Electroacupuncture Promotes Functional Recovery after Facial Nerve Injury in Rats by Regulating Autophagy via GDNF and PI3K/mTOR Signaling Pathway / 中国结合医学杂志

OBJECTIVE@#To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway.@*METHODS@#Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR.@*RESULTS@#The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01).@*CONCLUSIONS@#EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.

Expression of GDNF and AR in Testicular Peritubular Cells of Surgery-induced Cryptorchidism Mice / 中山大学学报(医学科学版)

ObjectiveTo investigate the expression of glial cell line-derived neurotrophic factor （GDNF） and androgen receptor （AR） in testicular peritubular cells （TPCs） of cryptorchidism mouse models and explore the theoretical significance of cryptorchidism-induced spermatogenesis dysfunction. MethodsA total of 30 five-week-old male ICR rats were divided randomly by using random number table method into 6 groups. Cryptorchidism was surgically induced in 3 randomly selected groups and the other 3 groups underwent sham surgery as the control groups. On days 4， 7 and 14 after surgery， we harvested the mice testes of the 3 groups and their corresponding control groups， then measured the testicular volumes， analyzed the testicular histopathology and detected the mRNA and protein expression levels of AR and GDNF in TPCs by immunofluorescence， real-time PCR and Western blot. ResultsIn normal control groups， on days 4， 7 and 14 after surgery， the testicular volumes were （125.58±19.22） mm3，（123.45±20.12） mm3， （140.09±13.62） mm3 ， respectively. Clear layers of spermatogenic cells were well arranged and abundant sperm cells were found. Peritubular cells were morphologically homogeneous， with slim-spindle appearance and normal cell thickness. The mRNA expression levels of AR were 1.00±0.05， 1.06±0.07 and 1.19±0.13； GDNF mRNA 1.00±0.04， 1.09±0.05， and 1.10±0.07. The protein expression levels of AR were 1.01±0.01， 0.79±0.02 and 1.01±0.04； GDNF protein （18.68±0.43） pg/mL， （14.39±0.36） pg/mL and （16.88±0.37） pg/mL. In cryptorchidism groups， on days 4， 7 and 14 after surgery， the testicular volumes were （115.64±3.91） mm3， （69.51±14.97） mm3 and （44.86±5.56） mm3， respectively. Spermatogenic cells were disorganized， seminiferous tubules were disrupted， peritubular cells shrank， bent and fractured. The mRNA expression levels of AR were 0.76±0.06， 0.53±0.04， and 0.29±0.02； GDNF mRNA 0.72±0.05， 0.42±0.02 and 0.30±0.03. The protein expression levels of AR were 0.54±0.02， 0.98±0.04 and 0.31±0.01； GDNF protein （8.50±0.34） pg/mL， （17.44±0.32） pg/mL and （6.83±0.34） pg/mL. Statistically significant differences （P < 0.05） were found in 7-day and 14-day testicular volumes between control and cryptorchidism groups but not in the 4-day testicular volume （P > 0.05）. Testicular volumes， AR and GDNF mRNA and protein expression in control groups had no statistically significant difference （P > 0.05）， while those in cryptorchidism groups showed a trend of gradual decline in the amount and the differences between groups were statistically significant （P < 0.05）. ConclusionsIn surgery-induced cryptorchidism mice， after the induction， the expression of AR and GDNF in TPCs showed a gradual decrease over time. AR and GDNF play a major role in mediating the TPCs damage in cryptorchidism. This study provides a theoretical basis for mechanism researches of cryptorchidism-induced spermatogenesis dysfunction.

Research progress of retinal neurovascular unit injury in glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

Glaucoma is one of the leading causes of vision loss worldwide. More and more studies have suggested that glaucoma is a complicated retinal neurovascular disease. The homeostasis imbalance of retinal neurovascular unit(RNVU)composed of neurons, glial cells and microvascular cells not only induces changes in microvascular structure and glial cells, but also affects the nerve tissue of the retina, resulting in vision loss, which there is no effective treatment to reverse, currently. Exploring the cellular composition and molecular structure of RNVU and investigating the destruction mechanism of normal cellular environment and intercellular connections in glaucoma are of great significance in exploring the pathogenesis and the treatment of glaucoma. The research progress on structural changes and dysfunction of RNVU in glaucoma are reviewed, hoping to provide new ideas for the treatment of glaucoma.

Effect of Mingjing Granules on Fibrovascular Membrane of Wet Age-related Macular Degeneration Based on Macrophages and Glial Cells / 中国实验方剂学杂志

ObjectiveTo investigate the effects of Mingjing granules （MJKL） on the fibrovascular membrane of experimental wet age-related macular degeneration （nAMD） based on macrophages and glial cells and further explain the mechanism of MJKL in the treatment of nAMD. MethodThe experimental nAMD fibrovascular membrane model was established by two-stage laser photocoagulation. BN rats were randomly divided into three groups： model group， anti-vascular endothelial growth factor （VEGF） group， and MJKL + anti-VEGF group. The model group was given distilled water for intragastric administration. Anti-VEGF group was injected with leizumab injection in the vitreous cavity. MJKL + anti-VEGF group was injected with leizumab injection in the vitreous cavity， and MJKL was intragastrically administered. Ten normal BN rats were not modeled and fed as controls. After 40 days of model making， fundus lesion morphology， lesion exudation area， and MD value were observed by fundus photography （FP）， fundus angiography （FFA）， optical coherence tomography （OCT）， and retinal pigment epithelium （RPE）-choroid-sclera film. The changes in retinal structure were observed by histopathology， and the expression and distribution of F4/80， Iba-1， and GFAP were detected by immunofluorescence. The relative expression levels of F4/80， Iba-1， and GFAP mRNA were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultThe fibrovascular membrane model was established 40d after two-stage laser modeling. The lesion exudation area， MD value， lesion height， and lesion area in the anti-VEGF group were significantly lower than those in the model group （P<0.05）， and the retinal structural damage degree was significantly improved. Compared with the anti-VEGF group， the MJKL + anti-VEGF group significantly decreased the MD value， lesion height， and lesion area （P<0.05）， and lesion area and retinal structural damage degree were significantly improved. The fluorescence intensity of F4/80 and Iba-1 in the model group was significantly higher than that in the normal group （P<0.05）， and that in the anti-VEGF group was significantly lower than that in the model group （P<0.05）. The fluorescence intensity in the MJKL + anti-VEGF group was significantly lower than that in the anti-VEGF group （P<0.05）. The fluorescence intensity of GFAP in the model group was significantly higher than that in the normal group （P<0.05）， and that in the anti-VEGF group was significantly lower than that in the model group （P<0.05）. The relative expression levels of F4/80， Iba-1， and GFAP mRNA in the model group were significantly increased compared with the normal group （P<0.05）， and the anti-VEGF group was significantly decreased compared with the model group （P<0.05）. The relative expression levels of F4/80， Iba-1， and GFAP mRNA in the MJKL + anti-VEGF group were significantly decreased compared with those in the anti-VEGF group （P<0.05）. ConclusionMJKL combined with anti-VEGF drugs can inhibit the growth of experimental nAMD fibrovascular membrane better than anti-VEGF drugs alone， and the mechanism may be related to inhibiting the participation of macrophages and glial cells in the formation of fibrovascular membrane.

Changes to GFAP Immunoreactive Astrocytes in Medial Prefrontal Cortex Following Exposure to Chronic Stress and Antioxidant Supplementation in Rat Model

