ObjectiveTo construct a lentiviral vector carrying rat sirt1 gene and observe the expression of sirt1 in retinal ganglion cell (RGC) of rat. MethodsRat sirt1 cDNA was inserted into pLV5 vector. After identification by sequencing analysis and PCR, the recombinant sirt1expressinglentivirus vector was packaged by cotransfecting 293T cells with packaged plasmid.Then pLV5-sirt1 was used to infect the cultured Sprague-Dawley rat RGC cell in vitro.The expressions of sirt1 protein and mRNA in infected rat RGC were detected by quantitative real-time PCR and Western blot. ResultsThe sirt1 expression vector pLV5 was successful constructed and sequence was proved to be correct. The expression of sirt1 protein and mRNA in RGC was significantly increased than that in cells infected with control lentiviruses(P < 0.05). ConclusionWe have successful constructed a sirt1 expression lentivirus vector pLV5-sirt1 and it can increase the expression of sirt1 protein and mRNA in the rat retinal ganglion cells.
ObjectiveTo observe the expression of Toll-like receptor 4 (TLR4) and inflammatory cytokines, leucocytic density and permeability in retina of diabetic rat. MethodsA total of 106 Brown Norway rats were randomly divided into experimental group and control group with 53 rats in each group. Diabetic model was established in experimental group by intraperitoneal injection of streptozotocin, and control rats received intraperitoneal injection of an equal volume of citric acid-sodium citrate buffer. Four weeks later, the retinas were collected for further analysis. TLR4 RNA and protein expression were measured by quantitative polymerase chain reaction and Western blot. Inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), monocyte chemo-attractant protein-1 (MCP-1), were measured by enzyme-linked immunosorbent assay in rat retina homogenate. Leukocyte density in the retina was measured by acridine orange fundus angiography. The retinal permeability was evaluated by Evans blue (EB) staining. ResultsTLR4 expression was significantly increased in diabetic rats of experimental group compared with non-diabetic rats of control group (F=1.606, 0.789; P < 0.05). Inflammatory cytokines (TNF-α, IL-1β and MCP-1) were significantly increased in retina of diabetic rats of experimental group versus non-diabetic rat of control group (F=24.622, 5.758, 4.829; P < 0.05). The retinal leukocyte density was (6.2±0.5)×10-5, (2.2±0.3)×10-5 cells/pixel2 in experimental and control group respectively, the difference was statistically significant (F=2.025, P < 0.05). The amount of retinal EB leakage was (23.41±4.47), (13.22±3.59) ng/mg in experimental and control group respectively, the difference was statistically significant (F=21.08, P < 0.05). ConclusionTLR4 and inflammatory cytokines expression, leucocytic density and permeability increased significantly in retina of diabetic rat.
Objective To investigate the effects of knocking down Rac1 gene (ras-related C3 botulinum toxin substrate 1) by small hairpin RNA (shRNA) on retinal neovascularization in a mouse model of oxygen-induced retinopathy (OIR). Methods One hundred and eight 7-day-old C57BL/6J mice were divided into three groups randomly.The OIR was induced by Smith protocol in 2 groups. OIR mice received an intravitreal injection of Rac1-shRNA plasmid or the nonsense plasmid in the geneintervention group and control group respectively at the age of postnatal day 11 (P11). Non-OIR mice also received an intravitreal injection of Rac1-shRNA plasmid at P11 as the blankintervention group which lived in the normoxic environment.Retinal neovascularization was investigated on flat-mounts after fluorescence angiography at P15 and P17. Endothelial cell nuclei breaking through the internal limiting membrane were counted on pathological section at P17.The expression of Rac1 and NF-kappa;B p65 subunit was measured by immuohistochemistry, Western blot, real-time polymerase chain reaction (RT-PCR) and in situ hybridization. Results Compared with the blank-control group,the level of Rac1 mRNA in the gene-intervention group decreased obviously（t=4.500，P=0.001）;the retinal non-perfusion areas,fluorescence leakage, neovascularization and the number of endothelial cell nuclei breaking through the internal limiting membrane were reduced significantly（t=6.521,P＜0.001）; the level of NF-kappa;B p65 nuclear translocation decreased（t=16.008,P＜0.001）while the expression of NF-kappa;B p65 mRNA was reduced obviously（t=3.354,P=0.006）, which was positively correlated with the expression of Rac1-mRNA (P=0.012).Conclusion Intravitreal injection of Rac1-shRNA with liposome in mice can effectively inhibit the expression of Rac1,and inhibit the retinal neovascularization under relative hypoxia via blocking the ROS-NF-kappa;B pathway.
