title: Effects of insulin-like growth factor 2 and its receptor expressions on corneal repair.
abstract: Limbal stem cell (LSC) on the basal layer of cornea plays an important role in the epithelial repair after corneal injury as it can proliferate, differentiate and migrate into injury sites under the direction of cytokines. This study explored the signaling pathway and cellular mechanism between corneal epithelial cells LSC, on a mouse model with mechanic corneal injury. Ipsilateral corneal mechanic injury model was prepared on mice using the contralateral eye as the control. Tissues from both central and peripheral regions of cornea were collected, cultured and quantified for expression of various cytokines including epidermal growth factor (EGF), fibroblast growth factor-β (FGF-β), heparin-like growth factor (HGF), keratinocyte growth factor (KGF), transforming growth factor-β1 (TGF-β1), IGF-1 and IGF-2. The effects of these factors on the differentiation of LSC and fibroblasts were also studied. Most of those cytokines had elevated gene expressions after the corneal injury. Among those IGF-2 had significantly increased expression, along with the high expression of IGF-2 receptor in corneal peripheral cells. IGF-2 also induced the differentiation of LSC into keratin-12-positive cells. Further studies showed the prominent expression of α-actin in injured tissues, suggesting the potential transformation of fibroblasts into myofibroblasts. Both IGF-2 and its receptor had elevated expressions after corneal injury. They may facilitate the transformation of LSC into epithelial cells, in addition to the role in transformation from fibroblasts to myofibroblasts.
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021, China ; Department of Ophthalmology, Weifang People's Hospital Weifang 261041, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Ophthalmology, Weifang People's Hospital Weifang 261041, China.
authors.forename: Zhicai
authors.initials: Z
authors.lastname: Ju
authors.affiliation: Department of Ophthalmology, Weifang People's Hospital Weifang 261041, China.
authors.forename: Junfu
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Weifang People's Hospital Weifang 261041, China.
authors.forename: Xinchang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Ophthalmology, Weifang People's Hospital Weifang 261041, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Tian
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021, China.
authors.forename: Guoying
authors.initials: G
authors.lastname: Mu
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism*; D065306:Corneal Injuries / Q000235:genetics / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism; D051523:Fibroblast Growth Factor 7 / Q000235:genetics / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D017527:Receptor, IGF Type 2 / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing
chemical_list: D017527:Receptor, IGF Type 2; D051523:Fibroblast Growth Factor 7; D005346:Fibroblast Growth Factors; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II
keywords: Corneal injury and repair; fibroblasts; insulin-like growth factor-2; myofibroblasts