title: Mitochondrial Profile and Responses to TGF-β Ligands in Keratoconus.
abstract: Keratoconus (KC) is a complex corneal dystrophy with multifactorial etiology. Previous studies have shown evidence of mitochondrial abnormalities in KC; however, the exact cause of these abnormalities remains unknown. The aim of this study was to identify if transforming growth factor-β (TGF-β) isoforms play a role in the regulation of mitochondrial proteins in human KC cells (HKC).
  
  
  
  Human corneal fibroblasts (HCF) and HKC were isolated and cultured for 4 weeks in three different conditions: (a)
  
  
  
  MEM + 10%FBS, (b) MEM + 10%FBS + TGF-β1 and (c) MEM + 10%FBS + TGF-β3. All samples were processed for mitochondrial damage analysis using real-time PCR.
  
  
  
  We quantified and analyzed 84 mitochondrial and five housekeeping genes in HCFs and HKCs. Our data showed that when TGF-β1 and/or TGF-β3 were compared with control in HCFs, nine genes were significantly different; however, no genes were significantly regulated by the TGF-β isoforms in HKCs. Significant differences were also seen in seven genes when HFCs were compared with HKCs, in all three conditions.
  
  
  
  Overall, our data support the growing consensus that mitochondrial dysfunction is a key player in KC disease. These in vitro data show clear links between mitochondrial function and TGF-β isoforms, with TGF-β1 severely disrupting KC-mitochondrial function, while TGF-β3 maintained it, thus suggesting that TGF-β may play a role in KC-disease treatment.
authors.affiliation: a Department of Ophthalmology/Dean McGee Eye Institute , University of Oklahoma Health Sciences Center , Oklahoma City , OK , USA.
authors.forename: Akhee
authors.initials: A
authors.lastname: Sarker-Nag
authors.affiliation: b Schepens Eye Research Institute/MEE and Department of Ophthalmology , Harvard Medical School , Boston , MA , USA.
authors.forename: Audrey E K
authors.initials: AE
authors.lastname: Hutcheon
authors.affiliation: a Department of Ophthalmology/Dean McGee Eye Institute , University of Oklahoma Health Sciences Center , Oklahoma City , OK , USA.|c Department of Cell Biology , University of Oklahoma Health Sciences Center , Oklahoma City , OK , USA.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Karamichos
mesh_terms: D002478:Cells, Cultured; D003315:Cornea / Q000378:metabolism / Q000473:pathology; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007640:Keratoconus / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008024:Ligands; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012313:RNA / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D008024:Ligands; D016212:Transforming Growth Factor beta; D012313:RNA
keywords: Cornea; keratoconus; mitochondria; mitochondrial dysfunction; transforming growth factor-β