The Role Of Asprosin In Diabetic Retinopathy And Its Molecular Mechanism

Objective: In recent years,the role of a new type of adipokine-asprosin(Asp)in diabetes,obesity and other metabolic diseases has been widely concerned.Studies have shown that asprosin plays a key role in carbohydrate metabolism,insulin resistance and microvascular complications.Other studies have shown that the level of serum asprosin in cataract patients with DR is significantly higher than that in cataract control group,which suggests that asprosin may participate in the occurrence and development of DR to a certain extent.Therefore,this project will study the role of asprosin in diabetic retinopathy and preliminarily explore its pathogenesis.Methods: This study was divided into two parts.Part one: In the process of vitreoretinal surgery,vitreous humor samples were collected according to the standard,and the levels of asprosin and related factors were measured and analyzed by enzyme-linked immunosorbent assay(Elisa).The research objects were divided into the following three groups: 1.Control group: 28 cases of idiopathic macular hole;2.PDR group: 30 cases of PDR patients;3.PDR +PRP group: 23 cases of PDR patients who had been treated with PRP more than one month before surgery.The blood routine,biochemical,liver and kidney function of all patients were collected.Part two: This part of the study was to further explore the role of asprosin and its molecular mechanism in human retinal microvascular endothelial cells.Human retinal microvascular endothelial cells were purchased and cultured,and divided into the following six groups: 1.Normal glucose group(5.5 m M);2.High glucose model group(30 m M);3.Normal group-Asp overexpression-control;4.Normal group + Asp overexpression;5.Model group-Asp silencing-control;6.Model group + Asp silencing.Firstly,the expression levels of asprosin were detected by PCR and WB,then cell apoptosis and cell proliferation experiments were carried out.Finally,the expression levels of apoptosis and autophagy related proteins were analyzed.Results: Part one: 1.In terms of age,the control group was significantly different from PDR group and PDR + PRP group(P<0.05).In terms of fasting blood glucose(FBG),the control group was significantly different from PDR group and PDR + PRP group(P<0.05).2.Compared with the control group,the expression levels of asprosin,caspase3 and VEGF in PDR group were significantly increased(P<0.05),but LC3 B was significantly decreased(P<0.05);while compared with PDR group,the expression levels of caspase3 and VEGF in PDR + PRP group were significantly decreased(P<0.05).There were no significant differences in the expression levels of asprosin and LC3B(P>0.05).In PDR group,asprosin and caspase3(r=0.8943,P<0.05),asprosin and VEGF(r=0.8384,P<0.05),caspase3 and LC3B(r=0.7625,P<0.05)were significantly positively correlated,but asprosin and LC3B(r=-0.1418,P>0.05)were not significantly correlated.Part two: Compared with normal glucose group,the activity of human retinal microvascular endothelial cells in high glucose model group decreased significantly and the apoptosis increased(P<0.05).Compared with normal glucose group,the activity of human retinal microvascular endothelial cells in normal group + Asp overexpression decreased significantly and the apoptosis increased(P<0.05).While compared with high glucose model group,the activity of human retinal microvascular endothelial cells in model group + Asp silencing was significantly restored,and the apoptosis was also reduced(P<0.05).2.In human retinal microvascular endothelial cells,the effect of Asp overexpression and silencing was verified by PCR and WB.WB results showed that compared with normal glucose group,the expression levels of asprosin,Bax,caspase3,P53,P62 and VEGF in high glucose model group were increased significantly,Bcl-2,LC3 B and beclin-1 were decreased significantly(P<0.05).Similar results were also found in normal group + Asp overexpression.While compared with high glucose model group,the expression levels of asprosin,Bax,caspase3,P53,P62 and VEGF in model group + Asp silencing were decreased significantly,Bcl-2,LC3 B and beclin-1 were increased significantly(P<0.05).Conclusion: 1.The expression levels of asposin,caspase3 and VEGF in vitreous of PDR patients are significantly increased,while LC3 B is significantly decreased.PRP treatment more than one month before operation can reduce the expression levels of caspase3 and VEGF in vitreous of PDR patients.2.High glucose can significantly increase the expression levels of asprosin,Bax,caspase3,P53,P62 and VEGF,decrease Bcl-2,LC3 B and beclin-1,decrease the cell activity,inhibit autophagy and promote apoptosis in human retinal microvascular endothelial cells.The results of Asp overexpression are similar to those of cells incubated with high glucose.Asp silencing can significantly reverse these changes.The role of asprosin in diabetic retinopathy may be through inhibiting autophagy and promoting apoptosis.