ObjectiveTo observe the inhibitory effect of lentivirus mediated small interference RNA (siRNA) targeting cyclic adenosine monophosphate responsive element binding protein 1 (CREB1) on retinal neovascularization (RNV) in mice. MethodsCREB1 siRNA construct was created, screened and packaged to produce CREB1 RNAi-lentivirus. One hundred and forty (5-day-old) C57BL/6J mice were randomly divided into 4 groups including normal group, oxygen induced retinopathy (OIR) group, empty vector group and CREB1 therapy group with 35 mice in each group. Mice in the normal group were kept in normal room air, while in the other three groups retinal neovascularization was induced by hypoxia on postnatal day 7 (P7). The mice in the OIR group were not treated. The mice in the vector group received intravitreal injection of lentivirus-green fluorescent protein (lenti-GFP, 1 μl), and the CREB1 therapy group received CREB1 RNAi-lentivirus (1 μl) on P5.The proliferative neovascular response was quantified by counting the vascular cell nuclei extending breaking through the internal limiting membrane (ILM) and fluorescent angiography. The areas of RNV and non-perfusion region were calculated. The expression of CREB1, phosphorylated-CREB1 (P-CREB1) and vascular endothelial growth factor (VEGF)-A levels, Akt and phosphoinositide 3-kinases (PI3K) in retinas were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot. ResultsThe number of vascular cell nuclei breaking through the ILM of the OIR group and the empty vector group increased significantly compared with the normal group (P<0.05), while obviously decreased in the CREB1 therapy group compared with the OIR group and the empty vector group(P<0.05). The area of RNV and non-perfusion region of the OIR group and the empty vector group increased significantly compared with the normal group, while obviously decreased in the CREB1 therapy group compared with the OIR group and the empty vector group. The difference of area of RNV and non-perfusion region among 4 groups were significant (F=67.220, 110.090; P<0.05). The mRNA expression of CREB1 and protein expression of P-CREB1, the mRNA and protein expression of VEGF-A, Akt, PI3K in the retina were increased significantly in the OIR group and the empty vector group as compared with the normal group, while decreased significantly in the CREB1 therapy group as compared with the OIR group and the empty vector group. The difference of mRNA expression of CREB1, VEGF-A, Akt, PI3K in the retina among 4 groups were significant (F=6.087, 5.464, 6.191, 8.627; P<0.05). The protein expression of P-CREB1, VEGF-A, Akt, PI3K in the retina among 4 groups were significant (F=162.944, 13.861, 19.710, 22.827; P<0.05). ConclusionRNV in the mice is significantly inhibited by intravitreal injection of lentivirus-mediated CREB1 down-regulation.
ObjectiveTo analyze the OCT angiography (OCTA) features of eyes affected with angioid streaks.MethodsRetrospective analysis of 26 patients (52 eyes) diagnosed as angioid streaks by multi-modal imaging in Ophthalmology Department of Yunnan Second People’s Hospital from May 2017 to February 2019 were included in this study. There were 18 males and 8 females, with the mean age of 50.8±6.9 years. All the patients were binocular. There were 34 eyes in 20 patients with CNV. Among them, 13 eyes had a course of disease within 1 month, 16 eyes had a course of disease over 1 month, and 5 eyes were treated with anti-VEGF drugs. All patients were examined by ultra-wide-angle fundus photography, infrared fundus imaging (IR), spectral-domain OCT, FAF and FFA. At the same time, the Heidelberg OCTA instrument was used for OCTA examination. The central wavelength was 840 nm, the acquisition speed was 85,000 times/s, and the width was 45 nm. A 3 mm × 3 mm scan was obtained. Each cube consisted of two 304 B scans of repeated volumes, and motion correction was performed using two orthogonally captured image volume registration. The results of fundus color photography, IR, FAF, FFA, OCT and OCTA were compared and analyzed to summarize the image features of AS and its secondary CNV in OCTA.dus color photography, IR, FAF, FFA, OCT and OCTA were compared and analyzed to summarize the image features of AS and its secondary CNV in OCTA.ResultsAmong 52 eyes, 40 eyes showed choroidal capillary shadows in OCTA, and no obvious abnormal OCTA images in 12 eyes. Ten eyes OCTA showed a vascular network beseide the optic disc, FFA showed fluorescent staining instead of fluorescein leakage. Among the 52 eyes, 34 eyes had secondary macular CNV, and 34 eyes had different forms of CNV. Different forms had a certain correlation with the length of medical history and treatment history. Among them, 13 eyes with short course of disease (less than 1 month) and untreated patients had smaller flower-ring morphology, 16 eyes with longer course (more than 1 month) but no treatment had larger fan-shaped segments, and 5 eyes with anti-VEGF therapy were trimmed after the dendritic shape.ConclusionsAS streaks appeared no blood flow signal area in OCTA, and repairing vascular network beside the optic disc can be observed in some AS patients. The CNV performance with different disease course and treatment experience is different.