脱髓鞘疾病51例

目的分析小儿脱髓鞘疾病的临床特点,以提高对该疾病的诊断与治疗。方法对51例小儿脱髓鞘疾病的发病年龄、前驱症状、临床表现及辅助检查特点等进行回顾性分析。结果51例脱髓鞘疾病患儿中学龄期38例,有前驱感染史32例,疫苗接种史3例,大多以急性起病。周围神经脱髓鞘疾病32例以双下肢或四肢瘫痪为首发;中枢神经脱髓鞘疾病以视力障碍、肢体无力、发热、抽搐、头痛等为首发。周围神经脱髓鞘疾病患儿中15例行肌电图检查,均显示为神经源性改变;18例中枢神经脱髓鞘疾病患儿中17例行CT或MRI,均发现异常信号。结论小儿脱髓鞘疾病的临床表现复杂多变,通过病史及辅助检查,进行综合分析,不难得出诊断,预后良好。     

The pathological diagnosis of nerve biopsies: a practical approach

The approach to the neuropathological assessment of nerve biopsies is the main focus of this review. Nerve biopsies are invasive diagnostic procedures resulting in a permanent neurological deficit, and are therefore carried out only following an in-depth clinical assessment including laboratory, imaging, electrophysiological, and where appropriate also genetic studies. This review will outline the key diagnostic approaches and will discuss neuropathies relevant in clinical practice, caused by vasculitis, inflammatory demyelination, dysproteinaemic, amyloid, toxic agents, and neuropathies due to genetic conditions.     

Diffusion tensor imaging detects treatment effects of FTY720 in experimental autoimmune encephalomyelitis mice

Fingolimod (FTY720) is an orally available sphingosine‐1‐phosphate (S1P) receptor modulator reducing relapse frequency in patients with relapsing–remitting multiple sclerosis (RRMS). In addition to immunosuppression, neuronal protection by FTY720 has also been suggested, but remains controversial. Axial and radial diffusivities derived from in vivo diffusion tensor imaging (DTI) were employed as noninvasive biomarkers of axonal injury and demyelination to assess axonal protection by FTY720 in experimental autoimmune encephalomyelitis (EAE) mice. EAE was induced through active immunization of C57BL/6 mice using myelin oligodendrocyte glycoprotein peptide 35–55 (MOG_35–55). We evaluated both the prophylactic and therapeutic treatment effect of FTY720 at doses of 3 and 10 mg/kg on EAE mice by daily clinical scoring and end‐point in vivo DTI. Prophylactic administration of FTY720 suppressed the disease onset and prevented axon and myelin damage when compared with EAE mice without treatment. Therapeutic treatment by FTY720 did not prevent EAE onset, but reduced disease severity, improving axial and radial diffusivity towards the control values without statistical significance. Consistent with previous findings, in vivo DTI‐derived axial and radial diffusivity correlated with clinical scores in EAE mice. The results support the use of in vivo DTI as an effective outcome measure for preclinical drug development. Copyright © 2013 John Wiley & Sons, Ltd.     

Nlrp3敲减对cuprizone诱导的脱髓鞘小鼠焦虑症状的影响

目的:探讨NOD样受体家族pyrin域3(Nod like receptor family pyrin domain containing 3,Nlrp3)对脱髓鞘损伤致小鼠焦虑情绪的影响。方法:雄性C57BL/6小鼠分为对照组、双环己酮草酰二腙(CPZ)模型组、CPZ+Nlrp3 shiNA组和Nlrp3 shRNA组;将对照或Nlrp3 shRNA慢病毒分别立体定位注射至小鼠胼胝体。1周后,小鼠喂食CPZ并测量喂食期间小鼠体质量;开场实验检测小鼠活动区域与距离,LFB-PAS染色观察脱髓鞘程度。结果:CPZ喂食2周内,小鼠平均体质量急剧下降;到5周时,CPZ模型组平均体质量显著低于对照组与CPZ+Nlrp3 shRNA组。行为学检测显示,对照组和CPZ+Nlrp3 shRNA组小鼠后肢站立次数较CPZ模型组明显减少,而中央区域活动距离与活动总距离的比值CPZ模型组显著增加。LFBPAS染色显示CPZ模型组胼胝体膝部髓鞘几乎完全缺失,其髓鞘化评分显著低于正常和CPZ+Nlpr3shRNA组。结论:Nlrp3敲减可缓解CPZ诱导的小鼠髓鞘脱失,并改善其焦虑症状。     

Cuprizone‐induced demyelination and demyelination‐associated inflammation result in different proton magnetic resonance metabolite spectra

