Consideraciones bioéticas en el manejo de la esclerosis lateral amiotrófica: Una aproximación al quehacer fonoaudiológico

Introducción: La esclerosis lateral amiotrófica (ELA) es la forma más común de enfermedad degenerativa de motoneurona en la edad adulta y es considerada una enfermedad terminal. Por lo mismo, el accionar del fonoaudiólogo debe considerar el respeto a los principios bioéticos básicos para garantizar una asistencia adecuada. Objetivo: Conocer aquellas consideraciones bioéticas relacionadas al manejo y estudio de personas con ELA para luego brindar una aproximación hacia el quehacer fonoaudiológico. Método: Se efectuó una búsqueda bibliográfica en las bases de datos PubMed, Scopus y SciELO. Se filtraron artículos publicados desde 2000 hasta junio de 2023 y fueron seleccionados aquellos que abordaban algún componente bioético en población con ELA. Resultados: Aspectos relacionados al uso del consentimiento informado y a la toma de decisiones compartidas destacaron como elementos esenciales para apoyar la autonomía de las personas. Conclusión: Una correcta comunicación y una toma de decisiones compartida son claves para respetar la autonomía de las personas. A su vez, la estandarización de procedimientos mediante la investigación clínica permitirá aportar al cumplimiento de los principios bioéticos de beneficencia y no maleficencia, indispensables para la práctica profesional.

Introduction: Amyotrophic lateral sclerosis (ALS) is the most common form of degenerative motor neuron disease in adulthood and is considered a terminal disease. For this reason, the actions of the speech therapist must consider respect for basic bioethical principles to guarantee adequate assistance. Objective: To know those bioethical considerations related to the management and study of people with ALS to then provide an approach to speech therapy. Methodology: A bibliographic search was carried out in the PubMed, Scopus, and SciELO databases. Articles published from 2000 to June 2023 were filtered and those that addressed a bioethical component in the population with ALS were selected. Results: Aspects related to the use of informed consent and shared decision-making stood out as essential elements to support people's autonomy. Conclusion: Proper communication and shared decision-making are key to respecting people's autonomy. In turn, the standardization of procedures through clinical research will contribute to compliance with the bioethical principles of beneficence and non-maleficence, essential for professional practice.

Consensus from the Brazilian Academy of Neurology for the diagnosis, genetic counseling, and use of disease-modifying therapies in 5q spinal muscular atrophy / Consenso da Academia Brasileira de Neurologia para diagnóstico, aconselhamento genético e uso de terapias modificadoras na atrofia muscular espinhal 5q

Abstract Spinal muscular atrophy linked to chromosome 5 (SMA-5q) is an autosomal recessive genetic disease caused by mutations in the SMN1. SMA-5q is characterized by progressive degeneration of the spinal cord and bulbar motor neurons, causing severe motor and respiratory impairment with reduced survival, especially in its more severe clinical forms. In recent years, highly effective disease-modifying therapies have emerged, either acting by regulating the splicing of exon 7 of the SMN2 gene or adding a copy of the SMN1 gene through gene therapy, providing a drastic change in the natural history of the disease. In this way, developing therapeutic guides and expert consensus becomes essential to direct the use of these therapies in clinical practice. This consensus, prepared by Brazilian experts, aimed to review the main available disease-modifying therapies, critically analyze the results of clinical studies, and provide recommendations for their use in clinical practice for patients with SMA-5q. This consensus also addresses aspects related to diagnosis, genetic counseling, and follow-up of patients under drug treatment. Thus, this consensus provides valuable information regarding the current management of SMA-5q, helping therapeutic decisions in clinical practice and promoting additional gains in outcomes.

Resumo Atrofia muscular espinhal ligada ao cromossomo 5 (AME-5q) é uma doença genética de herança autossômica recessiva causada por mutações no gene SMN1. A AME-5q cursa com degeneração progressiva dos motoneurônios medulares e bulbares, acarretando grave comprometimento motor e respiratório com redução da sobrevida, especialmente nas suas formas clínicas mais graves. Nos últimos anos, terapias modificadoras da doença altamente eficazes, ou que atuam regulando o splicing do exon 7 do gene SMN2 ou adicionando uma cópia do gene SMN1 via terapia gênica, têm surgido, proporcionando uma mudança drástica na história natural da doença. Dessa forma, o desenvolvimento de guias terapêuticos e de consensos de especialistas torna-se importante no sentido de direcionar o uso dessas terapias na prática clínica. Este consenso, preparado por especialistas brasileiros, teve como objetivos revisar as principais terapias modificadoras de doença disponíveis, analisar criticamente os resultados dos estudos clínicos dessas terapias e prover recomendações para seu uso na prática clínica para pacientes com AME-5q. Aspectos relativos ao diagnóstico, aconselhamento genético e seguimento dos pacientes em uso das terapias também são abordados nesse consenso. Assim, esse consenso promove valiosas informações a respeito do manejo atual da AME-5q auxiliando decisões terapêuticas na prática clínica e promovendo ganhos adicionais nos desfechos finais.

