title: Up-Regulation of PKM2 Relates to Retinal Ganglion Cell Apoptosis After Light-Induced Retinal Damage in Adult Rats.
abstract: Pyruvate kinase isozyme type M2 (PKM2), a key glycolytic enzyme, which is involved in ATP generation and pyruvate production, participates in tumor metabolism, growth, and other multiple cellular processes. However, one attractive biological function of PKM2 is that it translocates to the nucleus and induces cell apoptosis. Recently, increased PKM2 has been found in age-related macular degeneration (AMD), but little is known regarding its function in the AMD pathophysiology. To investigate whether PKM2 participated in retinal degeneration, we performed a light-induced retinal damage model in adult rats. Western blot and immunohistochemistry analysis showed a significant up-regulation of PKM2 in retinal ganglion cells (RGCs) layer (GCL) after light exposure. Immunofluorescent labeling indicated that PKM2 located mainly in RGCs. Co-localization of PKM2 and active caspase-3 as well as TUNEL in RGCs suggested that PKM2 might participate in RGC apoptosis. In addition, the expression patterns of cyclin D1 and phosphorylated extracellular signal-regulated kinase (p-ERK) were parallel with that of PKM2. Furthermore, PKM2, cyclin D1, and active caspase-3 protein expression decreased by intravitreal injection of U0126, a highly selective inhibitor of MAPK/ERK kinase. Collectively, we hypothesized that PKM2 might participate in RGC apoptosis after light-induced retinal damage medicated by p-ERK through cycle re-entry mechanism.
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Manhui
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Rongrong
authors.initials: R
authors.lastname: Zhu
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Bai
authors.initials: B
authors.lastname: Qin
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Hongda
authors.initials: H
authors.lastname: Fang
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China.
authors.forename: Ming
authors.initials: M
authors.lastname: Dai
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China. sangam@ntu.edu.cn.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China. sangam@ntu.edu.cn.
authors.forename: Aimin
authors.initials: A
authors.lastname: Sang
authors.affiliation: Department of Pathogen Biology, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China. ntlxj0305@163.com.|Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College, Nantong University, Nantong, 226001, Jiangsu, People's Republic of China. ntlxj0305@163.com.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Liu
mesh_terms: D000367:Age Factors; D000818:Animals; D017209:Apoptosis; D002352:Carrier Proteins / Q000096:biosynthesis*; D058449:Intravitreal Injections; D008027:Light / Q000009:adverse effects*; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism / Q000473:pathology; D012165:Retinal Ganglion Cells / Q000378:metabolism* / Q000473:pathology*; D013963:Thyroid Hormones / Q000096:biosynthesis*; D015854:Up-Regulation / Q000502:physiology*; D000097810:Thyroid Hormone-Binding Proteins
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D013963:Thyroid Hormones; D000097810:Thyroid Hormone-Binding Proteins
keywords: Apoptosis; Cyclin D1; ERK; Light-induced retinal damage; PKM2; RGCs; Rat