Seong Hyemin, Ryu Jinhyun, Yoo Woong-Sun, Kim Seong Jae, Han Yong-Seop, Park Jong Moon, Kang Sang Soo, Seo Seong Wook
a Department of Anatomy and Convergence Medical Science, College of Medicine , Gyeongsang National University , Jinju , Gyeongnam , Republic of Korea.
b Department of Ophthalmology, Institute, of Health Sciences, School of Medicine , Gyeongsang National University , Jinju , Gyeongnam , Republic of Korea.
Curr Eye Res. 2017 Dec;42(12):1650-1658. doi: 10.1080/02713683.2017.1344713. Epub 2017 Oct 6.
Ischemia/reperfusion (I/R) injury induces apoptosis in retinal ganglion cells (RGCs). Resveratrol (Res) is a potent natural antioxidant with beneficial effects in many ocular diseases, such as age-related macular degeneration, diabetic retinopathy, and glaucoma. Because caspase-3 expression is highly correlated with activation of the apoptotic pathway, the present study aimed to determine whether Res regulates the expression of caspase-3 using an I/R retinal injury mouse model.
Male C57BL/6J mice were injected with Res for 2 consecutive days before I/R retinal injury. I/R retinal injury was induced by increasing the intraocular pressure for 1 h. Res was then injected for 3 consecutive days. Changes in retinal morphology were monitored for 3 days after injury by histochemistry using hematoxylin and eosin staining. mRNAs and proteins were extracted 2 days after injury. The expression levels of caspase-8 and caspase-3 mRNA and protein were determined using reverse-transcriptase polymerase chain reaction (RT-PCR) and western blot analyses.
I/R injury induced declines in retinal thickness and number of RGCs during 5 days after injury. Caspase-8 and caspase-3 mRNA and protein activation increased. Res treatment reduced the significant loss of retinal morphology and downregulated the expression of mRNA and activation of caspase-8 and caspase-3 protein.
The observed changes in retinal morphology suggest that I/R injury promotes retinal degeneration. Increased expression of caspase-8 and caspase-3 mRNA indicates apoptosis activation. Res, however, suppresses apoptosis via downregulation of caspase-8 and caspase-3 expression.
缺血/再灌注（I/R）损伤可诱导视网膜神经节细胞（RGCs）凋亡。白藜芦醇（Res）是一种有效的天然抗氧化剂，对许多眼部疾病具有有益作用，如年龄相关性黄斑变性、糖尿病视网膜病变和青光眼。由于半胱天冬酶-3的表达与凋亡途径的激活高度相关，本研究旨在使用I/R视网膜损伤小鼠模型确定Res是否调节半胱天冬酶-3的表达。
雄性C57BL/6J小鼠在I/R视网膜损伤前连续2天注射Res。通过升高眼压1小时诱导I/R视网膜损伤。然后连续3天注射Res。损伤后3天，使用苏木精和伊红染色的组织化学方法监测视网膜形态变化。损伤后2天提取mRNA和蛋白质。使用逆转录聚合酶链反应（RT-PCR）和蛋白质印迹分析确定半胱天冬酶-8和半胱天冬酶-3 mRNA及蛋白质的表达水平。
I/R损伤导致损伤后5天内视网膜厚度和RGCs数量下降。半胱天冬酶-8和半胱天冬酶-3 mRNA及蛋白质激活增加。Res治疗减少了视网膜形态的显著损失，并下调了mRNA的表达以及半胱天冬酶-8和半胱天冬酶-3蛋白质的激活。
观察到的视网膜形态变化表明I/R损伤促进视网膜变性。半胱天冬酶-8和半胱天冬酶-3 mRNA表达增加表明凋亡激活。然而，Res通过下调半胱天冬酶-8和半胱天冬酶-3的表达来抑制凋亡。
