Antifibrotic effects of tocotrienols on human Tenon’s fibroblasts

  • Christoph Tappeiner
  • Alexander Meyenberg
  • David Goldblum
  • Daniel Mojon
  • Jean-Marc Zingg
  • Kalanithi Nesaretnam
  • Monika Kilchenmann
  • Beatrice E. Frueh
Glaucoma

Abstract

Purpose

To compare the antifibrotic effect of vitamin E isoforms α-, γ-, and δ-tocotrienol on human Tenon’s fibroblasts (hTf) to the antimetabolite mitomycin C.

Methods

Antifibrotic effects of α- (40, 60, 80, 100, and 120 μM), γ- (10, 20, 30, and 40 μM) and δ-tocotrienol (10, 20, 30, and 40 μM) on hTf cultures were evaluated by performing proliferation, migration and collagen synthesis assays. Whereas for vitamin E the exposure time was set to 7 days to mimic subconjunctival application, cultures were exposed only 5 min to mitomycin C 100 μg/ml to mimic intraoperative administration. Cell morphology (phase contrast microscopy) as an assessment for cytotoxicity and cell density by measuring DNA content in a fluorometric assay to determine proliferation inhibition was performed on day 0, 4, and 7. Migration ability and collagen synthesis of fibroblasts were measured.

Results

All tested tocotrienol isoforms were able to significantly inhibit hTf proliferation in a dose-dependent manner (maximal inhibitory effect without relevant morphological changes at day 4 for α-tocotrienol 80 μM with 36.7% and at day 7 for α-tocotrienol 80 μM with 42.6% compared to control). Degenerative cell changes were observed in cultures with concentrations above 80 μM for α- and above 30 μM for γ- and δ-tocotrienol. The highest collagen synthesis inhibition has been found with 80 µM α-tocotrienol (62.4%) and no significant inhibition for mitomycin C (2.5%). Migration ability was significantly reduced in cultures exposed to 80 µM α- and 30 µM γ-tocotrienol (inhibition of 82.2% and 79.5%, respectively, compared to control) and also after mitomycin C treatment (60.0%). Complete growth inhibition without significant degenerative cell changes could only be achieved with mitomycin C.

Conclusion

In vitro, all tested tocotrienol isoforms were able to inhibit proliferation, migration and collagen synthesis of human Tenon’s fibroblasts and therefore may have the potential as an anti-scarring agent in filtrating glaucoma surgery.

Keywords

Vitamin E Tocotrienol Antifibrotic effect Tenon’s fibroblast Filtrating glaucoma surgery Mitomycin C 

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Christoph Tappeiner
    • 1
  • Alexander Meyenberg
    • 1
  • David Goldblum
    • 2
  • Daniel Mojon
    • 3
  • Jean-Marc Zingg
    • 4
  • Kalanithi Nesaretnam
    • 5
  • Monika Kilchenmann
    • 1
  • Beatrice E. Frueh
    • 1
  1. 1.Department of Ophthalmology, InselspitalUniversity of BernBernSwitzerland
  2. 2.Department of OphthalmologyUniversity Hospital Basel, University BaselBaselSwitzerland
  3. 3.Department of OphthalmologyKantonsspitalSt. GallenSwitzerland
  4. 4.Institute of Biochemistry and Molecular MedicineUniversity of BernBernSwitzerland
  5. 5.Malaysian Palm Oil BoardKuala LumpurMalaysia

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