International Journal of Molecular Sciences · 5 authors, 2 centres
This summary was generated by AI from a single paper. It has not been reviewed by a clinician and is not clinical advice. Verify against the source before acting on it.
This study characterized fatty acid sensing mechanisms in the gastrointestinal tract of rainbow trout by intragastrically administering fatty acids and measuring mRNA and protein levels. It found that trout have similar but divergent mechanisms compared to mammals, with limitations in not testing functional outcomes or human applicability.
The gastrointestinal tract senses nutrients to regulate feeding, but mechanisms in fish are poorly known. This study characterizes fatty acid sensing in rainbow trout GIT. Methods: Rainbow trout (n=6 per treatment) were fasted for 48 hours and intragastrically administered fatty acids (octanoate, oleate, ALA, butyrate) or vehicle. GIT samples were collected at 20 min and 2 h post-administration. mRNA and protein levels of fatty acid receptors, transporters, intracellular signaling molecules, and hormones were measured using RT-qPCR and Western blot. Key Results: Trout GIT expresses mRNAs for fatty acid receptors (Ffar isoforms, Gpr84, Gpr119) and transporters (CD36, FATP4, MCT-1). Different fatty acids modulated expression of these genes and hormones like ghrelin, CCK, PYY, GLP-1. For example, oleate and ALA upregulated Ffar1 and Ffar2b1.2, while butyrate affected Gpr84 and MCT-1. Hormonal responses varied, with octanoate and oleate increasing anorexigenic hormones, and butyrate increasing orexigenic ghrelin. Limitations: The study is based on mRNA and protein levels, not functional outcomes like hormone release or feed intake; it is in fish, so direct human relevance is indirect. Implications: This provides the first evidence of fatty acid sensing mechanisms in fish GIT, showing similarities and differences from mammals, which may inform aquaculture nutrition and evolutionary biology.
