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Abstract: Previous studies have demonstrated that high concentrations of methyl-β-cyclodextrin (MβCD, 10–15 mM) can interfere with the formation of lipid rafts and inhibit activation of lymphocytes. In this report, we determined that lower concentrations of MβCD (1–4 mM) could accelerate the proliferation of lymphocytes in human peripheral blood mononuclear cells (PBMCs). In the expanded cells, CD3-CD56+ natural killer (NK) cells were the dominant subpopulation, and a significant dose–effect relationship existed between the proportion of NK cells and the concentration of MβCD. In the groups treated with 3–4 mM MβCD, the proportions of NK cells reached a level of more than 60%. When PBMCs were treated with MβCD, CD69 was more preferentially expressed on CD3-CD56+ cells than on CD3+ cells at 48 and 72 hours. The expression of CD25 had no distinct difference at 48 hours, but when recombinant human interleukin-2 (IL-2) was added for a further 24 hours, it was also preferentially expressed on NK cells. MβCD and IL-2 synergistically could also induce interferon-γ (IFN-γ) production in CD56+ human PBMCs. Mechanistic studies revealed that IFN-γ production in response to MβCD plus IL-2 was IL-12 independent but depended on endogenous IL-18 and IL-1β, and CD56+CD14+ dendritic cell-like cells and B cells might mediate the ability of MβCD to activate NK cells. The MβCD-activated NK cells also had high cytotoxicity against the natural killer cell–sensitive K562 cells or lymphokine-activated killer cell–sensitive DAUDI cells in vitro. These studies indicated that lower concentrations of MβCD combined with IL-2 can preferentially induce activation and proliferation of NK cells in PBMCs. [Copyright &y& Elsevier]

Lipid rafts are cholesterol-enriched microdomains which act as a platform for the initiation of T-cell activation. To investigate effect of endogenous cholesterol on lipid rafts formation and activation of γδT cells, human peripheral blood mononuclear cells were stimulated in vitro with Mycobacterium tuberculosis antigens (Mtb-Ag). Lovastatin and fluvastatin, two 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (HMGCR) inhibitors, were used to block endogenous cholesterol biosynthesis. The expression of ganglioside GM1 (GM1), a lipid rafts marker, and CD69, an activation marker, and the level of tyrosine phosphorylation in γδT cells were measured by flow cytometry. The expression and aggregation of GM1 were also detected with laser confocal microscopy. We found that lovastatin and fluvastatin could obviously inhibit tyrosine phosphorylation and expression of GM1 and CD69 in γδT cells induced by Mtb-Ag. These results collectively indicated that HMGCR inhibitors might interfere with the formation of lipid rafts and inhibit the activation of γδT cells induced by Mtb-Ag. [ABSTRACT FROM AUTHOR]

Abstract: The central nervous system (CNS) is considered to be an immune-privileged site. For a long time, autoimmunity-induced inflammation has been viewed as an important mediator of secondary damage in the CNS following injury. However, other studies also suggest that autoimmunity is protective and beneficial. To investigate whether protective autoimmunity is present following spinal cord injury (SCI), we employed neonatally thymectomized (Tx) rats which contain few T lymphocytes in their peripheral blood, and passively immunized them with T lymphocytes activated by myelin basic protein (MBP) or spinal cord homogenate (SCH). Here we report that, among Tx, sham-Tx (sTx) and normal rats that received a contusive SCI, no significant histological and behavioral differences were found, suggesting that the endogenous T lymphocytes had no significant influence on the pathogenesis of secondary SCI. In rats passively immunized with MBP- or SCH-activated T cells (MBP-T or SCH-T, respectively), similar numbers of CD4+ T cells were found to infiltrate into the injured spinal cords. However, only the MBP-T immunization showed neuroprotection, evidenced by the reduction of post-traumatic neuronal losses and improvement of functional recovery. These results collectively suggest that not all T lymphocytes against CNS antigens are neuroprotective and that a subpopulation of them, such as those of MBP-T cells, could be beneficial for SCI repair. [Copyright &y& Elsevier]

Background: Inflammatory reactions induced by spinal cord injury (SCI) are essential for recovery after SCI. Atractylenolide III (ATL‐III) is a natural monomeric herbal bioactive compound that is mainly derived in Atractylodes macrocephala Koidz and has anti‐inflammatory and neuroprotective effects. Objective: Here, we speculated that ATL‐III may ameliorate SCI by modulating microglial/macrophage polarization. In the present research, we focused on investigating the role of ATL‐III on SCI in rats and explored the potential mechanism. Methods: The protective and anti‐inflammatory effects of ATL‐III on neuronal cells were examined in a rat SCI model and lipopolysaccharide (LPS)‐stimulated BV2 microglial line. The spinal cord lesion area, myelin integrity, and surviving neurons were assessed by specific staining. Locomotor function was evaluated by the Basso, Beattie, and Bresnahan (BBB) scale, grid walk test, and footprint test. The activation and polarization of microglia/macrophages were assessed by immunohistofluorescence and flow cytometry. The expression of corresponding inflammatory factors from M1/M2 and the activation of relevant signaling pathways were assessed by Western blotting. Results: ATL‐III effectively improved histological and functional recovery in SCI rats. Furthermore, ATL‐III promoted the transformation of M1 into M2 and attenuated the activation of microglia/macrophages, further suppressing the expression of corresponding inflammatory mediators. This effect may be partly mediated by inhibition of neuroinflammation through the NF‐κB, JNK MAPK, p38 MAPK, and Akt pathways. Conclusion: This study reveals a novel effect of ATL‐III in the regulation of microglial/macrophage polarization and provides initial evidence that ATL‐III has potential therapeutic benefits in SCI rats. [ABSTRACT FROM AUTHOR]

Apoptosis associated speck like protein containing a card (ASC), the key adaptor protein of the assembly and activation of canonical inflammasomes, has been found to play a significant role in neuroinflammation after spinal cord injury (SCI). The previous studies indicated that widely block or knockout ASC can ameliorate SCI. However, ASC is ubiquitously expressed in infiltrated macrophages and local microglia, so further exploration is needed on which type of cell playing the key role. In this study, using the LysMcre;Ascflox/flox mice with macrophage-specifc ASC conditional knockout (CKO) and contusive SCI model, we focus on evaluating the specific role of ASC in lysozyme 2 (LysM)+ myeloid cells (mainly infiltrated macrophages) in this pathology. The results revealed that macrophage-specifc Asc CKO exhibited the follow effects: (1) A significant reduction in the numbers of infiltrated macrophages in the all phases of SCI, and activated microglia in the acute and subacute phases. (2) A significant reduction in ASC, caspase-1, interleukin (IL)-1β, and IL-18 compared to control mice. (3) In the acute and subacute phases of SCI, M1 subset differentiation was inhibited, and M2 differentiation was increased. (4) Histology and hindlimb motor recoveries were improved. In conclusion, this study elucidates that macrophage-specific ASC CKO can improve nerve function recovery after SCI by regulating M1/M2 polarization through inhibiting ASC-dependent inflammasome signaling axis. This indicates that ASC in peripheral infiltrated macrophages may play an important role in SCI pathology, at least in mice, could be a potential target for treatment. [Display omitted] • Asc CKO can reduce the infiltration of macrophages after SCI in mice. • Asc CKO can reduce the activated microglia in the acute and subacute phases of SCI. • Asc CKO can inhibit ASC-dependent inflammasome signaling axis. • Asc CKO can inhibit M1 polarization, and increase M2 polarization. • Asc CKO can improve histology and hindlimb motor recoveries after SCI. [ABSTRACT FROM AUTHOR]

