AIM: To observe the changes of serum Adropin protein(AD)and neprilysin(NEP)levels in patients with diabetic retinopathy and to analyse the influencing factors.

METHODS: A total of 167 patients with type 2 diabetes were enrolled in this study. They were divided into simple type 2 diabetes group(DM group)with 59 cases and type 2 diabetic retinopathy group(DR group)with 108 cases. Furthermore, the DR group included patients in two periods of non-proliferation diabetic retinopathy(NPDR group)and proliferative diabetic retinopathy(PDR group). There were 45 patients in NPDR group and 63 patients in PDR group, meanwhile, another 57 healthy subjects were selected as the normal control group(NC group). Measuring the hight and weight and calculating body mass index(BMI). Indices of fasting plasma glucose(FPG), systolic blood pressure(SBP), diastolic blood pressure(DBP), total cholesterol(TC), triacylglycerol(TG), alanine aminotransferase(ALT), aspartate aminotransferase(AST)hemoglobin Alc(HbA1c)were be detected, while levels of serum adropin protein(AD)and neprilysin(NEP)were measured by enzyme-linked immunosorbent assay(ELISA). The correlation between AD, NEP and other indicators was analyzed by Pearson correlation analysis. The independent influence factors of both were analyzed by multiple linear regression.

RESULTS: Compared with the NC group, the AD level in the DM group, NPDR group, and PDR group decreased gradually, with the lowest level in the PDR group(P<0.05). The level of NEP in each group gradually increased, and the highest one was in the PDR group(P<0.05). Multiple linear regression analysis indicated that FPG, HbA1c and NEP were independently correlated with AD. BMI, FPG, HbA1c and AD were independently correlated with NEP.

CONCLUSION: In patients with diabetic retinopathy, AD level would be decreased with the progression of DR, and NEP level would be gradually increased, both of which may be involved in the development of DR.