Objective Aminoguanidine (AG) can reduce brain edema and increase the recovery of neuron functions in surgical brain injury and stroke. To investigate the effect of AG on spinal cord injury (SCI) in rats and its mechanism. Methods A total of 150 adult male Sprague Dawley rats (weighing, 230-255 g) were divided into control group (group A, 25 rats without treatment), the sham-operated group (group B, 25 rats undergoing laminectomy), SCI group (group C, 25 SCI rats with injection of 5%DMSO), SCI + AG groups (groups D, E, and F, 25 SCI rats and AG injection of 75, 150, and 300 mg/kg, respectively). The optimal dosage of AG was screened by dry-wet weight method with the percentage of water content at 0, 12, 24, and 48 hours after injury. The blood-spinal cord barriar permeability was further detected by Evans blue (EB) method, aquaporins 4 (AQP4) mRNA expression by RT-PCR, AQP4 protein expression by immunohistochemistry and Western blot. Results AG injection at dosage of 150 mg/kg can significantly reduce edema of spinal cords at 12, 24, and 48 hours after SCI (P lt; 0.05), so 150 mg/kg was the optimal dosage. The EB content in group E was significantly lower than that in group C at 12, 24, and 48 hours after SCI, and the permeability of blood-spinal cord barrier was significantly decreased compared with group C (P lt; 0.05). The AQP4 mRNA expressions in groups B and E were significantly lower than that in group C at 12, 24, and 48 hours after SCI (P lt; 0.05). AQP4 protein expressions in groups B and E were significantly lower than that in group C at 24 and 48 hours after SCI (P lt; 0.05) by Western blot. Immunohistochemical staining revealed that AQP4 protein expression in group C was significantly higher than that in groups B and E (P lt; 0.05) at 48 hours after SCI, but no significant difference was found between group B and group E (P gt; 0.05). Conclusion AG injection at dosage of 150 mg/kg can induce spinal cord edema and injury in rats, which could be correlated with the down-regulation of AQP4 expression.
目的 探讨水通道蛋白4（AQP4）在脑胶质瘤性脑水肿的分子调节机制及与血管内皮生长因子（VEGF）的关系。 方法 收集2007年10月-2008年6月间65例脑胶质瘤患者手术切除新鲜肿瘤标本（胶质瘤Ⅰ级6例、Ⅱ级18例、Ⅲ级11例、Ⅳ级30例）。应用免疫荧光细胞化学方法检测肿瘤组织中AQP4蛋白和VEGF蛋白的阳性表达情况，并分析AQP4和VEGF的表达差异与关系。 结果 免疫荧光细胞化学法染色显示，AQP4蛋白在正常脑组织中主要表达于细胞膜表面，胞浆和细胞核着色较浅。在胶质瘤细胞内，AQP4广泛分布于胞浆内；肿瘤中AQP4表达和VEGF呈正相关（r=0.877，P=0.000）。 结论 在胶质瘤性脑水肿中，AQP4在胶质瘤细胞内主要分布于胞浆内，且与VEGF呈明显正相关。
ObjectiveTo observe the thickness of per-papillary retinal fiber layer (pRNFL) and structural changes of inner macular segmented layers in optic neuritis (ON) patients with positive aquaporin-4 antibody[AQP4-Ab(+)]. Methods60 ON patients (84 eyes) including 30 of AQP4-Ab(+) ON patients (42 eyes) and AQP4-Ab(-) ON patients (42 eyes), and 40 age-gender matched health controls(80 eyes) were recruited in present study. There was no statistical significance in gender (χ2=0.568) and age (χ2=1.472) between the three groups (P > 0.05). There was no statistical significance in the percentage of different course (χ2=0.000) and logMAR best corrected visual acuity (Z=-1.492) between AQP4-Ab(+)ON and AQP4-Ab(-)ON group (P=1.000, 0.136). All subjects were examined by Spectralis-OCT. The thickness of per-papillary, nasal, nasal lower, temporal lower, temporal, temporal upper, nasal upper and papillomacular bundle (PMB) were analyzed as well as nasal pRNFL/temporal pRNFL (N/T). The macular area was divided into three concentric circles which including central region with 1 mm diameter, inner area with > 1 mm but≤3 mm diameter, and outer ring area with > 3 mm but≤6 mm diameter. The macular volume in each partition and volume in macular RNFL (mRNFL), macular ganglion cell layer (mRGCL), macular inner plexiform layer (mIPL) and macular inner nuclear layer (mINL) were analyzed. ResultsCompared to HC group, the thickness of pRNFL, every quadrants and PMB were decreased significantly in ON group (P=0.000); the macular volume and the volume of mRNFL, mRGCL, mIPL were also decreased significantly in ON group (P=0.000); but there was no statistical difference in mINL volume between two groups (P=0.700). Compared to AQP4-Ab(-)ON group, the thickness of nasal and nasal lower were decreased significantly in AQP4-Ab(+)ON group (P=0.010, 0.000); the macular and mIPL volume were also decreased significantly in AQP4-Ab(+)ON group (P=0.038, 0.033); the thickness of inferior, superior and inferior mIPL in outer ring area and nasal mRNFL in inner area were decreased significantly in AQP4-Ab(+)ON group (P < 0.05). ConclusionsCompared to AQP4-Ab(-)ON patients, the pRNFL thickness and mIPL volume decreased in AQP4-Ab(+)ON patients. The thinner pRNFL area is mainly located in nasal, nasal lower quadrants, and inferior, superior mIPL.
