| Objective:To establish the model of oxygen-induced mouse retinopathy,investigate the effect of Cathepsin B on JAK2/STAT3 signaling pathway,and further explore the mechanism of retinal neovascularization.Methods:44 7-day-old healthy C57BL/6J mice were randomly divided into normal control group(22 eyes of 11 mice)and hyperoxia treatment group(66 eyes of 33 mice).The mice in the normal control group were reared in the natural environment together with their mothers.The others together with their mothers were put in an oxygen chamber with an oxygen volume fraction of(75±2)% for 5 days and then sent back to the natural environment for the OIR model.The mice of hyperoxia treatment group were randomly assigned into model control group,experimental control group and experimental group with 22 eyes of 11 mice in each group.The mice in the normal control group and the model control group were not give any drug intervention.While the mice in the experimental control group and the experimental group received intravitreal injection of DMSO and CA-074 Me dissolved in DMSO 1 ?l,respectively.After 5 days for treatment,the neovessels were observed by FITCdextran retinal angiography in 17-day-old mice.The mRNA expression levels of JAK2 and STAT3 were performed by Real-time PCR;the protein expression levels were detected by Western blot.All data were presented with mean±standard deviation.Univariate anova was used to compare the overall difference among all groups.When the difference was statistically significant,SNK-q test was further used for multiple comparisons between each two groups.Results:(1)Under fluorescence microscope,the retinal blood vessels in the normal control group were soft and clear,and without ischemia area,non-perfusion area and neovascularization clusters.In the model control group and experimental control group,the vessels were tortuous with obvious neovascularization clusters.The retinal blood vessels in the experimental group were relatively clear,and the ischemia area and non-perfusion area was significantly less.(2)There was a significant difference of the mRNA expression levels of Cathepsin B?JAK2 and STAT3 in the total mean of each group(F=25.23,P<0.001;F=24.86,P<0.001;F=24.22,P<0.001).The expression levels of Cathepsin B?JAK2 and STAT3 mRNA in the retina of the model control group and the experimental control group were(9.92±3.30?3.79 ± 1.66?1.94 ± 0.87,6.36 ± 4.15?2.61 ± 1.02?1.15 ± 0.58),there was no significant difference between them(P>0.05).The expression levels of Cathepsin B?JAK2 and STAT3 mRNA in the retina of the normal control group and the experimental group were(0.260.11?0.12 0.04?0.05 0.02,0.48 0.29?0.54 0.30?0.12 0.07),there was no significant difference between them(P>0.05).After comparison between the other two groups,the difference was statistically significant(P<0.05).(3)There was a significant difference of the protein expression levels of Cathepsin B?JAK2 and STAT3 in the total mean of each group(F=43.86,P<0.001;F=53.90,P<0.001;F=35.87,P<0.001).The expression levels of Cathepsin B?JAK2 and STAT3 protein in the retina of the model control group and the experimental control group were(0.97± 0.13?1.01±0.09?1.02 ± 0.04,0.97 ± 0.13?0.94 ± 0.09?1.05 ± 0.04),there was no significant difference between them(P>0.05).The expression levels of Cathepsin B?JAK2 and STAT3 protein in the retina of the normal control group and the experimental group were(0.30±0.10?0.38± 0.15?0.32 ± 0.11,0.50 ± 0.11?0.41 ± 0.11?0.50 ± 0.28),there was no significant difference between them(P>0.05).After comparison between the other two groups,the difference was statistically significant(P<0.05).Conclusion:Cathepsin B may up-regulate the JAK2/STAT3 signaling pathway promote retinal neovascularization by in the retinal neovascularization of mice induced by hyperoxia. |
PDF Full Text Request