Objective To investigate the role of vascular endothelial growth factor ( VEGF) in the pathogenesis of emphysema and its relationship with tumor necrosis factor alpha ( TNF-α) . Methods 48 rats were randomly divided into four groups, ie. a normal control group, an emphysema group, a rhTNFR∶Fc intervention group, and a sham intervention group. The rats in the emphysema group, the rhTNFR: Fc intervention group, and the shamintervention group were exposed to cigarette smoking for 80 days. After 30 days of exposure, rhTNFR: Fc hypodermic injection was administered in the rhTNFR: Fc intervention group while placebo was injected in the sham intervention group as control. Lung tissue sections were stained by hematoxylin and eosin. Mean linear intercept ( MLI) and mean alveolar numbers ( MAN) were measured to estimate the extent of emphysema. The level of TNF-αin serumand BALF, and the level of VEGF in BALF were measured with ELISA. Results In the emphysema group, MLI was higher and MAN was lower than those in the normal control group. Moreover, the levels of TNF-αin serum and BALF were higher, and thelevel of VEGF in BALF was lower significantly ( P lt;0. 05) . After the intervention with rhTNFR∶Fc, MAN increased and the serum TNF-αdecreased significantly compared with the emphysema group ( P lt; 0. 05) .However there were no significant differences in MLI, VEGF, and TNF-α in BALF ( P gt; 0. 05 ) . No correlation was found between the level of TNF-αand VEGF in BALF in the emphysema group. Conclusion VEGF and TNF-αare related to the pathogenesis of emphysema of smoking rats, and may contribute to the development of emphysema in different pathways.
Objective To observe the dynamic expression of nestin and glial fibrilary acidic protein (GFAP) in the development of retina in rats.Methods In 48 Wistar rats, 24 were divided into 8 groups with 3 rats in each according to their age (1 day, 1 week, and 2, 3, 4, 7, 12, and 20 weeks old). The sagittal freezing sections of the eye were made; nestin/glutamine synthetase (GS) and GFAP/GS were stained by immunofluorescence and were observed under the confocal microscope. Total RNA was extracted from 18 rats which were divided into 6 groups according to the age (1 day, 1 week, and 2, 3, 4, and 12 weeks old) with 3 rats in each. The expression of nestin, GAFA and GS mRNA were detected by realtime quantitative reverse transcription polymerase chain reaction (RT-PCR). Müller cells were cultured from postnatal day 7-12 rats; the expression of nestin and GFAP was detected by immunostaining study. Double immunofluorescence was carried out between nestin/GS and GFAP/GS.Results One day after the birth, nestin positive cells were found in the whole retinal neuroblast layers with elongated retinal progenitor cells; the GFAP positive astrocytes were observed in the inner retina. One week after the birth, Müller glial cells expressed GS and nestin but not GFAP; GFAP positive cells localized in the inner retina.Two to 12 weeks after the birth, the expression of nestin in Müller cells decreased and even disappeared; the expression of GFAP in astrocytes didn't change much. The Müller cells expressed nestin but no GFAP in vitro. The expression of nestin and GFAP mRNA in retina was accordant with the results of immunofluorescence staining.Conclusion In the developing retina, the expression of nestin in Müller cells decreases gradually, and no expression of nestin can be found in adult rats; the expression of GFAP can't be observed in Müller cells in neonatal and adult rats.
