Transport of Neutral Amino Acids in the Jejunum of Pigs with Special Consideration of L-Methionine

• Published in: Nutrients 2024-10, Vol.16 (19), p.3418
• Main Authors: Schermuly, Isabel I, Romanet, Stella, Patra, Amlan K, Mastrototaro, Lucia, Lemme, Andreas, Pieper, Robert, Zentek, Jürgen, Aschenbach, Jörg R
• Format: Article
• Language: English
• Subjects: Amino acid metabolism; Amino Acids, Neutral - metabolism; Animal Feed - analysis; Animals; Biological Transport; Diet; Dietary Supplements; Food and nutrition; Health aspects; Hogs; Inflammation; Intestinal Mucosa - metabolism; Jejunum; Jejunum - drug effects; Jejunum - metabolism; Male; Methionine; Methionine - metabolism; Nutrition research; Physiological aspects; Small intestine; Swine
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu16193418

Methionine (Met) is a popular nutritional supplement in humans and animals. It is routinely supplemented to pigs as L-Met, DL-Met, or DL-2-hydroxy-4-(methylthio) butanoic acid (DL-HMTBA). We investigated the effect of these Met supplements on jejunal amino acid (AA) transport in male castrated Piétrain × Danbred pigs, also including a non-supplemented group. The mucosal-to-serosal flux of ten [ C]-labeled AAs (L-glutamine, glycine, L-leucine, L-lysine, L-Met, L-serine, L-threonine, L-tryptophan, L-tyrosine and L-valine) was investigated at two concentrations (50 µM and 5 mM). Inhibition of apical uptake by mucosal L-Met was also measured for these AAs. The intestinal expression of apical AA transporters, angiotensin-converting enzyme II and inflammation-related genes were compared with those of a previous study. Except for tryptophan and lysine at 5 mM, all AA fluxes were Na -dependent ( ≤ 0.05), and the uptake of most AAs, except glycine and lysine, was inhibited by L-Met ( < 0.001). A correlation network existed between Na -dependent fluxes of most AAs (except tryptophan and partly glycine). We observed the upregulation of B AT1 ( ) ( < 0.001), the downregulation of ATB ( ) ( < 0.001) and a lower expression of , , , and in the present vs. the previous study ( < 0.001). The correlating AAs likely share the same Na -dependent transporter(s). A varying effect of the Met supplement type on AA transport in the two studies might be related to a different level of supplementation or a different inflammatory status of the small intestine.