Nerve Degeneration

神经退化
  • 文章类型: Journal Article
    目的:使用光学相干断层扫描(OCT),我们评估了乳头周围视网膜神经纤维之间的关联,黄斑厚度,黄斑神经节细胞内丛状层,和抗药性。
    方法:在这项横断面研究中,我们招募了被诊断为癫痫患者和健康对照者.癫痫患者根据他们对抗癫痫药物的反应被进一步分层为耐药或非耐药。进行OCT测量,并分析了右眼的发现。
    结果:51名耐药参与者,37不耐药,纳入45名对照。平均乳头周围视网膜神经纤维层,神经节细胞内丛状层,癫痫组的黄斑厚度比对照组薄。耐药组的平均神经节细胞内丛状层厚度(p=0.004)和异常/临界GC/IPL厚度的比例(p=5.40E-04)明显低于非耐药组。然而,视网膜周围神经纤维平均厚度与黄斑厚度无明显差异。这三个参数的时间部分在耐药组中也明显比非耐药组中薄。在多元回归模型中,耐药性是神经节细胞内丛状厚度降低的独立预测因素(几率OR=10.25,95%CI2.82~37.28)。癫痫发作频率增加(r=-0.23,p=0.039)和使用过的抗癫痫药物数量增加(r=-0.27,p=0.013)与神经节细胞内丛状层厚度呈负相关。
    结论:耐药癫痫患者的平均神经节细胞内丛状层厚度和颞部视网膜周围神经纤维层和黄斑厚度一致降低。这表明神经节细胞内丛状层厚度可能作为耐药性负担的指标,
    结论:在我们的研究中,我们使用了一种称为OCT的特殊工具来测量癫痫患者和健康对照者的视网膜厚度。我们发现,与健康对照相比,癫痫患者的所有区域的视网膜始终更薄。特别是,在对药物没有反应的组中,一个称为神经节细胞内丛状层的特定层要薄得多,这种减少与癫痫发作的频率和服用多少药物有关。此外,耐药组中视网膜的某些部分较薄.
    OBJECTIVE: Using Optical coherence tomography (OCT), we evaluated the association between peripapillary retinal nerve fiber, macular thickness, macular ganglion cell-inner plexiform layer, and drug resistance.
    METHODS: In this cross-sectional study, we recruited people diagnosed with epilepsy and healthy controls. People with epilepsy were further stratified as drug-resistant or non-drug-resistant based on their response to anti-seizure medications. OCT measurements were conducted, and findings in right eye were analyzed.
    RESULTS: Fifty-one drug-resistant participants, 37 non-drug-resistant, and 45 controls were enrolled. The average peripapillary retinal nerve fiber layer, ganglion cell-inner plexiform layer, and macular thickness were thinner in the epilepsy groups than in controls. The drug-resistant group had significantly lower average ganglion cell-inner plexiform layer thickness (p = 0.004) and a higher proportion of abnormal/borderline GC/IPL thickness (p = 5.40E-04) than the non-drug-resistant group. Nevertheless, no significant differences were seen between the average thickness of peripapillary retinal nerve fiber and macular thickness. The temporal sectors of these three parameters were also significantly thinner in the drug-resistant group than in the non-drug-resistant. In a multivariate regression model, drug resistance was an independent predictor of reduced ganglion cell-inner plexiform thickness (Odds ratios OR = 10.25, 95% CI 2.82 to 37.28). Increased seizure frequency (r = -0.23, p = 0.039) and a higher number of anti-seizure medications ever used (r = -0.27, p = 0.013) were negatively associated with ganglion cell-inner plexiform layer thickness.
    CONCLUSIONS: Individuals with drug-resistant epilepsy had a consistent reduction in average ganglion cell-inner plexiform layer thickness and the temporal sector of peripapillary retinal nerve fiber layer and macular thickness. This suggests that ganglion cell-inner plexiform layer thickness could potentially serve as an indicator of the burden of drug resistance, as it correlated with reduced thickness in individuals having more frequent seizures and greater exposure to ASMs.
