title: Heme oxygenase-1 (HO-1) protects human lens epithelial cells (SRA01/04) against hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis.
abstract: This study aimed to investigate the protective role of heme oxygenase-1 (HO-1) in H2O2-induced oxidative stress and apoptosis in human lens epithelial cells (hLEC; SRA01/04).
  
  
  
  SRA01/04 cells were exposed to a hydrogen peroxide (H2O2) concentration gradient and inducers of HO-1 such as cobalt protoporphyrin (CoPP) and zinc protoporphyrin (ZnPP), respectively. In addition, an RNA silencing experiment was conducted to investigate the HO-1 function in this study. A Cell Counting Kit-8 (CCK-8) assay was used to measure cell viability. Western blot and ELISA were used to detect the level of HO-1 expression. In our study, hLECs were exposed to 400 μM hydrogen peroxide (H2O2) for 24 h with or without pretreatment with 10μΜ CoPP or 10μΜ ZnPP, respectively. Double immunofluorescence staining was used for cell identification and the qualitative expression of HO-1. Expression of HO-1 was monitored using Western blot and ELISA. Intracellular reactive oxygen species (ROS) were detected by flow cytometry analyses; commercial enzymatic kits were used to measure the levels of glutathione (GSH), as well as superoxide dismutase (SOD). The proportion of cell apoptosis was quantified by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. The expression of caspase family (-8, -3) proteins was measured by Western blot analysis.
  
  
  
  HO-1 significantly restored the cell viability under H2O2 injury via reducing the generation of ROS and increasing the levels of SOD and GSH activity. Moreover, HO-1 also inhibited H2O2-induced caspase-8 and caspase-3 proteins, thus significantly reducing the apoptosis of SRA01/04. An RNA silencing experiment demonstrated the increased resistance of LECs to oxidative stress specifically for increased levels of HO-1.
  
  
  
  These findings suggested that HO-1 protects human lens epithelial cells from H2O2-induced oxidant stress by upregulating antioxidant enzyme activity, reducing ROS generation, and thus inhibiting caspase family-dependent apoptosis.
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Tianju
authors.initials: T
authors.lastname: Ma
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Tingjun
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, The Tianjin Eye Hospital, Tianjin, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Ye
authors.affiliation: Department of Burn and Plastic Surgery, Peking University First Hospital, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhai
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Jia
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Wenqian
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China; Medical School, Nankai University, Tianjin, China.
authors.forename: Ang
authors.initials: A
authors.lastname: Sun
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China. Electronic address: weishihui706@hotmail.com.
authors.forename: Shihui
authors.initials: S
authors.lastname: Wei
authors.affiliation: Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China. Electronic address: zhaohuili650@hotmail.com.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Li
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D004847:Epithelial Cells / Q000378:metabolism*; D005981:Glutathione Synthase / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000502:physiology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007908:Lens, Crystalline / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D006861:Hydrogen Peroxide; D051547:Heme Oxygenase-1; D013482:Superoxide Dismutase; D053148:Caspase 3; D053181:Caspase 8; D005981:Glutathione Synthase
keywords: Antioxidation; Apoptosis; Cataract; Heme Oxygenase-1 (HO-1); Human lens epithelial cells (SRA01/04); Oxidative stress