title: Effect of apigenin on gap junctional intercellular communication in human Tenon's capsule fibroblasts.
abstract: OBJECTIVE
  To investigate the effect of apigenin on gap junctional intercellular communication (GJIC) in human Tenon's capsule fibroblasts (HTFs) and its underlying mechanism.
  
  
  METHODS
  After a 48 h treatment of cultured HTFs with apigenin (80 micromol/L), the GJIC was detected by a scrape-loading/dye transfer technique with Lucifer yellow dye and rhodamine (Rh) dextran. The coupling index represents a quantification of GJIC where a high coupling index is associated with a greater number of cells demonstrating cell-cell communication through gap junction channels. The changes in connexin 43 (Cx43) distribution and the expression of Cx43 at the protein and mRNA levels were statistically compared between the two groups by means of immunocytochemistry, western blotting, and real-time polymerase chain reaction (PCR).
  
  
  RESULTS
  The functioning of GJIC in the HTFs was significantly enhanced after 48 hours by apigenin treatment when compared with the control cells. In the apigenin group, the intercellular dye transfer grade was above 9, while this value was only grade 3-4 in the control group. The coupling index was significantly increased up to 9.205+/-0.3621 in the apigenin group, compared with 5.1775+/-0.3177 in the control group (F=279.581, P=0.000). The expression of Cx43 at the protein and mRNA levels was significantly up-regulated in the apigenin group compared with the control group.
  
  
  CONCLUSIONS
  Apigenin can significantly enhance the function of GJIC in HTFs by up-regulating the expression of Cx43 at both the protein and mRNA levels, suggesting that the enhancement of GJIC in HTFs by apigenin probably acts as an important mechanism underlying the inhibitory effect of apigenin on HTF proliferation.
authors.affiliation: Department of Ophthalmology, Weifang Medical University, Weifang 261042, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Weifang Eye Hospital, National Key Clinical Constructive Project Unit of Ophthalmology, Weifang 261042, China.
authors.forename: Jibing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Dezhou People's Hospital, Dezhou 253000, China.
authors.forename: Huihui
authors.initials: H
authors.lastname: Zou
authors.affiliation: Weifang Eye Hospital, National Key Clinical Constructive Project Unit of Ophthalmology, Weifang 261042, China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Huang
mesh_terms: D047310:Apigenin / Q000494:pharmacology*; D015153:Blotting, Western; D002450:Cell Communication / Q000187:drug effects* / Q000502:physiology; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects* / Q000502:physiology; D017629:Gap Junctions / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D058475:Tenon Capsule / Q000166:cytology*; D015854:Up-Regulation
chemical_list: D018031:Connexin 43; D012333:RNA, Messenger; D047310:Apigenin