    CONCLUSIONS: In our study, we used a special tool called OCT to measure how thick the retina is in people with epilepsy and in healthy control. We found that the retina was consistently thinner in all areas for those with epilepsy compared to healthy control. Particularly, a specific layer called the ganglion cell-inner plexiform layer was a lot thinner in the group that didn\'t respond to medications, and this thinning was related to how often seizures occurred and how much medications were taken. Also, certain parts of the retina were thinner in the drug-resistant group.
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  • 文章类型: Journal Article
    背景:血管失调是青光眼的主要危险因素之一,内皮素-1(ET-1)可能在血管性青光眼的发病机制中起作用。枸杞果实提取物(LB)在各种动物模型中表现出抗衰老和保护视网膜神经节细胞(RGC)的多靶点机制。探讨LB糖蛋白(LbGP)在ET-1诱导的RGC变性中的疗效,在预处理和后处理条件下将LbGP应用于ET-1小鼠模型。使用基于临床的技术表征视网膜结构和功能结果。
    方法:将成年C57BL/6小鼠随机分为四个实验组,即车辆控制(n=9),LbGP预处理(n=8),LbGP-后处理(第1天)(n=8)和LbGP-后处理(第5天)(n=7)。每天一次口服施用lmg/Kg的LbGP或用于载体对照的PBS。治疗前和治疗后(第1天或第5天)在玻璃体内注射前1周和后1或5天开始,分别,并持续到注射后第28天。使用光学相干断层扫描(OCT)评估治疗对视网膜结构和功能的影响,基线时多普勒OCT和视网膜电图测量,注射后第10天和第28天。通过在视网膜整体上使用RBPMS免疫染色来评估RGC存活。
    结果:在媒介物对照中注射ET-1引起动脉流量和视网膜功能的短暂减少,在第28天导致显著的RNFL变薄和RGC损失。尽管在所有LbGP组中ET-1引起血流或视网膜功能的短暂丧失,与载体对照相比,LbGP治疗促进更好地恢复视网膜血流和视网膜功能。此外,所有三个LbGP治疗组(即从第1天或第5天的治疗前和治疗后)均显著保留了RNFL厚度和RGC密度。在三个LbGP治疗组之间没有观察到保护作用的显著差异。
    结论:LbGP在ET-1诱导的RGC变性小鼠模型中显示出神经保护作用,将治疗作为预处理,立即或延迟后治疗。LbGP治疗促进了视网膜血流的更好恢复,并保护了RNFL,RGC密度和视网膜功能。这项研究显示了LB作为青光眼治疗的补充治疗的转化潜力。
    BACKGROUND: Vascular dysregulation is one of the major risk factors of glaucoma, and endothelin-1 (ET-1) may have a role in the pathogenesis of vascular-related glaucoma. Fruit extract from Lycium Barbarum (LB) exhibits anti-ageing and multitarget mechanisms in protecting retinal ganglion cells (RGC) in various animal models. To investigate the therapeutic efficacy of LB glycoproteins (LbGP) in ET-1 induced RGC degeneration, LbGP was applied under pre- and posttreatment conditions to an ET-1 mouse model. Retina structural and functional outcomes were characterised using clinical-based techniques.
    METHODS: Adult C57BL/6 mice were randomly allocated into four experimental groups, namely vehicle control (n = 9), LbGP-Pretreatment (n = 8), LbGP-Posttreatment (day 1) (n = 8) and LbGP-Posttreatment (day 5) (n = 7). Oral administration of LbGP 1 mg/Kg or PBS for vehicle control was given once daily. Pre- and posttreatment (day 1 or 5) were commenced at 1 week before and 1 or 5 days after intravitreal injections, respectively, and were continued until postinjection day 28. Effects of treatment on retinal structure and functions were evaluated using optical coherence tomography (OCT), doppler OCT and electroretinogram measurements at baseline, post-injection days 10 and 28. RGC survival was evaluated by using RBPMS immunostaining on retinal wholemounts.
