摘要
AIM:To investigate the mechanism of the tight junction(TJ) disruption and the association between tumor necrosis factor(TNF)-α and matrix metalloproteinase(MMPs) under hyperosmotic condition in primary human corneal epithelial cells(HCECs).METHODS:The cultured HCECs were exposed to media which adding sodium chloride(Na Cl) for hyperosmolar stress or adding rh-TNF-α(10 ng/m L). NF-κB inhibitor(5 μmol/L) or GM-6001(potent and broad spectrum MMP inhibitor, 20 μmol/L)was added 1 h before that treatment. The integrity of TJ proteins was determined by immunofluorescent(IF) staining. The m RNA levels of TNF-α and MMPs were evaluated by quantitative reverse transcription polymerase chain reaction(RT-q PCR) and the protein expression by enzyme-linked immunosorbent assay(ELISA).RESULTS:TJ proteins ZO-1 and Occludin were disrupted in primary HCECs exposed to hyperosmotic medium. The m RNA expression and protein production of TNF-α increased significantly in hyperosmotic media at 500 m Os M. TNF-α mediated the expression and production of MMP-1, MMP-13, MMP-9, and MMP-3 stimulated by hyperosmotic stress. The production of MMPs in hyperosmolar media were increased through the increase of TNF-α. GM-6001 prevent the destruction of ZO-1 and Occludin in hyperosmolar stress and rh-TNF-α treated medium. TNF-α induced activation of MMPs was involved in the TJ disruption by hyperosmolarity.CONCLUSION:TJ proteins ZO-1 and Occludin are disrupted by hyperosmolar stress and TNF-α, but protected by MMP inhibitor(GM-6001). It suggests that TNF-α/MMP pathway mediates the TJ disruption in primary HCECs exposed to hyperosmotic stress.
