TY - JOUR
T1 - Effect of nitric oxide modulation on TGF-β1 and matrix proteins in chronic cyclosporine nephrotoxicity
AU - Shihab, Fuad S.
AU - Yi, Hong
AU - Bennett, William M.
AU - Andoh, Takeshi F.
N1 - Funding Information:
This work was supported in part by grants from the Dialysis Research Foundation (F.S.S.) and grants from the Kidney Care Foundation in Jackson, Mississippi, USA (W.M.B. and T.F.A.). Part of this work was presented at the Annual Meeting of the American Society of Nephrology, Miami Beach, FL, USA, in November 1999.
PY - 2000
Y1 - 2000
N2 - Background. Chronic cyclosporine (CsA) nephrotoxicity is characterized by interstitial fibrosis and afferent arteriolar hyalinosis. L-arginine (L-Arg), the substrate for nitric oxide (NO) synthase and N-nitro-L-arginine-methyl ester (L-NAME), the NO synthase inhibitor, were shown to modulate acute CsA nephrotoxicity. However, the mechanism of fibrosis in chronic CsA nephrotoxicity remains unclear. Thus, we examined the effect of NO modulation on fibrosis and the expression of transforming growth factor-β1 (TGF-β1) and matrix proteins in chronic CsA nephrotoxicity. Methods. Rats were administered CsA (7.5 mg/kg), CsA + L-Arg (1.7 g/kg), CsA + L-NAME (3.5 mg/kg), vehicle (VH), VH + L-Arg, and VH + L-NAME, and were sacrificed at 7 or 28 days. NO production, physiologic parameters, and histology were studied in addition to the mRNA expression of TGF-β1, plasminogen activator inhibitor-1 (PAI-1) and the matrix proteins biglycan and collagens type I and IV by Northern and the protein expression of PAI-1 and fibronectin by enzyme-linked immunosorbent assay. Results. While L-NAME strikingly reduced NO biosynthesis and worsened the glomerular filtration rate and CsA-induced fibrosis, L-Arg had the opposite beneficial effect. In addition, the CsA-induced up-regulated expression of TGF-β1, PAI-1, and the matrix proteins biglycan, fibronectin, and collagen I was significantly increased with L-NAME and strikingly improved with L-Arg. Collagen IV expression was not affected. Also, NO modulation did not affect VH-treated rats. Conclusions. Chronic CsA nephrotoxicity can be aggravated by NO blockade and ameliorated by NO enhancement, suggesting that NO maintains a protective function. NO modulation was associated with a change in TGF-β1 expression, which, in turn, was associated with alterations in matrix deposition and matrix degradation through its effect on PAI-1.
AB - Background. Chronic cyclosporine (CsA) nephrotoxicity is characterized by interstitial fibrosis and afferent arteriolar hyalinosis. L-arginine (L-Arg), the substrate for nitric oxide (NO) synthase and N-nitro-L-arginine-methyl ester (L-NAME), the NO synthase inhibitor, were shown to modulate acute CsA nephrotoxicity. However, the mechanism of fibrosis in chronic CsA nephrotoxicity remains unclear. Thus, we examined the effect of NO modulation on fibrosis and the expression of transforming growth factor-β1 (TGF-β1) and matrix proteins in chronic CsA nephrotoxicity. Methods. Rats were administered CsA (7.5 mg/kg), CsA + L-Arg (1.7 g/kg), CsA + L-NAME (3.5 mg/kg), vehicle (VH), VH + L-Arg, and VH + L-NAME, and were sacrificed at 7 or 28 days. NO production, physiologic parameters, and histology were studied in addition to the mRNA expression of TGF-β1, plasminogen activator inhibitor-1 (PAI-1) and the matrix proteins biglycan and collagens type I and IV by Northern and the protein expression of PAI-1 and fibronectin by enzyme-linked immunosorbent assay. Results. While L-NAME strikingly reduced NO biosynthesis and worsened the glomerular filtration rate and CsA-induced fibrosis, L-Arg had the opposite beneficial effect. In addition, the CsA-induced up-regulated expression of TGF-β1, PAI-1, and the matrix proteins biglycan, fibronectin, and collagen I was significantly increased with L-NAME and strikingly improved with L-Arg. Collagen IV expression was not affected. Also, NO modulation did not affect VH-treated rats. Conclusions. Chronic CsA nephrotoxicity can be aggravated by NO blockade and ameliorated by NO enhancement, suggesting that NO maintains a protective function. NO modulation was associated with a change in TGF-β1 expression, which, in turn, was associated with alterations in matrix deposition and matrix degradation through its effect on PAI-1.
KW - Afferent arteriolar hyalinosis
KW - Collagen
KW - Extracellular matrix
KW - Fibrosis
KW - Glycoprotein
KW - L-arginine
KW - Plasminogen activator inhibitor-1
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U2 - 10.1046/j.1523-1755.2000.00273.x
DO - 10.1046/j.1523-1755.2000.00273.x
M3 - Article
C2 - 10972680
AN - SCOPUS:0033856295
SN - 0085-2538
VL - 58
SP - 1174
EP - 1185
JO - Kidney International
JF - Kidney International
IS - 3
ER -