title: Mitochondria-targeted peptide MTP-131 alleviates mitochondrial dysfunction and oxidative damage in human trabecular meshwork cells.
abstract: OBJECTIVE
  To investigate the antioxidative ability of a novel mitochondria-targeted peptide MTP-131 in immortalized human trabecular meshwork (iHTM) and glaucomatous human trabecular meshwork (GTM(3)) cell lines.
  
  
  METHODS
  Cultured iHTM and GTM(3) cells were pretreated with MTP-131 for 1 hour, and sustained oxidative stress was induced by subjecting TM cells to 200 μM hydrogen peroxide (H(2)O(2)) for 24 hours. Untreated cells and cells incubated with H(2)O(2) alone were used as controls. Lactate dehydrogenase (LDH) assay was used to determine cell viability. Changes of mitochondrial membrane potential (ΔΨm) and generation of intracellular reactive oxygen species (ROS) were analyzed by flow cytometry and confocal microscopy. Activation of caspase 3 was quantified by Western blotting, and apoptosis was measured by flow cytometry. Release of cytochrome c and changes in cytoskeleton were analyzed by confocal microscopy. Data were analyzed with commercial data analysis software and P < 0.05 was considered to be statistically significant.
  
  
  RESULTS
  In both iHTM and GTM(3) cells, decrease of ΔΨm and elevation of intracellular ROS were detected after sustained oxidative stress induced by H(2)O(2). When cells were pretreated with MTP-131, the H(2)O(2)-induced mitochondrial depolarization was prevented; intracellular ROS, LDH release, and apoptosis were significantly decreased; release of cytochrome c from mitochondria to cytoplasm and activation of caspase 3 were inhibited. In addition, cytoskeleton changes caused by H(2)O(2) were also alleviated by MTP-131.
  
  
  CONCLUSIONS
  Mitochondria-targeted peptide MTP-131 could prevent both iHTM and GTM(3) cells from sustained oxidative stress induced by H(2)O(2).
authors.affiliation: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Bingqian
authors.initials: B
authors.lastname: Liu
authors.forename: Qianying
authors.initials: Q
authors.lastname: Gao
authors.forename: Yehong
authors.initials: Y
authors.lastname: Zhuo
authors.forename: Jian
authors.initials: J
authors.lastname: Ge
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D028361:Mitochondrial Diseases / Q000378:metabolism / Q000517:prevention & control*; D009842:Oligopeptides / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014129:Trabecular Meshwork / Q000187:drug effects* / Q000378:metabolism
chemical_list: D017304:Annexin A5; D009842:Oligopeptides; D017382:Reactive Oxygen Species; C506540:arginyl-2,'6'-dimethyltyrosyl-lysyl-phenylalaninamide; D045304:Cytochromes c; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; D053148:Caspase 3