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 study the effect of down-regulation of Claudin-3 mediated by adeno-associated virus (AAV) of shRNA on the cultured retinal ganglion cells (RGCs) in vitro. Methods RGCs isolated from mouse eyes were divided into normal control group, AAV-shScramble group, and AAV-shClaudin-3 group. The RGCs in AAV-shScramble group and AAV-shClaudin3 group were treated with AAV-shScramble and AAV-shClaudin-3 respectively 24 hours after cell seeding. Dynamic live cell fluorescence microscopy was used to observe the transfection efficiency 96 hours after transfection. Immunofluorescent staining of β-tubulin was used to measure the length of RGCs′ axon. 4′, 6-diamidino-2-phenylindole staining was used to observe the nuclei of apoptotic cells. The mRNA level of Claudin-3 and VEGF was measured by real-time polymerase chain reaction. The protein levels of Claudin-3, vascular endothelial growth factor (VEGF), Bcl-2 and Caspase-3 was determined by Western blot. Results The positive transfection rate was more than 50% in both AAV-shScramble group and AAV-shClaudin-3 group. The length of RGCs' axon in AAV-shClaudin-3 group was shorter than that in normal control group and AAV-shScramble group (F=22 363.274,P＜0.05). Down-regulation of Claudin-3 accelerated RGCs' apoptosis with nuclei shrinkage, tapering, and nucleolus formation of apoptotic bodies. The mRNA levels of Claudin-3 and VEGF in AAV-shClaudin-3 group were lower than those in normal control group and AAV-shScramble group (F=257.408, 160.533;P＜0.05). The protein levels of Claudin-3, VEGF and Bcl-2 in AAV-shClaudin-3 group were lower than those in normal control group and AAV-shScramble group (F=129.671, 420.552, 62.669;P＜0.05), while the protein level of Caspase-3 in AAV-shClaudin-3 group was higher than that in normal control group and AAV-shScramble group (F=231.348,P＜0.05). Conclusion Down-regulation of Claudin-3 increases the expression of Caspase-3, reduces the expression of VEGF and Bcl-2, accelerates RGCs' apoptosis and inhibit the RGCs' axon growth.
[Abstract]Objective To observe the clinical and imaging features of non-arteriotic central retinal artery occlusion (NA-CRAO) with internal boundary membrane detachment (ILMD), and to analyze its relationship with visual prognosis. MethodsA retrospective clinical study. A total of 88 patients with NA-CRAO hospitalized in Department of Ophtalmology, Xi'an People's Hospital (Xi'an Fourth Hospital) from January 2014 to June 2023 were included in the study. Best corrected visual acuity (BCVA), optical coherence tomography (OCT) and fluorescein fundus angiography (FFA) were performed. The BCVA test used the international standard visual acuity chart, which was statistically converted to the logMAR visual acuity. OCT observed the presence of ILMD and the thickening of the inner retina and the disappearance of anatomical stratification. FFA recorded arm-retinal circulation time (A-Rct) and retinal arterion-distal filling time (FT), and observed ciliary retinal artery, fluorescein retrograde filling, cotton spots, luciferin nodal filling, macular non-perfusion, capillary fluorescein leakage, optic disc strong fluorescence, choroidal background weak fluorescence and other characteristics. According to whether there was ILMD, the patients were divided into ILMD group and non-ILMD group, with 44 cases and 44 eyes respectively. The two groups received the same treatment. The follow-up time was 30 days after treatment. The clinical, FFA characteristics and BCVA before and after treatment were compared between the two groups. t-test was used for comparison between groups. ResultsIn ILMD group and non-ILMD group, there were 43 cases of male and 1 case of female, respectively, and the proportion of male was significantly higher than that of female. Before and after treatment, the logMAR BCVA of ILMD group and non-ILMD group were 2.35±0.42, 2.01±0.46, 1.47±0.60, 0.77±0.49, respectively. There were significant differences in logMAR BCVA between the two groups before and after treatment (t=8.025, 12.358; P＜0.001). Before treatment, A-Rct and FT in ILMD group were longer than those in non-ILMD group, and the difference was statistically significant (t=3.052, 3.385; P＜0.05). After treatment, there was no significant difference (t=1.040, 1.447; P＞0.05). The proportion of ciliary retinal artery and cotton plaque in ILMD group was lower than that in non-ILMD group. There was no significant difference in ciliary retinal artery between the two groups (χ2=－0.961, P＞0.05), but there was a significant difference in cotton wool plaque between the two groups (χ2=－3.364, P＜0.05). Compared to the non-ILMD group, The proportion of retrograde fluorescein filling in retinal artery (χ2=－2.846), segment filling (χ2=－3.907), macular non-perfusion (χ2=－6.656), capillary fluorescein leakage (χ2=－4.367), optic disc strong fluorescence (χ2=－3.525) and choroidal background weak fluorescence (χ2=－2.276) increased, the difference was statistically significant (P＜0.05). ConclusionsIn patients with NA-CRAO, compared with those without ILMD, those with ILMD have more severe retinal ischemia and worse BCVA before and after treatment. ILMD is one of the poor prognostic markers of NA-CRAO vision.