Optimization and identification of a low density and high purity method for primary hippocampal neuron culture from fetal rats / 解剖学报

Objective To establish a low density, high purity and high stability in vitro culture method of primary hippocampal neurons of fetal rats by co-culturing hippocampal and cortical cells, so as to obtain higher purity and better vitality of primary hippocampal neurons disease. Methods The fetal rat hippocampal tissue was isolated from 16-18 days pregnant SD rats, then cut and digested by 0.125% trypsin. The obtained cell suspension was filtered by 200 mesh cell sieve, and then the obtained cell suspensions were then inoculated into the inner layer and outer ring of the culture plate in a surrounding form. They were co-cultured in DMEM/F12 medium containing 10% horse serum. After 4-6 hours of cell adhesion, the culture medium was changed to maintenance medium (Neurobasal+2% B27+0.5 mmol/L glutamine). Then the cell viability was detected with CCK-8 kit and the purity of hippocampal neurons was detected by immunofluorescent staining. Results Hippocampal neurons grew well and formed crisscross neural networks after 5 days. And it could survive for 3 weeks. The purity of hippocampal neurons was up to 98%. Conclusion The method of co-culturing hippocampal and cortical cells can obtain high-purity, high activity, high survival rate, and high stability primary hippocampal neurons from fetal rats, which can provide certain experimental conditions for the study of hippocampal neuron related diseases in the nervous system and is worthy of promotion and application.

Dynamic changes in cytoskeletal elements following acute cerebral ischemia and reperfusion in rats / 中国药理学通报

Aim To investigate the dynamic time-course changes in neuronal cytoskeleton after acute ischemia and reperfusion in rats. Methods Reperfusion was performedin rats by blocking the middle cerebralarteryfor 90 min, then therats wereobserved and collected at different time points. The brain damage wasobserved by Nissl staining,and neurobehavioural function was evaluated with neurological deficit score and forelimb placement test. The cellular changes in the alternations of cytoskeletal elements including microtubule associated protein 2 (MAP2) and neurofilament heavy chain (NF-H) were observed by immunohistochemistry staining and Western blot. Impaired axons, dendrites and cytoskeletal alternations were detected by electron microscope. Results Brain damage and neurobehavioural function were gradually aggravated with the prolongation of reperfusion. Brain damage appeared earlier and more severe in striatum than in cortex. Moreover, decreased MAP2-related and increased NF-H-related immunoreactive intensities were found in the ischemic areas. Impaired cytoskeletal arrangement and reduced dense were indicated. Damaged cytoskeletal components such as microtubules and neurofilament arrangement, decreased axonal filament density, and swelled dendrites were observed after cerebral ischemia reperfusion by ultrastructural observations. Conclusions Different brain regions have diverse tolerance to ischemia-reperfusion injury. Major elements of neuronal cytoskeleton show dynamic responses to ischemia and reperfusion, which may further contribute to brain damage and neurological impairment following MCAO and reperfusion.

Research progress of neuronal injury mediated by microglial activation and depression / 中国药理学通报

Depression is a common neurological disorder with high incidence, high recurrence and high disability, but its pathogenesis is unclear. In recent years, the protective and attacking effects of glial cells on neurons have become the frontier of neurological disease research. Neuronal injury caused by abnormal activation of microglia (MG) plays an important role in the pathogenesis of depression. In this paper, through literature retrieval by GeenMedical and CNKI, the relevant pathways and key targets of MG activation in depression are summarized so as to provide a theoretical basis for further clinical research.

Neuronomodulation of Excitable Neurons / 神经科学通报·英文版

Neuronomodulation refers to the modulation of neural conduction and synaptic transmission (i.e., the conduction process involved in synaptic transmission) of excitable neurons via changes in the membrane potential in response to chemical substances, from spillover neurotransmitters to paracrine or endocrine hormones circulating in the blood. Neuronomodulation can be direct or indirect, depending on the transduction pathways from the ligand binding site to the ion pore, either on the same molecule, i.e. the ion channel, or through an intermediate step on different molecules. The major players in direct neuronomodulation are ligand-gated or voltage-gated ion channels. The key process of direct neuronomodulation is the binding and chemoactivation of ligand-gated or voltage-gated ion channels, either orthosterically or allosterically, by various ligands. Indirect neuronomodulation involves metabotropic receptor-mediated slow potentials, where steroid hormones, cytokines, and chemokines can implement these actions. Elucidating neuronomodulation is of great significance for understanding the physiological mechanisms of brain function, and the occurrence and treatment of diseases.