Inflammation is one of the key injury factors for spinal cord injury (SCI). Exosomes (Exos) derived from M2 macrophages have been shown to inhibit inflammation and be beneficial in SCI animal models. However, lacking targetability restricts their application prospects. Considering that chemokine receptors increase dramatically after SCI, viral macrophage inflammatory protein II (vMIP-II) is a broad-spectrum chemokine receptor binding peptide, and lysosomal associated membrane protein 2b (Lamp2b) is the key membrane component of Exos, we speculated that vMIP-II-Lamp2b gene-modified M2 macrophage-derived Exos (vMIP-II-Lamp2b-M2-Exo) not only have anti-inflammatory properties, but also can target the injured area by vMIP-II. In this study, using a murine contusive SCI model, we revealed that vMIP-II-Lamp2b-M2-Exo could target the chemokine receptors which highly expressed in the injured spinal cords, inhibit some key chemokine receptor signaling pathways (such as MAPK and Akt), further inhibit proinflammatory factors (such as IL-1β, IL-6, IL-17, IL-18, TNF-α, and iNOS), and promote anti-inflammatory factors (such as IL-4 and Arg1) productions, and the transformation of microglia/macrophages from M1 into M2. Moreover, the improved histological and functional recoveries were also found. Collectively, our results suggest that vMIP-II-Lamp2b-M2-Exo may provide neuroprotection by targeting the injured spinal cord, inhibiting some chemokine signals, reducing proinflammatory factor production and modulating microglia/macrophage polarization. [Display omitted] • vMIP-II-Lamp2b-M2-Exo can target the injured spinal cord by vMIP-II. • vMIP-II-Lamp2b-M2-Exo can inhibit MAPK and AKT signaling pathways. • vMIP-II-Lamp2b-M2-Exo can reduce proinflammatory factor production. • vMIP-II-Lamp2b-M2-Exo can inhibit M1 microglia/macrophage polarization. • The early administration of vMIP-II-Lamp2b-M2-Exo is a promising strategy for SCI. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI. • Serum exosomes of sham and subactue SCI rats were isolated and identified. • Serum exosomal microRNA transcriptome profiling in subacute spinal cord injured rats is investigated. • The changed miRNAs and their associated signaling pathways have been systematically determined. • Our results will provide a basis for the pathological mechanism, diagnosis and prognosis of SCI. [ABSTRACT FROM AUTHOR]

Previous studies have shown that caspase-1 plays an important role in the acute inflammatory response of spinal cord injury (SCI). VX-765, a novel and irreversible caspase-1 inhibitor, has been reported to effectively intervene in inflammation. However, the effect of VX-765 on genome-wide transcription in acutely injured spinal cords remains unknown. Therefore, in the present study, RNA-sequencing (RNA-Seq) was used to analyze the effect of VX-765 on the local expression of gene transcription 8 h following injury. The differentially expressed genes (DEGs) underwent enrichment analysis of functions and pathways by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, respectively. Parallel analysis of western blot confirmed that VX-765 can effectively inhibit the expression and activation of caspase-1. RNA-Seq showed that VX-765 treatment resulted in 1,137 upregulated and 1,762 downregulated DEGs. These downregulated DEGs and their associated signaling pathways, such as focal adhesion, cytokine-cytokine receptor interaction, leukocyte transendothelial migration, extracellular matrix-receptor interaction, phosphatidylinositol 3-kinase-protein kinase B, Rap1 and hypoxia inducible factor-1 signaling pathway, are mainly associated with inflammatory response, local hypoxia, macrophage differentiation, adhesion migration and apoptosis of local cells. This suggests that the application of VX-765 in the acute phase can improve the local microenvironment of SCI by inhibiting caspase-1. However, whether VX-765 can be used as a therapeutic drug for SCI requires further exploration. The sequence data have been deposited into the Sequence Read Archive (https://www.ncbi.nlm.nih.gov/sra/PRJNA548970). [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI. [ABSTRACT FROM AUTHOR]

The underlying mechanisms of macrophage polarization have been detected by genome-wide transcriptome analysis in a variety of mammals. However, the transcriptome profile of rat genes in bone marrow-derived macrophages (BMM) at different activation statuses has not been reported. Therefore, we performed RNA-Sequencing to identify gene expression signatures of rat BMM polarized in vitro with different stimuli. The differentially expressed genes (DEGs) among unactivated (M0), classically activated pro-inflammatory (M1), and alternatively activated anti-inflammatory macrophages (M2) were analyzed by using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. In this study, not only we have identified the changes of global gene expression in rat M0, M1 and M2, but we have also made clear systematically the key genes and signaling pathways in the differentiation process of M0 to M1 and M2. These will provide a foundation for future researches of macrophage polarization. • The transcriptome profile of rat genes in bone marrow-derived macrophages at different activation statuses is investigated. • The global gene expression in rat M0, M1 and M2 has been described. • The key genes and signaling pathways in the differentiation process of M0 to M1 and M2 have been systematically determined. • Our results will provide a basis for future researches of macrophage polarization. [ABSTRACT FROM AUTHOR]

