The effects of blunt snout bream (Megalobrama amblycephala) IL-6 trans-signaling on immunity and iron metabolism via JAK/STAT3 pathway

Jixiu Wang; Qianhui Sun; Guowen Wang; Huanling Wang; Hong Liu

doi:10.1016/j.dci.2022.104372

The effects of blunt snout bream (Megalobrama amblycephala) IL-6 trans-signaling on immunity and iron metabolism via JAK/STAT3 pathway

Dev Comp Immunol. 2022 Jun:131:104372. doi: 10.1016/j.dci.2022.104372. Epub 2022 Feb 23.

Authors

Jixiu Wang¹, Qianhui Sun¹, Guowen Wang¹, Huanling Wang¹, Hong Liu²

Affiliations

¹ College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affair / Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China.
² College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affair / Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China. Electronic address: liuhong59@mail.hzau.edu.cn.

PMID: 35217123
DOI: 10.1016/j.dci.2022.104372

Abstract

Interleukin-6 (IL-6) is a pleiotropic inflammatory cytokine, which plays a dual role in mammalian inflammation through both classical signaling (IL-6 binds to IL-6 receptor/IL-6R) and trans-signaling (IL-6 binds to soluble IL-6R). However, the function of IL-6, especially the regulatory mechanism of IL-6 trans-signaling in immunity and iron metabolism remains largely unclear in teleost. Here, L8824 cells (Ctenopharyngodon idella hepatic cells) were stimulated with blunt snout bream (Megalobrama amblycephala) IL-6 combination with sIL-6R protein (rmaIL-6+rmasIL-6R/maIL-6 trans-signaling) or STAT3 inhibitor (c188-9), and RNA-sequencing, global transcriptional analyses. The enrichment analysis of GO and KEGG showed that maIL-6 trans-signaling is mainly involved in stress and inflammation response, and the activation of STAT3 is mainly related to cell proliferation, apoptosis and immune regulation. Furthermore, after treated L8824 cells with JAK2 inhibitors, it was found that the induction of IL-6 trans-signaling on the selected immune-related genes could be inhibited. These results implied that in early stage after rmaIL-6+rmasIL-6R treatment, the maIL-6 trans-signaling played an important role in the immune regulation through the JAK2/STAT3 pathway. By extending the rmaIL-6+rmasIL-6R treatment time, it was found that maIL-6 trans-signaling could promote the expression of iron metabolism related genes (ft, tf, tfr1, hamp and fpn1) in L8824 cells, indicating that maIL-6 trans-signaling may be involved in iron metabolism in the non-acute immune phase. Finally, after treated L8824 cells with JAK2 and STAT3 inhibitors, it was found that only tf and fpn1 were regulated by maIL-6 trans-signaling through the JAK2/STAT3 pathway. These findings provided novel insights into IL-6 trans-signaling regulatory mechanism in teleost, enriching our knowledge of fish immunity and iron metabolism.

Keywords: IL-6; Immunoregulation; Iron metabolism; JAK2/STAT3; Megalobrama amblycephala; Trans-signaling; Transcriptome.

Publication types

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

MeSH terms

Animals
Cypriniformes*
Inflammation
Interleukin-6* / metabolism
Iron
Mammals
Signal Transduction

Substances

Interleukin-6
Iron