The Role of Microglia/Macrophages Activation and TLR4/NF-κB/MAPK Pathway in Distraction Spinal Cord Injury-Induced Inflammation

Rutin Attenuates Distraction Spinal Cord Injury by Inhibiting Microglial Inflammation Through Downregulation of P38 MAPK/NF-κB/STAT3 Pathway

Distraction spinal cord injury (DSCI) is a severe complication following scoliosis correction surgery, for which there are currently no effective clinical treatments. This study aims to evaluate the inhibitory effects of rutin, a natural product, on inflammation in DSCI and to investigate the underlying mechanisms. In vitro, microglial cells were exposed directly to rutin to assess its ability to inhibit lipopolysaccharide (LPS)-induced inflammation. In rats with DSCI, the inhibitory effect of rutin on DSCI was evaluated using behavioral tests. mRNA sequencing was performed on spinal cord tissues to elucidate the mechanism of rutin's action. Rutin significantly suppressed the LPS-induced increase in inflammatory factors in microglial cells. In DSCI rats treated with rutin, scores in the Basso-Beattie-Bresnahan (BBB) were significantly improved. The mechanism of rutin's action was found to be related to its ability to reduce inflammatory infiltration in spinal cord tissue, protecting neurons from apoptosis and microstructural demyelination. Through assays of transcriptomic differentially expressed genes (DEGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and RT-qPCR validation of the top DEGs, MAPK13 (also known as P38 MAPK) was finally identified as the key target gene in promoting DSCI development. Further molecular docking analysis indicated an interaction between rutin and P38 MAPK, supporting the rutin's action and the underlying mechanism in anti-inflammation. In conclusion, rutin effectively inhibited the development of DSCI in rats. The mechanism of rutin's action was associated with its activity in blocking the P38 MAPK/NF-κB/STAT3 pathway in the microglial cells of spinal cord. Rutin could be developed as a potential anti-DSCI drug for clinical applications.

Deciphering the Neuroprotective Action of Bee Venom Peptide Melittin: Insights into Mechanistic Interplay

Neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis, are characterized by progressive loss of neuronal structure and function. These conditions often lead to cognitive decline, motor dysfunction, and ultimately severe impairment of daily activities. A key feature of neurodegenerative diseases is chronic inflammation, which contributes to neuronal damage and exacerbates disease progression. Traditional treatments mainly focus on symptomatic relief rather than addressing the underlying causes, highlighting the need for novel therapeutic approaches. Melittin, a bioactive peptide derived from bee venom, has garnered attention for its multifaceted neuroprotective properties, particularly in the context of neuroinflammatory and neurodegenerative disorders. This review delves into the molecular mechanisms through which melittin exerts neuroprotective effects, with a focus on its ability to modulate neuroinflammation, apoptosis, and neurogenesis. Research indicates that melittin can downregulate pro-apoptotic pathways by inhibiting calpain-mediated activation of apoptosis-inducing factor and Bax, thereby reducing neuronal cell death. Additionally, melittin exerts its neuroprotective effects through the inhibition of neuroinflammatory processes, specifically by downregulating key inflammatory pathways such as NF-κB and MAPK. This modulation leads to decreased production of proinflammatory cytokines and prostaglandins, which are implicated in the pathogenesis of neurodegenerative disorders. Beyond its anti-inflammatory actions, melittin promotes neurogenesis, potentially through the modulation of the BDNF/Trk-B/CREB signaling pathway, which plays a crucial role in neuronal survival and plasticity. These properties suggest that melittin not only provides symptomatic relief but could also address the root causes of neuronal degeneration, presenting a promising avenue for the development of new treatments for neurodegenerative diseases. Further research is required to validate its efficacy and safety in clinical settings.

Fructose induces inflammatory activation in macrophages and microglia through the nutrient-sensing ghrelin receptor

