Clinical Significance Of Serum IL-6 And SIL-6R In Patients With Diabetic Nephropathy

Objective: Diabetic nephropathy (DN) is a common and serious microvascular complication of diabetic mellitus and becomes one of disease, which can cause death. The exact mechanism of DN is not clear .In recent years, it is believed that DN results from corporation of several factors, in which associated with mesangial proliferation, infiltrating fibrosis appear to play an important role. With further research, Interleukin-6 (IL-6) and soluble interleukin-6 receptor (sIL-6R) are thought to be important factors in the mechanism of DN. However, at present very little is known of the IL-6,sIL-6R in the patients with all levels of DN. On this basis, we investigated the serum IL-6 and sIL-6R levels in patients with DM complicating macroalbuminuria, microalbuminuria, normal albuminuria and healthy subjects, the levels of systolic blood pressure(SBP ) ,diastolic blood pressure (DBP ), fasting blood glucose (FBG ), hemoglobinA1c (HbA1c ), blood uare nitrogen (BuN ), blood creatinine (Cr ), urinary albumin excretion rate (UAER ), body mass index (BMI ) ,waite hip ratio (WHR ), et al were also measured , furthermore ,compared with those parameters in above groups and the possible correlation in order to studythe significance of them in the pathogenesis of DN,so that we maybe offer some new and useful method in the design of the early diagnostic and therapeutic approaches to threat and prevent the progression in DN.Methods: Sixty-eight patients with DM (1997 ADA diagnostic standards) were selected for this study, 30 male and 38 female, 49.8±11.6 years old. None had present acute or chronic inflammatory disease, DK, collagen disease. Those were divided into three main groups based on urinary albumin excretion rate (UAER ) : ⑴ those with normal albuminuria (UAER < 20μg／min ) were A group,n=17；⑵those with DM complicated microalbuminuria(UARE:20~200μg／min )were B group ,n=24; ⑶those with DM complicated macroalbuminria (UAER > 200μg／min) were C group, n=17. Healthy individuals were used as control group, n=20, 9 male and 11 female, 50.1±10.2 years old, without acute or chronic inflammatory disease, history of liver ,kidney , hypertension or DM disease . The main clinical features such as FBG,PBG ,HbA1c,serum lipid, renal function,UAER,BP and BMI were tested in all subjects. The serum levels of IL-6 and sIL-6R were measured by ELISA method. All these data were expressed as mean±SE, statistical comparisons were done using independent test or one-way analysis were applied when appropriate. All the statistical analysis was dealt with SPSS 10.0 software. Results: 1. The serum level of IL-6 in control group was 1.63±0.36ug/L,in patients of A group ,B group and C group were 1.92±0.49ug/L, 2.43±0.52ug/L and 3.25±0.29ug/L. The serum level of IL-6 in patients of A group ,B group and C group were significantly higher than those in healthy controls (all P<0.01 ) ; Serum level of IL-6 in B group and C group were higher than those in A group (all P<0.05); serum level of IL-6 in C group was higher than in B group (P<0.01). 2. The serum level of sIL-6R in control group was 22.70±3.25ug/L; in patients of A group ,B group and C group were 43.56±21.27ug/L, 44.17±31.21 and 72.47±29.59 ug/L. The serum level of sIL-6R in A, B,and C groups were higher than those in control group (all P<0.01 ); Serum level of sIL-6R in C group was higher than in (P<0.01), but there was no difference in statistical analysis between A and B groups (P>0.05). 3.The serum levels of IL-6 and sIL-6R in all DM patients with hypertension were higher than those in all DM patients without hypertension, but there was no difference between them (all P>0.05). 4. There was a direct correlation between IL-6 and sIL-6R (r=0.328,P<0.01). There was a direct correlation between serum IL-6 and UAER in all diabetic patients (r=0.691,P<0.05). In addition, there was a direct correlation between serum sIL-6R and UAER in all-diabetic patients (r=0.448, P<0.05). 5. In all diabetic patients there was a positive correlation betw...