RESUMEN
The angiopoietin-like 4 (ANGPLT4) protein is involved in lipid metabolism and is known to inhibit lipoprotein lipase in the bloodstream. We investigated the effect of milk on intestinal ANGPTL4 and the metabolic profile of growing pigs and the effect of free fatty acids (FFAs) on ANGPTL4 in ex vivo and in vitro assays. Feeding pigs whole milk increased intestinal ANGPTL4 mRNA and increased fecal excretion of long-chain FFA compared to the control group fed soybean oil (n = 9). Furthermore, FFAs (C4-C8) induced ANGPTL4 gene expression in porcine intestinal tissue mounted in Ussing chambers and ANGPTL4 protein secretion to both the apical and basolateral sides of intestinal Caco-2 cells on permeable membranes. Altogether, these results support an ANGPTL4-induced secretion of fecal FFAs. Urinary levels of FFAs (C4-C12), 3-hydroxyadipic acid, and suberic acid were also increased by milk consumption, indicating higher energy expenditure compared to the control group.
Asunto(s)
Angiopoyetinas/metabolismo , Ácidos Grasos/farmacocinética , Heces/química , Mucosa Intestinal/metabolismo , Leche , Proteína 4 Similar a la Angiopoyetina , Angiopoyetinas/genética , Animales , Células CACO-2 , Dieta , Ácidos Grasos/metabolismo , Ácidos Grasos/orina , Femenino , Regulación de la Expresión Génica , Humanos , Aceite de Soja/farmacología , Sus scrofaRESUMEN
Supplementation of benzoic acid to pig diets reduces the pH of urine and may thereby affect emissions of ammonia and other gases from slurry, including sulfur-containing compounds that are expected to play a role in odor emission. Over a period of 112 d, we investigated hydrogen sulfide (H(2)S), methanethiol (MT), dimethyl sulfide (DMS), dimethyl disulfide (DMDS), and dimethyl trisulfide (DMTS), as well as ammonia and methane emissions from stored pig slurry. The slurry was derived from a feeding experiment with four pig diets in a factorial design with 2% (w/w) benzoic acid and 1% (w/w) methionine supplementation as treatments. Benzoic acid reduced slurry pH by 1 to 1.5 units and ammonia emissions by 60 to 70% for up to 2 mo of storage, and a considerable, but transitory reduction of methane emissions was also observed after 4 to 5 wk. All five volatile sulfur (S) compounds were identified in gas emitted from the slurry of the control treatment, which came from pigs fed according to Danish recommendations for amino acids and minerals. The emission patterns of volatile S compounds suggested an intense cycling between pools of organic S in the slurries, with urinary sulfate as the main source. Diet supplementation with methionine significantly increased all S emissions. Diet supplementation with benzoic acid reduced emissions of H(2)S and DMTS compared with the control slurry and moderately increased the concentrations of MT. Sulfur gas emissions were influenced by a strong interaction between methionine and benzoic acid treatments, which caused a significant increase in emissions of especially MT, but also of DMDS. In conclusion, addition of 2% benzoic acid to pig diets effectively reduced ammonia volatilization, but interactions with dietary S may increase odor problems.