Nuclear factor-kappaB activation in diabetic rat kidney: evidence for involvement of P-selectin in diabetic nephropathy.
Activation of a transcription factor, nuclear factor-kappaB (NF-kappaB), is a key step in the pathogenesis of diabetic nephropathy. In this study, we investigated the role of P-selectin, a platelet-derived adhesion molecule, in diabetic nephropathy by examining the activation status of NF-kappaB in the renal cortex of streptozotocin (STZ)-treated rats. The STZ treatment induced pathogenetic parameters such as increased creatinine clearance, increased blood glucose and massive albuminuria in a time-dependent manner. Electrophoretic mobility shift assays (EMSAs) with a specific probe, representing the P-selectin gene promoter, revealed the activation status of NF-kappaB in the STZ-treated rats, as judged by the time-dependent increase in the formation of the specific protein-DNA complexes. This increase was associated with the increased pathogenetic parameters. Supershift assays with specific antibodies revealed that p50, but not p52, p65, Rel B, or c-Rel, may be involved in the activation of NF-kappaB, though the component primarily responsible for the increase could not be determined. Western blot analysis confirmed an increase in P-selectin in STZ-treated rats. Notably, treatment with ammonium pyrrolidinedithiocarbamate, an antioxidant and inhibitor of NF-kappaB, inhibited the activation of NF-kappaB in STZ-treated rats and decreased P-selectin in the renal cortical tissue. Our results indicate that expression of the P-selectin gene is induced through the activation of NF-kappaB and that P-selectin may be involved in the pathogenesis of diabetic nephropathy.
Iwamoto
Masateru
M
Department of Nephrology, Toho University Faculty of Medicine, Tokyo, Japan.
Mizuiri
Sonoo
S
Arita
Michitsune
M
Hemmi
Hiromichi
H
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003928:Diabetic Nephropathies / Q000139:chemically induced / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D016328:NF-kappa B / Q000378:metabolism*; D019007:P-Selectin / Q000235:genetics / Q000378:metabolism*; D011759:Pyrrolidines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin / Q000494:pharmacology; D013859:Thiocarbamates / Q000494:pharmacology
D016328:NF-kappa B; D019007:P-Selectin; D011759:Pyrrolidines; D013859:Thiocarbamates; C020972:pyrrolidine dithiocarbamic acid; D013311:Streptozocin