Inflammatory reactions are recognized as pivotal in spinal cord injury (SCI), with the anti-inflammatory role of polarized microglia crucial in mitigating such injury. The present study aimed to determine the protective effects of GsMTx4 on functional recovery in a mouse model of SCI and investigate the role of GsMTx4 in cytokine-induced microglial activation and associated molecular mechanisms.

We assessed the effects of GsMTx4 on motor function in a mouse model of SCI, including neuronal survival and activated microglia in the vicinity of the injury after SCI. We also investigated the effects of GsMTx4 on expression of relevant inflammatory factors involved in cytokine-induced microglial activation and the associated signaling pathways.

GsMTx4 effectively promoted functional recovery in mice and alleviated nerve damage after SCI. Additionally, GsMTx4 facilitated the transition of microglia from the M1 phenotype to the M2 phenotype, suppressed microglial activation, and reduced the expression of corresponding inflammatory mediators. These effects may involve modulation of neurogenic inflammation through the Piezo1/NFκB/STAT6 pathway, at least in part.

GsMTx4 safeguards against SCI by regulating microglial polarization, potentially via the Piezo1/NFκB/STAT6 pathway, offering initial evidence supporting the potential therapeutic efficacy of GsMTx4 for treatment of SCI.

To investigate the distribution and function of olfactory ensheathing cells (OECs) following lumbar puncture (LP) transplantation in mouse spinal cord injury (SCI).

OECs were transplanted by LP at level L3-5, 1 week after transected SCI at T8 vertebra. Mice were killed at 3, 21, and 56 days after LP transplantation, and the relative distribution of cells at T8 vertebra was quantitated. The injured spine was also tested by immunohistochemistry to assess neuron regeneration and scar bridging at 8 weeks posttransplantation. Motor functions of mice were evaluated during the observation period using the Basso Mouse Scale.

OECs were examined and confirmed by studying cell morphology under phase contrast and immunostaining of NGFR p75. LP-transplanted OECs could be detected just 3 days after transplantation (p75⁺ area: 0.16 mm²) and accumulated to 0.31 and 0.30 mm² at 21 and 56 days postengraftment, respectively. The number of endogenous neurons, −400 to +400 µm, far from the epicenter, in OEC-transplanted mice was more than that in SCI mice without engraftment. SCI lesion of mice in the control group (164.3±3.97 µm) was much longer than that in OEC-grafted group (116.7±3.60 µm). Grafts of OECs induced significant functional improvement in mice that underwent T8 vertebral transection, just from 3 days after cell injection.

LP is a minimally invasive method for OEC transplantation to treat SCI. This is the first study to visualize the distribution and functions of LP-transplanted OECs in the intact and injured spinal cord.