Tetramethylpyrazine inhibits the inflammatory response by downregulating the TNFR1/IκB-α/NF-κB p65 pathway after spinal cord injury.

Previous studies have demonstrated that tetramethylpyrazine (TMP) can enhance the recovery of motor function in spinal cord injury (SCI) rats. However, the underlying mechanism involved in this therapeutic effect remains to be elucidated. We conducted RNA sequencing with a network pharmacology strategy to predict the targets and mechanism of TMP for SCI. The modified Allen's weight-drop method was used to construct an SCI rat model. The results indicated that the nuclear transfer factor-κB (NF-κB) pathway was identified through the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and an inflammatory response was identified through the Gene Ontology (GO) enrichment analysis. Tumor necrosis factor (TNF) was identified as a crucial target. Western blotting revealed that TMP decreased the protein expression of TNF superfamily receptor 1 (TNFR1), inhibitor κB-α (IκB-α), and NF-κB p65 in spinal cord tissues. Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) demonstrated that TMP inhibited TNF-α, interleukin-1ß (IL-1ß), reactive oxygen species (ROS), and malondialdehyde (MDA) expression and enhanced superoxide dismutase (SOD) expression. Histopathological observation and behavior assessments showed that TMP improved morphology and motor function. In conclusion, TMP inhibits inflammatory response and oxidative stress, thereby exerting a neuroprotective effect that may be related to the regulation of the TNFR1/IκB-α/NF-κB p65 signaling pathway.

A scoping review of functional near-infrared spectroscopy biomarkers in late-life depression: Depressive symptoms, cognitive functioning, and social functioning.

Late-life depression is one of the most damaging mental illnesses, disrupting the normal lives of older people by causing chronic illness and cognitive impairment. Patients with late-life depression, accompanied by changes in appetite, insomnia, fatigue and guilt, are more likely to experience irritability, anxiety and somatic symptoms. It increases the risk of suicide and dementia and is a major challenge for the public health systems. The current clinical assessment, identification and effectiveness assessment of late-life depression are primarily based on history taking, mental status examination and scale scoring, which lack subjectivity and precision. Functional near-infrared spectroscopy is a rapidly developing optical imaging technology that objectively reflects the oxygenation of hemoglobin in different cerebral regions during different tasks and assesses the functional status of the cerebral cortex. This article presents a comprehensive review of the assessment of functional near-infrared spectroscopy technology in assessing depressive symptoms, social functioning, and cognitive functioning in patients with late-life depression. The use of functional near-infrared spectroscopy provides greater insight into the neurobiological mechanisms underlying depression and helps to assess these three aspects of functionality in depressed patients. In addition, the study discusses the limitations of previous research and explores potential advances in the field.

[Experimental study of tetramethylpyrazine-loaded electroconductive hydrogel on angiogenesis and neuroprotection after spinal cord injury].

