Different Characteristics of Hepcidin Expression in IL-6+/+ and IL-6−/− Neurons and Astrocytes Treated with Lipopolysaccharides
A region-specific regulation of inflammation on the expression hepcidin in the brain has been demonstrated, however, it remains unknown whether there is also a cell-specific regulation of inflammation on hepcidin in the brain. Here, we investigated the effects of lipopolysaccharides (LPS) on the expression of hepcidin mRNA and also the expression of IL-6 mRNA, the phosphorylation of STAT3 and the expression of ferroportin 1 (Fpn1) and ferritin light chain (Ft-L) proteins in neurons and astrocytes obtained from wild type (IL-6+/+) and IL-6 knockout (IL-6−/−) mice. We demonstrated that the responses of the expression of hepcidin and IL-6 mRNAs, the phosphorylation of STAT3, and the expression of Fpn1 protein to LPS in IL-6+/+ astrocytes and also the responses of the expression of hepcidin mRNA, the phosphorylation of STAT3 and the expression of Fpn1 protein to IL-6 in IL-6−/− astrocytes were much stronger than those in IL-6+/+ and IL-6−/− neurons. A significant increase in Ft-L was found in LPS-treated IL-6+/+ and IL-6-treated IL-6−/− astrocytes, but not in LPS-treated IL-6+/+ and IL-6-treated IL-6−/− neurons. Our findings provide in vitro evidence for the existence of a cell-specific regulation of LPS on the expression of hepcidin and also Ft-L in the brain.
KeywordsNeuron and astrocyte Lipopolysaccharides (LPS) Hepcidin and ferroportin 1 (Fpn1) Ferritin light chain (Ft-L) and cell iron content IL-6/STAT3 pathway
Ferritin light chain
Signal transducer and activator of transcription 3
The studies in our laboratories were supported by National Natural Science Foundation of China (31330035, 31571195), and the National Basic Research Program of China (973) (2014CB541604).
GZ, YXB and ZMQ conceived, organized and supervised the study; JM, FLZ and YS performed the experiments; YXB and GZ contributed to the analysis of data; ZMQ prepared and wrote the manuscript. All authors read and approved the final edition of the manuscript.
Compliance with Ethical Standards
Conflict of interest
The authors who have taken part in this study declared that they do not have anything to disclose regarding funding or conflict of interest with respect to this manuscript.
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