Antiproliferative effect of intravitreal alpha-tocopherol and alpha-tocopheryl-acid-succinate in a rabbit model of PVR.
OBJECTIVE
To evaluate the antiproliferative properties of alpha-tocopherol and alpha-tocopheryl-acid-succinate in a rabbit model of proliferative vitreoretinopathy.


METHODS
Fifty-seven rabbits underwent gas-compression vitrectomy and gas/fluid exchange. Group 1 (n = 8): 50 micrograms alpha-tocopherol in 1 ml of 0.5% ethanol in balanced salt solution; Group 2 (n = 8): 50 micrograms alpha-tocopheryl-acid-succinate in 1 ml of 0.5% ethanol in balanced salt solution; Groups 3 (n = 4) and 4 (n = 2): 1 ml 0.5% ethanol in balanced salt solution; Groups 5 (n = 12) and 8 (n = 9): alpha-tocopherol in 1 ml silicone oil (12 mg/ml); Group 6 (n = 9): 1 ml silicone oil; Group 7 (n = 5): 1 ml balanced salt solution. Groups 1-3, and 5-7 also received fibroblasts and platelet-rich plasma injection. Fundus evaluation was performed during a four-week period. The eyes were enucleated for gross examination on day 28. Histopathology was performed on Group 4.


RESULTS
Alpha-tocopherol and alpha-tocopheryl-acid-succinate in saline solution delayed development of proliferative vitreoretinopathy, compared to the control group (statistically significant during the first week, Mann Whitney, p < 0.05). The alpha-tocopherol in the silicone-oil group delayed development of proliferative vitreoretinopathy, compared to the silicone-oil group during the second to fourth weeks (no statistically significant difference, p > 0.05).


CONCLUSIONS
Alpha-tocopherol and alpha-tocopheryl-acid-succinate in saline solution showed retardation of proliferative vitreoretinopathy traction retinal detachments. In silicone oil, alpha-tocopherol is slowly released and decreases the severity of proliferative vitreoretinopathy, especially during the second week of follow-up.
Larrosa
J M
JM
Schepens Eye Research Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114-2500, USA.
Veloso
A A
AA
Leong
F L
FL
Refojo
M F
MF
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004195:Disease Models, Animal; D000431:Ethanol / Q000008:administration & dosage; D011817:Rabbits; D012163:Retinal Detachment / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D012827:Silicone Oils / Q000008:administration & dosage; D024505:Tocopherols; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000494:pharmacology*; D018630:Vitreoretinopathy, Proliferative / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D014822:Vitreous Body
D012827:Silicone Oils; D014810:Vitamin E; D000431:Ethanol; D024505:Tocopherols