γ-tocotrienol reduces squalene hydroperoxide-induced inflammatory responses in HaCaT keratinocytes

Kiyotaka Nakagawa, Akira Shibata, Toru Maruko, Phumon Sookwong, Tsuyoshi Tsuduki, Kayoko Kawakami, Hiroshi Nishida, Teruo Miyazawa

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

Squalene hydroperoxide (SQ-OOH), the primary peroxidation product of squalene (SQ), accumulates at the surface of sunlight-exposed human skin. There are however only a few studies on the pathogenic actions (i.e., inflammatory stimuli) of SQ-OOH. Here, we evaluated whether SQ-OOH induced inflammatory responses in immortalized human keratinocytes (HaCaT). We found that SQ-OOH caused an increase in the expression of inflammatory genes such as the interleukins as well as cyclooxygenase-2 (COX-2). In concordance with the upregulation of COX-2 mRNA, SQ-OOH enhanced reactive oxygen species generation, nuclear factor kappa B activation, COX-2 protein expression, and prostaglandin E2 production. Therefore, the pro-inflammatory effects of SQ-OOH may be mediated in part via COX-2. On the other hand, γ-tocotrienol (γ-T3, an unsaturated form of vitamin E) was found to ameliorate the SQ-OOH actions. These results suggest that SQ-OOH induces inflammatory responses in HaCaT, implying that SQ-OOH plays an important role in inflammatory skin disorders. As a preventive strategy, inflammation could be reduced via the use of γ-T3.

Original languageEnglish
Pages (from-to)833-841
Number of pages9
JournalLipids
Volume45
Issue number9
DOIs
Publication statusPublished - 2010 Sep

Keywords

  • Cyclooxygenase-2
  • Inflammatory skin diseases
  • Squalene hydroperoxide
  • γ-Tocotrienol

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Cell Biology

Fingerprint Dive into the research topics of 'γ-tocotrienol reduces squalene hydroperoxide-induced inflammatory responses in HaCaT keratinocytes'. Together they form a unique fingerprint.

Cite this