Premium
Expression of Apoptosis‐related Genes in Chronic Cyclosporine Nephrotoxicity in Mice
Author(s) -
Yang Chul Woo,
Faulkner Gregory R.,
Wahba Ihab M.,
Christianson Tracy A.,
Bagby Grover C.,
Jin Dong Chan,
Abboud Hanna E.,
Andoh Takeshi F.,
Bennett William M.
Publication year - 2002
Publication title -
american journal of transplantation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.89
H-Index - 188
eISSN - 1600-6143
pISSN - 1600-6135
DOI - 10.1034/j.1600-6143.2002.20501.x
Subject(s) - tunel assay , apoptosis , microgram , microbiology and biotechnology , fas ligand , proteases , messenger rna , nephrotoxicity , terminal deoxynucleotidyl transferase , andrology , medicine , endocrinology , kidney , biology , enzyme , gene , biochemistry , programmed cell death , in vitro
To define the mechanism of cyclosporine (CsA)‐induced apoptosis, we investigated the expression of apoptosis‐related genes in experimental chronic CsA nephrotoxicity. Mice on a low‐salt (0.01%) diet were given vehicle (VH, olive oil, 1 mg/kg/day), or CsA (30 mg/kg/day), and sacrificed at 1 and 4 weeks. Apoptosis was detected with deoxynucleotidyl transferase‐mediated dUTP nick end‐labeling (TUNEL) stain, and the expressions of apoptosis‐related genes were evaluated by reverse transcription‐polymerase chain reaction, immunoblot or immunohistochemistry. The activity of caspase 1 and 3 was also evaluated. The CsA group showed increases in apoptotic cells compared with the VH group (54 ± 41 vs. 3 ± 3, p < 0.05), and the number of apoptotic cells correlated well with interstitial fibrosis scores (r = 0.83, p < 0.01). The CsA group showed a significant increase in Fas‐ligand mRNA (0.20 vs. 0.02 amol/μg total RNA, p < 0.05) and Fas protein expression (146% vs. 95%, p < 0.05), compared with the VH group. The CsA group showed significant increases in ICE mRNA (0.21 vs. 0.03 amol/μg total RNA at 4 weeks, p < 0.05) and CPP32 mRNA (0.18 vs. 0.03 amol/μg total RNA at 4 weeks, p < 0.05), compared with the VH group. The enzymatic activity of ICE (16.6 vs. 7.9 ρmol/μg/ h, p < 0.05) and CPP32 protease (15.6 vs. 2.7 ρmol/μg/ h, p < 0.05) proteases were increased in the CsA group, compared with the VH group. The ratio between bax and bcl‐2 protein increased significantly in the CsA group (5.3‐fold), compared with the VH group. Levels of p53 protein also increased in the CsA group. Immunohistochemical detection of Fas, Fas‐ligand, ICE and CPP32 revealed strong immunoreactivity in renal tubular cells in areas of structural injury. These findings suggest that local activation of the apoptosis‐related genes is associated with CsA‐induced apoptotic cell death.