Requirement for Dicer in Maintenance of Monosynaptic Sensory-Motor Circuits in the Spinal Cord

Abstract Introduction Spinal cord injuries (SCIs) represent a severe neuro-traumatic occurrence and an excruciating social burden. Though the hyperbaric oxygen (HBO2) has been credited as a first line therapeutic resource for SCIs, its mechanism of action in the spine is only partially known, while the impingement upon other areas of the nervous system deserves additional investigation. In this study we deem to describe a novel effect of HBO2 in a subject affected by SCI who, along with the clinical improvement, showed a reshaped connectivity in cortical sensory-motor areas. Case presentation A 45 years male presenting severe sensory-motor symptoms following a spinal lesion partially involving the C1 segment was successfully treated with HBO2 cycles. After the dramatic improvement reflected by an excellent optimization of the single performances, it has been investigated whether this result would reveal not only an intrinsic effect upon the spinal cord, but also a better connectivity strength in sensory-motor cortical regions. The results obtained by implementing EEG recordings with EEGLAB auto regressive vector plugins indeed suggest a substantial reshaping of cortico-cortical connectivity after HBO2. Discussion These results show a correlation between positive clinical evolution and a new modulation of cortical connectivity. Though further clinical investigations would clarify as to whether HBO2 might be directly or epiphenomenally involved in this aspect of the network architecture, our report suggests that a comparison between clinical results and the study of brain connectivity represent a holistic approach in investigating the physiopathology of SCIs and in monitoring the treatment.

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Positional Strategies for Connection Specificity and Synaptic Organization in Spinal Sensory-Motor Circuits

Neuron ◽

10.1016/j.neuron.2019.04.008 ◽

2019 ◽

Vol 102 (6) ◽

pp. 1143-1156.e4 ◽

Cited By ~ 18

Author(s):

Nikolaos Balaskas ◽

L.F. Abbott ◽

Thomas M. Jessell ◽

David Ng

Keyword(s):

Synaptic Organization ◽

Motor Circuits ◽

Sensory Motor

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PROJECTION OF THE SENSORY MOTOR CORTEX TO THE THALAMUS, THE DORSAL COLUMN NUCLEUS, THE TRIGEMINAL NUCLEUS AND THE SPINAL CORD IN THE CAT.*

Psychiatry and Clinical Neurosciences ◽

10.1111/j.1440-1819.1964.tb00028.x ◽

1964 ◽

Vol 18 (4) ◽

pp. 337-338 ◽

Cited By ~ 3

Author(s):

Etsuro Kawana ◽

Toshio Kusama

Keyword(s):

Spinal Cord ◽

Motor Cortex ◽

Dorsal Column ◽

Trigeminal Nucleus ◽

Sensory Motor

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Vasoactive intestinal polypeptide excitation of central neurons

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y78-052 ◽

1978 ◽

Vol 56 (2) ◽

pp. 337-340 ◽

Cited By ~ 104

Author(s):

J. W. Phillis ◽

J. R. Kirkpatrick ◽

S. I. Said

Keyword(s):

Spinal Cord ◽

Cerebral Cortex ◽

Substance P ◽

Vasoactive Intestinal Polypeptide ◽

Cortical Neurons ◽

Dorsal Root ◽

Central Neurons ◽

Sensory Motor ◽

Repeated Applications ◽

Intestinal Polypeptide

Vasoactive intestinal polypeptide (VIP) was tested on neurons in the rat sensory motor cerebral cortex and on the isolated hemisected toad spinal cord. Iontophoretically applied VIP excited deep, spontaneously active cortical neurons, including identified corticospinal neurons. The excitation had a latency of onset varying from several seconds to over 1 min and often lasted for a minute or longer after cessation of the application. Desensitization of the effect occurred with repeated applications. VIP caused a depolarization of motoneurons and dorsal root terminals in the isolated amphibian spinal cord. Threshold for this effect was about 10−6 M. The effects of VIP on both preparations were comparable with those of another peptide, substance P.