Conventional MRI is frequently used during the diagnosis of multiple sclerosis but provides only little additional pathological information. Proton MRS (¹H‐MRS), however, provides biochemical information on the lesion pathology by visualization of a spectrum of metabolites. In this study we aimed to better understand the changes in metabolite concentrations following demyelination of the white matter. Therefore, we used the cuprizone model, a well‐established mouse model to mimic type III human multiple sclerosis demyelinating lesions. First, we identified CX₃CL1/CX₃CR1 signaling as a major regulator of microglial activity in the cuprizone mouse model. Compared with control groups (heterozygous CX₃CR1^+/? C57BL/6 mice and wild type CX₃CR1^+/+ C57BL/6 mice), microgliosis, astrogliosis, oligodendrocyte cell death and demyelination were shown to be highly reduced or absent in CX₃CR1^?/? C57BL/6 mice. Second, we show that ¹H‐MRS metabolite spectra are different when comparing cuprizone‐treated CX₃CR1^?/? mice showing mild demyelination with cuprizone‐treated CX₃CR1^+/+ mice showing severe demyelination and demyelination‐associated inflammation. Following cuprizone treatment, CX₃CR1^+/+ mice show a decrease in the Glu, tCho and tNAA concentrations as well as an increased Tau concentration. In contrast, following cuprizone treatment CX₃CR1^?/? mice only showed a decrease in tCho and tNAA concentrations. Therefore, ¹H‐MRS might possibly allow us to discriminate demyelination from demyelination‐associated inflammation via changes in Tau and Glu concentration. In addition, the observed decrease in tCho concentration in cuprizone‐induced demyelinating lesions should be further explored as a possible diagnostic tool for the early identification of human MS type III lesions. Copyright © 2015 John Wiley & Sons, Ltd.     

Attenuation of Corpus Callosum Axon Myelination and Remyelination in the Absence of Circulating Sex Hormones

Sex differences in the structure and organization of the corpus callosum (CC) can be attributed to genetic, hormonal or environmental effects, or a combination of these factors. To address the role of gonadal hormones on axon myelination, functional axon conduction and immunohistochemistry analysis of the CC in intact, gonadectomized and hormone‐replaced gonadectomized animals were used. These groups were subjected to cuprizone diet‐induced demyelination followed by remyelination. The myelinated component of callosal compound action potential was significantly decreased in ovariectomized and castrated animals under normal myelinating condition. Compared to gonadally intact cohorts, both gonadectomized groups displayed more severe demyelination and inhibited remyelination. Castration in males was more deleterious than ovariectomy in females. Callosal conduction in estradiol‐supplemented ovariectomized females was significantly increased during normal myelination, less attenuated during demyelination, and increased beyond placebo‐treated ovariectomized or intact female levels during remyelination. In castrated males, the non‐aromatizing steroid dihydrotestosterone was less efficient than testosterone and estradiol in restoring normal myelination/axon conduction and remyelination to levels of intact males. Furthermore, in both sexes, estradiol supplementation in gonadectomized groups increased the number of oligodendrocytes. These studies suggest an essential role of estradiol to promote efficient CC myelination and axon conduction in both sexes.     

大麻素对双环己酮草酰二腙诱导的脱髓鞘模型小鼠髓鞘的修复作用

目的：探讨大麻素（WIN55212-2）对双环己酮草酰二腙（cuprizone）诱导的脱髓鞘模型小鼠髓鞘的修复作用,阐明其可能机制。方法：选取C57BL/6小鼠95只,随机分为空白对照组、模型组（0.2%的cuprizone饲料喂养6周）、二甲基亚砜（DMSO）组（0.2% cuprizone饲料喂养3周后开始腹腔注射等量的DMSO混合液）和治疗组（0.2% cuprizone饲料喂养3周后开始腹腔注射1 mg·kg^-1 WIN55212-2）。采用黑金Ⅱ髓鞘染色技术对小鼠髓鞘组织染色,观察其组织形态表现;采用Western blotting法检测小鼠大脑组织中结侧蛋白（JN）、髓鞘碱性蛋白（MBP）和转录因子Nkx2.2蛋白表达水平。结果：黑金Ⅱ髓鞘染色,空白对照组小鼠大脑胼胝体区域有明显的着色,模型组小鼠大脑胼胝体区着色较浅。与空白对照组比较,模型组小鼠大脑组织中JN和MBP蛋白表达水平均明显降低（P<0.05）;与模型组和DMSO组比较,治疗组小鼠大脑组织中JN和Nkx2.2蛋白表达水平明显升高（P<0.05或P<0.01）。结论：大麻素可能通过转录因子Nkx2.2蛋白促进cuprizone诱导的脱髓鞘模型小鼠大脑组织中JN蛋白表达,促进髓鞘再生和修复。     

The role of complement in neurological and neuropsychiatric diseases

The complement system is a major component of innate immunity and a potent driver of inflammation. It has key roles in host defense against pathogens but can also contribute to pathology by driving inflammation and cell damage in diverse diseases. Complement has emerged as an important factor in the pathogenesis of numerous diseases of the CNS and PNS, including infectious, autoimmune and degenerative disorders, and is increasingly implicated in neuropsychiatric disease. Establishing the roles and relevance of complement in disease pathogenesis has become ever more important in recent years as new drugs targeting the complement system have reached the clinic, and the potential for using complement analytes as disease biomarkers has been recognized. In this brief review, the author summarizes the evidence implicating complement in these diseases and outlines ways in which this new understanding can be used to aid diagnosis and improve outcome.