Protective Effect of Heparin, Tenecteplase, and Zinc sulfate Against Induced Cataract in Rabbit

Cataract ; It refers to progressive increase in opacity of the eye lens. The result is reduced amount of light going to eye. Aim of the study To investigate if the cataract can be prevented and treated by drugs.
Materials and methods In vitro study (each group consists of 6 lenses) Prophylactic study The amount of 0.1 ml drug was added to the lenses once daily for 2 days before adding of 1 ml of 0.1% w/v of sodium selenite solution, and then adding of drugs persisted once daily for further 7 days. Treatment study In the treatment study, selenite solution 0.1% was added for 1 day, when the opacity occurred (grade 4) , the amount of 0.1 ml of drug was added to the cultured lenses once daily for further 28 days. In vivo study (Each group included 6 rabbits). The group of rabbits were anesthetized by intramuscular injection of 0.5 ml of (50 mg/ml) ketamin, the induction of disease was done by intravitreal injection of 0.1 ml of 0.01% w/v of sodium selenite solution in right eyes. Prophylactic study The tested agents (and distilled water) were administered topically 3 times/day for five days prior to induction of cataract and continued there after for further 21 days after the cataract being induced. Each of tested agents was administered only to the right eyes of the rabbits.Treatment study After the cataract was definitely established; the treatment divided in to; A- The tested agents were administered topically 3times/day to the right eyes of rabbits, for 42 days. B- Tested agents were weekly injected in the anterior chamber and intravitreal, for 42 days. The drug groups; Negative control (DW) group. Distilled water was administered to both eyes of rabbits, Heparin (5000 IU), enecteplase (10000IU) group group, and Zinc sulfate (0.25% ) group. Electron microscope (EM) study; at the end of trail period the lenses prepared to EM study. Results prophylaxis Heparin (5000IU/ml) in vitro, the mean score of opacity was (0.16± 0.01 ) at the day 7th of trial period , and there was no significant (p > 0.05) difference in comparing to pre induction. While in vivo the mean score of opacity was (4.0 ± 0.00) in DW group, in heparin group; the mean score was (0.17± 0.17) at the 21st day, and there was non significant difference (P > 0.05) when compared to preinduction. Tenecteplase (1000IU/ml) In vitro, the mean score was (0.8 ± 0.17 ) at the day 7th of trial period , and there was a highly significant (P<0.01) difference in comparing to pre induction. While in vivo; mean score was (1.5 ± 0.22) and there was a highly significant (P<0.01) difference in comparing to pre induction. Zinc sulfate (0.25%); In vitro, the mean score was (1.0 ± 0.00 ), and there was a highly significant (P<0.01) difference, while in vivo; there was a highly significant (P £ 0.01) difference in comparing to pre induction and the mean score was (1.33 ± 0. 21). EM study; each of heparin, tenecteplase, and zinc sulfate could prevented the aggregation of lens proteins. Treatment Heparin sodium (5000IU/ml); in vitro the mean score was (3.0 ± 0.00) at day 28th. While in vivo; as eye drop , could not affect the opacity ,While as intraocular injection, there was a highly significant ( P £ 0.01 ) reduction and 42nd and the mean score was (3.17 ± 0.17). Tenecteplase (1000IU/ml); in vitro, caused highly significant (P<0.01) reduction at day 28th ,the mean score was (1.2 ± 0.2). While in vivo; as eye drop tenecteplase caused a significant (0.01 ≤ p < 0.05) reduction in opacity (3.33 ± 0.21), while in injection the mean score was (1.33 ± 0.21) at day 42nd, which was highly significant (p < 0.01) reduction. Zinc sulfate (0.25%); zinc sulfate could not cause any reduction in the mean score of opacity in vitro and when administered as eye drop and intraocular injection. EM study; each of heparin and tenecteplase were able to dissolve the aggregated lens proteins, but zinc sulfate could not do so. Conclusions Each of heparin, tenecteplase, and zinc sulfate eye drops exerted detectable preventive effects against sodium selenite - induced cataract in rabbits, in vitro and in vivo. Tenecteplase at its both routes of administration (i.e., eye drops and intraocular injection), and in vitro, was therapeutically effective in reducing the extent of cataract after being induced by sodium selenite. Heparin injected intraocularly, and in vitro was therapeutically effective in reducing the extent of cataract after being induced by sodium selenite. Zinc sulfate could not effective therapeutically in vitro and in vivo. The tested drugs were found to be apparently safe and tolerable along the trial period.