    RESULTS: ET-1 injection in vehicle control induced transient reductions in arterial flow and retinal functions, leading to significant RNFL thinning and RGC loss at day 28. Although ET-1 induced a transient loss in blood flow or retinal functions in all LbGP groups, LbGP treatments facilitated better restoration of retinal flow and retinal functions as compared with the vehicle control. Also, all three LbGP treatment groups (i.e. pre- and posttreatments from days 1 or 5) significantly preserved thRNFL thickness and RGC densities. No significant difference in protective effects was observed among the three LbGP treatment groups.
    CONCLUSIONS: LbGP demonstrated neuroprotective effects in a mouse model of ET-1 induced RGC degeneration, with treatment applied either as a pretreatment, immediate or delayed posttreatment. LbGP treatment promoted a better restoration of retinal blood flow, and protected the RNFL, RGC density and retinal functions. This study showed the translational potential of LB as complementary treatment for glaucoma management.
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  • 文章类型: Editorial
    暂无摘要。
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  • 文章类型: Journal Article
    先前的研究已经证明了蓝斑(LC)在睡眠-觉醒调节中的重要性。特发性震颤(ET)和帕金森病(PD)都有共同的睡眠障碍,例如差的睡眠质量(QoS)。LC病理学是这两种疾病的特征。出现了关于LC退化对不良QoS发生的贡献的问题。
    评估ET和PD患者LC损害与睡眠障碍之间的关系。
    共有83例ET患者,124与PD,并招募83名健康个体,根据个体匹兹堡睡眠质量指数(PSQI)评分分为有/无QoS差的ET/PD(Sle/NorET和Sle/NorPD)亚组。进行了神经黑色素敏感磁共振成像(NM-MRI)和来自扩散MRI的游离水成像。随后,我们评估了ET和PD组LC的对比噪声比(CNRLC)和LC的自由水值(FWLC)与PSQI评分之间的相关性.
    CNRLC在ET(p=0.047)和PD(p=0.018)中明显低于健康个体,而各组间FWLC无显著差异。在多次比较校正后,有/没有睡眠障碍的患者之间的CNR/FWLC没有观察到显着差异。ET和PD患者的CNR/FWLC与PSQI之间无相关性。
    在ET和PD患者中均观察到LC变性,暗示其参与两种疾病的病理生理学。此外,LC完整性和PSQI之间没有观察到显著关联,这表明LC损伤可能与整体QoS没有直接关系。
    UNASSIGNED: Previous studies have demonstrated the importance of the locus coeruleus (LC) in sleep-wake regulation. Both essential tremor (ET) and Parkinson\'s disease (PD) share common sleep disorders, such as poor quality of sleep (QoS). LC pathology is a feature of both diseases. A question arises regarding the contribution of LC degeneration to the occurrence of poor QoS.
    UNASSIGNED: To evaluate the association between LC impairment and sleep disorders in ET and PD patients.
    UNASSIGNED: A total of 83 patients with ET, 124 with PD, and 83 healthy individuals were recruited and divided into ET/PD with/without poor QoS (Sle/NorET and Sle/NorPD) subgroups according to individual Pittsburgh Sleep Quality Index (PSQI) score. Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and free-water imaging derived from diffusion MRI were performed. Subsequently, we evaluated the association between contrast-to-noise ratio of LC (CNRLC) and free-water value of LC (FWLC) with PSQI scores in ET and PD groups.
    UNASSIGNED: CNRLC was significantly lower in ET (p = 0.047) and PD (p = 0.018) than in healthy individuals, whereas no significant difference was found in FWLC among the groups. No significant differences were observed in CNR/FWLC between patients with/without sleep disorders after multiple comparison correction. No correlation was identified between CNR/FWLC and PSQI in ET and PD patients.
    UNASSIGNED: LC degeneration was observed in both ET and PD patients, implicating its involvement in the pathophysiology of both diseases. Additionally, no significant association was observed between LC integrity and PSQI, suggesting that LC impairment might not directly relate to overall QoS.
