Planta Med 2010; 76(9): 869-875
DOI: 10.1055/s-0029-1240812
Pharmacology
Original Papers
© Georg Thieme Verlag KG Stuttgart · New York

Alpha-tocopherol Modulates Hydrogen Peroxide-Induced DNA Damage and Telomere Shortening of Human Skin Fibroblasts Derived from Differently Aged Individuals

Suzana Makpol1 , Azalina Zainuddin1 , Norhazira Abdul Rahim1 , Yasmin Anum Mohd Yusof1 , Wan Zurinah Wan Ngah1
  • 1Department of Biochemistry, Faculty of Medicine, National University of Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
Further Information

Publication History

received June 8, 2009 revised Dec. 17, 2009

accepted Dec. 29, 2009

Publication Date:
28 January 2010 (online)

Abstract

Antioxidants such as vitamin E may act differently on skin cells depending on the age of the skin and the level of oxidative damage induced. The effects of alpha-tocopherol (ATF) on H2O2-induced DNA damage and telomere shortening of normal human skin fibroblast cells derived from young and old individual donors were determined. Fibroblasts were divided into five groups; untreated control, H2O2-induced oxidative stress, alpha-tocopherol treatment, and pre- and post-treatment with alpha-tocopherol for H2O2-induced oxidative stress. Our results showed that H2O2-induced oxidative stress increased DNA damage, shortened the telomere length and reduced the telomerase activity (p < 0.05) in fibroblasts obtained from young and old donors. Pre- and post-treatment with alpha-tocopherol protected against H2O2-induced DNA damage in fibroblasts obtained from young individuals (p = 0.005; p = 0.01, respectively). However, in fibroblasts obtained from old individuals, similar protective effects were only seen in cells pretreated with alpha-tocopherol (p = 0.05) but not in the post-treated cells. Protection against H2O2-induced telomere shortening was observed in fibroblasts obtained from both young and old donors which were pre-treated with alpha-tocopherol (p = 0.009; p = 0.008, respectively). However, similar protective effects against telomere shortening in fibroblasts obtained from both young and old donors were not observed in the post-treated fibroblasts. Protection against H2O2-induced telomerase activity loss was observed only in fibroblasts obtained from old donors which were pretreated with alpha-tocopherol (p = 0.04) but not in fibroblasts obtained from young donors. Similar protective effects against telomerase activity loss in fibroblasts obtained from both young and old donors were not observed in the post-treated fibroblasts. In conclusion, alpha-tocopherol protected against H2O2-induced telomere shortening by restoring the telomerase activity. It also modulated H2O2-induced DNA damage and this modulation was affected by donor age.

References

Assoc. Prof. Dr. Suzana Makpol

Department of Biochemistry
Faculty of Medicine
National University of Malaysia

Jalan Raja Muda Abd. Aziz

50300 Kuala Lumpur

Malaysia

Phone: + 60 3 92 89 72 96 and + 60 3 92 89 72 22

Fax: + 60 3 26 93 80 37

Email: suzanamakpol@yahoo.com

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