Apoptosis and caspase-3 in experimental anti-glomerular basement membrane nephritis.
The caspase family is central to the proteolytic events of apoptosis. In particular, caspase-3 plays a key role in the execution of apoptosis. However, the importance of caspase-3 in renal cell apoptosis during kidney scarring has not been established. Here, nephrotoxic nephritis (NTN) was induced in Wistar Kyoto rats by a single intravenous injection of rabbit anti-rat glomerular basement membrane serum, with analysis at days 7, 15, 30, and 45 after injection. Cell apoptosis (in situ end labeling of DNA, light and electron microscopy), proliferation (proliferating cell nuclear antigen-positive cells), and inflammation (ED1-positive cells) all increased in NTN kidneys, peaking early (day 7) in the glomeruli and later (days 30 to 45) in the tubules and interstititum. The expression of caspase-3 mRNA (Northern blotting) was increased in NTN kidneys on days 7, 30, and 45 (173.3%, 228%, and 241.7%, respectively; P< 0.05). Western blotting showed that a 24-kD protein band (caspase-3 active subunit) increased with time in NTN kidneys (P < 0.01) and reached a maximum on day 45 (6.08-fold increase). A 32 kD band (caspase-3 precursor) was also increased on day 45 (3.92-fold; P<0.01). Elevated caspase-3 activity (two- to threefold) was observed in NTN kidneys at all time points (P< 0.01). Upregulated expression of caspase-3 at all levels positively correlated with apoptosis, whereas both correlated closely with inflammation, proliferation, and subsequent fibrosis in glomeruli, tubules, and interstitium (P< 0.05). Inhibition of caspase-3 during the course of experimental nephritis may offer a new therapeutic approach for the prevention of renal apoptosis and the associated renal tubular atrophy and fibrosis.
Yang
Bin
B
Sheffield Kidney Institute, Northern General Hospital Trust, Sheffield, United Kingdom.
Johnson
Timothy S
TS
Sheffield Kidney Institute, Northern General Hospital Trust, Sheffield, United Kingdom.
Thomas
Graham L
GL
Sheffield Kidney Institute, Northern General Hospital Trust, Sheffield, United Kingdom.
Watson
Philip F
PF
Sheffield University Division of Clinical Sciences, Northern General Hospital Trust, Sheffield, United Kingdom.
Wagner
Bart
B
Department of Histopathology, Northern General Hospital Trust, Sheffield, United Kingdom.
Nahas
A Meguid El
AME
Sheffield Kidney Institute, Northern General Hospital Trust, Sheffield, United Kingdom.
D000818:Animals; D000906:Antibodies / Q000008:administration & dosage; D017209:Apoptosis; D001483:Base Sequence; D001485:Basement Membrane / Q000276:immunology; D053148:Caspase 3; D020169:Caspases / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division; D017931:DNA Primers / Q000235:genetics; D004195:Disease Models, Animal; D005921:Glomerulonephritis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology*; D007668:Kidney / Q000473:pathology / Q000503:physiopathology; D007678:Kidney Glomerulus / Q000276:immunology; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D011921:Rats, Inbred WKY
D000906:Antibodies; D017931:DNA Primers; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases