ObjectiveTo observe the changes of macular structure and microvessels in eyes with diabetes macular ischemia (DMI). MethodsA retrospective case study. From January 2023 to July 2023, 23 patients of 31 eyes diagnosed with DMI at Tangshan Ophthalmological Hospital were included in this study. Among them, there were 14 males with 23 eyes; Female cases with 8 eyes. Age were (59.5±4.6) years old. According to the DMI grading standard formulated by the research group for early treatment of diabetes retinopathy, the patients were divided into mild DMI group, moderate DMI group, and severe DMI group, with 8, 12, and 11 eyes respectively. The blood flow density (VD), perfusion area (FA), small vessel VD (SVD), inner retinal capillary plexus VD, FA, and outer retinal, choroidal, and ganglion cell complex (GCC) thickness within 1 mm of the macular fovea in retinal superficial vascular plexus (SVP)were measured using a scanning frequency light source optical coherence tomography instrument. The changes in macular structure and microvasculature in the affected eyes of different degrees of DMI groups were compared and observed. Inter group comparisons were conducted using one-way ANOVA or Kruskal Wallis H-test. Spearman correlation analysis was used to analyze the correlation between DMI severity and GCC, outer retina, choroid thickness, VD, FA and SVP VD, SVD and FA in inner retina. ResultsThe GCC (F=70.670), outer retinal thickness (H=12.393), VD (F=105.506), SVD (H=25.300), FA (F=107.655), and VD (H=24.098) and FA (H=25.300) of the retinal SVP in the mild, moderate, and severe DMI groups were compared, and the differences were statistically significant (P＜0.05). There was no statistically significant difference in choroidal thickness (H=2.441, P＞0.05). Pairwise comparison between groups: VD, SVD, FA of GCC thickness and SVP, and VD of inner retina were statistically significant between severe DMI group and moderate DMI group, and between moderate DMI group and mild DMI group (P＜0.05). The thickness of outer retina was statistically significant between severe DMI group and moderate DMI group (P＜0.05). Inner retinal FA: there were statistically significant differences between severe DMI group, moderate DMI group and mild DMI group (P＜0.05). The correlation analysis results showed that GCC (rs=－0.918), outer retinal thickness (rs=－0.448), and inner retinal VD (rs=－0.894) and FA (rs=－0.918), as well as VD (rs=－0.919), SVD (rs=－0.924), and FA (rs=－0.939) of retinal SVP, were all negatively correlated with the degree of DMI (P＜0.05). There was no correlation between choroidal thickness and degree of DMI (rs=－0.081, P＞0.05). ConclusionThe thickness of GCC, outer retina and choroid, the VD, SVD, and FA of the retinal SVP, the VD and FA of inner retina are all reduced in eyes with different degrees of DMI, while all of them are negatively correlated with the degree of DMI, except for choroid thickness.
Objective To observe the effect of polypyramidine tract binding protein-associated splicing factor (PSF) on hydrogen peroxide (H2O2) induced apoptosis of retinal pigment epithelial (RPE) cells in vitro. Methods RPE cells were cultured and divided into a normal group, normal+H2O2 group, Vec+H2O2group, PSF+H2O2 group according to the experimental design. Overexpression of PSF in RPE cells were achieved by pEGFP-PSF plasmid transient transfection into RPE cells, then RPE cells were exposed to H2O2. The morphological changes were observed by hematoxylin-eosin (HE) staining and Live/Dead staining while the survival rate of cells was detected by MTT assay. The effect of PSF on H2O2-induced RPE apoptosis was analyzed by Cell Death Detection ELISA kit. Meanwhile, intracellular reactive oxygen species (ROS) level was detected by using DCFH-DA method. Results Overexpression of PSF could effectively alleviate the morphological changes induced by H2O2 stimulation shown by HE staining, and effectively reduce dead cells number shown by Live/Dead staining. After H2O2 stimulation, the survival rate, apoptosis rate and ROS production level in PSF overexpression group were 0.68±0.12, 0.44±0.08 and 18 616±3 382.54 respectively, showing significant difference in comparison with the vector plasmid group and normal group (P＜0.05). Conclusion PSF overexpression plays a protective role in H2O2-induced apoptosis by inhibiting the production of ROS in RPE cells.
