Inhibition of corneal fibrosis by Smad7 in rats after photorefractive keratectomy  

作　　者：WANG Ti ZHOU Xing-tao YU Yan ZHU Jing-yin DAI Jin-hui QU Xiao-mei LE Qi-hua CHU Ren-yuan 

机构地区：[1]Department of Ophthalmology, Eye & ENT Hospital of FudanUniversity, Shanghai 20003 China [2]Department of Ophthalmology, the 85th Hospital of People'SLiliberation Army, Shanghai 200052, China [3]Department of Safety Assessment, Merck Research Laboratories,West Point, Pennsylvania, USA [4]Department of Ophthalmology, Huadong Hospital of FudanUniversity, Shanghai 200040, China

出　　处：《Chinese Medical Journal》2013年第8期1445-1450,共6页中华医学杂志（英文版）

摘　　要：Background Haze or corneal subepithelial fibrosis is one of the common complications after refractive surgery procedures, such as photorefractive keratectomy （PRK）, laser epithelial keratomileusis, and epipolis laser in situ keratomileusis, which would result in refractive regression, decreased visual quality, and corneal opacification. Haze directly resulted from corneal fibrosis mediated by transforming growth factor β （TGFβ）. SmadT, an inhibitory Smad, can inhibit TGFβ signal transduction. Recently, the effects of Smad7 on the inhibition of fibrosis in several organs have been studied, while little is known about the effects on cornea after PRK. This study was aimed to determine the effects of lentiviral-mediated Smad7 gene expression on corneal fibrosis in rats after PRK. Methods Four different experimental groups were established using right eyes of Sprague-Dawley rats. Thirty-two eyes underwent de-epithelialization only and served as a sham operation group （group 1）. Ninety-six eyes underwent PRK operation and were further divided into group 2 （the PRK group） without lentivector administration, group 3 （the Lv-blank group） with control lentiviral vector without Smad7 administration, and group 4 （the Lv-Smad7 group） with Smad7 expressing lentiviral vector Smad7 administration. At 1 day, 1 week, 1 month, and 3 months after PRK, the transfection efficiency was determined by measuring the fluorescence signal as well as Smad7 protein and mRNA levels. Corneas were further processed for immunoblotting to assess the phosphorylation of Smad2 as a downstream event of TGFβ/Smad signaling. The expression of fibrotic markers, such as c（-smooth muscle actin （c（-SMA）, Type III collagen （collagen III）, and cell cycle-related marker Ki67, was measured by quantitative real-time reverse transcription polymerase chain reaction （RT-PCR）. Results Lentivirus-mediated exogenous Smad7 gene expression in rat corneal tissue resulted in reduced activation of TGFβ/Smad signaling caused by doBackground Haze or corneal subepithelial fibrosis is one of the common complications after refractive surgery procedures, such as photorefractive keratectomy （PRK）, laser epithelial keratomileusis, and epipolis laser in situ keratomileusis, which would result in refractive regression, decreased visual quality, and corneal opacification. Haze directly resulted from corneal fibrosis mediated by transforming growth factor β （TGFβ）. SmadT, an inhibitory Smad, can inhibit TGFβ signal transduction. Recently, the effects of Smad7 on the inhibition of fibrosis in several organs have been studied, while little is known about the effects on cornea after PRK. This study was aimed to determine the effects of lentiviral-mediated Smad7 gene expression on corneal fibrosis in rats after PRK. Methods Four different experimental groups were established using right eyes of Sprague-Dawley rats. Thirty-two eyes underwent de-epithelialization only and served as a sham operation group （group 1）. Ninety-six eyes underwent PRK operation and were further divided into group 2 （the PRK group） without lentivector administration, group 3 （the Lv-blank group） with control lentiviral vector without Smad7 administration, and group 4 （the Lv-Smad7 group） with Smad7 expressing lentiviral vector Smad7 administration. At 1 day, 1 week, 1 month, and 3 months after PRK, the transfection efficiency was determined by measuring the fluorescence signal as well as Smad7 protein and mRNA levels. Corneas were further processed for immunoblotting to assess the phosphorylation of Smad2 as a downstream event of TGFβ/Smad signaling. The expression of fibrotic markers, such as c（-smooth muscle actin （c（-SMA）, Type III collagen （collagen III）, and cell cycle-related marker Ki67, was measured by quantitative real-time reverse transcription polymerase chain reaction （RT-PCR）. Results Lentivirus-mediated exogenous Smad7 gene expression in rat corneal tissue resulted in reduced activation of TGFβ/Smad signaling caused by do

关 键 词：CORNEA FIBROSIS Smad7 transforming growth factor β  gene therapy  photorefractive kerateetomy 

分 类 号：R779.6[医药卫生—眼科]