Objective To evaluate the inhibited effects of small interfering RNA targeting Rac1 (Rac1-siRNA) on rat retinal neovascularization in retinae. Methods Retinal vein occlusion was induced by retinal photodynamic medthod in 25 Sprague-Dawley rats. Rac1-siRNA vector DNA was injected into the vitrous of one eye of those rats (gene intervention group), and empty vector DNA was injected into the fellow eye (blank control group). Rac1-siRNA vector was injected in other 25 SD rats without retinal vein occlusion (blank intervention group). Two weeks after injection, fluorescein isothiocyanate (FITC)-dextran was perfused into the hearts of all the rats, and the retinal wholemount was made to observe the neovascularization. The numbers of endothelial cells which break through the internal limiting membrane were counted after hematoxylin-eosin staining. Results A massive of neovascularization and FITC leakage were found in blank control group. Small part of neovascularization and a little FITC leakage were observed in the gene intervention group. Retinal vessels were normal in blank intervention group. Compared with blank contrast group and blank intervention group, the difference of the mean numbers of endothelial cells which broke through the internal limiting membrane in the gene intervention group was significant（t=? P=0.000??lt;0.05）. Conclusion Rac1-siRNA can inhibit retinal neovascularization induced by retinal vein occlusion in rats.
Objective To investigate the protective effect of Niacin on blood-retina barrier (BRB) in diabetic rats and related mechanism. Methods The male Wistar rats (60) were divided into control (CON) group, diabetes (DM) group and Niacin-treated (NA) group, 20 rats in each group. Rats diabetes models were induced with streptozotocin injection. Niacin (40 mg/kg·d) was administrated orally everyday in Niacin-treated group until sacrificed after 3 months. Pathological outcomes, total cholesterol (TC) and high-density lipoprotein (HDL) were evaluated at month 3. Optical microscopy was used to observe the retinal structure. The integrity of BRB and the vascular permeability was quantified by analyzing albumin leakage using Evans blue (EB) method. The relative expressions of Claudin-5, Occludin, zonula occluden (ZO)-1 and GPR109A mRNA in rat retinas were detected by reverse transcription PCR (RT-PCR) and relative expression of GPR109A, tumor necrosis factor (TNF)-α and interleukin (IL)-6 by Western blot. Results Compared to CON group, the TC content was increased and HDL content was decreased in DM group (t=4.034, 5.831; P < 0.05). Compared to DM group, the TC content was decreased and HDL content was increased in NA group (t=6.868, 3.369; P < 0.05). The retinal structure of CON group was normal. Pathological changes were found in the DM group, such as tumescent nuclei and disorganized structures. The retinal structure of NA group was similar to the control group. Evans blue dye that the microvascular leakage in DM group was increased compared with CON group (t=24.712, P < 0.05), while in NA group was decreased compared with DM group (t=16.414, P < 0.05). The mRNA expression of Occludin, Claudin-5, ZO-1 in DM group were decreased compared with CON group (t=11.422, 12.638, 12.060; P < 0.05), while in NA group were increased compared with DM group (t=5.278, 3.952, 8.030; P < 0.05). The mRNA expression of GPR109A in NA group were increased compared with DM group (t=5.053, P < 0.05). The protein expression of GPR109A, IL-6, TNF-αin DM group were increased compared with CON group (t=4.915, 11.106, 6.582; P < 0.05). Compared to DM group, the protein expression of GPR109A was increased (t=5.806, P < 0.05), while the protein expression of IL-6 and TNF-α were decreased (t=10.131, 5.017; P < 0.05). Conclusion Niacin has the protective effect for BRB by up-regulating GPR109A expression which may suppress inflammation.
