Dataset Information

Electrophilic PPAR? ligands inhibit corneal fibroblast to myofibroblast differentiation in vitro: a potentially novel therapy for corneal scarring.

ABSTRACT: A critical component of corneal scarring is the TGF?-induced differentiation of corneal keratocytes into myofibroblasts. Inhibitors of this differentiation are potentially therapeutic for corneal scarring. In this study, we tested the relative effectiveness and mechanisms of action of two electrophilic peroxisome proliferator-activated receptor gamma (PPAR?) ligands: cyano-3,12-dioxolean-1,9-dien-28-oic acid-methyl ester (CDDO-Me) and 15-deoxy-?(-12,14)-prostaglandin J(2) (15d-PGJ(2)) for inhibiting TGF?-induced myofibroblast differentiation in vitro. TGF? was used to induce myofibroblast differentiation in cultured, primary human corneal fibroblasts. CDDO-Me and 15d-PGJ(2) were added to cultures to test their ability to inhibit this process. Myofibroblast differentiation was assessed by measuring the expression of myofibroblast-specific proteins (?SMA, collagen I, and fibronectin) and mRNA (?SMA and collagen III). The role of PPAR? in the inhibition of myofibroblast differentiation by these agents was tested in genetically and pharmacologically manipulated cells. Finally, we assayed the importance of electrophilicity in the actions of these agents on TGF?-induced ?SMA expression via Western blotting and immunofluorescence. Both electrophilic PPAR? ligands (CDDO-Me and 15d-PGJ(2)) potently inhibited TGF?-induced myofibroblast differentiation, but PPAR? was only partially required for inhibition of myofibroblast differentiation by either agent. Electrophilic PPAR? ligands were able to inhibit myofibroblast differentiation more potently than non-electrophilic PPAR? ligands, suggesting an important role of electrophilicity in this process. CDDO-Me and 15d-PGJ(2) are strong inhibitors of TGF?-induced corneal fibroblast to myofibroblast differentiation in vitro, suggesting this class of agents as potential novel therapies for corneal scarring warranting further study in pre-clinical animal models.

SUBMITTER: Kuriyan AE

PROVIDER: S-EPMC3259184 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Electrophilic PPARγ ligands inhibit corneal fibroblast to myofibroblast differentiation in vitro: a potentially novel therapy for corneal scarring.

Kuriyan A E AE Lehmann G M GM Kulkarni A A AA Woeller C F CF Feldon S E SE Hindman H B HB Sime P J PJ Huxlin K R KR Phipps R P RP

Experimental eye research 20111208 1

A critical component of corneal scarring is the TGFβ-induced differentiation of corneal keratocytes into myofibroblasts. Inhibitors of this differentiation are potentially therapeutic for corneal scarring. In this study, we tested the relative effectiveness and mechanisms of action of two electrophilic peroxisome proliferator-activated receptor gamma (PPARγ) ligands: cyano-3,12-dioxolean-1,9-dien-28-oic acid-methyl ester (CDDO-Me) and 15-deoxy-Δ(-12,14)-prostaglandin J(2) (15d-PGJ(2)) for inhibi ...[more]

