| Abstract |
Jin-Song HE, Satoshi HORIKOSHI, Kazuhiko FUNABIKI, Isao SHIRATO,
Yasuhiko TOMINO
Division of Nephrology, Department of Internal Medicine, Juntendo University
School of Medicine, Tokyo, Japan.
Objective: Products of intracellular mevalonate metabolism are
essential for cell growth and proliferation. Inhibition of mevalonate synthesis
by statins has been shown to suppress mesangial cell proliferation associated
with various glomerular diseases. In this study, we investigated the effect
of a new synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor,
NK-104, on cultured rat mesangial cell proliferation.
Methods: The cultured rat mesangial cells were stimulated by 10%
fetal calf serum or platelet-derived growth factor in the absence or presence
of NK-104 and mevalonate metabolites. 5-bromo-2-deoxyuridine incorporation was
used to assess DNA synthesis. In other experiments, Ras processing and mitogen-activated
protein kinase activation were analyzed by Western blotting.
Results: NK-104 inhibited fetal calf serum- or platelet-derived
growth factor-stimulated Ras processing and mitogen-activated protein kinase
activation. NK-104 also caused inhibition of fetal calf serum- or platelet-derived
growth factor-stimulated 5-bromo-2-deoxyuridine incorporation and cell proliferation.
Mevalonic acid, farnesyl pyrophosphate, and geranylgeranyl pyrophosphate significantly
prevented these inhibitory effects of NK-104.
Conclusions: The present results suggest that NK-104, by inhibiting
the synthesis of isoprenoid metabolites of mevalonate, may modulate Ras-mediated
signaling events associated with mesangial cell proliferation. (Hong Kong J
Nephrol 2001;3(2):67-73)
Key words: Mesangial cell, Mitogen-activated protein (MAP) kinase, Mevalonate metabolism, NK-104, Ras