[Apoptosis of lens epithelial cell induced by curcumin and its mechanism].
OBJECTIVE
To investigate the effects of natural drug curcumin (Cur) on apoptosis of lens epithelial cell (LEC) in vitro and its mechanism.


METHODS
The bovine LEC were cultured with Cur, the ultrastructure changes were observed under transmission electron microscope (TEM), the DNA content and mitochondrial transmembrane potential (DeltaPsim) changes were studied by flow cytometry (FCM).


RESULTS
The typical morphological changes of LEC apoptosis in Cur group detected by TEM included chromatin condensation and aggregation at the periphery of the nucleons and nuclear fragmentation. The DNA content of LEC in Cur group decreased time-dependently. The DNA content was significantly lower than that of the control group (P < 0.01). The DeltaPsim of LEC in Cur group was decreased, appeared in early stage (8 hours) and reached the maximum after 72 hours. The difference of DeltaPsim of LEC between Cur group and the control group was significant (P < 0.01).


CONCLUSIONS
Cur can remarkably induce apoptosis of LEC in vitro. Cur induced LEC apoptosis is caused by decrease of DNA content in LEC nucleus. Collapse of DeltaPsim in cytoplasm induced by Cur results in the irreversible apoptosis process of LEC. This is the early event of LEC apoptosis. LEC apoptosis induced by Cur may pass through two pathways: nuclear pathway and cytoplasmic pathway. The apoptosis of LEC induced by Cur may be the cellular and molecular mechanisms of reducing lens posterior capsular opacification by Cur. Cur may become an effective and low toxic medication for the prevention and treatment of after-cataract.
Huang
Xiu-rong
XR
Research Center of Pathophysiology, Fujian College of Traditional Chinese Medicine, Fuzhou 350003, China. qihuang@netease.com
Qi
Ming-xin
MX
Kang
Ke-ren
KR
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002386:Cataract / Q000517:prevention & control; D002417:Cattle; D002478:Cells, Cultured; D003474:Curcumin / Q000494:pharmacology*; D053938:DNA Fragmentation; D004847:Epithelial Cells / Q000648:ultrastructure*; D005434:Flow Cytometry; D007903:Lens Capsule, Crystalline / Q000473:pathology; D007908:Lens, Crystalline / Q000166:cytology*; D008564:Membrane Potentials; D008928:Mitochondria / Q000187:drug effects
D003474:Curcumin