A Novel Retrograde AAV Variant for Functional Manipulation of Cortical Projection Neurons in Mice and Monkeys / 神经科学通报·英文版

Retrograde adeno-associated viruses (AAVs) are capable of infecting the axons of projection neurons and serve as a powerful tool for the anatomical and functional characterization of neural networks. However, few retrograde AAV capsids have been shown to offer access to cortical projection neurons across different species and enable the manipulation of neural function in non-human primates (NHPs). Here, we report the development of a novel retrograde AAV capsid, AAV-DJ8R, which efficiently labeled cortical projection neurons after local administration into the striatum of mice and macaques. In addition, intrastriatally injected AAV-DJ8R mediated opsin expression in the mouse motor cortex and induced robust behavioral alterations. Moreover, AAV-DJ8R markedly increased motor cortical neuron firing upon optogenetic light stimulation after viral delivery into the macaque putamen. These data demonstrate the usefulness of AAV-DJ8R as an efficient retrograde tracer for cortical projection neurons in rodents and NHPs and indicate its suitability for use in conducting functional interrogations.

Wenyang Jieyu Prescription Regulates Hippocampal Neuron Apoptosis and Improves Synaptic Plasticity in Depressed Mice via BDNF/Akt/mTOR Pathway / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of Wenyang Jieyu prescription in regulating hippocampal neuron apoptosis and improving synaptic plasticity in the mouse model of depression induced by maternal separation combined with restraint stress. MethodThe mice on postnatal day 0 （PD0） were randomly assigned into a control group （n=10） and a modeling group （n=50）. Maternal separation combined with restraint stress was adopted to establish the mouse model of depression， and the modeled mice were randomized into model， Wenyang prescription， Jieyu prescription， Wenyang Jieyu prescription， and fluoxetine groups （n=10） on the weaning day （PD21）. From PD21 to PD111， the mice were fed with the diets mixed with corresponding medicines. The sucrose preference test， open field test， O-maze test， and novel object recognition test were then conducted to evaluate the depression， memory， and learning abilities of mice. Immunohistochemistry （IHC） was employed to measure the atomic absorbance （AA） of postsynaptic density protein 95 （PSD95） in the hippocampus. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to detect the apoptosis of hippocampal neurons. Western blot was employed to determine the protein levels of brain-derived neurotrophic factor （BDNF）， phosphorylated tyrosine kinase receptor B/tyrosine kinase receptor B （p-TrkB/TrkB）， phosphorylated protein kinase B/protein kinase B （p-Akt/Akt）， phosphorylated mammalian target of rapamycin/mammalian target of rapamycin （p-mTOR/mTOR）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X （Bax）， cysteinyl aspartate-specific proteinase-3 （Caspase-3）， synaptophysin （Syn）， and PSD95. ResultCompared with the control group， the modeling decreased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.01）. Furthermore， it decreased the expression of PSD95， increased the neuron apoptosis in the hippocampus （P<0.01）， down-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and up-regulated the protein levels of Bax and Caspase-3 （P<0.05） in the hippocampus. Compared with the model group， Wenyang Jieyu prescription and fluoxetine increased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.05， P<0.01）. Moreover， the drugs increased the expression of PSD95， reduced the neuron apoptosis （P<0.01）， up-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and down-regulated the protein levels of Bax and Caspase-3 （P<0.01）. ConclusionWenyang Jieyu prescription outperformed Wenyang prescription and Jieyu prescription in the treatment of the depressive behavior induced by maternal separation combined with restraint stress in mice. It exerted the therapeutic effect by reducing the hippocampal neuron apoptosis and improving the synaptic plasticity via the BDNF/Akt/mTOR pathway.

Noninvasive mechanical ventilation assistance in amyotrophic lateral sclerosis: a systematic review

ABSTRACT BACKGROUND: Respiratory failure is the most common cause of death in patients with amyotrophic lateral sclerosis (ALS), and morbidity is related to poor quality of life (QOL). Non-invasive ventilation (NIV) may be associated with prolonged survival and QOL in patients with ALS. OBJECTIVES: To assess whether NIV is effective and safe for patients with ALS in terms of survival and QOL, alerting the health system. DESIGN AND SETTING: Systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting standards using population, intervention, comparison, and outcome strategies. METHODS: The Cochrane Library, CENTRAL, MEDLINE, LILACS, EMBASE, and CRD databases were searched based on the eligibility criteria for all types of studies on NIV use in patients with ALS published up to January 2022. Data were extracted from the included studies, and the findings were presented using a narrative synthesis. RESULTS: Of the 120 papers identified, only 14 were related to systematic reviews. After thorough reading, only one meta-analysis was considered eligible. In the second stage, 248 studies were included; however, only one systematic review was included. The results demonstrated that NIV provided relief from the symptoms of chronic hypoventilation, increased survival, and improved QOL compared to standard care. These results varied according to clinical phenotype. CONCLUSIONS: NIV in patients with ALS improves the outcome and can delay the indication for tracheostomy, reducing expenditure on hospitalization and occupancy of intensive care unit beds. SYSTEMATIC REVIEW REGISTRATION: PROSPERO database: CRD42021279910 — https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=279910.