Hexokinase-3 (HK3) is a member of hexokinase family, which can catalyze the first step of glucose metabolism. It can increase ATP levels, reduce the production of reactive oxygen species, increase mitochondrial biogenesis, protect mitochondrial membrane potential and play an antioxidant role. However, the change of its expression in spinal cord after injury is still unknown. In this study, we investigated the spatio-temporal expression of HK3 in the spinal cords by using a spinal cord injury (SCI) model in adult female Sprague-Dawley rats. Quantitative reverse transcription-PCR and western blot analysis revealed that HK3 could be detected in sham-opened spinal cords. After SCI, it gradually increased, reached a peak at 7 days post-injury (dpi), and then gradually decreased with the prolonging of injury time, but still maintained at a higher level for up to 28 dpi (the longest time evaluated in this study). Immunofluorescence staining showed that HK3 was found in GFAP + , β-tubulin III + and IBA-1 + cells in sham-opened spinal cords. After SCI, in addition to the above-mentioned cells, it could also be found in CD45 + and CD68 + cells. These results demonstrate that HK3 is mainly expressed in astrocytes, neurons and microglia in normal spinal cords, and could rapidly increase in infiltrated leukocytes, activated microglia/macrophages and astrocytes after SCI. These data suggest that HK3 may be involved in the pathologic process of SCI by promoting glucose metabolism. [ABSTRACT FROM AUTHOR]

Oligodendrocyte (OL) replacement is a promising treatment strategy for spinal cord injury (SCI). However, the poor survival of transplanted OLs or their precursors and inhibition of axonal regeneration are two major challenges with this approach. Our previous study showed that Schwann cells (SCs) promoted survival, proliferation, and migration of transplanted OL progenitor cells (OPCs) and neurological recovery. Remyelination is an important basis for functional recovery following spinal cord injury. It has been reported that myelin gene regulatory factor (MRF), a transcriptional regulator which specifically is expressed in postmitotic OLs within the CNS, is essential for OL maturation and CNS myelination. In the present study, we investigated whether co-transplantation of MRF-overexpressing OPCs (MRF-OPCs) and SCs could improve functional recovery in a rat model of contusional SCI. MRF overexpression had no effect on OPC survival or migration, but stimulated the differentiation of OPCs both in vitro and in vivo. Co-transplantation of MRF-OPCs and SCs increased myelination and tissue repair after SCI, leading to the recovery of neurological function. These results indicate that co-transplantation of MRF-OPCs and SCs may be an effective treatment strategy for SCI. [ABSTRACT FROM AUTHOR]

Myelin basic protein (MBP) activated T cells (MBP-T) play an important role in the damage and repair process of the central nervous system (CNS). However, whether these cells play a beneficial or detrimental role is still a matter of debate. Although some studies showed that MBP-T cells are mainly helper T (Th) cells, their subtypes are still not very clear. One possible explanation for MBP-T immunization leading to conflicting results may be the different subtypes of T cells are responsible for distinct effects. In this study, the Th1 and Th2 type MBP-T cells (MBP-Th1 and -Th2) were polarized in vitro, and their effects on the local immune microenvironment and tissue repair of spinal cord injury (SCI) after adoptive immunization were investigated. In MBP-Th1 cell transferred rats, the high levels of pro-inflammatory cells (Th1 cells and M1 macrophages) and cytokines (IFN-γ, TNF-α, -β, IL-1β) were detected in the injured spinal cord; however, the anti-inflammatory cells (Th2 cells, regulatory T cells, and M2 macrophages) and cytokines (IL-4, -10, and -13) were found in MBP-Th2 cell transferred animals. MBP-Th2 cell transfer resulted in decreased lesion volume, increased myelination of axons, and preservation of neurons. This was accompanied by significant locomotor improvement. These results indicate that MBP-Th2 adoptive transfer has beneficial effects on the injured spinal cord, in which the increased number of Th2 cells may alter the local microenvironment from one primarily populated by Th1 and M1 cells to another dominated by Th2, Treg, and M2 cells and is conducive for SCI repair. [ABSTRACT FROM AUTHOR]