@#Introduction: Astrocytes are responsible for many essential functions of neurons in CNS. It has been recognised that chronic stress affects the morphology of astrocyte. Natural antioxidant such as honey has been used as one of the therapeutic strategies to lessen the damaging effect of chronic stress on our body. Therefore, the aim of the study is to explore the effect of natural antioxidant, Tualang honey (TH) on the morphology of astrocytes following chronic stress exposure. Methods: Thirty-two male rats were randomly divided into the 4 groups: (i) control, (ii) stress, (iii) honey, (iv) stress plus honey groups.TH was administered via oral gavage at dose of 1.0 g/kg body weight pre and post experiment. Chronic stress was exposed to animals in group (ii) and (iv) for consecutive 21 days. Anti GFAP immunohistochemistry method was employed to label astrocytes in the medial prefrontal cortex. The number of GFAP+ astrocytes and several parameters related to astrocyte processes were measured. Results: The present study showed that chronic stress reduced the GFAP immunoreactive astrocyte number and percentage of GFAP immunoreactive material. Chronic stress also caused a reduction in astrocyte process ramification as indicated by a reduction in astrocyte total number of processes, average length of processes and maximum number of intersections. However, antioxidant treatment using TH could not reverse these stress-induced changes to the astrocytes. Conclusion: These results demonstrate that chronic stress decreases the number of GFAP immunoreactive astrocyte and cause shrinking of astrocyte processes in stress-sensitive brain region, but these changes cannot be reversed by antioxidant treatment.

The effects of transcranial magnetic stimulation on the expression of P2X7R and GFAP in the prefrontal cortex and hippocampus of mice modeling chronic depression / 中华物理医学与康复杂志

Objective:To investigate any effect of repeated transcranial magnetic stimulation (rTMS) on the expression of P2X7 receptor (P2X7R) and glial fibrillary acid protein (GFAP) in the prefrontal cortex and hippocampus of mice modeling depression.Methods:Thirty C57BL/6 mice were divided into a control group ( n=10) and a depression group ( n=20). The mice of the control group were raised in group (five mice per cage), while those of the depression group were kept alone for six weeks to induce depression. Among them, 16 were successfully modeled and randomly divided into a model group ( n=8) and an rTMS group ( n=8). The rTMS group received five sessions per week of 10Hz rTMS for 4 weeks. Any changes in depression-like behavior were observed and the expression of P2X7R and GFAP in the prefrontal cortex and hippocampus was measured. Results:Compared to the control group, a significant decrease was observed in the sucrose consumption rate in the sucrose preference test, in the distance moved in the open field test and in the expression of GFAP protein. But there was a significant increase in the immobile time in the tail suspension test and in the expression of P2X7R protein in the prefrontal cortex and hippocampus in the model group. At the conclusion of the experiment the differences in the sucrose consumption rate, the distance moved, GFAP protein expression, immobile time and P2X7R protein expression between the rTMS and the model group were all statistically significant.Conclusion:rTMS can reduce depression-like behavior, at least in mice. That may be related to inhibiting P2X7R expression and promoting GFAP expression in the prefrontal cortex and hippocampus.

Autoimmune glial fibrillary acidic protein astrocytopathy / 中华神经科杂志

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a rare immune-mediated inflammatory disease of central nervous system reported in recent years, and its specific biological marker is anti-GFAP autoantibody. In this paper, the etiology, pathogenesis, clinical manifestations, auxiliary examination and treatment of the disease are comprehensively expounded, so as to improve the understanding of clinicians, especially neurologists.

Progress of major biomarkers for neonatal brain injury in clinical application / 国际儿科学杂志

With the continuous progress of monitoring and treatment skills, the mortality of neonates has gradually decreased, and the long-term neurodevelopmental outcome has become the primary concern of society and families.During the perinatal period, the developing brain is vulnerable to hypoxia, hemorrhage, infection and inflammation, which may cause varying degrees of brain cell damage.Studies have found that proteins released by damaged brain cells can be detected in the body fluid of neonates, which are related to the occurrence and prognosis of neonatal brain injury.This article mainly reviews the recently reported brain injury biomarkers such as S100B, neuron specific enolase(NSE)and glial fibrillary acidic protein(GFAP)in different biological samples and its clinical predictive value for the occurrence of brain injury and neurodevelopmental prognosis.

