Nitric oxide modulates expression of cell cycle regulatory proteins - A cytostatic strategy for inhibition of human vascular smooth muscle cell proliferation
Fc. Tanner et al., Nitric oxide modulates expression of cell cycle regulatory proteins - A cytostatic strategy for inhibition of human vascular smooth muscle cell proliferation, CIRCULATION, 101(16), 2000, pp. 1982-1989
Citations number
34
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Background-We examined the effect of NO on the proliferation and cell cycle
regulation of human aortic vascular smooth muscle cells (VSMCs).
Methods and Results-The NO donor diethylenetriamineNONOate (10(-5) to 10(-3
) mol/L) inhibited proliferation in response to 10% fetal calf serum (FCS)
and 100 ng/mL platelet-derived growth factor-BE in a concentration-dependen
t manner. This effect was not observed with disintegrated diethylenetriamin
eNONOate or with the parent compound, diethylene-triamine, Adenoviral trans
fection of endothelial NO synthase (NOS) inhibited proliferation in respons
e to FCS, which was prevented with N-G-nitro-L-arginine methyl ester. NOS o
verexpression did not inhibit proliferation in response to platelet-derived
growth factor, although the transfection efficiency and protein expression
were similar to those of FCS-stimulated cells. Nitrate release was selecti
vely enhanced from FCS-treated cells, indicating that NOS was activated by
FCS only. NO caused G(1) cell cycle arrest. Cytotoxicity was determined wit
h trypan blue exclusion, and apoptosis was assessed with DNA fragmentation.
Cyclin-dependent kinase 2 expression level, threonine phosphorylation, and
kinase activity were inhibited. Cyclin A expression was blunted, whereas c
yclin E remained unchanged. p21 expression was induced, and p27 remained un
altered. The effect on cyclin A and p21 started within 6 hours and preceded
the changes in cell cycle distribution. Proliferation in response to 10% F
CS was barely inhibited with 8-bromo-cCMP (10(-3) mol/L) but was blunted wi
th both forskolin and 8-bromo-cAMP. Proliferation in response to 2% FCS was
inhibited with 8-bromo-cGMP, but it did not mimic the cell cycle effects o
f NO.
Conclusions-NO inhibits VSMC proliferation by specifically changing the exp
ression and activity of cell cycle regulatory proteins, which may occur ind
ependent of cGMP. Adenoviral overexpression of endothelial NOS represents a
cytostatic strategy for gene therapy of vascular disease.