Exogenous sulphide donors modify the gene expression patterns of Atlantic salmon nasal leukocytes

Embracing prospects for reducing the numbers of animals used in aquaculture research

“…Finally, another in vitro approach that should not be overlooked is using the same fish for different cell isolation purposes. (Alipio et al, 2022;Cabillon & Lazado, 2022;Lazado, Voldvik, et al, 2023).…”

“…However, we would like to point out that these in vitro model systems are targeted replacements to fish trials and can be utilized as a way of refining future large‐scale trials (Rehberger et al, 2018). These in vitro models are excellent systems for understanding the underlying biological mechanisms of a specific stimulus, which can be challenging in an in vivo trial where several factors are interacting, thus posing compound effects that are difficult to isolate (Cabillon & Lazado, 2022; Torrissen et al, 2023). In vivo exposure trials involving aquaculture‐relevant stimuli often require a significant number of fish and are costly.…”

Sulphide donors affect the expression of mucin and sulphide detoxification genes in the mucosal organs of Atlantic salmon (Salmo salar)

“…In Atlantic salmon, a recent study reported the first ever transcriptome-wide response of nasal leukocytes to two forms of sulphide donors: the salt sodium hydrosulfide (NaHS) and the organic analogue morpholin-4-ium 4-methoxyphenyl (morpholino) phosphinodithioate (GYY4137) ( Cabillon and Lazado, 2022 ). NaHS is a fast-release sulphide donor that instantly transforms to H 2 S upon exposure to aqueous solution.…”

“…GYY4137 is a slow-releasing sulphide donor, which takes at least an hour to be transformed into H 2 S ( Li et al, 2008 ). The previous study found that exposure to these exogenous H 2 S donors is less likely to affect the cell viability of Atlantic salmon nasal leukocytes but can influence oxidative stress, innate and adaptive immunity, and interleukin signalling—particularly at higher concentrations ( Cabillon and Lazado, 2022 ). Although abundant research has been done to elucidate the mechanisms of H 2 S in mammals and other vertebrate animals, studies in fish mucosa-H 2 S interactions are quite limited.…”

“…This study explored the molecular responses of Atlantic salmon mucosa to H 2 S. We utilised mucosal organ explants from the gills and olfactory organ of Atlantic salmon to study the mucosal consequences of H 2 S. These two mucosal organs were selected as models based on previous studies in salmon showing their responsiveness to H 2 S ( Kiemer et al, 1995 ; Cabillon and Lazado, 2022 ). We focused on how H 2 S, in the form of a sulphide donor NaHS, affected the transcription of important genes encoding sulphide detoxification and mucins.…”