Background: Growing evidence suggests that blockade of the aldosterone-receptor may preserve kidney function by anti-inflammatory effects independent of the blood pressure. We hypothesized that the selective aldosterone-receptor antagonist eplerenone has a profound anti-inflammatory effect in the autologous phase of anti-glomerular basement membrane (GBM) glomerulonephritis (GN).
Methods: Mice received ≈200mg/kg body wt/day eplerenone via supplemented chow diet or standard chow starting at the day of immunization with rabbit IgG. Three days later the anti-GBM antibody was injected and the experiments were stopped at day 7 and 14.
Results: Mice receiving eplerenone showed significantly decreased albuminuria and glomerular sclerosis at day 7 and 14 after induction of anti-GBM GN. Eplerenone treatment significantly inhibited the infiltration of CD4+, CD8+ T cells and macrophages into the kidneys. Circulating levels and glomerular deposition of autologous IgG were comparable in both groups. At day 7 the pro-inflammatory cytokines MCP-1 and IL-6 were found to be significantly decreased in regional draining lymph nodes of eplerenone-treated mice, whereas the anti-inflammatory cytokine IL-10 was significantly upregulated. In line, splenocytes from eplerenone-treated nephritic mice produced significantly increased IL-10.
Conclusion: Aldosterone-receptor blockade by eplerenone effectively attenuated proteinuria, kidney damage and the inflammatory response in anti-GBM GN by significantly decreasing pro-inflammatory cytokines in the regional draining lymph nodes of the kidney. Our results suggest that this selective aldosterone receptor antagonist is a possible additional tool in the treatment of GN.
Keywords: Aldosterone antagonism; eplerenone; glomerulonephritis; renal inflammation.