Copper-induced ferroportin-1 expression in J774 macrophages is associated with increased iron efflux

J Chung, DJ Haile… - Proceedings of the …, 2004 - National Acad Sciences
J Chung, DJ Haile, M Wessling-Resnick
Proceedings of the National Academy of Sciences, 2004National Acad Sciences
Copper is known to play a role in iron recycling from macrophages. To examine whether
cellular copper status affects expression of the iron exporter ferroportin-1 (FPN1), J774
macrophage cells were exposed to 10–100 μM CuSO4 for up to 20 h. Copper treatment
significantly increased FPN1 mRNA in a dose-and time-dependent manner. After 20 h, 100
μM CuSO4 up-regulated FPN1 transcript levels≈ 13-fold compared to untreated controls.
Induction was detected 8 h after copper treatment was initiated and markedly increased …
Copper is known to play a role in iron recycling from macrophages. To examine whether cellular copper status affects expression of the iron exporter ferroportin-1 (FPN1), J774 macrophage cells were exposed to 10–100 μM CuSO4 for up to 20 h. Copper treatment significantly increased FPN1 mRNA in a dose- and time-dependent manner. After 20 h, 100 μM CuSO4 up-regulated FPN1 transcript levels ≈13-fold compared to untreated controls. Induction was detected 8 h after copper treatment was initiated and markedly increased thereafter. A corresponding increase in FPN1 protein levels was observed upon copper treatment. Induction of J774 cell FPN1 expression by copper was also associated with a dose-dependent increase in 59Fe release after erythrophagocytosis of labeled red blood cells. Thus, a previously uncharacterized role for copper in the regulation of macrophage iron recycling is suggested by the induction of FPN1 gene expression and iron efflux by this metal.
National Acad Sciences