Objective To observe the morphological changes of macular capillary in type 2 diabetic mellitus (DM) patients without clinical features of diabetic retinopathy (DR) by optical coherence tomography angiography (OCTA). Methods This is a prospective clinical case-control study. Forty-three eyes of 22 patients with DM without clinical features of DR (case group) and 40 control eyes of 20 age- and sex-matched healthy physical examination subjects (control group) were enrolled in this study. All subjects underwent OCTA examination with mode of retinal blood flow imaging, macular 3 mm×3 mm and 6 mm×6 mm area, signal strength ＞45. Foveal avascular zone (FAZ) area, foveal capillary density, parafovea capillary non-perfusion, and micro-aneurysm in shallow capillary vessel layer were evaluated. Results In case group, the mean FAZ area was (0.397±0.141) mm2 and the mean foveal capillary density was (44.6±0.62) %. In control group, the mean FAZ area was (0.253±0.112) mm2 and the mean foveal capillary density was (48.6±0.58) %. FAZ area of eyes in case group was larger than that in control group (t=1.017,P＜0.05). There was no difference of foveal capillary density between two groups (t=1.499,P＞0.05). The spider web-like FAZ and normal foveolar avascular zone were observed in eyes of control group. The parafovea capillary non-perfusion, abnormal foveolar avascular zone, micro-aneurysm and tortuosity of vessels were observed in eyes of case group. Parafovea capillary non-perfusion (χ2=4.542), micro-aneurysms (χ2=5.183) were seen more often in case group than control group (P＜0.05). Conclusion Type 2 DM patients have abnormal retinal vascular microcirculation before DR using OCTA, including larger FAZ area, parafovea capillary non-perfusion, abnormal foveolar avascular zone, micro-aneurysm and tortuosity of vessels.
ObjectiveTo observe the outcome of scleral buckle and vitrectomy for familial exudative vitreoretinopathy (FEVR) associated rhegmatogenous retinal detachment (RRD) with different stages. MethodsTwenty eyes in 19 patients were included in this study. All the eyes were staged according to the staging system of FEVR. There are 7 eyes at stage 3A, 4 eyes at stage 4A, 6 eyes at stage 4B, and 3 eyes at stage 5. According to classification of retinal detachment (RD) with proliferative vitreoretinopathy (PVR), PVR B was in 5 eyes, PVR C1 in 2 eyes, PVR C2 in 3 eyes, PVR C3 in 7 eyes, PVR D1 in 3eyes. Retinal holes responsible for the RD could be found in every case. Scleral buckle or vitrectomy were chosen according to FEVR staging, PVR classification, location of retinal breaks, extent of RD.Ten eyes (stage 3A in 7 eyes, stage 4A in 3 eyes;PVR B in 5 eyes, PVR C1 in 2 eyes, PVR C2 in 3 eyes) were undergone scleral buckle, the mean preoperative minimum resolution angle in logarithmic (logMAR) best corrected visual acuity (BCVA) is 0.60±0.32.Ten eyes (stage 4A in 1 eyes,stage 4B in 6 eyes,stage 5 in 3 eyes;PVR C2 in 1 eyes,PVR C3 in 6 eyes,PVR D1 in 3 eyes) were undergone vitrectomy, the mean preoperative logMAR BCVA is 1.81±0.53. The mean follow up was(20.20±7.25) months, range 3 to 30 months. Surgical outcome were estimated by the average number of operation, reattachment of retina and BCVA. ResultsFinal retinal attachment was obtained in 100% of all 20 eyes. The mean postoperative logMAR BCVA of scleral buckle group (0.34±0.32) is improved than preoperative BCVA, the difference wan statistically significant (t=2.932, P=0.017). The mean postoperative logMAR BCVA of vitrectomy group (1.42±0.64) is not changed compare with preoperative BCVA (t=1.812,P=0.103).The mean number of operation of scleral buckle group (1.10±0.32) is less than vitrectomy group's (2.20±0.42),the difference wan statistically significant (t=6.588, P=0.000). ConclusionsAmong the patients whose FEVR staging is less than 4A and PVR classification is less than C3,epiretinal membranes or subretinal membranes appears mild, and scleral buckle can achieve high success rate with less number of operations,and the BCVA is improved in most of the cases. For the patients whose FEVR staging is more than 4B and PVR classification is more than C3, proliferative vitreoretinopathy seems to be serious, retina can be effectively reattached via vitrectomy, however, the number of operations required is multiple, and the BCVA is probably unimproved after operation.