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  • 文章类型: Journal Article
    是否,到什么程度,以及中枢神经系统(CNS)中的轴突如何承受突然的机械冲击尚不清楚。通过使用微流体装置对轴突施加受控的横向机械应力,我们确定了大多数轴突可以承受的压力水平,并以纳米级分辨率探索了它们的即时反应。我们发现轻度压力会触发一种高度可逆的,快速轴突成珠反应,由依赖肌动球蛋白-II的动态直径调制驱动。这种机制有助于阻碍应激诱导的Ca2升高向非应激神经元区域的远距离传播。通过体外药理和分子操作,我们发现肌动球蛋白II失活会减少可逆的成珠过程,促进进行性Ca2扩散,从而增加应力轴突的急性轴突变性。相反,上调肌动球蛋白-II活性可防止初始损伤的进展,在体外和体内保护应力轴突免受急性变性。我们的研究揭示了轴突皮层中的周期性肌动球蛋白II作为一种新颖的保护机制,保护神经元免受机械应力造成的有害影响。
    Whether, to what extent, and how the axons in the central nervous system (CNS) can withstand sudden mechanical impacts remain unclear. By using a microfluidic device to apply controlled transverse mechanical stress to axons, we determined the stress levels that most axons can withstand and explored their instant responses at nanoscale resolution. We found mild stress triggers a highly reversible, rapid axon beading response, driven by actomyosin-II-dependent dynamic diameter modulations. This mechanism contributes to hindering the long-range spread of stress-induced Ca2+ elevations into non-stressed neuronal regions. Through pharmacological and molecular manipulations in vitro, we found that actomyosin-II inactivation diminishes the reversible beading process, fostering progressive Ca2+ spreading and thereby increasing acute axonal degeneration in stressed axons. Conversely, upregulating actomyosin-II activity prevents the progression of initial injury, protecting stressed axons from acute degeneration both in vitro and in vivo. Our study unveils the periodic actomyosin-II in axon shafts cortex as a novel protective mechanism, shielding neurons from detrimental effects caused by mechanical stress.
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  • 文章类型: Journal Article
    背景:作为死亡和长期残疾的主要原因,急性缺血性卒中可产生深远的病理生理后果。越来越多的证据表明,中风后下部运动系统出现异常,而对侧脊髓腹角(VH)神经元的跨突触变性仍存在争议。
    方法:使用急性缺血性中风大鼠模型,我们用免疫荧光染色分析了卒中后脊髓VH神经元的对侧和同侧计数。此外,我们通过同时测量改良的神经严重度评分(mNSS)来估计卒中后整体较低的运动单位异常,复合肌肉动作电位(CMAP)振幅,重复神经刺激(RNS),脊髓VH神经元计数,和相应的肌纤维形态。还评估了脊髓VH中小胶质细胞和细胞外信号调节激酶1/2(ERK1/2)的活化状态。
    结果:卒中后7天,对侧CMAP振幅下降到最低点,表明运动功能损伤较低,同侧观察到明显的肌肉废用萎缩;同时,VH神经元保持完整。局灶性中风后14天,较低的运动功能恢复与减轻肌肉废用萎缩,而跨突触变性发生在对侧,ERK1/2的激活升高,并发生神经源性肌肉萎缩。在整个实验过程中,RNS没有观察到CMAP振幅的明显减小。
    结论:本研究提供了实验性缺血大鼠下运动系统变化的概述。我们证明,当较低的运动功能显着恢复时,对侧VH神经元发生跨突触变性,这表明在局灶性缺血性中风的急性和亚急性阶段,跨突触变性在较低运动功能障碍中的次要作用。
    BACKGROUND: As a leading cause of mortality and long-term disability, acute ischemic stroke can produce far-reaching pathophysiological consequences. Accumulating evidence has demonstrated abnormalities in the lower motor system following stroke, while the existence of Transsynaptic degeneration of contralateral spinal cord ventral horn (VH) neurons is still debated.
    METHODS: Using a rat model of acute ischemic stroke, we analyzed spinal cord VH neuron counts contralaterally and ipsilaterally after stroke with immunofluorescence staining. Furthermore, we estimated the overall lower motor unit abnormalities after stroke by simultaneously measuring the modified neurological severity score (mNSS), compound muscle action potential (CMAP) amplitude, repetitive nerve stimulation (RNS), spinal cord VH neuron counts, and the corresponding muscle fiber morphology. The activation status of microglia and extracellular signal-regulated kinase 1/2 (ERK 1/2) in the spinal cord VH was also assessed.
    RESULTS: At 7 days after stroke, the contralateral CMAP amplitudes declined to a nadir indicating lower motor function damage, and significant muscle disuse atrophy was observed on the same side; meanwhile, the VH neurons remained intact. At 14 days after focal stroke, lower motor function recovered with alleviated muscle disuse atrophy, while transsynaptic degeneration occurred on the contralateral side with elevated activation of ERK 1/2, along with the occurrence of neurogenic muscle atrophy. No apparent decrement of CMAP amplitude was observed with RNS during the whole experimental process.
    CONCLUSIONS: This study offered an overview of changes in the lower motor system in experimental ischemic rats. We demonstrated that transsynaptic degeneration of contralateral VH neurons occurred when lower motor function significantly recovered, which indicated the minor role of transsynaptic degeneration in lower motor dysfunction during the acute and subacute phases of focal ischemic stroke.
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  • 文章类型: Journal Article
    探讨Fas-L对大鼠外周延伸损伤修复再生的调节作用。
    本研究利用损伤神经动物模型的相关实验技术,探讨Fas-L对大鼠周围神经修复再生过程中背根神经节(DRG)细胞凋亡和轴突再生的影响。细胞生物学,和分子生物学。
    坐骨神经损伤后DRG组织中Fas-L的表达水平显著下调。干扰Fas-L可显著促进DRG神经元轴突再生,抑制细胞凋亡,而Fas-L的过表达则相反。此外,Fas-L可能通过影响多个信号通路参与SD大鼠DRG功能的调节及周围神经的修复与再生,如p-AKT/AKT,β-连环蛋白,和NF-κB。
    Fas-L可能对SD大鼠周围神经损伤的修复和再生有一定的影响,为周围神经功能重建提供实验依据和新的理论依据。
    坐骨神经损伤后DRG组织中Fas-L的表达水平显著下调。Fas-L能显著促进DRG神经元轴突再生,抑制细胞凋亡。Fas-L可能通过影响多个信号通路参与SD大鼠DRG功能的调节及周围神经的修复与再生,如p-AKT/AKT,β-连环蛋白,和NF-κB。Fas-L可能对SD大鼠周围神经损伤的修复和再生有一定的影响,为周围神经功能重建提供实验依据和新的理论依据。
    UNASSIGNED: To investigate the regulatory effect of Fas-L on the repair and regeneration of peripheral extension injury in rats.
    UNASSIGNED: This study aimed to explore the effects of Fas-L on apoptosis and axonal regeneration of dorsal root ganglion (DRG) cells in rat peripheral nerve repair and regeneration by using several relevant experimental techniques from the injured nerve animal model, cell biology, and molecular biology.
    UNASSIGNED: The expression level of Fas-L in DRG tissues was significantly down-regulated after sciatic nerve injury. Interference with Fas-L can significantly promote the regeneration of DRG neuronal axons and inhibit apoptosis, while the overexpression of Fas-L is contrary to it. Moreover, Fas-L may play a role in the regulation of DRG function and the repair and regeneration of peripheral nerves in Sprague Dawley (SD) rats by affecting several signaling pathways, such as p-AKT/AKT, β-catenin, and NF-κB.
    UNASSIGNED: Fas-L may have a certain effect on the repair and regeneration of peripheral nerve injury in SD rats, which may provide an experimental basis and a new theoretical basis for the functional reconstruction of peripheral nerves.
    UNASSIGNED: The expression level of Fas-L in DRG tissues was significantly down-regulated after sciatic nerve injury. Fas-L can significantly promote the regeneration of DRG neuronal axons and inhibit apoptosis. Fas-L may play a role in the regulation of DRG function and the repair and regeneration of peripheral nerves in SD rats by affecting several signaling pathways, such as p-AKT/AKT, β-catenin, and NF-κB. Fas-L may have a certain effect on the repair and regeneration of peripheral nerve injury in SD rats, which may provide an experimental basis and a new theoretical basis for the functional reconstruction of peripheral nerves.