High fructose corn syrup (HFCS) is a commonly used sweetener in soft drinks and processed foods, and HFCS exacerbates inflammation when consumed in excess. Fructose, a primary component of HFCS; however, it is unclear whether fructose directly activates inflammatory signaling. Growth hormone secretagogue receptor (GHSR) is a receptor of the nutrient-sensing hormone ghrelin. We previously reported that GHSR ablation mitigates HFCS-induced inflammation in adipose tissue and liver, shifting macrophages toward an anti-inflammatory spectrum. Since inflammation is primarily governed by innate immune cells, such as macrophages in the peripheral tissues and microglia in the brain, this study aims to investigate whether GHSR autonomously regulates pro-inflammatory activation in macrophages and microglia upon fructose exposure. GHSR deletion mutants of RAW 264.7 macrophages and the immortalized microglial cell line (IMG) were generated using CRISPR-Cas9 gene editing. After treating the cells with equimolar concentrations of fructose or glucose for 24 h, fructose increased mRNA and protein expression of GHSR and pro-inflammatory cytokines (Il1β, Il6, and Tnfα) in both macrophages and microglia, suggesting that fructose activates Ghsr and induces inflammation directly in macrophages and microglia. Remarkably, GHSR deletion mutants (Ghsrmutant) of macrophages and microglia exhibited reduced inflammatory responses to fructose, indicating that GHSR mediates fructose-induced inflammation. Furthermore, we found that GHSR regulates fructose transport and fructose metabolism and mediates fructose-induced inflammatory activation through CREB-AKT-NF-κB and p38 MAPK signaling pathways. Our results underscore that fructose triggers inflammation, and reducing HFCS consumption would reduce disease risk. Moreover, these findings reveal for the first time that the nutrient-sensing receptor GHSR plays a crucial role in fructose-mediated inflammatory activation, suggesting that targeting GHSR may be a promising therapeutic approach to combat the immunotoxicity of foods that contain fructose.

The Impact of Nuclear Factor Kappa B on the Response of Microglia in Spinal Cord Injuries

Spinal cord injury (SCI) results in both primary and secondary damage, each contributing to the overall injury and its consequences. Following SCI, microglia, the resident immune cells of the central nervous system (CNS), undergo a series of complex responses that contribute to the pathophysiology of the injury. In the context of SCI, nuclear factor kappa B (NF-kB) emerged as a critical mediator in the regulation of inflammatory responses following SCI. The aim of this review is to provide a comprehensive understanding of the involvement of NF-kB in the response of microglia following SCI. The PUBMED database was searched using the following keywords: NF-kB AND microglia AND spinal cord injury. Clinical and experimental studies evaluating the role of NF-kB in the response of microglia following SCI were included. Systematic reviews, case reports, research protocols, conference articles, and studies in languages other than English were excluded. The final analysis included 52 studies. NF-kB signaling exerts profound effects on the microglial response following SCI, influencing the inflammatory milieu, tissue damage, and potential for repair and recovery. Deactivation of the NF-kB signaling pathway suppresses the production of proinflammatory mediators in microglia, after SCI. Moreover, NF-kB suppression has neuroprotective effects, as it mitigates neuronal apoptosis and facilitates the M2 microglial phenotype, alleviating tissue damage after SCI. Moreover, several microRNAs play a crucial role in regulating gene expression post-transcriptionally and have emerged as key regulators in microglia activation after SCI. Overall, the role of NF-kB in the response of microglia to SCI is complex and context-dependent. While NF-kB activation is involved in initiating and propagating the inflammatory response following SCI, it also plays a role in tissue repair and regeneration. Thus, modulating NF-kB signaling in microglia represents a potential therapeutic target for attenuating inflammation and promoting neuroprotection and tissue repair in SCI.

MAPK signaling pathway in spinal cord injury: Mechanisms and therapeutic potential

Spinal cord injury (SCI) is a severe disabling injury of the central nervous system that can lead to motor, sensory, and autonomic dysfunction below the level of the injury. According to its pathophysiological process, SCI can be divided into primary injury and secondary injury. Currently, multiple therapeutic strategies have been proposed to alleviate secondary injury and overcome the occurrence of neurodegenerative events. Although current treatment modalities have achieved varying degrees of success, they cannot effectively intervene or treat its pathological processes, which may be due to the complex treatment and protection mechanisms involved. Research has confirmed that signaling pathways play a crucial role in the pathological processes of SCI and the mechanisms of neuronal recovery. Mitogen-activated protein kinase (MAPK) signaling pathway plays a crucial role in neuronal differentiation, growth, survival and axon regeneration after central nervous system injury. Meanwhile, the MAPK signaling pathway is an important pathway closely related to the pathological processes of SCI. The MAPK signaling pathway is abnormally activated after SCI, and inhibiting the activity of MAPK pathway can effectively inhibit inflammation, oxidative stress, pain and apoptosis to promote the recovery of nerve function after SCI. Based on the role of the MAPK pathway in SCI, it may be a potential therapeutic target. This article summarizes the role and mechanism of MAPK pathway in SCI, and discusses the shortcomings and shortcomings of MAPK pathway in SCI field, as well as the potential challenges of targeting MAPK pathway in SCI treatment strategies. This article aims to elucidate the mechanism of the MAPK pathway in SCI to emphasize the role of targeting the MAPK pathway in the treatment of SCI, providing a theoretical basis for the MAPK pathway as a potential therapeutic target for SCI treatment.