Objective To investigate the effects of lights with different wavelength on the retina of rd12 and C57BL/6J mice. Methods Thirty two rd12 mice and C57BL/6J mice were randomly divided into the control group, white light group, midwavelength light (505 nm) group and shortwavelength light (405 nm) group, with eight mice in each group. Besides the control group, other groups were exposed to cycle illuminations ［12 hours dark, 12 hours (800plusmn;130) Lux］ for seven days to establish the model of retinal light damage. Electroretinogram (ERG) responses of all mice were recorded at the day before illumination and 1st, 4th and 7th days after illumination. The eyes were enucleated at 7th days after illumination to assess levels of reactive oxygen species (ROS), expression of peroxiredoxin 6 (PRDX6), and activity of caspase-3. Results ERG amplitudes of all groups declined gradually in C57BL/6J mice, and the most significant effects was found in the short-wavelength light group. The amplitudes of photopic b-wave were significantly different at 1st, 4th and 7th days (F=4.412, 5.082, 9.980；P＜0.01). The amplitudes of cone b-wave of the four groups decreased to (85plusmn;10) %, (70plusmn;19) %, (57plusmn;22) % and (46plusmn;19) % at 7th days, respectively, and were significantly different between white light group and short-wavelength light group(t=3.19,P＜0.01). The levels of ROS were significantly different in rd12 mice (F=16.08,P＜0.01), and elevated obviously in shortwavelength light group. The expressions of PRDX6 of retina were significantly different in rd12 mice (F=7.214,P＜0.05), and were decreased obviously in short-wavelength light group. The caspase-3 relative activity was significantly different in rd12 retina (F=7.530,P＜0.05); but there was no significant difference in C57BL/6J mice (F=3.625, 1.993, 1.133; P＞0.05).The caspase-3 relative activity were significant different between rd12 mice and C57BL/6J mice in short wavelength light group (t=5.474,P＜0.05). Conclusions Short-wavelength light can induce retinal damage of mouse retina, especially in rd12 mouse. The retinal light damage possibly relates to the oxidative damage.
Objective To investigate the inhibitory effects of IBI302 on experimental choroidal neovascularization (CNV). Methods Affinity of IBI302 to vascular endothelial growth factor (VEGF) family cytokines (including VEGF-A165, VEGF-A121 and placental growth factor PlGF) and complements (C3b, C4b) was determined by enzyme-linked immunosorbent assay (ELISA). The antagonist effect of IBI302 on VEGF was measured by proliferation, migration and tube formation tests of human umbilical vein endothelial cells (HUVEC). The anti-complement activity of IBI302 was measured by hemolysis test mediated by complement classical pathway and alternative pathway. Rhesus laser-induced CNV model was divided into 5 groups including model control group, bevacizumab group, IBI302 0.25 mg group, IBI302 0.50 mg group and IBI302 1.25 mg group. Fluorescein angiography and optical coherence tomography were performed on these monkeys at 14 and 28 days after drug delivery to observe the fluorescein leakage area and retinal thickness. The aqueous VEGF concentration was measured at 29 days after drug delivery. Results IBI302 showed good affinity to VEGF-A165, VEGF-A121 and PlGF, as well as C3b and C4b. IBI302 significantly inhibited the proliferation, migration and tube formation of HUVEC induced by VEGF-A165. IBI302 inhibited the hemolysis induced by complements obviously. At 14 and 28 days after drug delivery, the area of fluorescein leakage and retinal thickness in IBI302 0.25 mg group, IBI302 0.50 mg group, IBI302 1.25 mg group were reduced. The differences of the area of fluorescein leakage and retinal thickness in three IBI302 groups were not significant (P > 0.05). At 29 days after drug delivery, the VEGF concentration in the aqueous of rhesus monkey in bevacizumab group [(38.644±6.521) pg/ml] was decreased than that in model control group [(94.203±17.360) pg/ml], the difference was significant (P < 0.05). The VEGF concentration in the aqueous of rhesus monkey in three IBI302 groups were less than 31.300 pg/ml. Conclusion IBI302 inhibited experimental CNV through blocking the activity of VEGF and complement.
Objective To construct small hairpin RNA (shRNA) expression plasmid targeting rat opticin gene.Methods Four pairs of opticin oligonucleotides were synthesized and inserted into the plasmid vector, resulting into four plasmids: shRNA-1, shRNA-2, shRNA-3 and shRNA-4. Then the four constructed shRNA expression vectors and empty vector were transfected into rat ciliary non-pigment epithelium (NPE) cells by lipofectmaine 2000. Nontransfected NPE cells were set as control group.The expression of opticin mRNA and protein were measured by Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot respectively.Results The opticin mRNA expression of the shRNA-1,shRNA-2,shRNA-3,shRNA-4 group were decreased compared with the control group (F=10.239，P＝0.000)；the inhibitory rate were 85.7%，62.87%，54.87% and 48.77% respectively.The opticin protein expression of the shRNA-1,shRNA-2,shRNA-3,shRNA-4 group were also decreased compared with the control group (F=17.870，P=0.000)；the inhibitory rate were 78.7%，34.6%，31.1% and 16.8% respectively.Conclusions The shRNA-1 expression plasmid has most potent inhibitory effect on opticin expression in rat ciliary NPE cells.
