The Changes Of Serum And Urinary Levels Of Insulin-like Growth Factor-1 And Their Clinical Significance In Type 2 Diabetics With Diabetic Nephropathy

Objective To study the clinical significance of serum and urinary insulin-like growth factor-1 (IGF-1) in type 2 diabetics with diabetic nephropathy.Methods Serum and urinary IGF-1 were measured by immunoradiometry. Urinary albumin excretion rates was measured by radioimm unoassay. Urine retinal-binding protein(RBP)was measured by ELISA. Eighty patients with type 2 diabetic mellitus (DM) were divivded into early DN group (n=28 cases, microalbuminuria,UAER20-200μg/min), clinical DN group (n=20 cases, macroalbuminuria.UAER>200μg/min)and DM group(n = 32 cases,normoalbuminuria, UAER<20μg/min). Twenty healthy people were as controls. Results Serum IGF-1 in DM group (n=32 cases, normoalbuminuria) was significantly lower than that in controls (n=20 cases ) . (t=2.09,P<0.01). In contrast, urinary IGF-1 level in DM group (n=32 cases , normoalbuminuria ) did not differ from that in controls (n=20 cases).(t=0.860,P>0.05).Urinary IGF-1 level in the group of early DN (n=28 cases, microalbuminuria)was significantly higher than that in the group of DM (t=3.18,p<0.01). Urinary IGF-1 level in the group of clinical DN (n=20 cases, macroalbuminuria)was not significantly different from that in the group of early DN (t=0.846,p>0.05) .Serum IGF-1 level in the group of early DN was not significantly different from that in the group of DM (t=0.853,p>0.05).Serum IGF-1 level in the group of clinical DN was not also significantly different from that in the group of early DN (t=1.292,p>0.05). Urinary IGF-1 level was positively correlated with UAER(r=0.519,p<0.01). Urinary IGF-1 level was also positively correlated with RBP(r=0.884,P<0.01). It was not showed that urinary IGF-1 level was significantly correlated with serum IGF-1 level, FBG, HbA1c, SBP, DBP and serum creatinine...