase – a marker of dopamine. Results. In the SN pars compacta accumulations of neurons were identified in the form of 9 bands oriented in the rostrocaudal direction and including four areas: medial, lateral, dorsal and ventral. Morphometric analysis detected significant differences in the density of neurons and in expression of tyrosine hydroxylase between the areas of SN. Conclusion. A model of cellular organization of SN pars compacta proposed by us on the basis of threedimensional reconstruction is characterized by a high degree of detalization as compared to similar works, and shows expressed spatial differentiation of the groups of neurons of SN which should be taken into consideration in pathomorphological examinations.

scholarly journals Earliest Mechanisms of Dopaminergic Neurons Sufferance in a Novel Slow Progressing Ex Vivo Model of Parkinson Disease in Rat Organotypic Cultures of Substantia Nigra

2019 ◽  
Vol 20 (9) ◽  
pp. 2224 ◽  
Author(s):  
Matteo Dal Ben ◽  
Rosario Bongiovanni ◽  
Simone Tuniz ◽  
Emanuela Fioriti ◽  
Claudio Tiribelli ◽  
...  
Keyword(s):  
Substantia Nigra ◽  
Parkinson Disease ◽  
Dopaminergic Neurons ◽  
Molecular Mechanisms ◽  
Ex Vivo ◽  
Ex Vivo Model ◽  
Redox Imbalance ◽  
Clinical Phase ◽  
Protein Clearance ◽  
Persistent Inflammation

The current treatments of Parkinson disease (PD) are ineffective mainly due to the poor understanding of the early events causing the decline of dopaminergic neurons (DOPAn). To overcome this problem, slow progressively degenerating models of PD allowing the study of the pre-clinical phase are crucial. We recreated in a short ex vivo time scale (96 h) all the features of human PD (needing dozens of years) by challenging organotypic culture of rat substantia nigra with low doses of rotenone. Thus, taking advantage of the existent knowledge, the model was used to perform a time-dependent comparative study of the principal possible causative molecular mechanisms undergoing DOPAn demise. Alteration in the redox state and inflammation started at 3 h, preceding the reduction in DOPAn number (pre-diagnosis phase). The number of DOPAn declined to levels compatible with diagnosis only at 12 h. The decline was accompanied by a persistent inflammation and redox imbalance. Significant microglia activation, apoptosis, a reduction in dopamine vesicle transporters, and the ubiquitination of misfolded protein clearance pathways were late (96 h, consequential) events. The work suggests inflammation and redox imbalance as simultaneous early mechanisms undergoing DOPAn sufferance, to be targeted for a causative treatment aimed to stop/delay PD.

scholarly journals Dendritic Spines and Development: Towards a Unifying Model of Spinogenesis—A Present Day Review of Cajal's Histological Slides and Drawings

2010 ◽  
Vol 2010 ◽  
pp. 1-29 ◽  
Author(s):  
Pablo García-López ◽  
Virginia García-Marín ◽  
Miguel Freire
Keyword(s):  
Central Nervous System ◽  
Dendritic Spines ◽  
Neural Activity ◽  
Molecular Mechanisms ◽  
Three Dimensional ◽  
Practical Interest ◽  
High Quality ◽  
Spine Development ◽  
Dimensional Reconstruction ◽  
The Central Nervous System

Dendritic spines receive the majority of excitatory connections in the central nervous system, and, thus, they are key structures in the regulation of neural activity. Hence, the cellular and molecular mechanisms underlying their generation and plasticity, both during development and in adulthood, are a matter of fundamental and practical interest. Indeed, a better understanding of these mechanisms should provide clues to the development of novel clinical therapies. Here, we present original results obtained from high-quality images of Cajal's histological preparations, stored at the Cajal Museum (Instituto Cajal, CSIC), obtained using extended focus imaging, three-dimensional reconstruction, and rendering. Based on the data available in the literature regarding the formation of dendritic spines during development and our results, we propose a unifying model for dendritic spine development.

Three-dimensional structure analysis of melanocytes and keratinocytes in senile lentigo

Microscopy ◽  
2020 ◽  
Author(s):  
Yuki Mizutani ◽  
Mika Yamashita ◽  
Rie Hashimoto ◽  
Toru Atsugi ◽  
Akemi Ryu ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Normal Skin ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Confocal Laser ◽  
Scanning Electron Micrographs ◽  
Large Numbers ◽  
Dimensional Reconstruction

Abstract Senile lentigo or age spots are hyperpigmented macules of skin that commonly develop following long-term exposure to ultraviolet radiation. This condition is caused by accumulation of large numbers of melanosomes (melanin granules) produced by melanocytes within neighboring keratinocytes. However, there is still no consensus regarding the melanosome transfer mechanism in senile lentigo. To date, most pathohistological studies of skin have been two-dimensional and do not provide detailed data on the complex interactions of the melanocyte–keratinocyte network involved in melanosome transfer. We performed a three-dimensional reconstruction of the epidermal microstructure in senile lentigo using three different microscopic modalities to visualize the topological melanocyte–keratinocyte relationship and melanosome distribution. Confocal laser microscopy images showed that melanocyte dendritic processes are more frequently branched and elongated in senile lentigo skin than in normal skin. Serial transmission electron micrographs showed that dendritic processes extend into intercellular spaces between keratinocytes. Focused ion beam-scanning electron micrographs showed that dendritic processes in senile lentigo encircle adjacent keratinocytes and accumulate large numbers of melanosomes. Moreover, melanosomes transferred to keratinocytes are present not only in the supranuclear area but throughout the perinuclear area except on the basal side. The use of these different microscopic methods helped to elucidate the three-dimensional morphology and topology of melanocytes and keratinocytes in senile lentigo. We show that the localization of melanosomes in dendritic processes to the region encircling recipient keratinocytes contributes to efficient melanosome transfer in senile lentigo.

Application of Phase Correlation to the Montage Synthesis and Three-Dimensional Reconstruction of Large Tissue Volumes from Confocal Laser Scanning Microscopy

2006 ◽  
Vol 12 (2) ◽  
pp. 106-112 ◽  
Author(s):  
Mohamed-Adel Slamani ◽  
Andrzej Krol ◽  
Jacques Beaumont ◽  
Robert L. Price ◽  
Ioana L. Coman ◽  
...  
Keyword(s):  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Phase Correlation ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser ◽  
Dimensional Reconstruction ◽  
3D Volume

We have implemented and tested a new automatic method for the montage synthesis and three-dimensional (3D) reconstruction of large tissue volumes from confocal laser scanning microscopy data (CLSM). This method relies on maximization of the phase correlation between adjacent images. It was tested on a large specimen (a murine heart) that was cut into a number of individual sections with thickness appropriate for CLSM. The sections were scanned horizontally (in-plane) and vertically (perpendicular to the optical planes) to produce “tiles” of a 3D volume. Phase correlation maximization was applied to the montage synthesis of in-plane tiles and 3D alignment of optical slices within a given physical section. The performance of the new method is evaluated.

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