Published online Feb 18, 2023. doi: 10.5312/wjo.v14.i2.64
Peer-review started: September 1, 2022
First decision: December 19, 2022
Revised: December 22, 2022
Accepted: February 2, 2023
Article in press: February 2, 2023
Published online: February 18, 2023
Processing time: 169 Days and 11.4 Hours
Globally, complete neurological recovery of spinal cord injury (SCI) is still less than 1%, and 90% experience permanent disability. The key issue is that a pharmacological neuroprotective-neuroregenerative agent and SCI regeneration mechanism have not been found. The secretomes of stem cell are an emerging neurotrophic agent, but the effect of human neural stem cells (HNSCs) secretome on SCI is still unclear.
HNSCs-secretome is expected to be the basis for use in SCI cases in the primary research stage, translational research, and neurological research for the benefit of managing SCI disease problems.
To investigate the effects of HNSCs-secretome and the regeneration mechanism on subacute SCI in rats.
An experimental study was conducted with 45 Rattus norvegicus, divided into 15 normal, 15 control (10 mL physiologic saline), and 15 treatment (30 μL HNSCs-secretome, intrathecal T10, three days post-traumatic). The strategies to increase the HNSCs-secretome production capacity include hypoxic preconditioning, tissue engineering, and growth medium composition. Locomotor function was evaluated weekly by blinded evaluators. Fifty-six days post-injury, specimens were collected, immunohistochemical-enzyme-linked immunosorbent assay assessment, and hematoxylin-eosin staining. We analyzed free radical oxidative stress (F2-Isoprostanes), nuclear factor-kappa B (NF-κB), matrix metallopeptidase 9 (MMP9), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), transforming growth factor-beta (TGF-β), vascular endothelial growth factor (VEGF), B cell lymphoma-2 (Bcl-2), nestin, brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and spinal cord lesion. The regeneration mechanism of SCI was analyzed using partial least squares structural equation modeling (PLS SEM).
The regeneration mechanism of SCI is valid by analyzed outer model, inner model, and hypothesis testing in PLS SEM, started with pro-inflammation followed by anti-inflammation, anti-apoptotic, neuroangiogenesis, neurogenesis, and locomotor function. HNSCs-secretome significantly improved locomotor recovery, reduced spinal cord lesion size, increased neurogenesis (nestin, BDNF, and GDNF), neuroangiogenesis (VEGF), anti-apoptotic (Bcl-2), anti-inflammatory (IL-10 and TGF-β), but decreased pro-inflammatory (NF-κB, MMP9, TNF-α), F2-Isoprostanes.
HNSCs-secretome as a potential agent for the treatment of SCI and uncover the SCI regeneration mechanism.
Future research investigating the chronic phase of SCI models may provide further evidence regarding the mechanism of SCI regeneration given HNSCs-secretome injection.