Study of Cerebellar Tissue Following Induction of Aging in Mice By Di-Galactose / Estudio del Tejido Cerebeloso tras la Inducción del Envejecimiento en Ratones por D-Galactosa

SUMMARY: The cerebellum is a crucial area of the hindbrain that plays an essential role in balancing, excitement control, and subtle and accurate functions. Studies have shown that long-term use of D-galactose in mice, as with the symptoms of aging, causes morphological and functional disorders in the brain. This study was performed to evaluate the changes in the cerebellum cortex tissue and the measurement of reactive oxygen species (ROS) in the cerebellum following the induction of aging in mice by D-galactose. Accordingly, subjects were randomly assigned into two groups: Normal saline group and Aging group (D-galactose). To create an aging model, D- galactose, and saline solution (sodium chloride 0.9 %) were used. After completing the preparation and passage of the tissue, the cerebellum specimens were cut in 5 microns thickness and then stained with hematoxylin-eosin stain and finally examined under a Nikon microscope. Quantitative variables were analyzed by SPSS software using T-test. In the observations of cerebellum tissue samples, in the aged induced group by D-galactose, the most changes were observed in the Neuron purkinjense (Purkinje cells) layer. In the observations of the cerebellum tissue samples of aging group induced by D-galactose, the most changes were observed in the Neuron purkinjense, and the arrangement and placement of these cells were disorientated. The nucleus positioning was not central, and the Neuron purkinjense induced by aging were seen in different morphological forms. Necrosis, Chromatolysis, and Pyknosis were found. Based on the results, D-galactose (induction of aging) causes pathological changes in the cerebellar cortex, especially in the Neuron purkinjense layer.

El cerebelo es un área crucial del rombencéfalo que desempeña un papel esencial en el equilibrio, el control de la excitación y las funciones sutiles y precisas. Los estudios han demostrado que el uso a largo plazo de D-galactosa en ratones, al igual que con los síntomas del envejecimiento, provoca trastornos morfológicos y funcionales en el cerebro. Este estudio se realizó para evaluar los cambios en el tejido de la corteza del cerebelo y la medición de especies reactivas de oxígeno (ROS) en el cerebelo luego de la inducción del envejecimiento en ratones por D-galactosa. En consecuencia, los sujetos fueron asignados aleatoriamente a dos grupos: grupo de solución salina normal y grupo de envejecimiento (D-galactosa). Para crear un modelo de envejecimiento, se utilizaron D-galactosa y solución salina (cloruro de sodio al 0,9 %). Después de completar la preparación y el paso del tejido, las muestras de cerebelo se cortaron en un grosor de 5 µm y luego se tiñeron con tinción de hematoxilina-eosina y finalmente se examinaron bajo un microscopio Nikon. Las variables cuantitativas se analizaron mediante el software SPSS utilizando la prueba T. En las observaciones de muestras de tejido de cerebelo, en el grupo envejecido inducido por D-galactosa, la mayoría de los cambios se observaron en la capa de neuronas purkinjenses (células de Purkinje). En las observaciones de las muestras de tejido del cerebelo del grupo de envejecimiento inducidas por D-galactosa, la mayoría de los cambios se observaron en las neuronas purkinjenses, y la disposición y ubicación de estas células estaban desorientadas. El posicionamiento del núcleo no era central y las neuronas purkinjenses inducidas por el envejecimiento se observaban en diferentes formas morfológicas. Se encontró necrosis, cromatólisis y picnosis. Según los resultados, la D-galactosa (inducción del envejecimiento) provoca cambios patológicos en la corteza cerebelosa, especialmente en la capa de neuronas purkinjenses.

Telehealth for amyotrophic lateral sclerosis in a multidisciplinary service in a Brazilian reference center / Telessaúde para esclerose lateral amiotrófica em um serviço multidisciplinar em um centro de referência brasileiro

Abstract Background Telehealth has been used in the treatment of different diseases, and it has been shown to provide benefits for patients with amyotrophic lateral sclerosis (ALS). Due to the social distancing measures put into effect during the coronavirus disease 2019 (COVID-19) pandemic, there was an urgent need for telehealth to ensure the provision of healthcare. Objective To evaluate the feasibility of telehealth for the provision of multidisciplinary ALS care, and to assess its acceptability among patients and caregivers. Methods We conducted a retrospective cohort study in which multidisciplinary evaluations were performed using the Teleconsulta platform. The patients included had ALS and at least one in-person clinical evaluation. The patients and the caregivers answered satisfaction questionnaires. Results The sample was composed of 46 patients, 32 male and 14 female subjects. The average distance from their residences to the reference services was of 115 km. Respiratory adjustment was the most addressed topic. Conclusion The strategy is viable and well accepted in terms of satisfaction. It was even more positive for patients in advanced stages of the disease or for those living far from the referral center.

