The Role Of Erythropoietin In Diabetic Retinopathy

Background: Diabetic Retinopathy(DR)refers to fundus lesions caused by the long-term metabolic changes caused by diabetes,which cause damage to the retinal micro-vessels and cause fundus lesions.It is the most common diabetic complication and the main blinding factor in the working population.Vascular leakage which are caused by increased vascular permeability and vascular proliferation,are the main cause of diabetic retinopathy,especially in late-stage diabetic retinopathy.Abnormal neovascularization in the retina is the main pathological feature of proliferative diabetic retinopathy.Erythropoietin(EPO)is a multifunctional factor whose primary function is to regulate erythropoiesis in the bone marrow.In addition to regulate erythropoiesis,it can also induce vascular proliferation,which has a certain effect on vascular stability and vascular proliferation,and is highly expressed in the diabetic retinopathy eyeball.Therefore,there is controversial whether EPO is a protective factor or a pathogenic factor of diabetic retinopathy.Methods:(1)We checked EPO protein level in PDR and control serum using ELISA to see whether EPO can serve as a correlation factor for DR.(2)We compared vessels percentage area using cell tube formation assay to see whether HRMEC can be a cell model for the study at the role of EPO in DR in vitro.(3)First,We checked the expression of EPOR and CD131 on HRMEC through RT-PCR and WB,and constructed LV-RNAi to silence EPOR and CD131 on HRMEC,then compared vessels percentage area using cell tube formation assay again to see whether EPO regulates angiogenesis in DR through EPOR and CD131.Results:(1)The ELISA has shown that the EPO protein level in serum of patients with diabetic retinopathy was significantly higher than that of diabetic patients without retinopathy and statistical significance was set at a P value of less than 0.05.(2)The cell tube formation shown that the vessels percentage area of HRMEC cells stimulated by 500 ng/ml and 1000 ng/ml EPO protein were 38.66325 and 38.5157,respectively.The angiogenesis effect was significantly higher than that of the control group which was 23.39811.(3)The RT-PCR and WB has shown that EPOR and CD131 were expressed on HRMEC cells;The Q-PCR has shown that lentiviral silencing effectively silenced EPOR and CD131,and the expression levels of EPOR and CD131 in HRMEC cells were halved;The cell tube formation has shown that the angiogenesis of HRMEC cells silencing EPOR and CD131 by lentivirus was significantly lower than that of normal HRMEC cells.Discussion:(1)EPO can serve as a correlation factor for DR.(2)HRMEC can be a cell model for the study at the role of EPO in DR in vitro.(3)EPO may regulate angiogenesis in DR through EPOR and CD131.