A pathogenic role for JNK signaling in experimental anti-GBM glomerulonephritis.

Activation of the c-Jun NH2-terminal kinase (JNK) signaling pathway is involved in the immune response; however, little is known of its role in immune-induced renal injury. In this study, we examine JNK signaling in the rat anti-glomerular basement membrane (GBM) disease model using CC-401, a specific JNK inhibitor. Animals were given CC-401, vehicle alone or no treatment starting before anti-GBM serum injection and continued treatment until killing. In acute disease, CC-401 blocked JNK signaling and reduced proteinuria in the first 24 h. The transient neutrophil influx seen at 3 h of disease was not affected, however. Continued CC-401 treatment suppressed glomerular and tubulointerstitial damage usually seen at 14 days. The protective effect may be due to modulation of macrophage activation, as CC-401 had no effect upon glomerular macrophage infiltration at day 14 despite the suppression of glomerular lesions and a marked reduction in renal tumor necrosis factor-alpha and inducible nitric oxide synthase messenger RNA levels. Treatment with CC-401 had no apparent effect on T cell or humoral immune responses. These studies suggest that JNK signaling promotes renal injury in acute and progressive rat anti-GBM disease. JNK inhibitors may be a novel therapeutic approach for the treatment of human glomerulonephritis.

Treatment for lupus nephritis.

BACKGROUND: Lupus nephritis is the renal manifestation of systemic lupus erythematosus (SLE) - a disease mainly affecting young women with substantial morbidity and mortality. It is classified by the World Health Organization (WHO) criteria I - VI based on histology. WHO Class IV is a diffuse proliferative glomerulonephritis which has the worst prognosis without treatment, with a reported 17% five year survival in the era 1953-1969. This survival was 82% in the early 1990's and continues to improve. An important factor behind this has been the use of cytotoxics such as cyclophosphamide in addition to steroids. OBJECTIVES: To assess the benefits and harms of different treatments in biopsy-proven proliferative lupus nephritis (LN). SEARCH STRATEGY: We searched the Cochrane Renal Group's specialised register (January 2003), the Cochrane Central Register of Randomised Controlled Trials (CENTRAL - The Cochrane Library issue 1, 2003), MEDLINE (1966 - 31 January 2003), EMBASE (1980 - 31 January 2003) and handsearched reference lists of retrieved articles. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs comparing treatments for PLN in both adult and paediatric patients with Class III, IV, Vc, Vd lupus nephritis were included. All treatments were considered. DATA COLLECTION AND ANALYSIS: Data was extracted and quality assessed independently by two reviewers, with differences resolved by discussion. Dichotomous outcomes are reported as relative risk (RR) and measurements on continuous scales are reported as weighted mean differences (WMD) with 95% confidence intervals. Subgroup analysis by study quality, drug type and drug route have been performed where possible to explore reasons for heterogeneity. MAIN RESULTS: Of 920 articles identified, 25 were RCTs suitable for inclusion, which enrolled 915 patients. The majority compared cyclophosphamide or azathioprine plus steroids versus steroids alone. Cyclophosphamide plus steroids reduced the risk of doubling of serum creatinine (RR 0.59, 95% CI 0.40 to 0.88) compared to steroids alone but had no impact on mortality (RR 0.98, 95% CI 0.53 to 1.82). The risk of ovarian failure was significantly increased (RR 2.18, 95% CI 1.10 to 4.34). Azathioprine plus steroids reduced the risk of all cause mortality compared to steroids alone (RR 0.60, 95% CI 0.36 to 0.99), but did not alter renal outcomes. Neither therapy was associated with increased risk of major infection. No benefit was found with addition of plasma exchange to cyclophosphamide or azathioprine plus steroids for mortality ( RR 0.71, 95% CI 0.50 to 1.02), doubling of serum creatinine (RR 0.17, 95% CI 0.02 to 1.26) or end-stage renal failure (RR 1.24, 95% CI 0.60 to 2.57). There was also no increased risk of major infection (RR 0.69, 95% CI 0.35 to 1.37). REVIEWER'S CONCLUSIONS: Until future RCTs of newer agents are completed, the current use of cyclophosphamide combined with steroids remains the best option to preserve renal function in proliferative LN. The smallest effective dose and shortest duration of treatment should be used to minimise gonadal toxicity, without compromising efficacy.