Effects of volatile oil from Acori graminei Rhizoma on glial fibrillary acidic protein, c-Jun N-terminal protein kinase and tumor necrosis factor-α expressions in the spinal cord dorsal horn of the inflammatory pain rats / 解剖学报

Objective To investigate the influence of volatile oil from Acori graminei Rhizoma (VOA) on expressions of glial fibrillary acidic protein (GFAP), c-Jun N-terminal protein kainse (JNK) and tumour necrosis factor-α (TNF-α) in the spinal cord dorsal horn of imflammatory pain rats. Methods Totally 36 male SD rats were randomly divided into control group (control), sham-operated group (sham), complete Freund' s adjuvant group (CFA), 5 g/(kg·d) low dose VOA+CFA group (VOA-L+CFA), 10 g/(kg·d) medium dose VOA + CFA group (VOA-M+CFA) and 20 g/(kg·d) high dose VOA + CFA group (VOA-H+CFA). All animals were sacrificed immediately after continuous gavage administration for 22 days. The expressions of GFAP, JNK and TNF-α in the spinal cord dorsal horn of rats in each group were detected by immunofluorescence and Western blotting methods. Results The present results showed that the positive expressions of GFAP, JNK and TNF-α in the spinal cord dorsal horn of rats increased significantly in the CFA group, when compared to the control and sham groups (P < 0. 01). The expressions of GFAP, JNK and TNF-α in the spinal cord dorsal horn of rats with VOA treatment reduced in the dose-dependent manner, when compared to the CFA group, the positive expressions of GFAP, JNK and TNF-α reduced significantly in the dorsal horn of the spinal cord of the VOA-H+CFA group (P<0. 05, P<0. 01). Conclusion VOA reduces the expressions of GFAP, JNK and TNF-α in the spinal cord dorsal horn of rats of CFA-induced inflammatory pain.

Research on cellular damages and astrocyte activation after cerebral ischemia and reperfusion / 中国药理学通报

Aim To observe cellular damage and astrocyte activation at different time points of cerebral ischemia and reperfusion. Methods The middle cerebral artery of male SpragueDawley rats was occluded for 90 min followed by different time points of reperfusion. Eighty-five SPF male SD rats were randomly divided into control group (Sham), IR3, 6, 12, 24 and IR48h (MCAO followed by 48 h of reperfusion) group. Cerebral ischemia and reperfusion injury was observed by HE staining, and the structure of astrocytes was estimated with transmission electron microscopy (TEM). GFAP expression was detected by immunofluorescence staining and Western blot. Results Cerebral ischemia following by different time points of reperfusion led to different degrees of cellular damage, which was the most serious at 24 h of reperfusion. TEM showed destruction of astrocytes structure, swollen organelles and broken mitochondrial ridge. After cerebral ischemia-reperfusion, the expression levels of GFAP were significant up-regulated in the ischemic penumbra cortex and the highest was at 48 h of reperfusion, indicating astrocytes were activated. In addition, the results showed the gradual decrease in GFAP expression in the infarct core. Conclusions After cerebral ischemia-reperfusion, cellular damage is aggravated, and astrocytes are gradually activated in the ischemic penumbra. With the extension of reperfusion time, the boundaries of infarct area and ischemic area are gradually clear, and scarring may occur.

Effects of delayed ramelteon treatment on neurological function and tissue repair after cryogenic traumatic brain injury / 中国药理学通报

