The effects of sodium orthovanadate-induced phosphatase inhibition on rat retinal pigment epithelium cell activity.
OBJECTIVE
The purpose of this study was to assess the contribution of sodium orthovanadate (SOV)-induced phosphatase inhibition to the activation of rat retinal pigment epithelium (RPE) cells.


METHODS
Confluent cultures of rat RPE cells were treated with the general phosphatase inhibitor SOV. The effects of SOV on the cell cycle were determined by flow cytometry and protein detection of cyclin A and cyclin D1, two different cell cycle regulatory factors. The effects of SOV on cell differentiation were confirmed by immunostaining for α-smooth muscle actin (α-SMA). A migration assay was used to evaluate the effects of SOV on cell migration.


RESULTS
SOV could accelerate the cell cycle of RPE cells. Western blotting showed that SOV significantly increased the expression of cyclin A and cyclin D1 in a dose-dependent fashion. The results of α-SMA staining and western blotting demonstrated that SOV induced RPE cells to differentiate toward better contractility and motility. The migration assay indicated that SOV improved the migration activity of RPE cells.


CONCLUSIONS
Sodium orthovanadate can improve proliferation, differentiation, and migration of rat RPE cells and can also induce the reentry of contact-inhibited rat RPE cells into the cell cycle.
Du
Zhao-Dong
ZD
Peking University Eye Center, Peking University Third Hospital, Beijing, China.
Hu
Li-Ting
LT
Hu
Yun-Tao
YT
Ma
Zhi-Zhong
ZZ
D000199:Actins / Q000378:metabolism; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D056750:Cyclin A1 / Q000378:metabolism; D019938:Cyclin D1 / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D007124:Immunoenzyme Techniques; D008297:Male; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors*; D051381:Rats; D017207:Rats, Sprague-Dawley; D055213:Retinal Pigment Epithelium / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D014638:Vanadates / Q000494:pharmacology*
D000199:Actins; C503748:Ccna1 protein, rat; C530106:Ccnd1 protein, rat; D056750:Cyclin A1; D004791:Enzyme Inhibitors; D019938:Cyclin D1; D014638:Vanadates; D010744:Phosphoric Monoester Hydrolases