Neuromyelitis spectrum disease (NMOSD) is an immune-mediated inflammatory demyelinating disease of the central nervous system. The breakdown of the blood-brain barrier (BBB), as an important link in the pathogenesis of NMOSD, has an important impact on the occurrence, development and prognosis of the disease. It is generally believed that the aquaporin 4 antibody produced in the peripheral circulation crosses the BBB cause damage to the central nervous system, and there are components involved in the destruction of BBB in the occurrence and development of NMOSD disease. At present, little is known about the molecular mechanism of BBB destruction in NMOSD lesions and there is still a lack of systematic theory. Further research and exploration of the regulatory mechanism of BBB permeability and the manifestation of barrier destruction in NMOSD diseases are of great significance for understanding the pathogenesis of NMOSD, so as to achieve early diagnosis and discover new therapeutic and preventive targets.
Objective:To observe the effects of testosterone on optic nerve an d retinal ganglion cells (RGC) in experimental autoimmune encephalomyelitis (EAE ). Methods:Fourty one female Wistar rats were randomly divide d into 3 groups: the normal group (10 rats), the untreated control group (15 rats) and the testos terone group (16 rats). The rats in the first two groups were fed with 1% ethano l every day, and the rats in the testosterone group were fed with methyltestoste rone (0.25 mg/kg) every day. On the 20th day, EAE model was induced in the untre ated control group and the testosterone group by injecting guinea pig spinal cor d homogenate in complete Freund's adjuvant and bordetella pertussis vaccine. RGC were labeled with flurogold (FG) by injecting it in superior colliculus and lat eral geniculate body 7 days before establishing EAE model. All rats were fed wit h drugs continuously, and after 1430 days, rats in normal group and rats in un t reated control and testosterone groups who had symptoms within 48~72 hours were observed by light microscopy and flash visual evoked potential (FVEP) to detect the functional and morphological changes of optic nerve. The number of RGC was counted by fluorescence microscopy,and apoptosis of RGC was observed by termina l deoxynucleotidyl transferasemediated biotinylated UTP nick end labeling (TUN E L) Results:EAE rats presented weakness or paralysis of tail a nd hind limbs 10 days after establishing EAE model. Compared with the rats in the untreated contr ol group, the rats in the testosterone group had longer disease delitescence and lower clinical score (P=0.042). Extensive demyelination of optic nerves wi th the circuitous configuration was found in the untreated control group; while mild demyelination of optic nerves with regular figure was found in the testosterone group. In the testosterone group, the latency of N1、P and N2 wave was shorter w hile the amplitude ofN1-P and P-N2was higher than that in the untreated cont rol group (Plt;0.05). The number of RGC was (2284plusmn;132), (934plusmn;78, and (1725 plusmn;95)cells/mm2 in the normal, untreated control and testosterone groups, respectively; w hich was higher in testosterone group than that in untreated control group (P=0.028). The number of TUNEL positive cells was (4.02plusmn;0.16), (24.44plusmn;2.22), and (9.84plusmn;2.36) cells per high power field (times;400) in the 3 grou ps, respectively; wh ich was less in testosterone group than that in untreated control group (P=0.025). Conclusions:Testosterone may reduce the incidence and clinical score of EAE, inhibit the apoptosis of RGC, alleviate the demyelinatio n of optic nerves, and improved the conduction function of optic nerves.
