Effect of tranilast microspheres (tranilast-MS) in preventing PCO in the rabbit

Objective To evaluate the effects of tranilast-MS on the prevention of PCO after in vivo rabbit eyes were treated with tranilast-MS.Methods Forty-seven rabbit eyes were randomly divided into 8 groups according to treatment protocols: three tranilast-MS groups (2 mg, 1 mg, 0.5 mg), microspheres without tranilast group, dexamethasone group, tranilast crystals group, medium group, and normal control group. A standard phacoemulsification operation was performed on the eyes in all of the groups, and this was followed by treatment with the solutions listed above. On 30, 60, and 90 days postoperatively, the animals were monitored in vivo for anterior reaction, intraocular pressure (IOP), and for the presence of PCO by using a high-resolution imaging analysis system. Histological examination was performed 12 weeks after surgery.Results In this study we found that, apart from the control group, the anterior chamber reaction was severe and persisted for a long time after treatment, but IOP did not increase significantly. By using a high-resolution imaging system, we found that the degree of PCO was less severe in the tranilast-MS groups than in the other groups. Moreover, there were significant differences among the tranilast-MS groups. Histological examination did not show significant LEC proliferation in the tranilast-MS groups or obvious damage to the cornea or iris in any of the groups 3 months after surgery.Conclusion Our study suggests that tranilast-MS is a potential agent for prevention of PCO and is less toxic to surrounding ocular tissue.