Objective In order to study the mechanism of cholesterol gallstone formation through rabbit model which was induced by high cholesterol diet (HCD)Methods the activities of the high density lipoprotein receptor (HDLR) and low density lipoprotein receptor (LDLR) of hepatocytes were investigated. Results The results were as follows: The HDLR activity increased significantly after taking HCD for one week, at the same time, the LDLR activity only increased slightly. Thereafter, the activities of HDLR and LDLR all decreased markedly. As the time of animals taking HCD went on, serum total cholesterol, LDL cholesterol and hepatic cholesterol increased, but bile acids of biliary tract decreased gradually. Conclusion The results suggest that the changes of HDLR and LDLR activities of hepatocytes had no significant effect on bile cholesterol and the decreased HDLR and LDLR activities may cause the reduction some of substrate for bile acids synthesise and play an important role in the formation of gallstone.
ObjectiveTo observe the expression of interleukin (IL)-17, IL-4 and interferon γ (IFN-γ) in experimental autoimmune uveoretinitis (EAU). MethodsC57BL/6 mice were immunized with interphotoreceptor retinoid-binding protein 1-20 to induce EAU. The inflammatory reaction before and on 7, 14, 21, 28 days after immunization were observed. The level of IL-17, IL-4 and IFN-γ in the serum were measured by enzyme-linked immune sorbent assay (ELISA). mRNA and protein expression of spleen and retina were analysed using quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blot at the same time, respectively. ResultsThe most serious inflammatory reaction occurred at the 14th day after immunization. The highest level of IFN-γ in serum, highest mRNA and protein expression of IFN-γ in spleen and retina of mice occurred at day 7 after being immunized. The highest level of IL-17, IL-4 in serum, highest mRNA and protein expression of IL-17, IL-4 in spleen and retina of mice occurred at day 14 after being immunized. The increase degree of IL-17 was more than IFN-γ and IL-4. At 7, 14 and 21 days after immunization, compared with the pre-immunization, the level of IL-17, IL-4, IFN-γ in serum of mice were significantly increased (F=1 817.346, 268.600, 164.621; P < 0.05). There was no difference in the levels of IL-17, IL-4, IFN-γin serum of mice between pre-and 28 days after immunization (P > 0.05). At 7, 14 and 21 days after immunization, compared with the pre-immunization, the protein expression of IL-17, IL-4, IFN-γ in spleen (F=312.67, 114.250, 216.220) and retina (F=271.504, 85.370, 80.722) of mice were significantly increased (P < 0.05). There was no difference in protein expression of IL-17, IL-4, IFN-γ in spleen and retina of mice between pre-and 28 days after immunization (P > 0.05). ConclusionsThere were IL-17, IL-4 and IFN-γ expression in EAU. IL-17, IL-4 and IFN-γ play a key role in the occurrence and development of the EAU.
Taking Wistar rats and pigs as models, the basic fibroblast growth factor (bFGF) was studied on wound healing. Five rats and five pigs were used in the experiment. Each rat had 2 roundshapedwound (1.8cm in diameter) and each pig had 4 wounds of the same size as that ofthe rat. One wound of each rat and 2 wound of each pig were dressed with bFGF saline (60U/cm2). While the other wounds of the rats and pigs were dressed with normal saline as control. The wounds treated with bFGF were completely covered with granulation tissue on the 7th day after injury, and in 14 days the wounds were almost completely covered by epithelium. The bFGF would enhance the growth of theepithelial cells, reepithelization of the wound and the tensile strength of thetissue. It was concluded that the bFGF could promote skin regeneration, whichmight be the direct action of bFGF on the bFGF receptors in the basic cells of skin.