:Aim To study the effects of continuous dai¬ly administration of ramelteon starting at the subacute period of cryogenic traumatic brain injury (cTBI) on neurological function and brain tissue repair in mice. Methods Thirty male C57BL/6 mice were randomly divided into sham group, vehicle group and ramelteon treatment groups. The right sensory-motor cortex was damaged by pressing a copper probe precooled by liq¬uid nitrogen onto the skull. Ramelteon ( 10 nig 'kg-1 • d"1) was administered by gavage every day starting at different time points after cTBI (1 h, 1 d,3 d) until sacrifice on day 14. Beam walking test and open field test were used to evaluate the motor function. Toluidine blue staining was used to measure the infarct volume. Immunofluorescence was used to detect the expression of GAP-43 and synaptophysin in peri-infarct area. Mi¬croglia activation was detected using Iba-1. The area and thickness of glial scars were analyzed by detecting GFAP positive areas. Results All three treatment ( 1 h - 14 d, 1 - 14 d, and 3 - 14 d) significantly im¬proved cTBI induced motor dysfunction, reduced the infarct volume, elevated the expression of GAP -43 and synaptophysin, and decreased the area and thick¬ness of glial scar and microglia activation. In addition, all ramelteon treatment groups had similar effects on the above indexes. Conclusions Delayed ramelteon treatment can improve neurological dysfunction after cTBI,and the therapeutic time window can be delayed for up to three days after cTBI. Inhibiting glial scar formation and microglia activation, and promoting ax- onal regeneration and synaptogenesis may contribute to the beneficial effects of ramelteon.

Single-cell profiling reveals Müller glia coordinate retinal intercellular communication during light/dark adaptation via thyroid hormone signaling

Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination. Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation. However, various types of neurons and glial cells exist in the retina, and whether and how all retinal cells interact to adapt to light/dark conditions at the cellular and molecular levels requires systematic investigation. Therefore, we utilized single-cell RNA sequencing to dissect retinal cell-type-specific transcriptomes during light/dark adaptation in mice. The results demonstrated that, in addition to photoreceptors, other retinal cell types also showed dynamic molecular changes and specifically enriched signaling pathways under light/dark adaptation. Importantly, Müller glial cells (MGs) were identified as hub cells for intercellular interactions, displaying complex cell‒cell communication with other retinal cells. Furthermore, light increased the transcription of the deiodinase Dio2 in MGs, which converted thyroxine (T4) to active triiodothyronine (T3). Subsequently, light increased T3 levels and regulated mitochondrial respiration in retinal cells in response to light conditions. As cones specifically express the thyroid hormone receptor Thrb, they responded to the increase in T3 by adjusting light responsiveness. Loss of the expression of Dio2 specifically in MGs decreased the light responsive ability of cones. These results suggest that retinal cells display global transcriptional changes under light/dark adaptation and that MGs coordinate intercellular communication during light/dark adaptation via thyroid hormone signaling.

Effects of specific knockdown of ribosomal protein S5 in hepatic stellate cells on liver fibrosis / 药学实践杂志

Objective To observe the effect of specific knockdown of hepatic stellate cells (HSC) ribosomal protein S5 (RPS5) on liver fibrosis in rats. Methods The glial fibrillary acidic protein (GFAP) promoter-driven RPS5 shRNA adenovirus was established, and AdGFa2-shRPS5 and its control AdGFa2 shNC were used to transfect primary rat HSCs and hepatocytes, respectively. RPS5 was determined by Western-blot and Real Time PCR, α-SMA and type I collagen expression; the rat liver fibrosis model was established by dimethyl nitrosamine (DMN) and bile duct ligation (BDL), and intrahepatic HSC was specifically knocked down by tail vein injection of adenovirus of RPS5 levels. The pathological changes of liver tissue sections were analyzed by HE staining; the content of hydroxyproline, sections of Sirius red and Masson staining were used to evaluate collagen deposition; immunohistochemical staining was used to detect the expression of α-SMA and RPS5. Results AdGFa2-shRPS5 specifically knocked down the expression level of RPS5 in HSC and increased the expression of α-SMA and type I collagen in vitro. The in vivo results showed that in two animal models of chronic liver injury, specific knockdown of RPS5 expression in HSCs promoted HSC activation, increased the deposition of extracellular matrix, and promoted liver fibrosis. Conclusion RPS5 is essential for HSC activation and liver fibrosis, which could be a potential target for the treatment of liver fibrosis.

