Elevation of intracellular Ca 2+ level by triclosan in rat thymic lymphocytes

Increase in membrane Ca 2+ permeability and induction of intracellular Ca 2+ release

Ikumi Tamura, Minoru Saito, Yumiko Nishimura, Masaya Satoh, Hiroshi Yamamoto, Yasuo Oyama

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Triclosan is an antibacterial agent used in household items and personal care products. Because wild animals and humans can harbor this compound in their systems, the toxic effects of triclosan are a possibility and are suspected. Therefore, we examined the effects of triclosan on intracellular Ca 2+ concentration in rat thymocytes by cytometric techniques using fluorescent probes. Triclosan doses of 1-10μM significantly increased the intensity of Ca 2+-detecting Fluo-3 fluorescence, indicating an increase in intracellular Ca 2+ concentrations. The augmentation of Fluo-3 fluorescence became more profound in a dosedependent manner after the addition of an external source of Ca 2+. Conversely, the removal of external Ca 2+ greatly attenuated the triclosan-induced augmentation of Fluo-3 fluorescence. These results suggest that triclosan treatment allows external Ca 2+ to pass through cell membranes. This phenomenon was not specific for Ca 2+ because externalMn 2+ quenched the triclosan-induced augmentation of Fluo-3 fluorescence, indicating that triclosan can also mediate Mn 2+ permeation across membranes. Therefore, these results suggest that triclosan increases membrane permeability to divalent metal cations. Furthermore, triclosan induces Ca 2+ release from intracellular stores because the Fluo-3 fluorescence inten-sity still increased slightly after triclosan treatment, even under conditions free from external Ca 2+. Additionally, triclosan did not increase the intensity of Fluo-3 fluorescence when Ca 2+ was depleted from intracellular Ca 2+ stores by A23187 under the external Ca 2+-free condition. Taken together, these data suggest that micromolar concentrations of triclosan affect intracellular Ca 2+ homeostasis in thymocytes, possibly resulting in cellular malfunction.

Original languageEnglish
Pages (from-to)540-546
Number of pages7
JournalJournal of Health Science
Volume57
Issue number6
Publication statusPublished - 2011
Externally publishedYes

Fingerprint

Triclosan
Lymphocytes
Rats
Permeability
Membranes
Fluorescence
Thymocytes
Wild Animals
Poisons
Divalent Cations
Calcimycin
Cell membranes
Ports and harbors
Fluorescent Dyes
Permeation

Keywords

  • Ca
  • Fluo-3
  • Thymocyte
  • Triclosan

ASJC Scopus subject areas

  • Toxicology
  • Health, Toxicology and Mutagenesis

Cite this

Elevation of intracellular Ca 2+ level by triclosan in rat thymic lymphocytes : Increase in membrane Ca 2+ permeability and induction of intracellular Ca 2+ release. / Tamura, Ikumi; Saito, Minoru; Nishimura, Yumiko; Satoh, Masaya; Yamamoto, Hiroshi; Oyama, Yasuo.

In: Journal of Health Science, Vol. 57, No. 6, 2011, p. 540-546.

Research output: Contribution to journalArticle

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