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Functional and Anatomical Reorganization of the Sensory-Motor Cortex after Incomplete Spinal Cord Injury in Adult Rats

Journal of Neuroscience ◽

10.1523/jneurosci.1828-09.2009 ◽

2009 ◽

Vol 29 (39) ◽

pp. 12210-12219 ◽

Cited By ~ 111

Author(s):

A. Ghosh ◽

E. Sydekum ◽

F. Haiss ◽

S. Peduzzi ◽

B. Zorner ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Motor Cortex ◽

Incomplete Spinal Cord Injury ◽

Adult Rats ◽

Cord Injury ◽

Sensory Motor

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Groucho/TLE opposes axial to hypaxial motor neuron development

10.1101/2020.03.10.986323 ◽

2020 ◽

Author(s):

Adèle Salin-Cantegrel ◽

Rola Dali ◽

Jae Woong Wang ◽

Marielle Beaulieu ◽

Mira Deshmukh ◽

...

Keyword(s):

Spinal Cord ◽

Motor Neuron ◽

Motor Neurons ◽

Molecular Mechanisms ◽

List Type ◽

Neuron Development ◽

In Ovo ◽

Motor Circuits ◽

Axial Muscles ◽

Muscle Innervation

ABSTRACTSpinal cord motor neuron diversity and the ensuing variety of motor circuits allow for the processing of elaborate muscular behaviours such as body posture and breathing. Little is known, however, about the molecular mechanisms behind the specification of axial and hypaxial motor neurons controlling postural and respiratory functions respectively. Here we show that the Groucho/TLE (TLE) transcriptional corepressor is a multi-step regulator of axial and hypaxial motor neuron diversification in the developing spinal cord. TLE first promotes axial motor neuron specification at the expense of hypaxial identity by cooperating with non-canonical WNT5A signalling within the motor neuron progenitor domain. TLE further acts during post-mitotic motor neuron diversification to promote axial motor neuron topology and axonal connectivity whilst suppressing hypaxial traits. These findings provide evidence for essential and sequential roles of TLE in the spatial and temporal coordination of events regulating the development of motor neurons influencing posture and controlling respiration.HIGHLIGHTSGroucho/TLE mediates non-canonical WNT signalling in developing motor neuronsNon canonical WNT:TLE pathway regulates thoracic motor neuron diversificationTLE promotes axial while inhibiting hypaxial motor neuron developmentTLE influences developing motor neuron topology and muscle innervationIN BRIEFSalin-Cantegrel et al use in ovo engineered approaches to show that a non-canonical WNT:TLE pathway coordinates temporally and spatially separated elements of motor neuron diversification, repressing hypaxial motor neuron development to promote the axial fate.GRAPHICAL ABSTRACTTLE contribution to the development of thoracic somatic motor columnsProgenitor cells in the ventral pMN domain are exposed to higher concentrations of non-canonical WNTs and express more TLE. Cooperation of non-canonical WNTs and TLE renders ventral pMN progenitors refractory to a respiratory MN fate, thereby contributing to the separation of MMC and RMC MN lineages. Differentiating MNs that maintain high TLE expression also maintain LHX3 expression, adopt axial motor neuron topology and connect to axial muscles. TLE activity in differentiating MMC MNs prevents the acquisition of respiratory MN topology and innervation traits.

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Edouard Long. The central pathways of general sensitivity (anatomo-clinical study). Paris. 1899

Neurology Bulletin ◽

10.17816/nb51059 ◽

2020 ◽

Vol VIII (1) ◽

pp. 217-220

Author(s):

G. Troshin

Keyword(s):

Spinal Cord ◽

Clinical Study ◽

Brain Stem ◽

Large Brain ◽

Sensory Motor ◽

Motor Region ◽

Order Of Presentation

In the first part of his work, the author gives a literary survey of the question of the central conductors of general sensitivity. The order of presentation is as follows: sensitive pathways of the spinal cord, brain stem, large brain (from thalamus opticus to the cortex); at the end, the author examines the arguments in favor of one or another localization of the sensory motor region in the cortex.

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