Multi-glycoside of Tripterygium wilfordii Hook. f. reduces proteinuria through improving podocyte slit diaphragm dysfunction in anti-Thy1.1 glomerulonephritis.

ETHNOPHARMACOLOGICAL RELEVANCE: Multi-glycoside of Tripterygium wilfordii Hook. f. (GTW) has been proved clinically effective in reducing proteinuria in chronic kidney disease in China. However, the mechanisms involved are still unclear. In this study we examined the effects of GTW at the different dosages on proteinuria and podocyte slit diaphragm (SD) dysfunction in anti-Thy1.1 glomerulonephritis (GN). MATERIALS AND METHODS: Rats with anti-Thy1.1 GN were divided into 2 groups, a GTW group and a vehicle group, and sacrificed at 30 min, on day 7, and on day 14 in Experiments 1, 2 and 3, respectively. The administration of GTW at the moderate and high doses was started 3 days before or at the same time of antibody injection till sacrifice. Proteinuria was determined in Experiments 1, 2, and 3. After sacrifice, the staining intensity of SD-associated key functional molecules including nephrin and podocin, podocyte structure, mesangial change, macrophage infiltration, and blood biochemical parameters were examined, respectively. Protein and mRNA expressions of nephrin and podocin in glomeruli were also investigated. Besides, liver histological characteristics were analyzed. RESULTS: In Experiment 1, GTW pretreatment at the medium dose (75 mg/kg body weight) caused no influence on the induction of anti-Thy1.1 GN and the basal nephrin expression. In Experiment 2, the high dosage (100mg/kg body weight) of GTW ameliorated proteinuria, the distribution of nephrin and podocin, mesangial proliferation, and the activated macrophage accumulation, as compared with vehicle group (P<0.05). Additionally, it increased mRNA and protein expressions of nephrin and podocin in glomeruli on day 7, but had no influence on podocyte structure. In Experiment 3, the medium dosage (75 mg/kg body weight) of GTW improved proteinuria, the partial matrix expansion, and the distribution of nephrin and podocin on day 14, as compared with anti-Thy1.1 GN rats (P<0.05). GTW at the high or moderate dose did not affect hepatic function on day 7 and on day 14. CONCLUSIONS: Podocyte SD dysfunction, such as the disordered distribution and down-regulation of nephrin and podocin expression, is critically involved in the pathogenesis of anti-Thy1.1 GN induced by mAb 1-22-3. The restoration of the distribution and expression of nephrin and podocin by GTW could be an important mechanism by which GTW ameliorates proteinuria and podocyte SD dysfunction.

Selective CCR2-targeted macrophage depletion ameliorates experimental mesangioproliferative glomerulonephritis.

The CCL2/CCR2 chemokine/receptor axis directs the chemotaxis of infiltrating monocytes/macrophages and T cells and plays a pivotal role in tissue damage and fibrosis in kidney diseases. The eradication of the activated leucocytes should diminish the production of inflammatory mediators, limit tissue damage and ameliorate disease. A recombinant fusion protein (OPL-CCL2-LPM) comprised of the human CCL2 (monocyte chemoattractant protein-1) chemokine fused to a truncated form of the enzymatically active A1 domain of Shigella dysenteriae holotoxin (SA1) has been developed. The CCL2 portion binds specifically to CCR2-bearing leucocytes and the fusion protein enters the cells, where the SA1 moiety inhibits protein synthesis resulting in cell death. The compound was tested in a model of anti-thymocyte serum (ATS)-induced mesangioproliferative glomerulonephritis (ATS-GN). Male rats were injected with ATS on day 0 and treated intravenously with vehicle, 50 or 100 microg/kg of OPL-CCL2-LPM Q2D from days 2, 4, 6 and 8. Urine and blood were collected on days 0, 5 and 9. Animals were sacrificed on day 9. No treatment-related effects on body weight or signs of clinical toxicity were observed. Urine protein levels were decreased in treated animals. At the highest dose, histopathological analyses of kidney sections revealed maximum reductions of 36, 31, 30 and 24% for macrophage count, glomerular lesions, alpha-smooth muscle actin and fibronectin respectively. These results indicate a significant protective effect of OPL-CCL2-LPM in this model of nephritis.

[Effects of multi-glycoside of Tripterygium wilfordii Hook. f. on proteinuria and expression of slit diaphragm-associated molecules in rats with anti-thy1.1 glomerulonephritis].

OBJECTIVE: To examine the effect of multi-glycoside of Tripterygium wilfordii Hook. f. (GTW) on proteinuria and expression of slit diaphragm-associated molecules such as nephrin and podocin in glomerulonephritis induced by anti-Thy1.1 antibody (anti-Thy1 . 1 GN). METHODS: Anti-Thy1.1 GN was induced in rats by a single intravenous injection with 500 microg of anti-Thy1.1 mAb 1-22-3. Fourteen rats were randomly divided into 2 groups, the GTW-treated group and vehicle treated group, and sacrificed on day 14 in Experiment 1 or on day 7 in Experiment 2 after induction of Anti-Thy1.1 GN. Daily oral administration of GTW and vehicle as a control was started from 3 days before injection or at the same time of injection to the day of sacrifice in Experiment 1 or 2. Proteinuria was determined during 14 days in Experiment 1 or during 7 days in Experiment 2. From kidneys taken at sacrifice, glomerular morphological changes, glomerular macrophage infiltration, glomerular expression of nephrin and podocin, and its mRNA expression in renal tissue were examined. RESULTS: In Experiment 1, proteinuria and mesangial matrix expansion were significantly attenuated by GTW treatment. No difference in staining intensity of nephrin and podocin in glomeruli was observed between GTW treated group and vehicle treated group on day 14. In Experiment 2, GTW treatment significantly ameliorated proteinuria, mesangial injury and activated macrophage infiltration in glomerulus. In addition, it significantly increased the expression of nephrin and podocin and its mRNA expression in glomeruli on day 7. CONCLUSION: In anti-Thy1.1 GN, the reduced expression of nephrin and podocin may contribute to the development of mesangial injury and proteinuria. The findings suggest that GTW ameliorates not only proteinuria but also mesangial lesions in anti-Thy1 . 1 GN most likely by increasing the expression of nephrin and podocin.

Multi-glycoside of Tripterygium wilfordii Hook f. ameliorates proteinuria and acute mesangial injury induced by anti-Thy1.1 monoclonal antibody.

BACKGROUND/AIMS: Multi-glycoside from Tripterygium wilfordii Hook f. (GTW) is used for various immune and inflammatory diseases including renal diseases represented by mesangial proliferative glomerulonephritis (MsPGN) in China. However, there have been no fundamental studies on the operating mechanism of GTW on MsPGN. The aim of this study is to examine as the first step the effects of GTW on acute injurious process such as mesangial injury and proteinuria in an acute and reversible Thy.1.1 glomerulonephritis (Thy1.1GN) model and then to clarify the action mechanism of GTW at molecular level by examining its effects on various injurious factors in this model. METHODS: Thy1.1 GN was induced in rats by a single intravenous injection with 500 microg of anti-Thy1.1 mAb 1-22-3. Daily oral administration of GTW and vehicle as a control was started from 3 days before injection of mAb to the day of sacrifice in each experiment. Fourteen rats were randomly divided into 2 groups, GTW-treated and vehicle-treated groups, and sacrificed on day 14 in experiment 1 or on day 7 in experiment 2 after induction of Thy1.1 GN. Proteinuria was determined on days 1, 3, 5, 7, 10 and 14 in experiment 1 or on 1, 3, 5 and 7 in experiment 2. From blood and kidneys taken at sacrifice, blood biochemical parameters, mesangial morphological changes, glomerular macrophage infiltration, and glomerular mRNA expression of cytokines were examined. RESULTS: In experiment 1, proteinuria and mesangial matrix expansion were significantly attenuated by GTW treatment. In experiment 2, GTW treatment significantly ameliorated proteinuria, mesangial lesions and macrophage accumulation in glomerulus. In addition, it significantly reduced the glomerular expression of mRNA for PDGF, MCP-1 and IL-2. CONCLUSION: GTW ameliorated not only proteinuria but also mesangial alterations in Thy1.1 GN most likely by reducing expression of injurious cytokines, indicating that GTW has suppressive effects on acute inflammatory changes in glomeruli.

[Pathogenic factor (Dampness-heat) of glomerulopathy].

Mesangial proliferative glomerulonephritis (MsPGN) induced by chronic serum sickness in rabbits coincide with the human chronic progressive glomerulonephritis resulted from repeated infection, which is similar to pathologic changes of Dampness-Heat Syndrome. The experimental model of MsPGN was treated by Abelmoschus manihot. which could remove the Dampness-Heat. The amount of proteinuria in treating and control group were 62.68mg/24hr and 121.94mg/24hr respectively (P < 0.05), the number of cells in glomeruli were 61.54 and 80.39 respectively (P < 0.01), and diameters of glomeruli were 102.43 microns and 121.13 microns respectively (P < 0.01). It suggested that the drug could alleviate circulating immune complex (CIC) mediated renal injury.