Classically activated pro-inflammatory (M1) and alternatively activated anti-inflammatory (M2) macrophages populate the local microenvironment after spinal cord injury (SCI). The former type is neurotoxic while the latter has positive effects on neuroregeneration and is less toxic. In addition, while the M1 macrophage response is rapidly induced and sustained, M2 induction is transient. A promising strategy for the repair of SCI is to increase the fraction of M2 cells and prolong their residence time. This study investigated the effect of M2 macrophages induced from bone marrow-derived macrophages on the local microenvironment and their possible role in neuroprotection after SCI. M2 macrophages produced anti-inflammatory cytokines such as interleukin (IL)-10 and transforming growth factor β and infiltrated into the injured spinal cord, stimulated M2 and helper T (Th)2 cells, and produced high levels of IL-10 and -13 at the site of injury. M2 cell transfer decreased spinal cord lesion volume and resulted in increased myelination of axons and preservation of neurons. This was accompanied by significant locomotor improvement as revealed by Basso, Beattie and Bresnahan locomotor rating scale, grid walk and footprint analyses. These results indicate that M2 adoptive transfer has beneficial effects for the injured spinal cord, in which the increased number of M2 macrophages causes a shift in the immunological response from Th1- to Th2-dominated through the production of anti-inflammatory cytokines, which in turn induces the polarization of local microglia and/or macrophages to the M2 subtype, and creates a local microenvironment that is conducive to the rescue of residual myelin and neurons and preservation of neuronal function. [ABSTRACT FROM AUTHOR]

• The results of RNA-seq confirmed the anti-inflammatory and anti-apoptotic effects of morroniside on injured SC tissues. • Some key signal pathways and molecules may be involved in the SC protection of morroniside. • The data provided the basis for further studying the mechanism of the protective effects of morroniside on SCI. We have previously reported that morroniside promoted motor activity after spinal cord injury (SCI) in rats. However, the mechanism by which morroniside induces recovery of injured spinal cord (SC) remains unknown. In the current study, RNA sequencing (RNA-seq) was employed to evaluate changes of gene expressions at the transcriptional level of the injured spinal cords in morroniside-administrated rats. Principal component analysis, analysis of enriched Gene Ontology (GO), enrichment analyses Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and other bioinformatics analyses were executed to distinguish differentially expressed genes (DEGs). The results of RNA-seq confirmed the anti-inflammatory and anti-apoptotic effects of morroniside on injured SC tissues, and provided the basis for additional research of the mechanisms involving the protective effects of morroniside on SCI. [ABSTRACT FROM AUTHOR]

The conditioned medium from B104 neuroblastoma cells (B104CM) induces proliferation of oligodendrocyte progenitor cells (OPCs) in vitro. However, the molecular events that occur during B104CM-induced proliferation of OPCs has not been well clarified. In the present study, using OPCs immunopanned from embryonic day 14 Sprague-Dawley rat spinal cords, we explored the activation of several signaling pathways and the expression of several important immediate early genes (IEGs) and cyclins in OPCs in response to B104CM. We found that B104CM can induce OPC proliferation through the activation of the extracellular signal-regulated kinases 1 and 2 (Erk1/2), but not PI3K or p38 MAPK signaling pathways in vitro. The IEGs involved in B104CM-induced OPC proliferation include c-fos, c-jun and Id2, but not c-myc, fyn, or p21. The cyclins D1, D2 and E are also involved in B104CM-stimulated proliferation of OPCs. The activation of Erk results in subsequent expression of IEGs (such as c-fos, c-jun and Id-2) and cyclins (including cyclin D1, D2 and E), which play key roles in cell cycle initiation and OPC proliferation. Collectively, these results suggest that the phosphorylation of Erk1/2 is an important molecular event during OPC proliferation induced by B104CM. [ABSTRACT FROM AUTHOR]

The previous studies suggested that some subpopulations of T lymphocytes against central nervous system (CNS) antigens, such as myelin basic protein (MBP), are neuroprotective. But there were few reports about the effect of these T cells on axon regeneration. In this study, the neonatally thymectomied (Tx) adult rats which contain few T lymphocytes were subjected to spinal cord hemisection and then passively immunized with MBP-activated T cells (MBP-T). The regeneration and dieback of transected axons of cortico-spinal tract (CST) were detected by biotin dextran amine (BDA) tracing. The behavioral assessments were performed using the Basso, Beattie, and Bresnahan locomotor rating scale. We found that passive transferring of MBP-T could attenuate axonal dieback. However, no significant axon regeneration and behavioral differences were observed among the normal, Tx and sham-Tx (sTx) rats with or without MBP-T passive immunization. These results indicate that passive transferring of MBP-T cells can attenuate axonal dieback and promote neuroprotection following spinal cord injury (SCI), but may not promote axon regeneration. [ABSTRACT FROM AUTHOR]

