α-MSH is partially involved in the immunomodulation of Nile tilapia (Oreochromis niloticus) antibacterial immunity

Qi Li; Baijian Jiang; Zhiqiang Zhang; Yongxiong Huang; Zhou Xu; Xinjin Chen; Yu Huang; Jichang Jian; Qingpi Yan

doi:10.1016/j.fsi.2022.11.001

α-MSH is partially involved in the immunomodulation of Nile tilapia (Oreochromis niloticus) antibacterial immunity

Fish Shellfish Immunol. 2022 Dec:131:929-938. doi: 10.1016/j.fsi.2022.11.001. Epub 2022 Nov 4.

Authors

Qi Li¹, Baijian Jiang², Zhiqiang Zhang², Yongxiong Huang², Zhou Xu², Xinjin Chen², Yu Huang³, Jichang Jian⁴, Qingpi Yan⁵

Affiliations

¹ Fisheries College, Jimei University, Xiamen, China; College of Fishery, Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Zhanjiang, China.
² College of Fishery, Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Zhanjiang, China.
³ College of Fishery, Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Zhanjiang, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen, China.
⁴ College of Fishery, Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Zhanjiang, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen, China. Electronic address: jianjc@gdou.edu.cn.
⁵ Fisheries College, Jimei University, Xiamen, China. Electronic address: yanqp@jmu.edu.cn.

PMID: 36343851
DOI: 10.1016/j.fsi.2022.11.001

Abstract

α-Melanocyte-stimulating hormone (α-MSH) is a well-studied neuropeptide controlling skin and hair color. Besides, numerous immunomodulation roles of α-MSH were recorded in humans and mice. However, the regulatory effects of α-MSH in teleost immunity haven't been well elucidated. In this study, several precursor molecules of α-MSH (POMCs) and its receptors (MCRs) in Nile tilapia (Oreochromis niloticus) were characterized, and their expression characteristics and specific functions on antibacterial immunity were determined. Overall, POMCs and MCRs were principally detected in the brain, skin, and liver, and were remarkably promoted post Streptococcus agalactiae infection. However, tiny POMCs and MCRs were observed in tilapia immune organs (head kidney and spleen) or lymphocytes, and no evident immunomodulation effect was detected in vitro. Moreover, the in vivo challenge experiments revealed that α-MSH protects tilapia from bacterial infection by regulating responses in the brain and intestine. This study lays theoretical data for a deeper comprehension of the immunomodulation mechanisms of teleost α-MSH and the evolutional process of the vertebrate melanocortin system.

Keywords: MCR; Nile tilapia; POMC; Streptococcus agalactiae; α-MSH.

MeSH terms

Amino Acid Sequence
Animals
Anti-Bacterial Agents
Cichlids / immunology
Cichlids / microbiology
Fish Diseases* / immunology
Fish Diseases* / microbiology
Fish Proteins / chemistry
Gene Expression Regulation
Immunomodulation* / physiology
Streptococcal Infections* / veterinary
Streptococcus agalactiae / physiology
Tilapia* / immunology
Tilapia* / microbiology
alpha-MSH* / metabolism

Substances

alpha-MSH
Anti-Bacterial Agents
Fish Proteins