Inhibition of lncEPS by TLR4/NF-κB pathway induces ventilator-induced lung injury by decreasing its binding to and upregulating Hspa5

Whether LincRNA erythroid prosurvival (LncEPS) reduces VILI remains unclear. A GSE200932 microarray was used to screen differentially expressed genes (DEGs). A VILI mouse model was constructed by mechanical ventilation (MV), with or without TAK242 or SN50 pretreatment. Airway transfection with adeno-associated virus (AAV) was used to overexpress lncEPS in alveolar macrophages (AMs). Lung tissues were collected to assess pathological injury and macrophage polarization. NLRP3 inflammasome, TLR4/NF-κB pathway activation and heat shock protein family A member 5 (Hspa5) in lung tissue and AMs wre evaluated. LncEPS localization and regulatory changes were assessed using in situ hybridization and RT-PCR. Lung tissues after lncEPS overexpression were subjected to transcriptomics. Chromatin isolation and mass spectrometry (MS) were performed to identify proteins interacting with lncEPS. GSE200932 microarray showed that the DEGs were related to NF-κB pathway, Toll-like receptor pathway and NOD-like receptor pathway. TAK242 or SN50 treatment increased polarization of M2 macrophages and decreased NLRP3 inflammasome activation by inhibiting TLR4/NF-κB pathway in VILI. Inhibition of TLR4/NF-κB pathway upregulated lncEPS expression in AMs. Overexpression of lncEPS increased polarization of M2 macrophages and decreased NLRP3 inflammasome activation, eventually alleviating VILI in mice. Mechanistically, lncEPS bound to Hspa5 and downregulated its expression to inhibit inflammatory response.

Neuroplasticity in the transition from acute to chronic pain

Acute pain is a transient sensation that typically serves as part of the body's defense mechanism. However, in certain patients, acute pain can evolve into chronic pain, which persists for months or even longer. Neuroplasticity refers to the capacity for variation and adaptive alterations in the morphology and functionality of neurons and synapses, and it plays a significant role in the transmission and modulation of pain. In this paper, we explore the molecular mechanisms and signaling pathways underlying neuroplasticity during the transition of pain. We also examine the effects of neurotransmitters, inflammatory mediators, and central sensitization on neuroplasticity, as well as the potential of neuroplasticity as a therapeutic strategy for preventing chronic pain. The aims of this article is to clarify the role of neuroplasticity in the transformation from acute pain to chronic pain, with the hope of providing a novel theoretical basis for unraveling the pathogenesis of chronic pain and offering more effective strategies and approaches for its diagnosis and treatment.

Aucubin suppresses TLR4/NF-κB signalling to shift macrophages toward M2 phenotype in glucocorticoid-associated osteonecrosis of the femoral head

In this study, we investigated whether the ability of aucubin to mitigate the pathology of GONFH involves suppression of TLR4/NF-κB signalling and promotion of macrophage polarization to an M2 phenotype. In necrotic bone tissues from GONFH patients, we compared levels of pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages as well as levels of TLR4/NF-κB signalling. In a rat model of GONFH, we examined the effects of aucubin on these parameters. We further explored its mechanism of action in a cell culture model of M1 macrophages. Necrotic bone tissues from GONFH patients contained a significantly increased macrophage M1/M2 ratio, and higher levels of TLR4, MYD88 and NF-κB p65 than bone tissues from patients with hip osteoarthritis. Treating GONFH rats with aucubin mitigated bone necrosis and demineralization as well as destruction of trabecular bone and marrow in a dose-dependent manner, based on micro-computed tomography. These therapeutic effects were associated with a decrease in the overall number of macrophages, decrease in the proportion of M1 macrophages, increase in the proportion of M2 macrophages, and downregulation of TLR4, MYD88 and NF-κB p65. These effects in vivo were confirmed by treating cultures of M1 macrophage-like cells with aucubin. Aucubin mitigates bone pathology in GONFH by suppressing TLR4/NF-κB signalling to shift macrophages from a pro- to anti-inflammatory phenotype.

Effect of captopril on paraplegia caused by spinal cord ischemia-reperfusion injury in rats

This study investigated the effect of captopril (Cap) on spinal cord ischemia-reperfusion injury (SCII) in rats. Twenty-four adults male Wistar rats were randomly divided into four groups of six animals each: spinal cord ischemia-reperfusion (SCI-R) with Cap (SCI-R + Cap), SCI-R, sham-operated with Cap (SHAM + Cap), and SHAM. The 24 hr and 90 min before ischemia induction, Cap was administered intragastrically (100 mg kg-1) to the SHAM + Cap and SCI-R + Cap groups. Abdominal aortic clamping was performed in the SCI-R and SCI-R + Cap groups for 40 min. Hindlimb motor function was evaluated using the Tarlov Scale at 4, 6, 12, 24, 48, and 60 hr after SCII. The malondialdehyde (MDA), the ferric-reducing ability of plasma (FRAP) and prooxidant-antioxidant balance (PAB) values were also measured. Throughout the study period, the SCI-R group had significantly lower motor function scores compared to the other groups. The MDA and PAB levels were higher and the FRAP value was lower in the SCI-R group compared to in the SHAM group. The SCI-R + Cap had higher motor function scores compared to the SCI-R group at all time points. There were no significant differences in MDA concentration, FRAP and PAB values between the SCI-R + Cap and SCI-R groups. Captopril may act as a protective agent against SCII in rats based on hind limb motor function assessment.