Glia Connect Inflammation and Neurodegeneration in Multiple Sclerosis / 神经科学通报·英文版

Multiple sclerosis (MS) is regarded as a chronic inflammatory disease that leads to demyelination and eventually to neurodegeneration. Activation of innate immune cells and other inflammatory cells in the brain and spinal cord of people with MS has been well described. However, with the innovation of technology in glial cell research, we have a deep understanding of the mechanisms of glial cells connecting inflammation and neurodegeneration in MS. In this review, we focus on the role of glial cells, including microglia, astrocytes, and oligodendrocytes, in the pathogenesis of MS. We mainly focus on the connection between glial cells and immune cells in the process of axonal damage and demyelinating neuron loss.

Updated Understanding of the Glial-Vascular Unit in Central Nervous System Disorders / 神经科学通报·英文版

The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.

Interactions Between Astrocytes and Oligodendroglia in Myelin Development and Related Brain Diseases / 神经科学通报·英文版

Astrocytes (ASTs) and oligodendroglial lineage cells (OLGs) are major macroglial cells in the central nervous system. ASTs communicate with each other through connexin (Cx) and Cx-based network structures, both of which allow for quick transport of nutrients and signals. Moreover, ASTs interact with OLGs through connexin (Cx)-mediated networks to modulate various physiological processes in the brain. In this article, following a brief description of the infrastructural basis of the glial networks and exocrine factors by which ASTs and OLGs may crosstalk, we focus on recapitulating how the interactions between these two types of glial cells modulate myelination, and how the AST-OLG interactions are involved in protecting the integrity of the blood-brain barrier (BBB) and regulating synaptogenesis and neural activity. Recent studies further suggest that AST-OLG interactions are associated with myelin-related diseases, such as multiple sclerosis. A better understanding of the regulatory mechanisms underlying AST-OLG interactions may inspire the development of novel therapeutic strategies for related brain diseases.

Immunological Markers for Central Nervous System Glia / 神经科学通报·英文版

Glial cells in the central nervous system (CNS) are composed of oligodendrocytes, astrocytes and microglia. They contribute more than half of the total cells of the CNS, and are essential for neural development and functioning. Studies on the fate specification, differentiation, and functional diversification of glial cells mainly rely on the proper use of cell- or stage-specific molecular markers. However, as cellular markers often exhibit different specificity and sensitivity, careful consideration must be given prior to their application to avoid possible confusion. Here, we provide an updated overview of a list of well-established immunological markers for the labeling of central glia, and discuss the cell-type specificity and stage dependency of their expression.

Spatiotemporal Dynamics of the Molecular Expression Pattern and Intercellular Interactions in the Glial Scar Response to Spinal Cord Injury / 神经科学通报·英文版

Nerve regeneration in adult mammalian spinal cord is poor because of the lack of intrinsic regeneration of neurons and extrinsic factors - the glial scar is triggered by injury and inhibits or promotes regeneration. Recent technological advances in spatial transcriptomics (ST) provide a unique opportunity to decipher most genes systematically throughout scar formation, which remains poorly understood. Here, we first constructed the tissue-wide gene expression patterns of mouse spinal cords over the course of scar formation using ST after spinal cord injury from 32 samples. Locally, we profiled gene expression gradients from the leading edge to the core of the scar areas to further understand the scar microenvironment, such as neurotransmitter disorders, activation of the pro-inflammatory response, neurotoxic saturated lipids, angiogenesis, obstructed axon extension, and extracellular structure re-organization. In addition, we described 21 cell transcriptional states during scar formation and delineated the origins, functional diversity, and possible trajectories of subpopulations of fibroblasts, glia, and immune cells. Specifically, we found some regulators in special cell types, such as Thbs1 and Col1a2 in macrophages, CD36 and Postn in fibroblasts, Plxnb2 and Nxpe3 in microglia, Clu in astrocytes, and CD74 in oligodendrocytes. Furthermore, salvianolic acid B, a blood-brain barrier permeation and CD36 inhibitor, was administered after surgery and found to remedy fibrosis. Subsequently, we described the extent of the scar boundary and profiled the bidirectional ligand-receptor interactions at the neighboring cluster boundary, contributing to maintain scar architecture during gliosis and fibrosis, and found that GPR37L1_PSAP, and GPR37_PSAP were the most significant gene-pairs among microglia, fibroblasts, and astrocytes. Last, we quantified the fraction of scar-resident cells and proposed four possible phases of scar formation: macrophage infiltration, proliferation and differentiation of scar-resident cells, scar emergence, and scar stationary. Together, these profiles delineated the spatial heterogeneity of the scar, confirmed the previous concepts about scar architecture, provided some new clues for scar formation, and served as a valuable resource for the treatment of central nervous system injury.

