Project description:The human spinal cord contains diverse cell types, governed by a series of spatiotemporal events for tissue assembly and functions. However, the regulation of cell fate specification in the human developing spinal cord remains largely unknown. By performing single-cell and spatial multi-omics methods, we integrated the datasets and created a comprehensive human developmental atlas of the first trimester spinal cord. Unexpectedly, we discovered unique events in human spinal cord development, including early loss of active neural stem cells, simultaneous occurrence of neurogenesis and gliogenesis, and distinct spatiotemporal genetic regulations of fate choices. We also identified distinct regulations of cancer stem cells in ependymomas from our atlas. Thus, we demonstrate spatiotemporal genetic regulation of human spinal cord development and its potential to understand novel disease mechanisms.
Project description:The human spinal cord contains diverse cell types, governed by a series of spatiotemporal events for tissue assembly and functions. However, the regulation of cell fate specification in the human developing spinal cord remains largely unknown. By performing single-cell and spatial multi-omics methods, we integrated the datasets and created a comprehensive human developmental atlas of the first trimester spinal cord. Unexpectedly, we discovered unique events in human spinal cord development, including early loss of active neural stem cells, simultaneous occurrence of neurogenesis and gliogenesis, and distinct spatiotemporal genetic regulations of fate choices. We also identified distinct regulations of cancer stem cells in ependymomas from our atlas. Thus, we demonstrate spatiotemporal genetic regulation of human spinal cord development and its potential to understand novel disease mechanisms.
Project description:Electrical stimulation can augment or modify neuronal function and can have therapeutic benefits for certain neurological disorders. There is evidence that enhancing spinal excitability with either epidural or transcutaneous stimulation can restore some volitional motor output after spinal cord injury (SCI). Lumbosacral epidural stimulation temporarily improves locomotor and autonomic function in both rodents and humans with SCI. When combined with overground locomotor training enabled by a weight-supporting device, epidural electrical stimulation (EES) promotes extensive reorganization of residual neural pathways that improves locomotion after stopping stimulation. However, the exact mechanism underlying the reconstruction of spinal cord neural circuits with electrical stimulation is not yet known. Thus, we developed a epidural electrical and muscle stimulation(EEMS) system at the interface of the spinal cord and muscle to mimic feedforward and feedback electrical signals in spinal sensorimotor circuits. Using methods of motor function evaluation, neural circuit tracing and neural signal recording, we discovered a unique stimulus frequency of 10-20 Hz under EEMS conditions that was required for structural and functional reconstruction of spinal sensorimotor circuits. Single-cell transcriptome analysis of EEMS activated motoneurons characterized molecular networks involved in spinal sensorimotor circuit reconstruction. This study provides insights into neural signal decoding during spinal sensorimotor circuit reconstruction, and indicates a technological approach for the clinical treatment of SCI.
Project description:Adult zebrafish have the ability to recover from spinal cord injury and exhibit re-growth of descending axons from the brainstem to the spinal cord. We performed gene expression analysis using microarray to find damage-induced genes after spinal cord injury, which shows that Sox11b mRNA is up-regulated at 11 days after injury. However, the functional relevance of Sox11b for regeneration is not known. Here, we report that the up-regulation of Sox11b mRNA after spinal cord injury is mainly localized in ependymal cells lining the central canal and in newly differentiating neuronal precursors or immature neurons. Using an in vivo morpholino-based gene knockout approach, we demonstrate that Sox11b is essential for locomotor recovery after spinal cord injury. In the injured spinal cord, expression of the neural stem cell associated gene, Nestin, and the proneural gene Ascl1a (Mash1a), which are involved in the self-renewal and cell fate specification of endogenous neural stem cells, respectively, is regulated by Sox11b. Our data indicate that Sox11b promotes neuronal determination of endogenous stem cells and regenerative neurogenesis after spinal cord injury in the adult zebrafish. Enhancing Sox11b expression to promote proliferation and neurogenic determination of endogenous neural stem cells after injury may be a promising strategy in restorative therapy after spinal cord injury in mammals. Spinal cord injury or control sham injury was performed on adult zebrafish. After 4, 12, or 264 hrs, a 5 mm segment of spinal cord was dissected and processed (as a pool from 5 animals) in three replicate groups for each time point and treatment.
Project description:NSCs adhesion affinity along the AP axis is under the control of endogenous signalling molecular networks, the Wnt and RA signalling The caudal spinal cord domain expresses a high amount of ECM genes compare to rostral.
Project description:Transcriptome analysis of spinal cord microglia and total spinal cord from Lewis rats intratracheally treated with PBS, neomycin or vancomycin.