【摘要】 目的 在實驗性自身免疫性腦脊髓炎(experimental autoimmune encephalomyelitis,EAE)模型中,比較常規T2加權成像(T2weighted imaging,T2WI)、釓二乙三胺五醋酸(gadoliniumdiethylenetriamine pentaacetic acid,GdDTPA)和超順磁性氧化鐵(superparamagnetic iron oxide,SPIO)增強圖像之間的差異,探討巨噬細胞在多發性硬化(multiple sclerosis,MS)炎性活動病灶中的細胞學標志。方法 在EAE模型臨床癥狀的亞臨床期、初發期、高峰期,13只復發緩解(relapsingremitting,RR)EAE大鼠模型組和13只正常對照組大鼠在注入對比劑之前均行常規T2WI掃描,接著分別在其尾靜脈注入GdDTPA后5 min行T1加權成像(T1weighted imaging,T1WI),再注入SPIO,24 h后行T2WI掃描。掃描完畢后立即處死大鼠取腦,行腦組織切片的ED1免疫組織化學染色和Prussian blue染色。結果 EAE模型組大鼠在第11天出現臨床癥狀(初發期),第14天達到高峰期;MRI檢查:SPIO增強圖像對EAE病灶的顯示較常規T2WI和GdDTPA增強圖像好。病理學檢查:ED1染色,在SPIO顯示為低信號的區域內出現了炎癥細胞(以巨噬細胞為主)浸潤;Prussian blue染色示病灶內巨噬細胞胞質內出現了藍染顆粒,沉積部位與T2WI上低信號區對應。對照組大鼠均無異常。結論 SPIO較GdDTPA更好地顯示EAE模型中炎性活動性病灶內血管周圍以巨噬細胞為主的浸潤。
Neuromyelitis optica-related optic neuritis (NMO-ON) is a kind of severe optic nerve disease, which always leads to replase, poor prognosis, and even blindness. Aquaporin 4 antibody (AQP4-IgG) is the main diagnostic biomarker for neuromyelitis optica with high specificity. Serum myelin oligodendrocyte glycoprotein antibody (MOG-IgG) is helpful for the diagnosis of AQP4-IgG negative patients. The study of biomarkers is helpful to deeply understand the pathogenesis of NMO-ON, help the diagnosis of the disease, and finally make precise treatment. Orbital MRI can help to differentiate MOG-IgG positive from AQP4-IgG positive neuromyelitis optica and optic neuritis, which is very important for the diagnosis of NMO-ON. At present, the standardized treatment of NMO-ON can be divided into two clinical stages: acute stage and remission stage. Corticosteroids and plasma exchange are the main treatments in acute stage, aiming at alleviating acute inflammatory reaction and improving prognosis. Immunosuppressive agents and biological agents are the main treatments in remission stage, aiming at preventing or reducing recurrence. With the development of the diagnosis and treatment of NMO-ON, we find that it is more and more important to strengthen the construction of neuro-ophthalmology team in China, establish clinical epidemiological database of NMO-ON, and carry out multi-centre, large-sample, prospective clinical control studies in China to provide evidence-based medicine for Chinese people. In addition, we need to strengthen efforts to establish and improve the diagnostic criteria for NMO-ON and the promotion of diagnostic and therapeutic criteria, and strive to improve the clinical diagnosis and treatment level of NMO-ON in China.
ObjectiveTo study the relationship between brain white matter fiber occult lesions and P100 wave latency of visual evoked potential (VEP) in neuromyelitis optica (NMO) patients by diffusion tensor imaging (DTI). MethodsTwenty patients with NMO who were treated between July 2008 and April 2009 were selected as the trial group. According to the VEP test, the latency of P100 wave was prolonged, the NMO patients were divided into VEP abnormal group (trial group 1) and VEP normal group (trial group 2). Twenty healthy adult volunteers served as the control group. The DTI examination in brain was done to measure the fractional anisotropy (FA) value of optic nerve (FAn), optic tract (FAt), and optic radiation (FAr);and the mean diffusivity (MD) value of optic nerve (MDn), optic tract (MDt), and optic radiation (MDr). The FA, MD, and P100 wave latency were compared between groups, and the correlation between MD, FA, and P100 wave latency of NMO were analyzed. ResultsIn the 20 NMO patients, 13 patients with VEP had prolonged bilateral P100 wave latency prolongation or no wave (trial group 1), and 7 patients had normal bilateral P100 wave latency (trial group 2). Compared with the trial group 2 and the control group, the FA values were significantly decreased, and the MD values were significantly increased in the trial group 1 (P<0.05). There was no significant difference in the FA and MD values between the trial group 2 and the control group (P>0.05). All FA (FAn, FAt, and FAr) values of each part of NMO patients were negatively correlated with the latency of P100 wave (P<0.05), all MD (MDn, MDt, and MDr) values were positively correlated with the latency of P100 wave (P<0.05). ConclusionDTI could show small pathylogical changes in the white matter fibers of visual pathway, and there is a correlation between DTI and VEP in NMO, suggesting that a more comprehensive assessment to the condition and prognosis can be made through the VEP in the clinical indicators.
Neuromyelitis optica (NMO) is a kind of demyelinating disorder that preferentially affects the optic nerves and spinal cord and results in permanent vision loss. NMO pathogenesis is thought to involve binding of anti-aquaporin-4 (AQP4) auto-antibodies to astrocytes, which causes complement-dependent cytotoxicity (CDC) and downstream inflammation leading to oligodendrocyte and neuronal injury. Vasculocentric deposition of activated complement is a prominent feature of NMO pathology. In recent years, a number of groups have found complements play an important role in the pathogenesis of NMO, and basic researches in NMO therapy due to its specificity and uniformity. Its inhibition would protect against proteins in the classical complement pathway so that cure the disease. This review will expound the the role of complement signaling pathway in the pathogenesis of NMO, and provide reference for a more in-depth understanding and clinical treatments of NMO.