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  • 文章类型: Journal Article
    神经元丢失是阿尔茨海默病(AD)的中心问题,然而,迄今为止尚未开发出可以阻止AD相关神经变性的治疗方法。这里,我们开发了针对217位点磷酸化的人tau(p-tau217)的单克隆抗体(mAb2A7),并观察到p-tau217水平与AD患者的脑萎缩和认知障碍呈正相关.鼻内给药有效地将mAb2A7递送到雄性PS19tau病鼠脑中,具有靶接合和减少tau病理/聚集,而对总可溶性tau几乎没有影响。Further,mAb2A7治疗阻断了凋亡相关的神经元丢失和脑萎缩,逆转的认知缺陷,并改善雄性牛磺酸病鼠的运动功能。蛋白质组学分析显示,mAb2A7治疗逆转了主要与鼠tau蛋白病和AD脑中观察到的突触功能相关的蛋白质的改变。靶向总tau的抗体(13G4)也减弱了tau相关的病理学和神经变性,但损害了雄性tau病鼠的运动功能。这些结果暗示p-tau217是AD相关神经变性的潜在治疗靶标。
    Neuronal loss is the central issue in Alzheimer\'s disease (AD), yet no treatment developed so far can halt AD-associated neurodegeneration. Here, we developed a monoclonal antibody (mAb2A7) against 217 site-phosphorylated human tau (p-tau217) and observed that p-tau217 levels positively correlated with brain atrophy and cognitive impairment in AD patients. Intranasal administration efficiently delivered mAb2A7 into male PS19 tauopathic mouse brain with target engagement and reduced tau pathology/aggregation with little effect on total soluble tau. Further, mAb2A7 treatment blocked apoptosis-associated neuronal loss and brain atrophy, reversed cognitive deficits, and improved motor function in male tauopathic mice. Proteomic analysis revealed that mAb2A7 treatment reversed alterations mainly in proteins associated with synaptic functions observed in murine tauopathy and AD brain. An antibody (13G4) targeting total tau also attenuated tau-associated pathology and neurodegeneration but impaired the motor function of male tauopathic mice. These results implicate p-tau217 as a potential therapeutic target for AD-associated neurodegeneration.
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  • 文章类型: Journal Article
    嗜神经病毒感染可能导致宿主行为的变化,这与神经元的退行性变化密切相关。Lyssavirus属包括高度嗜神经病毒,包括狂犬病病毒(RABV),已经被证明可以诱导神经元的退行性变化,以轴突的自我毁灭为标志。RABV降解神经元细胞骨架蛋白的潜在机制仍然不完整。在这项研究中,我们表明,RABV感染或其M蛋白的过表达可以通过与Slc25a4结合来破坏线粒体代谢。这导致NAD产生减少,随后Ca2从内质网和线粒体流入神经元细胞系的细胞质,激活Ca2依赖性蛋白酶钙蛋白酶,降解α-微管蛋白。我们进一步筛选了不同病毒的M蛋白,发现狗来源的RABV株(DRV)的M蛋白不会降解α-微管蛋白。DRVM蛋白和实验室减毒的RABV菌株CVS的序列分析表明,第57个氨基酸对于M诱导的微管降解至关重要。我们产生了重组RABV,其M蛋白的第57个氨基酸位置具有突变,并表明该突变可减少体外α-微管蛋白降解和体内轴突变性。本研究阐明了裂解病毒诱导神经元变性的机制。重要以前的研究表明,RABV(狂犬病病毒,lyssavirus的代表)感染诱导神经元结构异常。但是,很少有文章介绍了Lysavirus对神经元的作用机制,RABV感染如何诱导神经功能障碍的机制仍不完全。Lyssavirus的M蛋白可以通过与Slc25a4相互作用来下调细胞ATP水平,这种ATP的减少导致细胞质中NAD+水平的降低,这导致从细胞内钙库释放Ca2+,内质网,和线粒体.细胞质中大量Ca2的存在激活了Ca2依赖性蛋白酶并降解了微管蛋白。M蛋白的氨基酸57是决定其破坏线粒体代谢和随后的神经元变性的关键位点。
    Infection with neurotropic viruses may result in changes in host behavior, which are closely associated with degenerative changes in neurons. The lyssavirus genus comprises highly neurotropic viruses, including the rabies virus (RABV), which has been shown to induce degenerative changes in neurons, marked by the self-destruction of axons. The underlying mechanism by which the RABV degrades neuronal cytoskeletal proteins remains incomplete. In this study, we show that infection with RABV or overexpression of its M protein can disrupt mitochondrial metabolism by binding to Slc25a4. This leads to a reduction in NAD+ production and a subsequent influx of Ca2+ from the endoplasmic reticulum and mitochondria into the cytoplasm of neuronal cell lines, activating