Expression of osteopontin in cisplatin-induced tubular injury.
Osteopontin (OPN) is considered as a key protein in cell regeneration. OPN is thought to have many functions in cell-cell binding and cell-matrix binding via OPN receptors in various organs. But there is little information on the precise role of OPN. To clarify the functional role of OPN in tubular injury, we performed in situ hybridization and immunohistochemical analysis of the expression of OPN in a renal cortical necrosis model induced by cisplatin from the acute injury to late recovery phases. In the acute injury phase, both mRNA and protein of OPN were markedly induced in damaged tubular lumens with cell debris. In the late recovery phase, on the other hand, OPN protein and mRNA were observed in dilated and flattened tubular epithelial cells showing a regenerative appearance. Most of these cells were also immunostained with CD44, a receptor of OPN. PCNA staining was also co-localized with these expressions. In light of the CD44 function regulating cell proliferation, these findings suggest that OPN may contribute to regeneration of tubular epithelial cells during the acute to late recovery phases of cortical tubular damage induced by cisplatin.
Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan. seita.iguchi@nifty.ne.jp
Seitaro
S
Iguchi
Shinichi
S
Nishi
Mika
M
Ikegame
Kazuto
K
Hoshi
Tatsuya
T
Yoshizawa
Hiroyuki
H
Kawashima
Masaaki
M
Arakawa
Hidehiro
H
Ozawa
Fumitake
F
Gejyo
D000818:Animals; D015152:Blotting, Northern / Q000379:methods; D015153:Blotting, Western / Q000379:methods; D002945:Cisplatin / Q000494:pharmacology*; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization / Q000379:methods; D007672:Kidney Cortex / Q000737:chemistry / Q000187:drug effects / Q000473:pathology; D007674:Kidney Diseases / Q000139:chemically induced*; D007684:Kidney Tubules / Q000737:chemistry / Q000187:drug effects* / Q000473:pathology*; D008297:Male; D053495:Osteopontin; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012795:Sialoglycoproteins / Q000096:biosynthesis* / Q000276:immunology
D012333:RNA, Messenger; D012795:Sialoglycoproteins; C506897:Spp1 protein, rat; D053495:Osteopontin; D002945:Cisplatin