DOI: 10.5061/dryad.bnzs7h4qj
title: Data from: Time-dependent adaptations of damaged neurons and their microenvironment in the regenerating adult zebrafish spinal cord

description: Spinal cord injury (SCI) triggers complex cellular and extracellular
 responses that disrupt neuronal connectivity and hinder repair. While
 mammals have limited regenerative abilities, zebrafish achieve functional
 recovery through coordinated neuroprotection and plasticity. Here, we
 examined how structural and functional adaptations of damaged spinal
 neurons interact with extracellular matrix (ECM) dynamics during
 regeneration in adult zebrafish. We found that injured neurons undergo
 reversible changes in cellular properties and synaptic input, mediated
 mainly by glutamatergic signaling. These modifications coincide with a
 transient ECM reorganization marked by increased deposition of chondroitin
 sulfate proteoglycans (CSPGs). Enzymatic CSPG degradation paradoxically
 partially impaired long-term axonal regrowth and locomotor recovery. Thus,
 CSPG-rich ECM exerts a dual role: initially restricting plasticity but
 subsequently supporting structural stabilization and regeneration. Our
 findings highlight a temporally coordinated interplay between neuronal
 excitability, synaptic remodeling, and ECM reorganization as key
 determinants of spinal cord repair, offering mechanistic insights for
 enhancing nervous system regeneration.
description: # Data from: Time-dependent adaptations of damaged neurons and their
 microenvironment in the regenerating adult zebrafish spinal cord Dataset
 DOI: [10.5061/dryad.bnzs7h4qj](https://doi.org/10.5061/dryad.bnzs7h4qj) ##
 Description of the data and file structure #### File name: Dataset.xlsx
 The dataset contains all the data used to generate the statistical
 analyses (as presented in Table S1) and figure panels (in both main
 figures and supplementary figures) included in this manuscript. In detail:
 **Figure 1** Panel B: Soma sizes of different neuronal populations, such
 as all Motoneurons (MNs), primary Motoneurons (pMNs), all V2a Interneurons
 (V2a-INs), dorsal V2a Interneurons (dV2a-INs). Panel D: Number of
 dendritic intersections for different distances from the soma for both
 pMNs and dV2a-INs Panel G: Maximum rostral projection of the dendrites of
 the uninjured and injured pMNs. Panel H: Maximum rostral projection of the
 dendrites of the uninjured and injured dV2a-INs. Panel I: Soma sizes of
 the pMNs and dV2-INs in uninjured (control) and injured (7 days post
 injury; dpi) animals. **Figure 2** Panel B: Number of c-Fos positive
 neurons in uninjured (control) and injured (3 dpi) animals. Panel C:
 Proportion of c-Fos positive pMNs and dV2a-INs in uninjured (control) and
 injured (3 dpi) animals. Panel G: Adaptation Index for uninjured (control)
 and injured (3 dpi, 7 dpi, and 14 dpi) pMNs and dV2a-INs. **Figure 3**
 Panel A: Mean EPSP frequency and EPSP amplitude obtained from uninjured
 (control) and injured (3 dpi, 7 dpi, and 14 dpi) pMNs. Panel B: Mean EPSP
 frequency and EPSP amplitude obtained from uninjured (control) and injured
 (3 dpi, 7 dpi, and 14 dpi) dV2a-INs. Panel C: Mean EPSP frequency, mean
 EPSP amplitude, and resting membrane potential (RMP) obtained from injured
 (3dpi) pMNs in control (Saline) and after application of NBQX and APV.
 Panel D: Mean EPSP frequency, mean EPSP amplitude, and RMP obtained from
 injured (3dpi) dV2a-INs in control (Saline) and after application of NBQX
 and APV. Panel F: Proportion of the SV2 positive sites that are GFP
 positive (V2a-IN positive). Panel G: Number of perisomatic SV2-positive
 sites in uninjured (control) and injured (3 dpi, 7 dpi, and 14 dpi) pMNs.
 **Figure 4** Panel D: Normalized intensity of WFA staining in uninjured
 (control) and injured (3 dpi, 7 dpi and 14 dpi) animals. Panel E:
 Normalized intensity of WFA staining around the pMN somata obtained from
 uninjured (control) and injured (3 dpi, 7 dpi, and 14 dpi) animals. Panel
 F: Normalized intensity of WFA staining around the dV2a-INs somata
 obtained from uninjured (control) and injured (3 dpi, 7 dpi, and 14 dpi)
 animals. **Figure 5** Panel B: Normalized intensity of WFA staining in
 uninjured (control), injured (3 dpi), injured (3 dpi) with Vehicle, and
 injured (3 dpi) with ChABC animals. Panel C: Adaptation index, resting
 membrane potential (RMP), mean EPSP frequency, and mean EPSP amplitude
 obtained from injured (3dpi) and injured (3 dpi) with ChABC pMNs and
 dV2a-INs. Panel D: Number of SV2 positive terminals at 3 dpi, 7 dpi, and
 14 dpi in injured and injured with ChABC animals. Panel E: Regeneration
 index at 7 dpi, 14 dpi, and 21 dpi in injured with Vehicle and injured
 with ChABC animals. Bridging initiation at 7 dpi of the injured with
 Vehicle and injured with ChABC animals. Panel F: Normalized Tubulin
 intensity at 7 dpi, 14 dpi, and 21 dpi in injured with Vehicle and injured
 with ChABC animals. Panel G: Normalized GFP intensity at 7 dpi, 14 dpi,
 and 21 dpi in injured with Vehicle and injured with ChABC animals. Panel
 H: Total distance traveled and immobility index at 7 dpi, 14 dpi, and 21
 dpi in injured with Vehicle and injured with ChABC animals. Panel I: Total
 time of swimming at 7 dpi, 14 dpi, and 21 dpi in injured with Vehicle and
 injured with ChABC animals. **Figure S2** Panel A: Resting membrane
 potential (RMP), input resistance (Rinput), action potential threshold,
 action potential peak, action potential amplitude, action potential
 rheobase, action potential half-width duration, and
 after-hyperpolarization (AHP) amplitude in uninjured (control) and injured
 (3 dpi, 7 dpi, and 14 dpi) pMNs. Panel B: Resting membrane potential
 (RMP), input resistance (Rinput), action potential threshold, action
 potential peak, action potential amplitude, action potential rheobase,
 action potential half-width duration, and after-hyperpolarization (AHP)
 amplitude in uninjured (control) and injured (3 dpi, 7 dpi, and 14 dpi)
 dV2a-INs. **Figure S3** Panel A: Normalized WFA intensity vs. pMN or
 dV2a-IN soma size. **Figure S4** Panel A: Normalized intensity of WFA
 staining in uninjured (control), injured (3 dpi), injured (3 dpi) with
 4units of ChABC, and injured (3 dpi) with 8 units of ChABC animals.
 **Figure S5** Adaptation index, resting membrane potential (RMP), input
 resistance (Rinput), action potential rheobase, action potential
 amplitude, after hyperpolarization (AHP) amplitude, action potential
 half-width duration, action potential threshold, mean EPSP frequency, and
 mean EPSP amplitude of injured (3 dpi) and injured (3 dpi) with Vehicle.
 **Figure S6** Panel B: Total distance, number of turns, immobility index,
 mean acceleration, and percentage of activity of uninjured (control) and
 injured (3 dpi, 7 dpi, 14 dpi, and 21 dpi) animals that receive the
 Vehicle. Panel C: Total distance, number of turns, immobility index, mean
 acceleration, and percentage of activity of uninjured (control) and
 injured (3 dpi, 7 dpi, 14 dpi, and 21 dpi) animals that receive the ChABC.
 ## Code/software Any program that will open a spreadsheet, such as Excel
 is recommended. ## Access information Other publicly accessible locations
 of the data: * Not applicable Data was derived from the following sources:
 * Not applicable