Genistein produces reduction in growth and induces apoptosis of rat RPE-J cells.
OBJECTIVE
To investigate the effect of the tyrosine kinase inhibitor, genistein, on the growth of the retinal pigment epithelial (RPE) cell.


METHODS
The tyrosine kinase inhibitor, genistein, was administered in culture to the rat retinal pigment epithelial cell line, RPE-J. The effect on cell viability and growth was assessed by trypan blue dye exclusion. Induction of apoptosis was confirmed morphologically by light and electron microscopy and oligonucleosomal fragmentation was assessed by TUNEL and DNA ladder. Quantitation was undertaken by propidium iodide staining and photometric enzyme immunoassay. Western blot was performed to study poly-(ADP-ribose)-polymerase cleavage (PARP). To confirm the involvement of caspase, the caspase inhibitor z-VAD-fmk was employed. In addition, cell cycle phase was determined by flow cytometry.


RESULTS
We here demonstrate that genistein treatment of RPE-J cells produces a dose- and time-dependent growth inhibition. Genistein in higher concentration induces apoptosis of rat RPE-J cell. z-VAD-fmk inhibited this type of apoptosis and cleavage of PARP enzyme was demonstrated. Ten micromolar genistein inhibited cell proliferation by G(0)/G(1) arrest without inducing apoptosis of the major population. Whereas 50 microM genistein caused growth inhibition of RPE-J cells by G(2)/M arrest and subsequent apoptotic death.


CONCLUSIONS
Genistein inhibits RPE cell growth and induces apoptosis. The ability of genistein to inhibit the proliferation and to induce apoptosis of RPE cells could be potentially therapeutic for proliferative vitreoretinopathy.
Yoon
H S
HS
Department of Ophthalmology, Institute of Medical Science, Dong-A University College of Medicine, Pusan, South Korea.
Rho
S H
SH
Jeong
J H
JH
Yoon
S
S
Yoo
K S
KS
Yoo
Y H
YH
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D019833:Genistein / Q000494:pharmacology*; D007118:Immunoassay; D020287:In Situ Nick-End Labeling; D009707:Nucleosomes / Q000187:drug effects / Q000378:metabolism; D010783:Photometry; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011419:Propidium; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D051381:Rats; D013194:Staining and Labeling; D013997:Time Factors
D000590:Amino Acid Chloromethyl Ketones; D061945:Caspase Inhibitors; D004791:Enzyme Inhibitors; D009707:Nucleosomes; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D011419:Propidium; D019833:Genistein; D011065:Poly(ADP-ribose) Polymerases; D011505:Protein-Tyrosine Kinases; D020169:Caspases