Abstract:

Objective    To investigate the effects and mechanisms of tauroursodeoxycholic acid（TUDCA）on human lens epithelial cells （hLECs）in  a high glucose medium. Methods    HLECs were incubated in DMEM with different concentrations of glucose  for 24h. A model of apoptotic hLECs was established and exposed to TUDCA（0.2,0.5,1.0,2.0mmol/L）for 24h. The proliferation of hLECs was determined by MTT. Morphologic evaluation of apoptotic cells was performed by Hoechst 33258 staining and the apoptosis rate was measured by flow cytometry（FCM）after staining of Annexin V-FITC and PI. Western blot was used to determine the expression of GRP78. Results    After glucose treatment for 24h, the inhibition of cell proliferation was increased  with glucose concentration increasing（P<0.01）. Incubating the cells with high concentration of glucose（250mmol/L）for 24h inhibited the proliferation of hLECs and induced significant  cells apoptosis（P<0.01）. The Apoptosis percentage of hLECs was decreased and expression of Bip/GRP78 was markedly inhibited after coincubation with TUDCA（P<0.05）. Conclusions    Endoplasmic reticulum stress is involved in hLECs apoptosis induced by a high concentration of glucose. TUDCA inhibits hLECs apoptosis, thus protecting hLECs in vitro. The signal transduction mechanisms are related to endoplasmic reticulum stress.

Key words: Cataract；Tauroursodeoxycholic Acid；Endoplasmic reticulum；Apoptosis；Glucose