Objective To investigate the effect of chondroitinase ABC (ChABC) on the expression of growth associated protein 43 (GAP-43) and gl ial fibrillary acidic protein (GFAP) after spinal cord injury (SCI) in rats. Methods A total of 150 adult female SD rats, weighing 250-300 g, were randomly divided into ChABC treatment group (group A), sal ine treatment group (group B), and sham operation group (group C) with 50 rats in each group. In groups A and B, the rats were made the SCI models and were treated by subarachnoid injection of ChABC and sal ine; in group C, the rats were not treated as a control. At 1, 3, 7, 14, and 21 days after operation, the Basso, Beattie, and Bresnahan (BBB) score system was used toevaluate the motion function, and immunofluorescent histochemical staining was used to observe the expressions of GAP-43 and GFAP. Results At different time points, the BBB scores of groups A and B were significantly lower than those of group C (P lt; 0.05); there was no significant difference in BBB score between groups A and B after 1, 3, and 7 days of operation (P gt; 0.05), but the BBB score of group A was significantly higher than that of group B after 14 and 21 days of operation (P lt; 0.01). At different time points, the GAP-43 and GFAP positive neurons of groups A and B were significantly higher than those of group C (P lt; 0.05). After 14 and 21 days of operation, the GAP-43 positive neurons of group A were more than those of group B (P lt; 0.01). After 7, 14, and 21 days of operation, the GFAP positive neurons of group A were significantly less than those of group B (P lt; 0.01). Conclusion ChABC can degrade gl ial scar, improve the microenvironment of the injured region and enhance the expression of GAP-43, which promotes axonal growth and extension.
Objective To observe the different effect such as high concentration of glucose and high concentration of insulin on GLUT1 of Rabbit Retinal Muuml;ller Cell in vitro. Methods Rabbit retinal Muuml;ller cells were cultured in vitro with suspended constitution，which were divided as the following groups: common control group，high glucose group，insulin group，high glucose combined insulin group. Laser confocal microscope combined with immunocytochemical and fluorescence staining method to quantitatively analyze the expression condition of GLUT1. Results The expression of GLUT1 has been enhanced obviously by high glucose and high insulin，which locates mainly in the cytoplasm that near to the nucleus. Conclusion Rabbit retinal Muuml;ller cells can express GLUT1，and the expression of GLUT1 can be reinforced by high glucose and high insulin. （Chin J Ocul Fundus Dis，2008，24：265-267）
Objective To observe the dynamic expression of nestin and glial fibrilary acidic protein (GFAP) in the development of retina in rats.Methods In 48 Wistar rats, 24 were divided into 8 groups with 3 rats in each according to their age (1 day, 1 week, and 2, 3, 4, 7, 12, and 20 weeks old). The sagittal freezing sections of the eye were made; nestin/glutamine synthetase (GS) and GFAP/GS were stained by immunofluorescence and were observed under the confocal microscope. Total RNA was extracted from 18 rats which were divided into 6 groups according to the age (1 day, 1 week, and 2, 3, 4, and 12 weeks old) with 3 rats in each. The expression of nestin, GAFA and GS mRNA were detected by realtime quantitative reverse transcription polymerase chain reaction (RT-PCR). Müller cells were cultured from postnatal day 7-12 rats; the expression of nestin and GFAP was detected by immunostaining study. Double immunofluorescence was carried out between nestin/GS and GFAP/GS.Results One day after the birth, nestin positive cells were found in the whole retinal neuroblast layers with elongated retinal progenitor cells; the GFAP positive astrocytes were observed in the inner retina. One week after the birth, Müller glial cells expressed GS and nestin but not GFAP; GFAP positive cells localized in the inner retina.Two to 12 weeks after the birth, the expression of nestin in Müller cells decreased and even disappeared; the expression of GFAP in astrocytes didn't change much. The Müller cells expressed nestin but no GFAP in vitro. The expression of nestin and GFAP mRNA in retina was accordant with the results of immunofluorescence staining.Conclusion In the developing retina, the expression of nestin in Müller cells decreases gradually, and no expression of nestin can be found in adult rats; the expression of GFAP can't be observed in Müller cells in neonatal and adult rats.
Objective To observe the expression of related proteins of retina after subretinal implantation with inactive chips.Methods A total of 27 healthy adult New Zealand white rabbits were randomly divided into three groups: operation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina;shamoperation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina which was taken out immediately;the control group (3 rabbits). Animals were sacrified for immunohistological study 7,15,30 and 60 days after surgery.The rabbits in control group group were sacrified for immunohistological study after bred for 30 days.The expressions of glial fibrillary acidic protein (GFAP) and brain derived neurotrophic facor (BDNF) were observed.Results In operation group, the outer nulear layer of retina thinned, and the cells in the inner nulear layer was disorganized 7,15,and 30 days after the surgery;glial cells proliferated 60 days after surgery; the positive expression of BDNF and GFAP was more than that in the shamoperation and control group.In shamoperation group, the positive expression of BDNF and GFAP was more than that in the control group.No obvious difference of expression of BDNF and GFAP between each time point groups was found.Conclusions The expression of neroprotective related proteins increased after subretinal implantation with inactive chips suggests that limited neuroprotective effects might be led by the implantation.
