Short-Term Oral UMP/UR Administration Regulates Lipid Metabolism in Early-Weaned Piglets

Abstract

Simple SummaryUridine monophosphate (UMP) and uridine (UR) are rich in sow’s milk. The results from this study showed that UMP and UR affect the lipid profile and lipid metabolism in weanling piglets. It is suggested that UMP and UR improve the energy status in early-weaned piglets.AbstractAs a main ingredient of milk, the nucleotides content is about 12–58 mg/g, which plays a critical role in maintaining cellular function and lipid metabolism. This study was conducted to evaluate the effects of short-term uridine monophosphate (UMP) and uridine (UR) administration on lipid metabolism in early-weaned piglets. Twenty-one weaned piglets (7 d of age; 3.32 ± 0.20 kg average body weight) were randomly assigned into three groups: The control (CON), UMP, and UR group, and oral administered UMP or UR for 10 days, respectively. The results showed that supplementation with UMP significantly increased (p < 0.05) serum low density lipoprotein (LDL) and tended to increase (p = 0.062) serum total cholesterol (TC) content of piglets when compared with the other two groups. Oral administration with UMP and UR significantly decreased (p < 0.05) the serum total bile acid (TBA) and plasma free fatty acids (FFA) of piglets, and significantly reduced the fatty acid content of C12:0 (p < 0.01) and C14:0 (p < 0.05) in liver. Experiments about key enzymes that are involved in de novo synthesis of fatty acid showed that the gene expression of liver X receptors (LXRα), sterol regulatory element-binding transcription factor 1 (SREBP1c), fatty acid desaturase 2 (FADS2), and fatty acid elongase 5 (ELOVL5) were remarkably down-regulated (p < 0.05) with UMP and UR treatment, and key factors of adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), and carnitine palmitoyl transferase 1 (CPT-1α) involved in fatty acid catabolism were also decreased (p < 0.05). Additionally, the protein expression of phosphorylated-mTOR was not affected while phosphorylation of AKT was repressed (p < 0.05). In conclusion, short-term oral UMP or UR administration could regulate fatty acid composition and lipid metabolism, thus providing energy for early-weaned piglets.

Uridine Metabolism and Its Role in Glucose, Lipid, and Amino Acid Homeostasis

“…Uridine catabolism can also lead to an increase in cellular acetyl-CoA pool, which in turn increases protein acetylation [10]. Our previous studies showed that oral administration of uridine stimulated intestinal development, promoted nucleotide transport, improved growth performance, and regulated the fatty acid composition and lipid metabolism in weaned piglets [41][42][43][44]. We have demonstrated that maternal dietary supplement UR contributed to reducing the occurrence of diarrhea by regulating cytokine secretion and intestinal mucosal barrier function of suckling pigs [45].…”

Maternal supplementation with uridine influences fatty acid and amino acid constituents of offspring in a sow–piglet model

“…In addition, as a nuclear receptor, PPAR regulates placental development and lipid metabolism (51,52) . Our previous study in early-weaned piglets showed that short-term UR treatment might regulate protein expression of mTOR and AKT pathways (16) . Similarly, we found that UR treatment could improve the phosphorylation of mTOR and AKT, raptor, which indicated that UR may regulate placental transfer through mTORC1 and AKT pathway.…”

“…UR also plays an important role in regulating energy homoeostasis and bile acid metabolism via regulating lipid metabolism (11) . Short-term UR treatment to early-weaned piglets might stimulate de novo lipid synthesis via the AKT pathways (16) , it also affected cholesterol and bile acid metabolism of mice (17) and the diurnal variations of lipid metabolism in the liver of mice can be regulated by UR (18) . Thus, UR plays an important role in the metabolism of amino acids and fatty acids in the sows.…”

Maternal yeast‐based nucleotide supplementation decreased stillbirth by regulating nutrient metabolism

“…Uridine (UR) comprises one of the nucleotides, and dietary supplementation with UR modulates lipid and AA metabolism in mice or sows 8–10 . Most interestingly, short‐term oral UR 5'‐monophosphate (5'‐UMP) or UR to piglets could improve energy utilization by modifying lipid metabolism 11 . Thus, nucleotides play an important role in regulating the body's amino acid and lipid metabolism.…”