title: The effects of ripasudil (K-115), a Rho kinase inhibitor, on activation of human conjunctival fibroblasts.
abstract: The most common cause of glaucoma surgery failure is scar formation induced by activation of wound-healing responses and resultant fibrosis at the surgical site. We investigated the effects of ripasudil, a Rho kinase inhibitor, on activation of human conjunctival fibroblasts (HConF). HConF were pretreated with different concentrations of ripasudil for 1 h before addition of transforming growth factor (TGF)-β2, followed by incubation for 48 h. TGF-β2-treated fibroblasts exhibited a significant increase in expression of α-smooth muscle actin (α-SMA), a marker of fibroblast-to-myofibroblast differentiation, and this increase was significantly suppressed, in a dose-dependent manner, by pretreatment with ripasudil. Ripasudil pretreatment also significantly attenuated TGF-β2-induced fibronectin production and collagen gel contraction. TGF-β2 increased both the number of viable cells and the number of cells in the G2/M phase of the cell cycle; these effects were attenuated by pretreatment with ripasudil. In addition, we explored the effects of ripasudil on stimulation of HConF by activated macrophages. Human monocytic cell line THP-1 cells were differentiated into M1 or M2 macrophage-like cells, and HConF were treated with conditioned media derived from these macrophages in the presence or absence of ripasudil. Conditioned medium from M2 macrophage-like cells induced a significant increase in α-SMA expression, viable cell numbers, and gel contraction, all of which were significantly suppressed by ripasudil. Thus, overall, ripasudil attenuated activation of human conjunctival fibroblasts. Ripasudil may be of therapeutic utility, preventing excessive scarring after glaucoma filtration surgery.
authors.affiliation: Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Futakuchi
authors.affiliation: Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan. Electronic address: noel@da2.so-net.ne.jp.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Fujimoto
authors.affiliation: Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Inoue-Mochita
authors.affiliation: Department of Ophthalmology, Asahikawa Medical University, Asahikawa, Japan.
authors.forename: Motofumi
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Tanihara
mesh_terms: D000199:Actins / Q000096:biosynthesis; D015153:Blotting, Western; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D002921:Cicatrix / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D003228:Conjunctiva / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D017077:Culture Media, Conditioned; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D018463:Filtering Surgery / Q000009:adverse effects; D005901:Glaucoma / Q000601:surgery*; D006801:Humans; D007150:Immunohistochemistry; D007546:Isoquinolines / Q000494:pharmacology*; D008264:Macrophages / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction; D013449:Sulfonamides / Q000494:pharmacology*; D053781:Transforming Growth Factor beta2 / Q000378:metabolism; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D017077:Culture Media, Conditioned; D007546:Isoquinolines; C584679:K-115; D013449:Sulfonamides; D053781:Transforming Growth Factor beta2; D054460:rho-Associated Kinases
keywords: Glaucoma; Human conjunctival fibroblasts; Macrophage; Myofibroblasts; Rho kinase inhibitor; Ripasudil (K-115); TGF-beta; Wound healing