TY - JOUR

T1 - Different effect of cyclosporine A and mycophenolate mofetil on passive heymann nephritis in the rat

AU - Blume, Cornelia

AU - Heise, Gunhild

AU - Hess, Alexandra

AU - Waldner, Christoph

AU - Grabensee, Bernd

AU - Schroer, Karsten

AU - Heering, Peter

PY - 2005/6

Y1 - 2005/6

N2 - Background: While cyclosporine A (CsA) is an effective therapy for nephrotic syndrome, it has nephrotoxic side effects. We compared the anti-proteinuric effects and nephrotoxicity in rats with passive Heymann nephritis (PHN) of CsA and mycophenolate mofetil (MMF). Methods: PHN was induced in female Wistar rats. Two treatment groups consisting of 8 rats each received either 25 mg of CsA or 25 mg of MMF/kg body weight/day and were compared with untreated controls. Kidney function and proteinuria were monitored over 4 weeks. Western blots were used for densitometric analysis of renal cyclooxygenase-2 (COX-2) protein expression. Thromboxane B2 (TxB2) and 6-keto-PGF1α were determined by radioimmunoassays (RIAs) in renal tissue and urine. Results: Rats with PHN exhibited a marked proteinuria of 12.76 ± 4.42 vs. 0.73 ± 0.28 mg/24 h (p < 0.01) and showed increased glomerular concentrations of TxB2 and 6-keto-PGF1α (992.6 ± 216.9 and 1,187.0 ± 54.2 pg/ mg protein, respectively) compared with healthy controls (595 ± 196.17 and 729 ± 297.84, respectively) and a strongly induced COX-2 protein expression. CsA and MMF treatment reduced PHN-related proteinuria to 2.10 ± 1.47 and 1.47 ± 7.2 mg/24 h, respectively. In rats with PHN, CsA induced a significant deterioration of renal function and enhanced urine excretion of thromboxane A2, paralleled by a significant, twofold increase in COX-2 protein expression and renal prostaglandins. By contrast, MMF treatment in rats with PHN was not nephrotoxic and had no effect on prostaglandin production. COX-2 protein expression under MMF was suppressed. Conclusion: While the antiproteinuric efficacy of MMF and CsA in PHN was comparable, the absence of nephrotoxicity might favor MMF in the treatment of nephrotic syndrome. The CsA-induced increase in COX-2 expression and COX-2-dependent prostacyclin may indicate a mechanism that compensates nephrotoxicity in the diseased and CsA-exposed kidney.

AB - Background: While cyclosporine A (CsA) is an effective therapy for nephrotic syndrome, it has nephrotoxic side effects. We compared the anti-proteinuric effects and nephrotoxicity in rats with passive Heymann nephritis (PHN) of CsA and mycophenolate mofetil (MMF). Methods: PHN was induced in female Wistar rats. Two treatment groups consisting of 8 rats each received either 25 mg of CsA or 25 mg of MMF/kg body weight/day and were compared with untreated controls. Kidney function and proteinuria were monitored over 4 weeks. Western blots were used for densitometric analysis of renal cyclooxygenase-2 (COX-2) protein expression. Thromboxane B2 (TxB2) and 6-keto-PGF1α were determined by radioimmunoassays (RIAs) in renal tissue and urine. Results: Rats with PHN exhibited a marked proteinuria of 12.76 ± 4.42 vs. 0.73 ± 0.28 mg/24 h (p < 0.01) and showed increased glomerular concentrations of TxB2 and 6-keto-PGF1α (992.6 ± 216.9 and 1,187.0 ± 54.2 pg/ mg protein, respectively) compared with healthy controls (595 ± 196.17 and 729 ± 297.84, respectively) and a strongly induced COX-2 protein expression. CsA and MMF treatment reduced PHN-related proteinuria to 2.10 ± 1.47 and 1.47 ± 7.2 mg/24 h, respectively. In rats with PHN, CsA induced a significant deterioration of renal function and enhanced urine excretion of thromboxane A2, paralleled by a significant, twofold increase in COX-2 protein expression and renal prostaglandins. By contrast, MMF treatment in rats with PHN was not nephrotoxic and had no effect on prostaglandin production. COX-2 protein expression under MMF was suppressed. Conclusion: While the antiproteinuric efficacy of MMF and CsA in PHN was comparable, the absence of nephrotoxicity might favor MMF in the treatment of nephrotic syndrome. The CsA-induced increase in COX-2 expression and COX-2-dependent prostacyclin may indicate a mechanism that compensates nephrotoxicity in the diseased and CsA-exposed kidney.

KW - Cyclooxygenase-2

KW - Cyclosporine

KW - Immunosuppressants

KW - Kidney

KW - Mycophenolate mofetil

KW - Passive Heymann nephritis

KW - Prostacyclin

KW - Proteinuria

KW - Thromboxane A

UR - http://www.scopus.com/inward/record.url?scp=20944444129&partnerID=8YFLogxK

U2 - 10.1159/000085029

DO - 10.1159/000085029

M3 - Article

C2 - 15855806

AN - SCOPUS:20944444129

VL - 100

SP - e104-e112

JO - Nephron - Experimental Nephrology

JF - Nephron - Experimental Nephrology

SN - 1660-2129

IS - 2

ER -