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 investigate the influence of enamel matrix proteins (EMPs) on the attachment, prol iferation and pre-mRNA of type I collagen synthesis of cultured human dermal fibroblast cells. Methods Human dermal fibroblast cells were obtained from human acrobystia and cultured in DMEM medium with 10% FBS. The 3rd to 6th passage cells were used. Ninety-six-well plates and 6-well plates were pre-coated with different concentrations of EMPs (50, 100, 150 and200 μg/ mL). ① The cell attachment experiment: 0.2 mL cells suspension at the concentration of 1 × 106/mL was added to the pre-coated 96-well plates as the experimental groups (groups A, B, C and D based on different concentrations of EMPs). At 1.5, 3.0, and 4.5 hours after inoculation, the attached cells were measured by MTT method. ② The cell prol iferation experiment: 0.2 mL cells suspension at the concentration of 5 × 104/mL was added to the pre-coated 96-well plates as the experimental groups (groups A1, B1, C1 and D1 based on the different concentrations of EMPs). At 2, 4, 6 and 8 days after inoculation, the cells were measured by MTT method. ③ The synthesis experiment of pre-mRNA: 2 mL cells at the concentration of 1 × 106/mL was added to the pre-coated 6-well plates as the experimental groups (groups A2, B2, C2 and D2 based on different concentrations of EMPs). At 5 days after inoculation, the synthesis of pre-mRNA was measured by RT-PCR method. Human dermal fibroblast cells were added to the un-coated plates as the control groups. Results ① The cell attachment experiment: There were significant differences in attachment cells between the control group, group A and the groups B, C and D (P lt; 0.05). There were no significant difference between group A and control group (P lt; 0.05). ② The cell prol iferation experiment: At 2 days, there were no significant differences in absorbance between the control group and the experimental groups (P gt; 0.05); at 4 days and 6 days, the absorbance of groups B1 (0.598 ± 0.020 and 0.639 ± 0.016 ), C1 (0.582 ± 0.017 and 0.641 ± 0.020) and D1 (0.574 ± 0.021and 0.635 ± 0.021) was significantly higher than that of the control group (0.548 ± 0.021 and 0.605 ± 0.019, P lt; 0.05); at 8 days, the absorbance of group B1 (0.629 ± 0.012) and group C1 (0.631 ± 0.014) was significantly higher than that of the control group (0.606 ± 0.031, P lt; 0.05). ③ The synthesis experiment of pre-mRNA: The synthesis of type I collage pre-mRNA of groups B2, C2 and D2 was significantly higher than that of the control group. Conclusion EMPs stimulate human dermal fibroblast cell attachment, prol iferation and synthesis of type I collage pre-mRNA, and its maximal effect can be achieved at the concentration of 100 μg /mL.
ObjectiveTo observe the expression of heat shock protein 47 (HSP47) and transforming growth factor-β2(TGF-β2) in vitreous specimens and epiretinal membranes of patients with proliferative vitreoretinopathy diseases. MethodsVitreous specimens and epiretinal membranes were obtained from 48 patients (48 eyes) with proliferative vitreoretinopathy (PVR) and 50 patients (50 eyes) with proliferative diabetic retinopathy (PDR). Vitreous specimens and internal limiting membranes were collected from 20 patients (20 eyes) with idiopathic macular hole (IMH) as control group. The expression of HSP47 and TGF-β2 in the vitreous specimens was evaluated using enzyme linked immunosorbent assay. The expression of HSP47, TGF-β2, typesⅠandⅢcollagen in epiretinal membrane and internal limiting membrane specimens were observed for immunohistochemical staining method. The correlation between the positive expression of HSP47 and TGF-β2, typesⅠandⅢcollagen in epiretinal membrane specimens of patients with PVR and PDR were analyzed. ResultsThe expression of HSP47 in vitreous specimens of patients with PVR, PDR and IMH were (212.35±23.32), (231.30±26.79), (171.06±28.91) pg/ml, respectively. The