Iron Overload Is Associated With Oxidative Stress and Nutritional Immunity During Viral Infection in Fish

Abstract

Iron is a trace element, essential to support life due to its inherent ability to exchange electrons with a variety of molecules. The use of iron as a cofactor in basic metabolic pathways is essential to both pathogenic microorganisms and their hosts. During evolution, the shared requirement of micro- and macro-organisms for this important nutrient has shaped the pathogen–host relationship. Infectious pancreatic necrosis virus (IPNv) affects salmonids constituting a sanitary problem for this industry as it has an important impact on post-smolt survival. While immune modulation induced by IPNv infection has been widely characterized on Salmo salar, viral impact on iron host metabolism has not yet been elucidated. In the present work, we evaluate short-term effect of IPNv on several infected tissues from Salmo salar. We observed that IPNv displayed high tropism to headkidney, which directly correlates with a rise in oxidative stress and antiviral responses. Transcriptional profiling on headkidney showed a massive modulation of gene expression, from which biological pathways involved with iron metabolism were remarkable. Our findings suggest that IPNv infection increase oxidative stress on headkidney as a consequence of iron overload induced by a massive upregulation of genes involved in iron metabolism.

Commissioning of the BRIKEN detector for the measurement of very exotic β-delayed neutron emitters

“…A similar simulation was made using the known spectrum of 252 Cf [20] extending up to 20 MeV with an average energy of E n = 2.13 MeV and a value of 61.8% was obtained . This value agrees well with the experimental result of 61.4(17)% obtained during the characterization of the BRIKEN neutron counter with a 252 Cf source [21]. From these results we set the nominal neutron detection efficiency of the counter in the present configuration for isotopes with low or moderate Q β1n windows toε n = 66.8 (20)%.…”

Antimicrobial Peptides of Salmonid Fish: From Form to Function

“…Other viruses that infect salmonids include infectious pancreatic necrosis virus (IPNV); this virus is unique because it leads to substantial changes in iron metabolism within the head kidney via the upregulation of genes involved in iron metabolism, including hepcidin, and subsequently leading to oxidative stress [ 67 ]. Unlike IHNV, IPNV infection in Atlantic salmon does not increase hepc in the head kidney, but does upregulate hepc gene expression in liver and red blood cells.…”

“…Unlike IHNV, IPNV infection in Atlantic salmon does not increase hepc in the head kidney, but does upregulate hepc gene expression in liver and red blood cells. In addition to this, IPNV leads to an upregulation of cath mRNA in the head kidney and red blood cells of infected fish [ 67 ]. Interestingly, IPNV infection significantly increases the plasma levels of both Cath and Hepc [ 67 ], suggesting that AMPs may be involved in systemic responses to IPNV infection.…”

Pharmacological iron-chelation as an assisted nutritional immunity strategy against Piscirickettsia salmonis infection

“…The results indicate that although the challenged fish treated with DFO mesylate salt did not show an improvement in survival with respect to the control, the bacterial load was significantly reduced in these fish, highlighting the critical role of iron for P. salmonis replication during the infection. Although our results demonstrate that DFP was able to control the replication of P. salmonis at non-antibiotic concentrations (Figures 2 , 3 ), we cannot discard that DFP directly exerts an inhibitory activity on the bacterial virulence, or indirectly stimulates the immune response and/or the antioxidant capacity of the fish by systemic reduction of iron excess [ 59 , 60 ]. Finally, given the increasing prevalence of antibiotic resistance, our results collectively offer the possibility to combat SRS and other fish infections in an efficient and sustainable form by using dietary DFP as a monotherapy or as an adjuvant therapy with lower doses than currently used antibiotics.…”