PURPOSE: To examine the effects of blocking p38 mitogen-activated protein kinase (MAPK) on post-injury conjunctival scarring in mice. Its effects on the behaviors of cultured subconjunctival fibroblasts were also investigated. METHODS: An in vivo study was conducted using an adenoviral vector carrying a dominant-negative (DN)-p38MAPK gene. A circumferential incision was made in the equatorial conjunctiva by scissors in the right eye of generally anesthetized adult C57BL/6 mice. DN-p38MAPK-expressing adenoviral vector was topically applied. The left control eye received non-functioning adenoviral vector. At 2, 5, and 7 days (each, n=22) the eyes were processed for histological or immunohistochemical examination to evaluate the tissue scarring. The expressions of type-I collagen and growth factors were evaluated by real time-reverse transcriptase-polymerase chain reaction. The effects of p38MAPK inhibitor on the proliferation, migration, and fibrogenic gene/protein expression of cultured human fibroblasts were also studied. RESULTS: The in vivo DN-p38MAPK gene introduction blocked the phospho-p38 expression with reduction of myofibroblast generation and suppression of mRNA expression of connective tissue growth factor (CTGF) and monocyte/macrophage chemoattractant protein-1 (MCP-1) in the mouse-injured conjunctiva. Blocking p38MAPK signal in the fibroblasts by a chemical inhibitor counteracted TGFbeta1's enhancement of expressions of type-I collagen, fibronectin, and CTGF. It also retarded cell migration, but cell proliferation was unchanged. CONCLUSIONS: Inhibiting p38MAPK signal impairs the fibrogenic reaction induced by the subconjunctival fibroblasts in vivo and in vitro, suggesting its potential effectiveness in preventing excessive scarring following glaucoma filtering surgery.
PURPOSE: To examine the effects of blocking p38 mitogen-activated protein kinase (MAPK) on post-injury conjunctival scarring in mice. Its effects on the behaviors of cultured subconjunctival fibroblasts were also investigated. METHODS: An in vivo study was conducted using an adenoviral vector carrying a dominant-negative (DN)-p38MAPK gene. A circumferential incision was made in the equatorial conjunctiva by scissors in the right eye of generally anesthetized adult C57BL/6 mice. DN-p38MAPK-expressing adenoviral vector was topically applied. The left control eye received non-functioning adenoviral vector. At 2, 5, and 7 days (each, n=22) the eyes were processed for histological or immunohistochemical examination to evaluate the tissue scarring. The expressions of type-I collagen and growth factors were evaluated by real time-reverse transcriptase-polymerase chain reaction. The effects of p38MAPK inhibitor on the proliferation, migration, and fibrogenic gene/protein expression of cultured human fibroblasts were also studied. RESULTS: The in vivo DN-p38MAPK gene introduction blocked the phospho-p38 expression with reduction of myofibroblast generation and suppression of mRNA expression of connective tissue growth factor (CTGF) and monocyte/macrophage chemoattractant protein-1 (MCP-1) in the mouse-injured conjunctiva. Blocking p38MAPK signal in the fibroblasts by a chemical inhibitor counteracted TGFbeta1's enhancement of expressions of type-I collagen, fibronectin, and CTGF. It also retarded cell migration, but cell proliferation was unchanged. CONCLUSIONS: Inhibiting p38MAPK signal impairs the fibrogenic reaction induced by the subconjunctival fibroblasts in vivo and in vitro, suggesting its potential effectiveness in preventing excessive scarring following glaucoma filtering surgery.
Authors: Yuka Okada; Kumi Shirai; Peter S Reinach; Ai Kitano-Izutani; Masayasu Miyajima; Kathleen C Flanders; James V Jester; Makoto Tominaga; Shizuya Saika Journal: Lab Invest Date: 2014-07-28 Impact factor: 5.662
Authors: Nobuhiro Kanaji; Amy Nelson; Diane S Allen-Gipson; Tadashi Sato; Masanori Nakanishi; Xingqi Wang; YingJi Li; Hesham Basma; Joel Michalski; Maha Farid; Stephen I Rennard; Xiangde Liu Journal: Inflamm Res Date: 2011-12-03 Impact factor: 4.575