Premium
Hg 2+ and Ni 2+ alter induction of heat shock protein‐72 in THP‐1 human monocytes
Author(s) -
Noda M.,
Wataha J. C.,
Lewis J. B.,
Lockwood P. E.,
Komatsu H.,
Sano H.
Publication year - 2003
Publication title -
journal of biomedical materials research part a
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.849
H-Index - 150
eISSN - 1552-4965
pISSN - 1549-3296
DOI - 10.1002/jbm.a.10100
Subject(s) - heat shock protein , hsp70 , glutathione , materials science , monocyte , heat shock , metal , oxidative stress , thp1 cell line , biophysics , microbiology and biotechnology , biochemistry , biology , cell culture , immunology , metallurgy , enzyme , genetics , gene
The biological liabilities that result from the release of metal ions from biomedical alloys, particularly Ni 2+ and Hg 2+ , continue to be a concern. Heat‐shock proteins (HSP) are a class of molecular chaperones that may be induced under conditions of cellular stress, including oxidative stress. Our hypothesis was that because Hg 2+ and Ni 2+ alter other cellular stress responses such as glutathione levels and cytokine secretion, these metal ions may alter HSP induction in monocytes, which are key cells in the response of tissues to biomedical alloys. THP‐1 monocytes were exposed to sublethal concentrations of Hg 2+ or Ni 2+ for 1 h with or without heat stress (43°C), then allowed to recover at 37°C for 2–6 h. HSP72 was measured using immunoblotting with phosphorimage quantification. Hg 2+ exposures of 2–10 μmol/L induced HSP72 without heat stress. With heat stress, HSP72 levels were altered by Hg 2+ versus heat stress alone. The response depended on the concentration of Hg 2+ and the recovery time. Hg 2+ at 10 μmol/L caused uniformly lower HSP72 levels. Ni 2+ exposures of 20–100 μmol/L did not induce HSP72 without heat stress, but significantly altered heat‐induced HSP72 expression, with a significant increase in expression over heat alone at 40 and 100 μmol/L. Results from the current study support the hypothesis that these metal ions can, at concentrations relevant to those released from biomedical alloys, modulate HSP expression in human monocytes. The modulation of HSP expression indicates an early sign of cellular stress that may be important to the overall biological response to biomedical alloys containing and releasing these metal ions. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 240–245, 2003