expression of TGF-β2 in vitreous specimens of patients with PVR, PDR and IMH were (1919.96±318.55), (1939.39±177.57), (1194.61±234.20) pg/ml, respectively. The expression of HSP47, TGF-β2 in the vitreous specimens of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=12.952, 34.532;P < 0.01). The epiretinal membrane of patients with PVR and PDR showed markedly increased expression of HSP47, TGF-β2, typesⅠandⅢcollagen in the cytoplasm and extracellular matrix. The expression of HSP47 and typeⅢcollagen was negative and the expression of TGF-β2 was weakly positive and the expression of typesⅠcollagen was positive in internal limiting membrane of patients with IMH. The expression of HSP47, TGF-β2, typesⅠandⅢcollagen in the epiretinal membrane of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=13.469, 18.752, 12.875, 20.358; P < 0.01). The expression of HSP47 was positively correlated with the positive expression of TGF-β2, typesⅠandⅢcollagen in epiretinal membrane specimens of patients with PVR (r=0.475, 0.556, 0.468; P < 0.05) and PDR (r=0.484, 0.589, 0.512; P < 0.05). ConclusionsThis study showed increased consistent expression of HSP47 and TGF-β2 in vitreous and epiretinal membrane specimens of patients with PVR and PDR. Both HSP47 and TGF-β2 were expressed in the cytoplasm and extracellular matrix. HSP47 and TGF-β2 may be involved in the pathological process of PDR and PVR by promoting collagen synthesis.
Objective To investigate the expression of induced heat shock protein (HSP) 70 in ratprime;s retinal neurons (RNs) and Muuml;ller cells, and evaluate the protective effect of HSP 70 on RNs injured with glucose deprivation and glutamate. Methods Ratprime;s RNs and Muuml;ller cells cultured in vitro were treated with heat shock (42℃ for 1 hour), and duration of the expression of HSP70 was detected by immunocytochemical techniques. Viability of the cells was measured by methyl thiazolyl tetrazolium (MTT) chromatometry after incitant toxic injury with glucose deprivation (0.56 mmol/L glucose for 6 hours) and glutamate (100 mu;mol/L for 6 hours). Simultaneously, the expression was interdicted by HSP70. Results Hypereffective expression of HSP70 was found in cultured RNs and Muuml;ller cells after heat shock. The viability of RNs pretreated by heat shock after injured with glucose deprivation and glutamate significantly increased which could be interdicted by HSP70 antibody. Conclusion Hypereffective expression of HSP 70 may be induced by heat shock, which enhances the ability of tolerance of RNs to the incitant toxic injury by glucose deprivation and exitotoxicity. (Chin J Ocul Fundus Dis, 2005,21:110-113)
Objective To clarify the relationship between inhibition of proliferation and cxpression of Ki-67 in cultured human retinal pigment epithelial(RPE) cells. Methods The cultured human RPE cells were treated with daunoblastina at a dose of 180 mu;g/L for 12h.Twenty-four hours later,DNA inhibiting rate was studied by using tritium-labelled thymidine deoxyribose(3H-TdR)incorporation assay.The expression of Ki-67 was evaluated by immunocytochemical staining technique and image analysis system.Flow cytometry was used to analyse cell cycle. Results DNA inhibiting rate was directly proportional to the dosage of daunoblastina.The proportion of the cells positive staining to Ki-67 in the control and the daunoblastina-treated group were 89.3% and 45.6%(Plt;0. 01),and the integral optical density values for expression of Ki-67 in the two groups were 68.1plusmn;6.2 and 27.3plusmn;5.5(Plt;0.01),respectively.The percen tage of cells in G2 phase of cell cycle increased from 8.9% to 29.5%. Conclusion G2 block was induced and poliferation was inhibited by daunoblastina in cultured human RPE cells.There is a relatively good correlation between Ki-67 immunostaining and inhibition of RPE cell proliferation. (Chin J Ocul Fundus Dis，2000，16：1-70)