Objective To investigate the correlation of expression of Fas/Fas ligand (FasL) and apoptosis in retinoblastoma (RB). Methods The expression and distribution of Fas/FasL were detected by using immunohistochemical staining in 32 cases of RB. Light microsc opy (32 cases), electron microscopy (4 cases) and TdT mediated biotin-d UTP nick-end labeling (TUNEL) (12 cases) were used to study apoptosis in RB. Results Apoptotic RB cells mostly located at RB regress area. Chromatin margination and apoptotic bodies were found in RB. TUNEL posi tive labeling cells especially located in tumor regress area. Positive immunola beling for Fas and FasL was found in all RB specimens. There was a highly signi ficant and positive correlation between the expression of Fas/FasL and apoptotic indices (AI) (Plt;0.01 or 0.001). Conclusion The results suggest that apoptotic cell death is prevalent in RB and it may be one type of the most dominant cell death. Fas system may play an important role in oncogenesis and progression of RB, and the up-regulation of Fas system expression might induce RB cell apoptosis. (Chin J Ocul Fundus Dis, 2001,17:21-23)
Objective To further investigate pathologic mechanism of retinal phototrauma. Methods Twenty Wistar rats were divided into control and experimental groups.Their eyes were extracted in 12,24 and 36 hours after light exposure.HE stained retina samples were examined and TDT-mediated dUTP nick end labelling(TUNEL)method was employed to distinguish apoptotic cells. Results After 12-hour light exposure,slight vesiculation was observed in the rod outer segment of the retinas.After 24-hour light exposure,the outer nuclear layer showed predominant fractured and condensed nuclei and fragmented DNA.After 36-hour light exposure,the rod outer and inner segments were lysed and most of the nuclei in the outer nuclear layer were disappeared. Conclusions Apoptosis of photoreceptor cell is one of the important mechanisms which cause experimental retinal photoinjury of rats. (Chin J Ocul Fundus Dis, 1999, 15: 167-169)
Objective To study the expression and its significance of bcl-2 associated death (bad) gene in human optic nerves from traumatic atrophic eyeballs. Methods The optic nerves from 8 normal human donor eyes and 31 traumatic atrophic eyes were studied by immunohistochemistry technique. Results Bad protein was positively expressed in the normal optic nerve myelin sheath and residual myelin portions of optic nerve tissues from traumatic atrophic eyes. The expression of bad protein in the residual portions of myelin sheath was stained significantly ber than that in normal optic nerves (P<0.05)。The pathological durations for ocular atrophy was not co-related with the quantites of expression of bad protein. There was no significant difference between pathogenic causes of ocular atrophies and the quantites of bad expression (P>0.05). Conclusion Bad might possess the function of promoting the optic nerve atrophy processes in traumatic atrophic eyes. (Chin J Ocul Fundus Dis, 2002, 18: 276-278)
Purpose To study the proteins expression of genes related to apoptosis of retinal cells in development of human fetus. Methods Fifty cases of retinas of human fetus aged from 12 to 38 we eks were collected and paraffin embedded sections were made. Immunohistochemical method was used. Results Fas protein was expressed by cells of ganglion cell layer, inner and outer nuclear later, which were just formed on 16th week. It was not expressed until 38th week, Fas(+) staining appeared in layers of retina. Fas-L(+) staining was detected in cells of layers of retina on 26th week and the positive staining located in ganglion cell layer on 32th week. Neuronal fiber layer was Fas-L positive. Bax positive staini ng was detected on 8th week. Bax positive nucleus were observed mainly in GCL and ONL on 16th week. It was in INL on 24th week and in Muuml;ller cells inner terminates on 26th week. After this time, all cells of retina were bax immune ne gative staining. Bcl-2(+) staining appeared in differentiating neuroblastic layer on 16th week. Beginning on 24th week, bcl-2 (+) staining was observed in glial cells of GCL and inner terminates of Muuml;ller cell. Conclusion Apoptosis of developing retinal cell may be Fas/Fas-L independent and bax may be involved in apoptosis of the cells. (Chin J Ocul Fundus Dis, 2001,17:55-57)
