An experimental study on the effects of curcumin on posterior capsule opacification in young rabbit eyes

Posterior capsule opacification (PCO) compromises vision development in infants after cataract surgery and lead to amblyopia. To observe the effects of curcumin on PCO in infant rabbits, curcumin was injected under the capaule and into the anterior chamber during phacoemulsification.

Seventy-five 1-month-old healthy New Zealand white rabbits were randomized into 3 groups, one eye of each rabbit was randomly selected to be operated. The operation involved continuous circular capsulorhexis, followed by hydrodissection with 0.6 ml each of balanced salt solution (BSS, group A), hydroxypropyl-β-dodextrin (HP-β-CD, 90 µg/ml, group B) or CUR-HP-β-CD (123 µg/ml, group C), respectively. After phacoemulsification, 0.4 ml of each drug solution was injected into the anterior chamber via an incision. The extent of corneal edema and the inflammatory response within the anterior chamber were considered as measures PCO and observed postoperatively. All eyes were examined 1 and 2 months postoperative by slit lamp microscopy and photography after pupil dilation. On the third day postoperative, 6 rabbits from each group were executed. Paraffin-embedded sections were stained with hematoxylin-eosin (HE) or terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL, indicative of apoptosis). Stained sections were observed under light microscopy. Proliferation of lens epithelial cells (LECs) was observed microscopically on day 3, day 7, month 1 and month 2 after the operation with HE staining.

The remission of cornea edema occurred earlier in group C than in groups A and B (P < 0.05); there were no significant differences between groups A and B. The remission of anterior chamber exudation in group C was earlier than those in groups A and B (P < 0.05). No significant difference in the times when PCO occurred, was observed among groups. Compared to groups A and B, the extent of PCO was less severe (P < 0.05). Three days after the operation, LECs aggregated at the orbit. Meanwhile, minor apoptosis was observed in all groups. One month after the operation transparent, cortex and proliferating LECs were observed near the orbit in groups A and B. Two months postoperative, heavy cortex proliferation was observed in all groups: epithelial cells migrated and aggregated at the posterior capsule and rearranged under the anterior capsule in the control group. Proliferation was also observed in group C, but to a less severe extent than in the other two groups.

CUR-HP-β-CD exerts an inhibitory effect on PCO.