The Second Hospital of Shandong University

JOURNAL/nrgr/04.03/01300535-202606000-00064/figure1/v/2026-02-11T151048Z/r/image-tiff Ferroptosis, a type of cell death that mainly involves iron metabolism imbalance and lipid peroxidation, is strongly correlated with the phagocytic response caused by bleeding after spinal cord injury. Thus, in this study, bulk RNA sequencing data (GSE47681 and GSE5296) and single-cell RNA sequencing data (GSE162610) were acquired from gene expression databases. We then conducted differential analysis and immune infiltration analysis. Atf3 and Piezo1 were identified as key ferroptosis genes through random forest and least absolute shrinkage and selection operator algorithms. Further analysis of single-cell RNA sequencing data revealed a close relationship between ferroptosis and cell types such as macrophages/microglia and their intrinsic state transition processes. Differences in transcription factor regulation and intercellular communication networks were found in ferroptosis-related cells, confirming the high expression of Atf3 and Piezo1 in these cells. Molecular docking analysis confirmed that the proteins encoded by these genes can bind cycloheximide. In a mouse model of T8 spinal cord injury, low-dose cycloheximide treatment was found to improve neurological function, decrease levels of the pro-inflammatory cytokine inducible nitric oxide synthase, and increase levels of the anti-inflammatory cytokine arginase 1. Correspondingly, the expression of the ferroptosis-related gene Gpx4 increased in macrophages/microglia, while the expression of Acsl4 decreased. Our findings reveal the important role of ferroptosis in the treatment of spinal cord injury, identify the key cell types and genes involved in ferroptosis after spinal cord injury, and validate the efficacy of potential drug therapies, pointing to new directions in the treatment of spinal cord injury.

Spinal cord injury (SCI) repair lacks clinically validated restorative therapies. Transplantation of exogenous neural stem cells (NSCs) offers significant potential for therapeutic applications; however, challenges remain, including substantial cell loss, uncontrolled differentiation, and limited tissue integration within inflammatory microenvironments. Furthermore, the workflow associated with traditional NSC transplantation-including cryopreservation, thawing, transportation, and injection-remains fragmented, resulting in systemic limitations. These issues manifest as reduced cell viability and stemness, an elevated risk of contamination, and dosing inaccuracies. All these significantly impede clinical translation. An integrated system for NSC preservation, transport, and transplantation is required to meet the following criteria: (i) maintenance of high cell viability and stemness post-cryopreservation and thawing; (ii) modulation of the acute-phase immune microenvironment; (iii) regulation of the differentiation fate of transplanted NSCs; (iv) injectable, standardized, and closed-system operation. To meet these requirements, we established a comprehensive cryopreservation, thawing, and transplant (CTT) integrated platform. Utilizing the bioactive material PM-BMH@Exo, this platform enables seamless end-to-end workflow integration through a mechanism that preserves bioactivity. It not only ensures high viability retention and directed differentiation of NSCs but also effectively mitigates the rapid viability decline of cells observed after traditional cryopreservation. Furthermore, the system enables closed-loop operations spanning cryopreservation, thawing, and minimally invasive injection. It breaks through systemic bottlenecks from multi-step procedures, comprehensively enhancing the timeliness and standardization of therapeutic interventions. We systematically evaluated the system's feasibility and efficacy via in vitro and in vivo experiments. This study presents a technologically viable and clinically compatible pathway with potential applications for SCI repair.

Neural stem cells (NSCs) transplantation offers a promising therapeutic approach for spinal cord injury (SCI), addressing the challenge of neuron irreparability. However, the uncontrolled differentiation of transplanted NSCs and the inflammatory environment at the injury site limit the efficacy of cell-based treatments. To overcome these obstacles, simultaneously regulating NSCs differentiation and reshaping immune microenvironment is vital for enhancing the effectiveness of cell therapy. In this study, we proposed calcium phytate nanoparticles (Ca-PA NPs) as synergistic regulators capable of promoting neuronal differentiation and regulating the polarization of immune cells. This approach leverages the coordination properties of calcium ions and phytic acid, as well as the decomposition characteristics of calcium phytate. The nanoparticles can be endocytosed by NSCs or microglia, and decomposed in their lysosomes, forming the intracellular small molecule/ion storms. In vitro, NSCs endocytosing Ca-PA NPs predominantly differentiate into neurons, while microglia internalizing the nanoparticles transition from a pro-inflammatory M1 phenotype to a neuroprotective M2 phenotype. Importantly, the animal experiments proved that Ca-PA NPs significantly enhanced functional recovery in SCI mice by synergistically promoting neuronal differentiation of transplanted NSCs and reshaping immuno-microenvironment. These findings open a new route to design nano-regulators for immune microenvironment involved stem cell therapy of SCI.