European Sea Bass (Dicentrarchus labrax) Immune Status and Disease Resistance Are Impaired by Arginine Dietary Supplementation

Abstract

Infectious diseases and fish feeds management are probably the major expenses in the aquaculture business. Hence, it is a priority to define sustainable strategies which simultaneously avoid therapeutic procedures and reinforce fish immunity. Currently, one preferred approach is the use of immunostimulants which can be supplemented to the fish diets. Arginine is a versatile amino acid with important mechanisms closely related to the immune response. Aiming at finding out how arginine affects the innate immune status or improve disease resistance of European seabass (Dicentrarchus labrax) against vibriosis, fish were fed two arginine-supplemented diets (1% and 2% arginine supplementation). A third diet meeting arginine requirement level for seabass served as control diet. Following 15 or 29 days of feeding, fish were sampled for blood, spleen and gut to assess cell-mediated immune parameters and immune-related gene expression. At the same time, fish from each dietary group were challenged against Vibrio anguillarum and survival was monitored. Cell-mediated immune parameters such as the extracellular superoxide and nitric oxide decreased in fish fed arginine-supplemented diets. Interleukins and immune-cell marker transcripts were down-regulated by the highest supplementation level. Disease resistance data were in accordance with a generally depressed immune status, with increased susceptibility to vibriosis in fish fed arginine supplemented diets. Altogether, these results suggest a general inhibitory effect of arginine on the immune defences and disease resistance of European seabass. Still, further research will certainly clarify arginine immunomodulation pathways thereby allowing the validation of its potential as a prophylactic strategy.

Dietary arginine supplementation mitigates the soybean meal induced enteropathy in juvenile turbot,Scophthalmus maximusL.

“…In addition, no more benefit was showed in ARG2, and the study by Azeredo et al. () even showed that European seabass ( Dicentrarchus labrax ) immune status and disease resistance could be impaired by excess dietary arginine; therefore, the suitable dosage for arginine supplementation merits closer attention to determine.…”

“…In the present study, after 12-week feeding, the typical symptoms of SBMIE described by Gu, Bai, Zhang and Krogdahl (2016) as an essential amino acid was met in all groups (Fournier et al, 2003). In addition, no more benefit was showed in ARG2, and the study by Azeredo et al (2015) even showed that European seabass (Dicentrarchus labrax) immune status and disease resistance could be impaired by excess dietary arginine; therefore, the suitable dosage for arginine supplementation merits closer attention to determine.…”

Beyond muscles: The untapped potential of creatine

“…There have also been a small number of studies that suggest that pro-inflammatory responses are reduced following creatine supplementation [17–24]. However, the mechanism of how creatine acts in modulating inflammation remains unclear, although recent work [25] demonstrating that European sea bass fed a diet supplemented with arginine (a precursor of creatine) had reduced disease resistance suggests that the mechanism may be evolutionarily conserved. The potential of creatine as an immunomodulator may have important implications for individuals with certain pro-inflammatory diseases such as arthritis.…”

Effects of the Dietary Tryptophan and Aspartate on the Immune Response of Meagre (Argyrosomus regius) after Stress

“…The effects of amino acids on fish immune system have been studied in some fish species of interest in aquaculture practices such as European sea bass and salmonids. For example, it has been demonstrated that European sea bass immune status and disease resistance were impaired when fed Arg-supplemented diets (1% and 2%) [24]. Furthermore, methionine has higher effect on the innate immune response to inflammation than Trp [25], while Trp and its metabolites stimulated T-regulatory cells [26].…”