Resumo Antecedentes A telessaúde tem sido utilizada no tratamento de diferentes doenças, e demonstrou-se que ela traz benefícios para pacientes com esclerose lateral amiotrófica (ELA). Devido às medidas de distanciamento social postas em prática durante a pandemia de doença do coronavírus 2019 (coronavirus disease 2019, COVID-19, em inglês), houve uma necessidade urgente de se usar a telessaúde para garantir a provisão dos cuidados de saúde. Objetivo Avaliar a viabilidade da telessaúde para a prestação de cuidados multidisciplinares na ELA, e verificar a sua aceitabilidade entre os pacientes e os cuidadores. Métodos Realizou-se um estudo de coorte retrospectivo, com avaliações multidisciplinares realizadas por meio da plataforma Teleconsulta. Os pacientes incluídos apresentavam ELA, e já haviam passado por pelo menos uma avaliação clínica presencial. Os pacientes e os cuidadores responderam a questionários de satisfação. Resultados A amostra continha 46 pacientes, 32 do sexo masculino e 14 do sexo feminino. A distância média de suas residências ao serviço de referência era de 115 km. O ajuste respiratório foi o tema mais abordado. Conclusão A estratégia é viável e bem-aceita em termos de satisfação. Foi ainda mais positiva para os pacientes com doença avançada ou residentes em uma cidade distante do centro de referência.

Expression changes and clinical significance of serum neuron-specific enolase and squamous cell carcinoma antigen in lung cancer patients after radiotherapy

Abstract Objective: To explore the changes and clinical significance of serum Neuron-Specific Enolase (NSE) and Squamous Cell Carcinoma antigen (SCC) in patients with lung cancer before and after radiotherapy. Methods: 82 patients with lung cancer were treated with radiotherapy, and effective clinical intervention was given during the radiotherapy process. The patients were followed up for 1 year after radiotherapy and were divided into a recurrence and metastasis group (n = 28) and a non-recurrence and metastasis group (n = 54) according to their prognosis. Another 54 healthy volunteers examined in the present study's hospital during the same period were selected as the control group. To compare the changes of NSE and SCC levels in serum in patients with lung cancer at admission and after radiotherapy, and to explore their clinical significance. Results: After intervention, NSE and SCC levels in the serum of the two groups of patients were significantly lower than those before intervention, and the levels of CD4+ and CD4+/CD8+ were significantly higher than those before intervention (p < 0.05); the level of CD8+ was not significantly different from that before intervention (p > 0.05). And NSE and SCC levels in the intervention group were significantly lower than those in the routine group, the levels of CD4+, CD4+/CD8+ were significantly higher than those in the routine group (p < 0.05). Conclusion: NSE and SCC in serum can preliminarily evaluate the effect of radiotherapy in patients with lung cancer and have a certain predictive effect on prognosis.

Mechanism of Gastrodia elata active ingredient reducing oxygen-glucose deprivation/reoxygenation injury in rat neuron / 中国药房

OBJECTIVE To study the improvement effect and mechanism of Gastrodia elata active ingredient 3，4- dihydroxybenzaldehyde （3，4-DD） on oxygen-glucose deprivation/reoxygenation（OGD/R） injury in rat primary brain microvascular endothelial cells （BMECs）-rat adrenal chromaffin cells PC12 co-culture system. METHODS The co-culture model of BMECs and PC12 cells was replicated in the Transwell chamber， and divided into control group， model group， butylphthalide group （positive control group， 0.1 mmol/L） and 3，4-DD group （0.1 μmol/L）. OGD/R injury model of the co-culture system was induced in those groups except for the control group. After preventively intervention in BMECs with relevant medicine or culture medium for 24 h， cell transendothelial electronic resistance （TEER） value， lactate dehydrogenase （LDH） activity， brain-derived neurotrophic factor （BDNF） level and mRNA expressions of TrkB， Plc-γ， Map-2， GAP-43 in PC12 cells was detected. RESULTS Compared with the control group， TEER of the co-culture model， LDH activity and BDNF level of PC12 cells were decreased significantly in the model group （P＜0.01）， while mRNA expressions of TrkB， Plc-γ， Map-2 and GAP-43 in PC12 cells were increased significantly （P＜0.01）. Compared with the model group， TEER of the co-culture model， LDH activity， BDNF level， and the mRNA expressions of TrkB， Plc-γ， Map-2 and GAP-43 in PC12 cells were increased significantly in the 3，4-DD group and butylphthalide group （P＜0.05 or P＜0.01）. CONCLUSIONS 3，4-DD can relieve the damage of neuronal OGD/R by acting on BMECs， the mechanism of which may be associated with activating the BDNF/TrkB signaling pathway.