Clinical features of autoimmune glial fibrillary acidic protein astrocytopathy in children: an analysis of 34 cases / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features of children with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A).@*METHODS@#A retrospective analysis was performed on the medical data of 34 children with GFAP-A who attended the Department of Neurology, Children's Hospital of Chongqing Medical University, from January 2020 to February 2022. The medical data included clinical manifestations, cerebrospinal fluid features, imaging examination results, treatment, and prognosis.@*RESULTS@#The median age of onset was 8.4 (range 1.9-14.9) years for the 34 children with GFAP-A. The main clinical manifestations included headache (50%, 17/34), fever (47%, 16/34), visual impairment (47%, 16/34), and disturbance of consciousness (44%, 15/34). Abnormal cerebrospinal fluid results were observed in 19 children (56%, 19/34), among whom 8 children had positive autoantibody. The children with overlap syndrome had significantly higher recurrence rate and rate of use of immunosuppressant than those without overlap syndrome (P<0.05). About 77% (24/31) of the children had good response to immunotherapy, and only 1 child had poor prognosis.@*CONCLUSIONS@#Children with GFAP-A often have non-specific clinical symptoms and show good response to immunotherapy. Children with overlap syndrome have a high recurrence rate, and early application of immunosuppressants may help to prevent recurrence and alleviate symptoms.

Neuroprotective effect of tetramethylpyrazine on mice after spinal cord injury / 中国中药杂志

This study aims to investigate the neuroprotective effect of tetramethylpyrazine on mice after spinal cord injury and its mechanism. Seventy-five female C57BL/6 mice were randomly divided into 5 groups, namely, a sham operation group, a model group, a tetramethylpyrazine low-dose group(25 mg·kg~(-1)), a tetramethylpyrazine medium-dose group(50 mg·kg~(-1)), and a tetramethylpyrazine high-dose group(100 mg·kg~(-1)), with 15 mice in each group. Modified Rivlin method was used to establish the mouse model of acute spinal cord injury. After 14 d of tetramethylpyrazine intervention, the motor function of hind limbs of mice was evaluated by basso mouse scale(BMS) and inclined plate test. The levels of inflammatory cytokines tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-1β(IL-1β) in the spinal cord homogenate were determined by enzyme-linked immunosorbent assay(ELISA). Hematoxylin-eosin(HE) staining was used to observe the histology of the spinal cord, and Nissl's staining was used to observe the changes in the number of neurons. Western blot and immunofluorescence method were used to detect the expression of glial fibrillary acidic protein(GFAP) and C3 protein. Tetramethylpyrazine significantly improved the motor function of the hind limbs of mice after spinal cord injury, and the BMS score and inclined plate test score of the tetramethylpyrazine high-dose group were significantly higher than those of the model group(P<0.01). The levels of TNF-α, IL-6, and IL-1β in spinal cord homogenate of the tetramethylpyrazine high-dose group were significantly decreased(P<0.01). After tetramethylpyrazine treatment, the spinal cord morphology recovered, the number of Nissl bodies increased obviously with regular shape, and the loss of neurons decreased. As compared with the model group, the expression of GFAP and C3 protein was significantly decreased(P<0.05,P<0.01) in tetramethylpyrazine high-dose group. In conclusion, tetramethylpyrazine can promote the improvement of motor function and play a neuroprotective role in mice after spinal cord injury, and its mechanism may be related to inhibiting inflammatory response and improving the hyperplasia of glial scar.