Impact of the evaluated plasma homocysteine on T2DM patients with diabetic nephropathy and diabetic retinopathy

Abstract

Objective To investigate the impact of plasma homocysteine （ Hcy） on type 2 diabetics （ T2DM） patients with diabetic nephropathy （ DN） and diabetic retinopathy （ DR） , and to explore the correlation among the levels of plasma Hcy , vascular endothelial growth factor （VEGF）, homeostasis model assessment of insulin resistance （HOMA-IR）, and insulin resistance （ISI）. Methods A total of 241 cases of diabetes was recruited as subjects according to the 2010 China guideline for type 2 diabetes.The history of smoking, hypertension, duration of diabetes, height, and weight were measured.Fasting blood were collected to analyze the levels of fasting insulin （FINS）, fasting plasma glucose （FPG）, glycated hemoglobin a1c （HbA1c）, plasma Hcy （Rate method）, and VEGF [enzyme-linked immunosorbent assay, ELISA）].Results The age, body mass index （BMI）, the history of hyperten-sion, duration of diabetes, HbA1c, homeostasis model assessment of insulin resistance （HOMA-IR）, microalbuminuria （MAU）, and VEGF were positively correlated with the levels of plasma Hcy or VEGF .The levels of ISI were reduced with the increased levels of Hcy or VEGF.The history of smoking was positively correlated with the VEGF .Spearman correlation analysis demonstrated that the levels of plasma Hcy were positively correlated with the levels of VEGF （ r =0.498 , P <0.01 ） .In the groups of diabetic retinopathy and early diabetic nephropathy , it could find that increased duration of diabetes , increased IR, higher levels of HbA1c and VEGF, and the levels of plasma Hcy≥10μmol/L might be the risk factors of DR （ P <0.05 ） .Only the history of hypertension and high levels of VEGF and Hcy in early DN showed a strong correlation （ P <0.05 ） .Conclusions Spearman correlation analysis demonstrated that the levels of plasma Hcy were positively correlated with the levels of VEGF .Higher levels of Hcy and VEGF might be the risk factors of the early DN and DR.At the same time, lower level of ISI might be the risk factor of DR , but the reduction of ISI might not be the main risk factor of the early DN . Key words: Hyperhomocysteinemia; Diabetic retinopathy; Diabetic nephropathies; Insulin resistance; Endothelial growth fac-tors/biosynthesis