Objective: To explore the mechanisms for repairing spinal cord injury (SCI) with tetramethylpyrazine-loaded electroconductive hydrogel (hereinafter referred to as "TGTP"). Mehtods: A total of 72 female Sprague-Dawley rats were randomly divided into 4 groups: sham operation group (group A), SCI group (group B), SCI+electroconductive hydrogel group (group C), and SCI+TGTP group (group D). Only the vertebral plate was removed in group A, while the remaining groups were subjected to a whole transection model of spinal cord with a 2 mm gap in the lesions. The recovery of hindlimb motor function was evaluated by Basso, Beattie, Bresnahan (BBB) score and modified Rivlin-Tator inclined plate test before operation and at 1, 3, 7, 14, and 28 days after operation, respectively. Animals were sacrificed at 7 days and 28 days after modeling. Neovascularisation was observed by immunofluorescence staining of CD31 and the expression levels of angiopoietin 1 (Ang-1) and Tie-2 were assessed by Western blot assay. At 28 days postoperatively, the expression levels of pro-angiogenic related proteins, including platelet-derived growth factor B (PDGF-B), PDGF receptor ß (PDGFR-ß), vascular endothelial growth factor A (VEGF-A), and VEGF receptor 2 (VEGFR-2), were also assessed by Western blot. The fibrous scar in the injured area was assessed using Masson staining, while neuronal survival was observed through Nissl staining. Furthermore, LFB staining was utilized to detect myelin distribution and regeneration. Immunofluorescence and Western blot assay were employed to evaluate the expression of neurofilament 200 (NF200). Results: The hindlimb motor function of rats in each group gradually recovered from the 3rd day after operation. The BBB score and climbing angle in group D were significantly higher than those in group B from 3 to 28 days after operation, and significantly higher than those in group C at 14 days and 28 days after operation ( P<0.05). Masson staining showed that the collagen volume fraction in groups B-D were significantly higher than that in group A, and that in group D was significantly lower than that in groups B and C ( P<0.05); a small amount of black conductive particles were scattered at the broken end in group D, and the surrounding collagen fibers were less than those in group C. Nissl and LFB staining showed that the structure of neurons and myelin sheath in the injured area of spinal cord in group D was relatively complete and continuous, and the number of Nissl bodies and the positive area of myelin sheath in group D were significantly better than those in groups B and C ( P<0.05). NF200 immunofluorescence staining and Western blot assay results showed that the relative expression of NF200 protein in group D was significantly higher than that in groups B and C ( P<0.05). CD31 immunofluorescence staining showed that the fluorescence intensity of group D was better than that of groups B and C at 28 days after operation, and tubular or linear neovascularization could be seen. The relative expressions of Ang-1 and Tie-2 proteins in group D were significantly higher than those in groups B and C at 7 and 28 days after operation ( P<0.05). The relative expressions of PDGF-B and PDGFR-ß proteins in group D were significantly higher than those in groups B and C, and group B was significantly higher than group C at 28 days after operation ( P<0.05). The relative expressions of VEGF-A and VEGFR2 proteins in group D were higher than those in groups B and C, showing significant difference when compared with group B ( P<0.05), but only the expression of VEGF-A protein was significantly higher than that in group C ( P<0.05). There was significant difference only in VEGFR-2 protein between groups B and C ( P<0.05). Conclusion: TGTP may enhance the revascularization of the injured area and protect the neurons, thus alleviating the injury of spinal cord tissue structure and promoting the recovery of neurological function after SCI in rats.

Effect of use of NSAIDs or steroids during the acute phase of pain on the incidence of chronic pain: a systematic review and meta-analysis of randomised trials.

BACKGROUND: This study is the first to summarize the evidence on how the use of anti-inflammatory drugs during acute pain has an impact on the development of chronic pain. METHODS: Randomized controlled trials retrieved from nine databases included anti-inflammatory drugs (NSAIDs or steroids) versus non-anti-inflammatory drugs in patients with acute pain and reported the incidence of chronic pain. No specified date, age, sex, or language restrictions. Subgroup analyses were performed according to pain classification, follow-up time, and medication. The GRADE method was used to evaluate quality of evidence. RESULTS: A total of 29 trials (5220 patients) were included. Steroids or NSAIDs did not reduce the incidence of chronic nociceptive pain. Steroid use in acute phase significantly reduced the incidence of chronic neuropathic pain. In subgroup analysis, benefits were observed for methylprednisolone and dexamethasone, with some adverse effects. Steroids or NSAIDs were statistically significant in reducing pain intensity over 1 year, but the effect size was too small, and whether the long-term effect is clinically relevant needs to be further studied. CONCLUSION: Quality of the evidence was low to moderate. No drug can be recommended to prevent chronic nociceptive pain. Injections of steroids (methylprednisolone or dexamethasone) during the acute phase reduce the incidence of chronic neuropathic pain, but most included studies also used local anesthetics. The results are indirect and need to be interpreted with caution. The pooled data effect sizes for pain intensity were small, so the clinical relevance was unclear. Study registration PROSPERO (CRD42022367030).

Temporal profiling and validation of oxidative stress-related genes in spinal cord injury.

Oxidative stress (OS) plays a pivotal role in the pathogenesis of spinal cord injury (SCI), yet its underlying mechanisms remain elusive. In this study, we explored the OS phenotype in a rat model of SCI. Subsequently, comprehensive bioinformatic analyses were conducted on microarray data pertaining to SCI (GSE45006). Notably, KEGG enrichment analysis revealed a pronounced enrichment of pivotal pathways, namely MAPK, FoxO, Apoptosis, NF-κB, TNF, HIF-1, and Chemokine across distinct phases of SCI. Furthermore, GO enrichment analysis highlighted the significance of biological processes including response to hypoxia, response to decrease oxygen levels, response to reactive oxygen species, cellular response to oxidative stress, reactive oxygen species metabolic process, and regulation of neuron death in the context of OS following SCI. Notably, our study underscores the prominence of nine genes, namely Itgb1, Itgam, Fn1, Icam1, Cd44, Cxcr4, Ptprc, Tlr4, and Tlr2 as OS key genes in SCI, consistently expressed in both the acute phase (1, 3, 7 days) and sub-acute phase (14 days). Subsequently, the relative mRNA expression of these key genes in different time points (1, 3, 7, 14 days) post-SCI. Finally, leveraging the DsigDB database, we predicted ten potential compounds potentially targeting OS and facilitating the repair of SCI, thus providing novel insights into the mechanisms underlying OS and identifying potential therapeutic targets for SCI.