ObjectiveTo observe the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells (hUCMSC) on the expression of vascular endothelial growth factor (VEGF) A in blue light injured human retinal pigment epithelial (RPE) cells. MethodshUCMSC were cultured with exo-free fetal bovine serum for 48 hours, and then the supernatants were collected to isolate and purify exosomes by gradient ultracentrifugation method. Transmission electron microscopy was used to identify the morphology of exosomes. Surface specific maker protein CD63 and CD90 were detected via Western blot. Cultured ARPE-19 cells were divided into normal control group, blue light injured group and hUCMSC exosomes treated group. Cells were exposed to the blue light at the intensity of (2000±500) Lux for 12 hours to establish the light injured models. The cells of hUCMSC exosomes treated group were treated by different concentrations of exosomes for 8, 16, 24 hours. The mRNA and protein of VEGF-A were determined by real time-polymerase chain reaction and Western blot. Immunofluorescence assay were used to detect the expression levels of VEGF-A. ResultshUCMSC exosomes were successfully isolated, they exhibited round or oval shape and their diameter ranged from 50 to 100 nm with membrane structure through electron microscope. hUCMSC exosomes expressed the common surface marker protein CD63 and the surface marker protein CD90 of hUCMSC. The protein and mRNA level of VEGF A in the blue light injured group increased significantly compared to that in normal control group (t=-16.553, -19.456; P < 0.05). After treating with low, middle and high concentration of hUCMSC exosomes for 8, 16 and 24 hours, the protein and mRNA level of VEGF A of injured RPE were significantly decreased (P < 0.05). With the treated time and concentration of hUCMSC exosomes improved, the protein and mRNA level of VEGF A of injured RPE gradually decreased (P < 0.05). Immunofluorescence assay showed the protein level of VEGF-A of injured RPE gradually decreased with the same concentration of hUCMSC exosomes treated over time. ConclusionhUCMSC exosomes can effectively down-regulate the mRNA and protein level of VEGF-A in blue light injured RPE, the effect depends on the concentration and treated time of hUCMSC exosomes.
Objective To investigate the effects of exosomes from cultured human retinal pigment epithelium (ARPE-19) cells affected by oxidative stress on the proliferation and expression of vascular endothelial growth factor-A (VEGF-A) and Akt of ARPE-19 cells. Methods Culture ARPE-19 cells. The concentration of 2.5 μmol/L rotenone was selected to simulate oxidative stress and isolated ARPE-19-exosome. Exosomes were isolated by ExoQuick exosome precipitation solution. Transmission electron microscopy was used to identify the morphology of exosomes. Western blot was used to detect exosomes’ surface-specific maker protein CD63. ARPE-19 cells affected by oxidative stress were cultured with exosome as experimental group, normal ARPE-19 cells were cultured with exosome as control group. The cell proliferation was examined by methyl thiazolyl tetrazolium assay. Western blot and immunofluorescence assay were used to detect the expression levels of VEGF-A and Akt protein. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the levels of VEGF-A mRNA and Akt mRNA. Results The diameter of normal ARPE-19-exosomes ranged from 50 to 150 nm. The isolated exosomes expressed CD63. AREP-19 cells were cultured with ARPE-19 (affected by rotenone)-exosome, the cell viability in experimental group was significantly reduced than in the control group. Green fluorescence was observed in the cytoplasm under fluorescence microscope. Compared with the control group, VEGF-A was up-regulated expressed and Akt was down-regulated expressed. Western blot results showed that, VEGF-A protein expression in the experimental group were higher than the control group. Akt protein expression in the experimental group were less than the control group. The difference was statically significant (t=3.822, 6.527;P＜0.05). RT-PCR results showed that VEGF-A mRNA expression levels was higher in the experimental group than the control group. Akt mRNA expression levels was lower in the experimental group than the control group. The difference was statically significant (t=8.805, −7.823;P＜0.05). Conclusions Exosomes from ARPE-19 cells affected by oxidative stress inhibit the proliferation of normal ARPE-19 cells, increase the expression of VEGF-A and reduce the expression of Akt.