Effect of liposome-encapsulated total alkaloid of harmaline on rabbit lens epithelial cells: experimental study on the prevention of posterior capsule opacification.
OBJECTIVE
To investigate whether liposome encapsulated total alkaloid of Harmaline (TAH) as a therapeutic agent is beneficial to prevention of posterior capsular opacification (PCO).


METHODS
Liposome-encapsulated TAH was prepared by modified freeze-thawing method. 0.1 ml of liposome-encapsulated TAH (0.2 mg/ml) was injected into the capsular bag during extracapsular lens extraction (ECLE) of each eye in total 10 rabbit eyes. Blank liposome or balance salt solution (BSS) was used as control. Slit-lamp examination and histopathological examination was used to evaluated capsule opacification. Intraocular pressure (IOP), density and morphology of corneal endothelia cells, the amplitude and latency of b wave of ERG were measured.


RESULTS
The inflammatory response was mild both in TAH treated and the control group. PCO formation occurred in the control group 2 weeks postoperatively, but the posterior capsule was clear in TAH treated eyes. 4 weeks and 8 weeks after operation, PCO occurred both in TAH treated and control eyes. However, it was milder in the TAH treated eyes. IOP remained at the normal level in all eyes. There was no difference in the density of corneal endothelial cells, and the amplitude and latency of b wave of ERG between TAH treated and control eyes. Histopathological study revealed that lens epithelial proliferation occurred 4 weeks and the Soemmerings ring developed 8 weeks postoperatively in the control eyes. However, only mild vacuolization and pkynotic changes of lens epithelial cells were found in TAH treated eyes. Transmmission electronic microscopy demonstrated that there were mild cytoplasm vacuolization and mitochondria swelling of lens epithelial cells in TAH treated eyes.


CONCLUSIONS
The results suggest that liposome encapsulated TAH can inhibit metaplasia and proliferation of lens epithelial cells in the rabbit eye without obvious toxicity to the eye tissue. It may be used as a potential agent to prevent the development of PCO.
Wu
M
M
Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Science, Guangzhou 510060, China.
Li
H
H
Li
S
S
Pan
S
S
D000470:Alkaloids / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D002386:Cataract / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D002387:Cataract Extraction / Q000009:adverse effects*; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D006246:Harmaline / Q000008:administration & dosage / Q000494:pharmacology*; D007429:Intraocular Pressure; D007903:Lens Capsule, Crystalline / Q000187:drug effects / Q000473:pathology*; D007908:Lens, Crystalline / Q000187:drug effects / Q000473:pathology; D007909:Lenses; D008081:Liposomes / Q000008:administration & dosage / Q000494:pharmacology*; D011817:Rabbits; D014792:Visual Acuity
D000470:Alkaloids; D008081:Liposomes; D006246:Harmaline