Early-stage effect of HIBD on neuro-motor function and organic composition of neurovascular units in neonatal rats.

Objective: This study aimed to investigate the effects of neonatal hypoxic-ischemic brain damage (HIBD) on early-stage neuro-motor function, cerebral blood flow, and the neurovascular unit. Methods: Twenty-four Sprague-Dawley newborn rats aged 7 days were obtained and randomly assigned to either the sham or the model group using a random number table. The HIBD model was established using the Rice-Vannucci method. After the induction of HIBD, the body weight of the rats was measured and their neuro-motor function was assessed. Further, cerebral blood flow perfusion was evaluated using laser speckle flow imaging, and immunofluorescent staining techniques were employed for examining the activation of specific markers and their morphological changes in different cell populations, which included vascular endothelial cells, neurons, astrocytes, and microglia within the motor cortex. Results: After HIBD, the model group exhibited impaired neuro-motor function and growth. Cerebral blood flow perfusion decreased in both the hemispheres on day 1 and in the ipsilateral brain on day 4. However, no significant difference was observed between the two groups on day 7. Moreover, the CD31 and NeuN showed a sharp decline on day 1, which was followed by a gradual increase in the expression levels. The activated microglia and astrocytes formed clusters in the injured cortex. Notably, the regions with positive staining for Arg-1, Iba-1, CD68, and GFAP consistently displayed higher values in the model group as compared to that in the sham group. The total number of branch endpoints and microglia branches was higher in the model group than in the sham group. Immunofluorescent co-localization analysis revealed no co-staining between Iba-1 and Arg-1; however, the Pearson's R-value for the co-localization of Iba-1 and CD68 was higher in the model group, which indicated an increasing trend of co-staining in the model group. Conclusion: Early-stage neuro-motor function, cerebral blood flow, microvasculature, and neurons in neonatal rats exhibited a trend of gradual recovery over time. The activation and upregulation of neuroglial cells continued persistently after HIBD. Furthermore, the impact of HIBD on early-stage neuro-motor function in newborn rats did not synchronize with the activation of neuroglial cells. The recovery of neuro-motor function, microvasculature, and neurons occurred earlier than that of neuroglial cells.

Granulocyte colony-stimulating factor effects on neurological and motor function in animals with spinal cord injury: a systematic review and meta-analysis.

Background: Spinal cord injury (SCI) is a severe neurological injury for which no effective treatment exists. Granulocyte colony-stimulating factor (G-CSF) is used to treat autologous bone marrow transplantation, chemotherapy-induced granulocytopenia, Acquired Immune Deficiency Syndrome (AIDS), etc. Recent research has revealed the potential application of G-CSF on neuroprotective effectiveness. In central nervous system diseases, G-CSF can be used to alleviate neuronal injury. Objective: To investigate the effects of G-CSF on Basso, Beattie, and Bresnahan (BBB) scale score, inclined plane test, electrophysiologic exam, quantitative analysis of TUNEL-positive cells, and quantitative analysis of glial fibrillary acidic protein (GFAP) immunostaining images in animal models of SCI. Methods: We searched PubMed, Web of Science, and Embase databases for all articles on G-CSF intervention with animal models of SCI reported before November 2022. A total of 20 studies met the inclusion criteria. Results: Results revealed that G-CSF intervention could improve the BBB scale score in both groups at 3, 7, 14, 28, and 35 days [at 35 days, weighted mean differences (WMD) = 2.4, 95% CI: 1.92-2.87, p < 0.00001, I2 = 69%]; inclined plane test score; electrophysiologic exam; quantitative analysis of TUNEL-positive cell numbers; quantitative analysis of GFAP immunostaining images in animal models of SCI. Subgroup analysis revealed that treatment with normal saline, phosphate-buffered saline, and no treatment resulted in significantly different neurological function effectiveness compared to the G-CSF therapy. SD rats and Wistar rats with SCI resulted in significant neurological function effectiveness. C57BL/6 mice showed no difference in the final effect. The T9-T10 or T10 segment injury model and the T8-T9 or T9 segment injury model resulted in significant neurological function effectiveness. The BBB score data showed no clear funnel plot asymmetry. We found no bias in the analysis result (Egger's test, p = 0.42). In our network meta-analysis, the SUCRA ranking showed that 15 mg/kg-20 mg/kg was an optimal dose for long-term efficacy. Conclusion: Our meta-analysis suggests that G-CSF therapy may enhance the recovery of motor activity and have a specific neuroprotective effect in SCI animal models.Systematic review registration: PROSPERO, identifier: CRD42023388315.

