Expression of genes coding for selected amino acid transporters in small intestine, liver, and skeletal muscle of pigs fed excess branched-chain amino acids.
Excess Leu reduces the availability of Ile and Val in pigs likely by reducing absorption of the latter amino acids (AA). Twenty-four crossbred pigs were used to evaluate the effect of excess Leu alone or with surplus Ile and Val on the expression of cationic (b(0),(+)AT and CAT1) and neutral (B(0)AT1) AA transporters in the small intestine, liver, and skeletal muscle. Dietary treatments included: 1) basal diet; 2) basal plus 0.43% L-Leu (excess Leu); 3) basal plus 0.43% Leu, 0.20% L-Ile, and 0.25% L-Val (excess Leu, Ile, and Val). The basal diet contained 0.90% standardized ileal digestible Lys, as well as crystalline L-Lys, L-Thr, DL-Met, L-Trp, L-Leu, L-Ile, L-His, and L-Val. Diets 2 and 3 contained 52% more Leu and diet 3 contained 42% more Ile and Val compared with the basal diet. Excess Leu or excess Leu, Ile, and Val reduced b(0),(+)AT expression in the jejunum (P < 0.05) but had no effect in the ileum and liver. Excess Leu increased CAT1 expression in the ileum but reduced expression in the liver (P < 0.05). Excess Leu, Ile, and Val increased (P < 0.05) B(0)AT1 expression in the jejunum and tended to increase (P = 0.10) expression in the ileum. In general, b(0),(+)AT expression was higher but CAT1 expression was lower in the jejunum than in the ileum; B0AT1 was similarly expressed in the jejunum and ileum. Excess Leu or any branched-chain AA affects AA transporter expression, which may affect the absorption and availability of AA for animal growth.
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, México.
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Cervantes
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, México.
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Arce
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, México.
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García
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, México.
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Cota
Shaanxi Institute of Zoology, Northwest Institute of Endangered Zoological Species, Xi'an, China.
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Htoo
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali, México adriana_morales@uabc.edu.mx.
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Morales
D026905:Amino Acid Transport Systems / Q000235:genetics*; D000597:Amino Acids, Branched-Chain / Q000008:administration & dosage; D000821:Animal Feed; D000818:Animals; D015870:Gene Expression; D007082:Ileum / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism*; D007583:Jejunum / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D013552:Swine
D026905:Amino Acid Transport Systems; D000597:Amino Acids, Branched-Chain