NF-κB participates in hepcidin up-regulation induced by iron overload in HH4 hepatocytes
LI Shi-wei1,2, LI Xiang3, GUAN Feng1,2
1. Key Laboratory of Carbohydrate Chemistry & Biotechnology, Ministry of Education, Wuxi 214122, China;
2. School of Biotechnology, Wuxi 214122, China;
3. Wuxi Medical School, Jiangnan University, Wuxi 214122, China
AIM: To study the effects of nuclear factor kappa B (NF-κB) on human hepcidin expression in ferric ammonium citrate (FAC)-induced HH4 hepatocytes.METHODS: Non-transformed HH4 cells were exposed to FAC at concentrations of 0.1, 1, 5 and 10 mmol/L for 48 h. The expression of iron regulatory gene hepcidin was determined by semi-quantitative RT-PCR. The effects of NF-κB on hepcidin transcriptional activity were detected using chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA) and dual-luciferase reporter assay system, combined with the inhibition experiments of intracellular NF-κB activity.RESULTS: FAC at concentrations of 5 mmol/L and 10 mmol/L significantly enhanced the expression of hepcidin. The results of ChIP and EMSA showed the binding of NF-κB to the upstream of hepcidin promoter. Treatment with NF-κB inhibitor BAY 11-7082 attenuated hepcidin expression. The luciferase activity in the cells transfected with recombinant luciferase reporter plasmid was obviously higher than that in control group.CONCLUSION: NF-κB is the transcription factor that contributes to hepcidin expression in iron overload-induced HH4 cells.
Xu Q, Kanthasamy A, Jin H, et al. Hepcidin plays a key role in 6-OHDA induced iron overload and apoptotic cell death in a cell culture model of Parkinson's disease[J]. FASEB J, 2014, 28(1 Suppl):1038.
[2]
Viatte L, Vaulont S. Hepcidin, the iron watcher[J]. Biochimie, 2009, 91(10):1223-1228.
[3]
Corradini E, Rozier M, Meynard D, et al. Iron regulation of hepcidin despite attenuated Smad1,5,8 signaling in mice without transferrin receptor 2 or Hfe [J]. Gastroenterology, 2011, 141(5):1907-1914.
[4]
Nemeth E, Tuttle MS, Powelson J, et al. Hepcidin regulates cellular iron efflux by binding to ferroportin and inducing its internalization[J]. Science, 2004, 306(5704):2090-2093.
[5]
Ganz T. Hepcidin, a key regulator of iron metabolism and mediator of anemia of inflammation[J]. Blood, 2003, 102(3):783-788.
[6]
Papanikolaou G, Tzilianos M, Christakis JI, et al. Hepcidin in iron overload disorders[J]. Blood, 2005, 105(10):4103-4105.
[7]
Lin L, Valore EV, Nemeth E, et al. Iron transferrin regulates hepcidin synthesis in primary hepatocyte culture through hemojuvelin and BMP2/4 [J]. Blood, 2007, 110(6):2182-2189.
[8]
Bloomer SA, Kregel KC, Brown KE. Heat stress stimulates hepcidin mRNA expression and C/EBPα protein expression in aged rodent liver[J]. Arch Gerontol Geriatr, 2014, 58(1):145-152.
[9]
De Domenico I, Ward DM, Kaplan J. Regulation of iron acquisition and storage:consequences for iron-linked disorders[J]. Nat Rev Mol Cell Biol, 2008, 9(1):72-81.