A Synthetic Derivative SH 66 of Homoisoflavonoid from Liliaceae Exhibits Anti-Neuroinflammatory Activity against LPS-Induced Microglial Cells

Naturally occurring homoisoflavonoids isolated from some Liliaceae plants have been reported to have diverse biological activities (e.g., antioxidant, anti-inflammatory, and anti-angiogenic effects). The exact mechanism by which homoisoflavonones exert anti-neuroinflammatory effects against activated microglia-induced inflammatory cascades has not been well studied. Here, we aimed to explore the mechanism of homoisoflavonoid SH66 having a potential anti-inflammatory effect in lipopolysaccharide (LPS)-primed BV2 murine microglial cells. Microglia cells were pre-treated with SH66 followed by LPS (100 ng/mL) activation. SH66 treatment attenuated the production of inflammatory mediators, including nitric oxide and proinflammatory cytokines, by down-regulating mitogen-activated protein kinase signaling in LPS-activated microglia. The SH66-mediated inhibition of the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome complex and the respective inflammatory biomarker-like active interleukin (IL)-1β were noted to be one of the key pathways of the anti-inflammatory effect. In addition, SH66 increased the neurite length in the N2a neuronal cell and the level of nerve growth factor in the C6 astrocyte cell. Our results demonstrated the anti-neuroinflammatory effect of SH66 against LPS-activated microglia-mediated inflammatory events by down-regulating the NLRP3 inflammasome complex, with respect to its neuroprotective effect. SH66 could be an interesting candidate for further research and development regarding prophylactics and therapeutics for inflammation-mediated neurological complications.

Sp1 Regulates the M1 Polarization of Microglia Through the HuR/NF-κB Axis after Spinal Cord Injury

The M1 polarization of microglia, followed by the production of pro-inflammatory mediators, hinders functional recovery after spinal cord injury (SCI). Our previous study has illuminated that specificity protein 1 (Sp1) expression is increased following SCI, whereas the function and regulatory mechanism of Sp1 during M1 polarization of microglia following SCI remain unknown. RNA binding protein, HuR, has been shown to be up-regulated in the injured spinal cord through analysis of the GEO database. Further investigation using Chip-Atlas data suggests a binding between Sp1 and HuR. Emerging evidence indicates that HuR plays a pivotal role in neuroinflammation after SCI. In this research, Sp1 and HuR levels in mice with SCI and BV2 cells treated with lipopolysaccharide (LPS) was determined by using quantitative real-time polymerase chain reaction and Western blotting techniques. A series of in vitro assays were performed to investigate the function of Sp1 during M1 polarization of microglia. The association between Sp1 and its target gene HuR was confirmed through gene transfection and luciferase reporter assay. Enhanced expression of HuR was observed in both SCI mice and LPS-treated BV2 cells, while Sp1 knockdown restrained M1 polarization of microglia and its associated inflammation by inhibiting the NF-κB signaling pathway. Silencing Sp1 also suppressed microglia activation and its mediated inflammatory response, which could be reversed by overexpression of HuR. In conclusion, silencing Sp1 restrains M1 polarization of microglia through the HuR/NF-κB axis, leading to neuroprotection, and thus promotes functional restoration following SCI.

Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review

Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity. With the increased degree and duration of distraction, spinal cord injuries become more serious in terms of their neurophysiology, histology, and behavior. Very few studies have been published on the specific characteristics of distraction spinal cord injury. In this study, we systematically review 22 related studies involving animal models of distraction spinal cord injury, focusing particularly on the neurophysiological, histological, and behavioral characteristics of this disease. In addition, we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord injury. We provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research, and provide reference guidelines for the clinical diagnosis and treatment of this disease.

CHTOP Promotes Microglia-Mediated Inflammation by Regulating Cell Metabolism and Inflammatory Gene Expression

During the initiation of the inflammatory response of microglia, the expression of many inflammation- and cell metabolism-related genes alters. However, how the transcription of inflammation- and metabolism-related genes are coordinately regulated during inflammation initiation is poorly understood. In this study, we found that LPS stimulation induced the expression of the chromatin target of PRMT1 (protein arginine methyltransferase 1) (CHTOP) in microglia. Knocking down CHTOP in microglia decreased proinflammatory cytokine expression. In addition, CHTOP knockdown altered cell metabolism, as both the upregulated genes were enriched in cell metabolism-related pathways and the metabolites profile was greatly altered based on untargeted metabolomics analysis. Mechanistically, CHTOP could directly bind the regulatory elements of inflammation and cell metabolism-related genes to regulate their transcription. In addition, knocking down CHTOP increased neuronal viability in vitro and alleviated microglia-mediated neuroinflammation in a systemic LPS treatment mouse model. Collectively, these data revealed CHTOP as a novel regulator to promote microglia-mediated neuroinflammation by coordinately regulating the transcription of inflammation and cell metabolism-related genes.

Sarsasapogenin regulates the immune microenvironment through MAPK/NF-kB signaling pathway and promotes functional recovery after spinal cord injury

Spinal cord injury (SCI) occurs as a result of traumatic events that damage the spinal cord, leading to motor, sensory, or autonomic function impairment. Sarsasapogenin (SA), a natural steroidal compound, has been reported to have various pharmacological applications, including the treatment of inflammation, diabetic nephropathy, and neuroprotection. However, the therapeutic efficacy and underlying mechanisms of SA in the context of SCI are still unclear. This research aimed to investigate the therapeutic effects and mechanisms of SA against SCI by integrating network pharmacology analysis and experimental verification. Network pharmacology results suggested that SA may effectively treat SCI by targeting key targets such as TNF, RELA, JUN, MAPK14, and MAPK8. The underlying mechanism of this treatment may involve the MAPK (JNK) signaling pathway and inflammation-related signaling pathways such as TNF and Toll-like receptor signaling pathways. These findings highlight the therapeutic potential of SA in SCI treatment and provide valuable insights into its molecular mechanisms of action. In vivo experiments confirmed the reparative effect of SA on SCI in rats and suggested that SA could repair SCI by modulating the immune microenvironment. In vitro experiments further investigated how SA regulates the immune microenvironment by inhibiting the MAPK/NF-kB pathways. Overall, this study successfully utilized a combination of network pharmacology and experimental verification to establish that SA can regulate the immune microenvironment via the MAPK/NF-kB signaling pathway, ultimately facilitating functional recovery from SCI. Furthermore, these findings emphasize the potential of natural compounds from traditional Chinese medicine as a viable therapy for SCI treatment.

Stigmasterol regulates microglial M1/M2 polarization via the TLR4/NF-κB pathway to alleviate neuropathic pain

(Switching from the microglial M1 phenotype to the M2 phenotype is a promising therapeutic strategy for neuropathic pain (NP). This study aimed to investigate the potential use of stigmasterol for treating NP. In animal experiments, 32 male Sprague-Dawley rats were randomly divided into the sham operation group, chronic constriction injury (CCI) group, CCI + ibuprofen group, and CCI + stigmasterol group. We performed behavioral tests, enzyme-linked immunosorbent assay, hematoxylin-esoin staining (H&E) staining and immunohistochemistry, immunofluorescence, and Western blotting. In cell experiments, we performed flow cytometry, immunofluorescence, Western blotting, and qRT-PCR. Stigmasterol reduced thermal and mechanical hyperalgesia and serum IL-1β and IL-8 levels and increased serum IL-4 and TGF-β levels in CCI rats. Stigmasterol reduced IL-1β, COX-2, and TLR4 expression in the right sciatic nerve and IL-1β expression in the spinal cord. Stigmasterol reduced the expression of Iba-1, TLR4, MyD88, pNF-κB, pP38 MAPK, pJNK, pERK, COX-2, IL-1β, and CD32 in the spinal cord of CCI rats while increasing the expression of IL-10 and CD206. Stigmasterol decreased M1 polarization markers and increased M2 polarization markers in lipopolysaccharide (LPS)-induced microglia and decreased the expression of Iba-1, TLR4, MyD88, pNF-κB, pP38 MAPK, pJNK, pERK, iNOS, COX-2, and IL-1β in LPS-treated microglia while increasing the expression of Arg-1 and IL-10. Stigmasterol regulates microglial M1/M2 polarization via the TLR4/NF-κB pathway to alleviate NP.

Hydrogel and Nanomedicine-Based Multimodal Therapeutic Strategies for Spinal Cord Injury

Spinal cord injury (SCI) is a severe neurodegenerative disease caused by mechanical and biological factors, manifesting as a loss of motor and sensory functions. Inhibition of injury expansion and even reversal of injury in the acute damage stage of SCI are important strategies for treating this disease. Hydrogels and nanoparticle (NP)-based drugs are the most effective, widely studied, and clinically valuable therapeutic strategies in the field of repair and regeneration. Hydrogels are 3D flow structures that fill the pathological gaps in SCI and provide a microenvironment similar to that of the spinal cord extracellular matrix for nerve cell regeneration. NP-based drugs can easily penetrate the blood-spinal cord barrier, target SCI lesions, and are noninvasive. Hydrogels and NPs as drug carriers can be loaded with various drugs and biological therapeutic factors for slow release in SCI lesions. They help drugs function more efficiently by exerting anti-inflammatory, antioxidant, and nerve regeneration effects to promote the recovery of neurological function. In this review, the use of hydrogels and NPs as drug carriers and the role of both in the repair of SCI are discussed to provide a multimodal strategic reference for nerve repair and regeneration after SCI.

