Experimental study of cBMMSC based on nanosilver hydrogel nerve conduit for repairing spinal cord injury

Abstract Investigating the role of cranial bone marrow mesenchymal stem cells (cBMMSC) based on nanosilver hydrogel nerve conduits in the repair of spinal cord injury. Thirty adult Wistar rats, male and female, with body mass of 210‐240 g, were selected as experimental animals and divided into control group and experimental group, 15 rats each, by random number table method. The experimental group was treated with spinal cord injury and localized transplantation of cBMMSC‐containing nanosilver hydrogel nerve conduits, while the control group was treated with spinal cord injury and localized transplantation of cBMMSC‐free nanosilver hydrogel nerve conduits. Four weeks after transplantation, the expression of neuron‐specific enolase (NSE) in rat anti‐human nuclear monoclonal antibody (MAB1281)‐positive cells was detected by immunostaining in spinal cord tissue sections of the two groups to assess the differentiation of cBMMSC to neuron‐like cells in the nerve conduits after transplantation; the number of BrdU‐positive cells was detected to assess the neuronal regeneration of the localized spinal cord injury of the two groups; and the length of axons was observed with laser Confocal photography was used to observe the length of axons; HE staining was used to observe the scarring and cavities in the spinal cord sections of the two groups; immunofluorescence was used to detect neuron‐like markers (Nestin, NSE, NF200, GFAP) in the two groups, and the OD values were determined by the Image Processing and Analysis System (IPAAS); and Western blot was used to detect the neurotransmitters of motor fibres, acetylcholinesterase (ChAT), sensory fibres, and sensory fibres, as well as the neurotransmission of motor fibres, acetylcholine production‐limiting enzyme (ChAT) and sensory fibre neurotransmitter glutamate synthase (GOGAT); motor function was assessed by BBB score; somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) were detected by body surface electrode assay in the two groups, and the neurophysiological recovery effect was evaluated. Four weeks after transplantation, the NSE content of MAB1281‐positive cells in the experimental group was significantly higher than that of the control group; the number of BrdU‐positive cells and axon length were significantly greater than that of the control group ( p < 0.05); the scarring and cavitation of spinal cord slices were significantly lighter than that of the control group; the expression levels of Nestin, NSE, NF200, GFAP, ChAT, GOGAT, and BBB scores were significantly higher than that of the control group ( p < 0.05); SEP and MEP latency time were significantly shorter than that of the control group ( p < 0.05), and wave amplitude was significantly greater than that of the control group ( p < 0.05). The cBMMSC transplantation based on nanosilver hydrogel nerve conduit was effective in repairing spinal cord injury, promoting neuronal and axonal regeneration, and restoring neuromotor and electrophysiological functions.