Visualization of Electrophysiological Activity in the Spinal Cord Using Magnetospinography

Tethered cord syndrome (TCS) is a stretch-induced functional disorder of the spinal cord. The mechanical cause of TCS is an inelastic structure anchoring the caudal end of the spinal cord that prevents cephalad movement of the lumbosacral cord. Stretching of the spinal cord occurs in patients either when the spinal column grows faster than the spinal cord or when the spinal cord undergoes forcible flexion and extension. Research in patients and experimental animals suggests that there is a link between the clinical dysfunctions that characterize TCS and putative pathophysiological changes that accompany this syndrome. Among these changes are depression of electrophysiological activity and shifts in the reduction/oxidation ratio of cytochrome oxidase. The latter suggests that there is impairment of oxidative metabolism. These putative pathophysiological changes in TCS occur mainly within the lumbosacral cord under excessive tension. The authors discuss the pathophysiology of TCS and examine related symptoms.

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Role of human induced pluripotent stem cell-derived spinal cord astrocytes in the functional maturation of motor neurons in a multielectrode array system

10.1101/614297 ◽

2019 ◽

Author(s):

Arens Taga ◽

Raha Dastgheyb ◽

Christa Habela ◽

Jessica Joseph ◽

Jean-Philippe Richard ◽

...

Keyword(s):

Spinal Cord ◽

Stem Cell ◽

Motor Neurons ◽

Pluripotent Stem Cell ◽

Induced Pluripotent Stem Cell ◽

Time Dependent ◽

Multielectrode Array ◽

Electrophysiological Activity ◽

Induced Pluripotent

AbstractThe ability to generate human induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system (CNS) biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a multielectrode array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-As are co-cultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to co-culture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron cross-talk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and co-culture with neurons influences astrocyte maturation as well. Taken together these data indicate that in a human in vitro spinal cord culture system, astrocytes alter hiPSC-MN maturation in a time-dependent and species specific manner and suggest a closer approximation of in vivo conditions.Main PointsWe developed a method for the co-culture of human iPSC-A/MN for multielectrode array recordings.The morphological, molecular, pharmacological, and electrophysiological characterization of the co-cultures suggests bidirectional maturation.

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Visualization of electrophysiological activity in the cervical spinal cord using magnetospinography

Journal of the Neurological Sciences ◽

10.1016/j.jns.2019.10.1494 ◽

2019 ◽

Vol 405 ◽

pp. 349-350

Author(s):

S. Sumiya ◽

S. Kawabata ◽

S. Ushio ◽

T. Sasaki ◽

J. Hashimoto ◽

...

Keyword(s):

Spinal Cord ◽

Cervical Spinal Cord ◽

Electrophysiological Activity

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Epidural Spinal Electrogram Provides Direct Spinal Recordings in Awake Human Participants

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.721076 ◽

2021 ◽

Vol 15 ◽

Author(s):

John F. Burke ◽

Nikhita Kunwar ◽

Maria S. Yaroshinsky ◽

Kenneth H. Louie ◽

Prasad Shirvalkar ◽

...

Keyword(s):

Spinal Cord ◽

Human Subjects ◽

Movement Control ◽

Overground Walking ◽

Kinematic Data ◽

Human Spinal Cord ◽

Electrophysiological Activity ◽

Upper And Lower Extremities ◽

Novel Method ◽

Human Participants

Little is known about the electrophysiological activity of the spinal cord during voluntary movement control in humans. We present a novel method for recording electrophysiological activity from the human spinal cord using implanted epidural electrodes during naturalistic movements including overground walking. Spinal electrograms (SEGs) were recorded from epidural electrodes implanted as part of a test trial for patients with chronic pain undergoing evaluation for spinal cord stimulation. Externalized ends of the epidural leads were connected to an external amplifier to capture SEGs. Electromyographic and accelerometry data from the upper and lower extremities were collected using wireless sensors and synchronized to the SEG data. Patients were instructed to perform various arm and leg movements while SEG and kinematic data were collected. This study proves the safety and feasibility of performing epidural spinal recordings from human subjects performing movement tasks.

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