The identification of new roles for nicotinamide mononucleotide after spinal cord injury in mice: an RNA-seq and global gene expression study

Background

Nicotinamide mononucleotide (NMN), an important transforming precursor of nicotinamide adenine dinucleotide (NAD+). Numerous studies have confirmed the neuroprotective effects of NMN in nervous system diseases. However, its role in spinal cord injury (SCI) and the molecular mechanisms involved have yet to be fully elucidated.

Methods

We established a moderate-to-severe model of SCI by contusion (70 kdyn) using a spinal cord impactor. The drug was administered immediately after surgery, and mice were intraperitoneally injected with either NMN (500 mg NMN/kg body weight per day) or an equivalent volume of saline for seven days. The central area of the spinal cord was harvested seven days after injury for the systematic analysis of global gene expression by RNA Sequencing (RNA-seq) and finally validated using qRT-PCR.

Results

NMN supplementation restored NAD+ levels after SCI, promoted motor function recovery, and alleviated pain. This could potentially be associated with alterations in NAD+ dependent enzyme levels. RNA sequencing (RNA-seq) revealed that NMN can inhibit inflammation and potentially regulate signaling pathways, including interleukin-17 (IL-17), tumor necrosis factor (TNF), toll-like receptor, nod-like receptor, and chemokine signaling pathways. In addition, the construction of a protein-protein interaction (PPI) network and the screening of core genes showed that interleukin 1β (IL-1β), interferon regulatory factor 7 (IRF 7), C-X-C motif chemokine ligand 10 (Cxcl10), and other inflammationrelated factors, changed significantly after NMN treatment. qRT-PCR confirmed the inhibitory effect of NMN on inflammatory factors (IL-1β, TNF-α, IL-17A, IRF7) and chemokines (chemokine ligand 3, Cxcl10) in mice following SCI.

Conclusion

The reduction of NAD+ levels after SCI can be compensated by NMN supplementation, which can significantly restore motor function and relieve pain in a mouse model. RNA-seq and qRT-PCR systematically revealed that NMN affected inflammation-related signaling pathways, including the IL-17, TNF, Toll-like receptor, NOD-like receptor and chemokine signaling pathways, by down-regulating the expression of inflammatory factors and chemokines.

Linarin Protects Against CCl4-Induced Acute Liver Injury via Activating Autophagy and Inhibiting the Inflammatory Response: Involving the TLR4/MAPK/Nrf2 Pathway

Background

Linarin has been implicated in the inhibition of inflammatory responses and hepatoprotective effects. However, the precise mechanism by which Linarin integrates injury-induced signaling from inflammatory responses and oxidative stress remains unclear.

Methods

We evaluated the role of Linarin in a mouse model of carbon tetrachloride (CCl4)-induced acute liver injury. Mice were orally pretreated with Linarin or vehicle for seven consecutive days, followed by intraperitoneal injection with 0.2% (v/v) CCl4. To investigate the mechanism of action on oxidative stress, CCl4-stimulated HepG2 cells were utilized.

Results

Our results revealed Linarin remarkably attenuated the loss of hepatic architecture, inflammatory cell infiltration, serum transaminases, and pro-inflammatory cytokines induced by CCl4. Linarin attenuated CCl4-induced oxidative stress by increasing the expression of cytosolic Nrf2 (nuclear factor erythroid 2-related factor 2), inducing nuclear localization of Nrf2, and increasing stress-induced protein heme oxygenase-1 (HO-1). Additionally, Linarin decreased the expression of toll-like receptors (TLR)-4, and its downstream proteins, MyD88, IRAK1, and TRAF6. Furthermore, Linarin reversed CCl4-induced phosphorylation of ERK, p38, and JNK. Importantly, Linarin increased the expression of both LC3II and Beclin 1, which are hallmarks of autophagic flux. Autophagy-mediated hepatoprotective effects in Linarin-treated HepG2 cells were mitigated by the autophagy inhibitor 3-MA. However, combined treatment of Linarin with 3-MA failed to significantly reverse cell apoptosis and the production of transaminases and pro-inflammatory cytokines.

Conclusion

Linarin prevents acute liver injury, possibly by alleviating ROS-induced oxidative stress, inhibiting TLR4/MyD88 and JNK/p38/ERK-mediated inflammatory responses, and promoting Beclin 1/LC3II-mediated autophagic flux.

Study on the Mechanism of Eerdun Wurile's Effects on Post-operative Cognitive Dysfunction by the TLR4/NF-κB Pathway

The object of our work was to observe whether the Mongolian medicine Eerdun Wurile (EW) improve postoperative cognitive dysfunction (POCD) by affecting the TLR4/NF-κB. Mice (6-8-week-old male C57BL/6 J) were selected to establish an animal model of POCD by combining intracerebroventricular injection of lipopolysaccharide and nephrectomy; EW formulation and EW basic formulation were administered intra-gastrically for 7 consecutive days. The cognitive performance was assessed by Morris water maze test. H&E staining was examined to detect alterations in hippocampal tissue. Immunohistochemical staining was performed to evaluate MyD88, NF-κB, TLR4, iNOS, and IBA-1 expressions; Western blotting and RT-qPCR were performed to evaluate MyD88, NF-κB, and TLR4. The expressions of IL-6, IL-1β, and TNF-α were evaluated by ELISA. Intracerebroventricular injection of lipopolysaccharide combined with nephrectomy induced cognitive dysfunction in mice, stimulated TLR4/NF-κB and microglia, and promoted the secretion of murine TNF-α, IL-1β, and IL-6. EW formulation and EW basic formulation treatment are able to suppress the TLR4/NF-κB pathway activation and microglia, and the serum cytokine secretions related to proinflammation, and restore the cognitive performance. EW formulation and EW basic formulation can improve POCD in mice, and TLR4/NF-κB pathway seems to be one of the important mechanisms in EW's improvement of POCD.

FHL2 regulates microglia M1/M2 polarization after spinal cord injury via PARP14-depended STAT1/6 pathway

Neuronal apoptosis and inflammation exacerbate the secondary injury after spinal cord injury (SCI). Four and a half domains 2 (FHL2) is a multifunctional scaffold protein with tissue- and cell-type specific effects on the regulation of inflammation, but its role in SCI remains unclear. The T10 mouse spinal cord contusion model was established, and the mice were immediately injected with lentiviruses carrying FHL2 shRNA after SCI. The results showed that FHL2 expression was increased following SCI, and then gradually decreased. Moreover, FHL2 depletion aggravated functional impairment, neuronal necrosis, and enlarged lesion cavity areas in the injured spinal cord. FHL2 deficiency facilitated neuronal apoptosis by elevating cleaved caspase 3/9 expression, neuroinflammation by regulating microglia polarization, and bone loss. Indeed, FHL2 deficiency increased the secretion of TNF-α and IL-6, M1 microglia polarization, and the activation of STAT1 pathway but decreased the secretion of IL-10 and IL-4, M2 microglia polarization, and the activation of the STAT6 pathway in the spinal cord. In vitro, FHL2 silencing promoted LPS + IFN-γ-induced microglia M1 polarization through activating the STAT1 pathway and alleviated IL-4-induced microglia M2 polarization via inhibiting the STAT6 pathway. FHL2 positively regulated the expression of poly (ADP-ribose) polymerase family member 14 (PARP14) by promoting its transcription. PARP14 overexpression inhibited FHL2 silencing-induced microglia M1 polarization and relieved the inhibitory effect of FHL2 silencing on microglia M2 polarization. Collectively, the study suggests that FHL2 reduces the microglia M1/M2 polarization-mediated inflammation via PARP14-dependent STAT1/6 pathway and thereby improves functional recovery after SCI.

The Effects of Andrographis paniculata (Burm.F.) Wall. Ex Nees and Andrographolide on Neuroinflammation in the Treatment of Neurodegenerative Diseases

Neurodegenerative diseases (NDs) affect millions of people worldwide, and to date, Alzheimer's and Parkinson's diseases are the most common NDs. Of the many risk factors for neurodegeneration, the aging process has the most significant impact, to the extent that it is tempting to consider neurodegenerative disease as a manifestation of accelerated aging. However, genetic and environmental factors determine the course of neurodegenerative disease progression. It has been proposed that environmental stimuli influence neuroplasticity. Some clinical studies have shown that healthy lifestyles and the administration of nutraceuticals containing bioactive molecules possessing antioxidant and anti-inflammatory properties have a preventive impact or mitigate symptoms in previously diagnosed patients. Despite ongoing research efforts, the therapies currently used for the treatment of NDs provide only marginal therapeutic benefits; therefore, the focus is now directly on the search for natural products that could be valuable tools in combating these diseases, including the natural compound Andrographis paniculata (Ap) and its main constituent, andrographolide (Andro). Preclinical studies have shown that the aqueous extract of Ap can modulate neuroinflammatory and neurodegenerative responses, reducing inflammatory markers and oxidative stress in various NDs. Therefore, in this review, we will focus on the molecular mechanisms by which Ap and Andro can modulate the processes of neurodegeneration and neuroinflammation, which are significant causes of neuronal death and cognitive decline.

Aging and TNF induce premature senescence of astrocytes after spinal cord injury via regulating YAP expression

BACKGROUND

Spinal cord injury (SCI) causes chronic functional impairment in patients. In addition, SCI is tormenting more and more older adults, and those who suffer from SCI often have shorter lifespans. Previous studies have confirmed that overexpression of p75 leads to neuroinflammation and motor dysfunction following spinal cord injury in adult mice.

METHODS

As TNF-α is upregulated after SCI, targeting TNF-mediated inflammation may be an attractive option to combat trauma, paving the way for new therapeutic insight. In this study, we evaluated behavioral testing, phenotype of senescent cells, reactive oxygen species (ROS), inflammation and mitochondrial damage in adult (2-month-old) and aged (20-month-old) female wild-type (WT) and p75 knockout (KO) mice.

RESULTS

Herein, we hypothesized that aged mice were more prone to death after SCI, but p75 deletion could promote motor/sensory function recovery and improve survival in both adult and aged mice. Further exploration of the underlying mechanism revealed that the expression of p-YAP was reduced in vivo and in vitro, and p75 deletion partially rescued aging-induced astrocytes senescence.

CONCLUSION

Taken together, our study have identified an unrecognized function of the p75-YAP pathway on preventing astrocytic aging in vitro and in vivo, which may provide further insights and new targets into slowing spinal cord aging and improving dysfunctional remission and longevity.

Insight into the Neuroprotective Effect of Genistein-3'-Sodium Sulfonate Against Neonatal Hypoxic-Ischaemic Brain Injury in Rats by Bioinformatics

Therapeutic hypothermia (TH) is the only intervention approved for the treatment of neonatal hypoxic-ischaemic encephalopathy (HIE), but its treatment window is narrow (within 6 h after birth), and its efficacy is not ideal. Thus, alternative treatments are urgently needed. Our previous studies showed that genistein-3'-sodium sulfonate (GSS), a derivative of genistein (Gen), has a strong neuroprotective effect in rats with ischaemic stroke, but its role in HIE is unclear. A hypoxia-ischaemia (HI) brain injury model was established in neonatal male Sprague‒Dawley (SD) rats. Twenty-four hours after reperfusion, rats treated with GSS were assessed for cerebral infarction, neurological function, and neuronal damage. RNA-Seq and bioinformatics analysis were used to explore differentially expressed genes (DEGs) and regulated signalling pathways, which were subsequently validated by Western blotting and immunofluorescence. In this study, we found that GSS not only significantly reduced the size of brain infarcts and alleviated nerve damage in rats with HIE but also inhibited neuronal loss and degeneration in neonatal rats with HIE. A total of 2170 DEGs, of which 1102 were upregulated and 1068 were downregulated, were identified in the GSS group compared with the HI group. In an analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) categories, the downregulated DEGs were significantly enriched in the pathways "Phagosome", "NF-κB signalling", and "Complement and coagulation cascades", amongst others. Meanwhile, the upregulated DEGs were significantly enriched in the pathways "Neurodegeneration", "Glutamatergic synapse", and "Calcium signalling pathway", amongst others. These results indicate that GSS intervenes in the process of HIE-induced brain injury by participating in multiple pathways, which suggests potential candidate drugs for the treatment of HIE.

Surgical treatment of severe thoracic kyphosis and neurological deficit in a patient with Gorham–Stout syndrome: A case report and literature review

Background

Gorham–Stout syndrome is an uncommon condition with a varied clinical presentation and unclear cause that is characterised by a proliferation of lymphatic capillaries and severe regional osteolysis. Spinal and visceral involvement increases the syndrome's morbidity and mortality rates. Here, we report about a male patient with Gorham's disease who developed local kyphosis and neurological disorders due to massive osteolysis.

Case presentation

A 13-year-old male patient presented with progressive kyphosis and massive osteolysis of the thoracic vertebrae. Halo-pelvic traction and vertebral column resection osteotomy were performed to reconstruct the spine and prevent disease progression. The entire lesion was resected, and an artificial vertebra filled with allograft bone was used to achieve temporary stability. Although the patient presented with chylothorax following surgery, which required thoracic drainage, the patient did achieve a satisfying outcome.

Conclusions

Limited by the number of GSS cases with spinal involvement and chylothorax manifestations, halo-pelvic distraction as a preoperative preparation and vertebral column resection osteotomy provide a novel avenue for managing this disease.