Transcriptional Signatures of Immune, Neural, and Endocrine Functions in the Brain and Kidney of Rainbow Trout (Oncorhynchus mykiss) in Response to Aeromonas salmonicida Infection

Abstract

Rainbow trout (Oncorhynchus mykiss) serves as one of the most important commercial fish with an annual production of around 800,000 tonnes. However, infectious diseases, such as furunculosis caused by Aeromonas salmonicida infection, results in great economic loss in trout culture. The brain and kidney are two important organs associated with “sickness behaviors” and immunomodulation in response to disease. Therefore, we worked with 60 trout and investigated transcriptional responses and enrichment pathways between healthy and infected trout. We observed that furunculosis resulted in the activation of toll-like receptors with neuroinflammation and neural dysfunction in the brain, which might cause the “sickness behaviors” of infected trout including anorexia and lethargy. We also showed the salmonid-specific whole genome duplication contributed to duplicated colony stimulating factor 1 (csf-1) paralogs, which play an important role in modulating brain immunomodulation. Enrichment analyses of kidneys showed up-regulated immunomodulation and down-regulated neural functions, suggesting an immune-neural interaction between the brain and kidney. Moreover, the kidney endocrine network was activated in response to A. salmonicida infection, further convincing the communications between endocrine and immune systems in regulating internal homeostasis. Our study provided a foundation for pathophysiological responses of the brain and kidney in response to furunculosis and potentially offered a reference for generating disease-resistant trout strains.

Pleiotropic Role of Rainbow Trout CXCRs in Response to Disease and Environment: Insights from Transcriptional Signatures and Structure Analysis

“…Brain, kidney, and spleen samples were collected from control, asymptomatic, and symptomatic rainbow trout after V. anguillarum challenge, and 27 libraries of RNA-Seq samples were used (3 phenotypes × 3 tissues × 3 replicates [ 40 , 42 ]). Brain and kidney samples from rainbow trout were challenged with Aeromonas salmonicida ([ 43 ]). Brain and kidney samples were collected from control and infected rainbow trout, and the RNA-Seq dataset included 12 libraries (2 (control vs. infection) × 2 tissues × 3 replicates [ 43 ]).…”

“… Brain and kidney samples from rainbow trout were challenged with Aeromonas salmonicida ([ 43 ]). Brain and kidney samples were collected from control and infected rainbow trout, and the RNA-Seq dataset included 12 libraries (2 (control vs. infection) × 2 tissues × 3 replicates [ 43 ]). Brain, kidney, and liver samples from rainbow trout with environmental salinity changes ([ 44 ]).…”

Crosstalk between Growth and Osmoregulation of GHRH-SST-GH-IGF Axis in Triploid Rainbow Trout (Oncorhynchus mykiss)

“…The correlation analysis of gene expressions was analyzed via the Pearson correlation coefficient by MetaboAnalyst and GraphPad Prism 8.0. Data of basal expression of ghrh-gh-sst-igf axis in diploid trout were retrieved from previously published RNA-Seq data (SRA of NCBI: PRJNA865462 for liver; SRA of NCBI: PRJNA753277 for brain and kidney) [ 69 , 70 ]. The gene count data were analyzed by DESeq2 R package and then the average count was normalized by average β-actin ((average of normalized count × 10,000)/(average of β-actin count)) [ 60 ].…”

Probiotics Mediate Intestinal Microbiome and Microbiota-Derived Metabolites Regulating the Growth and Immunity of Rainbow Trout (Oncorhynchus mykiss)

“…This poses a major challenge for sustainable aquaculture of rainbow trout. Aeromonas salmonicida , in particular, is one of the most infective and lethal pathogens, causing serious furunculosis and huge economic losses ( 4 ). In addition, antibiotics, as the classic cure for microbial infection in the aquaculture industry, have been widely restricted due to the emergence of drug resistance genes ( 5 , 6 ).…”