Methotrexate induces cell swelling and necrosis in renal tubular cells.
BACKGROUND
The present study was carried out to investigate if methotrexate (MTX) has a direct lethal effect in renal tubular cells, and if so, to further clarify the mechanisms of cell death.


METHODS
Renal tubular cells (LLC-PK(1) cells) were incubated with MTX (0.01 microM, 0.1 microM, and 1 microM), either alone or in combination with 0.1 microM amiloride (Na(+)/H(+) antiporter inhibitor) or 1 microM carbachol (M-cholinergic agonist). Cell viability was then determined by means of trypan blue (TB) exclusion tests and MTT assays.


RESULTS
After 4 hr incubation with 0.1 microM MTX the number of viable cells was decreased by 18% in comparison with control cells, and the proportion of dead cells was increased by 38%. Cell death induced by MTX was time-dependent and did not show apoptotic features. On the contrary, cell swelling was discovered. This cell death was prevented by co-incubating the cells with amiloride or carbachol.


CONCLUSIONS
MTX induces cell swelling and cell death in renal tubular LLC-PK(1) cells. The tubular cell death induced by MTX is time-dependent. Cell death can be prevented by co-incubating with amiloride, thus indicating that the Na(+)/H(+) antiporter and possibly other volume regulatory factors in renal tubular cells are involved in MTX-induced renal failure.
Grönroos
Marika
M
Department of Paediatrics, Turku University Central Hospital, Turku, Finland. marika.gronroos@utu.fi
Chen
Ming
M
Jahnukainen
Timo
T
Capitanio
Arrigo
A
Aizman
Roman I
RI
Celsi
Gianni
G
D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D048429:Cell Size / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects*; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000473:pathology; D018374:LLC-PK1 Cells / Q000166:cytology / Q000187:drug effects; D008727:Methotrexate / Q000494:pharmacology*; D009336:Necrosis; D026941:Sodium Channel Blockers / Q000494:pharmacology; D013552:Swine
D000964:Antimetabolites, Antineoplastic; D026941:Sodium Channel Blockers; D000584:Amiloride; D008727:Methotrexate