Method: Cadherin-11 expression in rat temporomandibular SFs was evaluated using immunofluorescence staining.HP was applied on cultured SFs at different levels for 12h.Quantitative real-time RT-PCR and western blot were applied to analyze the cadherin-11 expression levels.Time-course dependent expression of cadherin-11 was also performed by stimulating with 10ng/ml TNF-α.Quantitative real-time RT-PCR was used to detect a variety of cell activation associated factor gene expression.Extraction of total protein was for Western blot detection of a variety of signal-line protein expression.
Result: Immunofluorescence analysis revealed that the cadherin-11 is abundantly expressed at the edge of cell-to-cell junction,connecting tightly with F-actin cytoskeleton.Our study showed that the mRNA and protein expression of cadherin-11 were significantly increased after HP stress and TNF-αtreatment in a magnitude and time-course dependent manners.Both 90kPa HP stress and 10ng/ml TNF-α can significantly enhance PI3K and Akt phosphorylation, and Akt phosphorylation inhibitor LY294002 can inhibit the phosphorylation level of Akt.The experiment also found that HP stress and TNF-αsignificantly enhanced the expression of cadherin-11,FGF-1,FGF-2 and VEGF protein,and promote cadherin-11,FGF-1,FGF-2 and VEGF-D gene expression.The enhancement could be prohibited by LY294002.
Conclusion: Our study demonstrated that the exposure of SFs to HP and TNF-α could induce the expression of cadherin-11, FGF-1,FGF-2 and VEGF by the PI3K/Akt pathway,which were inhibited by the inhibitor of Akt pathway,LY294002.Our study demonstrated that the exposure of SFs to HP and TNF-α could induce the expression of cadherin-11,FGF-1,FGF-2 and VEGF by the PI3K/Akt pathway,which were inhibited by the inhibitor of Akt pathway,LY294002.