Ca2+-dependent proteinase calpains that degrade α-tubulin. We further screened the M proteins of different lyssaviruses and discovered that the M protein of the dog-derived RABV strain (DRV) does not degrade α-tubulin. Sequence analysis of the DRV M protein and that of the lab-attenuated RABV strain CVS revealed that the 57th amino acid is vital for M-induced microtubule degradation. We generated a recombinant RABV with a mutation at the 57th amino acid position in its M protein and showed that this mutation reduces α-tubulin degradation in vitro and axonal degeneration in vivo. This study elucidates the mechanism by which lyssavirus induces neuron degeneration.IMPORTANCEPrevious studies have suggested that RABV (rabies virus, the representative of lyssavirus) infection induces structural abnormalities in neurons. But there are few articles on the mechanism of lyssavirus\' effect on neurons, and the mechanism of how RABV infection induces neurological dysfunction remains incomplete. The M protein of lyssavirus can downregulate cellular ATP levels by interacting with Slc25a4, and this decrease in ATP leads to a decrease in the level of NAD+ in the cytosol, which results in the release of Ca2+ from the intracellular calcium pool, the endoplasmic reticulum, and mitochondria. The presence of large amounts of Ca2+ in the cytoplasm activates Ca2+-dependent proteases and degrades microtubule proteins. The amino acid 57 of M protein is the key site determining its disruption of mitochondrial metabolism and subsequent neuron degeneration.
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  • 文章类型: Journal Article
    GJB2基因突变是常染色体隐性遗传非综合征性遗传性耳聋的最常见原因。对于患有严重至深度GJB2相关耳聋的个体,人工耳蜗已成为改善听觉的唯一补救措施。先前的一些研究强调了保留耳蜗神经成分在耳蜗植入后获得良好结果的关键作用。因此,我们建立了一个条件敲除小鼠模型(Cx26-CKO),其中Cx26在Sox2启动子驱动的耳蜗支持细胞中完全缺失。Cx26-CKO小鼠表现出严重的听力损失和毛细胞和Deiter细胞的大量损失,这代表了由GJB2基因突变引起的人类耳聋的极端形式。此外,发现了周围听觉神经系统的多种病理变化,包括异常神经支配,脱髓鞘,Cx26-CKO小鼠中螺旋神经节神经元的变性以及heminodes的破坏。这些发现为Cx26-null小鼠的耳聋机制和严重耳聋的治疗提供了宝贵的见解。
    GJB2 gene mutations are the most common causes of autosomal recessive non-syndromic hereditary deafness. For individuals suffering from severe to profound GJB2-related deafness, cochlear implants have emerged as the sole remedy for auditory improvement. Some previous studies have highlighted the crucial role of preserving cochlear neural components in achieving favorable outcomes after cochlear implantation. Thus, we generated a conditional knockout mouse model (Cx26-CKO) in which Cx26 was completely deleted in the cochlear supporting cells driven by the Sox2 promoter. The Cx26-CKO mice showed severe hearing loss and massive loss of hair cells and Deiter\'s cells, which represented the extreme form of human deafness caused by GJB2 gene mutations. In addition, multiple pathological changes in the peripheral auditory nervous system were found, including abnormal innervation, demyelination, and degeneration of spiral ganglion neurons as well as disruption of heminodes in Cx26-CKO mice. These findings provide invaluable insights into the deafness mechanism and the treatment for severe deafness in Cx26-null mice.
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