[Comparison of clinical efficacy between percutaneous endoscopic transforaminal discectomy and coblation nucleoplasty in the treatment of inclusive lumbar disc herniation].

OBJECTIVE: To observe clinical efficacy of percutaneous endoscopic transforaminal discectomy (PETD) and target radioffrequency thermal coblation nucleoplasty(CN) on inclusive lumbar disc herniation(LDH) in different age groups, and provide a basis for clinical formulation of precise and individualized treatments. METHODS: A retrospective analysis of 219 patients with lumbar disc herniation treated with PETD and CN between January 2018 and June 2021 was performed, in which 107 patients were treated with PETD and 112 with CN. Patients were stratified by age into young group(≤45 years old), middle-aged group(>45 years old and <60 years old) and older group(≥60 years old). Before treatment, 3 days, 1 month and 6 months after treatment, visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score, infrared thermal imaging temperature difference (△T) and lumbar range of motion (ROM) were evaluated and clinical efficacy were compared in the different age groups between two treatment methods. RESULTS: ①VAS and JOA score outcomes, in the same age group and the same treatment method, the VAS and JOA scores at different time points postoperatively were obviously improved (P<0.05). For the same age group and the different treatment methods, the older group had lower VAS and higher JOA scores after PETD than after CN (P<0.05), and there was no significant difference between the young group and middle-aged group (P>0.05). There was no significant difference in VAS and JOA scores at the same time between age groups by PETD treatment (P>0.05). The VAS was higher and the JOA score was lower in older group than in young group and middle-aged group at 1, 6 months after CN treatment(P<0.05). ②△T and ROM outcomes, in the same age group and same treatment method, postoperative △T and ROM at different time points were obviously improved(P<0.05). There was no significant difference in △T between two methods of PETD and CN at the same age(P>0.05), there was no significant difference in ROM between young group and middle-aged group(P>0.05), ROM was higher after PETD treatment than after CN treatment(P<0.05). There was no significant difference in △T and ROM at the same time between age groups by PETD treatment(P>0.05). There was no significant difference in △T between age groups by CN treatment, but the ROM was smaller in older group than in young group and middle-aged group after CN treatment(P<0.05). CONCLUSION: Both PETD and CN for inclusive LDH have good efficacy, the curative benefit for older patients receiving PETD within 6 months after surgery more than CN, and CN is more appropriate for young and middle-aged patients.

The Emerging Role of Neural Cell-Derived Exosomes in Intercellular Communication in Health and Neurodegenerative Diseases.

Intercellular communication in the central nervous system (CNS) is essential for brain growth, development, and homeostasis maintenance and, when dysfunctional, is involved in the occurrence and development of neurodegenerative diseases. Increasing evidence indicates that extracellular vesicles, especially exosomes, are critical mediators of intercellular signal transduction. Under physiological and pathological conditions, neural cells secret exosomes with the influence of many factors. These exosomes can carry specific proteins, lipids, nucleic acids, and other bioactive substances to the recipient cells to regulate their function. Depending on the CNS environment, as well as the origin and physiological or pathological status of parental cells, exosomes can mediate a variety of different effects, including synaptic plasticity, nutritional metabolic support, nerve regeneration, inflammatory response, anti-stress effect, cellular waste disposal, and the propagation of toxic components, playing an important role in health and neurodegenerative diseases. This review will discuss the possible roles of exosomes in CNS intercellular communication in both physiologic and neurodegenerative conditions.