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Transforming growth factor-β activated kinase-1 (TAK1) is an important upstream signaling molecules involved in the NF-κB signaling pathway. TAK1 interacts with TAB1 to form the TAK1–TAB1 complex, which elicits NF-κB activation through a series of cascade reactions in mammals. However, the function of TAK1 in blunt snout bream (Megalobrama amblycephala (maTak1) and the effects of their interaction between TAK1 and TAB1 on the NF-κB activation still remains largely unknown. In the present study, maTak1 was cloned and characterized successfully based on transcriptome data. Its open reading frame is composed of 1626 nucleotides and the predicted maTAK1 protein contains 541 amino acids, which includes an N-terminal Serine/Threonine protein kinases (S/TKc) and a C-terminal coiled-coil region. Phylogenetic analysis showed that maTAK1 were clustered with those of other teleosts. MaTak1 displayed ubiquitous transcriptional expression in all the examined tissues of healthy blunt snout bream but with varied expression levels. And maTrak1 expression was dramatically enhanced in different tissues and MAF cells after LPS stimulation and A. hydrophila challenge. The result from subcellular localization analysis indicated that both maTAK1 and maTAB1 were cytoplasmic protein. The activity of NF-κB promoter could not be induced by overexpression of maTak1 or maTab1 alone, however, it could be enhanced by co-expression of maTak1 and maTab1. Co-immunoprecipitation and subcellular co-localization assay revealed that maTAK1 can combine with maTAB1 directly. The transcriptional expression level of pro-inflammatory cytokines (IL-1β, IL-6 and IL-8) increased distinctly after the overexpression of maTak1 and maTab1. Taken together, the data obtained in this study demonstrated that the direct interaction between maTAK1 and maTAB1 might play a pivotal role in mediating host innate immune response to pathogen invasion by the production of pro-inflammatory cytokines via NF-κB signaling pathway, which might lay a solid foundation for the establishment of novel therapeutic approach to combat bacterial infection in fish. • MaTrak1 was constitutively expressed in all tissues examined. • MaTrak1 expression was dramatically enhanced in different tissues and MAF cells after immune stimulation. • Both maTAK1 and maTAB1 protein localized in cytoplasm. • MaTAK1 could directly interact with maTAB1 in vitro. • MaTAK1-maTAB1 interaction increases pro-inflammatory cytokine production via promotion of NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

As an environmental enrichment, music can positively influence the immune function, while noise has an adverse effect on the physical and mental health of humans and animals. However, whether music-enriched environments mitigate noise-induced acute stress remains unclear. To investigate the anti-inflammatory effects of music on the immune organs of broiler chickens under conditions of early-life acute noise stress, 140 one-day-old white feather broilers (AA) were randomly divided into four groups: control (C), the music stimulation (M) group, the acute noise stimulation (N) group, the acute noise stimulation followed by music (NM) group. At 14 days of age, the N and NM groups received 120 dB noise stimulation for 10 min for one week. After acute noise stimulation, the NM group and M group were subjected to continuous music stimulation for 14 days (6 h per day, 60 dB). At 28 days of age, the body temperature of the chicks, the histopathological changes, quantification of ROS-positive density and apoptosis positivity in tissues of spleen, thymus, and bursa of Fabricius (BF) were measured. The results showed that acute noise stimulation led to an increase in the number and area of splenic microsomes and the cortex/medulla ratio of the detected immune organs. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of immune tissues of broilers in N group were decreased compared to the broilers in C group, while the mRNA levels of malondialdehyde (MDA), TNF-α, IL-1, and IL-1β increased. In addition, the gene and protein expression levels of IKK, NF-κB, and IFN-γ of three immune organs from broilers in the N group were increased. Compared to the C and N group, chickens from the NM group showed a decrease in the number and area of splenic follicles, an increase in the activities of SOD and GSH-Px, and a decrease in the expression levels of MDA, TNF-α, IL-1, and IL-1β. Therefore, a music-enriched environment can attenuate oxidative stress induced by acute noise stimulation, inhibiting the activation of the NF-κB signaling pathway and consequently alleviating the inflammatory response in immune organs. [Display omitted] • We have discovered that acute noise stimulation induces oxidative stress and inflammation in immune organs. • Music is an affordable complementary therapy that can help mitigate the immune system damage caused by acute noise exposure. • Thermal imaging showed that noise induces inflammation in chicks further causing an increase in body temperature. [ABSTRACT FROM AUTHOR]