ObjectiveTo observe the role of Notch signaling pathway inhibitor in differentiation process of stem cells derived from retinal Müller cells into the ganglion cell. MethodsRetinas of Sprague Dawley rat at postnatal 10-20 days were dissociated from eye balls. The third passage of Müller cells was used in this experiment, which cultured by repeated incomplete pancreatic enzyme digestion method. The retinal Müller cells were induced in the serum-free dedifferentiation medium. The cell proliferation state was observed under an inverted microscope. The expression of the specific markers Nestin and Ki-67 of retinal stem cells was measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The positive rate of nucleus was detected by Edu. The retinal stem cells was divided into Gamma secretase inhibtor-I (GSI) group and control group, the rate of ganglion cells was counted by using immunofluorescence staining. ResultsThe cell proliferation had gathered to form a sphere. Immunofluorescence staining showed that the expressions of Nestin and Ki-67 were (92.94±6.48%) and (85.96±6.04%) respectively. Edu positive rate of nucleus was (82.80±6.65)%. RT-PCR and Western blot further confirmed the high expression of Nestin and Ki-67 in the cell spheres but not in the Müller cells. The positive rate of ganglion cells were (16.98±2.87)% and (11.17±0.71)% in GSI group and control group respectively, with the significant difference (t=3.210, P=0.002). ConclusionNotch signaling pathway is an important regulatory gene in stem cells differentiated into retinal ganglion cell.
ObjectiveTo investigate the effects of FTY720 on retinal photoreceptor cells and microglial following light-induced degeneration in rat retina. Methods120 Sprague-Dawley rats were randomly divided into four groups including FTY720 group, solvent control group, model group and normal group. The rats of normal group were not intervened. The FTY720 group, solvent control group and model group establish retinal light injury mode. FTY720 was injected into abdominal cavity of the rats in FTY720 group 0.5 hours before light exposure. 50% dimethylsulfoxide was injected into abdominal cavity of the rats in solvent control group. The expressions of microglial cells in rat retinal were quantified using flow cytometry, the expressions of interleukin (IL)-1βwere examined by enzyme-linked immuno sorbent assay at 6 hours, 1 day, 3 days, 7 days after light exposure. The apoptosis of retinal photoreceptor cells were measured by terminal-deoxynucleoitidyl transferase mediated nick end labeling at 1 day after light exposure. The morphological change of retinal were viewed by haematoxylin and eosin staining at 7 days after light exposure. ResultsThe expressions of microgilal and IL-1βbegan to rise at 1 day after light exposure, reached at peak at 3 days and decreased at 7 days. The expressions of IL-1βand microglial in FTY720 group were significantly lower than solvent control group and model group, but higher than normal group (P < 0.05).One day after exposure to light, the apoptosis cell ratio in normal group, model group, solvent control group and FTY720 group were 0, (87.66±2.50)%, (86.00±2.44)%, (49.66±2.80)%. The apoptosis cell in FTY720 group were higher than normal group, lower than solvent control group and model group (P < 0.05). Seven days after exposure to light, the retinal in normal group was structured and the cell was arranged well, the cell in solvent control group and model group was irregular arrangement and the outer nuclear layer (ONL) was thin after light exposure. The thickness of the ONL in FTY720 group was significantly higher than solvent control group and model group, below normal group. ConclusionFTY720 can prevents retinal photoreceptor cells from apoptosis and inhibits activation of microglial.
Objective:To study combination effects of gamma;-ray radiation and hyperthermia on the in vitro cell proliferation of cultured human retianl glial cells in order to explore possible application of the combination treatment for proliferative vitreoretinopathy. Methods:Cultured human retinal glial cells were tread by radiation, hyperthermia,or a combination of the two.Cell proliferation was evaluated by MTT method. Results:gamma;-ary irradiation of 100cGy or 300cGy was not effective in suppressing proliferation of the retinal glial cells,neither was the heat treatment at 42℃ or 43℃ for 30 min.Howver,combination of hyperthermia at 42℃ for 30min with 300cGy irradiation suppressed cellular growth of the retinal glial cells to 25.2% of the control.Combination treatment of 43℃，30 min hyperthermia and 300cGy irradiation was more effective. Conclusion:A combination of low dose radiation and mild hyperthermia is effective in the suppression of frowth of cultured human glial cells,and the effects were found to be synergistic.It is expected that the synergistic effects will lower the radiation dose and and also reduce the possible side effects of radiation in the treatment of proliferative vitroretinopathy. (Chin J Ocul Fundus Dis,1998,14:29-32)