Astragalin Inhibits Apoptosis of Cerebral Cortex Neurons in APP/PS1 Mice / 中山大学学报(医学科学版)

ObjectiveTo investigate the effect of Astragalin （AST） on apoptosis of cerebral cortex neurons in APP/PS1 transgenic mice. MethodsEighteen six-month-old male APP/PS1 transgenic mice were randomly divided into APP/PS1 group， APP/PS1+ 40 mg/kg AST group and APP/PS1+ 20 mg/kg Donepezil （DNP） group， with six mice in each group. At the same time， six male C57BL/6 mice were selected as the normal control group. After intraperitoneal injection of AST once a day and continuous administration for one month， we used Tunel staining to detect the apoptosis of neurons in the cerebral cortex of APP/PS1 mice； immunofluorescent staining to examine the expression of apoptosis-related proteins Bax， Bcl-2， Caspase9 and Cleaved-Caspase3 in the cerebral cortex neurons of APP/PS1 mice； Western blot method to evaluate the changes of the expression of Bax， Bcl-2， Caspase9 and Caspase3. ResultsTunel staining showed that 40 mg/kg AST and 20 mg/kg DNP both reduced the apoptosis of neurons in the cerebral cortex of APP/PS1 mice， AST with more significant inhibition effect. Immunofluorescent staining revealed that 40 mg/kg AST and 20 mg/kg DNP both inhibited the expression of Bax， Caspase9， and Cleaved-Caspase3， and icreased the expression of Bcl-2 in the cerebral cortex neurons of APP/PS1 mice. Western blot results further confirmed that 40 mg/kg AST and 20 mg/kg DNP both down-regulated the expression of Bax （P < 0.05， P < 0.05）， Caspase9 （P < 0.005， P < 0.05） and Caspase3 （P < 0.0001， P < 0.0001） ， and up-regulated the expresstion of Bcl-2 （P < 0.05， P < 0.05） in the cerebral cortex neurons of APP/PS1 mice. ConclusionsAST can inhibit the apoptosis of cerebral cortex neurons in APP/PS1 mice.

Protective effect and mechanism of baicalein on hypoxia-induced cortical neuron injury in rats / 中国药房

OBJECTIVE To explore the protective effect and possible mechanism of baicalein on hypoxia-induced cortical neuron injury in rats. METHODS The cortical neurons of rats （RN-C cells） were studied and cultured under hypoxic conditions （5%CO2， 94% N2， 1%O2） for 24 hours； the effects of different concentrations of baicalein （0.01， 0.1， 1， 10， 100 μmol/L） on the survival rate of hypoxic RN-C cells were investigated； the effects of baicalein （0.1 μmol/L） on the activities of lactate dehydrogenase （LDH） and superoxide dismutase （SOD）， the content of malondialdehyde （MDA）， migration rate， apoptotic rate， cell cycle and the expressions of cleaved caspase-3， B-cell lymphoma-2 （Bcl-2） and Bcl-2 X protein （Bax） were all detected. RESULTS Compared with control group， the survival rate of cells in the hypoxia group was significantly reduced （P＜0.01）； 0.01， 0.1 and 1 μmol/L baicalein could reverse survival rate of hypoxia-induced cortical neurons （P＜0.05 or P＜0.01）. Scratch experiments showed that baicalein significantly increased the migration rate of hypoxic RN-C cells （P＜0.01）. Compared with control group， the activity of LDH in the supernatant and the content of MDA in the cells， apoptotic rate and the proportion of cells in G1 phase， were significantly increased in the hypoxia group， while SOD activity and the proportion of cells in G2+S phase was decreased significantly （P＜0.01）. The protein expressions of cleaved caspase-3 were increased significantly， while the ratio of Bcl-2/Bax in cells was significantly reduced （P＜0.05 or P＜0.01）. Compared with hypoxia group， the above indexes were all reversed significantly in baicalein group （P＜0.01）. CONCLUSIONS Baicalein can promote the proliferation and migration of cortical neurons， improve hypoxia-induced cell apoptosis and cell cycle distribution， decrease the activity of LDH in supernatant and the level of cellular lipid peroxidation， and improve antioxidant levels. Its mechanism may be related to regulating the caspase- 3/Bax/Bcl-2 pathway.

Expression changes of NaV channel subunits correlate with developmental maturation of electrophysiological characteristics of rat cerebellar Purkinje neurons / 南方医科大学学报

OBJECTIVE@#To investigate the variations in the expression of voltage-gated sodium (Nav) channel subunits during development of rat cerebellar Purkinje neurons and their correlation with maturation of electrophysiological characteristics of the neurons.@*METHODS@#We observed the changes in the expression levels of NaV1.1, 1.2, 1.3 and 1.6 during the development of Purkinje neurons using immunohistochemistry in neonatal (5-7 days after birth), juvenile (12-14 days), adolescent (21-24 days), and adult (42-60 days) SD rats. Using whole-cell patch-clamp technique, we recorded the spontaneous electrical activity of the neurons in ex vivo brain slices of rats of different ages to analyze the changes of electrophysiological characteristics of these neurons during development.@*RESULTS@#The expression of NaV subunits in rat cerebellar Purkinje neurons showed significant variations during development. NaV1.1 subunit was highly expressed throughout the developmental stages and increased progressively with age (P < 0.05). NaV1.2 expression was not detected in the neurons in any of the developmental stages (P > 0.05). The expression level of NaV1.3 decreased with development and became undetectable after adolescence (P < 0.05). NaV1.6 expression was not detected during infancy, but increased with further development (P < 0.05). NaV1.1 and NaV1.3 were mainly expressed in the early stages of development. With the maturation of the rats, NaV1.3 expression disappeared and NaV1.6 expression increased in the neurons. NaV1.1 and NaV1.6 were mainly expressed after adolescence. The total NaV protein level increased gradually with development (P < 0.05) and tended to stabilize after adolescence. The spontaneous frequency and excitability of the Purkinje neurons increased gradually with development and reached the mature levels in adolescence. The developmental expression of NaV subunits was positively correlated with discharge frequency (r=0.9942, P < 0.05) and negatively correlated with the excitatory threshold of the neurons (r=0.9891, P < 0.05).@*CONCLUSION@#The changes in the expression levels of NaV subunits are correlated with the maturation of high frequency electrophysiological properties of the neurons, suggesting thatmature NaV subunit expressions is the basis of maturation of electrophysiological characteristics of the neurons.

Clinical profile of genetically confirmed Spinal Muscular Atrophy (SMA) Among Filipino children less than 18 years old

@#Spinal muscular atrophy (SMA) is the most common inherited lethal disease in children. Confirmatory diagnosis is based on molecular genetic testing of survival motor neuron (SMN) genes. We aimed to describe the phenotypic presentation of Filipino infants and children with SMA based on the copy number analysis of SMN genes. Medical records of 17 Filipino children were reviewed from January 2017 to December 2019. De-identified clinical data fulfilled the diagnostic criteria defined by the International SMA Consortium. Among Filipino children, the predominant SMA type by copy number was type I having two copies of SMN2 gene. The clinical severity based on symptom onset and highest functional motor capacity attained correlated with SMN2 copy number congruent with existing data. A significant time lag between symptom onset to confirmation of genetic diagnosis was noted. Nine out of the 17 (52%) children did not have a family history of the disease, raising the possibility of mutation carriers in these families since the incidence of de novo mutations in literature is about 2%. These data offered the first epidemiological pattern of genetically confirmed SMA among Filipino children; provided additional information for genetic counselling; and an avenue to consider pre-symptomatic newborn screening and carrier testing that would change proactive measures and opportunities for therapy. These measures unavoidably will decrease the incidence and prevalence of disease in the future.

Protective effect of proanthocyanidins on neurotoxicity of benzoapyrene / 环境与职业医学

Background Benzo[a]pyrene (BaP) is neurotoxic and can cause neuronal damage by oxidative stress. Proanthocyanidin (PC) has antioxidant activity, and its mechanism may related to nuclear factor-erythroid 2-related factor 2 (Nrf2)-heme oxygenase-1 (HO-1) signaling pathway. Objective To explore potential protective effect of PC on hippocampal neuron injury induced by BaP oxidative stress. Methods Hippocampal neurons of neonatal SD rats delivered within 24 h were isolated and cultured, and cell activity was detected by cell counting kit-8 (CCK-8) method. According to the pre-experimental results, a control group and three BaP groups of 10, 20 and 40 µmol·L−1 were set up for Stage I experiment. The length of neurites and number of branches of hippocampal neurons in each group were observed by immunofluorescence method. Reactive oxygen species (ROS) fluorescence probe method was used to measure ROS levels in cells. Real-time quantitative fluorescent polymerase chain reaction (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression of Nrf2, Kelch-like epichlorohydrin associated protein-1 (Keap1), HO-1, B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X (Bax) in hippocampal neurons of each group, respectively. According to the results of Stage I experiment, three group were set up, including control group, BaP alone treatment group (BaP 20 µmol·L−1), and PC intervention group (BaP 20 µmol·L−1 + PC 2.5 µg·mL−1) for Stage II experiment, with the same protocol as Stage I. Results For Stage I experiment, compared with the control group, the 10, 20, and 40 µmol·L−1 BaP groups showed gradually shortened length of neurites [(177.60±3.49), (142.40±6.52), and (100.50±19.40) µm] (P<0.05) and decreased number of branches (8.00±1.00, 6.33±1.53, 4.33± 0.58) of hippocampal neurons (P<0.05); increased ROS production (2.38±0.33, 8.08±0.26, 9.86±0.19) (P<0.05); the qRT-PCR results showed that the mRNA expression levels of Nrf2 (0.35±0.03, 0.25±0.01, 0.13±0.03), Keap1 (0.70±0.01, 0.47±0.03, 0.15±0.02), HO-1 (0.77±0.02, 0.60±0.02, 0.32±0.01), and Bcl-2 (0.65±0.03, 0.47±0.02, 0.18±0.02) gradually decreased, and the mRNA expression level of Bax gradually increased (1.24±0.01, 2.25±0.15, 4.98±0.30) (P<0.05); the Western blotting results showed that the protein expression trends of Nrf2, Keap1, HO-1, Bcl-2, and Bax were consistent with the mRNA results. For Stage II experiment, compared with the BaP alone treatment group, the length of neurites in the PC intervention group became longer, (149.90±3.01) μm vs (202.00±4.45) μm (P<0.05), the number of branches increased, (4.67±0.58) vs (8.33±0.58) (P<0.05); the ROS production reduced, (10.81±0.63) vs (7.31±0.70) (P<0.05); the mRNA expression levels of Nrf2, Keap1, HO-1, and Bcl-2 increased (P<0.05), and the mRNA expression levels of Bax decreased (P<0.05); the Nrf2, Keap1, HO-1, and Bcl-2 protein expression levels increased (P<0.05), and Bax protein expression level decreased (P<0.05). Conclusion PC may exert neuroprotective effects by activating the Nrf2-HO-1 signaling pathway, inhibiting BaP-induced oxidative stress in neuronal cells, and reducing cytotoxicity.

7,8-dihydroxy-9,10-epoxybenzoapyrene induced ferroptosis in mouse hippocampal neuron HT22 cells and its mechanism / 环境与职业医学

Background Benzo[a]pyrene (BaP) has neurotoxicity, which can induce the loss of hippocampal neurons in humans and animals and lead to spatial learning and memory dysfunction, but its mechanism is still unclear. Objective To observe the ferroptosis of mouse hippocampal neuron HT22 cells induced by 7,8-dihydroxy-9,10-epoxybenzo[a]pyrene (BPDE), an active metabolite of BaP, and to explore its potential mechanism, so as to provide a basis for the study of BaP neurotoxicity mechanism. Method Mouse hippocampal neuron HT22 cells were selected and divided into four groups: solvent control group and low, medium, and high concentration BPDE exposure groups (0.25, 0.50, and 0.75 μmol·L−1). Cell survival was detected by CCK8 method. Cell morphology and ultrastructure were observed under light and electron microscopes. The levels of reactive oxygen species (ROS) and Fe2+ were detected by fluorescence probe method. Iron, 4-hydroxynonenoic acid (4-HNE), malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase (GSH-PX) levels were detected with commercial kits. The expression levels of acyl-CoA synthase long chain family member 4 (ACSL4), cyclooxygenase 2 (COX2), solute carrier family 7 member 11 (SLC7A11), and glutathione peroxidase 4 (GPX4) were detected by Western blotting. After interventions with ferroptosis inhibitors 20 μmol·L−1 deferoxamine (DFO) and 10 μmol·L−1 ethyl 3-amino-4-cyclohexylaminobenzoate (Fer-1), the cell survival rate of each BPDE exposure group and the changes of the ferroptosis characteristic indicators and protein expression levels were observed. Results With the increase of BPDE concentration, the survival rate of HT22 cells decreased gradually, and the survival rate of each BPDE group was significantly lower than that of the solvent control group (P<0.01). Under light microscope, the number of cells in the high concentration BPDE group was significantly reduced, and atrophic cells and reduced synapses were recorded. Under electron microscope, the HT22 cells in the high concentration BPDE group showed mitochondrial shrinkage, decreased crista, and increased mitochondrial membrane density. Compared with the solvent control group, the levels of intracellular lipid ROS, Fe2+, 4-HNE, and MDA significantly increased in the high concentration group (P<0.01), the GSH and GSH-PX levels were significantly decreased (P<0.01), the protein expression levels of ASCL4 and COX2 were significantly increased (P<0.01), and the protein expression levels of SCL7A11 and GPX4 were significantly decreased (P<0.01). The ferroptosis inhibitors DFO and Fer-1 significantly reversed the cell survival rate (P<0.01), the ferroptosis characteristic indicators (ROS, Fe2+, 4-HNE, MDA, GSH, and GSH-PX levels) (P<0.01), and the expression levels of ferroptosis-related proteins (ACSL4, COX2, SLC7A11, and GPX4) (P<0.01) in the high concentration BPDE group. Conclusion BPDE can induce ferroptosis in mouse hippocampal neuron HT22 cells, which may be related to the inhibition of SLC7A11/GSH/GPX4 axis and the induction of iron metabolism disorder.

Astrocytes in Chronic Pain: Cellular and Molecular Mechanisms / 神经科学通报·英文版

Chronic pain is challenging to treat due to the limited therapeutic options and adverse side-effects of therapies. Astrocytes are the most abundant glial cells in the central nervous system and play important roles in different pathological conditions, including chronic pain. Astrocytes regulate nociceptive synaptic transmission and network function via neuron-glia and glia-glia interactions to exaggerate pain signals under chronic pain conditions. It is also becoming clear that astrocytes play active roles in brain regions important for the emotional and memory-related aspects of chronic pain. Therefore, this review presents our current understanding of the roles of astrocytes in chronic pain, how they regulate nociceptive responses, and their cellular and molecular mechanisms of action.