ObjectiveTo observe the protective effect of dl-3-n-Butylphthalide (NBP) on apoptosis of retinal Müller cells induced by hydrogen peroxide (H2O2).MethodsHuman retinal Müller cells cultured in vitro were divided into normal control group, model group (H2O2 group) and experimental group (H2O2+NBP group). The cells in the H2O2 group and H2O2+NBP group were cultured with 200 μmol/L H2O2 for 2 h. Then the culture solution of the H2O2 group replace with complete medium and the H2O2+NBP group replace with complete medium containing 1 μmol/L NBP. The normal control group was a conventional cultured cells. Müller cells were identified by immunofluorescence staining. Hematoxylin-eosin (HE) staining was used to observe the apoptosis morphological changes. MTT assay was used to detect the activity of of retinal Müller cells after after 24 h and 48 h of NBP intervention. Hoechst33258 staining was used to observe the apoptosis. LIVE/DEAD ® cell activity/cytotoxicity kit was used to detect cell viability. Dichlorofluorescein diacetate (DCFH-DA) + endoplasmic reticulum (ER) red fluorescent probe (ER-Tracker Red) double staining was used to observe the expression level of reactive oxygen species (ROS) in ER of cells. One-way ANOVA combined with Dunnett statistical method were used for data analysis.ResultsHE staining showed that the number of cells in H2O2+NBP group was higher than that in H2O2 group. MTT assay showed that after 24 h and 48 h of NBP intervention, the differences in cell viability between the normal control group and the H2O2 group, the H2O2 group and the H2O2+NBP group were statistically significant (t=28.96, 3.658, 47.58, 20.33; P＜0.001, 0.022). The results of Hoechst33258 showed that the nuclear nucleus of a few cells in the H2O2+NBP group was crescent-shaped and the nuclear fragmentation was reduced, and the blue fluorescence of the remaining cells was uniform. The LIVE/DEAD ® cell activity/cytotoxicity kit showed that the number of dead cells with red fluorescence in the H2O2 group increased significantly, and the number of viable cells with green fluorescence decreased significantly. In the H2O2+NBP group, the number of viable cells with green fluorescence increased, and the number of dead cells with red fluorescence decreased. The double staining results of DCFH-DA+ER-Tracker Red showed that the green fluorescence intensity of H2O2 group was significantly enhanced; the green fluorescence intensity of H2O2+NBP group was lower than that of H2O2 group.ConclusionNBP alleviates H2O2-induced apoptosis of human retinal Müller cells by inhibiting ROS production.
ObjectiveTo observe the effect of polypyramidine tract binding protein-associated splicing factor (PSF) towards advanced glycation end products (AGEs) induced the apoptosis of Müller cells in vitro.MethodsExperimental study. Müller cells were cultured and divided into groups according to the project design, plasmid enhanced green fluorescent protein-PSF were transfected into the cells to achieve the overexpression of PSF Müller cells in vitro, then cells were exposed to AGEs and the Morphological changes were observed by HE staining and Hoechst 33258 staining while the survival rate of cells were detected by MTT assay. The effects of PSF on AGEs-induced Müller apoptosis was measured by Cell Death Detection ELISA kit. Meanwhile, 2′,7′-dichlorofluorescin diacetate staining was performed to monitor the protective effects of PSF on AGEs-induced Müller cells ROS.ResultsThe morphology of cells in normal group was full and the cytoplasm staining was uniform. In N+AGEs group and Vec+AGEs group, cell volume decreased, cytoplasm was dense and concentrated, and eosinophilic staining was enhanced. The cell morphology of PSF+AGEs group was still full, with uniform cytoplasm staining and uniform nucleus staining. The viability of N+AGEs group, Vec+AGEs group and PSF+AGEs group were 0.42±0.11, 0.35±0.12 and 0.68±0.12. The apoptosis values were 1.08±0.16, 0.96±0.20 and 0.44±0.08. The intracellular ROS levels were 28 833.67±3 550.06, 28 356.67±4 854.81, 186 163.00±382.54. Compared with N+AGEs group and Vec+AGEs group, the cell viability of PSF+AGEs group was significantly improved (F=20.65, P=0.000), cell apoptosis value (F=43.43, P=0.000) and intracellular ROS level (F=18.86, P=0.000).ConclusionPSF overexpression play a protective role in AGEs-induced apoptosis by inhibiting the production of ROS in Müller cells.