Korean J Physiol Pharmacol.
1997 Feb;1(1):35-43.
Effect of cisplatin on sodium-dependent hexose transport in LLC-PK-1
renal epithelial cells
- Affiliations
-
- 1
Departments of Otolaryngology, Physiology, and Microbiology Kosin Medical, Pusan 602-030 South Korea.
Abstract
-
Cis-dichlorodiammine platinum II (Cisplatin), an effective
chemotherapeutic agent, induces acute renal failure by unknown
mechanisms. To investigate direct toxic effects of cisplatin on the
renal proximal tubular transport system, LLC-PK-1 cell line was
selected as a cell model and the sugar transport activity was evaluated
during a course of cisplatin treatment. Cells grown to confluence were
treated with cisplatin for 60 min, washed, and then incubated for up to
5 days. At appropriate intervals, cells were tested for sugar transport
activity using alpha-methyl-D-(14C)glucopyranoside (AMG) as a model
substrate. In cells treated with 100 micrometer cisplatin, the AMG uptake was
progressively impaired after 3 days. The viability of cells was not
substantially changed with cisplatin of less than 100 micrometer, but it
decreased markedly with 150 and 200 micrometer. In cisplatin-treated cells,
the Na+/-dependent AMG uptake was drastically inhibited with no change
in the Na+/-independent uptake. Kinetic analysis indicated that Vmax was
suppressed, but Km was not altered. The Na+/-dependent phlorizin binding
was also decreased in cisplatin-treated cells. However, the AMG efflux
from preloaded cells was not apparently retarded by cisplatin
treatment. These data indicate that the cisplatin treatment impairs
Na+/-hexose cotransporters in LLC-PK-1 cells and suggest strongly that
defects in transporter function at the luminal plasma membrane of the
proximal tubular cells constitute an important pathogenic mechanism of
cisplatin nephrotoxicity.