Expression And Significance Of EGFl6,EGFl7 In Vitreous And Serum Of Patients With Diabetic Retinopathy

Research BasicsDiabetic retinopathy(DR)is one of the most common complications of diabetes and one of the important causes of vision loss in working-age people worldwide.The main pathological changes of diabetic retinopathy is the micro-circulatory structure and function disorder,changes in capillary cell structure,capillary microaneurysm formation and capillary occlusion.The condition of diabetic retinopathy is complex,and a large number of molecular and biochemical mechanisms are involved.The etiology of diabetic retinopathy has not been fully elucidated.The mechanism of endogenous pathogenic and protective molecules is currently one of the hot research directions for the prevention and treatment of diabetic retinopathy.Epidermal growth factor like domain 6(EGFL6)and epidermal growth factor like domain 7(EGFL7)are hot research molecules in oncology and participate in the formation of tumor neovascularization.Since the formation of new blood vessels is one of the most important pathological changes of diabetic retinopathy,EGFL6 and EGFL7 which cause neovascularization may be related to the development of diabetic retinopathy.EGFL6 is a member of the EGF repeat superfamily and it is highly expressed in embryos and tumor tissues.It also has the function of promoting the proliferation and migration of vascular endothelial cells,suggesting that EGFL6 participates in many important physiology and pathological activity.EGFL6 is a paracrine factor,andstudies have confirmed that it may initiate neovascularization through the ERK pathway and Tie2/PI3K/AKT signaling pathway.EGFL7,also known as endostatin(VE-statin),is a novel vascular endothelial cell-specific secreted protein discovered in recent years and a member of the EGF repeat superfamily.The current study found that EGFL-7 plays an important role in promoting the proliferation,migration,germination,and infiltration of vascular endothelial cells and is associated with the remodeling of extravascular matrices such as tumor blood vessels,inflammatory tissues,and atherosclerotic plaque.The expression of EGFL7 is low in normal mature tissues,and elevated EGFL-7expression may be associated with neovascularization.ObjectiveIn this study,we detected the expression levels of EGFL6,EGFL7,and VEGF in serum and vitreous of patients,and preliminary explored the role of EGFL6 and EGFL7 in diabetic retinopathy,evaluating the significance and clinical practical value of EGFL6 and EGFL7 in the development of diabetic retinopathy.MethodsFrom March 2017 to December 2017,there were 30 patients undergoing 23 G standard triple-channel vitrectomy at the First Ophthalmology Department of the First Affiliated Hospital of Zhengzhou University.Among them,20 patients(20 eyes),10 males and 10 females,with diabetic retinopathy were included as experimental group;10 patients(10 eyes),5 males and 5 females,with rhegmatogenous retinal detachment without history of diabetes were included control group.Record patients' medical history,age,gender,and other clinical data.All patients underwent routine ophthalmology examination,measurement of refractive power.Blood specimens and vitreous specimens of the patients were collected.The expression levels of EGFL6,EGFL7,and VEGF in the serum and vitreous of the patients were measured by enzyme-linked immunosorbent assay(ELISA).Statistical analysis was performed tocompare the expression differences of the samples.Result1.The expression of EGFL6 of vitreous in experimental group was252.32±141.87 pg/ml,and in control group was 72.22±128.22 pg/ml.There was a significant difference between the two groups(P<0.05).2.The expression of EGFL7 and VEGF the two groups of vitreous samples had no significant difference(P>0.05).3.The expression of EGFL6,EGFL7,VEGF in serum in the two groups were not statistically significant(all P> 0.05).Conclusions1.The expression of EGFL6 of vitreous in patients with diabetic retinopathy was higher than that of patients with rhegmatogenous retinal detachment,and the difference was statistically significant.This suggests that intravitreous EGFL6 may be involved in the pathogenesis of diabetic retinopathy and the process of intraocular neovascularization.EGFL6 may become a new indicator for future assessment of diabetic retinopathy and a new target for prevention and treatment.2.The expression of EGFL6 of serum had no significant difference between patients with diabetic retinopathy and patients with rhegmatogenous retinal detachment.3.The expression of EGFL7 of both serum and vitreous have no significant difference between in patients with diabetic retinopathy and rhegmatogenous retinal detachment.This suggests that whether EGFL7 is involved in the pathogenesis of diabetic retinopathy still needs further study.