Abstract: Although the role of astrocyte glutamate transporters in glutamate clearance is well illustrated, the role of glutamine synthetase (GS) that influences this process remains to be elucidated. We examined whether GS affected the uptake of glutamate in astrocytes in vitro. The glutamate uptake was assessed by measuring the concentration of glutamate and glutamine in culture medium in the presence or absence of glutamate. We demonstrated that inhibition of GS in astrocytes by MSO significantly impaired glutamate uptake and glutamine release. Conversely, induction of GS expression in astrocytes by gene transfer significantly enhanced the glutamate uptake and glutamine release. When an inflammatory cytokine tumor necrosis factor-α (TNF-α) was applied to the cultures, it significantly reduced GS expression and inhibited glutamate-induced GS activation resulting in increased excitotoxicity to neurons. These results suggest that GS in astrocytes may represent a novel target for neuroprotection against neuronal dysfunction and death that occur in many neurological disorders. [Copyright &y& Elsevier]

Spinal cord injury (SCI) is a disabling condition that often leads to permanent neurological deficits without an effective treatment. Reactive oxygen species (ROS) produced during oxidative stress play a vital role in the pathogenesis following SCI. The antioxidant morroniside is the main active component of the Chinese medicine Cornus officinalis. In recent years, it has been reported that morroniside has therapeutic effects on damage to multiple organs mediated by oxidative damage, but the effect of morroniside on SCI has not been reported. The purpose of this study was therefore to assess the therapeutic effect of morroniside on SCI, and to identify its underlying mechanism by direct intragastric administration immediately after SCI. Our study showed that morroniside treatment improved the functional recovery of rats following SCI. This behavioral improvement was associated with the higher survival in neurons and oligodendrocytes following SCI, which increased the capacity of injured spinal cord (SC) to form myelin and repair tissue, eventually contributing to improved neurological outcome. Furthermore, our study found that oxygen free radicals increased and antioxidant enzyme activity decreased in the injured SC. Interestingly, morroniside treatment decreased oxygen free radical levels and increased antioxidant enzyme activities. Together, our results suggested that morroniside may be an effective treatment for improving outcomes following SCI, and that its antioxidant activity may be one of the mechanisms by which morroniside exerts neuroprotective effects on SCI. • Morroniside significantly promoted the histological recoveries of injured SC tissue and locomotor function in rats after SCI. • Morroniside inhibited oxidative stress and promoted the survival of neurons and OLs in injured SC. • Morroniside may be an effective treatment for improving outcomes following SCI. [ABSTRACT FROM AUTHOR]

Background: After spinal cord injury (SCI), destructive immune cell subsets are dominant in the local microenvironment, which are the important mechanism of injury. Studies have shown that inflammasomes play an important role in the inflammation following SCI, and apoptosis-associated speck-like protein containing a card (ASC) is the adaptor protein shared by inflammasomes. Therefore, we speculated that inhibiting ASC may improve the local microenvironment of injured spinal cord. Here, CRID3, a blocker of ASC oligomerization, was used to study its effect on the local microenvironment and the possible role in neuroprotection following SCI.Methods: Murine SCI model was created using an Infinite Horizon impactor at T9 vertebral level with a force of 50 kdynes and CRID3 (50 mg/kg) was intraperitoneally injected following injury. ASC and its downstream molecules in inflammasome signaling pathway were measured by western blot. The immune cell subsets were detected by immunohistofluorescence (IHF) and flow cytometry (FCM). The spinal cord fibrosis area, neuron survival, myelin preservation, and functional recovery were assessed.Results: Following SCI, CRID3 administration inhibited inflammasome-related ASC and caspase-1, IL-1β, and IL-18 activation, which consequently suppressed M1 microglia, Th1 and Th1Th17 differentiation, and increased M2 microglia and Th2 differentiation. Accordingly, the improved histology and behavior have also been found.Conclusions: CRID3 may ameliorate murine SCI by inhibiting inflammasome activation, reducing proinflammatory factor production, restoring immune cell subset balance, and improving local immune microenvironment, and early administration may be a promising therapeutic strategy for SCI. [ABSTRACT FROM AUTHOR]