ObjectiveTo investigate the changes in the nerve fiber layer of the cornea in patients with demyelinating optic neuritis (DON) and its correlation with visual acuity. MethodsA cross-sectional study. From March 2021 to July 2022, 27 cases (39 eyes) of DON patients diagnosed in the Department of Neurology and Ophthalmology of Beijing Tongren Hospital Affiliated to Capital Medical University were enrolled in this study. According to the serological test results, the patients were divided into aquaporin 4 antibody associated optic neuritis (AQP4-ON group) and myelin oligodendrocyte glycoprotein antibody associated optic neuritis (MOG-ON group), with 15 cases (19 eyes) and 12 cases (20 eyes) respectively. According to previous history of glucocorticoid treatment, the patients were divided into glucocorticoid treated group and non-glucocorticoid treated group, with 17 cases (27 eyes) and 10 cases (12 eyes) respectively. Twenty healthy volunteers (20 eyes) with age- and gender-matched were selected as the control group. All eyes underwent best corrected visual acuity (BCVA) and in vivo confocal microscopy (IVCM) examinations. BCVA was performed using Snellen's standard logarithmic visual acuity chart, which was converted into logarithmic minimum angle resolution (logMAR) visual acuity during statistics. The corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve fiber branch length (CNBL), corneal nerve fiber branch density (CNBD) and the density of corneal dendritic cells (DC) were detected by IVCM examination. Parameter comparison between groups by t-test and Kruskal-Wallis rank sum test. The correlation between logMAR BCVA and pamameters of corneal nerve fibers were analyzed using Spearman analysis. ResultsThe CNFL, CNFD, and CNBL of the DON group and the control group were (10.67±2.55) mm/mm2, (57.78±12.35) root/mm2, (3.27±1.34) mm/mm2, and (13.74±3.05) mm/mm2, (70.95±13.14) root/mm2, and (4.22±1.03) mm/mm2, respectively; the difference in CNFL, CNFD, and CNBL between the two groups were statistically significant (t=4.089, 3.795, 2.773; P＜0.05). The CNFL, CNBL, and CNBD of the affected eyes in the MOG-ON group and AQP4-ON group were (12.02±2.13) mm/mm2, (3.80±1.19) mm/mm2, (47.97±8.86) fibers/mm2, and (9.25±2.19) mm/mm2, (2.72±1.19) mm/mm2, (39.43±13.86) fibers/mm2, respectively; the differences in CNFL, CNBL, and CNBD between the two groups were statistically significant (t=－4.002, －2.706, －2.306; P＜0.05). The corneal DC density of the patients in the hormone treated group and the non-hormone treated group was (24.43±8.32) and (41.22±9.86) cells/mm2, respectively. The difference in corneal DC density between the two subgroups was statistically significant (P＜0.001). Correlation analysis showed that there was a significant negative correlation between logMAR BCVA and CNBL and CNFL in patients with DON (r=－0.422, －0.456; P＜0.05). ConclusionsThere are different degrees of corneal nerve fiber damage in patients with different types of DON. There was a negative correlation between BCVA and the length of corneal nerve fibers.
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.