State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, China; Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China; Key Laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China.
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, China; Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China; Key Laboratory of Applied Marine Biotechnology of Ministry of Education, Ningbo University, Ningbo 315211, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), China.
Gen Comp Endocrinol. 2022 Jan 1;315:113796. doi: 10.1016/j.ygcen.2021.113796. Epub 2021 Apr 24.
Adrenocorticotropic hormone (ACTH), a bioactive peptide of the family of melanocortins, is generated from pro-opiomelanocortin (POMC). So far, the research on the specific functions of ACTH in the immune system of teleosts is limited. We determined two complementary DNA (cDNA) sequences of POMC in ayu (Plecoglossus altivelis), termed PaPOMC-A and PaPOMC-B. PaPOMCs transcripts occurred in all examined tissues, and their expression in immune tissues changed following experimental infection with Vibrio anguillarum. PaACTH-B, but not PaACTH-A, suppressed the phagocytosis of monocytes/macrophages (MO/MФ). Two isoforms of PaACTH increased the bactericidal capacity of MO/MФ. PaACTH-A increased anti-inflammatory cytokine expression, while PaACTH-B decreased pro-inflammatory cytokine expression in MO/MФ. Compared with PaACTH-B treatment, the PaACTH-A treatment improved survival rate and reduced the bacterial load in V. anguillarum-infected ayu through interleukin (IL)-10. Our results indicate that the two PaACTH isoforms exert different effects in the host defense against bacterial infection.
促肾上腺皮质激素（ACTH）是一种生物活性肽家族的黑素细胞刺激素，由前阿黑皮素原（POMC）生成。到目前为止，关于 ACTH 在硬骨鱼类免疫系统中的特定功能的研究还很有限。我们在牙鲆（Plecoglossus altivelis）中确定了两种 POMC 的 cDNA 序列，分别命名为 PaPOMC-A 和 PaPOMC-B。PaPOMCs 转录本存在于所有检测到的组织中，其在免疫组织中的表达在实验感染鳗弧菌后发生变化。PaACTH-B，但不是 PaACTH-A，抑制了单核细胞/巨噬细胞（MO/MФ）的吞噬作用。两种 PaACTH 同工型增加了 MO/MФ 的杀菌能力。PaACTH-A 增加了抗炎细胞因子的表达，而 PaACTH-B 降低了 MO/MФ 中促炎细胞因子的表达。与 PaACTH-B 处理相比，PaACTH-A 处理通过白细胞介素（IL）-10 提高了牙鲆的存活率并降低了鳗弧菌感染牙鲆中的细菌负荷。我们的结果表明，两种 PaACTH 同工型在宿主抵抗细菌感染的防御中发挥不同的作用。
