Responses of cultured human keratocytes and myofibroblasts to ethyl pyruvate: a microarray analysis of gene expression.
OBJECTIVE
Ethyl pyruvate (EP) has pharmacologic effects that remediate cellular stress. In the organ-cultured murine lens, EP ameliorates oxidative stress, and in a rat cataract model, it attenuates cataract formation. However, corneal responses to EP have not been elucidated. In this study, the potential of EP as a therapeutic agent in corneal wound healing was determined by examining its effects on the transition of quiescent corneal stromal keratocytes into contractile myofibroblasts.


METHODS
Three independent preparations of cultured human keratocytes were treated with TGF-beta1, to elicit a phenotypic transition to myofibroblasts in the presence or absence of 10 or 15 mM EP. Gene expression profiles of the 12 samples (keratocytes +/- EP +/- TGF-beta1 for three preparations) were produced by using gene microarrays.


RESULTS
TGF-beta1-driven twofold changes in at least two of three experiments defined a group of 1961 genes. Genes showing twofold modulation by EP in at least two experiments appeared exclusively in myofibroblasts (857 genes), exclusively in keratocytes (409 genes), or in both phenotypes (252 genes). Analysis of these three EP-modulated groups showed that EP (1) inhibited myofibroblast proliferation with concomitant modulation of some cell cycle genes, (2) augmented the NRF2-mediated antioxidant response in both keratocytes and myofibroblasts, and (3) modified the TGF-beta1-driven transition of keratocytes to myofibroblasts by inhibiting the upregulation of a subset of profibrotic genes.


CONCLUSIONS
These EP-induced phenotypic changes in myofibroblasts indicate the potential of EP as a therapeutic agent in corneal wound healing.
Harvey
Stephen A K
SA
Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213-2588, USA. harveysa@upmc.edu
Guerriero
Emily
E
Charukamnoetkanok
Nahthai
N
Piluek
Jordan
J
Schuman
Joel S
JS
Sundarraj
Nirmala
N
D018797:Cell Cycle Proteins / Q000235:genetics; D002461:Cell Line, Transformed; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003319:Corneal Stroma / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D018816:Genes, cdc / Q000502:physiology; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D011773:Pyruvates / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology; D015854:Up-Regulation; D014945:Wound Healing / Q000187:drug effects
D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D011773:Pyruvates; D053773:Transforming Growth Factor beta1; C046522:ethyl pyruvate