Effects of TJN-598, a new selective phosphodiesterase type IV inhibitor on anti-Thy1 nephritis in rats.

BACKGROUND: Phosphodiesterase type IV (PDEIV) plays an important role in the immune response and inflammation. However, it is well known that classical PDEIV inhibitors have systemic side effects, so the clinical and chronic use of these agents as therapy for glomerulonephritis is difficult. This study was performed to elucidate the anti-nephritic effects of TJN-598, a new chemical compound derived from herbal components, on experimental mesangial proliferative glomerulonephritis. METHODS: We first examined the effects of TJN-598 and captopril on mesangial expansion induced by anti-Thy1 serum in rats. Second, to investigate the effects of TJN-598 and rolipram, which are typical PDEIV inhibitors, on the production of tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-ß1, glomeruli were isolated from rats with anti-Thy1 nephritis and incubated with the test drugs in vitro for 48 h. RESULTS: Treatment with TJN-598 prevented an increase in the mesangial area/total glomerular area, in the number of cells in the glomerular cross section and matrix index. TJN-598 also inhibited the increases in the expression of α-smooth muscle actin, the TGF-ß1-positive area, in the number of ED-1 positive cells and proliferating cell nuclear antigen-positive cells in the glomeruli. Furthermore, administration of TJN-598 inhibited increases in the levels of TGF-ß1 protein derived from glomeruli with anti-Thy-1 nephritis. The addition of both TJN-598 and rolipram to the culture supernatant inhibited both increased expression of TGF-ß1 and increases in levels of TNF-α in glomeruli isolated from rats with anti-Thy1 nephritis in a dose-dependent manner. CONCLUSION: These results suggest that TJN-598, a PDEIV inhibitor, is effective against expansion of mesangial cells, via the suppression of secretion of TGF-ß1 and TNF-α from inflamed glomeruli.

Effect of TJN-331 on anti-Thy1 nephritis in rats via inhibition of transforming growth factor-ß1 production.

This study was performed to examine the effects of the antifibrotic agents TJN-331 and tranilast on mesangial expansion in a rat model of anti-Thy1 nephritis. We first investigated the effects of TJN-331 and tranilast on mesangial expansion induced by anti-Thy1 serum in rats, and determined the counts of glomerular cells and proliferative cell nuclear antigen (PCNA)-positive cells. The effects of TJN-331 and tranilast on production of transforming growth factor-ß1 (TGF-ß1) by isolated glomeruli incubated for 48 h were then examined. The TGF-ß1 staining score, the number of TGF-ß1-positive cells and the TGF-ß1 receptor-positive area in the anti-Thy1 nephritis model were also measured using immunohistochemistry. TJN-331 administered from day 1 (the day after anti-Thy1 serum injection) blocked an increase in mesangial matrix accumulation on days 4 and 8, compared to untreated anti-Thy1 nephritic rats. TJN-331 also inhibited both the increase in the number of glomerular cells on day 8 and the decrease in this cell count on day 2 observed in untreated nephritic rats, and TJN-331 and tranilast inhibited an increase in PCNA-positive cells in the glomerular cross section on days 4 and 8. Both TJN-331 and tranilast inhibited increases in the TGF-ß1 protein content from nephritic glomeruli, the TGF-ß1-positive area, and the number of TGF-ß1-positive cells/cross section in anti-Thy1 nephritic glomeruli. These results suggest that TJN-331 and tranilast prevent expansion of the mesangial area by suppression of TGF-ß1 secretion from inflamed glomeruli.

(E)-N-[(3,4-dimethoxyphenethyl)]-N-methyl-3-(3-pyridyl)-2-propenamide (TJN-331) inhibits mesangial expansion in experimental IgA nephropathy in ddY mice.

BACKGROUND: TJN-331 is an inhibitor of transforming growth factor ß1 (TGF-ß1) production that has similar structural features to the natural product acteoside. This study was performed to examine the antinephritic effects of TJN-331 in a mouse model of experimental IgA nephropathy. MATERIALS AND METHODS: IgA nephropathy was induced in ddY mice by oral administration of bovine γ globulin, followed by reticuloendothelial blocking by colloidal carbon injection and heminephrectomy. Effects of TJN-331 were examined over oral administration periods from 10 to 15 weeks after the third colloidal carbon injection. Intravenous administration of a TGF-ß1-neutralizing antibody was used to investigate the role of TGF-ß1 in IgA nephropathy. RESULTS: Administration of TJN-331 or captopril prevented elevation of serum creatinine. Histopathological examination after both experimental periods showed that TJN-331 inhibited increases in the mesangial matrix index and the number of nuclei per glomerular cross-section, compared with in untreated ddY mice with IgA nephropathy. TJN-331 prevented increase in glomerular TGF-ß1 staining without affecting IgA. In the in vitro study, TJN-331 prevented total TGF-ß1 production from splenocytes stimulated with concanavalin A. A neutralizing antibody against TGF-ß1 prevented increase in the mesangial matrix index and the number of glomerular cells per cross-sectional area. CONCLUSION: These results suggest that TJN-331 is effective against IgA nephropathy in ddY mice and acts via suppression of TGF-ß1 production in glomeruli.

TJN-331 improves anti-glomerular basement membrane nephritis by inhibiting the production of intraglomerular transforming growth factor-beta1.

Transforming growth factor-beta1 (TGF-beta1) plays an important role in the development of glomerulonephritis. The study of experimental glomerulonephritis in rats was performed to examine the antinephritic effects of TJN-331, a new herbally-derived chemical compound. To clarify the action of TJN-331 ((E)-N-(3,4-dimethoxyphenethyl)-N-methyl-3-(3-pyridyl)-2-propenamide) on TGF-beta1 production, glomeruli were isolated from rats with antiglomerular basement membrane (GBM) nephritis and incubated for 48 h with test drugs in vitro. Next, we examined the effects of TJN-331 on rat anti-GBM nephritis induced by injection with anti-GBM serum. TJN-331 dose-dependently inhibited the increase in total and mature TGF-beta1 production from nephritic glomeruli, although it did not inhibit TGF-beta1 production from normal glomeruli. Administration of TJN-331, at a dose of 2 mg/kg/d, per os (p.o.), prevented proteinuria and increased crescent formation and adhesion of capillary walls to Bowman's capsule. The increases in mature TGF-beta1 protein production and TGF-beta1 staining score in nephritic rats were reversed by TJN-331 treatment. These results suggest that TJN-331 inhibits proteinuria and histopathological changes in glomeruli via suppression of TGF-beta1 production from inflamed glomeruli.

TJN-419 improves dextran sulfate sodium-induced colitis via inhibition of interleukin-12 release.

We investigated the association of interleukin-12 (IL-12) with development of dextran sulfate sodium (DSS)-induced colitis in mice, and examined the effects of TJN-419, a synthetic compound derived from acteoside, on this process. Enhanced IL-12 production in lipopolysaccharide (LPS)-stimulated macrophages was dose-dependently inhibited by addition of TJN-419 to culture medium, and this effect was abolished by pretreatment with PD98059, an inhibitor of extracellular-regulated kinase. We then assessed the effect of TJN-419 or a neutralizing antibody against murine IL-12 in a DSS-induced colitis model in C57 BL/6 mice. Colitis was induced by 5% DSS solution given as drinking water. Treatment with the anti-IL-12 antibody was performed intravenously and TJN-419 was administered orally. We also investigated the effect of TJN-419 on erosion in the rectum in a DSS-induced colitis model in rat. The IL-12 level in the rectum was significantly enhanced and the IL-10 level was significantly decreased in animals with DSS-induced colitis compared with untreated controls. Intravenous injection of the anti-IL-12 antibody and oral administration of TJN-419 inhibited clinical symptoms in DSS-induced colitis. TJN-419 also inhibited the increase in IL-12 and suppressed the area of erosion in the rectum in DSS-induced colitis in rats. These results indicate that IL-12 has a possible role in development of DSS-induced colitis and that TJN-419 is effective for treatment of this disease model via inhibition of IL-12 production.

TJN-259 improves mesangial lesions in experimental immunoglobulin A nephropathy in ddY mice.

TJN-259 is a chemical substance based on the structural features of the botanically derived ingredient acteoside. This study was performed in order to elucidate the antinephritic effects of TJN-259 in experimental immunoglobulin A (IgA) nephropathy. In this study, 28-week-old ddY mice were used as a spontaneous model of IgA nephropathy. With regard to spontaneous IgA nephropathy, we investigated the effects of TJN-259 administered from 28 to 40 weeks. In addition, an accelerated model of IgA nephropathy was experimentally induced in ddY mice by oral administration of bovine serum albumin, followed by reticuloendothelial blocking by colloidal carbon injection and heminephrectomy. At 10 weeks after the 3rd carbon injection, we also examined the effects of TJN-259 on accelerated IgA nephropathy. To investigate the effects of TJN-259 on transforming growth factor (TGF)-beta1 production in accelerated IgA nephropathy, kidneys were isolated and measured TGF-beta1 by the enzyme-linked immunosorbent assay (ELISA) method. The administration of TJN-259 to mice with spontaneous IgA nephropathy decreased the incidence of mesangial expansion as well as the number of nuclei per glomerular cross-section in comparison with that of non-treated mice. In addition, TJN-259 treatment prevented the increase in the incidence of mesangial expansion, crescent formation, and segmental sclerosis in glomeruli in accelerated IgA nephropathy. TJN-259 also inhibited the increased immunostaining score of collagen type IV and TGF-beta1 in glomeruli of accelerated IgA nephropathy. Treatment with TJN-259 inhibited the increases in renal total and mature TGF-beta1 protein levels in accelerated type IgA nephropathy. TJN-259 failed to inhibit the increase in serum IgA levels in both models. These results suggest that TJN-259 was an effective treatment against IgA nephropathy in ddY mice, acting via the suppression of TGF-beta1 production in glomeruli.