Objective To observe the protective effects of Na2SeO3 on the damage of retinal neuron induced by microwave. Methods Cultured fluids of retinal neuron were divided into 4 groups,including 1 group of control, according to the concentration of Na2SeO3 in cultured fluid and then exposed to 30 mW/cm2 microwave for 1 hour.The targets of lipid peroxidation and the concentration of selenium in cells were measured.Apoptosis detection was taken by TUNEL detection kit. Results The activity of SOD and GSH-Px rised,meanwhile the content of MDA and the amount of apoptosis cells decreased in 1times;107 mol/L group compared with the group without Na2SeO3.The other groups was superior in antioxdant capacity to 1times;107 mol/L group. Conclusion Na2SeO3 might be possessed of the effect of protecting the damage of retinal neuron induced by microwave. (Chin J Ocul Fundus Dis,2000,16:97-99)
Objective To investigate the damage to the retinal cells and apoptosis of retinal cells of rats after ischemia-reperfusion insult. Methods The retinal ischemia-reperfusion model was developed by increasing intraocular pressure to 109725 mm Hg in rat eyes. Morphological changes of the rat eyes were observed by means of routine histopathology with HE staining. Apoptosis of the retina was assayed by both DNA fragmentation gel-electrophoresis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL). Results Compared with the normal control, no histopathological changes were revealed in the rat retinas 30 min after the ischemia and then reperfued for 24 h or 48 h. Retinal ganglion cell layer (RGL) and inner plaxiform layer (IPL) of the retina were observed, however, to become significantly thinner 60 min after the ischemia and then reperfued for 24 h or 48 h. Together with the pathological changes DNA ladder pattern was detected in the same group of the rats. Further, immunochemical stain of the eye demonstrated that TUNEL positive cells were localized in RGL and IPL of the retina. Conclusion Ischemia-reperfusion insult of the eye may remarkably damage the retina of the rat eye. The damage to the retinal cells is mainly localized within RGL and IPL and apoptosis is the important mechanism of the retinal disorder. (Chin J Ocul Fundus Dis, 2002, 18: 296-298)
Objective To determine the effects of lensspecific overexpression of OSM on the eye development. Methods A truncated mouse OSM c DNA (661 bp) was linked to the αA-crystallin promoter. Transgenic mice were characterized by routine histological and immunohistochemical techiniques. TUNEL assays were used to de tect cell death. The mRNA expression of caspase-3 was detected by in situhybridization, Rabbit anti-cleavage caspase-3 antibody was used to detectactive capase-3. Results At embryonic day (E) 14.5 and 17.5, expression of the OSM transgenic protein was detected specifically in lens fiber cells. The onset of retinal degeneration in the mid portion of the transgenic retinae was observed started from E17.5. By the time of birth 50% or more of the retinal cells were missing. The OSM transgenic retinal cells underwent apoptosis indicated by TUNEL assays. Most strikingly, activation of caspase-3 protein were observed throughout the transgenic retinas. Conclusions Lens-specific overexpression of OSM activate caspase-3, leading to abnormal eye development,apoptosis and widespread retinal degeneration. (Chin J Ocul Fundus Dis,2003,19:201-268)
Objective To investigate the role of anti apoptosis gene bcl-2 in the survival of cultured uveal melanoma UM cells. Methods Antisense oligodeoxynucleotides (AS-ODN) bcl-2 were delivered with cationic lipid to primary cultured UM cells. The inhibitory effect of AS-ODN bcl-2 on proliferation of UM cells was examined by 3,-4,5 Dimethyliazol-2,5 diphenyl tetrazolium bromide (MTT) method. Using DNA ladder to determine if the UM cells had been apoptotic. Bcl-2 expression was detected by RT-PCR and Westernblot technics. Results The effect of AS-ODN bcl-2 in inhibiting the proliferation of cultured UM cells had opposite relation to dosage. It down regulated the mRNA and protein level of bcl-2 gene, and the sense ODN didn′t have this effect. Conclusion AS-ODN bcl-2 can down regulate bcl-2 expression, inhibits UM cells proliferation and induces apoptosis. (Chin J Ocul Fundus Dis, 2002, 18: 38-41)