PMID: 22178289

Similar Datasets

Project description:The transformation of keratocytes and fibroblasts to myofibroblasts is important to corneal wound healing as well as formation of stromal haze. The purpose of this study was to determine the effect of latrunculin B, an actin cytoskeleton disruptor in conjunction with a fundamental biophysical cue, substrate stiffness, on myofibroblast transformation in vitro and in vivo. Rabbit corneal fibroblasts were cultured on substrates of differing compliance (1.5, 22, and 71?kPa) and tissue culture plastic (TCP; > 1?GPa) in media containing 0 or 10?ng/ml TGF?1 for 72?h. Cells were treated with 0.4??M Lat-B or DMSO for 30?min every 24?h for 72?h. RNA was collected from cells and expression of alpha-smooth muscle actin (?-SMA), keratocan, and ALDH1A1 determined using qPCR; immunocytochemistry was used to assess ?-SMA protein expression. A rabbit phototherapeutic keratectomy (PTK) model was used to assess the impact of 0.1% Lat-B (n?=?3) or 25% DMSO (vehicle control, n?=?3) on corneal wound healing by assessment of epithelial wound size with fluorescein stain and semi-quantitative stromal haze scoring by an observer masked to treatment group as well as Fourier-domain optical coherence tomography (FD-OCT) at set time points. Statistical analysis was completed using one-way or two-way analysis of variance. Treatment with Lat-B versus DMSO resulted in significantly less ?SMA mRNA (P???0.007) for RCF cells grown on 22 and 71?kPa substrates as well as TCP without or with TGF?1, and significantly decreased ?-SMA protein expression in RCFs cultured on the intermediate (22?kPa) stiffness in the absence (P?=?0.028) or presence (P?=?0.018) of TGF?1. Treatment with Lat-B versus DMSO but did not significantly alter expression of keratocan or ALDH1A1 mRNA in RCFs (P?>?0.05) in the absence or presence of TGF?1, but RCFs grown on stiff hydrogels (71?kPa) had significantly more keratocan mRNA expression versus the 22?kPa hydrogel or TCP (P?<?0.001) without TGF?1. Administration of topical Lat-B BID was well tolerated by rabbits post-PTK but did not significantly alter epithelial wound closure, stromal haze score, stromal haze thickness as measured by FD-OCT in comparison to DMSO-treated rabbits. When corneal stromal cells are cultured on substrates possessing biologically relevant substratum stiffnesses, Lat-B modulates mRNA and protein expression of ?-SMA and thus modulates myofibroblast transformation. At a dose and dose-frequency that reduced IOP in human glaucoma patients, Lat-B treatment did not substantially impact corneal epithelial or stromal wound healing in a rabbit PTK model. While a significant impact on wound healing was observed at the concentration and dose frequency reported here was not found, encouraging in vitro data support further investigations of topically applied Lat-B to determine if this compound can reduce stromal fibrosis.

Project description:Fibroblast growth factor (FGF) signaling has been implicated in the pathogenesis of pulmonary fibrosis. Mice lacking FGF2 have increased mortality and impaired epithelial recovery after bleomycin exposure, supporting a protective or reparative function following lung injury. To determine whether FGF2 overexpression reduces bleomycin-induced injury, we developed an inducible genetic system to express FGF2 in type II pneumocytes. Double-transgenic (DTG) mice with doxycycline-inducible overexpression of human FGF2 (SPC-rtTA;TRE-hFGF2) or single-transgenic controls were administered intratracheal bleomycin and fed doxycycline chow, starting at either day 0 or day 7. In addition, wild-type mice received intratracheal or intravenous recombinant FGF2, starting at the time of bleomycin treatment. Compared to controls, doxycycline-induced DTG mice had decreased pulmonary fibrosis 21 days after bleomycin, as assessed by gene expression and histology. This beneficial effect was seen when FGF2 overexpression was induced at day 0 or day 7 after bleomycin. FGF2 overexpression did not alter epithelial gene expression, bronchoalveolar lavage cellularity or total protein. In vitro studies using primary mouse and human lung fibroblasts showed that FGF2 strongly inhibited baseline and TGFβ1-induced expression of alpha smooth muscle actin (αSMA), collagen, and connective tissue growth factor. While FGF2 did not suppress phosphorylation of Smad2 or Smad-dependent gene expression, FGF2 inhibited TGFβ1-induced stress fiber formation and serum response factor-dependent gene expression. FGF2 inhibition of stress fiber formation and αSMA requires FGF receptor 1 (FGFR1) and downstream MEK/ERK, but not AKT signaling. In summary, overexpression of FGF2 protects against bleomycin-induced pulmonary fibrosis in vivo and reverses TGFβ1-induced collagen and αSMA expression and stress fiber formation in lung fibroblasts in vitro, without affecting either inflammation or epithelial gene expression. Our results suggest that in the lung, FGF2 is antifibrotic in part through decreased collagen expression and fibroblast to myofibroblast differentiation. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Dataset Information

Electrophilic PPAR? ligands inhibit corneal fibroblast to myofibroblast differentiation in vitro: a potentially novel therapy for corneal scarring.

Publications

Electrophilic PPARγ ligands inhibit corneal fibroblast to myofibroblast differentiation in vitro: a potentially novel therapy for corneal scarring.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets