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Background and purpose of diabetic nephropathy (DN) is one of the major chronic complications of diabetes, its early manifestation of renal hypertrophy, glomerular filtration, thickening of the glomerular basement membrane, and thus the development of extracellular matrix accumulation, renal ball hardening renal failure. Due to end-stage renal disease (ESRD) in developed countries, diabetes has become the first cause of renal failure, our upward trend. DN pathogenesis studies focused on glucose and lipid metabolism disorders, hemodynamic abnormalities, the role of inflammatory mediators in recent years in the pathogenesis of DN drawing attention. Infiltration of inflammatory cells and intrinsic renal cells secrete large amounts of pro-inflammatory cytokines, chemokines and various adhesion factor, these factors through autocrine and paracrine the expanding inflammatory effects, eventually leading to kidney dysfunction. IL-18 is found in 1995 with a variety of biological activity of the cytokine, can contribute to the IL-8, TNF-α, IL-1β, the secretion of the ICAM-1, etc. These factors can be affect the IL-18 generated, thereby forming the inflammatory cascade. In recent years, IL-18's role in the pathogenesis of DN attentions. On IL-18 in DN progression of kidney tissue expression changes and there are few studies with other cytokines, domestic been reported. TNF-α is an important component of the cytokine network members, mainly by mononuclear macrophages produce a variety of cells, including endothelial cells and kidney mesangial cells, proximal tubule epithelial cells can produce TNF -α, participate in the pathogenesis of the DN. ICAM-1 as one of the important adhesion molecule, are stimulated expression in vascular endothelial cells, and the Department of the membrane cells and other cell surface enhanced leukocyte adhesion and wear wall, the release of more inflammatory cytokines, kidney disease cell infiltration and proliferation, one of the molecular basis for the expansion of the extracellular matrix and glomerulosclerosis. Nuclear transcription factor-kappaB (NF-κB) cells in a multi-directional regulation of nuclear transcription factors play an important role in the induction of cell signaling and gene expression process, a complex inflammatory response cytokine network NF-κB activation may be a central element, and regulates the interaction between the many cytokines play an important role in the occurrence and development of DN. Immunosuppressant mycophenolate mofetil (MMF) as a novel, efficient, and has been widely used in the prevention and treatment of transplant rejection. In recent years, with the in-depth study of the pharmacological effects of MMF in non-transplanted kidney disease increasing attention vitro experiments found that MMF inhibits macrophage and mesangial cell proliferation and cytokine production. Based on the above theory, the study of streptozotocin (streptozotozin, STZ)-induced diabetic rats, observed a different course of rat glomerular IL-18, TNF-α, ICAM-1 expression and relationship to further understanding kidney inflammation of damage process, to investigate cytokine network systems diabetic nephropathy development. And application of the NF-κB inhibitor pyrrolidine dithiocarbamate (Pyrrolidine dithiocarbamate PDTC) joint of MMF observation of glomerular IL-18, TNF-α, ICAM-1 expression to explore their diabetes The rat kidney synergistic protective effect and mechanism, to provide new ideas, new methods for the treatment of diabetic nephropathy. Research Methods 70 SD rats were fasted for 12h, randomly select 58 single intraperitoneal injection of freshly prepared streptozotocin (STZ) 60mg.kg -1 remaining 12 intraperitoneal injection of considerable The volume of citrate buffer. 72h after glucose ≥ 16.7 mmol.L -1 of the rats diabetic rats, randomly divided into D, P, M, PM group (D group for diabetic untreated group, P group PDTC treatment group, M group MMF treatment group, PM Group for PDTC United MMF treatment group), with normal blood glucose after intraperitoneal injection of citrate buffer 72h rats as normal control group (C group). To give PDTC100mg.kg -1 or (and) MMF10mg.kg -1 orally (dissolved in sterile distilled water), C, and D corresponding group given a considerable volume sterile distilled water, once a day. 4 weeks in each group were randomly Half of the animals were killed and the remaining animals were killed in the weekend of August. Prior to sacrifice, the rats were placed in metal metabolism cages, specimens from the 24-hour urine urine protein; separation of the serum under test blood glucose (BG), blood urea nitrogen (BUN), creatinine (Scr); animals were sacrificed after anesthesia blood was collected from the abdominal vein adding that kidney weight, calculate the kidney weight index (KI); pathological changes of light and electron microscopy kidney; Immunohistochemical detection of glomerular interleukin -18 (IL-18), tumor necrosis factor-α (TNF-α) intercellular adhesion molecule -1 (ICAM-1) expression analysis of the three expression correlation between its expression intensity and 24hUPro, BUN, Scr related. Results 1. Biochemical indicators: four weeks compared with the C group D group and the treatment group, blood glucose, kidney weight index, 24-hour urine protein, serum creatinine increased (P <0.05), weight loss (P <0.05), and urea nitrogen significant difference; addition to the PM group of 24-hour urine protein less than Group D (P <0.05) between each treatment group and D group, no significant difference; no significant difference (P> 0.05) between the P and M group and the PM group. 8 weeks D group and the treatment group, blood glucose, kidney weight index, 24-hour urine protein, blood urea nitrogen, serum creatinine higher than group C (P <0.05) and weighing less than group C (P <0.05); each treatment group, blood sugar Group D was no significant difference (P> 0.05), weight higher than that of group D (P <0.05), kidney weight index, 24-hour urine protein, blood urea nitrogen, serum creatinine less than group D (P <0.05); PM group weight below the P and M group (P <0.05) higher than P, M group (P <0.05), a 24-hour urine protein. Kidney weight index of eight weeks of group D, 24-hour urine protein, blood urea nitrogen, serum creatinine greater than 4 weeks in group D (P <0.05). 2. The immunohistochemistry: 4 weeks of IL-18, TNF-α, the expression of ICAM-1 expression in the D group and the treatment group compared with the C group increased (P <0.05) between each treatment group and D group no significant difference (P> 0.05), no significant difference (P> 0.05) between P, M group and the PM group. 8 weeks, IL-18, TNF-α, ICAM-1 expression in the group D than in group C increased (P <0.05); each treatment group than in the group D decreased expression (P <0.05), but still higher than in group C ( P <0.05); the PM group IL-18, TNF-α, ICAM-1 expression compared with P group decreased (P <0.05), IL-18, TNF-α expression than the M group decreased (P <0.05), ICAM-1 reduce not yet reached a significant difference (P> 0.05), but there is a downward trend. Eight weeks of group D of IL-18, TNF-α, ICAM-1 expression was significantly higher than four weeks in group D (P <0.05). 3. Correlation Analysis: IL-18, TNF-α, ICAM-1 glomerular positive average integral optical density and 24-hour urinary protein, blood urea nitrogen, serum creatinine was positively correlated (P <0.05); IL-18, TNF- positive correlation was also found between the average integrated optical density α, ICAM-1 the glomerulus positive area (P <0.05). 4. Pathological changes: HE staining in group C were normal glomerular structure. Glomerular volume increased in the group D 4 weeks, lobulated, increased mesangial cells and mesangial matrix. 8 weeks, the glomerular volume increases further, the cells were further increased in the ball. Electron microscope to see clear structure of group C rat glomerular capillary endothelial cells, see irregular fenestrae, the basement membrane thickness uniformity, no thickening balloon visceral epithelial cell surface out of many thin and long foot processes maintain a certain distance between the foot processes posts attached to the outside of the basement membrane. Group D basement membrane thickening, uneven thickness, some areas were focal thickening swollen podocytes projections, shorter, and visible foot process fusion, aggravated with the disease increases. Each treatment group, pathological changes in the range between Group C and Group D, the to alleviate most obvious in the PM group. Conclusion 1. High blood sugar lead to the the rat glomeruli IL-18, TNF-α, ICAM-1 expression increased. 2. IL-18, TNF-α, ICAM-1 in diabetic nephropathy development process play an important role. 3. PDTC and MMF kidney of diabetic rats has protective role and is not achieved through the regulation of glucose metabolism, may in part by down-regulating IL-18, TNF-α, ICAM-1 expression, to delay the progression of diabetic nephropathy. 4. Both associated with higher than single-agent able earlier to reduce urinary protein excretion and improve renal pathology, inhibition of IL-18, TNF-α, ICAM-1 expression in a synergistic protective effect on the kidney of diabetic rats for diabetes early prevention of kidney disease provides a new way of thinking.
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