Abstract

Mn²⁺ is a minor nutrient, but is essential for numerous enzymatic activities and thus, for many cellular functions. However, its physiological roles and toxicity remain to be elucidated. In this study, we assessed the pharmacological potential and toxicity of Mn²⁺ in the immune system by examining the effects of Mn²⁺ on interleukin-2 (IL-2) production by Jurkat T-cells. Mn²⁺ at 0.1-1 mM did not significantly induce IL-2 production, whereas phorbol 12-myristate 13-acetate (PMA) at 1 μM slightly induced IL-2 production. Interestingly, Mn²⁺ at 0.3-0.7 mM promoted PMA-induced IL-2 production in a dose-dependent manner. A reporter gene assay revealed that Mn²⁺ promoted the activity of AP-1 (activator protein-1, a complex of c-Fos and c-Jun) in the presence of PMA. Western blot analysis showed that Mn²⁺ promoted the activation of JNK2 (c-Jun N-terminal kinase 2) and p38 MAPK (mitogen-activated protein kinase), which are both activators of AP-1, and upregulated the production of c-Fos and c-Jun within 4h in the presence of PMA. These results suggest that Mn²⁺ promotes PMA-induced IL-2 production by inducing the production and activation of AP-1, at least in part.

Links

Publisher Full Text

Authors

Tanaka S, Masuda Y, Honma C, Hosaka K, Takahashi K, Kubohara Y

Institution

Department of Health and Nutrition, Faculty of Health and Welfare, Takasaki University of Health and Welfare, Takasaki 370-0033, Japan.

Source

Toxicology letters 211:3 2012 Jun 20 pg 312-8

MeSH

Blotting, Western
Calcineurin
Cell Survival
Chlorides
Humans
Interleukin-2
Jurkat Cells
Luciferases
Manganese Compounds
Mitogen-Activated Protein Kinases
NF-kappa B
NFATC Transcription Factors
Proto-Oncogene Proteins c-fos
Proto-Oncogene Proteins c-jun
RNA, Messenger
Real-Time Polymerase Chain Reaction
Tetradecanoylphorbol Acetate
Transcription Factor AP-1
Transcriptional Activation

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22561169