Interleukin-1 receptor-associated kinase 4 (IRAK4) plays a crucial role in the Toll-like receptor/IL-1R signal pathway, which mediates the downstream signal transduction involved in innate and adaptive immunity. In the present study, an IRAK4 homologue (named as MaIRAK4) from blunt snout bream (Megalobrama amblycephala) was cloned and characterized. The open reading frame (ORF) of MaIRAK4 contains 1422 nucleotides, encoding a putative protein of 473 amino acids. Protein structural analysis revealed that MaIRAK4 has an N-terminal death domain (DD) and a central kinase domain (S_TKc), similar to those of mammals and other fishes. Multiple sequence alignment demonstrated that MaIRAK4 is highly homologous with that of grass carp (97.67%). The qRT-PCR analysis showed that MaIRAK4 expressed widely in all examined tissues, including heart, liver, spleen, kidney, head-kidney, gill, intestine and muscle, with the highest expression in the liver and spleen. After stimulation with LPS, MaIRAK4 expression upregulated significantly and reached a peak at 6 h and 12 h post LPS stimulation in the spleen and head-kidney, respectively. After challenge with Aeromonas hydrophila , MaIRAK4 expression peaked at 48 h and 72 h in spleen/head-kidney and liver, respectively. These results implied that MaIRAK4 is involved in the host defense against bacterial infection. Subcellular localization analysis indicated that MaIRAK4 distributed in the cytoplasm. Co-immunoprecipitation and subcellular co-localization assay revealed that MaIRAK4 can combine with MaMyD88 through DD domain. MaIRAK4 overexpression can induce slightly the NF-κB promoter activity in HEK 293 cells. However, the activity of NF-κB promoter was dramatically enhanced after co-transfection with MaIRAK4 and MaMyD88 plasmids. The results showed that MaIRAK4 was involved in NF-κB signal pathway mediated by maMyD88. The expression level of pro-inflammatory cytokines (IL-1β, IL-6, IL-8 and TNF-α) decreased significantly after the siRNA-mediated knockdown of MaIRAK4. Together, these results suggest that MaIRAK4 plays an important function in the innate immunity of M. amblycephala by inducing cytokines expression. • An IRAK4 orthologue from blunt snout bream was identified and characterized. • MaIRAK4 expression was markedly enhanced after immune stimulations. • MaIRAK4 distributed in cytoplasm and co-localized with MaMyD88. • MaIRAK4 could directly interact with MaMyD88 through DD domain. • MaIRAK4 promotes pro-inflammatory cytokines production via MaMyD88 -mediated NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Toll-interacting protein (Tollip) is an important negative regulator of Toll-like receptor-mediated innate immunity by preventing excessive proinflammatory responses. The structure and function of Tollip have been well identified in mammals, but the piscine Tollip remains poorly understood. In the present study, a homologue of Tollip was identified and characterized from blunt snout bream (named MaTollip), which was composed of an 831 bp open reading frame encoding a protein of 276 amino acids. Phylogenetic analysis indicated that MaTollip is a novel member of Tollip family and possessed the highest similarity to that of grass carp (99.28%). Multiple alignment of amino acid sequence showed that MaTOLLIP shared a high degree of structural conservation, including a TBD domain, a C2 domain and a CUE domain, with its counterparts from other vertebrates. With regard to tissue-specific expression without immune challenge, MaTollip was constitutively expressed in a wide range of normal tissues, with the highest in the head-kidney and the lowest in the intestine. MaTollip expression in the head-kidney was strongly upregulated upon LPS stimulation and A. hydrophila infection. Fluorescence microscopic analysis revealed that the green fluorescent protein-TOLLIP was localized predominantly in the cytoplasm of EPC cells in a dot-like state. When MaTollip was overexpressed in HEK-293T and EPC cells, it could significantly inhibit the activity of nuclear factor-κB (NF-κB) promoter in a dose dependent manner. MaTollip overexpression in MAF cells lowered drastically the transcriptional expression level of lipopolysaccharide-induced proinflammatory cytokines (IL-1β , IL-6 and IL-8), whereas they were dramatically promoted by MaTollip knock down with siRNA. Taken together, this study demonstrated that MaTollip played a pivotal role in mediating host innate immune response to pathogen invasion, and unveiled the involvement of MaTollip in NF-κB-mediated transcription of inflammation genes, which paved the way for further studies of immune negative regulation mechanisms mediated by Tollip in fish. • An MaTollip orthologue from blunt snout bream was identified and characterized. • MaTollip mRNA transcripts were constitutively expressed in all examined tissues. • MaTollip expression was significantly elevated after immune stimulations. • MaTollip located in cytoplasm in a dot-like state. • MaTollip decreased the pro-inflammatory cytokines production through inhibition of NF-ĸB signal pathway. [ABSTRACT FROM AUTHOR]