The Mechanism Of Reduce β2GPI Inhibition Diabetic Retinal Angiogenesis Via The VEGFR-2Ways

ObjectiveDiabetic retinopathy(DR)is one of the major micro vascular complication of diabetes. Proliferative diabetic retinopathy(PDR) with angiogenesis as its characteristic serves as a significant cause for blindness of diabetic patients. Some studies found that vascular endothelial growth factor (VEGF) is involved in the occurrence and development of diabetic retinopathy. Our studies found that reduce β2-glycoprotein I can inhibit the angiogenesis of oxygen-induced retinopathy in newborn mice. So we choose SD rats as our subjects to investigate the effect of reduce β2GPI and β2GPI in diabetic retinal angiogenesis and the possible mechannism.Methods1. Animal model Sprague Dawley rats were randomly divided into two groups. The rats in NC were fed a regular diet. The rats in model group were fed a high fat diet. After8weeks, the index of homeostasis model assessment insulin resistance is evaluated and were given intravenous injection low-dose streptozotocin in model group. At1week after streptozotocin injection, blood were collected from the tail of all rats. If the blood glucose level>16.7mmol/L,we considered the diabetes model to have beem successfully established. The rats were randomly divided into four groups: a normal group, a diabetes group, reduce β2-glycoprotein I treated group, β2-glycoprotein I treated group. After4weeks, the femoral artery of all the rats bled to death. Serum were used to evaluated the liver function, renal function, blood lipid, FBG and fasting palsma insuin. Some of the eyes were soaked in the formaldehyde. The left of them were quickly freezed in the liquid nitrogen.2. Hematoxylin-eosin (HE) staining and light microscope were used to observe the morphological changes of the retina.3. The expression of VEGF, VEGFR-1and VEGFR-2mRNA were tested with Real time-PCR.4. The influence of signal transduction pathways, proteins expressions of PI3K-Akt and MAPK-ERK1/2, were estimated with Western Blot. Results1. Compared with the normal group, HE staining displayed that the inner limiting membrane were not smooth and lost integrity, the number of endothelial cell was reduced and new blood vessels bud were found in the DM control group. Compared with the DM control group, the inner limiting membrane were more smooth, the number of endothelial cell was increased and new blood vessels bud were no found in the reduced (32-glycoprotein I group and β2-glycoprotein I group.2. The expression of VEGF mRNA in the DM control group is similar with the normal group, VEGFR-1and VEGFR-2mRNA in DM control group is increased (P<0.05). Compared with the DM control group, reduced β2GPI group and P2-glycoprotein I group had increased expression of VEGF mRNA (P<0.05) and decreased expression of VEGFR-1and VEGFR-2. But the expression of VEGF in reduced β2-glycoprotein I group is elevated (P<0.05), compared to P2GPI group, and decreased expression of VEGFR-1and VEGFR-2(P<0.05).3. DM control group had increased expression of p-Akt, p-ERK1/2, compared to DM control group, reduced β2-glycoprotein I and β2-glycoprotein I group had decreased expression of p-Akt and p-ERK1/2(P<0.05). Compared with β2-glycoprotein I group, the expression of p-Akt and p-ERK1/2is decreased in the reduced β2-glycoprotein I group (P<0.05).Conclusion1. The model of type2diabetic rats were successfully established and the rate of establishment of diabetic model were100%.2. Reduce P2GPI and β2GPI can inhibit the retinal neovascularization in a rats model of diabetes.3. Reduce β2-glycoprotein I and P2GPI can downregulates VEFR-1and VEGFR-2, block the phosphorylation of Akt and ERK1/2.